Low soil phosphorus (P) bioavailability causes the widespread occurrence of P‐limited terrestrial ecosystems around the globe. Exploring the factors influencing soil P bioavailability at large ...spatial scales is critical for managing these ecosystems. However, previous studies have mostly focused on abiotic factors. In this study, we explored the effects of microbial factors on soil P bioavailability of terrestrial ecosystems using a country‐scale sampling effort. Our results showed that soil microbial biomass carbon (MBC) and acid phosphatase were important predictors of soil P bioavailability of agro‐ and natural ecosystems across China although they appeared less important than total soil P. The two microbial factors had a positive effect on soil P bioavailability of both ecosystem types and were able to mediate the effects of several abiotic factors (e.g., mean annual temperature). Meanwhile, we revealed that soil phytase could affect soil P bioavailability at the country scale via ways similar to those of soil MBC and acid phosphatase, a pattern being more pronounced in agroecosystems than in natural ecosystems. Moreover, we obtained evidence for the positive effects of microbial genes encoding these enzymes on soil P bioavailability at the country scale although their effect sizes varied between the two ecosystem types. Taken together, this study demonstrated the remarkable effects of microbial factors on soil P bioavailability at a large spatial scale, highlighting the importance to consider microbial factors in managing the widespread P‐limited terrestrial ecosystems.
Understanding the factors influencing soil phosphorus (P) bioavailability at large spatial scales is critical to the development of managing strategies for P‐limited terrestrial ecosystems around the globe. However, previous studies have mostly focused on abiotic factors. Here, we explored the effects of not only abiotic factors but also microbial factors on soil P bioavailability of terrestrial ecosystems using a country‐scale sampling effort in China. We demonstrated that soil microbial biomass carbon (MBC), organic P‐mineralizing enzymes and microbial genes encoding these enzymes were important predictors of soil P bioavailability of agro‐ and natural ecosystems across China.
Abstract
The coronavirus disease of 2019 (COVID-19) has caused a global pandemic and led to nearly three million deaths globally. As of April 2021, there are still many countries that do not have ...COVID-19 vaccines. Before the COVID-19 vaccines were developed, some evidence suggested that an influenza vaccine may stimulate nonspecific immune responses that reduce the risk of COVID-19 infection or the severity of COVID-19 illness after infection. This study evaluated the association between influenza vaccination and the risk of COVID-19 infection. We conducted a retrospective cross-sectional study with data from July 1, 2019, to June 30, 2020 with the Claims data from Symphony Health database. The study population was adults age 65 years old or older who received influenza vaccination between September 1 and December 31 of 2019. The main outcomes and measures were odds of COVID-19 infection and severe COVID-19 illness after January 15, 2020. We found the adjusted odds ratio (aOR) of COVID-19 infection risk between the influenza-vaccination group and no-influenza-vaccination group was 0.76 (95% confidence interval (CI), 0.75–0.77). Among COVID-19 patients, the aOR of developing severe COVID-19 illness was 0.72 (95% CI, 0.68–0.76) between the influenza-vaccination group and the no-influenza-vaccination group. When the influenza-vaccination group and the other-vaccination group were compared, the aOR of COVID-19 infection was 0.95 (95% CI, 0.93–0.97), and the aOR of developing a severe COVID-19 illness was 0.95 (95% CI, 0.80–1.13). The influenza vaccine may marginally protect people from COVID-19 infection.
Van der Waals (vdW) heterostructures (HSs) built on 2D materials provide an ideal platform for research of energy migration at the nanoscale. However, the underlying charge transfer mechanism in type ...II vdW HSs is still not well understood. Here, ultrafast exciton dynamics are investigated in trilayer‐WS2‐MoS2‐WSe2 and trilayer‐MoS2‐WSe2‐WS2 HSs by broadband pump‐probe spectroscopy. A two‐step process of exciton transfer in trilayer‐WS2‐MoS2‐WSe2 is directly observed when the band edge exciton of WSe2 is excited. The electrons in WSe2 are initially transferred to the high lying electronic state of MoS2‐WS2 on a time scale of tens of femtoseconds, and then electrons eventually relax into the conduction band minimum of MoS2 within 1 ps. Furthermore, the transfer of interlayer excitons is observed for the first time in trilayer‐MoS2‐WSe2‐WS2. Both transfer processes can be better understood by the Dexter charge exchange model. Due to the nature of Dexter type transfer that the exchange rate exponentially depends on the donor−acceptor distance, the interlayer exciton transfer rate is nearly a hundred times slower than that of exciton transition in bilayer HSs. The results deepen the understanding of charge transfer in 2D vdW HSs and also indicate that the exciton effect and orbital hybridization make HS a strong coupling system.
A two‐step process of charge transfer in trilayer‐WS2–MoS2–WSe2 is directly observed when WSe2 is excited. The electrons in WSe2 are transferred to the high lying electronic state of MoS2–WS2, and then electrons eventually relax into the conduction band minimum of MoS2. In addition, the transfer of interlayer excitons is observed for the first time.
Luminescent metal clusters have attracted great interest in current research; however, the design synthesis of Al clusters with color‐tunable luminescence remains challenging. Herein, an ...Al8(OH)8(NA)16 (Al8, HNA = nicotinic acid) molecular cluster with dual luminescence properties of fluorescence and room‐temperature phosphorescence (RTP) is synthesized by choosing HNA ligand as phosphor. Its prompt photoluminescence (PL) spectrum exhibits approximately white light emission at room temperature. Considering that halogen atoms can be used to regulate the RTP property by balancing the singlet and triplet excitons, different CdX2 (X− = Cl−, Br−, I−) are introduced into the reactive system of the Al8 cluster, and three new Al8 cluster‐based metal‐organic frameworks, {Al8Cd3Cl5(OH)8(NA)17H2O·2HNA}n (CdCl2‐Al8), {Al8Cd4Br7(OH)8(NA)16CH3CN·NA·HNA}n (CdBr2‐Al8) and {Al8Cd8I16(OH)8(NA)16}n (CdI2‐Al8) are successfully obtained. They realize the color tunability from blue to yellow at room temperature. The origination of fluorescence and phosphorescence has also been illustrated by structure‐property analysis and theoretical calculation. This work provides new insights into the design of multicolor luminescent metal cluster‐based materials and develops advanced photo‐functional materials for multicolor display, anti‐counterfeiting, and encryption applications.
By fixing a phosphor of nicotinic acid into crystalline state, an Al8 cluster with dual luminescent properties of fluorescence and room‐temperature phosphorescence (RTP) is obtained. Introducing CdX2 into the reactive system of the Al8 cluster to regulate RTP by balancing the singlet and triplet excitons, three heterometallic Al8‐based metal‐organic frameworks are obtained. They realize the luminescent color tunability from blue to yellow.
ABSTRACT
Phosphate‐solubilizing microbes (PSMs) drive the biogeochemical cycling of phosphorus (P) and hold promise for sustainable agriculture. However, their global distribution, overall diversity ...and application potential remain unknown. Here, we present the first synthesis of their biogeography, diversity and utility, employing data from 399 papers published between 1981 and 2017, the results of a nationwide field survey in China consisting of 367 soil samples, and a genetic analysis of 12986 genome‐sequenced prokaryotic strains. We show that at continental to global scales, the population density of PSMs in environmental samples is correlated with total P rather than pH. Remarkably, positive relationships exist between the population density of soil PSMs and available P, nitrate‐nitrogen and dissolved organic carbon in soil, reflecting functional couplings between PSMs and microbes driving biogeochemical cycles of nitrogen and carbon. More than 2704 strains affiliated with at least nine archaeal, 88 fungal and 336 bacterial species were reported as PSMs. Only 2.59% of these strains have been tested for their efficiencies in improving crop growth or yield under field conditions, providing evidence that PSMs are more likely to exert positive effects on wheat growing in alkaline P‐deficient soils. Our systematic genetic analysis reveals five promising PSM genera deserving much more attention.
Several recent studies have shown the presence of genes for the key enzyme associated with archaeal methane/alkane metabolism, methyl-coenzyme M reductase (Mcr), in metagenome-assembled genomes ...(MAGs) divergent to existing archaeal lineages. Here, we study the mcr-containing archaeal MAGs from several hot springs, which reveal further expansion in the diversity of archaeal organisms performing methane/alkane metabolism. Significantly, an MAG basal to organisms from the phylum Thaumarchaeota that contains mcr genes, but not those for ammonia oxidation or aerobic metabolism, is identified. Together, our phylogenetic analyses and ancestral state reconstructions suggest a mostly vertical evolution of mcrABG genes among methanogens and methanotrophs, along with frequent horizontal gene transfer of mcr genes between alkanotrophs. Analysis of all mcr-containing archaeal MAGs/genomes suggests a hydrothermal origin for these microorganisms based on optimal growth temperature predictions. These results also suggest methane/alkane oxidation or methanogenesis at high temperature likely existed in a common archaeal ancestor.
Nitric oxide (NO) has been shown to play an important role in the plant response to biotic and abiotic stresses in Arabidopsis mutants with lower or higher levels of endogenous NO. The exogenous ...application of NO donors or scavengers has also suggested an important role for NO in plant defense against environmental stress. In this study, rice plants under drought and high salinity conditions showed increased nitric oxide synthase (NOS) activity and NO levels. Overexpression of rat neuronal NO synthase (nNOS) in rice increased both NOS activity and NO accumulation, resulting in improved tolerance of the transgenic plants to both drought and salt stresses. nNOS-overexpressing plants exhibited stronger water-holding capability, higher proline accumulation, less lipid peroxidation and reduced electrolyte leakage under drought and salt conditions than wild rice. Moreover, nNOS-overexpressing plants accumulated less H2O2, due to the observed up-regulation of OsCATA, OsCATB and OsPOX1. In agreement, the activities of CAT and POX were higher in transgenic rice than wild type. Additionally, the expression of six tested stress-responsive genes including OsDREB2A, OsDREB2B, OsSNAC1, OsSNAC2, OsLEA3 and OsRD29A, in nNOS-overexpressing plants was higher than that in the wild type under drought and high salinity conditions. Taken together, our results suggest that nNOS overexpression suppresses the stress-enhanced electrolyte leakage, lipid peroxidation and H2O2 accumulation, and promotes proline accumulation and the expression of stress-responsive genes under stress conditions, thereby promoting increased tolerance to drought and salt stresses.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Purpose
To analyze health-related quality of life (HRQoL) and related factors among elderly persons receiving community-based home care and institutional care in Guangzhou, a large city of mainland ...China.
Methods
A representative sample of 1600 subjects aged 60 years and over residing in communities and nursing homes was randomly selected through stratified sampling. The 12-item Short Form Health Survey version 2 (SF-12v2) was used to assess HRQoL.
Results
In total, 1014 elderly persons under different aged care models responded to the survey (response rate 63.4%) and 1000 were eligible for data analyses. Compared with the elderly receiving community-based home care or private institutional care, those in public institutional care had the lowest scores on the physical component summary (PCS, 36.89 ± 10.44) and the mental component summary (MCS, 47.16 ± 11.14). Number of chronic diseases, loneliness, and age were the most common significant factors (
P
< 0.05) affecting PCS and MCS. The interaction term between aged care model and number of chronic diseases significantly affected PCS (
β
= − 0.165,
P
< 0.05), indicating a stronger association between these factors for participants receiving community-based home care than institutional care. The interaction term between aged care model and loneliness had a significant effect on MCS (
β
= 0.189,
P
< 0.05), indicating a weaker association between loneliness and MCS for participants receiving community-based home care.
Conclusions
This study found poor HRQoL among the elderly in Guangzhou. The main factors associated with the physical and mental HRQoL of elderly persons included number of chronic diseases, loneliness, age, and education level. It also revealed the moderating effects of aged care model on HRQoL, suggesting specific health management strategies for elderly in community-based home care and institutional care, respectively.
The present study was performed to investigate the therapeutic performance of polymer‐lipid hybrid nanoparticles towards the delivery of lapatinib (LPT) in breast cancers. We have successfully ...developed the lapatinib‐loaded polymer‐lipid hybrid nanosystem and showed its therapeutic potential in in vitro and in vivo models of breast cancer. The nanoformulations consisted of a polymeric core (polylactide‐co‐glycolide‐D‐a‐tocopheryl polyethylene glycol 1000 succinate PLGA–TPGS), which was then enveloped by a PEGylated lipid layer (DSPE‐PEG) (PLPT) to maintain the structural integrity. The PLPT formulation controlled the drug release in pH 7.4 conditions and accelerated the release at pH 5.5 conditions. The PLPT showed a remarkable cellular internalization and efficiently killed the MCF‐7 cancer cells in a time‐ and concentration‐dependent manner. Moreover, LPT‐loaded nanoparticles effectively induced apoptosis of cancer cells than compared to free LPT. Pharmacokinetic data suggested that nanoparticles could significantly enhance the blood circulation time of LPT by reducing the uptake by a reticuloendothelial system (RES). The prolonged blood circulation of PLPT could allow the preferential accumulation of drug in the tumor tissues. Importantly, PLPT significantly reduced the tumor burden of cancerous mice and effectively controlled the tumor cell proliferation. TUNEL assay further showed a greater apoptosis of tumor tissues in the PLPT treated mice group. Our results suggest that the use of a hybrid system may allow a decrease in the dosage regimen without the loss of therapeutic effect. Overall, lapatinib‐loaded hybrid nanoparticles hold great potential for achieving an optimal therapeutic effect in breast cancer treatment. The present anticancer drug delivery system could be potentially applied for the treatment of other cancers.
The present study was performed to investigate the therapeutic performance of polymer‐lipid hybrid nanoparticles towards the delivery of lapatinib (LPT) in breast cancers. We have successfully developed the lapatinib‐loaded polymer‐lipid hybrid nanosystem and showed its therapeutic potential in in vitro and in vivo models of breast cancer.
Insect ryanodine receptors (RyRs) are the targets of diamide insecticides. Two point mutations G4946E and I4790M (numbering according to Plutella xylostella, PxRyR) in the transmembrane domain of the ...insect RyRs associated with diamide resistance have so far been identified in three lepidopteran pests, P. xylostella, Tuta absoluta and Chilo suppressalis. In this study, we identified one of the known RyR target site resistance mutations (I4790M) in a field‐collected population of Spodoptera exigua. The field‐collected WF population of S. exigua exhibited 154 fold resistance to chlorantraniliprole when compared with the susceptible WH‐S strain. Sequencing the transmembrane domains of S. exigua RyR (SeRyR) revealed that the resistant WF strain was homozygous for the I4743M mutation (corresponding to I4790M in PxRyR), whereas the G4900E allele (corresponding to G4946E of PxRyR) was not detected. The 4743M allele was introgressed into the susceptible WH‐S strain by crossing WF with WH‐S, followed by three rounds of backcrossing with WH‐S. The introgressed strain 4743M was homozygous for the mutant 4743M allele and shared about 94% of its genetic background with that of the recipient WH‐S strain. Compared with WH‐S, the near‐isogenic 4743M strain showed moderate levels of resistance to chlorantraniliprole (21 fold), cyantraniliprole (25 fold) and flubendiamide (22 fold), suggesting that the I4743M mutation confers medium levels of resistance to all three diamides. Genetic analysis showed diamide resistance in the 4743M strain was inherited as an autosomal and recessive trait. Results from this study have direct implications for the design of appropriate resistance monitoring and management practices to sustainably control S. exigua.
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