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Carbohydrate partitioning is essential for plant growth and development, and its hindrance will result in excess accumulation of carbohydrates in source tissues. Most of the related mutants in maize (Zea mays L.) display impaired whole‐plant sucrose transport, but other mechanisms affecting carbohydrate partitioning have seldom been reported. Here, we characterized chlorotic leaf3 (chl3), a recessive mutation causing leaf chlorosis with starch accumulation excessively in bundle sheath chloroplasts, suggesting that chl3 is defective in carbohydrate partitioning. Positional cloning revealed that the chl3 phenotype results from a frameshift mutation in ZmPHOH, which encodes starch phosphorylase 2. Two mutants in ZmPHOH exhibited the same phenotype as chl3, and both alleles failed to complement the chl3 mutant phenotype in an allelism test. Inactivation of ZmPHOH in chl3 leaves reduced the efficiency of transitory starch conversion, resulting in increased leaf starch contents and altered carbohydrate metabolism patterns. RNA‐seq revealed the transcriptional downregulation of genes related to photosynthesis and carbohydrate metabolism in chl3 leaves compared to the wild type. Our results demonstrate that transitory starch remobilization is very important for cellular carbohydrate partitioning in maize, in which ZmPHOH plays an indispensable role. [ABSTRACT FROM AUTHOR]

A facile photo-irradiation method is developed to tune active sites over β-Ni(OH)2 nanosheets. Photo-irradiated β-Ni(OH)2 nanosheets possess disordered surface atoms and preferred growth of highly active crystal facets, which exhibit enhanced performance for the electrocatalytic oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

The electronic structure of catalysts influences the electrocatalytic behavior. Herein, the electronic structure of NiO nanocrystals is modified by doping with a small amount of Li+. The Li+ doped NiO nanocrystals show much better OER activity than pristine NiO and LiNiO2, which is a result of tuned Fermi levels, stronger hybridization between Ni 3d and O 2p, and narrowed energy band gap. This work provides a facile strategy to regulate NiO electronic energy bands to promote OER performance. [ABSTRACT FROM AUTHOR]

In this study, MIL-101(Fe) is prepared via a facile solvent-thermal method, and then applied as catalyst for activating PMS, thus generating reactive radicals for organic dyes removal in aqueous solution. Rhodamine B (RhB), Malachite Green (MG) and Methylene Blue (MB) were selected as model pollutants. The experiments showed that MIL-101(Fe)/PMS had higher removal efficiency for dyes than MIL-101(Fe), indicating that MIL-101(Fe) can be simultaneously used as adsorbent and PMS-activating catalyst for dyes removal. The effects of initial pH and the coexisted negative ions on MB degradation were further discussed, showing that MIL-101(Fe) can degrade MB with excellent stability. Furthermore, the reactive species in MIL-101(Fe)/PMS system were deduced as sulfate radicals and hydroxyl radicals. Finally, the degradation intermediates and possible degradation pathway were investigated by LC-MS. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Simulated irrigation experiment was built up to study As behavior in the unsaturated zone. • The mobilization of As is closely related to the water table fluctuation. • Change of redox condition due to periodic irrigation controls As mobilization. Abstract High level of arsenic-containing groundwater has been used for irrigation purposes for several decades in Asia, leading to fluctuating water table and redox conditions in the unsaturated zone, thereby potentially affecting the mobilization of arsenic in the unsaturated and saturated zones. A field plot experiment was conducted in the arsenic – affected area of the Datong Basin, China to determine the effects of irrigation return flow on the hydrogeochemical behavior of arsenic and iron in the unsaturated zone. High-arsenic groundwater was extracted from a shallow aquifer far from the irrigation site and used as irrigation water. Soil water/shallow groundwater and soil/sediment samples were collected at different depths from the field site during the experiment. Water samples were analyzed to determine hydrochemical properties and arsenic concentrations, and soil/sediment samples were analyzed to determine total iron and arsenic. Infiltration of irrigation water into the unsaturated zone led to fluctuations in the water table, varying redox conditions, and the redistribution of arsenic and iron in the near-surface soil/sediment. Soil/sediment bulk geochemical analysis results indicate obvious increases of arsenic and iron in topsoil after irrigation. Infiltration of irrigation water carrying organic matter, sulfate, and nitrate into the subsurface affects the (bio)geochemistry of the unsaturated and saturated zones, and ultimately the behavior of arsenic and iron. Geochemical modeling results suggest desorption and leaching processes are responsible for the temporal changes of arsenic concentrations in both pore water, groundwater and sediment during irrigation. The results of this study indicate that flood irrigation using arsenic-contaminated groundwater should be controlled and gradually replaced by drip irrigation, sprinkler irrigation or irrigation using non-contaminated water resources to mitigate arsenic accumulation in the unsaturated zone and shallow groundwater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co doped MIL-101(Fe, Co) with different degrees was synthesized by a simplified benign method. • MIL-101(Fe, Co) presented higher activity than MIL-101(Fe) for peroxymonsulfate(PMS) activation. • MIL-101(Fe, Co)/PMS exhibited excellent degradation performance for organic dyes. • MIL-101(Fe, Co 20%) have good structural stability and recyclability.. In order to further improve the catalytic performance of MIL-101, cobalt-doped MIL-101(Fe,Co) was synthesized by solvothermal method. By adjusting the ratio of cobalt doping, the MIL-101(Fe,Co 20%) with the best catalytic activity was obtained. The activation performance of MIL-101(Fe,Co 20%) for peroxymonosulfate (PMS) was studied using Rhodamine B (RhB) as a pollutant model. The experimental results proved MIL-101(Fe,Co 20%) with much better catalytic performance than MIL-101(Fe), which can degrade more than 99% of RhB within 15 min. The effects of initial solution pH and coexisting anions in water on the degradation of RhB were further discussed. The results showed that MIL-101(Fe,Co 20%) was with excellent stability and degradation efficiency can still keep above 90% after five cycles. The free radical quenching experiments were further studied to explore the degradation mechanism. It can be concluded that SO 4 -· was the main active free radical for the degradation of RhB. The possible intermediate products in the degradation process of RhB were analyzed by LC-MS. Combined with the comparison of XPS before and after the reaction, the possible reaction mechanism of RhB degradation process was inferred. [ABSTRACT FROM AUTHOR]

• Interactions among As, Fe, and OM under different irrigation scenarios were extended. • The inhibition of As adsorption on ferrihydrite occurs in the presence of OM. • As–Fe–OM complexes and OM influence As desorption during irrigation. Arsenic (As)–iron (Fe)–organic matter (OM) compound is critical for the mobilization of As under irrigation conditions. We explore the interaction mechanism among As–Fe–OM components for different reaction pathways in column experiments under irrigation conditions using ferrihydrite-coated sand, sodium humate (HA), and As(III). Arsenic mobilization is strongly controlled by the adsorption of As on Fe minerals, which in turn is affected by the presence of OM. In the pure ferrihydrite-coated sand column, outlet As and HA concentrations gradually increased and reached a stable state. In the ferrihydrite-As-coated sand columns, the release of As occurred with HA infiltration and the HA concentrations influenced the release rate of As from the ferrihydrite. The results suggest OM interacts with As and Fe minerals to promote As mobility, with the concentration OM influencing the amount of As released. Although competitive adsorption occurred in the presence of OM, ferrihydrite acts as bridges between As and OM to form As–Fe–OM ternary complexes and further affected the mobilization of As. These results are important for evaluating the migration of As under agricultural activities using high-As groundwater for irrigation and indicate managing OM and As-contaminated water for agricultural activities is required to limit impacts on human health. [ABSTRACT FROM AUTHOR]

• Representative cities regrouped for energy-saving potentials upon STPV integration. • Coupled STPV integration scenario induced energy-saving effects got validated. • Energy-saving effects of STPV photo-thermal-electrical property variations examined. • Design strategies for both integration concerns got proposed accordingly. Semi-Transparent Photovoltaics (STPVs) have received increasing popularities as they conform to the architectural design trend of large-area glass curtain walls and expand the application scenes of building integrated photovoltaics (BIPVs). However, their high sensitivities toward extreme thermal and radiation climate conditions as well as the potential key integration scenario--skylights for large footprint buildings, have rarely been highlighted. Meanwhile, in context of the low energy glass application consensus as well as varieties of commercial module typologies with diverse photo-thermal-electrical properties, designers are still in lack of key understandings regarding actual energy performances and appropriate design solutions of STPV integrations upon diversed climate conditions. In this work, the actual energy-saving disparities, occasioned by distinct climate conditions of both thermal design and solar radiation resources, have been investigated in detail through simulation validations over representative large footprint railway station building prototypes. 14 representative cities covering most concerning climate zones, as well as seven STPV modules based on different PV technologies or featured photo-thermal-electrical properties had been examined for their climate responsivenesses. All engaged cities have been re-grouped from the new perspective into four categories (Low, Medium, High, Ultra-high energy-saving beneficial) with corresponding energy-saving rates (ESRs) (<15%, 14%∼20%, 20%∼22%, >24%) to reveal their true energy-saving beneficial potential levels. Design strategies on basis of applicable integration scenarios as well as appropriate module properties and typologies have been proposed corresponding to each reclassified city categories, to achieve the best conjugated energy-saving effects. This research can provide essential knowledge for finalizing STPV integration designs under the premise of a best energy-saving performance, in response to diversified and complicated climate conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mobilization of As is closely related to Fe minerals and OM during irrigation. • OM introduced by the irrigation affected As and Fe behavior. • Ternary complexation of As-Fe-OM compounds influence As mobilization during irrigation. • Terrestrial OM promotes As-Fe-OM complexation reactions during irrigation. Organic matter (OM) plays an important role in the biogeochemical transformation of arsenic (As) in groundwater and sediments. High-As groundwater used for irrigation introduces dissolved As into the ground. Moreover, water table fluctuations and variations in redox conditions affect As mobilization in both the unsaturated and saturated zones. A field experiment was conducted at the DY site, Datong Basin, China to explore the effect of OM on As and iron (Fe) mobilization and transformation in the unsaturated and saturated zones during irrigation. Soil water/groundwater and sediments sampled at different depths during the experiment were analyzed to investigate the hydrochemical processes and correlations between As, Fe, and OM concentrations. Irrigation activities led to the accumulation of aqueous As in the saturated zone and increasing As content in the topsoil. Analyses of Fourier-transform infrared (FTIR) spectra suggest the existence of As-Fe-OM ternary complexation. Parallel factor analysis (PARAFAC) of the three-dimensional fluorescence excitation–emission matrix (EEM) reveals that water-extractable organic matter (WEOM) of sediments comprises three major components, two terrestrial humic-like components (C1 and C2) and one protein-like component (C3). And terrestrial humic-like components with high molecular weight promotes As-Fe-OM complexation reactions. The results of this study demonstrate As mobilization under irrigation conditions and contribute to a better understanding of the role of OM under high-As groundwater irrigation. This study has implications for controlling and managing OM or As-contaminated water for irrigation in high-As groundwater regions. [ABSTRACT FROM AUTHOR]

Coal burst has become one of the most serious hazards in longwall coal mines of many countries, and extensive studies have been conducted on the mechanism, prediction, and prevention of coal bursts. However, most of these studies focus on qualitative descriptions of burst environments and specific case analyses. Few studies have been carried out to explore knowledge through a number of past coal bursts in longwall mines. The main objective is to quantitatively analyze the current burst‐prone conditions in longwall coal mines of China and to summarize corresponding lessons. A database consisting of 54 major coal bursts was established. The characteristics and contributing factors of involved coal bursts were analyzed quantitatively, and high‐risk areas that are common in coal mines were then identified. Finally, some suggestions and lessons were proposed. This study may help for identifying controlling factors and high‐risk areas at a specific mine, and it might provide insights into the control of coal bursts in longwall coal mines. [ABSTRACT FROM AUTHOR]

Background: Oligoasthenoteratozoospermia (OAT) is one of the most complex aggregators of male gametic problems. However, the genetic etiology of OAT is still largely unknown. Objectives: To reveal the new genetic factors responsible for male infertility owning to OAT and reveal the outcomes of the affected patients from intracytoplasmic sperm injection (ICSI). Materials and methods: Two infertile men with typical OAT were recruited in 2018 and retrospected a cohort that included 47 patients with OAT from 2013 to 2021. Fifty healthy men with proven fertility served as control subjects. To identify the novel pathogenic variants, whole‐exome sequencing and Sanger sequencing were used. In silico analysis revealed the affecting of the variants. Field emission scanning electron microscopy was employed to observe the morphological defects of the spermatozoa. Immunofluorescence was used to analyze the expression and localization of the related protein. CRISPR/Cas9 was used to generate the mouse model. ICSI was used as a treatment for the patients and to assess the effects of the pathogenic variant on fertilization and embryo development. Results: We identified a loss‐of‐function mutation NM_001170574.2:c.823G > T (p.Glu275*) in X‐linked TENT5D from two patients with OAT. This variant is highly deleterious and has not been found in the human population. The count of patients' spermatozoa is dramatically decreased and displays multiple morphologic abnormalities with poor motility. Tent5d knockout mice are infertile and exhibit parallel defects. ICSI could rescue the infertility of the Tent5d knockout male mice. Moreover, the proband was treated with ICSI and achieved a successful pregnancy outcome for the first time. Subsequent mutation screening identified no TENT5D mutations among 47 additional patients with OAT and 50 control subjects. Conclusion: Mutation in TENT5D results in OAT and male infertility, and this terrible situation could be rescued by ICSI. [ABSTRACT FROM AUTHOR]

Groundwater serves as a vital source of drinking water in the Hetao Basin of northwestern China. However, the occurrence and intense spatial variability of high fluoride (F−>1.5 mg/L) groundwater poses a significant health threat to local residents. In this study, the Random Forest (RF) machine learning algorithm was employed to develop two prediction models for high fluoride groundwater in Qiantao and Houtao plain, northwestern China, based on 650 groundwater samples. The models incorporated hydrochemical and geospatial datasets (climatic factors, topographic factors, and soil properties) to predict the probability of fluoride in groundwater exceeding 1.5 mg/L at a 250 m spatial resolution. The results show that the high-risk areas of the Qiantao Plain and Houtao Plain cover 33.0 % and 6.7 % of the total area of the plains, respectively. The ratio of high risk (F > 1.5 mg/L) samples correctly detected in Qiantao plain and Houtao plain were 86.7% and 94.5%, indicated an increased sensitivity to high fluoride category. Hydrochemical parameters were proven to be the most effective predictors. The spatial variability of high fluoride groundwater in two plains was dominated by the lithology, tectonic evolution, and hydrogeologic settings. Hyper-parameter optimized RF models demonstrate an outstanding performance in predicting the risk of high fluoride groundwater. This research presents a cooperative and successful effort to integrate hydrochemical and geospatial variables for prediction model, which can enhance the understanding of the geological origin and anthropogenic causes, and facilitate decision-making to identify potential risks in the areas affected by high levels of fluoride in groundwater. • A high F− groundwater prediction model was developed based on RFC modelling. • Driving factors of high F− probability were evaluated and ranked. • High-risk areas of fluoride exposure were delineated in intensively irrigation area. • High fluoride groundwater prediction maps were generated with a resolution of 250 m. • Tectonic and hydrogeologic setting dominate the spatial variability of groundwater F-. [ABSTRACT FROM AUTHOR]

RNA polymerase III (RNAPIII) contains 17 subunits forming 4 functional domains that control the different stages of RNAPIII transcription and are dedicated to the synthesis of small RNAs such as 5S rRNA and tRNAs. Here, we identified 23 genes encoding these subunits in Arabidopsis (Arabidopsis thaliana) and further analyzed 5 subunits (NRPC2, NRPC3, NRPC8, NRPABC1, and NRPABC2) encoded by 6 genes with different expression patterns and belonging to different sub-complexes. The knockdown of these genes repressed the expression of 5S rRNA and tRNAs, causing seed developmental arrest at different stages. Among these knockdown mutants, RNA-seq analysis revealed 821 common differentially expressed genes (DEGs), significantly enriched in response to stress, abscisic acid, cytokinins, and the jasmonic acid signaling pathway. Weighted gene co-expression network analysis (WGCNA) revealed several hub genes involved in embryo development, carbohydrate metabolic and lipid metabolic processes. We identified numerous unique DEGs between the mutants belonging to pathways, including cell proliferation, ribosome biogenesis, cell death, and tRNA metabolic processes. Thus, NRPC2, NRPC3, NRPC8, NRPABC1, and NRPABC2 control seed development in Arabidopsis by influencing RNAPIII activity and, thus, hormone signaling. Reduced expression of these subunit genes causes an insufficient accumulation of the total RNAPIII, leading to the phenotypes observed following the genetic knockdown of these subunits. [ABSTRACT FROM AUTHOR]

• Zmsmk9 mutants delay endosperm and embryo development at the early stages. • Zmsmk9 mutants develop into natural plants with upright leaf architecture. • ZmSMK9 encodes a pentatricopeptide repeat protein targeted to mitochondria. • ZmSMK9 is involved in the splicing of nad5 intron-1 and intron-4. Maize kernel size and weight are essential contributors to its yield. So the identification of the genes controlling kernel size and weight can give us a chance to gain the yield. Here, we identified a small kernel mutant, Zea mays small kernel 9 (Zmsmk9) , in maize. Cytological observation showed that the development of the endosperm and embryo was delayed in Zmsmk9 mutants at the early stages, resulting in a small kernel phenotype. Interestingly, despite substantial variation in kernel size, the germination of Zmsmk9 seeds was comparable to that of WT, and could develop into normal plants with upright leaf architecture. We cloned Zmsmk9 via map-based cloning. ZmSMK9 encodes a P-type pentatricopeptide repeat protein that targets to mitochondria, and is involved in RNA splicing in mitochondrial NADH dehydrogenase5 (nad5) intron-1 and intron-4. Consistent with the delayed development phenotype, transcriptome analysis of 12-DAP endosperm showed that starch and zeins biosynthesis related genes were dramatically down regulated in Zmsmk9, while cell cycle and cell growth related genes were dramatically increased. As a result, ZmSMK9 is a novel gene required for the splicing of nad5 intron-1 and intron-4, kernel development, and plant architecture in maize. [ABSTRACT FROM AUTHOR]

A novel method for subpixel mapping of urban built-up areas (SMUBA) using spatial-spectral information from satellite multispectral remote sensing imagery is proposed. SMUBA contains two terms, a spatial term and a spectral term. First, a spatial attraction model is used to produce the spatial term. The Normalized difference built-up index is then utilized to obtain the spectral term. Finally, a particle swarm optimization algorithm is used to optimize the two terms and obtain the final mapping result. Since the spatial-spectral information of the urban built-up areas from multispectral imagery is fully utilized by the two terms, the final mapping result is improved. Experimental results on two Landsat 8 Operational Land Imager data show that SMUBA produces better mapping results than state-of-the-art subpixel mapping methods. Moreover, the proposed method does not need any prior shape information. [ABSTRACT FROM AUTHOR]

Background and Objectives: This study explored the prevalence of gestational diabetes mellitus (GDM) in Chinese pregnant women and identified risk factors for GDM after the implementation of the universal two-child policy.Methods and Study Design: On the basis of income and population, we randomly selected three hospitals through stratified and cluster sampling. From January 1 to July 31, 2016, 4959 women who had been registered within 12 weeks of gestation received a 75-g 2-h oral glucose tolerance test (OGTT) at 24-28 gestational weeks. International Association of Diabetes and Pregnancy Study Group criteria were used for the diagnosis of GDM.Results: The OGTT was positive in 1080 (21.8%; 1080/4959) women, who were then diagnosed as having GDM on the basis of their results. GDM was positively associated with the following factors: advanced maternal age (p<0.001; adjusted odds ratio [OR]=4.88; 95% confidence interval [CI]=2.38-10.0, pre-pregnancy body mass index overweight (OR=2.44, 95% CI=1.78-3.34)/obesity (OR=10.9, 95% CI=6-19.6; p<0.001), paternal history of diabetes (p=0.003; OR=2.54, 95% CI=1.38-4.67), and maternal history of diabetes (p<0.001; OR=3.6, 95% CI=2.16-5.98).Conclusions: Qingdao has an exceptionally high estimated prevalence of GDM. Widely recognized risk factors for GDM were advanced age, pre-pregnancy overweight/obesity, and a family history of diabetes in first-degree relatives. More options to prevent and manage GDM must be explored. [ABSTRACT FROM AUTHOR]