Previous studies mostly focused on the estimation of the content and storage of PhytOC, while it remains unclear about how the management practices affect the PhytOC content and whether it varies with stand age. Moso bamboo (Phyllostachys heterocycla var. pubescens) has a great potential in carbon sequestration and is rich in PhytOC. Here, we selected four management treatments, including control (CK), compound fertilization (CF), silicon (Si) fertilization (SiF) (monosilicic acid can form phytoliths through silicification), and cut to investigate the variation of phytoliths and PhytOC contents in soil, leaves, and litters, and their storage in Moso bamboo forests. In soil, the SiF fertilizer treatment significantly (P < 0.05) increased phytolith content, PhytOC content, and storage compared to CK, while there were no significant differences between the treatments of CF and cut. In leaf, compared with CK, phytolith content of the second-degree leaves under SiF and the first-degree leaves under cut treatment significantly increased, and the three treatments significantly increased PhytOC storage for leaves with three age classes. In litter, the phytolith and PhytOC contents under the three treatments were not significantly different from that under the CK treatment. The PhytOC storage increased by 19.33% under SiF treatment, but significantly decreased by 40.63% under the CF treatment. For the entire Moso bamboo forest ecosystems, PhytOC storage of all the three management treatments increased compared with CK, with the largest increase by 102% under the SiF treatment. The effects of management practices on the accumulation of PhytOC varied with age. Our study implied that Si fertilization has a greater potential to significantly promote the capacity of sequestration of carbon in Moso bamboo forests.Phytolith-occluded carbon (PhytOC), a promising long-term biogeochemical carbon sequestration mode, plays a crucial role in the global carbon cycle and the regulation of atmospheric CO Phytoli4SiO4) . During 4SiO4) . PhytOC 4SiO4) . PhytOC 4SiO4) , implyin–1 year–1, accounting for 37% of the global average SOC accumulative rate. –1 year–1 in Lei bamboo forest soil. 6 t year–1 of PhytOC was stored in the upper soil of the Loess Plateau in China. –1, respectively. Therefore, the accumulation of soil PhytOC plays an important role in sequestering atmospheric CO2.Previous studies have indicated that the accumulation and distribution of soil PhytOC depend not only on phytolith input from plant’s litter but also on phytolith outputs such as phytolith stability, harvesting loss, and phytolith transport . Parr an9 Mg CO2 year–1, equivalent to 11% of the current increase in atmospheric CO2 , Hangzhou City, Zhejiang Province, in southeastern China . This re–1, with a mean DBH of 9.1 cm. The Moso bamboo forests have few understory shrubs and grasses. The sample plots were established in 2010, no tillage was applied, and the understory vegetation was retained.The experimental sites were located at the southeastern Lin’an . The soiThe experiment was conducted from August 2016 to August 2019.Four treatments, including compound fertilizer (CF), Si fertilizer (SiF), Cut (harvesting), and Control (CK), were deployed in the experimental sites in 2016. The detailed treatments are:(i)–1, twice a year). The composition of compound fertilizer was N 13%, P 3%, K 2%, amino acid ≥ 8%, organic matter ≥ 15%, and humic acid ≥ 10%.Compound fertilizer (CF): Normal cut  and compound fertilizer application –1, twice a year). The composition of Si fertilizer was C concentration of 7 g kg–1 and SiO2 concentration of 723 g kg–1.Si fertilizer (SiF): Normal cut  and Si fertilizer application Cut: Intensive cut  and no fertilization.(iv)Control groups (CK): normal cut and no fertilization.A completely randomized block design with four management treatments and three replicates were deployed, and there were a total of 12 experimental plots (30 m × 30 m). To reduce the interference from the Moso bamboo rhizome spread to the adjacent plots, a 5-m-wide buffer zone was set up between every two experimental plots. The treatments were applied to the entire experimental plot, but the sample data were only collected from the center of each plot (20 m × 20 m).3 volume. The wet soil weight was measured in each corer, and then the soils were dried at 105°C for 24 h to a constant weight. The water content (%) was then calculated.Within each experimental plot, soil samples were taken from the 0–20 and 20–40-cm layers from five randomly selected points along two diagonal lines, and then mixed to form a composite sample for each layer. The samples were stored in clean plastic bags then brought back to the laboratory. Visible roots and plant fragments (>2 mm diameter) in soil were removed. The soil samples were then air dried at room temperature and ground to pass through a 2-mm sieve for chemical analysis. The soil samples for determining bulk density were collected using a bulk density corer (5.2 cm height and 3.5 cm radius) with a 100 cmThe DBH of all bamboo culms with different ages in the 30 m × 30 m plots was measured, and the mean DBH in each age class was calculated. Ten bamboo culms close to the average DBH were selected to sample the bamboo leaves for each age class. The leaves were collected using a pruning shear, and the leaves from each age class were mixed. The leaf samples were brought back to the laboratory and rinsed with deionized water. The leaf samples were first dried at 105°C for half an hour and then further dried at 70°C to a constant weight and weighed. The leaf samples were ground as powders and passed through a 100-mesh sieve for chemical analysis.We also collected all the dead branches and leaves  in three randomly selected 1 m × 1 m plots in each sample plot. The litter samples were stored in sealed plastic bags and weighed. The litter samples were brought back from the field and washed with deionized water, first dried at 105°C, further dried at 70°C to a constant weight, and then weighed. The dried samples were also ground to pass through a 100-mesh sieve for chemical analysis.In our study, the selected physicochemical properties of soil samples were measured using the following methods. Soil pH was determined using an acidity meter, namely, using a pH meter at a soil:water ratio of 1:2.5 (w/v). Soil moisture content was measured gravimetrically. The soil bulk density was determined using the equation below:–3), G is the wet soil weight in a corer (g), V is the volume of the corer (200 cm3), and W is the water content (%).where BD is bulk density (g.cm4F (0.03 mol⋅L–1) and HCl (0.025 mol⋅L–1), and then the available P was measured colorimetrically using a spectrophotometer. The available K was determined using the ammonium acetate extraction flame photometer method. SOC’s content was oxidized by a certain amount of standard potassium dichromate solution and concentrated sulfuric acid under heating conditions, titrated by ferrous sulfate, and calculated by the consumed potassium dichromate , i is the soil profile layer (1: 0–20 and 2: 20–40 cm), Ci is the SOC content of layer i (g kg–1), Di is the soil thickness of layer i (cm), and Bi is the bulk density of layer i (g cm–3).where C3 and 4.8 mL of HCl in the digestion tube in the microwave digester. Then the liquid was transferred to a centrifugal tube for centrifugal cleaning. The extracted phytolith was placed in an oven, dried at 65°C for 48 h to a constant weight, then weighed  were added into a digestion tube. The digestion tube was moved to a microwave digester for digestion; then the liquid was transferred to a centrifugal tube for centrifugal cleaning (The method of extracting phytolith from leaves and litter was slightly different from the above method. Soil samples (0.3 g), 5 mL of HNOcleaning .–1 NaOH, shake well, and let it remain for 12 h. The solution was then transferred to a 30-mL glass centrifuge tube, 1 mL of 0.8 mol⋅L–1 K2Cr2O7 and 4.6 mL of H2SO4 were added, shaken gently, and placed in a 98° boiling water bath for 1 h. Finally, we cooled it and shook well at a constant volume, and took the supernatant for colorimetric determination after low-speed centrifugation. .PhytOC was determined by alkali fusion spectrophotometry according to In order to characterize the capacity of phytolith carbon sequestration, two parameters are selected: one is carbon content in phytolith and the other is PhytOC. Because different management practices can affect the phytolith content, then they will affect the carbon content in phytolith. In addition, PhytOC storage and SOC storage are two different ways of carbon sequestration, so it is meaningful to study the influence of different management practices on the sum of the two ways of carbon sequestration.Soil phytolith concentration, C concentration in phytolith, PhytOC concentration, and soil PhytOC storage were calculated using the following equations:i is the soil profile layer (1: 0–20 and 2: 20–40 cm), thi is the thickness of each soil layer (cm), and BDi represents the soil bulk density for each layer (g cm–3).where Plant phytolith concentration, C concentration in phytolith, and PhytOC concentration were calculated the same as the soil. The PhytOC storage was calculated as follows:The data presented in this paper were the average value of three replicates. Before performing the analysis of variance (ANOVA), the normality and homogeneity of variance were tested. ANOVA was conducted to examine factors and their interactive effects on the SOC concentration and storage, phytolith concentration, C concentration in phytolith (density of carbon contained in phytoliths), and the PhytOC concentration (density of carbon contained in the soil samples) and storage in Moso bamboo forest soils. When the ANOVA analysis indicated a significant treatment effect, the least significant difference (LSD) test was utilized to separate the means. An alpha level of 0.05 for significance was used in all statistical analyses, unless mentioned otherwise. The linear relationship between phytolith concentration and PhytOC storage in soil was determined. All statistical analyses were performed using R statistical software (R v3.2.1) .–1, respectively. Compared with CK, SOC increased under SiF but decreased under CF and Cut treatments. The SOC concentration and storage under SiF significantly increased by 32.3 and 38.9%, respectively, compared with CK  than that under CK, while there were no significant differences among three treatments. For the second-degree leaves, the phytolith content under SiF treatment was significantly higher than that under CK and CF treatment, while there were no significant differences with the cut treatment. For the third-degree leaves, the phytolith content was not significantly different among the four treatments. For litters, although the phytolith content was higher under the three treatments, the difference was not significant compared with the CK  and 76.2% in the subsoil layer (20–40 cm) . The phyh the CK .–1 under four management practices and significantly increased under the application of the SiF treatment by 133% in the topsoil layer and 394% in the subsoil layer compared with CK, respectively  treatment and 53.68 CO2-eq Mg ha–1 under Si3 (1.125 t ha–1) treatment. p > 0.05). The analysis of SOC storage showed that the application of SiF could improve soil fertility and thus significantly increase SOC storage in Moso bamboo forests. The result coincided with a previous study . In Xu’sIn this study, phytolith contents in both soil and leaves increased under all the three management treatments compared with CK, and significant differences were found under SiF treatment. SiF can significantly increase the available Si content in soils and thus the plant organs of Moso bamboo forests, which can promote the formation of phytolith since Si is an important component in phytolith. This pattern is in accordance with a recent study  that hasWe also found that the increase in phytolith content in soil was much greater in leaves and litter under the three treatments compared with the control. This can be explained by the transpiration of leaves that can drive the Si transport and deposit to the root, stem, leaf, and shoots of Moso bamboo in the form of monoclinic acid. Thus, the Si fertilization can significantly increase the Si contents in plant organs, and then through litterfall and its decomposition, the soil phytolith content could also increase. It is necessary to further explore the effects of Moso bamboo litter on the carbon sink of bamboo forest ecosystems to help clarify the relationship between carbon flow between soil and vegetation components, which provides an essential basis for understanding the carbon sink potential of bamboo forest ecosystems . Our res2 per unit area of bamboo leaves, while the change in atmospheric CO2 concentration affects the formation and size of phytoliths by affecting the photosynthetic rate of plants  under the treatment of SiF, but no significant difference was found in the leaves and litters. This was probably because the application of SiF increased the absorption of soluble Si by higher plant roots, and then the effect was transported to other organs such as stems, leaves, and roots, through the transduction tissue, and finally precipitated in the plant cells and came down  In soil, compared with CK, phytolith content and PhytOC storage increased under the three management treatments, both in the topsoil and subsoil layer, and the treatment of SiF had achieved statistically significant increase. The management effects on overall PhytOC storage can be ranked as: SiF > CF > cut > CK. (ii) In leaf, compared with CK, the phytolith content had all increased under the three treatments, and the management effects on overall PhytOC storage varied as a following trend: SiF > CF > cut > CK. Importantly, the phytolith content in the leaves under different treatments varied with age. Compared with CK, the management treatments showed no significant impacts on the phytolith content in the third-degree leaves; the SiF treatment significantly increased phytolith content in the second-degree and the first-degree leaves. (iii) In litter, the management effects on PhytOC storage and phytolith content were similar. Both decreased under the treatment of CF and cut, but increased under the SiF treatment. The management impacts on overall PhytOC storage varied in the following order: SiF > CK > cut > CF. (iv) For the entire Moso bamboo forest ecosystems, PhytOC storage under the three management treatments increased significantly compared with CK, but there were no significant differences between CF and cut treatments. Our results suggested that Si fertilization is an effective way to promote the PhytOC sequestration in Moso bamboo forests via improving the phytolith accumulation.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Apis mellifera)for their complete development need to be supplied through food sourcesavailable in the environment, since honeybees are insects that dependdirectly on blossoming food sources. However, at certain times a food-supplyreduction can promote nutritional stress, thus necessitating foodsupplementation for maintenance or production stimulus of the colonies.Thus, the determination of optimal energy supplementation can assist in themaintenance and production of colonies. The nutritional requirements of honeybees (Apis mellifera beehives were used (with five beehivesper treatment): CTL, control (without feeding); SJ, sugarcane juice; SS,sugar syrup; and IS, inverted sucrose. We evaluated the food consumption,population development, and physiological state (expression of vitellogeninand hexamerin 70a genes) of each colony.Twenty 2, sealed and openbrood, respectively). Furthermore, this diet ensured that the colonies werein a good physiological state, as bees fed this diet presented the highestrelative expression levels of vitellogenin and hexamerin 70a among all thediets tested.The results showed that the supplementation of colonies with sugar syrupresulted in an intermediate consumption level (894.6 ± 291 mL) and betterdevelopment (384.9 ± 237.3 and 158.3 ± 171.6 cmTherefore, sugar syrup is concluded to be the best artificial energetic foodfor use in the supplementation of honeybee colonies. Apis mellifera) for theircomplete development, maintenance, reproduction, production and longevity need to besupplied through food sources available in the environment [. In nature, A. melliferabees meet all their nutritional needs through the ingestion of nectar and pollen[All of the nutritional needs of honeybees , UNESP, onLageado Experimental Farm, Botucatu, SP, Brazil. Queens were replaced in allcolonies two months before the experiment. The food treatments used were thefollowing: control (CTL), in which no artificial food was provided; feeding withsugarcane juice (SJ) produced in an electric cane mill at a research laboratory;feeding with sugar syrup (SS) prepared using pre-boiled filtered water andsucrose ; and feeding with inverted sucrose (IS) purchased fromAtrium Food Group, Campinas, São Paulo, Brazil (76 % sugar and 24% water).For the field experiment, 20 Food was supplied twice a week in the amount 0.5 L per hive (1 L colony/per week)for a period of 60 days by means of a Boardman artificial feeder. The experimentwas carried out in June and July of 2015. During the experimental period, foodconsumption was measured weekly.Population development, including the numbers of open and sealed areas in onecentral nest structure, was measured monthly in the hives throughout theexperimental period using the methods used and described by Ali . The numThe bees for use in the analysis of the relative expression levels of theselected genes were collected on day 0, and were used as the experimentalcontrol. Collections were also carried out on day 30 and 60. Five worker beeswere collected from the central frame, and were identified as intern bees (I); 5worker bees were also collected that were carrying pollen in their corbicle, andin turn were identified as forager bees (F). During the experimental period, allof the colonies receiving the SJ treatment died, which made it impossible tocollect these bees for analysis. After collection, the bees were immediatelystored in a freezer at -80 °C for future RNA extraction.To analyze the expression of vitellogenin and hexamerin 70a, 5 forager and 5intern bees were randomly collected from each experimental colony andimmediately frozen at -80 °C on days 0, 30, and 60. Total RNA was extracted fromthe heads of 5 bees of each type using 50Amplification was performed by real-time quantitative polymerase chain reaction(RT-qPCR) in a 25µL reaction mixture using the SYBR® Green PCR Master Mix(Applied Biosystems) and 0.2 μM of each primer. The sequences and details of theprimers used are provided in The efficiency of the oligonucleotides (E) was calculated from 4 dilutions ofcomplementary DNA samples  using the formula E = 10(-1/inclination). The quantification of a gene’s relative expression (R) wasdetermined according to Pfaffl ,defininThe data obtained for food consumption, population development, and geneexpression were first tested for normality (Anderson-Darling test) andhomogeneous variances (Levene’s test). When significant deviations (p < 0.05)from these assumptions were detected, the data were compared using thenon-parametric Mann-Whitney test, and the median and interquartile intervals(Q1_Q3) were presented. When no significant deviations from normality orhomoscedasticity were detected, the data were analyzed with one-way ANOVA, andthe mean ± standard deviation values were presented. P-values below 0.05 wereconsidered significant. All statistical analyses were performed using thestatistical software Minitab.The respective weekly consumptions of SJ, SS, and IS were 0.994.8 ± 310, 894.6 ± 291,and 433.9 ± 227.6 mL. During the experimental period four colonies under SJtreatments absconded. The results of the physicochemical analyses of the different foods are presented in-1) of all the foods tested . The dry mattervalues of SJ and SS were lower than that of IS, indicating their higher moisturecontent. The analysis of the total reducing sugars in each food type found a higherSS value (41.52 ± 2.8%), which differed significantly from those detected for SJ(21.15 ± 1.6%) and IS (0.82 ± 0.01%). The calorimetric analysis of the foods showed that SS presented the highest energeticvalue , whereas in the SS treatment the upregulation of this gene (i.e.increased relative expression) was noted. Among the forager bees sampled at the sametime, only those treated with IS presented downregulation of this gene, which showedthat gene expression patterns differed between the intern and forager bees.When analyzing intern bees at 60 days, the expression of this gene was upregulated inall treatment groups, although the CTL and SS treatments presented relatively higherexpression levels compared to those in the IS treatment . The bees fed SS showed greater expressionof this gene in comparison to those in the other treatments, similarly to the internbees collected at 30 days. However, among the forager bees collected at the sametime, only those treated with SS presented downregulation of this gene in relationto the control.When changing the focus of the data analysis and comparing the results obtained fromintern and forager bees between 30 and 60 days under the different treatments tocheck for changes in the gene expression pattern after 60 days of feeding, it wasobserved that all the analyzed treatments differed in their relative expressionlevels (p < 0.05). In the CTL and IS treatments, both intern and forager beesshowed increased expression of the vitellogenin gene during the experiment(P<0.05). However, the contrary occurred under the SS treatment, namely greaterrelative expression at 30 than at 60 days in both intern and forager bees.Comparing the intern and forager bees at 30 and 60 days, in all treatments except SSthere were lower relative expression levels of the hexamerin 70a gene  in the iAt 60 days, this gene presented upregulation in both the forager and intern bees inall treatments, but the intern bees showed relatively higher expression levels ofthe hexamerin 70a gene than the forager bees in all treatments.Feeding artificial energetic foods to honeybee colonies during the off-season ensuresthe correct annual operation of the colony. For this to be effective, it isnecessary to choose the best energetic food to offer the bees to ensure the properdevelopment of a colony for the beekeeper. The lower consumption of inverted sucrosein the present study can be linked to the higher dry matter percentage and lowerwater content (24% water), since bees collect nectar as a natural energetic sourcewhose water content exceeds 24% .The dry matter data followed contrary trends among treatments in relation to thedifferent food types, since the moisture content of the food is inverselyproportional to dry matter , 24. TheCastagnino  showed tThe loss of four colonies subjected to the SJ treatment over the experimental periodprobably occurred because the sugarcane juice (the diet offered to bees in the SJtreatment) may have undergone fermentation at ambient temperature . Given tThe analysis of intern bees at 30 days demonstrated an upregulation in vitellogeninexpression in the SS treatment only. At the same moment and treatment the hexamerin70a relative expression obtained a much greater value when compared with othertreatments. This shows that sugar syrup had a more direct influence on intern beesthan the other foods provided throughout the experimental period. This result may berelated to several factors, such as energetic value and the maintenance of foodintegrity and quality at room temperature.The vitellogenin expression levels observed after 60 days of feeding suggested thatthe SS treatment had a greater influence on the expression of this gene than theother diets, and it also facilitated better population development of the colonysince the values of almost all of the performance parameters assessed were higher inthis treatment compared to those in the other treatments. The forager bees, whichlive for approximately 21 days, presented less relative expression of this gene thanthe intern bees, which were less than 15 days old, at both 30 and 60 days. This mayhave been due to the fact that there was a higher concentration of juvenile hormonein the hemolymph of the older bees, which may have influenced their biosynthesis ofvitellogenin. As noted earlier, vitellogenin is a protein related to the preventionof oxidative stress since it is a zinc carrier, while low levels of this protein cancompromise the immune system [The results of this study demonstrated that the supplementation of honeybee coloniesin the field during the off-season with sugar syrup results in an intermediate levelof consumption of this food by them and greater colony development, and also ensuredthat the bees were in a better physiological state. Therefore, it is demonstratedthat sugar syrup is the most beneficial artificial energetic food tested in thisstudy.CTL: control; F: forager bees; I: intern bees; S: inverted sucrose; RT-qPCR:real-time quantitative polymerase chain reaction; SJ: sugarcane juice; SS: sugarsyrup.


To contribute to the WHO initiative, VISION 2020: The Right to Sight, an assessment of global vision impairment in 2020 and temporal change is needed. We aimed to extensively update estimates of global vision loss burden, presenting estimates for 2020, temporal change over three decades between 1990–2020, and forecasts for 2050.We did a systematic review and meta-analysis of population-based surveys of eye disease from January, 1980, to October, 2018. Only studies with samples representative of the population and with clearly defined visual acuity testing protocols were included. We fitted hierarchical models to estimate 2020 prevalence  of mild vision impairment , moderate and severe vision impairment (<6/18 to 3/60), and blindness ; and vision impairment from uncorrected presbyopia . We forecast estimates of vision loss up to 2050.In 2020, an estimated 43·3 million (95% UI 37·6–48·4) people were blind, of whom 23·9 million  were estimated to be female. We estimated 295 million (267–325) people to have moderate and severe vision impairment, of whom 163 million  were female; 258 million (233–285) to have mild vision impairment, of whom 142 million  were female; and 510 million (371–667) to have visual impairment from uncorrected presbyopia, of whom 280 million  were female. Globally, between 1990 and 2020, among adults aged 50 years or older, age-standardised prevalence of blindness decreased by 28·5% (–29·4 to −27·7) and prevalence of mild vision impairment decreased slightly , whereas prevalence of moderate and severe vision impairment increased slightly . In this period, the number of people who were blind increased by 50·6% (47·8 to 53·4) and the number with moderate and severe vision impairment increased by 91·7% (87·6 to 95·8). By 2050, we predict 61·0 million (52·9 to 69·3) people will be blind, 474 million (428 to 518) will have moderate and severe vision impairment, 360 million (322 to 400) will have mild vision impairment, and 866 million (629 to 1150) will have uncorrected presbyopia.Age-adjusted prevalence of blindness has reduced over the past three decades, yet due to population growth, progress is not keeping pace with needs. We face enormous challenges in avoiding vision impairment as the global population grows and ages.Brien Holden Vision Institute, Fondation Thea, Fred Hollows Foundation, Bill & Melinda Gates Foundation, Lions Clubs International Foundation, Sightsavers International, and University of Heidelberg. Towards universal eye health: a global action plan 2014–2019 by the World Health Assembly renewed ideals and strategies for Member States to amplify initiatives to prevent vision impairment and promote low vision rehabilitation in their populations.VISION 2020: The Right to Sight, a joint global initiative for the elimination of avoidable blindness between WHO and the International Agency for the Prevention of Blindness, has galvanised efforts to systematically eliminate avoidable blindness.Global Vision Database, a continuously updated, comprehensive, online database storing worldwide ophthalmic epidemiological information. In a previous report, we estimated that in 2015, 36·0 million people were blind, 217 million had moderate and severe vision impairment, 188 million had mild vision impairment, and 667 million additional people (aged ≥50 years) had vision impairment from uncorrected presbyopia.World report on vision, published by WHO in 2019.country-specific data online, searchable by level of vision impairment, age, and sex.The Vision Loss Expert Group (VLEG) populates and curates the Evidence before this studyThe Vision Loss Expert Group (VLEG) previously published global, regional, and country-level estimates of mild or more severe distance vision impairment from 1990 to 2015. They found an overall decrease in age-standardised prevalence of distance vision but an increase in total people with vision loss. In collaboration with the VLEG, the Global Burden of Disease Study (GBD) has produced annual updates of estimates of vision impairment, most recently in 2019. An important contribution to the WHO initiative, VISION 2020: The Right to Sight, these studies are unique in providing granular estimates that are sex, age, and country specific, and also assess temporal trends.Added value of this studyThis updated assessment of global vision impairment contributes to VISION 2020: The Right to Sight by providing up-to-date global and regional sex-specific and age-specific estimates of vision impairment, analyses of how vision impairment rates and cases have changed over time, and projections by region to 2050. The current study also allows us to assess the World Health Assembly 2013 resolution to decrease avoidable moderate or worse distance vision impairment by 25% from 2010 to 2019. Our results suggest that total cases of moderate or worse distance vision have increased since 2010, and therefore, in terms of crude prevalence, the target was not reached.Implications of all the available evidenceDespite a reduction in global age-standardised prevalence of blindness, the crude prevalence is increasing, and with an ageing and growing population, vision impairment remains an urgent and increasingly important public health priority. We are currently investigating the causes of vision impairment, and more directly assessing temporal changes in avoidable vision loss.As countries progress on the spectrum of socioeconomic development and life expectancies increase, the disease burden is shifting from communicable conditions to non-communicable and age-related conditions. The blinding ophthalmic conditions that are manifesting in this so-called epidemiological transitionOur 2015 report concentrated on blindness and moderate and severe vision impairment, with little data pertaining to mild vision impairment and vision impairment from uncorrected presbyopia. Since then, in collaboration with the Global Burden of Disease Study (GBD), the Global Vision Database has been extensively updated and revised with increased granularity of the available worldwide ophthalmic epidemiological information, permitting a more precise estimate of the global vision loss burden in 2020 and assessment of temporal changes. Additionally, we can describe vision loss in terms of years lived with disability (YLDs).Preparation of data included first a systematic review of published population-based studies of vision impairment and blindness by the VLEG, that also included grey literature sources. Eligible studies from this review were then combined with data from Rapid Assessment of Avoidable Blindness (RAAB) studies by VLEG and finally data from the US National Health and Nutrition Examination survey and the WHO Study on Global Ageing and Adult Health were contributed by the GBD team. These stages are explained in more detail as follows.RAAB repository. We included studies that met the following criteria: visual acuity data had to be measured using a test chart that could be mapped to the Snellen scale, and the sample had to be representative of the population. Self-report of vision loss was excluded. We used International Classification of Diseases 11th edition criteria for vision loss, as used by WHO, which categorises people according to vision in the better eye on presentation, in which mild vision loss is defined as a visual acuity of 6/18 or better but less than 6/12, moderate vision loss as a visual acuity of 6/60 or better but less than 6/18, severe vision loss as a visual acuity of 3/60 or better but less than 6/60 (hence our definition of moderate and severe vision loss is <6/18 to 3/60), and blindness as a visual acuity of less than 3/60 or less than 10° visual field around central fixation . Vision impairment from uncorrected presbyopia was defined as presenting near vision of worse than N6 or N8 at 40 cm when best-corrected distance visual acuity was 6/12 or better. This definition was used to avoid double counting individuals with both distance and near vision impairment associated with non-refractive causes.In this study, we used population-representative studies as data sources for modelling of vision impairment; more detailed methods are in the The data identification process is summarised in the First, we separated raw data into datasets including so-called vision-loss envelopes for all-cause mild, moderate, and severe vision loss, and blindness. Studies that only reported male and female sex information combined were split into male-specific and female-specific datapoints by identifying within-study datapoints matched by age, year, and location that reported data for male and female prevalence separately, and then we used the log ratio of female to male prevalence from these studies as input data into a mixed-effects meta-regression tool developed by the Institute for Health Metrics and Evaluation (IHME) called MR-BRT . This tool was developed in part to allow for the ability to propagate between-study heterogeneity as part of uncertainty adjustments, and to allow trimming of outlier input data. A detailed description of MR-BRT has been published elsewhere.Disease Modelling Meta-Regression (DisMod-MR) 2.1 modelling is described in detail elsewhere.We ran DisMod-MR 2.1 models for all vision loss severity categories. We used final estimates for vision loss to calculate YLDs on the basis of disability weights assigned to each severity of vision loss, and, finally, adjusted for comorbidity with any causes of non-fatal health loss.Final estimates for GBD 2019 are for the years 1990–2019. To estimate the number of individuals for each severity level for the year 2020, we multiplied 1000 draws of estimated prevalence from GBD 2019 for each location by the 2020 population estimates for each location to calculate the number of affected individuals and 95% uncertainty intervals (UIs) in 2020. We age-standardised our estimates using the GBD standard population  of which were RAAB studies. Maps showing the distribution of RAAB and non-RAAB sources by region are in the Globally, 43·3 million (95% UI 37·6–48·4) people were estimated to be blind in 2020 , of whom 23·9 million  were female .Table 1NIn 2020, we estimated that the largest number of people with blindness resided in south Asia, followed by east Asia and southeast Asia . The cruWe estimated that moderate and severe vision impairment affected 295 million (95% UI 267–325) people in 2020 , with 37We estimated 258 million (95% UI 233–285) people were affected by mild vision impairment in 2020 , of whom 142 million  were female .Table 2NWe estimated 510 million (95% UI 371–667) people were affected by vision impairment from uncorrected presbyopia in 2020 , of whom 280 million  were female . Among tIn 2020, age-standardised prevalence for all severities of vision impairment was higher in females aged 50 years and older than in males of the same age group . This between-sex difference was largest for vision impairment from presbyopia, and smallest for blindness.We estimated that in 2020 the population aged 50 years and older  accounted for 33·6 million  of 43·3 million people who were blind, 206 million  of 295 million people with moderate and severe vision impairment, 143 million  of 258 million people with mild vision impairment, and 419 million  of 510 million people with vision impairment from uncorrected presbyopia . The strTo compare patterns and trends in the prevalence of vision impairment without being confounded by the age structure, we calculated age-standardised prevalence, focusing on older adults (aged ≥50 years), who had the largest burden of vision impairment . In 2020Global age-standardised prevalence of moderate and severe vision impairment was 112 (95% UI 99·0–126) cases per 1000 people in this older age group . The regChange in age-standardised prevalence of mild vision impairment, moderate and severe vision impairment, and blindness in adults aged 50 years and older between 1990 and 2020 is shown in Globally between 1990 and 2020, among older adults, we estimated that age-standardised prevalence of blindness decreased by 28·5% , with the decrease being larger among males  than among females . Change in crude prevalence for those aged 50 years and older for this period was −21·9% (–23·3 to −20·6) in females and −27·4% (–28·7 to −26·2) in males; and for all ages was 4·6% (2·6 to 6·6) for females and −0·7 (–2·6 to 1·1) for males. This reduction among both sexes was noted in all regions, but in particular in south Asia, where a change of −47·6% (–48·4 to −46·9) was observed for both sexes combined in those aged 50 years and older. In this time period, for moderate and severe vision impairment, global estimated age-standardised prevalence among those aged 50 years and older increased slightly by 2·5% , and a more substantial increase was seen among females  than among males . We found considerable inter-region variation in this change—eg, for both sexes combined, south Asia  and southeast Asia  had the most substantial decreases, whereas an increase of 8·5% (7·1 to 9·9) was found for east Asia. For mild vision impairment, age-standardised prevalence reduced slightly by 0·3%  globally and in all regions, with a reduction of 3·1% (–3·7 to 2·4) in males whereas the prevalence in females increased by 1·9% (1·2 to 2·5). For vision impairment from uncorrected presbyopia, we were not able to do global and inter-regional analyses due to sparsity of data.By 2050, the number of people with blindness in the global population is predicted to increase to 61·0 million (95% UI 52·9–69·3). Moderate and severe vision impairment is predicted to affect 474 million (428–518) people, mild vision impairment to affect 360 million (322–400) people, and vision impairment from uncorrected presbyopia to affect 866 million (629–1150) people. A breakdown of estimates by sex is given in GBD Compare tool.GBD has published YLD data for 2019;When ranked against all causes of disease by YLDs in the Global Burden of Diseases, Injuries and Risk Factors Study 2019, blindness and low vision ranked eighth  in the aged 50–69 years age group for both sexes , and fourth  in the aged 70 years and older age group .Towards universal eye health: a global action plan 2014–2019.vs other competing priorities); awareness of the population that the services are available; perceived need for services among the population ; and the extent to which barriers such as cost of travel, fees, and fears can be overcome. Sustainability of the efforts put into provision of these services is one of many long-term needs. Although the observed decrease in age-adjusted burden of vision impairment suggests systematic improvements are occurring, more improvements are needed to alleviate the problem of vision impairment to the extent envisioned in the global action plan. These measures would need to address both the supply of services and factors affecting demand for the services.In 2013, the World Health Assembly adopted resolution 66.4, which included However, encouragingly, the age-adjusted prevalence of blindness was estimated to have reduced by 27·0% (95% UI −27·8 to −26·1) globally between 1990 to 2020. Conversely, the age-adjusted prevalence of moderate and severe vision impairment increased slightly . This slight increase is probably due to resources for cataract being directed to more severe disease .This study highlights the large burden of mild, moderate, and severe vision impairment that could become overwhelming as the global population ages in both high-income countries and low-income and middle-income-countries. While low-income and middle-income countries are challenged with detecting and delivering care to those already in an advanced state of vision loss, high-income countries face service delivery challenges to manage chronic age-related eye diseases in an ageing population with increasing life expectancy.World report on vision, based on the VLEG's 2015 estimates.The VLEG contributed data on vision impairment prevalence to WHO's recent The strengths of this updated review and analysis for 2020 include the substantial addition of new data sources and the wider geographical region that these sources cover. In particular, the contribution of the RAAB surveys, most of which took place in low-income and middle-income countries, has been enhanced by the extraction of data disaggregated into smaller age categories, which has greatly strengthened the fitting of age patterns to the data from these surveys. However, our study also had several limitations. For example, several regions, such as central sub-Saharan Africa, central and eastern Europe, and central Asia, still have little or no population-based data, so estimates in these regions rely on extrapolation from other regions. Sparse data also restricted our ability to estimate temporal trends. Few data were available for children, and although we were able to include data from the Refractive Errors Studies in Children, which involved robust population-based sampling,For the first time in our reports, we have incorporated YLDs into our analysis. Although VLEG remains concerned over the disproportionally low disability weights assigned to blindness and vision impairment,World report on vision observes that “Concerted action during the past 30 years has yielded many successes: global advocacy efforts have been launched; World Health Assembly resolutions adopted; and actions plans implemented. Recent scientific and technological developments promise to further accelerate these advances. Nonetheless, progress is not keeping pace with population eye care needs.”The WHO rb@rupertbourne.co.ukCorrespondence to: Prof Rupert RA Bourne, Vision and Eye Research Institute, Anglia Ruskin University, Cambridge CB1 1PT, UK Global Health Data Exchange GBD 2019 website.To download the data used in these analyses, please visit the


Helianthus annuus L.) and its wild progenitor  to reconstruct phylogeographic relationships and population genetic/demographic patterns across sunflower. In common sunflower, south-north patterns in the distribution of nucleotide diversity and lineage splitting indicate a history of rapid postglacial range expansion from southern refugia. Cultivated sunflower accessions formed a clade, nested among wild populations from the Great Plains, confirming a single domestication event in central North America. Furthermore, cultivated accessions sorted by market type  rather than breeding pool, recapitulating the secondary development of oil-rich cultivars during its breeding history. Across sunflower, estimates of nucleotide diversity and effective population sizes suggest that cultivated sunflower underwent significant population bottlenecks following its establishment ~5000 years ago. The patterns inferred here corroborate those from previous studies of sunflower domestication, and provide a comprehensive overview of its evolutionary history.Patterns of genetic variation in crops are the result of selection and demographic changes that occurred during their domestication and improvement. In many cases, we have an incomplete picture of the origin of crops in the context of their wild progenitors, particularly with regard to the processes producing observed levels of standing genetic variation. Here, we analyzed sequence diversity in cultivated sunflower ( Helianthus annuus L.).Patterns of genetic variation in cultivated plants are the product of multiple processes that have occurred over their evolutionary histories. Gaining a comprehensive understanding of these patterns and the underlying processes requires reconstructing them within the broader context of the wild species from which they are derived. Such species-wide assessments can provide inferences into the ancestral lineages that gave rise to early domesticates and modern cultivars, and yield insights into the factors explaining the distribution of genetic diversity across gene pools. Such knowledge also has practical value, and can be applied to identify sources of novel alleles that should be preserved in germplasm collections and which may be of value in modern breeding programs ,2,3,4. HCommon sunflower is a widely distributed annual herb whose native geographic range is centered in the Great Plains region of the United States and Canada . SunflowThis historical account of the evolutionary history of sunflower serves as the basis of hypotheses concerning the expected population structure and levels of standing genetic variation across its gene pool. Previous studies have sought to infer these patterns in sunflower at various scales, and have shed light on certain aspects of its origin and subsequent evolution. For example, broad examinations across common and cultivated sunflower have provided strong evidence for a single domestication event ,14,15, aTo date, however, attempts to infer patterns of population divergence and population structure in common sunflower (particularly from a phylogeographic perspective) have been somewhat limited, and efforts to formally reconstruct the demographic history of sunflower domestication are lacking. As such, a number of important issues have not been addressed. For example, given that common sunflower populations currently span areas with widely varying climatic conditions during the Last Glacial Maximum , In this study, we sought to characterize the phylogeographic history of sunflower. We used genotyping-by-sequencing (GBS) to examine a panel of accessions that span the latitudinal range of common sunflower and the breadth of cultivated sunflower diversity to: (1) reconstruct the postglacial migration history of common sunflower; (2) identify patterns of genetic relatedness and structure across the various breeding pools of cultivated sunflower; and (3) gain insights into the history of demographic changes associated with domestication and subsequent improvement.Helianthus argophyllus and Helianthus petiolaris), to root phylogenies and polarize SNPs for the downstream analysis (see below). Seeds were sown in flats, and leaves were sampled from a single individual per cultivated sunflower line and up to 18 seedlings per wild sunflower accession. Genomic DNA was extracted from collected leaves using a modified CTAB protocol [We obtained seeds of cultivated and common sunflower from the USDA North Central Regional Plant Introduction Station  in high-output mode and set to produce 75 bp single-end reads. All library preparation and sequencing was performed at the Georgia Genomics and Bioinformatics Core .DNA extractions were prepared for sequencing following a two-enzyme GBS protocol  using thWe used iPyrad version 0.9.16  to proceH. annuus; 2 H. argophyllus, 3 H. petiolaris samples) at a minor allele frequency greater than 1% (MAF > 0.01). The sample coverage threshold in this dataset was chosen because it allowed for the retention of lower coverage, high mutation rate sites which are useful in resolving recent divergences [H. petiolaris and argophyllus . The reduced sample size and sample coverage thresholds of the “ingroup_dadi” dataset were chosen as they increased the number of segregating sites available for demographic analysis. Furthermore, the relatively low MAF and MAC thresholds of the “ingroup” datasets were chosen to allow for the inclusion of rare variants which provide greater resolution of genetic structure and demographic events [Phylogenetic analyses were conducted on the “phylogenomics” dataset composed of biallelic SNPs present in ≥ 50% of ingroup and outgroup samples , as well as the wild populations, separately. Differences in π among breeding pools were assessed by computing the 95% confidence intervals from 1000 bootstrap replicates of per-site estimates of π using the “boot” and “boot.ci” functions in the R [boot [Estimates of mean nucleotide diversity (π) across all sites were calculated with VCFtools to identify patterns in the distribution of genetic diversity across breeding pools within in the R  package  R [boot .ST and FIS) were estimated using all sites with the hierfstat R package [ade4 [ST [hierfstat R package [geosphere R package [6 Monte Carlo simulations. Clinal trends in π were investigated with linear regression, treating latitude and longitude as fixed effects using the “lm” function in R. AMOVA was conducted using the poppR package in R [We then estimated patterns of genetic diversity across wild sunflower populations. Global population genetic parameters  as implemented in the R package LEA [We estimated individual ancestry coefficients with fastSTRUCTURE 1.0  and ADMIkage LEA .We modeled the divergence history between wild and cultivated sunflower using the diffusion approximation approach implemented in δaδi 2.0.3 . We formeasySFS (https://github.com/isaacovercast/easySFS), sampling 24 and 30 haplotypes from the cultivated and wild lineages, respectively, to maximize the number of segregating SNPs for analysis [dadi_pipeline (https://github.com/dportik/dadi_pipeline), described in Portik et al. [dadi_pipeline was run using custom settings  and models were extrapolated to a grid size of 40, 50, 60 points and fitted with Nelder-Mead optimization. Maximum-likelihood parameter estimates from the best replicate run  for each model were used to calculate the Akaike information criterion (AIC) scores for model testing [−9 substitutions/site/generation [6 bp.An unfolded 2D site-frequency spectrum was generated using the program analysis . Model fk et al. . dadi_pi testing  followin testing . Standar testing , which hneration , and an 9 reads were sequenced across 257 samples ; on average, 5.96 × 106 reads were sequenced per sample (range = 3.27 × 106–1.47 × 107 reads). Following quality filtering and processing, we assembled 1.08 × 106 loci; the number of SNPs recovered from these loci are listed in 1.53 × 10H. annuus indicates that primitive domesticated lines and improved cultivars harbor progressively less genetic diversity than their wild progenitor.There were notable differences in nucleotide diversity (π) among breeding pools A, with aST = 0.169) and inbreeding (FIS = 0.177) across and within populations of wild sunflower. FST between populations varied widely . Furthermore, clinal patterns in the distribution of diversity were observed, as indicated by significant declines in π with increasing latitude  and decreasing longitude . AMOVA found that most genetic variation is partitioned within samples , with relatively little variation explained by differences between samples , populations , and genetic clusters . The sum of these results suggest that genetic diversity is continuously distributed across the range of wild sunflower, with the highest levels of diversity being concentrated in populations located in the southeastern portion of the range.We observed moderate genetic differentiation  nested within the New Mexico-Central Great Plains grade A. Four NK , but consistently identified a distinct cluster of cultivated accessions while sorting wild samples into increasingly smaller, geographically defined clusters until K = 17, where all wild samples were sorted by their collecting locality. This fractal pattern of population clustering is consistent with IBD, so we present results from fastSTRUCTURE analyses for K = 2–6, which circumscribe landscape-level, geogenetic clusters  was consistently estimated to have ca. 50% membership in other clusters across all values of K, and samples from the Wyoming population were found to possess 30-40% admixed ancestry at K = 4 and 5  and, for both analyses, ancestry assignments at K > 3 were difficult to interpret. That being said, we present fastSTRUCTURE results for K = 2–3, which reveal subtle, biologically interpretable structure within the cultivated lines. At K = 2, a single Native American landrace accession (Hopi Dye) is inferred as its own cluster, with three other Native American landrace accessions  sharing some ancestry (< 20%) with the Hopi Dye cluster  rather than breeding pool ; shrubsulustris , Viburnutanoides , Viburnu complex , and theViburnum ); and trsacharum ,68, Carynd ovata ,70, Fagundifolia ,71, and  strobus ,73).Paleoecological studies provide a finer resolution to the approximate locations of refugial areas during the late Pleistocene, and suggest that many of the aforementioned species may have persisted in macrorefugia distributed along the Gulf Coast , with coK . As sucK B. Our fiPatterns of divergence and population structure in cultivated sunflower are complex, but largely reflective of its domestication and breeding history. Cultivated accessions form a strongly supported clade, nested among wild sunflower populations from the central Great Plains A, and esPatterns of phylogenetic and population structure outside of the early diverging landraces become apparent when the cultivars are coded by market type  rather than breeding pool  . The sore)) between wild and cultivated sunflower [Domestication and improvement have generated large differences in observed levels of genetic diversity in the wild and cultivated sunflower breeding pools. Unsurprisingly, exotic and elite lines were found to harbor ca. 60% and 50% of the nucleotide diversity (π) present in wild sunflower, respectively A. These unflower ,20,21,84Demographic reconstructions provide some insight into the timing and order of these changes in genetic diversity . For exaIn sunflower, moderate rates of gene flow from the wild into cultivated breeding pools do not appear to have strongly influenced current effective sizes , which m


In addition, the byproduct of ammonia generation permits possible reuse of spent IFGEM as soil amendments in crop land, gardens and yards, and green roofs for urban farming. Findings may help secure urban food supply chains and harmonize nutrients, soil, water, and waste management in different urban environments.Ensuring urban areas have access to clean drinking water, safe food supply, and uncontaminated water bodies is essential to the good health of millions of urban residents. This paper presents the functionality of Iron Filings-based Green Environmental Media (IFGEM) in terms of nutrient removal efficiencies to support water quality management and urban farming. IFGEM uses recycled materials such as tire crumb and iron filings to help remove nutrients with essential physicochemical properties. In this study, IFGEM were proven effective and sustainable through an isotherm study, a column study of reaction kinetics, and a microstructure examination under various inlet nutrient concentration levels. IFGEMs exhibited over 90% nitrate removal, as well as 50–70% total phosphorus removal, under most inlet conditions. These promising results make IFGEM suitable for treating stormwater runoff, wastewater effluent, and agricultural discharge via varying  One of the issues facing sustainable development is the contradiction between nutrient (nitrogen and phosphorus) depletion in agricultural production2 and nutrient contamination from stormwater runoff, wastewater effluent, and agricultural discharge4. Undesired nutrient loads to natural systems and the built environment create environmental sustainability concerns in terms of ecosystem degradation due to eutrophication and loss of biodiversity6. On the other hand, the rapid growth of the global population constantly increases demands for food production, and modern agriculture largely relies on mining-based fertilizers, which are facing a depletion issue, particularly for phosphorus7. Through consideration of these intertwined situations, the Environmental Protection Agency8 promulgated regulatory standards for remediating the impacts from the non-point source pollution10 and resolving the contradictory situation in nutrient management.Globalization and urbanization have reshaped human society, producing a set of complex, interdependent, and interrelated problems in a food-energy-water-waste nexus under the constraint of limited natural resources12. However, existing BMPs are becoming less effective due to increased nutrient concentrations and runoff volumes, as well as soil contamination via rapid urbanization14. One solution is to use green sorption media , designed for enhancing nutrient removal both sustainably and cost effectively. However, there are some design complications when attempting to remove multiple nutrients. Phosphorus removal, for instance, mainly depends on high calcium (CaO) content in green sorption media16, whereas, for nitrogen removal, green sorption media would need clay minerals and tire crumb components following the physiochemical approach10. The microbiological processes of nitrification and denitrification are also major approaches for nitrogen removal in moisturized environments18. Thus, the removal processes of phosphorus and nitrogen are relatively separate in green sorption media applications.Best management practices (BMPs) such as filtration basin, grassed swale, green roof, etc., have been used to remediate non-point pollution for decades19. One study evaluated biological phosphorus removal through the use woodchips only, as well as through woodchips with activated alumin/gravel mixture. The mixture showed 19 times greater reduction in total phosphorus, while the woodchip was only able to remove reactive phosphorus (bioavailable ones)20. Overall, metal-based filtration media  are more appropriate for phosphorus removal22 but the nitrogen removal was not considered in this study.Some studies have tried to improve simultaneous nitrogen and phosphorus removal by applying different filtration media layers, one of which is iron-rich sandy loam24 and phosphorus26. However, NZVI have an intensive reaction rate and may raise some public health concerns when considering their application in retrofitted BMPs27. In addition, nano materials are normally expensive for large scale applications. However, iron filings, as an industrial byproduct, have no such concerns. Hence, green sorption media that can simultaneously remove and even recover nitrogen and phosphorus via just physiochemical reactions are more valuable, cost-effective, and sustainable to implement in areas that might not be suitable for microbiological reactions. There might be a potential candidate to be mixed with existing green sorption media known as Bio-sorption Activated Media (BAM) for the enhancement of nitrogen and phosphorus removal from stormwater runoff33.In recent years, nanoscale zero valent iron (NZVI) particles have been studied for their promising removal of nitrateThis study presents a preliminary evalution of the ability of a mixture of iron filings with clay and sand, called Iron-Filings based Green Environmental Media (IFGEM), to provide simultaneous removal of nitrogen and phosphorus via physicochemical processes. To gain a fundamental understanding of how IFGEM mix works and confirms their applicability, the objectives of this study are thus to: (1) conduct an isotherm study for IFGEM to gain understanding of their absorption and adsoption characteristics for simultaneous nitrate and phosphorus removal under neutral pH and room temperature conditions; (2) carry out a column study to test their nutrient removal efficiencies under various influent concentrations; (3) assess the holistic performance of IFGEM with the aid of an imaging analysis technique for discussing their potential for nutrient reuse/recovery.The research questions to be answered include: (1) how would the iron filings interact with different green sorption media components and what are their impacts on nitrate and phosphorus removal? (2) how would the different initial nutrient conditions affect the reaction kinetics and removal efficiencies through IFGEM? (3) will ammonia be generated in the treatment process due to the reduction effect provided by iron filings, and, if so, how would ammonia affect the performance of IFGEM? And (4) what are the differences between raw and used  IFGEM in terms of microstructure, which might support the nutrient recovery by using spent IFGEM? We hypothesized that: (1) nitrate reduction would be significant due to the existence of iron filings as an electron donor; (2) ammonia may be produced as a byproduct from nitrate reduction; (3) phosphorus removal would be enhanced due to the precipitation of phosphate when ferrous, ferric ion, and iron oxides are more available; and (4) nutrient removal would be largely impacted by the influent nutrient concentrations.This study was conducted through three different processes Fig. , includiAn adsorption isotherm experiment was conducted separately for nitrate and phosphorus in IFGEM-1 and IFGEM-2 with deionized water under neutral pH. Five 500 mL flasks containg 30–120 g media mass were prepared with a 300 mL solution of 1.0 mg/L as total nitrate or phosphorus. The experiment was carried out under room temperature on the rotary shaker at 250 rpm for 1 hour. Then, the water sample from each flask was filtered through 0.45-µm membrane filters before the nutrient analysis. The parameters analyzed were nitrate and ammonia for the nitrate isotherm experiment, and total phosphorus for the phosphorus isotherm experiment. The Freundlich and Langmuir isotherm equations were adopted to analyze the data. The freundlich isotherm was obtained by plotting log q versus log C, and the Langmuir isotherm by plotting 1/q versus 1/C. The following two equations were applied in this study.Freundlich isotherm equation:qe is the sorbed concentration (mass of absorbed adsorbate/mass adsorbent), qm is the maximum capacity of adsorbent for adsorbate (maximum mass of absorbed adsorbate/mass adsorbent), C is the aqueous concentration of adsorbent (mass/volume), KL is the Langmuir equilibrium constant, KF is a constant indicative of the relative adsorption capacity of the adsorbent (mg1−(1/n) L1/n g−1), and n is a constant indicative of the intensity of the adsorption.Langmuir isotherm equation:Column experiments were designed to simulate the field treatment conditions with a down-flow strategy, which is critical for addressing a suite of absorption, adsorption, ion exchange, precipitation, and oxidation/reduction reactions between sorption media and nutrients that leads to determining the answers to questions 1, 2, and 3. Four column sets (named from A to D) were constructed with 10 cm (4 inches) diameter PVC pipes, and each column set was divided into three equivalent sections , and each section had a depth of 30 cm (1 foot) for convenient water sampling. As shown in Fig. 34. The columns were flushed with distilled water for a few days before starting the experiment to wash out any possible dissolvable contaminants, and were also flushed for a few hours each time before operating the columns under a different influent condition for eliminating any possible impacts from the previous influent concentrations. It was expected that physicochemical reduction/absorption would be the main mechanism for nitrate removal instead of microbiological effects, and that the only exception would be column C, which was the control column with natural soil collected from SR35 Basin 2 located in Ocala, Florida. The experiment was conducted at stable room temperature around 23 °C. A pair of peristaltic pumps with a fixed flow rate of 8 mL/min were used to pump the water from a reservoir. The pumping rate is equivalent to the infiltration rate of 1.09 cm/hr (0.43 in/hr), which was set up to mimic the drip irrigation condition using stormwater runoff or agricultural discharge. With this pumping rate, the columns were never fully saturated. The HRT and soil moisture from each section were recorded when the flow rate of the effluents could be stabilized after 3 hours of operation. Water samples were collected in triplicate from the reservoir and outlet of each section. The values of dissolved oxygen (DO), oxidation reduction potential (ORP), and pH were measured immediately after collection. IFGEM media samples were collected before and after the experiment for morphological comparison under a confocal microscope. Nitrate concentrations were analyzed through the HACH kit TN830, ammonia concentrations were analyzed through the HACH kit TN835, and total phosphorus (TP) concentrations were analyzed with the HACH Phosphorus  TNT Reagent Set  in order to simulate the fluctuation of nutrient concentrations in real stormwater runoff, agricultural discharge, or wastewater effluent from a secondary wastewater treatment plantC is the concentration of nitrate/phosphorus in solution (mg/L), n is the reaction order, and k is the reaction constant.Performance in terms of filtration kinetics refers to the efficiency of the treatment process based on the concentration from the effluent and influent . Kinetic study for nitrate reduction and phosphorus adsorption in IFGEM was conducted for the field design and BMP applications. The reaction time is recorded as hydraulic retention time (HRT) from each column section, answering question 2. Equation In a zero order reaction, the reaction rate is independent of the concentration of reactants. The reaction rate will not change when the reactants’ concentration is different per se. However, the first-order reaction is a reaction that proceeds at a rate that depends linearly on only one reactant concentration. That is, when the key reactant has a higher concentration, the reaction speed is faster than the case with a lower concentration. Second order reaction proceeds at a rate that depends non-linearly on the power of 2 of the key reactant’s concentration.3 because of the tire crumb, while the densities of IFGEM-1 and IFGEM-2 are 2.73 and 2.60 g/cm3, respectively. The soil density of 2.36 g/cm3 falls in between the density values of IFGEMs and BAM. Significant differences exist when comparing BET surface areas. Natural soil showed the highest value of 9.3712 m2/g because of aggragated clay particles, followed by IFGEM-2, with a value of 1.3963 m2/g. BAM and IFGEM-1 exhibited values of 0.7059 and 0.3142 m2/g, respectively. This is because IFGEM-1 has no micro particles, such as clay, which usually exhibits a large surface area. Another significant difference among the four media is the infiltration rate. Natural soil showed the lowest value of 0.003 cm/s, while the values of IFGEM-1, BAM, and IFGEM-2 are of the same magnitude as 0.028, 0.026, and 0.017 cm/s, respectively. The porosity differences of the four media were not as significant as the other parameters, ranging from 36.16 to 40.43% .Figure The morphological images of pre- and post-treatment IFGEM-1 and IFGEM-2 are shown in Fig. 1/qm values are negative in the Langmuir equation, it is inappropriate to apply for the calculation of the maximum absorption capacity (qm). Therefore, the Freundlich relative absorption capacity was selected from the Freundlich section in this study as the comparative basis.The isotherm study results for the phosphate adsorption of IFGEM-1 and IFGEM-2 under a neutral pH condition are shown in Fig. 1/qm values were negative in the Langmuir equation, it suggestes it is not suitable for application in the calculation of the maximum absorption capacity (qm). Consequently, the Freundlich relative absorption capacity was selected.The isotherm study results of IFGEM-1 and IFGEM-2 for nitrate reduction under a neutral pH condition, as well as the corresponding ammonia generation, are shown in Fig. The column study was designed to mimick real-world conditions. The measurements of pH, DO, and the ORP from the inlets and each sampling port of the columns are summarized in Table The cumulative nitrate removal at each sampling port of all columns is shown in Fig. The generation of ammonia from the IFGEM treatment process was confirmed as the byproduct of nitrate reduction. The ammonia concentrations from each sampling port under three different inlet nitrate concentration levels are shown in Fig. When the inlet TP = 0.3 mg/L, the overall TP removals of column A and D were 54.46% and 45.54%, respectively Fig. . When thNutrients cannot flow through the flasks during the isotherm test, but the adsorption of nutrients in the column test is a function of time, as the water flows through the column at different depths Table . In colu35 was applied to test the null hypotheses for nitrate and TP removal separately. The p values from Table The two way ANOVA analysis36 on its surface (anion attracted by the positively charged clay surface). Normally the surface of clay is negatively charged, but it can be reversed if the clay particles are modified with metal ions (ferrous and ferric ions in this study) that cover the surface of the clay and form a positively charged layer37, enhancing the clay’s anion exchange capacity. This further formed a mutual physical attraction between clay particles and iron filings that kept the clay close to the source of metal ions, enhancing the nitrate reduction process through direct contact with iron  exhibited promising removal efficiencies at various influent nutrient concentrations when iron functioned as an electron donor. However, IFGEM-2 was more effective for nitrate removal when compared with IFGEM-1. IFGEM-2 was able to remove all the nitrate at the top section, but IFGEM-1 required using all three sections to achieve equivalent treatment  happened mainly at the top section 2 Eqs.  and 641.42.Also, based on the isotherm study result Fig. , IFGEM-2From the mophological analysis result shown in Fig. It has historically been difficult to control nonpoint source contamination originating from stormwater runoff and agricultural effluent. As this contamination negatively affects both sources of drinking water and agricultural production, its unfettered continuation amounts to a significant threat to the food security of the world. Hence, two IFGEM recipes were invented and evaluated in parallel for their nutrient removal performance in comparison against traditional green sorption media (BAM) and natural soil collected from a study site in Ocala, Florida. Both IFGEM recipes showed excellent nitrate reduction due to the existence of iron filings as the reactive electron donor, but the mix of IFGEM-1 was less capable of removing ammonia (byproduct), while the mix of IFGEM-2 was able to remove most generated ammonia. The phosphorus removal was enhanced by the nitrate reduction in two IFGEM-only columns, given that the iron oxides produced from iron filings can bond with phosphorus for precipitation; however, IFGEM-1 showed superior and more stable phosphorus removal than IFGEM-2 because the ferrous/ferric ions were dissolved in the solution rather than aggregated on the clay surface, and the ORP decrement in IFGEM-1 was not as influential as that in IFGEM-2.Overall, it is indictive that spent IFGEMs could be candidate media mixes for nutrient recovery/reuse when ammonia and phosphorus are kept within IFGEM mixes under various changing influent conditions. The mix of IFGEM-1 is preferred for treatments for higher phosphorus removal, albeit lower ammonia removal and recovery. The mix of IFGEM-2 is appropriate for treating stormwater runoff, agricultural discharge, and wastewater effluents with the simultaneous removal of phosphorus and nitrate, albeit with lower phosphorus removal. Nevertheless, both IFGEM recipes showed possible nutrient recovery potential as soil amendment through different landscape environments. Future work may be directed to assess the treatability of IFGEMs under various temperature and pH conditions to ensure that IFGEMs can be applied in different scenarios with quantitative information regarding the amount of nutrients that can be recovered from spent IFGEMs.Supplementary information.


DSC and FT-IR studies showed that glimepiride does not undergo polymorphic transformations during processing, and that the milling process induces changes in the hydrogen bonding patterns of glimepiride crystals. Lattice energy framework and topology analysis revealed the existence of a possible slip plane on the (101) surface, which was experimentally verified by PXRD analysis. Dissolution testing proved the superior performance of nanocrystals, and emphasized the important influence of the stabilizer on the dissolution rate of the nanocrystals.Nanocrystal formation for the dissolution enhancement of glimepiride was attempted by wet media milling. Different stabilizers were tested and the obtained nanosuspensions were solidified by spray drying in presence of mannitol, and characterized regarding their redispersibility by dynamic light scattering, physicochemical properties by differential scanning calorimetry (DSC), FT-IR spectroscopy, powder X-ray diffraction (PXRD), and scanning electron microcopy (SEM), as well as dissolution rate. Lattice energy frameworks combined with topology analysis were used in order to gain insight into the mechanisms of particle fracture. It was found that nanosuspensions with narrow size distribution can be obtained in presence of poloxamer 188, HPC-SL and Pharmacoat The oral route of administration is considered as the first choice for drug administration due to its convenience, non-invasiveness, good patient compliance and the lowest cost of therapy. However, absorption of drug after oral delivery can be significantly hindered if the drug is poorly soluble in the gastrointestinal fluids, since drug dissolution is necessary prerequisite for its absorption into systemic circulation. It is estimated that about 70% of newly synthesized drugs are poorly soluble in the aqueous fluids and this number steadily increases . Increas6 cm/s), glimepiride is classified in the class II of the Biopharmaceutics Classification System (BCS) [Among the drugs whose poor water solubility is a limiting factor to their bioavailability and therapeutic efficacy, and which are expected to benefit from a nanocrystal-based formulation, the antidiabetics of the sulfonylurea class hold a prominent position. Therefore, in the present study, glimepiride, a third-generation sulfonylurea oral hypoglycemic agent used for the treatment of patients with type II non-insulin-dependent diabetes mellitus , was selem (BCS) , showingem (BCS) ,16. Howeem (BCS) . Numerouem (BCS) , self-emem (BCS) , complexem (BCS) , microniem (BCS) , solid dem (BCS) ,21,22,23em (BCS) .Although there are several reports regarding the use of nanosuspensions for improving solubility and bioavailability of glimepiride ,26, in t® 603 and Pharmacoat® 615 , differing in viscosity, poloxamer 188 , polyvinylpyrrolidone K25  and polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer  were tested as potential nanosuspension stabilizers. Mannitol  was used as a matrix former for spray drying of the nanosuspension in order to prevent aggregation of glimepiride nanocrystals during solidification process.Glimepiride  were placed in 45 mL milling bowl loaded with 70 g of zirconium oxide milling beads (0.1 mm diameter). After addition 6 mL of water, milling was performed at 450 rpm mill rotation speed in 20 cycles of 3 min with 5 min breaks after each milling cycle to prevent instrumentation and sample overheating.Glimepiride nanocrystal suspensions were prepared employing the wet media milling technique on a planetary ball mill . Glimepiride (0.5 g) and one of the tested stabilizers (25% The zeta average (z-average) size and polydispersity index (PDI) of glimepiride nanoparticles were monitored during the milling process by dynamic light scattering using a Zetasizer nano ZS instrument . At predetermined time intervals , samples were withdrawn from the milling bowl, for the monitoring of particle comminution kinetics as a function of time. Each measurement was repeated in triplicate. Particle size determination was performed after a week’s storage in a refrigerator (5 ± 3 °C), in order to evaluate the short term stability of the nanoparticles.3/h, inlet air temperature 80 °C (70 °C for formulation with poloxamer 188), aspirator 100% and pump speed of 5%. Spray dried samples were stored in a desiccator over phosphorus pentoxide until further analysis. Additionally, for comparison purposes, physical mixtures of glimepiride with mannitol and each stabilizer at the same mass ratio used in the milling experiments were prepared by manual mixing for 5 min, with mortar and pestle.After selection of appropriate stabilizers, nanosuspensions were diluted with aqueous solution of mannitol (glimepiride:mannitol mass ratio 1:5) and spray dried using a Büchi B-191 Mini Spray-dryer  with the following process parameters: air flow rate 800 mD0 is the initial z-average diameter of the nanocrystals (before solidification), and D is the z-average diameter of the redispersed nanosuspension. RDI values close to 1 indicate that the nanosuspension can recover its original particle size after immersion to the aqueous medium.Redispersibility testing was performed in order to investigate the ability of reconstitution of glimepiride nanosuspension upon contact of solidified material with water. Approximately 2–3 mg of dried nanosuspension were immersed in 4 mL of distilled water and subjected to ultra-sonication for 3 min. The z-average diameter of the redispersed nanosuspensions was determined on a Zetasizer nano ZS particle size analyzer , as previously described, and the Redispersibility Index (RDI) was calculated according to Equation (1) :(1)RDIAccurately weighted 5–10 mg of samples were placed in perforated aluminium pans, and DSC scans were performed in the range of 25–250 °C at a heating rate of 10 °C/min, using a DSC 204 F1 Phoenix heat-flux differential scanning calorimeter . Nitrogen gas flow (70 mL/min) was applied, and an empty pan was used as reference.−1 at 4 cm−1 resolution were recorded using a horizontal Golden-Gate MKII single-reflection ATR accessory  equipped with ZnSe lenses, mounted on a Shimadzu IR-Prestige-21 FT-IR spectrometer . A total number of 32 scans was averaged per spectrum.FT-IR spectroscopy was used in order to detect the presence of intermolecular interactions between components of nanosuspensions. FT-IR spectra in the range of 600–4000 cmθ range in 0.05° steps at a scan rate of 12 s per step, employing a Bruker D8 Advance diffractometer  equipped with a Johanson type Ge-crystal primary monochromator producing CuKα1 radiation (λ = 1. 541 Å).Powder X-ray diffractometry (PXRD) scans were performed within the 3–40° 2Nanocrystal samples were coated with a carbon later and SEM photomicrographs were acquired on a JSM 840A scanning electron microscope .Dissolution testing of glimepiride from the samples of pure drug and spray dried nanosuspensions was performed using rotating paddle apparatus during 3 h in 500 mL of phosphate buffer pH = 7.8, as recommended by FDA, with paddle rotation speed of 50 rpm. Sample mass equivalent to 6 mg of glimepiride was used for testing. At predetermined time intervals  aliquots of 4 mL were withdrawn from the dissolution vessel, filtered through 0.1 μm membrane filter and the amount of dissolved glimepiride was determined spectrophotometrically at 226 nm. All analyses were performed in triplicate and results are expressed as mean ± standard deviation (SD).In order to enhance our understanding of glimepiride’s mechanical properties relevant to particle fracture during milling, the crystal properties of the commercially available polymorph I were modelled by a combination of quantum and molecular mechanics methods. The crystal structure of glimepiride polymorph I was retrieved from the Cambridge Structural Database (CSD reference code TOHBUN01) and all X–H bond lengths were normalized according to neutron diffraction data (C–H 1.083 Å and N–H 1.009 Å). Subsequently, various lattice properties and crystal morphology was calculated as follows:The total energy of the interactions of the basic molecule with its environment in the crystal was determined following the procedure described in the reference . The firIn order to understand how the lattice energy framework affects the crystals’ mechanical properties at the macroscopic level, the crystal morphology of glimepiride form I based on the surface attachment energy (SAE) theory, was calculated using the Oscail/Ritnos software program (Version 4.2) , using L® 603 and Pharmacoat® 615 were used as stabilizing agents. Measured particle size after 60 min of milling for these mixtures was in the range between 182.3 ± 11.8 and 397.7 ± 8.3 nm, while PDI for these experimental runs was below 0.3 . This is a consequence of viscous dampening effect where energy is dissipated by the displacement of the highly viscous phase, reducing the amount of energy which is transferred from the milling beads to the suspended particles [® and Pharmacoat® 603, were selected for further studies.These results proved that wet media milling using poloxamer 188, HPC-SL, HPC-L, Pharmacoatarticles . This rearticles . Therefo® was used as a stabilizer, the size of glimepiride crystals remained high and increased during the whole milling process, indicating particle aggregation and/or recrystallization. Particle growth in nanosuspensions can occur due to Ostwald ripening phenomenon where larger particles grow at the expense of dissolution of fine particles, which are more unstable in the suspending media due to their higher surface energy [® were used as stabilizers, so these two polymers were excluded from further studies.Wet media milling process with PVP K25 resulted in initial particle size reduction during the first three cycles of milling (9 min), after which particle size increased until the end of the milling process b. When Se energy . This sue energy . Ostwald® in the refrigerator, so the aforementioned nanosuspensions can be considered as sufficiently stable for industrial processing. The particle size reduction observed during storage of samples with Soluplus® could be a result of further particle growth and consequent precipitation of excessively large particles, which can no longer remain dispersed and sampled for redispersibility testing. Based on the results of wet media milling experiments, nanosuspensions stabilized with HPC-SL (sample F1), poloxamer 188 (F2) and Pharmacoat® 603 (F3) were selected for spray drying and further characterization.Since the prepared nanosuspensions were intended for further solidification after milling process, long term stability of liquid nanosuspensions was not required and therefore not tested. However, short-term stability after storage in the refrigerator was tested to show sensitivity of nanosuspensions to short storage periods between milling and solidification. Stability testing proved that initial particle size and polydispersity index remain almost unchanged after 7-day storage of nanosuspensions prepared with HPC, poloxamer 188, and Pharmacoat® 603 (RDI = 1.04) releases initial nanoparticles after contact with aqueous media. Although the use of poloxamer 188 as a stabilizer resulted in the lowest size of glimepiride crystals after wet media milling process, the solidified sample of this nanosuspension failed to recover the initial nanoparticles (RDI = 0.53). The measured size of glimepiride nanoparticles after redispersion of this sample was around twice as large compared to nanosuspension before solidification. Since poloxamer 188 melts at low temperatures (~50 °C), agglomeration of particles occurs during spray drying in the stream of hot air, which was later proved by SEM analysis , aggregation and solid state transformation, solidification techniques are employed in order to develop stable dosage forms, suitable for commercial application . Solidifanalysis .−1 (ureidic N-H stretching vibrations), 1703 cm−1 (stretching vibrations of ureidic C=O group), 1670 cm−1 (stretching vibrations of amide C=O group), 1541 cm−1 (amide N–H bending vibrations), 1344 and 1151 cm−1 , which is in accordance with the spectra previously described in the literature for polymorph I of glimepiride [−1 in the spectra of pure glimepiride and physical mixtures, only a single broad band positioned between 3280 and 3180 cm−1 was observed in the spectra of spray dried nanosuspensions.mepiride ,44,45. SThe observed changes of the shape and intensity of these absorption bands indicates some changes in the intermolecular interactions between glimepiride molecules, which can be induced by mechanical stress in the milling process. Significantly lower intensity in the IR absorption bands of glimepiride in the spectra of spray dried nanosuspensions, compared to those of corresponding physical mixtures gives further evidence of changes in the pattern of intermolecular interactions between glimepiride molecules in spray dried nanosuspensions. Glimepiride contains three hydrogen bond donors and seven hydrogen bond acceptors and it has been previously shown that glimepiride forms three intramolecular hydrogen bonds , while iDSC thermograms of raw materials, spray dried nanosuspensions and corresponding physical mixtures are shown in All polymers used as stabilizers of nanosuspensions showed only broad endothermic events in the DSC curves, which are characteristic for amorphous materials (data not shown). The melting peak of glimepiride was observed in all samples of the spray dried nanosuspensions, confirming the presence of crystalline glimepiride. A significant shift of glimepiride’s melting peak from 214.4 °C to 187.6–188.4 °C was observed in the thermograms of spray dried nanosuspensions. It is well known that melting point depression occurs with reduction in the size of crystals, as described by the Gibbs–Thomson equation . Additioθ, which correspond to those previously reported for the stable polymorph I of glimepiride [PXRD analysis, mepiride ,48.θ, which is very low in the diffractogram of pure glimepiride, significantly increased in intensity and became clearly pronounced in the diffractograms of all spray dried nanosuspensions. Changes of surface properties and crystal morphology due to the milling process have been previously documented for propranolol hydrochloride and paracetamol [θ reflection corresponds to the (101) Miller plane. In order to elucidate the mechanism causing the increased expression of this particular Miller plane, the energy framework of the crystal lattice of glimepiride polymorph I, along with the crystal morphology model is discussed below.All characteristic glimepiride peaks retained their positions in the diffractograms of spray dried nanosuspensions, indicating absence of polymorphic transitions during milling and spray drying. However, the peak positioned at 9.75° 2acetamol ,50. It iacetamol . The chaIn an attempt to bridge the gap between macroscopic mechanical properties and crystal structure and lattice energetics, energy frameworks combined with topology analysis  were useEinter = −21.5 kcal/mol), followed by hydrogen bonded dimers . Inspection of the EVD plots alone reveals the existence of a slip direction along the (101) crystal plane, leading to the misconception that this could be a preferred slip plane that could facilitate plastic flow. A more detailed observation of the crystal lattice topology clearly shows that the (101) plane intersects with the intermolecular hydrogen bonds of dimer 11, therefore slip along that plane would require a substantial amount of energy in order to disrupt the hydrogen bonded dimers of glimepiride, rendering deformation by plastic flow rather unlikely, in favor of brittle fracture. Therefore, considering the spatial distribution of intermolecular forces depicted in the EVD plots, combined with topology analysis, it is expected that brittle fracture along the (101) crystal plane should occur upon the application of mechanical stress. This is in agreement with the PXRD findings that the (101) reflection overexpressed after milling, and it can be explained on the basis of preferred breakage of the particles along that plane.It is seen that the strongest stabilizing interactions  theory, which is shown in ®), and from those who lack hydrogen bond donors, only for poloxamer, whose ether oxygens are more accessible by the surface molecules of glimepiride, due to the absence of “bulky” substituents (such as rings) in poloxamer’s structure. For the other two polymers that lack hydrogen bond donor groups, namely PVP K25 and Soluplus®, the presence of bulky substituents and the complex branched structure seem to limit their ability to act as stabilizers, as has been evidenced by the increasing particle size of the nanocrystals during milling  plane constitutes only a small part of the overall crystal surface area, which is in agreement with the X-ray diffractogram of the raw (unmilled) material. The surface chemistry of the (101) slip plane, illustrated in  milling b.Moreover, the formation of hydrogen bonds between glimepiride and stabilizers on the overexpressed (101) face could explain the observed milling-induced changes in the FTIR absorption bands discussed above.® 603 showed characteristic wrinkled-surface sphere morphology. During spray drying of droplets, spherical particles are initially forming a thin solid coat during drying of the droplet surface, under which the liquid droplet interior is still preserved. Progression of drying process causes elevation of pressure within the sphere due to water evaporation from interior droplet, which leads to the collapse of the sphere and formation of particles with hollow surfaces [Scanning electron micrographs of spray dried nanosuspensions are shown on surfaces . SphericDissolution profiles of pure glimepiride and spray dried nanosuspensions are shown in Pure glimepiride showed very slow and incomplete dissolution with less than 30% of dissolved amount during 3 h of testing. This behavior of pure glimepiride is expected as it is practically insoluble within the physiological pH range, with a reported solubility of 0.0012 mg/mL in aqueous media with pH 7.0, and 0.00087 mg/mL in pH 6.8 . GlimepiProduction of nanocrystals of glimepiride with a uniform particle size distribution is feasible by wet media milling, with the aid of poloxamer 188 and low viscosity grades of HPC and HPMC polymers. Wet media milling proved advantageous technique for production glimepiride nanosuspension in that it does not induce polymorphic transformations, preserving the stable polymorph of glimepiride. Spray drying is an efficient solidification method, which stabilizes the nanocrystals and ensures redispersibility when appropriate stabilizers are used. Lattice energy framework combined with topology analysis and crystal morphology modeling can provide significant insight into the mechanisms of particle fracture and provide explanations for otherwise difficult to understand experimental findings. Finally, dissolution testing proved the enhanced dissolution of nanocrystals, and additionally revealed the fact that redispersibility alone is not a good predictor of dissolution rate, but the stabilizers’ intrinsic properties should always be taken under consideration.