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Grazing is one of the most important management practices for grasslands. To date, most studies on how grazing affects plant diseases have focused on a single plant species, ignoring plant community characteristics and phylogeny. We used data from a 6-year yak grazing experiment (0, 1, 2, and 3 yak(s) ha

The rapid biodiversity losses of the Anthropocene have motivated ecologists to understand how biodiversity affects infectious diseases. Spatial scale is thought to moderate negative biodiversity-disease relationships (i.e., dilution effects) in zoonotic diseases, while evidence from plant communities for an effect of scale remains limited, especially at local scales where the mechanisms (e.g., encounter reduction) underlying dilution effects actually work. Here, we tested how spatial scale affects the direction and magnitude of biodiversity-disease relationships. We utilized a ten-year-old nitrogen addition experiment in a Tibetan alpine meadow, with 0, 5, 10, and 15 g/m

Plant pathogens and their hosts often coexist with mammal grazers. However, the direction and strength of grazing effects on foliar fungal diseases can be idiosyncratic, varying among host plant species and pathogen types. We combined a six-year yak grazing experiment, a clipping experiment simulating different mammal consumption patterns (leaf damage versus whole leaf removal), and a meta-analysis of 63 comparisons, to evaluate how grazing impacts foliar fungal diseases across plant growth types (grass versus forb) and pathogen life histories (biotroph versus necrotroph). In the yak grazing experiment, grazing had no significant effect on disease severity, and grasses experienced a higher disease severity than forbs; there was a significant interaction between pathogen type and grazing. In both the yak grazing experiment and meta-analysis, grazing decreased biotrophic pathogens (mainly rusts and powdery mildew), but did not affect necrotrophic pathogens (mainly leaf spots). The clipping experiment suggested that grazers might promote infection by necrotrophic pathogens by producing wounds on leaves, but inhibit biotrophic pathogens via leaf removal. In conclusion, our three-part approach revealed that intrinsic properties of both plants and pathogens shape patterns of disease in natural ecosystems, greatly improving our ability to predict disease severity under mammal grazing.

Down syndrome (DS) is the most common chromosomal condition associated with intellectual disability and is characterized by a variety of additional clinical findings. The pathogenesis of DS and the differences between the sexes are not clear. In order to identify differentially expressed proteins that might be employed as potential biological markers and elucidate the difference in pathogenesis between different genders of T21 fetuses, providing clues for individualized detection and treatment is essential. Amniocyte samples of T21 males, T21 females, CN males, and CN females were collected by amniocentesis. The quantitative value of the peptide corresponding to each sample was determined through quantitative analysis by mass spectrometry. We identified many differentially expressed proteins between T21 fetuses and CN fetuses/T21 males and CN males/T21 females and CN females/and T21 males and T21 females. These differential proteins are associated with many important biological processes and affect the development of multiple systems, including the heart, hematopoietic, immune, reproductive, and nervous systems. Our results show sex-specific modulation of protein expression and biological processes and provide new insights into sex-specific differences in the pathogenesis of DS.

The atomic structure of quasi one-dimensional (1D) van der Waals materials can be regarded as the stacking of atomic chains to form thin flakes or nanoribbons, which substantially differentiates them from typical two-dimensional (2D) layered materials and 1D nanotube/nanowire array. Here we present our studies on quasi 1D gold selenide (AuSe) that possesses highly anisotropic crystal structure, excellent electrical conductivity, giant magnetoresistance, and unusual reentrant metallic behavior. The low in-plane symmetry of AuSe gives rise to its high anisotropy of vibrational behavior. In contrast, quasi 1D AuSe exhibits high in-plane electrical conductivity along the directions of both atomic chains and perpendicular one, which can be understood as a result of strong interchain interaction. We found that AuSe exhibits a near quadratic nonsaturating giant magnetoresistance of 1841% with the magnetic field perpendicular to its in-plane. We also observe unusual reentrant metallic behavior, which is caused by the carrier mismatch in the multiband transport. Our works help to establish fundamental understandings on quasi 1D van der Waals semimetallic AuSe and identify it as a new candidate for exploring giant magnetoresistance and compensated semimetals.

Thermophilic biological nitrogen removal would be a promising alternative to conventional approaches for the treatment of high-temperature wastewater. In this study, the response of thermophilic denitrification system (50 °C) to a wide range of pH (3-11) was investigated. The results showed that thermophilic denitrification could adapt to pH 5-11, but suffered from obvious nitrite and ammonia accumulation at pH 3. Microbial insights indicated that the enrichment of specific functional thermophiles has contributed to the tolerance towards unfavorable pH. Besides, the potential selecting advantage of nitrate reducing bacteria over nitrite reducing bacteria and the enrichment of dissimilatory nitrate reduction to ammonium (DNRA) bacteria could be responsible for the nitrite and ammonia accumulation at pH 3. Moreover, the functional gene prediction denoted higher narG/(nirK + nirS) and nrfA at pH 3, which could facilitate partial denitrification and DNRA. These findings could provide new insight into the application of thermophilic biological nitrogen removal.

This study aimed to establish anaerobic biosystems which could tolerate high ammonia, and investigate the microbial community structure in these reactors. High-ammonia anaerobic biosystems that could tolerate 3600 mg L

Infertility gives rise to a lot of social and psychological problems. At present, assisted reproductive technology (ART) is an important way to solve infertility. However, the live birth rate of in vitro fertilization and embryo transfer (IVF-ET) is less than 50 %. Medium is essential for the culture of embryos in vitro. Therefore, we want to explore whether the composition of the culture medium affects the survival rate of embryos. Gentamicin (GM) is an aminoglycoside antibiotic that is used to treat various bacterial infections. It is widely used in IVF medium, but it is not known whether it has a toxicity effect on embryonic development. Here, we used zebrafish embryos to investigate the embryotoxicity of GM which is an ingredient in culture medium. Our results found that there was no significant effect on the zebrafish embryo development, including survival rate, malformation rate and developmental time course, while zebrafish embryos were treated with GM at the culture medium concentration (10 mg/L, 17.8 μM) compared with the control group. To research the potential embryotoxicity of GM, we treated zebrafish embryos with GM with high concentration (range from 17.8 μM to 3000 μM). The results showed that the lethal concentration of 50 % (LC50) at 48-h post-fertilization (hpf) value of zebrafish embryos for GM was 1150 μM; the survival rate and malformation rate of zebrafish embryos were significantly changed in a dose-dependent manner. Furthermore, transcriptomics, metabolomics and epigenomics (m6A-MeRIP-seq) were used to investigate the molecular mechanism of embryotoxicity, and results showed cell cycle, dorso-ventral axis formation and collecting duct acid secretion pathway were altered significantly in treated embryos. In conclusion, there are no adverse effects on embryonic development with the working concentration of GM in human culture medium, suggesting that GM is safe for embryo culture at working concentration.

Cystic fibrosis (CF) is associated with the manifestation of a number of medical conditions throughout the body. This prompted us to investigate the etiology of CF from the viewpoint of the embryonic organizer, which is responsible for steering the movement of surrounding cells into specific organs and tissues. In our previous work, we found that a cftr mutant had decreased nuclear β-catenin levels in the early embryo at 5 hours post-fertilization (hpf), when the organizer forms. It is known that nuclear β-catenin signaling is essential for the induction of the dorsal organizer. Therefore, we explored the role of cftr in the formation of the embryonic organizer in this work. Indeed, the expression of organizer and germ layer markers was significantly affected in cftr mutant embryos dependent on Wnt/β-catenin signaling. Furthermore, quantitative proteome analysis revealed that the cftr mutant induced significant alteration in the expression of proteins related to many critical biological processes, cellular components, molecular functions, and signaling pathways, except for the Wnt/β-catenin pathway. These findings demonstrate the function of cftr in embryonic organizer formation and provide an explanation for why many abnormalities occur in the bodies of CF patients.

Black phosphorus (BP) has been shown as a promising two‐dimensional (2D) material for electronic devices owing to its high carrier mobility. To realize complementary electronic circuits with 2D materials, it is important to fabricate both n‐type and p‐type transistors with the same channel material. By engineering the contact region with copper (Cu)‐doped BP, here we demonstrate an n‐type carrier transport in BP field‐effect transistors (FETs), which usually exhibit strongly p‐type characteristics. Cu metal atoms are found to severely penetrate into the BP flakes, which forms interstitial Cu (Cuint)‐doped edge contact and facilitates the electron transport in BP. Our BP FETs in back‐gated configuration exhibit n‐type dominant characteristics with a high electron mobility of ~ 138 cm2 V−1 s−1 at room temperature. The Schottky barrier height for electrons is relatively low because of the edge contact between Cuint‐doped BP and pristine BP channel. The contact doping of BP by highly mobile Cu atoms gives rise to n‐type transport property of BP FETs. Furthermore, we demonstrate a p‐n junction on the same BP flake with asymmetric contact. This strategy on contact engineering can be further extended to other 2D materials.

In this study, the toxic effect of high ammonia on microalgae Tetraselmis cordiformis and the detoxification of phytohormones were researched. The growth, physiological changes, and gene transcription of T. cordiformis were examined. Malondialdehyde content was increased by 2.12 times compared with the control, suggesting the oxidative damage of T. cordiformis. However, the damaging effect of ammonia stress was significantly alleviated by exogenous phytohormones revealed by photosynthetic activity, antioxidant capacity, and nitrogen metabolism. Compared with cells exposed to 500 mg L−1 ammonia (NH4+-N), phytohormones increased the transcript abundance of photosynthesis-related gene (rbcL) by up to 10.95 times. Besides, after adding phytohormones, maximum activities of the antioxidant enzyme catalase (CAT) and nitrogen metabolism-related enzyme glutamine synthetase (GS) were 2.17 and 6.72 times that of the cells exposed to 500 mg L−1 NH4+-N. This study displayed the toxic mechanism of high ammonia on T. cordiformis, and also proved the detoxification of phytohormones.

Advanced nutrient removal of municipal wastewater has insufficient carbon source, and resource recovery is neglected. In this study, a single-stage biofilter based on denitrifying phosphorus removal (DPR) was proposed for advanced nutrient removal and phosphorus recovery, which was operated under alternating anoxic/anaerobic mode with no extracellular carbon source in anoxic period. The results showed that the biofilter achieved efficient and stable performance with low carbon consumption (C/N ≈ 3.7). The average removal efficiency of NO3−-N, TN and PO43−-P were 74.81%, 71.08% and 91.15%, respectively. DPR primarily occurred in the middle of the filtration bed and nutrient removal was driven by intracellular polymers, which was the main carbon source. High-throughput sequencing indicated that Dechloromonas was enriched and contributed to DPR while Zoogloea was responsible for endogenous denitrification. Denitrifying polyphosphate accumulating organisms and endogenous denitrifiers synergistically enhanced the nutrient removal capacity. The study further provides research perspectives for improving nutrient removal.

Phosphate (PO43--P) and nitrate (NO3−-N) in the effluent of wastewater treatment plants are the predominant sources of eutrophication. In this study, a bench-scale electrochemically assisted vertical flow constructed wetland (E-VFCW) was developed, which exhibited favorable PO43--P (89.7–99.4%), NO3−-N (82.7–99.6%), and TN (51.9–93.7%) removal efficiency in tertiary wastewater treatment. In addition, little N2O accumulation (0.32–2.19% of △NO3−-N) was observed. The study further elucidated that PO43--P was removed mainly in the anode chamber by co-precipitation (Fe(n+)OH-PO4) and adsorption (FeOOH-PO4) pathways. Multi-pathway of NO3−-N reduction was proposed, with 13.9–30.2% of NO3−-N predominantly eliminated in the anode chamber by ferrous-dependent NO3−-N reduction bacteria. In the cathode chamber, electrons storage and resupply modes during S cycle exerted crucial roles in NO3−-N reduction, which enhanced the resilience capabilities of the E-VFCW to shock loadings. Stoichiometric analysis revealed that 3.3–6.6 mmol e−/cycle were stored in the form of S0, FeS, and FeS2 in the E-VFCW under longer HRT or higher current density. However, the deposited S resupplied 19.6% and 28.3% of electrons for NO3−-N reduction under shorter HRT (1 h) or lower current density (0.01 mA cm−2). Moreover, ferrous-driven NO3−-N-reducing or DNRA bacteria also promoted NO3−-N elimination in the cathode chamber. These findings provide new insight into the coupling interactions among S, Fe and H cycles, as well as N and P transformations in electrochemically assisted NO3−-N reduction systems.

Phosphorus (P) removal occurred in heterotrophic nitrification process, but its mechanism has not been fully explored. In this study, the P removal performances, pathways, and mechanisms in heterotrophic nitrification processes of different microbial aggregates (activated sludge and biofilm) were investigated. The results showed that the biofilm reactor had more efficient total nitrogen removal (98.65%) and phosphate removal (94.17%). Heterotrophic nitrification and denitrification processes generated alkalinity for biologically induced phosphate precipitation (BIPP), which contributed to 64.12%-78.81% of the overall P removal. The solid phase P content reached 48.03 mg/gSS with hydroxyapatite and calcium phosphate formation. The study clarified that biofilm was beneficial to BIPP because of the nitrogen removal metabolism and extracellular polymeric substance (EPS). Heterotrophic nitrogen removal metabolism was the driving force of BIPP, while EPS with abundant carboxyl and amide groups promoted the precipitation. The study would provide new insights into simultaneous nutrients removal and P recovery from wastewater.

Due to the ultrathin thickness and dangling-bond-free surface, 2D materials have been regarded as promising candidates for future nanoelectronics. In recent years, group-VI elemental 2D materials have been rediscovered and found superior in electrical properties (e.g., high carrier mobility, high photoconductivity, and thermoelectric response). The outstanding semiconducting properties of group-VI elemental 2D materials enable device applications including high-performance field-effect transistors and optoelectronic devices. The excellent environmental stability also facilitates fundamental studies and practical applications of group-VI elemental 2D materials. This Review first focuses on the crystal structures of group-VI elemental 2D materials. Afterward, preparation methods for nanostructures of group-VI materials are introduced with comprehensive studies. A brief Review of the electronic structures is then presented with an understanding of the electrical properties. This Review also contains the device applications of group-VI elemental 2D materials, emphasizing transistors, photodetectors, and other appealing applications. Finally, this Review provides an outlook for the development of group-VI elemental 2D materials, highlighting the challenges and opportunities in fundamental studies and technological applications.

The purpose of this research was to assess the feasibility of simultaneous partial nitrification, ANAMMOX and denitrification (SNAD) for mature landfill leachate treatment under low temperature. To this end, bench-scale bioreactors receiving ammonium-rich wastewater were adapted to progressively reduced temperature after 370-day operation (Period I), and subsequently acclimatized to raw leachate for 86 days (Period II). Maximum nitrogen removal rates (NRR) of 218.9, 211.9, 201.1 and 146.9 g N m−3 d−1 were achieved at 30 °C, 20 °C, 15 °C and 10 °C respectively during Period I, mainly ascribing to partial nitritation/ANAMMOX. Furthermore, the SNAD bioreactor turned out to be feasible for prolonged treatment of mature landfill leachate under 15 °C (Period II), with simultaneous degradation of nitrogen (207.9 g N m−3 d−1) and bio-refractory organics (94.9 g COD m−3 d−1) respectively. High-throughput sequencing implied that better denitrogenation performance during Period II might be ascribed to reappearance of denitrifying bacteria (9.88%) and complete suppression of nitrite oxidation bacteria (NOB), although ammonium oxidation bacteria (AOB) and ANAMMOX bacteria (AMX) decreased by 6.05% and 4.56% respectively. Furthermore, the enriched bio-refractory organics degradation bacteria (24.38%) were conductive to the performance robustness. This research presents perspective for the application of efficient treatment of mature landfill leachate under low temperature.

Cost-effective, highly efficient, and durable catalyst electrodes play a critical role in large-scale water splitting. Although bimetallic phosphides show great potential in electrocatalytic water splitting, the synergistic effect between different active sites has not been investigated to date in detail, which implies lack of an effective strategy to optimize the water splitting performance in a reasonable way. Here we realize robust oxygen evolution (OER) performance with an extremely low overpotential (500 mA cm−2@255 mV), low Tafel slope (29.1 mV dec−1), and superior stability by controlling the Fe sites on the Ni–Fe–P surface. The prepared OER electrode employs non-noble metal catalysts for superior oxygen evolution performance and meets the requirements of commercial water electrolyzers. In addition, remarkable hydrogen evolution (HER) performance with prominent stability is also achieved by reducing the content of Fe dopant. Our theoretical calculations reveal that improved chemisorption of O-containing intermediates induced by Fe doping contributes to the enhanced OER performance and water molecule chemisorption, which is sensitive to the Fe content, is the primary cause affecting alkaline HER performance. This work highlights controllable water splitting performance on the Ni–Fe–P surface by precisely manipulating the surface active Fe-sites.

Robust hydrogen evolution reaction (HER) in alkaline solution using a cost-effective catalyst is still a critical challenge for industrial H2O electrolysis. The dramatic depletion of interfacial H2O and hindered OH− diffusion bring about a harsh interfacial environment and thereby lead to sluggish hydrogen evolution. Here we develop heterogeneous catalysts based on defect-rich three-dimensional graphene (M/3D graphene) and achieve improved HER kinetics via surface hydroxyl group modification on the graphene surface. Our theoretical studies suggest that the surface hydroxyl groups derived from the hydroxylation process effectively attract multi-overlayer H2O clusters without any thermodynamic barrier and form a reservoir to continuously supply H2O for catalytic sites. Electrochemical characterizations indicate that the HER kinetics per active electrochemical surface area have been greatly improved after crafting abundant hydroxyl groups on the 3D graphene framework, which can be attributed to sufficient proton donors and an ameliorative interfacial pH environment. Benefiting from the surface hydroxyl group modification, the MoS2/3D graphene structure facilitates the HER at a low onset potential of 60 mV in alkaline medium and exhibits excellent durability after 3000 cycles. This surface modification strategy reveals the importance of interfacial H2O supply in HER kinetics and provides general guidance on designing highly efficient catalysts in alkaline medium.

To reveal nitrogen removal mechanisms under environmental stresses, biofilm reactors were operated at different temperatures (10 °C–35 °C) treating saline wastewater (salinity 3%). The results showed nitrogen removal efficiency was 98.46% at 30 °C and 60.85% at 10 °C, respectively. Both ammonia oxidizing archaea (AOA) and ammonia oxidizing bacteria (AOB) participated in nitrification. 94.9% of the overall ammonia oxidation was attributed to AOA at 10 °C, but only 48.2% of that was undertaken by AOA at 35 °C. AOA had a greater contribution at low temperature, which demonstrated that nitrogen removal pathway varied with temperature. Aerobic denitrification was more stable than anoxic denitrification. High-throughput sequencing showed Crenarchaeota was the dominant AOA (97.02–34.47%), cooperating with various heterotrophic AOB. Real-time PCR indicated that AOA was three orders of magnitude more abundant than AOB. AOA was more resistant to low temperature and high-saline stresses. Ammonia oxidizers had distinct responses to temperature change and showed diverse relationships at different temperatures.

High salinity and high organic concentration impose negative impacts on autotrophic nitrification, which hinders efficient nitrogen removal. To achieve efficient nitrogen removal, high saline wastewater nitrogen removal systems with different COD/TN ratios based on heterotrophic nitrification-aerobic denitrification (HN-AD) process were established in this study. Results demonstrated that the COD/TN ratio had significant effects on nitrogen removal efficiency, microbial community structures and metabolic pathways. The optimal COD/TN ratio was 25 for nitrogen removal, with NH4+-N and TN removal rates of 11.86 mg·L−1·h−1 and 11.50 mg·L−1·h−1, respectively (3.65 and 3.31 times higher than those COD/TN ratio of 10). 16S rRNA high-throughput sequencing revealed that HN-AD functional bacteria (Pseudomonas, Bacillus, Paracoccus) with highest abundance (7.61%) played a key role in high saline wastewater treatment. And Halomonas, Nitrincola and Oceanimonas participated in the denitrification process. Moreover, the abundance of genes related to nitrogen removal was the highest (1.90%) revealed by functional genes prediction.

Ag nanostructures are widely used in catalysis, energy conversion and chemical sensing. Morphology-tailored synthesis of Ag nanostructures is critical to tune physical and chemical properties. In this study, we develop a method for synthesizing the morphology-tailored Ag nanostructures in aqueous solution at a low temperature (45 °C). With the use of AgCl nanoparticles as the precursor, the growth kinetics of Ag nanostructures can be tuned with the pH value of solution and the concentration of Pd cubes which catalyze the reaction. Ascorbic acid and cetylpyridinium chloride are used as the mild reducing agent and capping agent in aqueous solution, respectively. High-yield Ag nanocubes, nanowires, right triangular bipyramids/cubes with twinned boundaries, and decahedra are successfully produced. Our method opens up a new environmentally-friendly and economical route to synthesize large-scale and morphology-tailored Ag nanostructures, which is significant to the controllable fabrication of Ag nanostructures and fundamental understanding of the growth kinetics.

Nesprins-1 and -2 are highly expressed in skeletal and cardiac muscle and together with SUN (Sad1p/UNC84)-domain containing proteins and lamin A/C form the LInker of Nucleoskeleton-and-Cytoskeleton (LINC) bridging complex at the nuclear envelope (NE). Mutations in nesprin-1/2 have previously been found in patients with autosomal dominant Emery–Dreifuss muscular dystrophy (EDMD) as well as dilated cardiomyopathy (DCM). In this study, three novel rare variants (R8272Q, S8381C and N8406K) in the C-terminus of the SYNE1 gene (nesprin-1) were identified in seven DCM patients by mutation screening. Expression of these mutants caused nuclear morphology defects and reduced lamin A/C and SUN2 staining at the NE. GST pull-down indicated that nesprin-1/lamin/SUN interactions were disrupted. Nesprin-1 mutations were also associated with augmented activation of the ERK pathway in vitro and in hearts in vivo. During C2C12 muscle cell differentiation, nesprin-1 levels are increased concomitantly with kinesin light chain (KLC-1/2) and immunoprecipitation and GST pull-down showed that these proteins interacted via a recently identified LEWD domain in the C-terminus of nesprin-1. Expression of nesprin-1 mutants in C2C12 cells caused defects in myoblast differentiation and fusion associated with dysregulation of myogenic transcription factors and disruption of the nesprin-1 and KLC-1/2 interaction at the outer nuclear membrane. Expression of nesprin-1α2 WT and mutants in zebrafish embryos caused heart developmental defects that varied in severity. These findings support a role for nesprin-1 in myogenesis and muscle disease, and uncover a novel mechanism whereby disruption of the LINC complex may contribute to the pathogenesis of DCM.

Two-dimensional MoS2 is a promising material for future nanoelectronics and optoelectronics. It has remained a great challenge to grow large-size crystalline and high surface coverage monolayer MoS2. In this work, we investigate the controllable growth of monolayer MoS2 evolving from triangular flakes to continuous thin films by optimizing the concentration of gaseous MoS2, which has been shown a both thermodynamic and kinetic growth factor. A single-crystal monolayer MoS2 larger than 300 μm was successfully grown by suppressing the nuclei density and supplying sufficient source. Furthermore, we present a facile process of transferring the centimeter scale MoS2 assisted with a copper thin film. Our results show the absence of observable residues or wrinkles after we transfer MoS2 from the growth substrates onto flat substrates using this technique, which can be further extended to transfer other two-dimensional layered materials.