This paper presents the formulae and finite element analysis models for predicting the Modulus of Elastic (MOE) and Modulus of Rupture (MOR) of Cathay poplar finger-jointed glulam. The formula of the MOE predicts the MOE of Cathay poplar glulam glued with one-component polyurethane precisely. Three formulae are used to predict the MOR, and Equation (12) predicts the MOR of Cathay poplar glulam precisely. The finite element analysis simulation results of both the MOE and MOR are similar to the experimental results. The predicted results of the finite element analysis are shown to be more accurate than those of the formulae, because the finite element analysis considers the glue layers, but the formulae do not. Three types of typical failure modes due to bending were summarized. The bending properties of Cathay poplar glulam were compared to those of Douglas fir glulam. The results show that Cathay poplar glulam has a lower stiffness, but a marginally higher strength. One-component polyurethane adhesive is shown to be more effective than resorcinol formaldehyde resin adhesive for Cathay poplar glulam. This study shows that Cathay poplar has the potential to be a glulam material in China. Modern wooden structures have been used in many areas around the world. Glued-laminated timber (glulam) is a type of engineered wood product that can preserve the natural beauty of the source wood during construction ,2. StrucPopulus cathayana) is one of the most abundant, fast-growing species in northern China and is cold resistant, fast growing, straight grained, medium and evenly textured and easy to manufacture. Cathay poplar is thus an excellent material for construction components [Cathay poplar  is an efficient research method used in the wooden materials field. By establishing a finite element analysis model and post-processing, visual predictions can be obtained without specimen failures. In 1980, Foschi and Barrett put forward the Foschi-Barrett simulation model, which used the Monte Carlo method, to predict the Modulus of Rupture (MOR) of glulam. The Ala Tabiei  model siThe formula model is also commonly used to make numerical simulation of glulam. Kohler , Fink 1,17 and JThe Modulus of Rupture (MOE) and MOR are both paramount properties of glulam. Four formulae were derived, and finite element analysis models were established to predict the MOE and MOR of Cathay poplar finger-jointed glulam. In addition, the bending properties of Cathay poplar glulam were examined and compared to those of Douglas fir glulam. A comparison of the test and simulation results was also performed.Cathay poplar was obtained from the Beijing Longshun Wood Market, Beijing, China. Douglas fir was imported from North America . The moisture content of the Cathay poplar and the Douglas fir ranged from 9% to 12%. The physical and mechanical properties of the Cathay poplar and Douglas fir lumber are shown in Visual grading and the MOE test method were used in this study. A total of 52 pieces of Cathay poplar sawn lumbers with dimensions of 60 (width (W)) mm × 800 (length (L)) mm was tested, where half of the pieces were 20 mm thick and the other half were 30 mm thick. The lumber was graded based on GB/T  26899-2011 . The conGlulam specimens were manufactured based on GB/T 26899-2011. All of the glulam specimens were 3000 (L) mm × 60 (W) mm × 120 (T) mm. The length of finger joints was 21.5 mm, and the width was 8.0 mm. The distribution of finger joints in glulam satisfies the construction requirement of glulam. The positions of finger joints were at least 30 cm away from each adjacent layer.The specimen parameters are shown in i.e., bending test Method A) was performed based on GB/T 26899-2011 at a loading speed of 8 mm/min. An LVDT  sensor was set at the midspan of each specimen.  and sugi finger-jointed laminae. In these studies, to examine the optimum adhesive condition in the finger-joint part that influences the strength properties of the large-scale finger-jointed laminae, the block shear tests with block specimens that assumed the finger-joint part and glued under various adhesive conditions was performed. In conclusion, for glulam with good strength properties, the evaluation of finger-joint properties is important. In addition, Frese [In terms of experimental research, Ohuchi ,25 came n, Frese  tested tIn terms of the glulam strength model, Frese  put forwTherefore, based on the above research, the following conclusions were proposed.Shear failure of the finger joint led to the failures of PR4 and PR6. The bending strengths of PR4 and PR6 were indicative of the bonding strength of a finger joint with RF, but did not fully describe the mechanical properties of Cathay poplar.Shear failure of the finger joint and splitting of timber caused the failure of PO6. The bending strength of PO6 was indicative of both the bonding strength of a finger joint with PU and the mechanical properties of Cathay poplar. Compared to the RF, the Cathay poplar glued with PU performs better.Splitting of timber resulted in the failures of DO4 and DO6. The bending strengths of DO4 and DO6 were indicative of the mechanical properties of Douglas fir, but did not fully describe the bonding strength of a finger joint with PU.The load displacement curves of the mean value of the specimens from each series are shown in Firstly, a comparison of the different wood species was performed. The MOR of PR6 was 2.4% higher than that of DO6, and the MOE of DO6 was 70.6% higher than that of PO6. In this study, the Cathay poplar glulam had a lower stiffness, but a marginally higher strength compared to those of the Douglas fir glulam. The ultimate tensile strain of PO6 was 0.0053, and the maximum compressive strain was 0.0063; these values were both higher than those of Douglas fir glulam.Secondly, a comparison of the different adhesives was performed. Based on the experimental results, the MOR of PO6 was 2.6% higher than that of PR6, and the MOE of PR6 was 32.9% higher than that of PO6. For the Cathay poplar glulam, the PU is shown to be more effective than the RF.Lastly, a comparison of the different numbers of layers was performed. The MOR of PR6 was 1.2% higher than that of PR4, and the MOR of DO6 was 6.4% higher than that of DO4. The MOE of PR6 was 14.3% higher than that of PR4, and the MOE of DO6 was 4.3% higher than that of DO4. With the same thickness, the bending strength increased as the number of layers increased.The bending strength, the shear strength and the deflection of the glulam specimens were checked.M and maximum shear strength V were 1.68 × 106 N·mm and 2000 N based on the principle of the balance of force and moment, respectively. The shear diagram and bending moment diagram are shown as The load of a room was assumed to be carried by sample PO6. Based on the characteristic load combination in GB 50009-2012 , the desi.e., 5%, the percentile of the sample) of the mechanical strength of the Cathay Poplar were calculated. Based on GB 50005-2003 [mf and the shear strength parallel to the grain vf were 17 and 2.4 MPa, respectively.The characteristic values . mf (17 MPa). In conclusion, PO6 achieves the required bending strength in GB 50009-2012.The value of checking calculation was 11.67 MPa, which was lower than the design value of bending strength Q is the first moment of area, which was 1.08 × 105 mm3; I is the second moment of area , which was 8.64 × 106 mm4; b is the width of the specimen, which was 60 mm; and The shearing strength was checked by Equation (4). mf (2.4 MPa). In conclusion, PO6 achieves the required horizontal shearing strength in GB 50009-2012 [The value of checking calculation was 0.42 MPa, which was lower than design value of horizontal shearing strength 009-2012 .The deflection was checked by Equation (5). The MOE of PO6 was 11,119 MPa, so the value of checking calculation was 8.14 mm, which was lower than the design value of deflection. In conclusion, PO6 satisfies the deflection requirements in GB 50009-2012 .Therefore, the bending strength, shear strength and deflection of PO6 pass the checking calculations.The MOE for bending of the Cathay poplar glulam was calculated based on that of sawn lumber using a formula that will now be described. The accuracy of the formula is also verified below.jIje = the bending stiffness of the j laminate). The bending stiffness of a glulam specimen was the sum of the bending stiffness of each laminate layer under the non-glued layers, as shown in Equation (7) [bE is the MOE of the glulam specimen; I is the section moment of inertia of the glulam specimen; and jIje is the MOE multiplied by the section moment of inertia of the j laminate , respectively.Wang and Chang  showed ttion (7) :(7)EbI=j0I is the section moment of inertia of the j-th laminate to the central plane of the glulam specimen; jA is the sectional area of the j-th laminate; and jd is the distance between the j-th laminate and the central plane of the glulam specimen.Based on the parallel axis theorem from material mechanics , the secEquation (8) was then substituted into Equation (7):The mean values of the theoretical results of Equation (9) are shown in The MOR of glulam is typically significantly better compared to that of sawn lumber due to the distribution of defects in the lumber . The MORb,gl,kf is the characteristic MOR of glulam and t,lam,kf is the characteristic value of the tensile strength of the lumber.Based on many experimental results, EN (European Norm) 1194 (Europe Standard Committee) has shown that the relationship between the MOR of the bending of glulam and the tensile strength of the lumber used is linear. A laminate coefficient λ is thus introduced and is expressed in the following two Equation:t,lam,kf. For lumber that has higher tensile properties, its laminate coefficient is smaller than lumber that has lower tensile properties. Therefore, the bending properties of glulam made of worse lumber have greatly improved compared to glulam made of better lumber.The laminate coefficient λ is inversely proportional to the characteristic value of the tensile strength of the lumber r = 0.945 and the two formulae are only suitable for glulam with a thickness of 600 mm. If the dimensions are different, the MOR should be multiplied by the volume factor k [bF is the MOR of glulam with other dimensions, b0F is the MOR of glulam with standard dimensions, 0V is the standard volume (130 mm × 300 mm × 6400 mm), V is the measured volume and k is the volume factor = 0.076 [The correlation coefficient factor k ,36,(11) = 0.076 .Based on the bending and tensile results, regression analysis is used to describe the relationship between the MOR of glulam and the tensile strength of the lumber used. The tensile strengths of the lumber mean the mean experimental values of 20 mm-thick lumber and the mean experimental values of 30 mm-thick lumber. In this formula, the tensile strength of the lumber is an independent variable, and the MOR of glulam is a dependent variable. Based on the scatter diagram drawn by Origin , the relE is the MOE for the bending of glulam and ε is the elongation of a unit length.Equation (14) was derived to describe the relationship between the MOR of glulam and the MOR of the lumber used. For symmetrical glulam, the MOR is expressed by the following Equation:Equation (8) in The mean values of the theoretical results of Equations (10), (12) and (14) are shown in The theoretical results are shown to be 28.03% higher than the corrected experimental results on average. This is probably because Equation (10) was derived based on the experimental results of European glulam, and their mechanical properties have many differences from that of Cathay poplar glulam.Equation (12) was derived based on the experimental results, and the theoretical results are similar to the experimental results. Equation (12) can predict the MOR of Cathay poplar glulam.Equation (14) shows that the error between the test and calculated values of PR4 is somewhat larger. This is because of the softening of a finger-joint bond. This deviation leads to 23.04% lower theoretical results compared to the experimental results.The MOE and MOR of Cathay poplar glulam are calculated using the finite element program ANSYS, Version 14.5. In addition, four elastic cushion blocks are set at two of the supports and two loading points to mitigate stress concentrations and to create a more accurate simulation. Based on He  and TuohThe mean values of the simulation results of the MOE for bending and MOR of Cathay poplar glulam are shown in For the MOE, the simulation results are all higher than the experimental results. The mean error of PR4 is 8.98%, while that of PR6 is 7.67%; the error of PO6 is lower (2.79%). Thus, the simulation of PO6 is more accurate than those of PR4 and PR6.For the MOR, the simulation results are all lower than the experimental results. The mean error of PR4 is −5.33%, that of PR6 is −5.39% and that of PO6 is −3.89%. Thus, the simulation of PO6 is more accurate than those of PR4 and PR6.Therefore, the simulations of the MOE and MOR of PO6 are better than those of PR4 and PR6.For the MOE, the calculation and simulation results of PO6 approach the experimental results, but the errors between the results of PR4 and PR6 are somewhat larger. Therefore, the formulae and simulation model are both suitable to predict the MOE of Cathay poplar glulam glued with PU.For the MOR, the error between the test and simulation results is small, but the error between the test and theoretical results is somewhat larger. Therefore, the results of the finite element analysis are more accurate than those of the formulae. This is probably because the glue layers were considered in the simulation models, but the formulae were derived without considering the glue layers.Based on the experiments, calculations and finite element analysis, the following conclusions can be drawn.Cathay poplar glulam has a lower stiffness, but slightly higher strength compared to Douglas fir glulam in this experiment. The ultimate tensile strain of Cathay poplar glulam glued with polyurethane is 0.0053, and its maximum compressive strain is 0.0063, both of which are higher than those of Douglas fir glulam. This study indicates that Cathay poplar has the potential to be glulam material in China. In terms of the adhesive, the MOR of six-layer Cathay poplar glulam glued with one-component polyurethane adhesive is 2.6% higher than that of six-layer Cathay poplar glulam glued with resorcinol formaldehyde resin adhesive, and the MOE of the latter is 32.9% higher than that of the former.A formula is derived to predict the MOE of Cathay poplar glulam based on the MOE of its laminates. The results indicate that the formula could predict the MOE of six-layer Cathay poplar glulam glued with one-component polyurethane adhesive. Three formulae are used to predict the MOR of Cathay poplar glulam based on the MOR and the tensile strength of its laminates. Equation (12) is suitable to predict the MOR of Cathay poplar glulam. The simulation results of both the MOE and MOR of Cathay poplar glulam are similar to the experimental results. The simulation of Cathay poplar glulam glued with one-component polyurethane is shown to be more accurate than those of Cathay poplar glulam glued with resorcinol formaldehyde resin adhesive. The error of the MOE is shown to be 2.8%, and that of the MOR is shown to be −3.9%.


Mucopolysaccharidosis type II  is an X-linked genetic disorder caused by a deficiency of iduronate 2-sulfatase (IDS), and missense mutations comprising about 30% of the mutations responsible for MPS II result in heterogeneous phenotypes ranging from the severe to the attenuated form. To elucidate the basis of MPS II from the structural viewpoint, we built structural models of the wild type and mutant IDS proteins resulting from 131 missense mutations (phenotypes: 67 severe and 64 attenuated), and analyzed the influence of each amino acid substitution on the IDS structure by calculating the accessible surface area, the number of atoms affected and the root-mean-square distance. The results revealed that the amino acid substitutions causing MPS II were widely spread over the enzyme molecule and that the structural changes of the enzyme protein were generally larger in the severe group than in the attenuated one. Coloring of the atoms influenced by different amino acid substitutions at the same residue showed that the structural changes influenced the disease progression. Based on these data, we constructed a database of IDS mutations as to the structures of mutant IDS proteins. Iduronate 2-sulfatase  is a lysosomal enzyme that catalyses the hydrolysis of sulfated esters at the non-reducing-terminal iduronic acids in the glycosaminoglycans (GAGs) heparan sulfate and dermatan sulfate. A deficiency of IDS activity results in systemic accumulation of GAGs, leading to a rare metabolic disease, mucopolysaccharidosis type II , which is also known as Hunter syndrome [Enzyme replacement therapy (ERT) involving recombinant human IDS is approved in many countries for treatment of MPS II patients. As recent studies demonstrated that ERT improved the manifestations of MPS II, especially when it was started at an early age –5, an eaThe IDS gene is located at the Xq27/28 boundary , and conAs to human IDS, no crystal structure has been reported, and a few structural models have been constructed by means of homology modeling using crystal structure information of other sulfatases including arylsulfatase A and arylsulfatase B as templates –14. In tIn this study, we built a new structural model of human IDS by means of the homology modeling and molecular dynamics methods, and predicted structural changes in IDS caused by 131 amino acid substitutions responsible for MPS II, and examined the relationship between the mutant IDS structures and the respective clinical phenotypes.IDS gene for which the MPS II phenotypes have been clearly described (67 severe and 64 attenuated). These missense mutations, the respective phenotypes, and the references are summarized in Table 1, and other missense mutations in the IDS gene that were excluded in this analysis are summarized in S1 Table.In this study, we analyzed 131 missense mutations in the zhanglab.ccmb.med.umich.edu/ I-TASSER/) [Because no IDS crystal structure has been reported, we built a model of human IDS using homology modeling server I-TASSER (TASSER/) . To takeTASSER/) . In the II were built by means of homology modeling using the wild type IDS protein model as a template. For that purpose, we used molecular modeling software TINKER [Structural models of mutant human IDS proteins responsible for MPS e TINKER , and enee TINKER . We calcTo determine the influence of each amino acid substitution on the total conformational change in IDS, the RMSD values of all atoms in the mutant IDS proteins were calculated according to the standard method . Then, aThe ASA of each amino acid residue in the structure of the wild type IDS was calculated using Stride  to detert-test, and it was taken that there was a significant difference if p< 0.05.Statistical analysis to determine the differences in the numbers of influenced atoms, the RMSD, and the ASA values between the severe MPS II group and the attenuated one was performed by means of Welch’s Coloring of the influenced atoms in the three-dimensional structure of IDS was performed for amino acid substitutions including P480R (phenotype: severe), P480L (phenotype: attenuated), D334G (phenotype: severe), and D334N (phenotype: attenuated) as representatives, based on the distance between the wild type and mutant to determine the influence of the amino acid substitutions geographically and semi-quantitatively according to the method previously described .In order to help researchers and clinicians who study MPS II, we built a database including the genotypes, clinical phenotypes, references, and structures of mutant IDSs, according to the method described previously .Fig 1A). Then, to elucidate the relationship between the locations of the amino acid substitutions associated with MPS II and the respective phenotypes, we identified the positions of the residues in the wild type IDS protein structure . The locations of the amino acid residues involved in the substitutions were widely spread over the enzyme molecule.A homology modeling server was used to construct a structural model of the wild type IDS protein. For this calculation, several known structures were used as templates . The results of the homology modeling revealed that IDS consists of alpha/beta folds, and that it contains two antiparallel beta-sheets (each sheet has 4 beta strands) with alpha helixes around them. The active site is located in the loop region near the N-terminal antiparallel beta-strand, and the D45, D46, C84, K135 and D334 residues comprising the putative active site  are indiTable 1. In the severe phenotypic group, the average values  for the influenced atoms in the main chain and the side chain regarding the amino acid substitutions were 106 (± 113) and 124 (± 125), respectively. In particular, 42 of the 67 severe cases (63%) had 50 atoms or more influenced in the main chain. On the other hand, in the attenuated group, the averages (± SD) of the influenced atoms in the main chain and side chain were 63 (± 78) and 71 (± 84), respectively. Notably, regarding the main chain atoms, 39 of the 64 of the attenuated cases (61%) had 49 atoms or less affected. Fig 2 shows the means ± SD and boxplots of the influenced atoms of the main chain  and the side chain  in the severe MPS II group and the attenuated one. Welch’s t-test revealed that there was a significant difference in the numbers of influenced atoms in both the main chain and the side chain (p<0.05) between the severe and attenuated groups. These results indicate that the structural changes caused by the amino acid substitutions responsible for severe MPS II were generally larger than those for attenuated MPS II. As to the influence of amino acid substitutions on the active site, the atoms of the residues comprising the putative active site were affected in 31 of the 67 severe cases (46%) and 17 of the 64 attenuated ones (27%).Then, we constructed structural models of the mutant IDS proteins and calculated the number of atoms influenced by the amino acid substitution for each mutant model. The results are summarized in Table 1. The means ± SD and boxplots of RMSD values for the severe MPS II group and attenuated one are shown in Fig 2C. The average RMSD values (± SD) for the severe and attenuated groups were 0.074 (± 0.050) and 0.056 (± 0.043) Å, respectively. The Welch’s t-test showed that there was a significant difference in RMSD between the severe MPS II group and the attenuated one (p<0.05). These results indicate that structural changes in the severe MPS II group were larger than those in the attenuated one.To clarify the total structural change caused by each amino acid substitution, the RMSD value between the mutant IDS protein and the wild type was calculated, and the results are summarized in Table 1. Fig 2D shows the means ± SD and boxplots of ASA for the severe group and the attenuated one. In the severe MPS II group, the average ASA value (± SD) was 25.2 (± 40.8) Å2. On the other hand, in the attenuated MPS II group, it was 27.9 (± 38.7) Å2. The results of the Welch’s t-test (p> 0.05) showed that there was no significant difference between the two groups.To identify the locations of the residues associated with MPS II mutations in the IDS protein, the ASA values of the residues in the wild type structure were calculated and the results are summarized in Table 1). For seven of those residues , the RMSD value and the number of affected atoms for the severe group were larger than those for the attenuated one. On the other hand, for 3 residues , the RMSD value and the number of affected atoms for the attenuated group were larger than those for the severe one. As to the other 2 residues (P228 and W345), it could not be determined for which phenotype the RMSD value and the number of affected atoms were larger than the other. Then, we examined the structural changes in IDS caused by P480R (phenotype: severe), P480L (phenotype: attenuated), D334G (phenotype: severe), and D334N (phenotype: attenuated) by means of coloring of the atoms affected. P480 is located near the molecular surface, and far from the active site. P480R is thought to cause a large structural change around the substituted residue, although it does not affect the active site, leading to the severe phenotype. The structural change caused by P480L is small and the influenced atoms are limited, leading to the attenuated phenotype . On the other hand, D334 is a residue comprising the active site, and the D334G and D334N substitutions are both thought to directly affect the structure of the active site. The structural change in the former is larger than that in the latter, leading to the difference in phenotype We next examined the effects of different substitutions at the same residue on the structural changes in the molecule and expression of the clinical phenotypes. There are at least 12 residues in the amino acid sequence of IDS at which different substitutions lead to different phenotypes (mps2-database.org) . The database provides readers with information on 530 MPS II mutations, which include 161 missense ones. The database is equipped with several tools. A text search tool is provided for searching the given text in selected fields of the database. Furthermore, using the control table option, users can search for MPS II mutations connected with specific phenotypes. A structural viewer is included in the database, which allows users to display the three-dimensional structures of the molecules using Jmol . Furthermore, users can use many options for visualizing the structures of mutant IDS proteins.We developed a database including the genotypes, clinical phenotypes, references and mutant IDS structures responsible for MPS II .Regarding the locations of residues involved in amino acid substitutions, Kato et al. examined eight cases (phenotypes: 4 severe and 4 attenuated), and reported that the mutations found in the severe phenotype probably undergo direct interactions with the active site residues or break the hydrophobic core region of IDS, whereas residues of the missense mutations found in the attenuated phenotype were located in the peripheral region . But ourIn order to examine structural changes caused by the amino acid substitutions we calculated the numbers of atoms affected and the RMSD values. The results revealed that structural changes in the severe group were generally larger than those in the attenuated one Click here for additional data file.


These nine metals exceed the values of the natural geological background level of Tertiary period sediments and rocks that form part of the Northern Plateau in Spain. Nemerow and Potential Ecological Risk indices were calculated, with the “improved” Nemerow index allowing pollution within the soil superficial horizons to be determined. The data obtained indicated that the majority of the soil (54.61%) showed low to moderate contamination, 22.31% showed moderate contamination and 21.54% of the samples were not contaminated. If we consider the Potential of Ecological Risk Index (RI), the largest percentage of soil samples showed low (70.79%) to moderate (25.38%) ecological risk of potential contamination, where the rest of the soil presented a considerable risk of contamination. The nine trace elements were divided into three principal components: PC1 , PC2 (As and Hg) and PC3 (Cd). All metals accumulated in the soil came from parent rock, agricultural practices and the run-off of residual waters towards rivers and streams caused by industrial development and an increase in population density. Finally, cartography of the spatial distribution of the heavy metal contents in the soil of the Northern Plateau of Spain was generated using Kriging interpolation methods. Furthermore, the total heavy metal contents in three soil orders present in the area, namely Entisols, Inceptisols, and Alfisols, were analyzed. Other soil parameters, such as the organic matter content, pH, clay content and cation exchange capacity, was measured to determine their influence on and correlation with the heavy metal contents.The environmental quality of soil in the central part of the Northern Plateau of Spain has been analyzed by studying the heavy metal content of 166 samples belonging to the horizons A, B and C of 89 soil profiles. The analysis to assess the environmental risk of heavy metals in the soil was carried out by means of the spatial distribution of nine heavy metals and the use of several pollution indices. The results showed that the concentration values of heavy metals ( Toxic heavy metals present in soil, such as Cd, Cu, Pb, Zn, Ni, Cr, and As, potentially affect the environment, because they are durable and non-biodegradable. The accumulation of toxic metals has an impact on natural ecosystems and can present a threat to humans through the food chain, owing to their bioaccumulation in food ,2,3,4. The natural concentrations of trace elements in soil play a key role in controlling the impact caused by humans and in the level of soil quality of an area ,6,7. StuThe assessment of environmental quality, based on the heavy metal contents in soil, involves the use of different pollution indices: the geoaccumulation index, the pollution load index, the potential of ecological risk index, the Nemerow index  and so oOver the last decades, the research on the environmental geochemistry of heavy metals, owing to their toxicity and durability in the environment, has greatly advanced ,30,31. RThe presence of values that exceed the background threshold level of a given geological area is the traditional method used to characterize the degree of soil pollution . High coThe aim of the present work was to: quantify the environmental quality of the soil of the Northern Plateau of Spain by analyzing its heavy metal contents; assess the environmental risk of heavy metals by calculating various pollution indices and by analyzing their spatial and vertical distribution (within deep layers and throughout the entire soil profile); determine the correlation between the heavy metal contents and some soil parameters, such as the organic matter content, pH, clay content and cation exchange capacity; and calculate the average content of heavy metals, according to the type of parent rock and land use.2, which includes the whole area of the province of Valladolid and most of Palencia and Burgos. This area has a Mediterranean climate with cold and rainy winters in addition to hot and dry summers. The average annual rainfall is between 400 and 550 mm, while the average annual temperature is between 11 °C and 12.5 °C. The annual precipitation is less than the amount of potential evapotranspiration, which is between 660 and 730 mm, and occurs mainly between November and February. The Northern Plateau, an area that forms part of the Spanish Central Plateau, is located to the north of the Central System and includes most of the autonomous regions of Castile and Leon. The study area, located within the Northern Plateau, occupies approximately 25,050 kmFrom a geological view point, this area belongs to the great Cenozoic depression of the Duero Basin, caused by the collapse of the Hercynian base and filled up throughout the entire Tertiary period with sediments originating from the continent with a tabular–horizontal arrangement. This basin is surrounded by mountains  37]..37].In each lithological unit, an inventory of the most representative types of soil was conducted, with the profiles described and classified, according to the U.S. soil taxonomy ,39. The (a) Calcareous wastelands: this unit is comprised of the Late Miocene limestones that form a flat surface or a calcareous platform characteristic of wastelands, depending on their specific horizon. The physiographical features show a predominance of little-developed and dense soil (Xerorthents) as well as moderately thick soil .(b) Gypsiferous loam slopes: a unit comprised mainly of soft materials  from the Late Miocene period. The soil comprising these hills and slopes has a clay-like texture, are highly chalky, and exhibit different degrees of erosion. These are related directly to the gradient of the slope, ranging from Haploxerepts to Xerorthents.Tierra de Campos facies). The most characteristic soil on top of this type of lithology has been classified as Haploxerepts.(c) Countryside or undulating plains: a unit shaped by detrital material and comprised of alternating sandstones and silty clays. This is slightly chalky and from the Miocene period  Fluvial terraces: these terraces represent the remains of ancient riverbeds (Pleistocene), tiered to different heights. These run parallel and in the longitudinal direction along the course of the most abundant rivers  and are comprised of generally well-cemented conglomerate deposits of quartzite, quartz and limestone in most of the ancient riverbeds. The lower or more modern riverbeds are comprised of gravel with sandy intercalations. The soil situated above this type of lithology has been classified as Palexeralfs and Haploxeralfs . (e) Flood plains or water meadows of large rivers: these sediments are generally made up of silts, sand and loose gravel. The most characteristic soil of this unit has been classified as Calcixerepts and Xerofluvents.(f) Wind sands: throughout the entire Quaternary period (Pleistocene-Holocene), wind gave rise to various erosional and sedimentation processes, creating loose arkose deposits with round grains. In some cases, these form dunes 15 m in depth, although these do not reach even one meter in other places. The sandy areas are usually alluvial deposits from rivers and sands from the Utrillas facies (Cretaceous), belonging to the Mesozoic period of the Iberian mountain range. This area is covered by white loose sands, forming soil classified as Xeropsamments.The soil sampling sites were chosen, based on the different lithological units. In each site, individual samples were randomly taken for each of the horizons . In each horizon, five were collected and mixed to give homogeneity, obtaining a total of 1 kg of soil. This was subsequently dried at room temperature and then passed through a 2 mm sieve. In each site, individual samples are collected for each of the horizons . In each horizon, five sub-samples are collected and mixed to give homogeneity, obtaining a total sample of 1 kg. The number of samples was 166 in total, which belongs to the soil profiles from the horizons A, B and C. Considering the five sub-samples of each horizons, the total number of collected samples is 830. The physical and chemical properties were determined using the traditional soil analysis methods : organicThe total contents of heavy metals in soil have been analyzed according to the procedure recommended by the European Union ISO standard 11466. Extraction was performed with a mixture of nitric acid and hydrochloric acid in a microwave oven, with determination by ICP-MS model Elan 6000 of Perkin–Elmer. The analysis was carried out by the Chemical Analysis Service of the University of Salamanca through the digestion of the samples in a microwave oven (Millestone mod. Ethos Plus Microwave Lastation), using the standard method, USEPA method 3052. For the calibration of the equipment, standard solutions (panreac) of 1000 mg/L of all the metals analyzed were used, which were calibrated from 10 to 100 ppb. The data of the relative standard deviation (RSD) have all been less than 3% for all elements analyzed.In addition, to check the quality of the analysis, blind duplicates were analyzed. The quality control of the data showing detection limits, accuracy and precision. For the elements: As, Cd, Co, Cu, Cr, Hg, Ni, Pb and Zn, the detection limit are: 0.1, 0.01, 0.1, 0.01, 0.5, 5, 0.1, 0.01, and 0.1 respectively, the accuracy is 2.3%, 0.6%, 1.4%, 3.2%, 7.6%, 1.3%, 1.7%, 1.4% and 2.8% respectively and the precision is 0.5%, 0.2%, 0.4%, 0.7%, 1.9%, 0.3%, 0.4%, 0.5% and 0.8% respectively. Nearly 6% of the samples were analyzed in duplicates internal and external controls. The accuracy error and the precision error were estimated as 2.5% and 0.6% respectively, which denote high confidence in the results.The statistical analysis was carried out using the SPSS v.23.0 software . A descriptive analysis was obtained using the following variables: arithmetic mean, geometric mean, median, range, standard deviation, variable coefficient and kurtosis. In addition, several pollution indices were calculated to determine the level of contamination of heavy metals in the soil. Finally, a multivariate analysis was conducted using the principal components method to identify relationships between the heavy metal concentrations in the soil and to obtain information concerning the possible sources responsible for the presence of the heavy metals . i)Z , with the extensions of spatial analysis tools and geostatistical analysts, calculated the degree of spatial variability of each of the heavy metals and the pollution indices , using standard Kriging to determine interpolation and the subsequent semivariogram analysis . KrigingThe two steps of the process carried out in this work are as follows: to create the variograms and the covariance functions to calculate the values dependent on statistics  that are dependent on the model of autocorrection (adequacy of fit) and to determine unknown values (prediction). In this work, the Kriging method applied was standard, which presumes that the distance or the direction between sampling sites reflect a spatial correlation that can be used to explain variations within the surface area. The semivariogram model uses the spherical mathematical model, which adjusts the mathematical function to 12 sitepoints in a search radius variable .The mean values of the heavy metals obtained as a result of the statistical analysis of the soil of the Northern Plateau of Spain can be seen in The mean values of As, Cd, Ni, Cr, Pb, Cu, Hg, Co and Zn in the soil were 1.18, 1.19, 1.40, 1.49, 1.50, 1.54, 1.55 and 1.67 times higher, respectively, than their natural geological background levels. All these data show that there is an evident tendency towards the accumulation of heavy metals in the soil of the region studied.The variation coefficient of Pb and Hg, which were 0.80 and 0.76 respectively, were the highest, implying that these two metals had the greater variability throughout the area studied compared to the other metals also present in the soil: As, Cd, Co, Cu, Cr, Ni, Pb and Zn , which also showed high values (>41%) dispersed along the sampled areas.iP) quantifies the pollution of one individual metal, iP = iC/iB, where “iC” is the concentration of the measured contaminant and “iB” is the geological background level, which allows the levels of the different metals to be determined.The Pollution factor (NI) assesses soil quality, according to the degree of pollution of various metals and taking into account the pollution factor. This was defined by the following equation (Equation (2)):maxPi” is the maximum value and “avePi” is the mean value of the pollution factors of all the metals , 59.15% have moderate pollution (1 ≤ Pi < 3), 5.65% have high pollution (3 ≤ Pi < 6) and 4.62% have very high pollution (Pi > 6). This data show that a large percentage of the soil was polluted to a low to moderate degree and that only a small amount of soil was highly polluted. According to the results of this pollution factor, four categories were established: 34% of the samples studied have low pollution (NI < 2) represented 46.15% of the samples analyzed, the soil “moderately contaminated”  represented 36.92% and the “highly contaminated” soil  represented 14.62%. The slightly contaminated soil  were less represented and only made up 0.77% of the samples. In comparison, non-contaminated or clean soil  made up 1.54% of the samples analyzed.The levels of pollution according to the Nemerow index in the study area show that the majority of the soil presented low to moderate contamination, while only a small percentage was non-contaminated or slightly contaminated. The soil considered as “contaminated” , from non-contaminated to moderately contaminated , moderately contaminated , from moderately contaminated to highly contaminated , highly contaminated , from highly contaminated to extremely contaminated  and extremely contaminated .The geo-accumulation index (Igeo) is calculated using the following equation (Equation (3)):MNI) showed the overall degree of pollution caused by the simultaneous presence of the nine heavy metals (The geo-accumulation indices (Igeo) of the heavy metals studied allowed the pollution index, with only one factor to be analyzed in order to assess the presence of each specific metal and the corresponding level of contamination in the area studied. Furthermore, the “improved”, multifactorial Nemerow index . The majority of the soil contents were situated within Classes 0 (56.23% of samples), 1 (36.07%), 2 (7.79%) and 3 (2.34%) (unpolluted to moderately polluted). MNI) substitutes the contamination factor (iP = iC/iB) for the equation Igeo = log2 (iC/1.5 iB), in which the MNI is calculated using the following equation (Equation (4)):MNI), the soil was shown to be moderately to heavily contaminated. Specifically, 21.54% of the soil was uncontaminated , 54.61% was between uncontaminated to moderately contaminated , 22.31% was moderately contaminated  and 1.54% was moderately to heavily contaminated . Furthermore, there are no samples belonging to Class 4, which is heavily contaminated (3 ≤ MNI < 4); Class 5, which is heavily to extremely contaminated (4 ≤ MNI < 5); and Class 6, which is extremely contaminated (MNI > 5).The “improved” Nemerow index (Er) assesses the toxicity of some trace elements in sediments [The Potential of Ecological Risk Index  for each metal, the following equation was used (Equation (5)):Tr” is the toxicity coefficient of each metal, which standard values are: Hg = 40, Cd = 30, As = 10, Co = 5, Cu = 5, Ni = 5, Pb = 5, Cr = 2 and Zn = 1. To calculate the Potential of Ecological Risk index ):RI) reflects the general situation of the contamination caused by the simultaneous presence of the nine heavy metals , moderate ecological risk 150 ≤ RI < 300), considerable ecological risk (300 ≤ RI < 600) and very high ecological risk (RI > 600). It was observed in the area studied that a large percentage of the soil samples (96.92%) were within low to moderate ecological risk of potential contamination, with only a small proportion (3.08%) posing a considerable risk of potential contamination.The categories established for the RI index for classifying risk are: low ecological risk of potential contamination . The geographical location of the samples with the highest Cd values showed that the second component basically collected information of samples where the concentration of this element was caused by agricultural practices    right.Pb = 80%). This indicated that the distribution of Pb was diverse and fluctuating, with its concentration at each site potentially being conditioned by multiple factors, including human activities [Lead (Pb) contributed very little to the three principal components of this multivariate solution. It was known that the mean value of this element in the study area exceeded the natural geological background level and that its coefficient of variation was the highest out of all the metals studied , showed that the relationship between the metal concentrations were sometimes small but not negligible. The Pearson correlation coefficients for the heavy metal concentrations in the soil samples  showed aCu, Cr, Ni and Zn were the most related elements with direct connections, which indicated that these metals were generally present in the samples at the same time and in equivalent or proportional quantities, suggesting that the origin of these elements was mainly lithological. However, there was an inverse relationship between the concentrations of Cd and As with the rest of the metals. The metals, Hg and Cd, had a sporadic inverse relationship with Co. These relationships could serve to identify artificial sources caused by different human activities. The correlation analysis between the total contents of heavy metals and some soil properties has shown  that theThe geostatistical method of spatial interpolation (standard Kriging) allowed for the spatial distribution of the values of each metal in non-sampled sites  to be prBy applying the geostatistical analysis extension, we analyzed the resulting charge histogram of all the sample data and implemented the logarithmic transformation. This allowed the frequency histogram to be fitted to a normal distribution and equalized the values of the mean and median. Standard Kriging was applied with a prediction surface output and a logarithmic transformation. This process was further carried out by applying an exponential-type Kernel function and obtaining a spherical semivariogram A with reNM  B, it canThe evaluation of the environmental risk of heavy metals in the soil has been carried out through several pollution indices, a principal components analysis and the spatial distribution of nine heavy metals.Pi), Geoaccumulation Index (Igeo), Nemerow “Improved” Index (IMN) and Individual Ecological Risk (Er) and Potential Indices (IR) have been calculated.The indexes of Nemerow (IN), Pollution Factor (MNI), the soil was shown to be moderately to heavily contaminated. A large difference was observed when calculating the percentage and degree of contamination of the soil using each of the different contamination indices. In the soil of the Northern Plateau of Spain, the MNI was a better representation of the actual degree of contamination present.After taking the Nemerow index into account, the soil within the study area ranged from being contaminated to highly contaminated. However, using the “improved” Nemerow index  have a low to moderate ecological risk of potential contamination, while the minority (3.08%) of the soil has a considerable risk of contamination.Therefore, both the “improved” Nemerow index and the Potential Ecological Hazard Index are the best in informing us of the degree of contamination in the surface horizons of the soil of the Northern Plateau of Spain.p < 0.01), providing evidence for one shared origin of these metals. The lack of significant linear correlation between Cd and other metals suggests that sources of Cd must be very different from those of other metals. These data suggest that concentrations of heavy metals could be affected by more than one source of pollution, including the following: from the parent rock itself, from agricultural activities and from the discharge of wastewater into rivers and streams. It is hypothesized that the contamination is caused by industrial development and increasing population density ; CP2 (As and Hg) and CP3 (Cd). Pb has a similar and scarce contribution across all the three main components. Pearson correlation coefficients and their significance levels indicate that most concentrations of heavy metals are positively correlated with each other (with the exception of Cd correlations). Furthermore, these were all statistically significant correlations, which implies that the contents of these heavy metals have been supplied from very similar sources of contamination. The correlation coefficients of the metals belonging to the CP1  indicate a strong and significant linear correlation  were found to be significantly correlated with Co, Cu, Cr, Ni, Pb and Zn concentrations. This confirms the high affinity of certain elements with the minerals of the soil clay. However, soil pH is significantly correlated only with Pb concentration. It was found that the concentration of the heavy metals increases in the more clay-like horizons of the soil (Bt horizons of the Alfisols and Bw of the Inceptisols), which can easily be explained if we take into account that the adsorption capacity of these elements in soil depends on a number of properties, such as clay content, organic matter and cation exchange capacity.A mapping, of the spatial distributions of heavy metal contents in the soil of the Northern Plateau (Spain) has been carried out using by interpolation methods (Kriging).The distribution of the heavy metals  was very similar and all had high concentrations in the soil. These heavy metals were found in the north-western section of the study area in soil that had developed on top of the sediments of the “Tierra de Campos” facies. High values for these elements were also observed in the soil overlaying Miocene limestones as well as on top of the terraces, alluvial deposits of the rivers and streams that run through the area. The concentrations of these metals were influenced by the contents of the parent rock. Furthermore, the concentrations of Cu and Zn could have been influenced by agricultural practices . The highest Pb content was found within the surroundings of Valladolid, the most populated and industrial city , in soilNM) and the potential ecological risk index (RI). Both reflect the general situation of the contamination caused by the simultaneous presence of the nine heavy metals. This was useful for evaluating the possible sources of the heavy metals in the area studied and for identifying the soil that contained the highest concentrations of the metals. The overall analysis of the soil contamination in the study area was carried out using two contamination indices: the improved Nemerow index . In addition, the correlations are statistically significant, which implies that the contents of these metals have originated from similar sources of pollution and could be affected by more than one source of contamination.Taking into account the values obtained from heavy metals, analysis of main components and their spatial distribution, it can be concluded that a determinant of concentrations of most metals in the soil of the Northern Plateau of Spain is the nature of the mother rock. Some metals, such as Cu, Zn and As, have also increased their content in soil due to certain agricultural activities . Hg is related to soil that has developed on alluvial deposits and irrigated soil. The soil that has developed on limestones and calcareous sediments has a high Cd content and the greater concentration  of Cd in the region occurs in the vicinity of an electric transformer of an urban nucleus. The highest concentration of Pb occurs in the vicinity of Valladolid due to the gases from the vehicles, industrial sources as well as the discharge of waste water to rivers and streams. In accordance with the improved Nemerow index, most of the soil of the Northern Plateau of Spain are considered to be between “between non-contaminated to moderately contaminated”. According to the Potential Ecological Risk Index, the soil presents a general level of risk that varies from “low to moderate”. The results of this study demonstrate that agricultural production can continue, but there should be some improvement measures to protect the security of agricultural products. This might include a reduction in the amount of fertilizers and pesticides used as well as the application of treatments to the soil in some places. In addition, the results obtained in this research should be useful for establishing future land planning guidelines or for providing recommendations for land use within this region.


A thermal stress range analysis of tungsten-rhenium thin film thermocouples based on ceramic substrates is presented to analyze the falling off and breakage problems caused by the mismatch of the thermal stresses in thin film thermocouples (TFTCs) and substrate, and nano-indentation experiments are done to measure and calculate the film stress to compare with the simulation results. Optimal design and fabrication of tungsten-rhenium TFTCs based on ceramic substrates is reported. Static high temperature tests are carried out, which show the optimization design can effectively reduce the damage caused by the thermal stress mismatch. The temperature parameters of aero-engines are a main influencing factors of the performance and safety of aeroplanes in the aero-engine development process. In recent years, the working temperature of hot components of new aero-engines has grown to achieve a higher thrust weight ratio, for example, the temperature before the turbine of a F119 is up to 1950 K. To reliably prevent over-temperature damage, controlling the temperature in the combustors and turbine blades of aero-engines is therefore an important requirement. Although the traditional test methods can be used in testing these high temperatures, this is still not suited for the harsh environment in aero-engines. Sapphire fiber temperature sensors are hard to apply in online monitoring. Infrared radiation devices are complex and their precision is not enough for use in online measurement of hot components in harsh environments such as aero-engines. Furthermore, the armored thermocouple insulation layer decreases, easily leading to leakage currents, resulting in shunting errors and drift control problems . The thiAt present, the material system of film thermocouples has been diversified with the increase of the working temperature. Tungsten-rhenium alloy has a high melting point of 2700 K and appropriate thermocouple characteristics, which can be used in TFTCs for detecting high temperatures. We have presented a new tungsten-rhenium TFTC structure based on MEMS technology . HoweverTFTCs are usually made by two kinds of material, which are connected into a closed-loop. When the hot terminal is affected by temperature, and once there exists a temperature gradient field between the hot and cold terminals, the voltage could be measured from the cold terminal. The schematic diagram of these thermocouples is shown in As shown in 1, d2 are the dimension parameters. L represents the length the film; d1 means the thickness of the film, and d2 means the thickness of the substrate. In the thermal stress finite element analysis (FEA), the isotropic, thermoplastic and orthotropic behavior of the material was considered in the tungsten-rhenium film combination. The simulations of thermal stresses were performed using finite element analysis. The material parameters in the model are listed in Considering the substrate is a ceramic material which has a great strength, the thermal stress is not the main factor in the failure of the substrate. The stress finite element model of a TFTC sensor is set up to analyze the thermal stress of the tungsten-rhenium films on the substrate . Due to An analytical model, which shows the average thermal stress, is also set up for contrast. It’s in conjunction with Stoney’s equation for tension in metallic films, which would result in the following equation for thermal stress in thin film as :(1)σth=EThe definitions of the symbols in Equation (1) are given in 1) is 1 μm, the thickness of the substrate (d2) is 100 μm, the length of the film and substrate is 200 μm. The physical parameters are chosen from The relationship between the average thermal stress generated in TFTCs deposited on silicon carbide ceramic substrates and temperature is shown in Thermal stress variation with the increasing thickness of W-3Re film is shown in 1) ranges and d2 = 100 μm. In 2) ranges and d1 = 3 μm. It is observed that thermal stress increases with increased temperature. The reason is the coefficient of thermal expansion mismatch between film and substrate. The thickness of W-3Re film also influences the thermal stress of W-3Re film deposited on a substance, and with the increase of the thickness of W-3Re film, the thermal stress decreases [In ecreases . This isxz) of W-3Re with the distance through thickness at different position, we choose silicon carbide ceramic as the substrate and W-3Re as the film, d1 = 1 μm, d2 = 100 μm, the lower surface of substrate as base level, and lateral boundary of the model as the datum edge. Edge 1, Edge 2, Edge 3 and Edge 4 represent the positions which have a distance of 1 times, 5 times, 10 times, 15 times d1 from the datum edge. It is observed that the maximum tensile shear stress is at the interface in the film edge in the case of substrate and the maximum compressive shear stress is at the interface in the film deposited on substrate in To analyze the distribution of shear stress, and the chose dm stress . The resConsidering a film under high temperature thermal stress mismatch will cause damage, an orthogonal range analysis is done to find out the main factors influencing the thermal stress of the W-3Re film of TFTCs, so as to determine the best factor level for the thermal combination effect. As the substrate material has been selected, W-3Re film thermal stress is mainly affected by the thickness of the ceramic substrate, the expansion coefficient of tungsten-rhenium film thickness, and the temperature. According to the three factors and three levels of orthogonal experimental requirements, each factor of the three different levels is determined in We select film stress as the index, the results are shown in 1, K2, K3 show the sum of film stress at the levels 1, 2, 3 respectively, k1, k2, k3 show the average values of film stress at the level of 1, 2, 3 respectively, R is the range value. The thermal stress data from KBased on range analysis, we choose the dimension parameter used in experiment 1 for the optimization scheme of TFTCs to confirm the results of the simulation analysis. Suitable tungsten-rhenium TFTC structures were prepared and tested.We choose W-3Re film for the composition and morphology of the films. The scanning electron microscope  results are shown in The X-ray diffraction , Beijing, China) and X-ray photoelectron spectroscopy , Shanghai, China) results are shown in The TFTC sensor materials used include tungsten-rhenium, silicon carbide ceramics, and mixed high temperature binder. Ceramic substrate is made by powder sintering. It’s cut into the proper size and polished to make films sputter on the surface successfully. The substrate is ultrasonically cleaned with deionized water, acetone, etc. TFTCs are fabricated by a micromachining process using sputter technology and UV lithography. The TFTCs are patterned with stenciled shadow masks. The TFTCs (tungsten-3% rhenium versus tungsten-25% rhenium) are deposited directly onto the substrate surface. Some related process parameters are listed in A diagram of the process is shown in Then TFTCs sensors are heat treated in a protective atmosphere. Finally, the cold terminal films are connected with wires using a mixed high temperature binder at 120 °C.A static thermal environment was used for testing the performance of TFTCs. A muffle furnace  with a maximum high temperature of 1800 K is used to provide the test environment shown in The experiment result is shown in TFTCs without dimensional parameter optimization were tested for comparison. These can only bear the temperature for one minute before the film rupture even when the material is the same. The TFTCs without optimization fall off and break. The substrate thickness of TFTCs without optimization is 3 mm, the W-3Re films thickness 50 μm, the length of the film and substrate is 8 cm. Two types of W-3Re TFTCs are prepared and tested when a similar temperature difference is applied, as shown in Range analysis of thermal stress of tungsten-rhenium thin film thermocouples based on ceramic substrates is presented to explain the falling off and breaking problem caused by the mismatch of the thermal stress in TFTCs and substrates. FEA and numerical analysis is used to calculate the thermal stress, and nano-indentation experiments are done to measure and calculate the film stress to compare with the simulation results. The relationship between substrate materials and dimensional parameters is analyzed and the optimal design of tungsten-rhenium TFTCs is reported. The range analysis of thermal stress in W-3Re films shows the temperature has a greater influence on the thermal stress than the thickness of the film, and the influence of film thickness on thermal stress is relatively the lowest.Static high temperature tests are carried out after the TFTCs are fabricated. The maximum thermoelectric voltage of TFTCs subjected to a temperature difference of 600 °C was 8.46 mV on SiC substrates. It is observed that the TFTCs without optimization fall off and break after exposure to a constant high temperature of 600 °C due to the coefficient of thermal expansion mismatch, and TFTCs with optimization could bear a temperature of 600 °C for an hour. The result shows the optimization design based on the thermal stress range analysis can effectively reduce the damage caused by the mismatch of the thermal stress in rhenium thin film thermocouples based on ceramic substrates in a certain temperature range.


The conventional lingual arch is a nonfunctional fixed space maintainer used in the mandibular arch to maintain arch length by the prevention of mesial movement of the permanent first molars. This study highlights a functional lingual arch with a hinge-type lockable dentulous component that incorporates molar tubes, with various advantages over the conventional lingual arch. Chalakkal P, Ferreira AN, Da Costa GC, Aras MA. Functional Lingual Arch with Hinge-type Lockable Dentulous Component. Int J Clin Pediatr Dent 2017;10(3):302-308. Upon examination, the lower arch contained the following teeth: 36, 35, 34, 73, 32, 31, 41, 42, 83, and 46 . The uppPlaster blockout of the undercuts and buccal tubes was done . AcrylizThe tubes on the buccal surface were incorporated in order to pass the locking wire (0.64 mm) that formed the locking component of the appliance  and 20. 22 and can measure up to 4.3 mm.23 As much as 4.8 mm of space becomes available after the permanent canines and premolars replace their primary successors.24 Normally, the first molars move mesially into the leeway space, decreasing the arch length.23 This space can be preserved by maintaining the arch length with passive appliances, such as the lingual arch. In the current case, although extraction of 84 and 85 was carried out a year ago, there was no resultant loss in arch length when the distances between permanent molars and primary canines were measured on both the mandibular quadrants and compared. Moreover, space analysis had shown the presence of sufficient space for the eruption of 44 and 45. There was no loss in arch length probably because the extraction of 84 and 85 were carried out during the second transitional period, rather than the first or intertransitional periods.Leeway space represents the difference between the sum of the mesiodistal diameter of the primary canine and molars and the sum of the mesiodistal diameter of the permanent canine and premolars13 Although the extraction of primary molars had been carried out a year ago, narrowing of the corresponding region of the arch was observable.Early loss of primary molar teeth can eventually cause narrowing in the dental arch.7 Such was the situation in the patient as per the OPG with regard to 44 and 45. The thickness of wire used for the construction of the LHLD was 0.9 mm. Lingual arches made with 0.9 mm stainless steel wire are superior in terms of arch length preservation.18 Owais et al18 showed that 1.25 mm wire increased the stiffness, resulting in increased forces on the lower incisors and first molars, as compared with 0.9 mm wire. This resulted in greater proclination of the incisors and loss of the Leeway space. Additionally, increased wire stiffness resulted in higher cementation failure and wire/band breakage.Space maintenance is indicated when the succeeding tooth has < 75% of root formation, or when there is >1 mm of alveolar bone above it.27 However, the LHLD does not have any of the above disadvantages. Never before in dental literature has a similar appliance been fabricated. It has the following advantages:A conventional lingual arch has the following drawbacks: (1) Risk of extrusion of antagonist teeth into the lower edentulous space and (2) nonfunctional . The hinge-type design provides easy visualization of the ridge by opening the dentulous component around its hinge axis without having to deband the lingual arch, after the locking component is opened. Periodic inspection of the ridge is required to check for any mucosal alterations and to check for eruption of the premolars. The locking component can be opened by cutting and removing the wire that passes through the molar tubes on the buccal aspect. After inspection, a new wire can be passed through the tubes and turned into a loop mesially and distally, in order to lock the dentulous component. The appliance helps in mastication since it is functional. The underside of the dentulous component can be cleaned upon opening the dentulous component. There is prevention of overeruption of antagonist teeth28It also satisfies all the requirements of an ideal space maintainer, such as: (1) preservation of space; (2) allows for eruption of adjacent, succedaneous, and abutment teeth; (3) restoration of masticatory function; (4) prevention of over eruption of antagonist teeth; (5) compatibility with soft tissues; (6) effective hindrance of torquing forces on abutment teeth; (7) economy of construction and resistance to distortion; (8) allowance for adjustment or minor repair; and (9) universal application.However, since it is a fixed appliance with an acrylic component, maintenance of oral hygiene would often be difficult. This remains the disadvantage of the appliance.The LHLD has various advantages over the conventional lingual arch for being a functional space maintainer for use in the lower arch.


Each component of the technique system was quantitatively validated and visually compared to images, and the sensitivity of the virtual clipping algorithms was analyzed. This technique is inexpensive and accurate and provides high throughput for the measurement, reconstruction, and trait extraction of rice canopy architectures. The technique provides a more practical method of data collection to serve functional–structural plant models of rice and for the optimization of rice canopy types. Moreover, the technique can be easily adapted for other cereal crops such as wheat, which has numerous stems and leaves sheltering each other.This study developed a technique system for the measurement, reconstruction, and trait extraction of rice canopy architectures, which have challenged functional–structural plant modeling for decades and have become the foundation of the design of ideo-plant architectures. The system uses the location-separation-measurement method (LSMM) for the collection of data on the canopy architecture and the analytic geometry method for the reconstruction and visualization of the three-dimensional (3D) digital architecture of the rice plant. It also uses the virtual clipping method for extracting the key traits of the canopy architecture such as the leaf area, inclination, and azimuth distribution in spatial coordinates. To establish the technique system, we developed (i) simple tools to measure the spatial position of the stem axis and azimuth of the leaf midrib and to capture images of tillers and leaves; (ii) computer software programs for extracting data on stem diameter, leaf nodes, and leaf midrib curves from the tiller images and data on leaf length, width, and shape from the leaf images; (iii) a database of digital architectures that stores the measured data and facilitates the reconstruction of the 3D visual architecture and the extraction of architectural traits; and (iv) computation algorithms for virtual clipping to stratify the rice canopy, to extend the stratified surface from the horizontal plane to a general curved surface , and to implement  A plant architecture is defined by a set of features describing the shape, size, location, and orientation of the three-dimensional 3D) organization of the plant body above ground . This arD organizOryza sativa L.) is one of the dominant grain crops in most developing countries and is the staple food of more than half the world’s population  average filter.3. For a given leaf, its dataset of real coordinates (L) for defining the leaf shape was calculated by 4. The leaf width along the leaf vein was derived using x,y) on the leaf in ∈L, Lw(Ll) is the leaf width at this point, where the horizontal distance to the leaf node is Ll and the Lmw is the maximum leaf width. For a given leaf L, the leaf length is the maximum Ll, and the leaf width changes from leaf node to leaf tip, defined as 5. The leaf shape curve function as a 6th-degreepolynomial was derived from the data of Ll and LW (Ll) /2 ( (Ll) /2 ,a, b, c, d, e and f are the function parameters and g is the residual of the function.The leaf venation profile data were extracted from the tiller image through the following analysis .4. The dataset of the real coordinates of the stem for defining the stem shape (S) and the dataset of the real coordinates of the leaves for defining the leaf curve (Lc) were calculated by 5. To determine the length and radius of the stem  as well as the position of the leaf node and the point set of the midrib of a leaf , the coordinates were rotated to parallel the stem approximately along the vertical axis and were also shifted at the center of the stem bottom to the coordinates . For a given stem S, its length and radius at different positions from bottom to top were derived using Eqs Lc, its node position as the attached point of the leaf on the stem and the point dataset of the midrib of the leaf were derived using Eqs Sr(z) is the stem radius at a distance z from the stem bottom.6. The leaf midrib curve was described by the parameters xlm(l) and ylm(l)  to the leaf node.d ylm(l) , which f(l) LMO,  in referIn this study, the digital plant architecture was defined using structural data with spatial position reference, shape, and size for different objects, from hills in the field to the stem and leaves attached to the plant, and using operations for the reconstruction of the 3D virtual plant architecture and trait extraction. The structural data are defined as described in Structural data were collected through experimental recording, measurement, and image analysis. In this study, the structural data of the digital geometrical structure were obtained in a 3D Cartesian Coordination System that corresponds to the cylindrical coordinate system, with the orientation along the horizontal plane, the longitudinal axis at the center of the stems, and the polar axis given by the marked azimuth of the hill.rs, ps).The planting space is the row and plant space represented as .The hill position in the field is represented by the row and column numbers in the sampling block as  and  in rj, aj, hj) is a point of the stem measured by the Clindrical Coordinatograph method described in The stem length is denoted by SR(zi), i = 1…N, and zj-1<zj, j = 2…N obtained through θ measured by the Clindrical Coordinatograph method. The leaf node is denoted by  ∈LN is defined in zt is defined in The stem radius is denoted by yln,zln) , where ) in Eqs li, xlm,(li) ylm(li) zlm(li)), li-1<li, i = 1…N, as li, xlm,(li) ylm(li)) is calculated from SL is the stem length as in The leaf width is denoted by  yls(li) zls(li)), li-1<li, i = 1…N,  yls(li) zls(li)) are the spatial 3D coordinates of points on the leaf on two edges - xlm,(l1), ylm(lm)- ylm(l1) zlm(lm)- zlm(l1)) × - xlm,(lm), ylm(lN)- ylm(lm) zlm(lN)- zlm(lm)), P =  is the vector perpendicular to the plane of leaf venation, norm(P) is the modulus function, the two terms on the two sides of the multiplication sign (×) are the two vectors defining a surface, and P is the productive vector defined by the vector components p1, p2 and p3.The leaf shape is denoted by <FA for any ∈R3, and 3R is the 3D real space.The virtual blade method  can be di is the series number of leaves and Ω = ⋃Ωi is the integration of all leaf-cutsections of all leaves. Thus, traits between sections A and B can be computed in Ω.If a leaf surface can be described by sago cycas, a set of cylindrical surfaces are chosen as virtual blade sections to investigate the leaf areadensity function on the distance from the central vertical axis of a hill (i.e. hill axis). For the rice canopy, where the leaf azimuth is supposed to be homogeneous, the cylindrical surface virtual blade can also be used for the density function on the distance from the hill axis.Various virtual blade sections can be chosen for a specific objective. In the case of horizontally homogeneous canopies, if a set of horizontal sections can be chosen as virtual blade sections to investigate the density function along the vertical axis, the virtual blade technology is equivalent to the virtual stratified clipping method. In the case of concentric circle homogeneous canopies, such as However, it is difficult to determine the trait distribution using the virtual blade method directly because we have to solve many equations for the intersections of surfaces. To simplify the virtual blade method, we proposed the use of algorithms for the virtual blade method  to compute an approximately trait distribution. Based on the 3D digital geometrical structure, the virtual blade algorithm for extracting leaf trait distributions is described by the following steps:Reconstruct the 3D digital geometrical structure;Fk = 0, k = 1,2…,m and a set of interspace {|FA>0,FB<0,Fk = 0}, k = 1,2⋯m-1;Define a set of parallel blade sections, Divide the leaves into fragments and compute the traits of each fragment;Fk = 0 and Fk+1 = 0. The details of the algorithms are presented in Summarize the traits of each fragment in intervals between parallel blade sections xoy, xoz, and yoz planes can often be chosen as virtual blades. Sequentially, the space of the canopy is split into m×n or m×n×l sub-spaces named voxels. The process for generating a virtual blade is described in If the difference in architecture traits at different positions in a flat space or 3D space is investigated, virtual blade algorithms can be adopted for 2D or 3D distributions of architecture traits via the extension of a single-group blade to a multi-group blade. Three types of planes parallel to the nsD (cm) (see floor(x) rounds x to the nearest integer less than or equal to x.The leaf area density along the z-axis was investigated using the virtual blade method . In this(cm) see ; the lea(cm) see . The ordli+1 and li (cm) are the curve distances on the leaf vein from the upper and lower ends of the ith fragment to the leaf node, and Lw(li+1) and Lw(li) are the leaf width at the upper and lower sides of the ith fragment.The area of a fragment as an experimental trait was also calculated by n was determined by The leaf area in interval Dns1= 10 cm, Dns2= 5 cm, and Dvn3= 1 cm, and the leaves were divided into fnum fragments . The leaf area density along the z-axis is presented in The distances between two neighboring sections see  were chofnum = 100, the leaf area density along the z-axis was different among Dns1= 10 cm, Dns2= 5 cm, and Dvn3= 1 cm at z-axis intervals from 26 to 38 cm and from 47 to 64 cm . The area density distribution as a function of the distance to the hill axis is shown in The distance between two neighboring cylinder surfaces was tested under three assumptions: xyz plane was divided into voxels with a distance along the x-axis (Dx), along the y-axis (Dy), and along the z-axis (Dz) and with each leaf divided into fnum fragments along the leaf midrib. Each fragment was represented by four points:  yls1(li) zls1(li));  yls2(li) zls2(li));  yls1(li+1) zls1(li+1)) and  yls2(li+1) zls2(li+1)).The leaf area density on the XYZ (or XOY) plane was investigated using the algorithm for virtual point vertical quadrate sampling , where ZEach first order of leaf fragment was furtherly divided into four secondary smaller fragments by the midrib and the two midlines of the midrib and edge .farea = (li+1-li)(Lw(li+1)+Lw(li))/8. The voxels containing the fragments were determined by nx,ny,nz) was calculated by xoy plane was calculated using In this case, the virtual blade method algorithm was used, with the leaf area as the trait. The area of the fragment was calculated as dn equivalent portions, and each leaf was divided into a number of fragments along the leaf midrib (fnum)  ylm(li) zlm(li)) is the leaf midrib.The leaf azimuth distribution was investigated using the virtual blade method algorithm . The 0 tb (fnum) . The aren was calculated using The interval in which the smaller fragments were located was calculated using farea) was calculated using n were calculated using The leaf inclination distribution along the z-axis was investigated using the virtual blade method algorithm , similarfarea were calculated using inclinfrag was calculated using The leaf inclination distribution as a function of the distance to the axis of a hill was investigated using the virtual clipping method , similarθleaf = finclin, φleaf = fazimuth, θsun is the solar altitude angles, and φsun is the sun azimuth angle.The light distribution along the z-axis was investigated using the virtual blade method algorithm , similarn was calculated using n was calculated using The total projection area on the plane perpendicular to the sun by the fragments in interval To test the accuracy of the measurement of the stem spatial position, the actual and simulated images of the plant stem were compared for Sample S6. The spatial position and radius at five points on the surface of each stem were measured with the CC tool. The five points on the axis of each stem were calculated with the measured five coordinates and radius. A total of 40 leaves (5 groups from Sample S7) were used to validate the performance of the LIAE and the leaf image analysis. The data on length, maximum width, and area of each leaf generated through the image acquisition equipment and leaf image analysis were statistically compared with those measured using a ruler and the LI-COR LI-3100C leaf area meter . The datTo validate the performance of the TIAE and the tiller image analysis, data on the base and dropping angles of 33 leaf blades (7 tillers from sample S7) were extracted through the TIAE and tiller image analysis and also measured using a digital angle ruler. The measured base and dropping angles were very well represented by the extracted angles , with thSamples S4 and S5 (two hills of the rice plant with trim-moldings) were used to assess the reconstruction of the rice plant canopy. Pictures of the plant hills from the side and top angles/views were taken before the measurements . These pTo assess the technology system developed in this study, the light intensity (photosynthetic active radiation) and leaf area index were measured by a Sunscan SS1-UM-2.0 (Delta-T Devices Limited) at canopy layers in a interval of 20 cm from bottom to top, with three replications every 15 cm in each layer. The measurements were conducted at 13:30 on 10-March-2015.2 ≈ 1.0) and a slope of the linear regression between measured and calculated values were approximately to 1.The measured and calculated light intensity fractions to the radiation at the top of the canopy  has samlThis study focused on the measurement of rice plant architectures, the reconstruction and visualization of digital architectures, and trait extraction from the digital architectures. A technique system, consisting of the location-separation-measurement method (LSMM) for measurements, developing equipment for data acquisition and image capturing and software programs for image analysis, defining and reconstructing the data structure of the digital architecture, visualizing the 3D plant architecture, and using the virtual clipping method for trait extraction based on the digital architecture, was developed and validated.This technique system is a low-cost and accurate system because it does not involve expensive devices, and the results demonstrated that the 3D visual architectures reconstructed using the technique system of this study were comparable to actual plant architectures, and the calculated leaf areas in the canopy layers and light interception at different depths of the canopy based on the digital plant architecture were in good agreement with the measured values. Moreover, the reconstruction of the 3D plant architecture based on directly obtained data is not the same as the L-system based on a statistical parameter .This technique system achieves a high throughput. It can collect and extract plentiful information to satisfy plant phenotypic research and plant architecture research. In practical agricultural investigations, three people, working 10 hours, can measure 40–50 hills per day using this technique system. The system is more efficient than the digitizer reported by Zheng  because This study provided other highlights. For example, the data structure of the digital architecture should benefit the repeated use of data, the virtual clipping method should also be useful for the extraction of new indices of plant architectures, and the LSMM represents a feasible procedure for measuring sheltered plant architectures. However, this technique system suffers from certain defects. For example, the system has to operate indoors, the system cannot be operated in the field, and the measurement is destructive.S1 FileThe detail information about the fields’ site, variety.(DOCX)Click here for additional data file.S2 FileThe details of apparatus  and the operation; Algorithm of the reconstruction of the 3D visual geometrical structure of the rice canopy architecture in the field; Data structure of digital plant architecture; Algorithm of the reconstruction of the 3D visual geometrical structure of the rice canopy architecture in the field; Algorithm for trait extraction of canopy architecture using the virtual blade method; And processes involved in the virtual blade method for multi-dimension distributions of architecture traits(DOCX)Click here for additional data file.S1 FigPresentation of the four steps involved in the leaf image process: (a) original image, (b) binary image, (c) leaf image after pixel transformation, and (d) leaf shape curve after polynomial fitting.(TIF)Click here for additional data file.S2 FigPresentation of the four steps involved in the leaf image process: (a) original image, (b)binary image after gray processing, (c)tiller image after stem extraction, (d)tiller image after coordinate rotation, and (e)tiller image after equation fitting.(TIF)Click here for additional data file.S3 Fig(a) virtual blade method with horizontal surfaces, (b) virtual blade method with cylindrical surfaces, 1: virtual blade sections, 2: the distance between two neighboring adjacent surfaces.(TIF)Click here for additional data file.S1 TableAbbreviations are listed with their full words and meaning.(DOCX)Click here for additional data file.S1 DataThere four type file in the zip file, SystemData is parameters of paratus, SSP_LCAA correspond to the special position of stem, leafvein correspond to data of leaf midrib curves, leafshape correspond to the data of leaf shape. 0: correspond to Sample S4, 1: correspond to Sample S5.(ZIP)Click here for additional data file.S2 DataThere four type file in the zip file, SystemData is parameters of paratus, SSP_LCAA correspond to the special position of stem, leafvein correspond to data of leaf midrib curves, leafshape correspond to the data of leaf shape. 101: correspond to neighbor 8 hills of Sample S1 (NSICRc222), 1: correspond to neighbor 8 hills of Sample S2 (NSICRc124H).(ZIP)Click here for additional data file.


This study examined the implementation quality of the Tier 1 Program (Secondary 1 Curriculum) delivered in the second year of the Full Implementation Phase of the Project P.A.T.H.S. . Under the “Co-Walker Scheme”, systematic observation of curriculum units was conducted in 138 schools. Results indicated that the overall level of program adherence was high, with an average of 82.9%. The mean ratings of the program implementation quality were also high. Despite limitations, the findings of this study suggest that the implementation of the Secondary 1 Program (Tier 1 Program) of the Full Implementation Phase was of very high quality. The present findings also provide strong evidence to account for the successful and encouraging outcomes of a major positive youth development program in Hong Kong.


In many instances, the renin-angiotensin system (RAS) and the vasopressinergic system (VPS) are jointly activated by the same stimuli and engaged in the regulation of the same processes.Angiotensin II (Ang II) and arginine vasopressin (AVP), which are the main active compounds of the RAS and the VPS, interact at several levels. Firstly, Ang II, acting on AT1 receptors (AT1R), plays a significant role in the release of AVP from vasopressinergic neurons and AVP, stimulating V1a receptors (V1aR), regulates the release of renin in the kidney. Secondly, Ang II and AVP, acting on AT1R and V1aR, respectively, exert vasoconstriction, increase cardiac contractility, stimulate the sympathoadrenal system, and elevate blood pressure. At the same time, they act antagonistically in the regulation of blood pressure by baroreflex. Thirdly, the cooperative action of Ang II acting on AT1R and AVP stimulating both V1aR and V2 receptors in the kidney is necessary for the appropriate regulation of renal blood flow and the efficient resorption of sodium and water. Furthermore, both peptides enhance the release of aldosterone and potentiate its action in the renal tubules.In this review, we (1) point attention to the role of the cooperative action of Ang II and AVP for the regulation of blood pressure and the water-electrolyte balance under physiological conditions, (2) present the subcellular mechanisms underlying interactions of these two peptides, and (3) provide evidence that dysregulation of the cooperative action of Ang II and AVP significantly contributes to the development of disturbances in the regulation of blood pressure and the water-electrolyte balance in cardiovascular diseases. Angiotensin II (Ang II) is a member of the renin-angiotensin system (RAS), which forms a cascade of highly active biological compounds regulating a variety of physiological functions. Co-activation of the RAS and the vasopressinergic system (VPS) by the same stimuli, and engagement of the same post-receptor intracellular pathways by Ang II and vasopressin (AVP), favors formation of different types of interactions, which may result in additive, synergistic, or antagonistic effects. Both Ang II and AVP directly participate in the regulation of the cardiovascular system. They also have an impact on several other processes, such as metabolism, stress, emotional disorders, and inflammation, which may exert potent secondary effects on the cardiovascular functions. The main purpose of the present review is to draw attention to the interactions of Ang II and AVP in the regulation of the water-electrolyte balance and blood pressure in healthy individuals and in patients with cardiovascular diseases. Specifically, we give a description of the regulation and function of the RAS and the VPS and we focus on the mechanisms underlying the interactions of Ang II and AVP in cardiovascular regulation and on disturbances of these interactions in cardiovascular diseases.Prorenin and renin circulating in the blood are produced mainly in the juxtaglomerular epithelioid (JGE) cells, located in the wall of the afferent arterioles at the entrance to the glomeruli and in close vicinity to the macula densa (MD) cells, and forming together with the MD cells the juxtaglomerular apparatus (JGA) . Renin iOther angiotensin peptides  are generated by aminopeptidases, carboxypeptidases, endopeptidases, and chymase. Prorenin, renin, and angiotensins act by means of specific renin (PRR) and angiotensin receptors, which are both widely distributed in the cardiovascular system and other organs (see below).All components of the RAS are present in the kidney , 8. ReniThe synthesis and release of renin is altered by factors regulating the production of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) and by changes in the intracellular calcium and sodium content. The stimulatory cAMP-mediated effect of β-adrenergic stimulation on release of renin from the JGA cells plays a significant role during the activation of the sympathetic nervous system . ProstanRenin, Agt, ACE, and Ang II receptors are all present in the myocardium. Angiotensinogen is present mainly in the cardiac atria and fibers of the conductive system. The strongest expression of ACE was found in the coronary endothelial cells and cardiac fibroblasts, and weaker expression of ACE was found in the aorta, pulmonary arteries, valves, endocardium, and epicardium –23. AngiAll components of the RAS have been detected in the brain, in particular, in the brain cardiovascular regions, including the paraventricular nucleus, the medullary cardiovascular regions, and the circumventricular organs. There is strong evidence that the intrabrain RAS plays a significant regulatory role in cardiovascular regulation and is significantly affected in cardiovascular diseases –30. For The components of the RAS have been identified in the adrenal medullary chromaffin cells . Signifiat1r) has been mapped to chromosome 3  of hypertensive or myocardially infarcted rats and of rats exposed to oxidative stress or drastic acute and mild chronic stress , 59–65. d artery . Similard artery .The gene for AT2 receptor (AT2R) is located on the X chromosome . The AT2In the cardiovascular system, activation of AT2R exerts opposite effects to those following stimulation of AT1R. After blockade of AT1R, administration of Ang II may result in hypotension, partly mediated by an increased production of BK, NO, and cGMP . In addi+,K+-ATPase and promotes water transport in the rat inner medullary collecting duct. The latter effect can be abolished both by Mas and V2R antagonists, which suggests involvement of AVP in this process i through an effect dependent on the inflow of extracellular calcium via specific N-type and L-type calcium channels and activation of PKC i in conotoxin-sensitive calcium channels. However, the facilitation of the calcium current by Ang II, involving activation of a reserve pool of dihydropyridine sensitive channels, could be also observed after blockade of conotoxin-sensitive channels i. Insulin-mediated ERK1/2 phosphorylation was enhanced whereas Akt-induced and JNK-induced phosphorylations were not altered. The cardiac effects of overexpression of V1aR were reduced by inhibition of the Gαq/11 transduction pathway  and that this effect can be abolished by pretreatment with specific antagonists of AT1R or V1R [Several studies have provided evidence that the joint action of Ang II and AVP is necessary for the appropriate regulation of the vascular tone, cardiac contractility, and the release of other cardiovascular factors . The authors showed that the beneficial effect of dDAVP crucially depends on cooperation of AT1R with V2R as blockade of AT1R with candesartan completely abolished the dDAVP urine concentrating effect. In a less severe NaCl-restriction rat model, blockade of AT1R increased the fractional excretion of sodium and decreased urine osmolality. It also reduced expression of AQP2 and AQP3 and downregulated phosphorylated AQP2 (p-AQP2) in the inner renal medulla. In vitro experiments performed in the same study revealed that both Ang II and dDAVP increase AQP2 and cAMP expressions [Some evidence indicates that chronic stimulation of ATR in the kidney may alter the responsiveness of the renal tubules to vasopressin and that stimulation of AT1R potentiates the effect of dDAVP on AQP2 plasma membrane targeting •, 346•. ressions •.Altogether, precise cooperation of Ang II and AVP is necessary for the efficient regulation of blood pressure and body fluid volume. In many instances, the effects of both hormones are significantly modulated by the simultaneous action of Ang-(1-7), mineralocorticosteroids, and other cardiovascular factors. Close cooperation of the RAS and VPS with aldosterone inclines to regard the renin-angiotensin-aldosterone system and the vasopressinergic system as a functional unity. Under physiological conditions, cooperation of Ang II and AVP plays a significant role in the maintenance of cardiovascular homeostasis. Excessive stimulation of the RAS and the VPS may have prolonged negative consequences for the cardiovascular system, resulting from the formation of multiple positive feedbacks between renin, angiotensin II, vasopressin, and aldosterone.Dysregulation of the interactions between the RAS and vasopressin under pathological conditions may significantly contribute to the generation of disturbances in blood pressure regulation and the development of cardiovascular diseases. A rationalized combined treatment with inhibitors of the RAS system and vasopressin antagonists appears to be a promising tool in the therapy of various forms of hypertension and cardiac failure, especially in patients manifesting evident overactivity of the sympathetic component of the autonomic nervous system or excessive stimulation of mineralocorticoid receptors.