Anopheles funestus could severely limit available resistance management options. Unfortunately, the molecular basis of such cross‐resistance remains uncharacterized in An. funestus, preventing effective resistance management. Here, using a genomewide transcription profiling, we revealed that metabolic resistance through upregulation of cytochrome P450 genes is driving carbamate resistance. The P450s CYP6P9a,CYP6P9b and CYP6Z1 were the most upregulated detoxification genes in the multiple resistant mosquitoes. However, in silico docking simulations predicted CYP6Z1 to metabolize both pyrethroids and carbamates, whereas CYP6P9a and CYP6P9b were predicted to metabolize only the pyrethroids. Using recombinant enzyme metabolism and inhibition assays, we demonstrated that CYP6Z1 metabolizes bendiocarb and pyrethroids, whereas CYP6P9a and CYP6P9b metabolize only the pyrethroids. Other upregulated gene families in resistant mosquitoes included several cuticular protein genes suggesting a possible reduced penetration resistance mechanism. Investigation of the target‐site resistance in acetylcholinesterase 1 (ace‐1) gene detected and established the association between the new N485I mutation and bendiocarb resistance . The detection of multiple haplotypes in single mosquitoes after cloning suggested the duplication of ace‐1. A TaqMan genotyping of the N485I in nine countries revealed that the mutation is located only in southern Africa with frequency of 10–15% suggesting its recent occurrence. These findings will help in monitoring the spread and evolution of carbamate resistance and improve the design of effective resistance management strategies to control this malaria vector.Carbamates are increasingly used for vector control notably in areas with pyrethroid resistance. However, a cross‐resistance between these insecticides in major malaria vectors such as  Anopheles mosquitoes across Africa. In the major vector Anopheles funestus, both pyrethroid and carbamate resistances are increasingly reported in southern and West Africa with the fear that such resistance could disrupt malaria control , southern Malawi. This locality has been already described in previous studies  , unexposed F1 mosquitoes from Chikwawa to insecticide  and also from unexposed mosquitoes of the fully susceptible laboratory strain FANG  using the Picopure RNA Isolation Kit . To assess the possible cross‐resistance mechanism, RNA was also extracted from three batches of mosquitoes from Chikwawa alive after exposure to 0.75% permethrin . Microarray protocol was performed as previously described .RNA was extracted from three batches of ten 2‐ to 5‐day‐old Rb), permethrin‐resistant (Rp), control (C) (mosquitoes from Chikwawa not exposed to insecticide) and FANG (S) samples was used as the template for cDNA synthesis using Superscript III (Invitrogen) with oligo‐dT20 and RNase H according to the manufacturer's instructions. qRT–PCR amplification was performed as described previously  and actin 5C (AGAP000651).The expression patterns of some of the genes most associated with carbamate or cross‐resistance with pyrethroids from microarray were validated by qRT–PCR using the primers listed in Tables S1–S5 (Supporting information). One microgram of total RNA from three biological replicates for the bendiocarb‐resistant (The full length of the candidate resistance genes was amplified from cDNA using the Phusion High‐Fidelity DNA Polymerase (Thermo Scientific) and cloned into the pJET1.2/blunt cloning vector (Thermo Scientific). The primers used are listed in Table S5 (Supporting information). After sequence analysis, one clone that was predominant in the resistant mosquitoes was selected for further analysis.CYP6Z1 gene was fused to a bacterial ompA+2 leader sequence and expressed in E. coli JM109 cells using the pCW‐ori+ vector as previously described .The CYP6Z1 was co‐expressed with ompA+2 modification together with An. gambiae CYP450 reductase in E. coli JM109 at 21 °C and 150 rpm as described previously  in parallel with –NADPH (negative control). KM and Vmax were established from the plot of substrate concentrations against the initial velocities and fitting of the data to the Michaelis–Menten equation or sigmoidal module in the case of bendiocarb, using the nonlinear regression as implemented in the graphpad prism 6.03 . Catalytic constants and efficiencies were automatically predicted from the steady‐state parameters by the Prism software.Kinetic analysis with pyrethroids and bendiocarb was carried out with conditions established as linear with time and amount of enzyme. Steady‐state parameters were obtained by measuring the rate of reaction under linear conditions for 10 min while varying the substrate concentration from 0 to 20 μm probes were screened with 10 pmol P450 membranes in a total volume of 250 μL containing 1 mm glucose‐6‐phosphate (G6P), 0.1 mm NADP+ and 1 U/mL glucose‐6‐phosphate dehydrogenase (G6PDH), buffered with 50 mm potassium phosphate buffer (pH 7.4) containing 5 mm MgCl2. Protocol was as described previously , coumarins  and diethoxyflourescein (DEF). Initially, 1‐μet al. 50 values calculated from the residual activities towards DEF in the presence of insecticides.For each enzyme, inhibition assays were conducted with DEF, test inhibitors  and miconazole (a positive P450 inhibitor) to assess the degree of binding to pyrethroids and carbamates in the presence of high affinity probe, DEF. The assay was carried out as described in previous studies , deltamethrin (ZINC01997854) and bendiocarb (ZINC02015426), were retrieved from the library of ZINC12 (https://zinc.docking.org/) database in mol2 format  (Yano rin ZINC0854 and brin ZINC0854 and b7 DeLano .ace‐1) spanning the G119S and F455W mutations previously associated with carbamate resistance  and from Chokwe (Mozambique) were screened using a pyrosequencing assay designed to sequence the region encoding this mutation. PCR amplification and pyrosequencing reactions were carried out as previously described  was amplified using cDNA from bendiocarb‐resistant mosquito samples from Malawi, Mozambique, Benin and from the susceptible FANG strain. Further details of the sequencing procedures are provided in Appendix S1 (Supporting information).The full length of the acetylcholinesterase 1 . The TaqMan reactions were performed in a 10 μL final volume containing 1 × SensiMix (Bioline), 800 nm of each primer and 200 nm of each probe, using the Agilent MX3005P machine. The following cycling conditions were used: 10 min at 95 °C, 40 cycles of 15 s at 92 °C and 1 min at 60 °C. These assays were used to assess the correlation between the genotypes of each mutation and bendiocarb‐resistant phenotypes. Twenty‐five mosquitoes that were dead after 1 h of 0.1% bendiocarb exposure (susceptible) and 25 alive mosquitoes (resistant) from Chikwawa  and Chokwe  were genotyped. In addition, for the Malawi samples, another comparison was made between the two phenotypes after a 45‐min exposure to bendiocarb.To genotype two of the mutations detected in An. funestus s.s. from nine countries belonging to different regions of Africa were genotyped by TaqMan: Benin , Ghana , Burkina Faso , West Africa; Cameroon , West‐Central Africa; Uganda  and Kenya  in East Africa; and Malawi , Zambia  and Mozambique  in southern Africa.To assess the geographical distribution of the N485I mutation across Africa, 30 field‐collected female ace‐1 gene spanning the N485I mutation from exon 5 to exon 7 was amplified and sequenced in ten carbamate‐resistant and ten susceptible mosquitoes from Chikwawa in Malawi. The primers are listed in Table S5 (Supporting information). The PCR conditions and polymorphisms analyses were the same as described above for the fragment spanning G119S.To assess the presence of a selective sweep associated with the N485I mutation, a fragment of the ace‐1 gene in An. funestus, the fragment of the gene spanning exons 5–7 was cloned and sequenced for 5 mosquitoes with different genotypes after TaqMan assay.To assess the possible duplication of the ace‐1 compared with the 485I mutant and the spacial positioning of the mutations, homology models were generated with modeller 9v2    (100% resistant) and the control wild type with only 40% resistance . In addition, consideration was also given to probes that were commonly upregulated in the R‐S and C‐S (Tables Priority was given to the list of probes significantly upregulated in the bendiocarb‐resistant vs. control mosquitoes (Rb‐S) or between the control and FANG (C‐S). The cytochrome P450 gene CYP6P9a appears to be the best candidate detoxification gene associated with bendiocarb resistance in the Anopheles funestus from Chikwawa, as two out of three probes of this gene were consistently overexpressed in the three Rb‐C, Rb‐S and C‐S comparisons  and R‐S (FC10.8 and 10.8). This list of cytochrome P450 genes commonly overexpressed in both R‐C and R‐S also includes two probes of the CYP6P9b genes, as well as one probe each of CYP6P4b and CYP6P5 .The list of genes commonly overexpressed in Rb‐C also detected several cytochrome P450 probes, among which two probes belonging to the CYP4G16 are the most upregulated (FC9.1 and 8.7)  belongs to several cytochrome oxidase subunit III  and also an EST encoding a monkey king protein gene  (FC‐20.5 in Rb‐S and ‐46.8 in C‐S) . There was also an isoform c gene (AGAP012280) (FC‐31.7 in Rb‐S and 65.2 in C‐S).The most downregulated probe in all comparisons ‐ and bendiocarb (2.9‐fold)‐resistant samples than in the control nonexposed samples. This is similar to microarray results suggesting a possible induction of this gene or a higher expression in resistant mosquitoes. Similar trend was observed for the argininosuccinate lyase which was 6‐ and fourfold more overexpressed in permethrin‐ and bendiocarb‐resistant samples, respectively, than the control. The CYP9J11 was the only gene significantly more overexpressed in resistant bendiocarb than resistant permethrin (sixfold more) and control (ninefold). Overall, there was a significant correlation between qRT–PCR results and microarray   than the previously expressed CYP6P9b, CYP6P9a and CYP6M7  and deltamethrin   for both pyrethroids , resulting in catalytic efficiencies (Kcat/KM) of 0.43/min/μm and 0.58/min/μm, respectively, for permethrin and deltamethrin. This is comparable to values established for other characterized An. funestus P450s   with possible polar metabolites eluting in the beginning of the HPLC chromatogram   and propoxur, except for CYP6M7 for which a low but significant depletion was observed . Kinetic analysis of CYP6Z1 metabolism of bendiocarb established that this P450 exhibits allosteric kinetics with positive cooperativity (h = 1.06) for bendiocarb. Dose–response curve was modelled using the relevant module in the GraphPad Prism, as described (Copeland KM of 0.17 μm) and low turnover of 0.43/min, suggesting more than one binding site for bendiocarb within its active site. The catalytic efficiency for bendiocarb  was calculated as 2.53/min/μm.Metabolism assays with carbamates revealed that CYP6Z1 also metabolizes bendiocarb  Fig. A. In conCopeland . The enzKM fourfold less than that of CYP6P9a . CYP6Z1 has high turnover for diethoxyfluorescein with catalytic efficiency more than 500‐fold than obtained with CYP6P9a and more than sixfold than the efficiency of CYP6P9b .The potential O‐dealkylation properties of the recombinant CYP6Z1, CYP6P9a and CYP6P9b was investigated with six fluorescent substrates, in order to identify the most suitable probe to conduct inhibition assays. All the three recombinant P450s exhibited preferential activity towards diethoxyfluorescein (DEF), but CYP6P9b and CYP6Z1 portrayed good activity as well with methoxyresorufin Fig. A. Kineti50 values . CYP6Z1 shows lower affinity for both permethrin and deltamethrin compared with the other P450s with IC50 slightly lower with deltamethrin than permethrin. All three P450s show comparable affinity towards pseudo‐pyrethroid etofenprox and strong affinity towards the organophosphate chlorpyrifos  were obtained with carbamates bendiocarb and propoxur indicating that these insecticides are not good binders of these P450s. In contrast, for CYP6Z1, IC50 values of 9.5 μm and 8.9 μm, respectively, were obtained for bendiocarb and DDT indicative of good binding.For CYP6P9a and CYP6P9b, very high ICet al. et al. In order to further understand the reasons why CYP6P9a and CYP6P9b could only metabolize pyrethroids while CYP6Z1 metabolizes both pyrethroids and bendiocarb, a 3D homology models of these P450s were created. The CYP6Z1 metabolizes pyrethroids because it accommodates both permethrin and deltamethrin which docked into its active site productively with the 4ʹ spot of benzyl ring above the haem at a distance of 4.7Å and 5.0Å, respectively . In this posture, ring hydroxylation, characteristic of pyrethroid metabolizers is possible  were observed when the carbamate docked into the active sites of CYP6P9a and CYP6P9b. This is in contrast with the higher values obtained from docking of bendiocarb with CYP6Z1. The insecticide docked in the active site of CYP6P9b closer than in CYP6P9a, but with the 2ʹ dimethyl group oriented towards the haem at a distance of 7.6Å Fig. A, far awAn. gambiae and Culex quinquefasciatus , intron 3 (from 209 to 287), exon 4 (from 288 to 485) and partial intron 4 (from 486 to 559) was obtained from bendiocarb‐resistant and susceptible mosquitoes from Chikwawa, Malawi. A summary of the polymorphism pattern is presented in Table S4 and Fig. S3A (Supporting information). The G119S mutation which confers carbamate and organophosphate resistance in An. funestus population from Chikwawa.To confirm the absence of the G119S mutation, a pyrosequencing reaction was performed in 100 field‐collected mosquitoes from Chikwawa. All the pyrogram traces showed only the GGA codon which codes for glycine  confirming that the G119S mutation is not present in the ace‐1  detected a total of 45 substitution sites of which 4 were nonsynonymous inducing an amino acid changes, observed only in Malawi and Mozambique, but not in Benin . The constructed maximum‐likelihood tree of these haplotypes revealed that they cluster according to their country of origin . The common residues of the catalytic triad S200 (S358 in An. funestus sequence), E327 (E484) and H440 (H598) and the six cysteine residues which form the three intra‐subunit disulphide bonds are all conserved in An. funestus .A direct sequencing of the full‐length cDNA and clones of An. funestus particularly. Three of the four amino acid changes observed are located in the signal peptide region of the ace precursor which gets cleaved from the mature protein and consequently are unlikely to impact the activity of this enzyme. With reference to the An. funestus sequence, these are the A27T (G to A at position 102 bp) and the A36S (G to T at position 127 bp) both detected in Malawi clones, and the A50T (A to G at position 148 bp) detected in all Mozambican clones. The only mutation in the mature protein is the N485I (AAC to ATC at 1928 bp) located 44 amino acid away from the H440 residue of the catalytic triad. Further analysis on this ace‐1 sequence is provided in Appendix S1 (Supporting information).The G119S was confirmed to be absent in Because of its location near the catalytic triad residue H440, the N485I mutation was further genotyped between bendiocarb‐resistant and susceptible individuals, to establish a possible correlation with resistance using two time points. The TaqMan assay unambiguously detected respective genotypes  in 25 susceptible and 25 resistant mosquitoes at the two time points.P = 0.012)  was observed when comparing the frequency of the RS and SS genotypes between phenotypes . Furthermore, the correlation was also significant when comparing the frequency of the susceptible and the resistant alleles in both phenotypes with OR = 5.5 (P = 0.0004). No homozygote‐resistant genotype (RR) was detected even in resistant mosquitoes . In contrast, no such correlation was found for the A50T mutation (data not shown). The correlation of the N485I mutation with bendiocarb resistance indicates that this TaqMan assay is a suitable diagnostic tool to detect and map the distribution of bendiocarb resistance in An. funestus in Africa.At 60‐min exposure time to bendiocarb, a significant correlation was observed between the N485I genotypes (RS and SS) and bendiocarb resistance with an odds ratio (OR) of 2.47  and intron 5 exhibited several sites with multiple polymorphisms. Overall, the ace‐1 remains polymorphic with no evidence of selection even in resistant mosquitoes . However, a phylogenetic tree indicates that all resistant haplotypes harbouring the 485I‐resistant allele cluster tightly  suggesting a common origin for this mutation or background selection on such mosquitoes.To assess the presence of an An. funestus ace‐1 N485I mutation mapped to the external loop joining the α28,9 with β9 .While most of the mutations which impact on insects acetylcholinesterase activity were reported to map to the location within or adjacent to the active site gorge Fournier , in contAnopheles funestus and revealing the extent of cross‐resistance with pyrethroids, this study has addressed this important knowledge gap.Tackling the growing problem of insecticide resistance is paramount to sustain the progress so far made in reducing the burden of malaria. Understanding the molecular basis of resistance to each insecticide class and possible cross‐resistance pattern is a prerequisite for the implementation of resistance suitable management strategies to control this malaria vector. By deciphering the genetic basis of carbamate resistance in the major vector CYP6Z1 plays in this cross‐resistance. First, it was consistently among the most overexpressed detoxification genes in resistant mosquitoes. Second, all functional analyses supported the ability of CYP6Z1 to bind and metabolize bendiocarb. CYP6Z1 exhibited a high affinity to both insecticide classes in contrast to other P450s tested and was able to metabolize bendiocarb with potential polar metabolites which eluted in the beginning of a chromatogram. Indeed, studies have shown that carbamate metabolism proceeds via hydrolysis, oxidative attack and conjugation  and DDT and dicyclanil for CYP12D1  in pyrethroid‐resistant mosquitoes. Therefore, the use of pyrethroids will not automatically select for resistance to carbamates in An. funestus, at least not at the same speed as the contributing genes vary also in their relative importance in each resistance. However, there should nevertheless be a note of caution as one cannot rule out the possibility for CYP6P9a to be involved in the second stage of biotransformation of the primary bendiocarb product into more water‐soluble metabolites to be conjugated and excreted. Further studies will be needed to assess this hypothesis.However, amidst the danger posed by Rb‐C comparison. This suggests that besides the upregulation of cytochrome P450 genes, a reduced penetration of insecticides through a thickening of the mosquito cuticle is likely associated with the bendiocarb resistance in An. funestus. Furthermore, the overexpression of the CYP4G16 gene, an ortholog of the CYP4G1 gene in D. melanogaster which is involved in cuticular hydrocarbon biosynthesis . The microarray data were submitted to Array Express, Accession nos.: E‐MTAB‐3745 (4 × 44k) and E‐MTAB‐3747 (8 × 60k).Fig. S1 Venn diagrams summarising the number of probes differentially regulated in each of the microarray hybridisation (P < 0.01 with 2‐fold change).Fig. S2 Functional characterisation of candidate resistance genes. Fig. S3 Polymorphism patterns of ace‐1 in field populations of Anopheles funestus.Fig. S4 Alignment of full‐length ace‐1 sequences.Fig. S5 Genotyping of N485I mutation and genetic diversity of the fragment spanning the N485I mutation between bendiocarb susceptible and resistant mosquitoes in Malawi.Click here for additional data file.Table S1 Additional probes from detoxification genes and genes associated with bendiocarb resistance.Table S2 Probes from detoxification genes or resistance associated genes commonly up‐regulated in both R‐S.Table S3 Kinetic constants for probe substrates and in silico binding parameters of insecticides.Table S4 Genetic parameters for the ace‐1 gene in natural populations of Anopheles funestus.Table S5 List of primers used in this study.Click here for additional data file.Appendix S1 Supplementary methods and results. Click here for additional data file. Click here for additional data file.


Clinoptilolite zeolite and compost could be used to control N loss from urea by controlling NH4+ and NO3− release from urea. Soil incubation and leaching experiments were conducted to determine the effects of clinoptilolite zeolite and compost on controlling NH4+ and NO3− losses from urea. Bekenu Series soil  was incubated for 30, 60, and 90 days. A soil leaching experiment was conducted for 30 days. Urea amended with clinoptilolite zeolite and compost significantly reduced NH4+ and NO3− release from urea (soil incubation study) compared with urea alone, thus reducing leaching of these ions. Ammonium and NO3− leaching losses during the 30 days of the leaching experiment were highest in urea alone compared with urea with clinoptilolite zeolite and compost treatments. At 30 days of the leaching experiment, NH4+ retention in soil with urea amended with clinoptilolite zeolite and compost was better than that with urea alone. These observations were because of the high pH, CEC, and other chemical properties of clinoptilolite zeolite and compost. Urea can be amended with clinoptilolite zeolite and compost to improve NH4+ and NO3− release from urea.Improper use of urea may cause environmental pollution through NH Leaching of NO3− from urea leads to increase in NO3− concentrations in surface and ground water [3− in the soil solution moves along with the water. Because NH4+ is positively charged, it is held by the negative sites of soils ; therefore, NH4+ leaches less in mineral soils which are particularly high in clay [4+ leaching is significant in coarse-textured sands and some muck soils [Depending on soil pH, moisture, and application methods, urea undergoes chemical transformation to produce either NHor NO3− . Nitrogend water . Leachinck soils .3− is not absorbed by the plant root system, it is leached below the root zone of plants, thus contaminating groundwater [4+ and NO3− in soils. However, this is a challenge because it requires simultaneous management of N fertilizers and water. Loss of mineral N from agricultural systems is difficult to achieve through reduction of N fertilizers use [Nitrogen leaching loss in soils is a risk because if NOundwater . Accordiundwater , optimizzers use . One of 4+ ions against microbial nitrification [Clinoptilolite zeolite can be used to control N loss from urea because of the small molecular size of the open-ringed structure of clinoptilolite zeolite which physically protects NHfication . Clinoptfication . Adoptiofication . Studiesfication –15. The fication –18.−1 (25% dry substance) and 90 g day−1 (40% dry substance) by a broiler [As the third largest producer of chicken products in Asia, chicken manure disposal is becoming a challenge in Malaysia. In 2012, 674 million and 637 million day-old chicks and broilers, respectively, were produced . Wastes  broiler . Cocompo4+ and NO3− release from urea using clinoptilolite zeolite and composts. Thus, the objective of this study was to determine the effects of clinoptilolite zeolite and compost (produced by cocomposting rice straw and chicken manure) on controlling NH4+ and NO3− loss from urea.Cocomposting is a simple method which converts, for example, chicken manure and rice straw into valuable organic amendments. The process of cocomposting is essential for aforementioned wastes to be safely, conveniently, and efficiently used as soil organic amendment . This isTypic Paleudults). The soil was sampled at 0–20 cm depth from an uncultivated area at Universiti Putra Malaysia, Bintulu Campus Sarawak, Malaysia. The soil was air-dried and ground to pass a 2.0 mm sieve for initial characterization, incubation, and leaching experiments. Field capacity and bulk density of the soil were determined by the method described by Tan [The soil used in this study was Bekenu Series (d by Tan . Soil fid by Tan . Soil bud by Tan . The cord by Tan .Soil texture was determined using the hydrometer method . The hydμm) was placed on the loading head of the machine. Samples were combusted at 1075°C and the reading of total C and N was obtained directly from computer software. The loss of weight represented the weight of C and organic matter content was estimated by multiplying organic matter value; 58% of organic matter is C [The pH of the soil was determined in a ratio of 1 : 2 (soil : distilled water suspension) using a digital pH meter . A 10 g ter is C . Soil avter is C  followedter is C . A 5 g oAcid molybdate stock solution (Reagent A) and ascorbic acid stock solution (Reagent B) were prepared for colour development procedure. A standard P solution (standard solution 1) and standard solution 2 were prepared and used to prepare working solutions ranging from 0 to 0.6 ppm. 0, 1, 2, 3, 4, 5, and 6 mL of standard solution 2 were pipetted into 50 mL volumetric flask using micropipette and added with 8 mL of Reagent B to develop the blue colour. A 4 mL of the supernatant was pipetted into 50 mL volumetric flask. Reagent B of 8 mL was added to develop the blue colour. This solution was diluted to mark with distilled water and maximum blue colour was allowed to develop . The abs4OAc solution for 5 hours. Their concentrations in the extract were determined using Atomic Absorption Spectrophotometry . Soil CEC was determined by leaching the soil samples with 100 mL of 1 M NH4OAc for 5 hours [4+ and available NO3− after which their concentrations were determined using steam distillation. A sample of 5 g soil was extracted with 50 mL of 2 M KCl solution and shaken for 1 hour. Afterwards, it was filtered using Whatman filter paper number 2. Exchangeable NH4+ was determined by pipetting 20 mL of extractant into distillation tube, added with 0.2 g of MgO, and distilled for 5 min. A 10 mL of boric acid with bromocresol green and methyl red indicator was used to trap NH4+. Afterwards, the distillation was continued by adding 0.2 g Devarda's alloy to the sample and the process of distillation proceeded for another 5 minutes. The distillates of NH4+ and NO3− were titrated with 0.01 M HCl. The texture of the soil was sandy loam with a bulk density of 1.51 g m−3. The texture of the soil and bulk density are consistent with those reported in Soil Survey Staff [Exchangeable cations were extracted using the leaching method . A 10 g  5 hours . Afterwa 5 hours . Then, t 5 hours . The met 5 hours  was usedey Staff . The seley Staff . The excey Staff .2SO4) and digested. A tablet of selenium catalyst was added, shaken, and left to equilibrate for 30 minutes. The samples were then digested at 180°C for 1 h and then at 320°C for 4 to 5 h until samples were colourless. 10 mL of the digested sample was pipetted into 50 mL distillation flask and added with 10 mL 40% NaOH. 10 mL of boric acid plus indicator solution was placed at the end of the condenser in the distillation apparatus to trap NH3 released. The mixture was distilled until the boric acid-indicator solution doubled the original volume. The distillate solution was titrated with 0.01 M HCl to estimate N content in the clinoptilolite zeolite. The pH, exchangeable NH4+, and available NO3− of the clinoptilolite zeolite were determined using the method described previously [4OAc was used. The CsCl method was used to avoid underestimation of CEC of the clinoptilolite zeolite as the method does not lead to entrapment of ammonium ions in the channels of the clinoptilolite zeolite. The exchangeable K, Ca, and Mg of the clinoptilolite zeolite were extracted using the method of Ming and Dixon [The clinoptilolite zeolite used in this study was in powder form. Total N of the clinoptilolite zeolite was determined using Kjeldahl method . 0.5 g oeviously , 32. Theeviously . The prond Dixon  and thei4+, NO3− P, Ca, Mg, and K concentrations increased after the cocomposting process (Zea mays L.) tested on compost and distilled water (control) using the method described by Zucconi et al. [Spinacia oleracea) growth on peat-based growing medium (control) [The selected chemical characteristics of the compost were determined using standard procedures as outlined previously –32. The  process . The lowi et al.  and spincontrol)  and comp4/E6 ratio of the humic acid, the absorbance at 465 nm and 665 nm was measured using UV-Vis spectrophotometer  on solution of 3 mg of each humic acid in 10 mL of 0.05 M NaHCO3. The ratio of absorbance at 465 nm and 665 nm gave the E4/E6 ratio [The humic acid fractions after the composting process were extracted with 0.5 M NaOH, precipitated at pH 1.0 with 6 M HCl, and then purified with 100 mL distilled water . The car250 g soil (no urea) (T0),250 g soil + 7.40 g urea without additives (T1),250 g soil + 7.40 g urea + 6 g clinoptilolite zeolite (T2),250 g soil + 7.40 g urea + 6 g compost (T3),250 g soil + 7.40 g urea + 6 g clinoptilolite zeolite + 6 g compost (T4).A soil incubation experiment was carried out for 90 days in the Soil Science Laboratory of Universiti Putra Malaysia, Bintulu Sarawak Campus, Malaysia. The treatments evaluated in this experiment were Zea mays L. cultivation [4+ and NO3− contents were determined using the method of Keeney and Nelson [The rates of urea , clinopttivation . The soitivation , total Ntivation , whereasd Nelson .4+ and NO3− using the method of Keeney and Nelson [4+, and available NO3− using the standard procedures as outlined previously [The soil leaching experiment comprised the same treatments as in the incubation experiment. All treatments were thoroughly mixed and scaled down to the amount of 64 g soil. The mixture was then filled in leaching tubes and leached with distilled water after which the leachates were collected at three-day interval based on five-year rainfall data obtained from the Sarawak Meteorological Department, Malaysia . Afterwad Nelson  whereas eviously , 32.P ≤ 0.05. The Statistical Analysis System version 9.2 was used for the statistical tests.The soil incubation experiment was a split-block experimental design in triplicate with two factors, namely, time of incubation  and treatments . The experimental design of the soil leaching experiment was completely randomized design (CRD) with three replications. Analysis of variance (ANOVA) was used to detect treatment effects whereas Tukey's test was used to compare treatment means at 4+, and available NO3− but did not affect soil pH at 30 DAI, 60 DAI, and 90 DAI  and urea with additives  on total N at 30 DAI were not significantly different . However and urea4+ and NO3− into the clinoptilolite zeolite lattice [c kg−1) of the clinoptilolite zeolite used in this study. According to Ferguson and Pepper [4+ through cation exchange. Besides retaining large quantities of NH4+, these minerals also interfere with the process of nitrification [The retention of soil total N in T4 could also be due to absorption of NH lattice , 16. Thid Pepper , zeolitefication , 16.4+, OH−, and CO32− ions are released to increase soil pH [4+ for instance is very slow when pH is in the range of 5 to 6 [Urea with clinoptilolite zeolite (T2) significantly increased soil pH compared with those of soil alone (T0) and urea without additives (T1) at 30 DAI and 90 DAI but not at 60 DAI . The soi soil pH . The pH f 5 to 6 . Accordif 5 to 6 , nitrifi4+ was significantly higher in the urea with clinoptilolite zeolite and compost treatments  than in urea without additives (T1) and soil alone (T0) at 30 DAI, 60 DAI, and 90 DAI, respectively  and humic substances of compost (T3 and T4). The retention of soil exchangeable NH4+ could be attributed to the high CEC of the clinoptilolite zeolite. According to Kithome et al. [4+ retained by clinoptilolite zeolite is generally released slowly because of the CEC of this zeolite and nitrification in the soil. Retardation of nitrification in this study may have occurred due to clinoptilolite zeolite, as the small molecular size of the open-ringed structure of clinoptilolite zeolite (10−6–10−9 m) physically protects NH4+ against microbial nitrification [4+ in urea with compost treatments (T3 and T4) was possible because of the humic acid content (15.20%) of the compost used in this study. The carboxyl, phenol, and total acidity of the humic acid of the compost used in this study were 450 cmolc kg−1, 300 cmolc kg−1, and 750 cmolc kg−1, respectively  as demonstrated in 3− from the soil because of its C/N ratio (15.17)  as presented in 3− and phosphates [3− at 30 DAI, 60 DAI, and 90 DAI in T4 3− as it influences nitrification and denitrification. Loss of NO3− to N2O and NO emissions increase under low soil pH [All the mixtures  significantly increased soil available NO (15.17) . As repoa et al.  reportedosphates . The sig soil pH .4+ and NO3− from soil in the leaching experiment for 30 days are presented in Figures 4+ and NO3− from soil compared with soil alone (T0) and urea alone (T1). Treatments 2 and 4 (mixtures of urea and clinoptilolite zeolite) reduced NH4+ leaching because the clinoptilolite zeolite has high affinity for NH4+  whereas NO3− was absorbed into the channels of the clinoptilolite zeolite. Huang and Petrovic [4+ and NO3− concentrations in leachate and increased moisture retention in the soil due to increased soil surface area and CEC. Thus, applying clinoptilolite zeolite to soils may reduce leaching of NH4+ and NO3−. The significant reduction in leaching of NH4+ and NO3− in T2 and T4 reported in this study  are clearly demonstrated in Figures 4+ and NO3− from T1, T2, T3, and T4 only).For T3 and T4, leaching of NH Figures  because mic acid . The str4+ and NO3− leaching loss compared with T1 is presented in 4+ and NO3− leaching losses compared with urea without additives (T1). Treatments 3 and 4 significantly minimized NH4+ and NO3− leaching losses partly because the compost served as a source of organic matter for N stabilization in the soil. This is because N is stored in soils in organic form; thus the quantity and nature of organic matter and its decomposition in the soil have effect on the long-term availability of N. The clinoptilolite zeolite in T2 and T4 was able to retain NH4+ because of the specific selectivity of the clinoptilolite zeolite for NH4+ [Another evidence to support the effectiveness of T2, T3, and T4 in controlling NHor NH4+ . This isor NH4+ .4+ and available NO3− compared to urea without additives (T1) (4+ and available NO3− were lower in urea without additives (T1) at the end of leaching study because they were leached as discussed previously , urea with clinoptilolite zeolite and compost  showed significant concentrations of soil exchangeable NHves (T1) . Soil exeviously . The avafication . In a reto NO3− .4+ and available NO3− compared with urea without additives (T1) partly due to the ability of the compost to increase water holding capacity of soils. Due to this, leaching of NH4+ and NO3− is reduced. This is possible because leaching losses of N occur when soils have more incoming water than the soil can hold. It was also reported that the slow release nature of compost-N renders leaching of NO3−-N [The compost in T3 and T4 improved retention of soil exchangeable NH NO3−-N . As repo NO3−-N , 54, app4+ and NO3− as discussed previously in Figures The soil total N after the leaching experiment without subtracting the contribution of T0 from T1, T2, T3, and T4 is shown in 3 could be the reason for lower leachate pH in T1. This is because H+ released from NH4+ lowered pH of the leachate. The ability of T2 and T4 to maintain the pH of the leachates was because of the buffering capacity of clinoptilolite zeolite and compost. In a related study, Prasad and Foster [The pH of leachate over 30 days of leaching is summarized in d Foster  stated td Foster .Urea amended with clinoptilolite zeolite or compost, or combination of clinoptilolite zeolite and compost, reduced nitrogen (leaching of ammonium and nitrate) loss by retaining ammonium and nitrate in soil. The findings in this present study suggest that urea can be properly managed if it is amended with clinoptilolite zeolite or compost or combination of clinoptilolite zeolite and compost. Field application of our findings is being evaluated in our ongoing field experiment.


A quantum mechanical (QM) method rooted on density functional theory (DFT) has been employed to determine conformations of the methane-thiosulfonate spin label (MTSL) attached to a fragment extracted from the activation loop of Aurora-A kinase. The features of the calculated energy surface revealed low energy barriers between isoenergetic minima, and the system could be described in a population of 76 rotamers that can be also considered for other systems since it was found that the The online version of this article (doi:10.1007/s00214-016-1859-z) contains supplementary material, which is available to authorized users. The most widely employed spin label for studies of the structure and dynamics of biomolecules , 2, throThe MTSL is endowed of high flexibility and the knowledge of the potential surface is required in order to model its internal dynamics –7. In thα-helix systems of the T4 Lysozyme protein [In the previous literature, similar approaches were adopted by Tombolato et al.  using th protein –7 and re protein , 9. ConsWe performed a conformational analysis of the potential energy surfaces of the MTSL side chain attached to a fragment extracted from activation loop of Aurora-A kinase protein with the purpose to characterize its geometrical parameters and describe the system in a limited number of rotamers. We carried out this work to establish a basis for more advanced modelling approaches involving molecular dynamics (MD) simulations that require different initial starting conformations of the MTSL for appropriate statistical analyses.A short unit peptide was extracted from the X-ray crystal structure of the Aurora-A kinase domain  basis set using the α atom of the CH3–CO–NH–Cα–CO–NH–CH3 fragment extracted from the minimized and equilibrated structure of the Aurora-A kinase domain in which the Cartesian coordinates of the peptide atoms were kept fixed in the configuration obtained after the previous scan. The relaxed scans were performed following the strategy shown in Fig. The MTSL side chain was gradually built in by adding atoms to the Cα–CβH2 group attached to the CH3–CO–NH–CαH–CO–NH–CH3 fragment. The torsional energy profile showed three minima at the values of −160° and ±60° β carbon of the MTSL chain for angles over this range. The shape of the torsional profiles obtained in this work is similar to those seen in α-helices and values of the minima were found to be only slightly different [The S20° Fig. Q1, +80° 20° Fig. Q2 and fo60° Fig. Q3. The coup Fig. Q4. The S80° Fig. Q5. The c−1 for Q2, Q5 and Q7  in the proxyl radical [After calculation of the torsional energy profiles for all five dihedral angles in the unit peptide model, a population of 76 conformations was found at the minima of the torsional energy profiles. The torsional profiles showed low energy barriers from 1 to ~20 kcal/mol and isoenergetic minima in the potential energy surface, indicating that the rotamer population would be fully sampled at room temperature and conformational states are expected to be obtained in the same amount. Also, the Gibbs free energy of the different conformations were seen to be comparable and equal to −6,556,624, −6,556,624 and −6,556,623 kcal mol radical  and in a radical . Hence,  radical .α-helix studied in previous work [The conformational analysis of the MTSL side chain on a short fragment of the Aurora-A kinase activation loop revealed torsional profiles comparable to those observed in fragments of ous work –9. This proteins , 9, it wSupplementary material 1 (DOCX 183 kb)Below is the link to the electronic supplementary material.


Nanoscale liquid transport governs the behaviour of a wide range of nanofluidic systems, yet remains poorly characterized and understood due to the enormous hydraulic resistance associated with the nanoconfinement and the resulting minuscule flow rates in such systems. To overcome this problem, here we present a new measurement technique based on capillary flow and a novel hybrid nanochannel design and use it to measure water transport through single 2-D hydrophilic silica nanochannels with heights down to 7 nm. Our results show that silica nanochannels exhibit increased mass flow resistance compared to the classical hydrodynamics prediction. This difference increases with decreasing channel height and reaches 45% in the case of 7 nm nanochannels. This resistance increase is attributed to the formation of a 7-angstrom-thick stagnant hydration layer on the hydrophilic surfaces. By avoiding use of any pressure and flow sensors or any theoretical estimations the hybrid nanochannel scheme enables facile and precise flow measurement through single nanochannels, nanotubes, or nanoporous media and opens the prospect for accurate characterization of both hydrophilic and hydrophobic nanofluidic systems. Understanding liquid transport through nanoscale confinements is critical in a variety of practical applications, including energy conversion/storage1117891011121314151617918192021222425192021182829303132333435282930313233343537X(t) is recorded and is expected to be governed by the Washburn equation, which for the case of a channel with rectangular cross-section can be written as (The hybrid nanochannel design consists of a test channel (the channel under investigation) seamlessly connected to a reference channel with a different but known mass flow resistance . In a tyP is the capillary pressure, R is the mass flow resistance of the channel per unit length, w and h are channel width and height, and ρ is the fluid density. After the first measurement, liquid is removed from the nanochannel and is introduced from the test channel side for the second measurement (x(t) is then recorded, which is expected to be described by the following equation  and x(t) with A, in the observation channel and the mass flow resistance ratio, η, can be extracted. Consequently, resistance of the test channel can be quantified if the resistance of the reference channel is known. It is worth noting that the test channel can be an individual channel, tube or even nanoporous media, and no matter if it is hydrophobic or hydrophilic, as long as either of test or reference channels allows for spontaneous liquid filling, this technique can be applied.  reaches a plateau at small values of η determined by δx and τ being the spatial resolution and the frame interval , one should possibly choose the test channel as the observation channel such that 1/η would be measured instead of η. This resolves the theoretical limit for accurate characterization of the flow and allows for measurement of very high resistance ratios with a small error. Nevertheless, by designing a long test channel and choosing a high frame rate, the hybrid nanochannel scheme is able to detect very large values of η (>104) with a small error  and bonded to Borosilicate glass by using anodic bonding at 400 °C and 350 Volts. Miscroscope images of a bonded hybrid nanochannel device is shown in h* = 7, 16.2, 38, and 59 nm.In the present investigation, the proposed characterization scheme is utilized to study water transport in hydrophilic silica nanochannels with heights ranging from 7 nm to 59 nm. In our design, nanochannels with the same widths but larger heights (~110–120 nm) serve as the reference channels. This choice of the reference channel height serves several purposes: First, this depth of water in the reference channel can be very easily detected with an optical microscope. Second, this choice of height helps to avoid entrapment of air and creation of bubbles in the reference channel333435ry small . The hybry small . Brieflying DRIE . FinallypH = 7), before each experiment oxygen plasma was applied to the chips for 15 minutes to make the surfaces super hydrophilic and prevent formation of bubbles in the nanochannels. The water Meniscus in nanochannels were tracked by an Olympus inverted microscope model IX81 equipped with a monochromatic HAMAMATSU CMOS FLASH 4.0 C11440 camera recording at up to 900 fps (or at lower rates when not necessary). Position of the meniscus as a function of time was extracted from the recorded frames using a MATLAB image processing code.All the experiments were performed with DI water  at 22 ± 1 °C  It was observed that meniscus moves with a constant speed . In terms of the boundary condition, slip boundary condition has been reported for the hydrophilic channels22Rtheoretical is calculated with ls = 0). In terms of liquid properties, several of previous studies have employed long-range electrostatic forces to explain the slow capillary filling in hydrophilic nanochannels through the Debye-layer correction for the hydraulic resistance. However, this effect known as electroviscosity has been proven insignificant for realistic estimates of central parameters2425321011121315161015et al. also reported a thickness of δ = 9 ± 5 angstroms for the hydration layer in sub-10 nm nanochannels in their capillary filling study324546Representative measured analysis d and 4a.channels . As it’sC of up to 2 in the reference channels .


RT‐PCR assay using the GeXP analyser for the simultaneous detection of four different NA serotypes of H5‐subtype AIVs, effective to control and reduce H5 subtype of avian influenza outbreak.In order to develop a multiplex AIV subtypes H5, N1, N2, N6 and N8 in GenBank. Each gene‐specific primer was fused at the 5′ end to a universal sequence to generate six pairs of chimeric primers, and one pair of universal primers was used for RT‐PCR, and PCR product separation and detection were performed by capillary electrophoresis using the GenomeLab GeXP genetic analysis system.Six pairs of primers were designed using conserved and specific sequences of the cDNA/DNA templates were employed to evaluate the specificity of a multiplex assay with a GeXP analyser. Corresponding specific DNA products were amplified for each gene, revealing amplification peaks for M, H5, N1, N2, N6 and N8 genes from four different NA subtypes of influenza A H5 virus.Single and mixed avian pathogen A total of 180 cloacal swabs were collected from poultry at live bird markets.PCR assay demonstrated excellent specificity, with each pair of specific primers generating only products corresponding to the target genes and without cross‐amplification with other NA‐subtype influenza viruses or other avian pathogens. Using various premixed ssRNAs containing known AIV target genes, the detection limit for the multiplex assay was determined to be 102 copies/μl. The GeXP assay was further evaluated using 180 clinical specimens and compared with RRT‐PCR  and virus isolation.The multiplex XP analyser‐based multiplex assay for four different NA subtypes of H5 HPAI viruses is both highly specific and sensitive and can be used as a rapid and direct diagnostic assay for testing clinical samples.This Ge Influenza virus serotypes are classified based on the combination of two major antigens on the virion, namely haemagglutinin (HA) and neuraminidase (NA). To date, 16 H types and 9 N types have been acknowledged, and a 17th and 18th HA type plus a 10th and 11th NA type have recently been discovered in bats.Laboratory diagnosis is essential when AI is suspected in the field, and currently, RT‐PCR tests are used routinely for AI diagnosis and genotyping. Although conventional and real‐time RT‐PCR protocols have been published for the detection of H5‐subtype HPAIVs in poultry,The AIV reference strains, field isolates and other avian pathogens used in this study are listed in Table http://www.flu.lanl.gov). The designed primers were analysed and filtered using the Premier 5.0 , NCBI Primer Blast  and Oligo 7.0  tool. Each gene‐specific primer was fused at the 5′ end to a universal sequence to generate six pairs of chimeric primers, and one pair of universal primers was used for RT‐PCR . The copy numbers of the ssRNAs for the target genes of AIV  were calculated according to previous methods.Plasmids harbouring genes from AIV  were used to produce ssRNA via 2 (25 μm), 1·25 μl of mixed primers (containing 20–100 nmol/l of 6 pairs of gene‐specific chimeric primers), 1·25 μl of universal primers (100 nmol/l), 1·2 μl of JumpStart Taq DNA polymerase (2·5 U/μl) and 0·5 pg–0·5 ng of cDNA or DNA template. Nuclease‐free water was then added to the PCR to achieve a final volume of 25 μl. PCR was carried out using the GeXP system followed by three steps of amplification according to the temperature switch PCR (TSP) strategy:gexp system software  and matched to the appropriate genes. The peak height for each gene is illustrated in an electropherogram.The reaction system was created using a total volume of 25 μl containing 2·5 μl of 10× PCR buffer, 2·5 μl of MgClThe assay specificities of all the targets were individually tested with pre‐mixed cDNA/DNA in a multiplex PCR assay after optimisation. Other conventional chicken viruses, including all subtypes  and NA (1–9); the HA and NA genes of the reference strains were confirmed by sequencing) of avian influenza virus (AIV), Newcastle disease virus (NDV), infectious bronchitis virus (IBV), avian reovirus (ARV), infectious laryngotracheitis virus (ILTV), seasonal influenza A H1N1, H3N2 and influenza B viruses and nuclease‐free water, were used as negative controls.5 copies to 1 copy per microlitre and then individually subjected to the multiplex assay. The concentrations of specific primers were optimised according to the amplification efficiency of the assay using a single template. The sensitivity of the optimised multiplex GeXP PCR assay was re‐evaluated three times on three different days using 6 pre‐mixed RNA templates ranging from 105 copies to 1 copy per microlitre.The sensitivity of the multiplex assay using the GeXP analyser was evaluated using a previously described method.2 to 106 copies) were selected at random, mixed and tested in the multiplex PCR assay. The results were then compared with those of the single template multiplex PCR assay.Because high quantities of different templates could alter the efficiency of multiplex PCR amplification, different amounts of template , and the swab samples were injected into 9‐ to 11‐day‐old embryonated specific pathogen‐free (SPF) chicken eggs, as previously described.cDNA samples from four different NA subtypes of influenza A H5 virus  were individually used as template to evaluate the specificity of each pair of gene‐specific primers. In mono‐PCR GeXP assays, AIV universal primers were able to amplify the target M gene of all AIV serotypes, although each pair of specific primers generated only the corresponding targeted gene, without cross‐amplification  were tested by the GeXP multiplex PCR assay, and the peak value of the single template was similar to that of the mixed template. For example, two specific amplification peaks were observed when two different templates (AIV‐H5N1 at 102 copies and H5N2 at 106 copies) were tested, and the peak values for AIV‐H5N1 and H5N2 were the same, regardless of whether a single (AIV‐H5N1 or H5N2) or a mixed (AIV‐H5N1 + H5N2) template was utilised (electropherograms not shown). The results of these experiments demonstrate that this interference had a minimal effect on the detection of mixed infection.Two specific amplification peaks were observed when two different templates  standard for AIV subtyping, these methods often have low levels of specificity and sensitivity; in addition, standardisation and reference antisera are difficult to obtain.2 copies/μl. When 180 specimens were analysed, the results for the GeXP PCR assay and the reference method (Virus isolation and sequencing) were in complete agreement for 100% of the specimens, as shown in Table In this study, we successfully established a GeXP method that can simultaneously detect and identify the H5N1, H5N2, H5N6 and H5N8 subtypes of AIV in a single reaction within 4 hours; this GeXP method utilises six different genes primers for M, H5, N1, N2, N6 and N8. Additionally, the specificity of the test was examined using different HA (1–16) and NA (1–9) subtypes of avian influenza virus and nucleic acid of seasonal influenza virus and influenza B virus infecting humans (Table Two distinct advantages of the GeXP assay compared with other nucleic acid‐based tests are the reduced time required and cost‐effectiveness. The cost of the multiplex GeXP assay for simultaneous detection of the four different NA subtypes of H5 AIVs is approximately $6 per test, including primers representing the HA and NA subtypes, when the entire reaction is performed in a single tube. Utilising two 96‐well plates at the same time in the GeXP analyser will further increase the throughput. This method will save much time and cost compared with classical methods of AIV HA and NA subtyping in surveillance programmes.Zhi‐xun Xie designed and coordinated the study. Meng Li designed the primers, optimised the conditions of the GeXP assay and finalised the analysis. All other authors offered much help in the supplement of different clinical samples, shared previous experimental data and approved the final version of the manuscript.We declare that we have no conflicts of interest.


V600E Immunopositive Melanomas Show Low Frequency of Heterogeneity and Association With Epithelioid Tumor Cells: A STROBE-Compliant Article”,1 which appeared in Volume 93, Issue 28 of Medicine, several corrections have been made to Tables 2 and 4.In the article “BRAF2) test was used to see if there is a correlation between BRAF mutation status as determined by pyrosequencing and VE1 expression” should have read “The Cohen's kappa (k) coefficient was used to see if there is a correlation between BRAF mutation status as determined by pyrosequencing and VE1 expression” in the Statistical Analyses section.In addition, the sentence “The Pearson's chi-square (χA k coefficient value has also been added to the Results section.The article has since been corrected online.


But the high-quality film growth is challenging due to its strong surface polarity as well as the difficulty of obtaining the chemical stoichiometry. Here we show that the layer-by-layer growth of homoepitaxial SrTiO3(111) thin films can be achieved in molecular beam epitaxy method by keeping the growing surface reconstructed. And the cation stoichiometry is optimized precisely with the reflective high energy electron diffraction as the feedback signal that changes sensitively to the variation of metal concentration during growth. With atomically well-defined surfaces, the SrTiO3(111) films show high dielectric performance with the charge density modulated in the range of 2 × 1013/cm2 with the back gate voltage lower than 0.2 V. Methods of further broadening the range are also discussed.The six-fold symmetry possessed by the (111) surfaces of perovskite oxides allows the epitaxial growth of novel quantum materials such as topological insulators. The dielectric SrTiO Along this direction, the crystal is stacked with alternative AO3 and B atomic layers. The so-called double perovskite A2BB’O6 in which the B/B’ cations are long-range ordered can be prepared as the [111] superlattice of AO3/B/AO3/B11213141516173/LaCrO3(111) superlattice, the ordered double perovskite La2FeCrO6 film15193 and LaCrO3 where the long-range ordering of Fe/Cr distribution is missing.The low-dimensional transition metal oxides (TMOs) have a rich diversity of remarkable properties129103(111) also provides the opportunity to achieve novel quantum states. It was predicted that the double-layered ABO3(111) might be promising candidate of new topological insulators (TIs)212223s and p orbitals, TMO-based topological materials would be more flexible to control since d electrons with strong correlation contribute significantly to their electronic properties. The honeycomb lattice formed by the two trigonal sublattices on the top two layers of the perovskite (111) surface could reduce the symmetry of crystal field and introduce additional level splitting of d orbitals. Xiao et al. found that LaAuO3(111) has a large topological nontrivial band gap and could realize quantum spin Hall effect at room temperatureThe six-fold symmetry possessed by perovskite ABO3 is a typical perovskite oxide with very high dielectric performance. Its (111) surface matches the lattices of many novel quantum materials with hexagonal in-plane structure. Therefore SrTiO3(111) with an atomically well-defined surface not only serves as an epitaxial growth template, but also can be used as the insulating layer for the modulation of carriers density by gate electric field. Chen et al. reported the control of charge density of Bi2Se3 on SrTiO3(111) in the range of 2 × 1013/cm2 by applying the back gate voltage of 150 V3(111) thin film as a dielectric buffer layer on a metallic substrate would have effectively reduced the gate voltage required for carriers modulation thus making the structure convenient for device applications. However, due to the surface polarity of the ionic crystal3(111) films. In the current work, we achieve the growth of high-quality homoepitaxial SrTiO3(111) films on Nb-doped metallic substrates by molecular beam epitaxy (MBE) method. Reconstructions are formed on the substrate surface and maintained all through the growth to compensate the surface polarity, enabling the layer-by-layer growth with atomically well-defined film surface. And with the monitor of reflective high-energy electron diffraction (RHEED) on the microstructure corresponding to different reconstruction phases of the growing surface, the deposition rates of metal sources are precisely controlled to realize the cation stoichiometry. The films show high dielectric performance. At 6 K, a 50 nm-thick film allows the carriers density modulation in the order of 2 × 1013/cm2 with the gate voltage less than 0.2 V. We present an ideal platform for the design and growth of low-dimensional quantum structures with easy and reliable tunability of the carriers.Strontium titanate, SrTiO−10 mbar. The Nb-doped (0.7 wt.%) SrTiO3 (111) substrate was heated by passing a direct current and the temperature was measured with an infrared pyrometer. The monophased (4 × 4) reconstructed surface was prepared by Ar+sputtering (1 kV / 10 μA) for 12 minutes followed by annealing in oxygen with the pressure of 3 × 10−6 mbar at 1000 °C for 1 hour. Then the (6 × 6) reconstruction was formed by depositing 1.1 monolayer  Ti atoms on (4 × 4) at 1000 °C with oxygen pressure of 3 × 10−6 mbar3(110) surface according to the reconstruction evolution behavior upon the surface metal cation concentration3(111) film was grown by co-evaporating Sr and Ti under an oxygen pressure of 3 × 10−6 mbar with the substrate temperature of 1000 °C, followed by in situ annealing at 400 °C with oxygen pressure of 5 × 10−3 mbar for 3 hours. The cross-sectional microstructure of the film was characterized by high-resolution transmission electron microscopy (HRTEM) (FEI Tecnai G2 F20). The dielectric performance of the film was measured by a microampere meter (Agilent B2901A) that provides the gate voltage, and a lock-in amplifier (SR830) that obtains the capacitive reactance in the measurement circuit with the test signal of 20.14 Hz/1 mV at 6 K.The experiments were carried out in oxide MBE system equipped with a scanning tunneling microscope (STM). The base pressure was better than 1 × 103(110) surface3(111) films due to the possibly different adhesion coefficients of metals. It has been reported that the SrTiO3(111) surface shows a series of reconstructions that evolve upon the cation concentration, e.g., a monophased (4 × 4) can be changed into (6 × 6) by depositing ~1.1 ML Ti on the surface and the transformation is totally reversible by depositing the same amount of Sr on (6 × 6)3(111) films to optimize the cation stoichiometry. In the current work, we prepare a monophased SrTiO3(111)-(6 × 6) substrate surface and basically keep it unchanged all through the film homoepitaxial growth by adjusting the temperatures of Sr and Ti sources with RHEED patterns as the feedback control signal.Although the deposition rates of Sr and Ti sources have been calibrated on SrTiO3(111) film is deposited with the substrate temperature at 1000 °C and oxygen pressure at 3 × 10−6 mbar. And the temperatures of Sr and Ti sources are initially set at 420 °C and 1450 °C, respectively. The intensity increase of RHEED (01) diffraction spot can be sensitively observed  can be determined by S is the area of the electrode and e is the unit charge. n on VG - Δn is ~4.5 × 1012/cm2 with the gate voltage as low as 25 mV. It has been reported that dopants in SrTiO3 might be redistributed due to high-temperature annealing−6 mbar at 1000 °C for 6 hours followed by annealing in oxygen with the pressure of 5 × 10−3 mbar at 400 °C for 3 hours . As shown in the inset of The SrTiOn of SrTiO3(111) thin film on Nb-doped substrate, we reduce the amount of residual oxygen vacancies (VOs) in the film by annealing at 400 °C in a tube furnace with oxygen flow at ~1 bar for 16 hours. As shown in n can be tuned in the range of 1.7 × 1013/cm2 by VG lower than 120 mV [ex situ annealing leads to the formation of an amorphous layer on the film, which seriously destroys the atomically well-defined surface as characterized by STM. Additionally the amorphous layer has a lower dielectric constant than SrTiO3 and introduces a small serial capacitor to the measured back gate structure. As the consequence, both of the total capacitance and dielectric constant are deteriorated in an uncontrolled way.In order to improve Δn 120 mV . It shoun can be enhanced by increasing the film thickness. In a thick insulating layer, defects of holes are difficult to line up to form the conducting channels. Therefore the breakdown field of a 50 nm thick film is significantly increased to 33 kV/cm [3(001) films with the thickness of several hundreds of nanometers3233G = 170 mV, the maximal Δn reaches 1.9 × 1013/cm2. The estimation of the dieletric performance of even thicker films can be made by a first-order appoximation. For example, the breakdown field of the 100-nm film could be expected as ~95 kV/cm, with ε of about 1300 and the maximal Δn of 6 × 1013/cm2 (VG = 950 mV). In such a way, the atomically well-defined surface of SrTiO3(111) film is maintained, facilitating the following epitaxial growth of other quantum materials.Alternatively, Δ33 kV/cm . The rel3(111) thin film on Nb-doped substrate by MBE. The growing surface is kept reconstructed to compensate the surface polarity and thus guarantee the layer-by-layer growth mode. And determined by the surface cation concentration, the formation of different reconstruction phases can be monitored by RHEED, providing the sensitive feedback signal for the optimization of chemical stoichiometry in real-time during film growth. Besides the atomically well-defined surface microstructure, the films show high dielectric performance that allow the modulation of carriers density in the range of 2 × 1013/cm2 with the back gate voltage lower than 0.2 V. The film provides an ideal platform for the epitaxial growth of novel quantum materials as well as the control of electronic properties in their device structures.We grow high-quality homoepitaxial SrTiOHow to cite this article: Liang, Y. et al. Homoepitaxial SrTiO3(111) Film with High Dielectric Performance and Atomically Well-Defined Surface. Sci. Rep.5, 10634; doi: 10.1038/srep10634 (2015).


All levels of these three configurations in both spectra have been established. There are 77 lines in Os VII and 71 lines in Ir VIII classified. The parametric least squares fitting calculations are used to interpret both spectra. The 6s2S1/2–6p2P1/2,3/2 transitions in Ir IX have also been identified.The spectra of osmium and iridium were photographed in the 300 Å to 1600 Å region on a 3 m normal incidence spectrograph using a triggered spark source. The (5 They belong to the Yb I isoelectronic sequence, which has been studied through Re VI [d-subshell ionic spectra.The ground configuration of the seventh spectrum of osmium (Os VII) and the eighth spectrum of iridium (Ir VIII) is 5gh Re VI –5. The eThe spectra of osmium and iridium in the 300 Å to 1600 Å wavelength region were excited in a triggered spark discharge and photographed on the 3 m normal incidence spectrograph at St. Francis Xavier University. It is equipped with a holographic grating having a line density of 2400/mm and a plate factor of 1.385 Å/mm in the first order. Osmium or iridium powder was packed into a cavity on the tip of a pure aluminium electrode, which served as the cathode. The anode was a pure aluminium electrode. In later exposures both electrodes contained the sample material. The edges of the electrodes were considerably tapered to avoid low melting point aluminium flowing inwards and blocking the high melting point sample material from getting into the discharge. The electrode gap was set between 2.5 mm to 3 mm. The charging potential was provided by a low inductance 14.3 µF capacitor bank. The discharge conditions were varied primarily by changing the number of turns in a series inductance coil. The charging potential was kept at 4 kV to 5 kV. The lines arising from different ionization stages could thus be reliably discriminated. The exposures above 500 Å were taken with Kodak SWR platesThe strongest lines in the Os VII and Ir VIII spectra appeared on the spectrograms as full length images, stretching from anode to cathode. The weaker lines were polar, stretching from the cathode to the middle of the spark gap. We used the length of the lines for roughly estimating their relative intensities.d2, 5d6s, and 5d6p [d2–5d6p array lies in the region 380 Å to 580 Å and 330 Å to 510 Å respectively, and the 5d6s–5d6p arrays lay in the regions 850 Å to 1330 Å and 800 Å to 1200 Å respectively. These arrays could be easily identified on the plates because of the good excitation separation. It was also noticed that the 5d2–5d6p array was much stronger than the 5d6s–5d6p array for both spectra.From fitted calculations of the isoelectronic spectra from Yb I to Re VI for the three configurations 5and 5d6p –5, we coand 5d6p .) Nonreland 5d6p  with the−1 of Os VII lines from those predicted with the final level values is 1.5, and for Ir VIII lines it is 1.6.With these predictions as a guide we classified 77 lines of Os VII given in d2 and 5d6s even parity configurations and all twelve levels of the 5d6p odd parity configuration for both Os VII and Ir VIII have been established and are listed in LS coupling. The standard deviation between calculated and observed levels for the even configurations of Os VII and Ir VIII are 114 cm−1 and 124 cm−1, and for the odd configuration 354 cm−1 and 336 cm−1, respectively. One can unambiguously assign LS designations to all the levels of even parity for both ions. However, for the odd parity levels none is predominantly 1D2 or 3D3. The same was also observed in Re VI [d2, 5d6s and 6s2 configurations which improved the fit to some extent. The parameters used in Os VII and Ir VIII are given in G1(dp) and G3(dp) parameters in the 5d6p configuration in both spectra were fixed at their HF ratios in the iteration process. When they were not linked the fits improved, giving standard deviations of 222 cm−1 and 237 cm−1, respectively, but the G3(dp) scaling factors were 0.516 and 0.564, respectively, with almost 12 % uncertainty on their values.All 13 levels of the 5d2–5d5f transition array in Os VII and Ir VIII has not been investigated in this research. These transitions lay between 330 Å to 397 Å in Re VI [d2+5d6s)–5d6p transitions. The corresponding transitions in Os VII and Ir VIII are below 300 Å. We intend to undertake this work shortly.The 5s2S–6p2P3/2,1/2 transitions in the Yb II sequence from Yb II to Os VIII but did not identify them in Ir IX or in the higher members. Our plates show these lines as well as the six Ir IX lines of 5d–6p and 5d–5f identified in Ref. s–6p lines of Ir IX were predicted to be at 773.5 Å and 1038 Å by extrapolation of the isoelectronic sequence (see Kaufman and Sugar  identifience see . On examence see  the line


We found that long-term exposure to elevated CO 2 emissions, is predicted to affect the physiological performance of many marine species. Recent studies have shown substantial reductions in aerobic performance in some teleost fish species, but no change or even enhanced performance in others. Notably lacking, however, are studies on the effects of near-future CO2 conditions on larger meso and apex predators, such as elasmobranchs. The epaulette shark (Hemiscyllium ocellatum) lives on shallow coral reef flats and in lagoons, where it may frequently encounter short-term periods of environmental hypoxia and elevated CO2, especially during nocturnal low tides. Indeed, H. ocellatum is remarkably tolerant to short periods (hours) of hypoxia, and possibly hypercapnia, but nothing is known about its response to prolonged exposure. We exposed H. ocellatum individuals to control (390 µatm) or one of two near-future CO2 treatments (600 or 880 µatm) for a minimum of 60 days and then measured key aspects of their respiratory physiology, namely the resting oxygen consumption rate, which is used to estimate resting metabolic rate, and critical oxygen tension, a proxy for hypoxia sensitivity. Neither of these respiratory attributes was affected by the long-term exposure to elevated CO2. Furthermore, there was no change in citrate synthase activity, a cellular indicator of aerobic energy production. Plasma bicarbonate concentrations were significantly elevated in sharks exposed to 600 and 880 µatm CO2 treatments, indicating that acidosis was probably prevented by regulatory changes in acid–base relevant ions. Epaulette sharks may therefore possess adaptations that confer tolerance to CO2 levels projected to occur in the ocean by the end of this century. It remains uncertain whether other elasmobranchs, especially pelagic species that do not experience such diurnal fluctuations in their environment, will be equally tolerant.Ocean acidification, resulting from increasing anthropogenic CO The aim was to provide insight into the physiological parameters that may underpin changes in metabolic performance and sensitivity to hypoxia in this species. We hypothesized that H. ocellatum can physiologically tolerate elevated CO2 because it routinely experiences daily reductions in environmental O2  to elevated CO2 may negatively affect metabolic rate and hypoxia tolerance.We exposed ental O2  and probHemiscyllium ocelatum) were collected from the northern Great Barrier Reef by Northern Barrier and Cairns Marine  and transported to James Cook University (JCU). Five to six individuals were placed in each of six 700 l tanks in a recirculating seawater system. Individuals were measured  to ensure an equal distribution of sizes among tanks. Unique fin clips along the margins of pectoral, pelvic and dorsal fins were used for individual identification. Shelter was provided in the form of PVC pipe sections placed within each tank. Food was provided once every 24 h and consisted of 4% of shark biomass per tank in raw prawn meat. There was no indication that any individuals or treatment groups were eating less than this amount throughout the duration of the study. Sharks were acclimated to laboratory conditions for at least 4 weeks prior to commencing CO2 treatments.Epaulette sharks (2 treatments: control (∼390 µatm); medium (∼600 µatm); and high (∼880 µatm). Carbon dioxide levels were achieved and maintained by CO2 infusion of seawater in 3000 l sumps attached to each recirculating seawater system. The pHNBS  levels were set to match target CO2 concentrations and maintained using a CO2-infusing system . If the pH rose above the set point, an electronic solenoid initiated the system to deliver a steady stream of CO2 into a diffuser within the corresponding sump. Carbon dioxide-equilibrated seawater from each system was delivered to two replicate 700 l tanks (∼25 l min−1) per treatment. Each tank contained five or six sharks, as described above. This central approach of pH manipulation allowed for stability in seawater pH and PCO2 within the holding tanks. Tanks were covered with transparent plastic sheeting to reduce CO2 loss to the atmosphere.The experimental system comprised three 8000 l recirculating seawater systems, each set to simulate one of the following three CONBS was measured daily  in each tank to ensure that it remained within ±0.05 of desired levels. Temperatures were also measured daily and maintained at 28.5°C by automated heater/chillers attached to each seawater system. Salinity and alkalinity were measured on a weekly basis. Total alkalinity (TA) was estimated using Gran titrations and certified reference materials . Average seawater PCO2 was calculated using these parameters in CO2SYS  were determined for sharks following 60–68 days of exposure to control (n = 10), medium (n = 12) and high (n = 11) CO2 conditions and a 48 h fasting period using an intermittent-flow respirometry system with purpose-built respirometry chambers. Animals were transferred individually into the cylindrical 11 or 15 l respirometry chambers  submerged in a temperature-controlled aquarium (28.5°C) within each animal's respective experimental CO2 conditions and habituated to the chamber for 12 h before oxygen consumption measurements commenced. Submersible pumps were fitted to each chamber to supply a continuous water flow  from the surrounding water bath through the chambers. During respirometry trials, a digital relay timer  was used to stop water flow for 15 or 20 min and then resume flushing for 15 min over a total period of 12 h. The intervals of interrupted water flow were short enough to ensure that oxygen within the chambers did not fall below 80% saturation at any time, while flush periods were long enough to eliminate accumulation of metabolic CO2 and allow water oxygen levels to return to 100% saturation  was connected to each respirometry chamber to recirculate water continuously within the chamber, thus ensuring complete mixing and homogeneous water PO2 (PWO2). Contactless spots (2 mm) with oxygen-sensitive REDFLASH dye were adhered to the inside of glass tubes connected to the recirculating pumps on each respirometer. These spots were then linked to a Firesting Optical Oxygen Meter  via 5 m fibre-optic cables to record continuously (0.5 Hz) the temperature-compensated O2 concentration (in milligrams per litre) of the water within each chamber over the 12 h period of time. The 0 and 100% oxygen levels of the Firesting oxygen meter were calibrated using 0 and 100% air-saturated seawater. At the end of each trial, the wet mass was taken for each shark [232.47 ± 117.98 g (mean ± SD)] prior to release back to experimental holding conditions.Resting Oturation . A seconṀO2Rest measurements, sharks were permitted to recover in their respective CO2 treatment conditions for ∼3 weeks. Then, the same respirometers used to determine ṀO2Rest were used to determine the critical oxygen tension (Pcrit) for the same sharks exposed to control (n = 9), medium (n = 12) and high CO2 (n = 10). By this point, sharks would have been exposed to their respective experimental conditions for 85–92 days. Prior to measurements, sharks were fasted for 48 h before being introduced to the cylindrical 11–15 l respirometry chambers. Then, the ṀO2 of each animal was monitored for a minimum of 4 h using an intermittent flush cycle (15 min flush–15 min closed) so that stable ṀO2Rest was achieved prior to commencing the hypoxia experiment. The respirometers were then sealed by turning off flush pumps and closing previously installed ball-valves downstream of the flush pumps. Oxygen levels in the chamber were monitored continuously (0.5 Hz) and allowed to decrease to at least 0.8 mg l−1 to ensure that the critical oxygen tension for each individual was recorded (based on estimates from 2 that occur when using closed respirometry for a short period of time have been shown previously to have no effect on Pcrit in fish (2 levels within each respirometer could quickly return to normoxic conditions (100% air-saturated seawater).Upon completion of Pcrit measurements, animals were returned to their treatment tanks to recover for ∼1 week. After this time, blood was sampled from sharks exposed to control (n = 8), medium (n = 10) and high (n = 8) CO2 conditions by inserting a 23 gauge needle posterior to the cloaca into the caudal vein and collecting the blood (<1% of body volume) into heparinized syringes. Animals were then euthanized by severing the spinal cord using the method described by ®  with 10 µl of whole blood and was reported as grams per 100 ml using a calibration curve according to g and calculated as the ratio of packed red blood cells to total blood volume (as a percentage). Both [Hb] and Hct were used to calculate the MCHC. The spleen was dissected from each shark and weighed to the nearest 0.001 g. The SSI was calculated as the ratio of the spleen to body mass (as a percentage). Plasma was flash frozen immediately in liquid nitrogen and then stored at −80°C until analysis for [HCO3−] via colorometrically linked enzyme assay and for [Na+], [K+], [Cl−] (1:1 dilution with deionized water) and [urea] (1:19 dilution with deionized water) via ion-specific electrodes . Heart, brain and red muscle samples were also collected and frozen in liquid N2 for citrate synthase enzyme analysis according to m EDTA, 0.1% Triton X-100, 0.2 mm dithiothreitol and 50 mm Hepes (adjusted to pH 7.4) and stored at −80°C. The citrate synthase assay buffer contained (mm): 20 Tris (pH 8.0), 0.1 5,5-dithiobis (2-nitrobenzoic acid) and 0.3 acetyl-CoA. The reaction was initiated by the addition of 0.5 mm oxaloacetate, and absorbance was measured for 5 min at 412 nm. Control samples were assayed without oxaloacetate to control for background hydrolase activity.Following ṀO2Rest (in milligams per kilogram per hour). To do this, the average of the shallowest 10% of slopes [change in O2 concentration over a period of 15–20 min (in milligams of O2 per litre per second) in between flushing cycles] was determined for each individual shark. From this, the appropriate proportion of background O2 consumption, which was measured 2–3 h before and after each trial for each respirometer and assumed linear, was subtracted. This value was then multiplied by the volume of the respirometer , all of which was divided by the mass of the fish (in kilograms). Respirometers were cleaned daily to ensure that background  respiration did not exceed 10% of the ṀO2Rest of the sharks. Means and SEM for ṀO2Rest were calculated for each of the three CO2 treatments.Raw text files created for the Firesting recordings were imported offline into LabChart version 6.1.3 , which was used to analyse data. A modified version of equations from Pcrit. Again, ṀO2Rest was calculated for each shark from the shallowest 10% of slopes that were recorded prior to sealing the respirometer. Then, the mean slope for every 5 min period of time while the respirometer was sealed was extracted , and ṀO2 values were calculated from those slopes. To determine Pcrit, all ṀO2 values were plotted against the oxygen concentration within the chamber for each shark. A horizontal (regression) line was fitted to the mean ṀO2Rest prior to sealing the respirometer. Then, a linear regression was applied to all of the points that consecutively fell below ṀO2Rest once the respirometer had been sealed. The point at which both regression lines intersected was reported as the critical oxygen tension or Pcrit (in milligams of O2 per litre) for that individual  or mean Pcrit (in milligams of O2 per litre). As there was no significant effect of tanks on either parameter, data from the two tanks within treatments were pooled for further analyses. ANCOVA was used to compare ṀO2Rest among the three CO2 treatments, with standard length as a covariate. To compare Pcrit among treatment groups, a robust regression analysis was performed with standard length as a covariate. Robust regression analysis was chosen over ANCOVA for Pcrit analysis due to potential outliers that could otherwise be solely responsible for significant outcomes. The removal of such outliers was rejected owing to the relatively small sample size. Instead, robust regression weighs values differently based on their chance of being an outlier. Hence, the further away a single data point was from the mean, the less influential it became for the statistical outcome of the analysis. There was no interaction between the main effect (CO2) and the covariate in either analysis; therefore, to increase statistical power, the analyses were run again without this term included. Standard length was not included in haematological and tissue data analyses because it had no significant effect on the outcomes. ANOVAs were then used together with Holm–Sidak post hoc tests to compare haematological and tissue parameters between animals acclimated to control, medium and high CO2 conditions. Statistical significance was accepted when P < 0.05. All analyses were carried out using S-Plus .Nested ANOVA, with holding tanks nested within COṀO2Rest values between CO2 treatment groups . However, ṀO2Rest depended on the standard length of the individuals, with larger animals having a higher ṀO2Rest than smaller animals . However, standard length had a significant effect on the Pcrit of individuals , heart  or brain . We observed a decrease, although non-significant, in the SSI in sharks exposed to both medium and high CO2, suggesting that splenic contraction(s) may have occurred at some point during the CO2 exposure period. Periodic splenic contractions could also increase the proportion of immature RBCs in circulation, which could explain the slight increase in MCHC without significant changes in Hct. The temporal scale of splenic RBC release and subsequent increases in erythropoietin, the glycoprotein responsible for regulating RBC numbers, is well understood for teleosts  and Na+–K+-ATPase at higher densities. Given the relationship between bicarbonate availability and synthesis of urea (the predominant osmolyte used by most elasmobranchs), acid–base compensatory mechanisms could have affected [urea] and therefore the efficiency of osmoregulatory pathways  or alter chemical equilibrium constraints in the blood over longer periods to maintain oxygen transport.Plasma [HCO2 exposure, there was an unexpected pattern of mass-specific metabolic rates, with larger sharks exhibiting higher mass-specific metabolic rates than smaller sharks. This contradicts the usual pattern exhibited by ectotherms, but may be related to their feeding patterns. For example, we examined sharks ranging in size from ∼20 to 50 cm. However, we used a set 48 h fasting period prior to determining oxygen consumption rates and prior to blood and tissue sampling because of their small size and benthic lifestyle and previous feeding patterns while in captivity. It could have been that 48 h was sufficient fasting time for the smaller animals but not for the larger animals of that size range ; the School of Earth and Environmental Science ; AIMS@JCU ; and the Australian Research Council Centre of Excellence for Coral Reef Studies .


Quantum switch is a primitive element in quantum network communication. In contrast to previous switch schemes on one degree of freedom (DOF) of quantum systems, we consider controlled switches of photon system with two DOFs. These controlled photon switches are constructed by exploring the optical selection rules derived from the quantum-dot spins in one-sided optical microcavities. Several double controlled-NOT gate on different joint systems are greatly simplified with an auxiliary DOF of the controlling photon. The photon switches show that two DOFs of photons can be independently transmitted in quantum networks. This result reduces the quantum resources for quantum network communication. Photonic schemes are very important in quantum information processing because of their superiority on the speed2357Recently strong quantum light-matter couplings in photonic nanostructures can produce effective interactions between photons, which have leaded some remarkable phenomena such as the photon blockade11131718212226272829303132In comparison to these results using one degree of freedom (DOF)11121314151617181920212223242526272829303132353740414243444647In this paper, we consider phononic switching schemes of two DOFs of photon states using the optical circular birefringence of a one-sided QD-cavity system. Most previous results262728293031324950515254555657585926272829303132a, b and c, shown in a and b may be swapped if the qubit c is a and b are unchanged. The hyper-photons a and b with the polarization and spatial-mode DOFs are considered in this paper. Our motivation is to manipulate them simultaneously. Thus these DOFs may be applied as independent qubits in quantum information processing. Different from the detailed decomposition of the Toffoli gate with six CNOT gates545556575859The primitive block of the proposed reconfigurable quantum switch is the controlled 2 × 2 quantum swapping gate626272829303132To complete controlled quantum switches of hyper photons, the following optical property and quantum dot system (QD) are used for our schemes4849545556575859κs and κ should be changedωc = ωc − ω and Δωe = ωe − ω. ωc, ωe and ω are the frequencies of the cavity mode, the input probe light, and the dipole transition, respectively. g is the coupling strength between the cavity and dipole. ς, κ, and κs are the decay rates of the dipole, the cavity field, and the cavity side leakage mode, respectively. The reflection coefficient in if the dipole stays in the ground state at most of the time49545556575859g = 0)49ω and ωc, the reflection coefficients can satisfy if the QD is uncoupled from the cavity  on the polarization DOF of two photons a and b, the joint system of the photons a and b becomesFrom the c is in the state c is in the state c and an auxiliary spin e1 in the state CPS in b and the spatial mode DOF of the photon c], the joint system of three photons a, b, and c is changed intoFrom c from the spatial mode c2 pass through the cPS1, the cavity Cy1 [with e1], and cPS2 from the path ①. The state e1 are changed intoAnd then, let the photon which may be transformed intoW on the spin e1. Now, the photon a from the spatial mode a1 passes through the H1, cPS3, the cavity Cy1, cPS4, and H3 from the path ②, while the photon a from the spatial a2 passes through the H3, cPS5, the cavity Cy1, cPS6, and H4 from the path ③. The the joint system by performing a Hadamard operation e1 under the basis Z is performed on the photon c from the spatial mode c2 for the measurement outcome Moreover, measures the spin CPP on the polarization DOF of the photons a and b, Furthermore, after performing the CNOT gate c under the basis cBS2, cPS7, cPS8 and four single photon detectors. If the photon c is detected at Finally, measures the photon Z is performed on the polarization DOF of the photon a and b for a and b have not been switched, i.e., the Toffoli gate is not fired. Otherwise, the photon c is detected at where one phase flip Z is performed on the polarization DOF of the photon a and photon b for a and b have been switched, i.e., the Toffoli gate is fired. the controlled quantum switch on the polarization DOF of two photons has been realized up to the specific assumption of the controlling photon c.where one phase flip a and b. The CNOT gate CSS in the a and ba and b intoSimilarly, the d is d and an auxiliary spin e2 in the state CSS is performed on the photons b and d to getIf the polarization DOF of the controlling photon d from the spatial mode d2 pass through the cPS1, the cavity Cy2 [with e2], and cPS2 from the path ①. e2 are changed intoLet the photon W performed on the spin e2. Now, the cBS1 is used to realize a Hadamard operation on the spatial mode DOF of the photon a. And then, the photon a from the spatial mode a2 passes through the cPS3, where the reflected part passes through the cavity Cy2 from the path ② while the transmitted part passes through the X1, the cavity Cy2, and X2 from the path ③, all of them combined into one photon from the cPS4. Thus after a Hadamard operation a passing through the cBS2. The spin e2 is disentangled by measuring it under the basis after the output photon Z is performed on the photon d from the spatial mode d2 for the measurement outcome CSS [on the spatial mode DOF of the photons a and b] may change where the Pauli phase flip d under the basis MPD in the d is detected at Finally, measure the controlling photon I is performed on the polarization DOF of the photon a from the spatial mode a2 and −I is performed on the polarization DOF of the photon b from the spatial mode b2 for a and b have not been switched, i.e., the Toffoli gate is not fired. If the photon d is detected at where the phase operation −a and b have been switched, i.e., the Toffoli gate is fired. Therefore, the controlled quantum switch of the spatial mode DOF of two photons has been realized up to the general assumption of the controlling photon d.with the similar recovery operations for a and b. The initial states of four photons a, b, c and d are same to these defined in the Derived from the circuit in the CPS on the polarization DOF of the photon a and the spatial mode DOF of b  are only performed on the two-qubit states with different basesCPP,CPS,CSP, and CSS] on different DOFs of the photons x and y lead to the same transformation on a four-dimensional space defined by the matrixThe general fidelity is defined by S1 and S2 have realized the same double-controlled NOT gate shown in a are omitted. Generally, the high fidelity may be achieved from the strong coupling strength, the low side leakage and cavity loss rate κs/κ. The strong coupling strength g/(κ + κs) has been raised to 2.4 by improving the sample designs, growth, and fabrication58g/(κ + κs) ≈ 2.4 with κs/κ ≈ 0, the fidelities of hyper photon switches are greater than 97.75%. In experiment, the side leakage and cavity loss rate have been reduced to κs/κ ≈ 0.7 with g/(κ + κs) ≈ 157The differences are the spaces defined by the input qubits. The third is that the average fidelities are evaluated from the expectations of the initial states. Thus, the input qubit of the spatial DOF has no difference with the qubit of polarization DOF of each photon. The last is that the subcircuits In conclusion, we have investigated the possibility of photon switches based on two DOFs of photon systems. By using several deterministic CNOT gates on the polarization and spatial mode DOF of a two-photon system and the simplified Toffoli gates on several three-photon systems, we design several controlled photon switches. Compared with the same DOF of photon switches2627282930313226272829303132N × N quantum Benes network is defined recursively shown in N−1 stages of 2 × 2 quantum switches, with each stage having no more than N/2 2 × 2 switches. Similar to the classical Benes network, the quantum Benes network is rearrangeable non-blocking, i.e., for any permutation π∈ SN, there exists a setting of the 2 × 2 switches such that π can be realized by the network. The simplest classical routing algorithm is the looping algorithm6O(N log N). However, previous route-finding algorithm has not reduced the complexity of distinct pathes. With some pre-coding, a modified algorithm is presented. For N input photons 1,2, · · ·, N, there are N possible outputs. The outputs may be described as π. Label all lines using li,j under the matrix order. i denotes the input number while j denotes the number of links from left to right. For each switch, there are four possible lines. Two lines li,j and lj,j for each pair  denote links for unchanged transmissions. Lines li,j for each pair  denote links for crossly transmissions.In order to realize general quantum network transmission, the primitive 2 × 2 quantum switch may be extended to multiple inputs. Quantum switching networks are analogs of classical switching networks in which classical switches are replaced by quantum switches. These networks are used to switch quantum data among a set of quantum sources and receivers. Similar to classical switch networks6Algorithmπ, where each input i is mapped to output π(i), i = 1, · · ·, N. Let S1={π(i)|π(i1) < π(i2) if i1 < i2} and (1) The permutation map is given by S1 in parallel (upward if π(i) > i or downward if π(i) < i, signal by continuing straight across the planar network using π(1)−1 stitches, and then forward to last stages. Record the routes by their lines.(2) Route all the inputs in (3) Delete the completed paths and associated switches  from the network see .(4) Move the separated upper right corner triangle down and left to reconstruct the planar topology see .(5) The remained  2–4 see .i-th route, if there are ni associated switches used by previous i-1 routes, it should be connected in order with previous i-1 routes [see (6) Finally, reconstruct all routes with original links, sequentially. For the utes see .S1, all these routes have no common links. In the second time, π(3) and π(5) have common links (π(3) > π(5) and 3 < 5). In the third time, This route-finding algorithm takes only three times in comparison to the seven times using the looping algorithm6Previous results are mainly depended on one DOF, such as the polarization logic gates using the spatial-mode DOF as the assistant2164How to cite this article: Luo, M.-X. et al. Controlled Photon Switch Assisted by Coupled Quantum Dots. Sci. Rep.5, 11169; doi: 10.1038/srep11169 (2015).


The method gives access to a range of α-fluorovinyl thioethers, some in high stereoselectivity with the Z-isomer predominating over the E-isomer. The α-fluorovinyl thioether motif has prospects as a steric and electronic mimetic of thioester enols and enolates, important intermediates in enzymatic C–C bond forming reactions. The method opens access to appropriate analogues for investigations in this direction.A new method for the preparation of α-fluorovinyl thioethers is reported which involves the hydrofluorination of alkynyl sulfides with 3HF·Et Broad peaks corresponding to the excess 3HF·Et3N reagent were present. BF4− is known to be an inherently inert, non-nucleophilic counter ion; in the case of TiF4, [TiF6]2− was the only species present in solution, and we were unable to detect any penta-coordinated [TiF5]− species. It has been reported that an excess of hydrofluoric acid positions the equilibrium between [TiF5]− and [TiF6]2− in favour of the latter [6]2− is rather unreactive 2− and also an excess 3HF·Et3N.e latter . Moreovereactive , similar3N by sequestering fluoride ions as relatively unreactive metal fluorides; thus, the alkynyl sulfides are activated by protonation possibly through an intermediate such as A as illustrated in cis stereoselectivity is consistent with the attack of an intermediate such as A from the less hindered face, opposite to the R1 substituent (In light of these observations, our working hypothesis is that the Lewis acid acts to increase the acidity of the 3HF·Etstituent .3N and requires activation using BF3·Et2O or TiF4. The reactions display moderate to good stereoselectivity in favour of the Z-hydrofluorination product, and this opens the way forward for making appropriate analogues as potential steric and electronic mimetics of thioester enols and enolates relevant to particular enzymatic transformations.In summary, we have developed a mild method for the synthesis of α-fluorovinyl thioethers. The method involves the hydrofluorination of alkynyl sulfides by 3HF·EtFile 1Experimental part and NMR spectra of synthesised compounds.