Defoliation, trampling and nutrient return differentially influence grassland productivity by modulating trait-dependent plant community composition: insights from a simulated grazing experiment.

Ungulate grazing involves multiple components, including defoliation, dung and urine return, and trampling, which supply offsetting or synergistic effects on plant community composition and productivity (ANPP), but these effects have not been fully studied. Plant functional traits may reflect the response of plants to disturbance and their impact on ecosystem functions. Species turnover and intraspecific trait variation (ITV) are important drivers of community trait composition. We conducted a simulated grazing experiment in a steppe grassland in northern China to examine the effects of defoliation, dung and urine return, and trampling on community-weighted mean (CWM), functional diversity (FD) and ANPP, and to disentangle the roles of species turnover and ITV in driving these changes. We found that defoliation had a dominant effect on CWMs and FDs of all four traits through species turnover and ITV, respectively, resulting in a convergence of traits towards as more resource-acquisitive strategy. Dung-urine return resulted in more resource-acquisitive community traits mainly through ITV, whereas there were no significant effects on FDs except for leaf C/N. Trampling increased CWM of leaf dry matter content primarily driven by ITV, and had no significant effect on FDs. Furthermore, our simulated grazing positively affected ANPP, primarily due to nutrient additions from dung and urine, and ITV largely explained the variation in ANPP. These findings highlight the multifaceted effects of grazing components on community structure and ANPP, and the significance of ITV in shaping grassland plant communities and productivity.

Protists play important roles in the assembly and stability of denitrifying bacterial communities in copper-tailings drainage.

Unraveling the drivers controlling the assembly and stability of functional communities is a central issue in ecology. Despite extensive research and data, relatively little attention has been paid on the importance of biotic factors and, in particular, on the trophic interaction for explaining the assembly of microbial community. Here, we examined the diversity, assembly, and stability of nirS-, nirK-, and nosZ-type denitrifying bacterial communities in copper-tailings drainages of the Shibahe tailings reservoir in Zhongtiao Mountain, China's. We found that components of nirS-, nirK-, and nosZ-type denitrifying bacterial community diversity, such as taxon relative abundance, richness, and copy number, were strongly correlated with protist community composition and diversity. Assembly of the nirK-type denitrifying bacterial community was governed by dispersal limitation, whereas those of nirS- and nosZ-type communities were controlled by homogeneous selection. The relative importance of protist diversity in the assembly of nirK- and nosZ-type denitrifying bacterial communities was greater than that in nirS-type assembly. In addition, protists reduced the stability of the co-occurrence network of the nosZ-type denitrifying bacterial community. Compared with eukaryotic algae, protozoa had a greater impact on the stability of denitrifying bacterial community co-occurrence networks. Generally, protists affected the assembly and community stability of denitrifying bacteria in copper-tailings drainages. Our findings thus emphasize the importance of protists on affecting the assembly and community stability of denitrifying bacteria in copper-tailings drainages and may be useful for predicting changes in the ecological functions of microorganisms.

Climate, not grazing, influences soil microbial diversity through changes in vegetation and abiotic factors on geographical patterns in the Eurasian steppe.

Livestock grazing has a significant impact on the biodiversity of nature grassland ecosystems, which is mainly regulated by climate factors. Soil microbes are essential components of biogeochemical cycles. However, the coupling effects of grazing with MAT (mean annual temperature) and MAP (mean annual precipitation) on soil microbial communities remain inconsistent. Our study considered the various climates in four grasslands as natural temperature and precipitation gradients combined with grazing intensity (GI). We collected and analyzed vegetation and soil physiochemical properties from four grasslands. Our results showed that climate factors (CF) changed ß diversity of soil bacteria and fungi while grazing intensity and their interaction merely affected fungi ß diversity. Furthermore, climate factors and grazing intensity impacted changes in vegetation and soil physiochemical properties, with their interaction leading to changes in EC and MBC. Our analysis revealed that climate factors contributed 13.1% to bacteria community variation while grazing intensity contributed 3.01% to fungi community variation. Piecewise SEM analysis demonstrated that MAT and MAP were essential predictors of bacteria ß diversity, which was significantly affected by vegetation and soil carbon and nitrogen. At the same time, MAP was an essential factor of fungi ß diversity and was mainly affected by soil nitrogen. Our study indicated that bacteria and fungi ß diversity was affected by different environmental processes and can adapt to specific grazing intensities over time.

A Nonlinear-Model-Based High-Bandwidth Current Sensor Design for Switching Current Measurement of Wide Bandgap Devices.

With the growing adoption of wide bandgap devices in power electronic applications, current sensor design for switching current measurement has become more important. The demands for high accuracy, high bandwidth, low cost, compact size, and galvanic isolation pose significant design challenges. The conventional modeling approach for bandwidth analysis of current transformer sensors assumes that the magnetizing inductance remains constant, which does not always hold true in high-frequency operations. This can result in inaccurate bandwidth estimation and affect the overall performance of the current sensor. To address this limitation, this paper provides a comprehensive analysis of nonlinear modeling and bandwidth, considering the varying magnetizing inductance in a wide frequency range. A precise and straightforward arctangent-based fitting algorithm was proposed to accurately emulate the nonlinear feature, and the fitting results were compared with the magnetic core's datasheet to confirm its accuracy. This approach contributes to more accurate bandwidth prediction in field applications. In addition, the droop phenomenon of the current transformer and saturation effects are analyzed in detail. For high-voltage applications, different insulation methods are compared and an optimized insulation process is proposed. Finally, the design process is experimentally validated. The bandwidth of the proposed current transformer is around 100 MHz and the cost is around $20, making it a low-cost and high-bandwidth solution for switching current measurements in power electronic applications.

Macrofungi promote SOC decomposition and weaken sequestration by modulating soil microbial function in temperate steppe.

Soil organic carbon (SOC) sequestration is a key grassland ecosystem function, and the magnitude of SOC reservoirs depends on microbial involvement, especially that of fungi. Mycelia developed by macrofungi potentially influence carbon (C) fixation and decomposition; however, the mechanisms underlying their effects on SOC storage in grassland ecosystems remain poorly understood. The fairy rings formed by macrofungi in grasslands are natural platform for exploring macrofungal effects on SOC. In this study, we collected topsoil (0-10 cm) from four different fairy ring zones in a temperate steppe to reveal the macrofungal effects on SOC fractions, including particulate organic carbon (POC) and mineral-associated organic carbon (MAOC), and the SOC storage microbial mechanism using metagenomic sequencing technology. Both POC and MAOC decreased after macrofungal passage, resulting in a 7.37 % reduction in SOC. Macrofungal presence reduced microbial biomass carbon (MBC), but significantly enhanced the ß-1,4-glucosidase (BG) activity, which increased dissolved organic carbon (DOC). In addition, the abundance of copiotrophs (Proteobacteria and Bacteroidetes) with lower C metabolic rates increased, and that of oligotrophs (Actinobacteria, Acidobacteria, Chloroflexi, and Verrucomicrobia) with higher substrate utilization efficiency decreased in the presence of macrofungi. This may further promote SOC decomposition. Correspondingly, there was a lower abundance of C-fixation genes but more C-degradation genes (especially hemicellulosic degradation genes) during macrofungal passage. Our results indicate that the presence of macrofungi can modulate the soil microbial community and functional genes to reduce SOC storage by inhibiting microbial C sequestration while promoting C decomposition in grassland ecosystems. These findings refine our mechanistic understanding of SOC persistence through the interactions between macrofungi and other microbes.

Dental erosion caused by glucocorticoid therapy in a patient with optic neuritis: a case report.

Dental erosion is characterized by progressively destroyed teeth, which has no relation to bacteria but to chemicals. Some internal factors, such as gastroesophageal reflux induced by bulimia, anorexia, gastrointestinal diseases, or drugs, and external factors, such as diet, drugs, and occupational acid exposure, are considered promotive factors for this disease. This article presents a patient suffering from severe dental erosion in the whole dentition, especially in the maxillary teeth, due to gastroesophageal reflux induced by glucocorticoid therapy for optic neuritis. This article discusses the mechanism between optic neuritis glucocorticoid therapy and dental erosion.

Mowing Facilitated Shoot and Root Litter Decomposition Compared with Grazing.

Shoot and root litter are two major sources of soil organic carbon, and their decomposition is a crucial nutrient cycling process in the ecosystem. Altitude and land use could affect litter decomposition by changing the environment in mountain grassland ecosystems. However, few studies have investigated the effects of land use on litter decomposition in different altitudes. We examined how land-use type (mowing vs. grazing) affected shoot and root litter decomposition of a dominant grass (Bromus inermis) in mountain grasslands with two different altitudes in northwest China. Litterbags with 6 g of shoot or root were fixed in the plots to decompose for one year. The mass loss rate of the litter, and the environmental attributes related to decomposition, were measured. Litter decomposed faster in mowing than grazing plots, resulting from the higher plant cover and soil moisture but lower bulk density, which might promote soil microbial activities. Increased altitude promoted litter decomposition, and was positively correlated with soil moisture, soil organic carbon (SOC), and ß-xylosidase activity. Our results highlight the diverse influences of land-use type on litter decomposition in different altitudes. The positive effects of mowing on shoot decomposition were stronger in lower than higher altitude compared to grazing due to the stronger responses of the plant (e.g., litter and aboveground biomass) and soil (e.g., soil moisture, soil bulk density, and SOC). Soil nutrients (e.g., SOC and soil total nitrogen) seemed to play essential roles in root decomposition, which was increased in mowing plots at lower altitude and vice versa at higher altitude. Therefore, grazing significantly decreased root mass loss at higher altitude, but slightly increased at lower altitude compared to mowing. Our results indicated that the land use might variously regulate the innate differences of the plant and edaphic conditions along an altitude gradient, exerting complex impacts in litter decomposition and further influencing carbon and nutrient cycling in mountain grasslands.

Effectiveness of five-element music therapy in cancer patients: A systematic review and meta-analysis.

OBJECTIVE: To systematically evaluate the effectiveness of five-element music therapy on anxiety, depression, quality of life (QoL), sleep quality and Karnofsky performance score (KPS) in cancer patients. METHODS: We searched English databases (PubMed, Cochrane Library, Embase, Web of Science) and Chinese databases (CNKI, WanFang, CBM and VIP database) from the inception to December 25, 2020. Two investigators independently screened literature, extracted data, and assessed risk of bias according to the eligibility criteria. The RevMan 5.3 software was used to perform the meta-analysis. RESULTS: A total of 22 studies, 2053 people with cancer were included. Meta-analysis showed that five-element music therapy had a significant difference for relieving depression (SMD = -1.11, 95% CI: 1.41 to -0.82, P < 0.00001), QoL (SMD = 1.41, 95% CI:0.58 to 2.23, P = 0.0008), sleep quality (MD = -1.73, 95% CI: 2.34 to -1.12, P < 0.00001), and KPS (MD = 4.75, 95% CI:2.31 to 7.18, P = 0.0001). And five-element music therapy did not show a positive effect on anxiety (SMD = -0.60, 95% CI: 1.47 to 0.27, P = 0.17). CONCLUSIONS: Five-element music therapy had a positive effect on depression, QoL, sleep quality, and KPS in cancer patients, while did not show a positive effect on anxiety. Future researchers need to optimize the research program and conduct more high-quality, large sample, multi-center randomized controlled studies. Besides, it would be helpful for future researchers to explain the five-element music therapy being examined and how it is potentially useful in western contexts.

Transcriptome analysis of genes and pathways associated with salt tolerance in alfalfa under non-uniform salt stress.

Soil salinity of fields is often non-uniform. To obtain a better understanding of molecular response to non-uniform salt stress, we conducted transcriptomic analysis on the leaves and roots of alfalfa grown under 0/0, 200/200, and 0/200 mM NaCl treatments. A total of 233,742 unigenes were obtained from the assembled cDNA libraries. There were 98 and 710 unigenes identified as significantly differentially expressed genes (DEGs) in the leaves of non-uniform and uniform salt treatment, respectively. Furthermore, there were 5178 DEGs in the roots under uniform salt stress, 273 DEGs in the non-saline side and 4616 in the high-saline side roots under non-uniform salt stress. Alfalfa treated with non-uniform salinity had greater dry weight and less salt damage compared to treatment with uniform salinity. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of the DEGs in roots revealed that both sides of the non-uniform salinity were enriched in pathways related to "phenylpropanoid biosynthesis" and "linoleic acid metabolism"; and "MAPK signaling pathway-plant" was also indicated as a key pathway in the high-saline roots. We also combined a set of important salt-response genes and found that roots from the non-saline side developed more roots with increased water uptake by altering the expression of aquaporins and genes related to growth regulation. Moreover, the hormone signal transduction and the antioxidant pathway probably play important roles in inducing more salt-related genes and increasing resistance to non-uniform salt stress on both sides of the roots.

A methylation functional detection hepatic cell system validates correlation between DNA methylation and drug-induced liver injury.

Drug-induced liver injury (DILI) is a life-threatening, adverse reaction to certain drugs. The onset and extent of DILI can vary drastically in different patients using identical drugs. Association studies suggested that subtle differences in DNA methylation may help explain the individual differences in DILI. However, there are very few experimental methods to confirm such associations. In this study, we established a novel DNA methylation functional detection system in human hepatocytes, using CRISPR/dCas9 for targeted modification of DNA methylation, and set four parameters to indicate the liver injury by cell model. Using this system, we validated the association of hypermethylation of CYP2D6 and CYP2E1 with rifampin-induced DILI. Our results revealed that, following treatment of HepaRG cells with rifampin, the methylation levels of CYP2D6 and CYP2E1 were inversely proportional to cell viability and glutathione content, and directly proportional to caspase 3/7 activity. We expect that our methylation detection system will serve as a useful tool in validating correlations between DNA methylation and DILI in other in vitro systems. Our results establish a foundation for future investigations to better understand the mechanisms underlying DILI and may aid in advancing personalized DILI medicine.

Genome-Wide Analysis of DNA Methylation and Antituberculosis Drug-Induced Liver Injury in the Han Chinese Population.

Tuberculosis (TB) is one of the most prevalent infections. However, anti-TB drugs induce adverse liver injury in up to 40% of patients. Studies on candidate genes have suggested that single-nucleotide polymorphisms account for only a small contribution to the occurrence of anti-TB drug-induced liver injury (ATLI). In this study, whole-genome DNA methylation analysis was performed to systematically screen the ATLI-associated factors in a 49 vs. 51 case-control population. Next, 34 identified candidate probes were validated using MassARRAY in 296 cases and 288 controls. Our results indicated that 12 CpG sites on seven probes were positively associated with ATLI risk. Furthermore, we applied a CRISPR/Cas9-mediated methylation modifiable cell model and demonstrated that four CpGs in or near the gene region of AK2, SLC8A2, and PSTPIP2 affected the cellular response to rifampicin treatment. This study provides new biomarkers associated with ATLI occurrence.

Combining Orchardgrass and Alfalfa: Effects of Forage Ratios on In Vitro Rumen Degradation and Fermentation Characteristics of Silage Compared with Hay.

This study aimed to investigate the effects of different forage ratios of orchardgrass (Dactylis glomerata) and alfalfa (Medicago sativa) on in vitro rumen degradation and fermentation characteristics. Orchardgrass and alfalfa were harvested separately and prepared as hay and silage mixtures at ratios of 100:0, 75:25, 50:50, 25:75, and 0:100 (w/w on a dry matter basis) and anaerobically incubated for 48 h with rumen fluid obtained from lactating dairy cows. Fermented residues and cultured fluids were used to determine nutrient degradability, fermentation parameters, and associative effect indices. Increasing the proportion of alfalfa in hay and silage mixtures quadratically increased in vitro organic matter disappearance (IVOMD, up +5.14%) and marginally decreased in vitro neutral detergent fiber disappearance (NDFD, down -1.79%). Meanwhile, increasing the proportion of alfalfa accelerated the rumen fermentation process (e.g., gas production) and remarkably enhanced the growth of rumen microbes as indicated by microbial protein production (MCP, 13.4% increase). Increments of rumen degradability and methane production were more pronounced in silage mixtures than hay mixtures. In combination, a forage ratio of 50:50 for orchardgrass and alfalfa is recommended for both hay and silage in order to improve the feed use potential in ruminants.

Effects of non-uniform root zone salinity on growth, ion regulation, and antioxidant defense system in two alfalfa cultivars.

A split-root system was established to investigate the effects of uniform (0/0, 50/50, and 200/200 mM salt [NaCl]) and non-uniform (0/200 and 50/200 mM NaCl) salt stress on growth, ion regulation, and the antioxidant defense system of alfalfa (Medicago sativa) by comparing a salt-tolerant (Zhongmu No.1) and salt-sensitive (Algonquin) cultivar. We found that non-uniform salinity was associated with greater plant growth rate and shoot dry weight, lower leaf Na+ concentration, higher leaf potassium cation (K+) concentration, lower lipid peroxidation, and greater superoxide dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6), and peroxidase (EC 1.11.1.7) activities, compared to uniform salt stress in both alfalfa cultivars. Under non-uniform salinity, a significant increase in Na+ concentration and Na+ efflux and a decline in K+ efflux in the no-saline or low-saline part of the roots alleviated salt damage. Our results also demonstrated that proline and antioxidant enzymes accumulated in both the no- or low-saline and high-saline roots, revealing that osmotic adjustment and antioxidant defense had systemic rather than localized effects in alfalfa plants, and there was a functional equilibrium within the root system under non-uniform salt stress. The salt-tolerant cultivar Zhongmu No.1 exhibited greater levels of growth compared to Algonquin under both uniform and non-uniform salt stress, with Na+ tolerance and efflux abilities more effective and greater antioxidant defense capacity evident for cultivar Zhongmu No.1.