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1.
Glob Chang Biol ; 30(5): e17309, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38747209

RESUMO

Global soil nitrogen (N) cycling remains poorly understood due to its complex driving mechanisms. Here, we present a comprehensive analysis of global soil δ15N, a stable isotopic signature indicative of the N input-output balance, using a machine-learning approach on 10,676 observations from 2670 sites. Our findings reveal prevalent joint effects of climatic conditions, plant N-use strategies, soil properties, and other natural and anthropogenic forcings on global soil δ15N. The joint effects of multiple drivers govern the latitudinal distribution of soil δ15N, with more rapid N cycling at lower latitudes than at higher latitudes. In contrast to previous climate-focused models, our data-driven model more accurately simulates spatial changes in global soil δ15N, highlighting the need to consider the joint effects of multiple drivers to estimate the Earth's N budget. These insights contribute to the reconciliation of discordances among empirical, theoretical, and modeling studies on soil N cycling, as well as sustainable N management.


Assuntos
Ciclo do Nitrogênio , Solo , Solo/química , Isótopos de Nitrogênio/análise , Aprendizado de Máquina , Nitrogênio/análise , Nitrogênio/metabolismo , Clima , Modelos Teóricos
2.
Medicine (Baltimore) ; 103(15): e37582, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608063

RESUMO

BACKGROUND: Atrial fibrillation (AF) is one of the most common clinical arrhythmias. This study aims to predict the risk of post-stroke AF through electrocardiographic changes in sinus rhythm. METHODS: We searched the MEDLINE (PubMed) and EMBASE databases to identify relevant research articles published until August 2023. Prioritized items from systematic reviews and meta-analyses were screened, and data related to AF detection rate were extracted. A meta-analysis using a random-effects model was conducted for data synthesis and analysis. RESULTS: A total of 32 studies involving electrocardiograms (ECG) were included, with a total analysis population of 330,284 individuals. Among them, 16,662 individuals (ECG abnormal group) developed AF, while 313,622 individuals (ECG normal group) did not. ECG patterns included terminal P-wave terminal force V1, interatrial block (IAB), advanced interatrial block, abnormal P-wave axis, pulse rate prolongation, and atrial premature complexes. Overall, 15,762 patients experienced AF during the study period (4.77%). In the ECG abnormal group, the proportion was 14.21% (2367/16,662), while in the control group (ECG normal group), the proportion was 4.27% (13,395/313,622). The pooled risk ratio for developing AF was 2.45 (95% confidence interval [CI]: 2.02-2.98, P < .001), with heterogeneity (I2) of 95%. The risk ratio values of alAB, P-wave terminal force V1, interatrial block, abnormal P-wave axis, pulse rate prolongation and atrial premature complexes were 4.12 (95% CI, 2.99-5.66), 1.47 (95% CI, 1.19-1.82), 2.54 (95% CI, 1.83-3.52), 1.70 (95% CI, 0.98-2.97), 2.65 (95% CI, 1.88-3.72), 3.79 (95% CI, 2.12-6.76), respectively. CONCLUSION: There is a significant correlation between ECG patterns and the occurrence of AF. The alAB exhibited the highest level of predictability for the occurrence of AF. These indicators support their use as screening tools to identify high-risk individuals who may benefit from further examinations or empirical anticoagulation therapy following stroke.


Assuntos
Fibrilação Atrial , Complexos Atriais Prematuros , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Bloqueio Interatrial , Revisões Sistemáticas como Assunto , Metanálise como Assunto , Frequência Cardíaca , Eletrocardiografia
3.
AIDS Care ; : 1-9, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526977

RESUMO

Mental health problems leads to serious disease burden among people living with HIV/AIDS (PLHIV). The study aimed at measuring the mental disorders-caused burden of disease based on PLHIV in mainland China. The data used was from the national HIV/AIDS case reporting system, life expectancy (LE) and LE-eliminated suicide were evaluated by the life-table method. The total YLLs and YLLs caused by suicide in each age group were calculated. The disability weights were estimated by the scale of depression symptoms (CES-D) from the multi-center cross-sectional survey, then calculated the corresponding YLDs as a burden of mental illness among PLHIV. Results showed that the LE had been prolonged by implementing antiviral therapy for PLHIV. The proportion of YLLs caused by suicide was the highest (5·46%) in the 15-24 age group. The YLDs in the 25-34 age group were the highest. The YLLs caused by suicide in males were higher than those in the same age group of females. The YLDs and YLLs were higher in heterosexual-infected PLHIV than in homosexual-infected PLHIV, except for YLLs in the 25-34 age group. In summary, this study first provided localized data on the disease burden caused by mental health problems among PLHIV.

4.
J Biochem Mol Toxicol ; 38(4): e23685, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38495002

RESUMO

Neurodegeneration is linked to the progressive loss of neural function and is associated with several diseases. Hypoxia is a hallmark in many of these diseases, and several therapies have been developed to treat this disease, including gene expression therapies that should be tightly controlled to avoid side effects. Cells experiencing hypoxia undergo a series of physiological responses that are induced by the activation of various transcription factors. Modulation of microRNA (miRNA) expression to alter transcriptional regulation has been demonstrated to be beneficial in treating multiple diseases, and in this study, we therefore explored potential miRNA candidates that could influence hypoxia-induced nerve cell death. Our data suggest that in mouse neuroblasts Neuro-2a cells with hypoxia/reoxygenation (H/R), miR-337-3p is downregulated to increase the expression of Potassium channel tetramerization domain containing 11 (KCTD11) and subsequently promote apoptosis. Here, we demonstrate for the first time that KCTD11 plays a role in the cellular response to hypoxia, and we also provide a possible regulatory mechanism by identifying the axis of miR-337-3p/KCTD11 as a promising candidate modulator of nerve cell survival after H/R exposure.


Assuntos
MicroRNAs , Neuroblastoma , Animais , Camundongos , Regulação para Baixo , Regulação da Expressão Gênica , Hipóxia/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Neuroblastoma/genética
5.
Nat Commun ; 15(1): 2668, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38531906

RESUMO

International initiatives set ambitious targets for ecological restoration, which is considered a promising greenhouse gas mitigation strategy. Here, we conduct a meta-analysis to quantify the impacts of ecological restoration on greenhouse gas emissions using a dataset compiled from 253 articles. Our findings reveal that forest and grassland restoration increase CH4 uptake by 90.0% and 30.8%, respectively, mainly due to changes in soil properties. Conversely, wetland restoration increases CH4 emissions by 544.4%, primarily attributable to elevated water table depth. Forest and grassland restoration have no significant effect on N2O emissions, while wetland restoration reduces N2O emissions by 68.6%. Wetland restoration enhances net CO2 uptake, and the transition from net CO2 sources to net sinks takes approximately 4 years following restoration. The net ecosystem CO2 exchange of the restored forests decreases with restoration age, and the transition from net CO2 sources to net sinks takes about 3-5 years for afforestation and reforestation sites, and 6-13 years for clear-cutting and post-fire sites. Overall, forest, grassland and wetland restoration decrease the global warming potentials by 327.7%, 157.7% and 62.0% compared with their paired control ecosystems, respectively. Our findings suggest that afforestation, reforestation, rewetting drained wetlands, and restoring degraded grasslands through grazing exclusion, reducing grazing intensity, or converting croplands to grasslands can effectively mitigate greenhouse gas emissions.

6.
Mikrochim Acta ; 191(4): 218, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530416

RESUMO

An electrochemical sensor for detecting ketoprofen was constructed by in-situ grown copper cobaltate (CuCo2O4) nanoneedle arrays on a carbon cloth (CC) substrate. The resulting porous nanoneedle arrays not only expose numerous electrochemically active sites but also significantly enhance the electrochemical apparent active area and current transmission efficiency. By leveraging its electrochemical properties, the sensor achieves an impressive detection limit for ketoprofen of 0.7 pM, with a linear range spanning from 2 pM ~ 2 µM. Furthermore, the sensor exhibits remarkable reproducibility, anti-interference capabilities, and stability. Notably, the developed sensor also performed ketoprofen detection on real samples (including drug formulations and wastewater) and demonstrated excellent recognition ability. These exceptional performances can be attributed to the direct growth of CuCo2O4 nanoneedle arrays on the CC substrate, which facilitates a robust electrical connection, provides abundant electrocatalytic active sites, and expands the apparent active area. Consequently, these improvements contribute to the efficient trace detection capabilities of the ketoprofen sensor.

7.
ACS Sens ; 9(3): 1391-1400, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38364864

RESUMO

Achieving reliable detection of trace levels of NO2 gas is essential for environmental monitoring and protection of human health protection. Herein, a thin-film gas sensor based on branched WO3/W18O49 heterostructures was fabricated. The optimized WO3/W18O49 sensor exhibited outstanding NO2 sensing properties with an ultrahigh response value (1038) and low detection limit (10 ppb) at 50 °C. Such excellent sensing performance could be ascribed to the synergistic effect of accelerated charge transfer and increased active sites, which is confirmed by electrochemical impedance spectroscopy and temperature-programmed desorption characterization. The sensor exhibited an excellent detection ability to NO2 under different air quality conditions. This work provides an effective strategy for constructing WO3/W18O49 heterostructures for developing NO2 gas sensors with an excellent sensing performance.


Assuntos
Espectroscopia Dielétrica , Dióxido de Nitrogênio , Humanos , Domínio Catalítico , Monitoramento Ambiental
8.
Sci Total Environ ; 917: 170416, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38281651

RESUMO

Diversity and biomass play an important role in grassland ecosystem functions. However, diversity and biomass are variable because of their high sensitivity to environmental change in natural ecosystems. How plant diversity, biomass, and driving factors (climates, soils, and plants) in grasslands vary with environmental change remains unclear. We conducted intensive fieldwork (≈1000 km transect) on plant diversity, biomass, and associated drivers (i.e., climates, soils, and plants) to identify the patterns of diversity and biomass along an elevational gradient (50-4000 m) in grasslands of southwest China. Grassland biomass decreased significantly, but grassland diversity increased with increasing elevation. Consequently, a significant reverse pattern between biomass and diversity was detected along an elevational gradient. We also observed that the reverse pattern was primarily driven by the shifts in climates (i.e., temperature and precipitation), leaf stoichiometric traits (i.e., leaf N:P ratio), and soil properties (i.e., soil N content) along the elevational gradient. Our results contradicted previous studies on the positive diversity-biomass relationships, suggesting that previous studies might weaken the effects of climatic factors and plant stoichiometry under environmental change. These findings revealed that the reverse pattern between diversity and biomass in grasslands was shaped by the combined effects (climates, plants, soils) in grasslands, thus providing new insights into the debates and predictions on the diversity and biomass in grasslands under climate change.


Assuntos
Ecossistema , Pradaria , Biomassa , Solo , China , Plantas
9.
Glob Chang Biol ; 30(1): e16989, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37888833

RESUMO

Anthropogenic nitrogen (N) loading alters soil ammonia-oxidizing archaea (AOA) and bacteria (AOB) abundances, likely leading to substantial changes in soil nitrification. However, the factors and mechanisms determining the responses of soil AOA:AOB and nitrification to N loading are still unclear, making it difficult to predict future changes in soil nitrification. Herein, we synthesize 68 field studies around the world to evaluate the impacts of N loading on soil ammonia oxidizers and nitrification. Across a wide range of biotic and abiotic factors, climate is the most important driver of the responses of AOA:AOB to N loading. Climate does not directly affect the N-stimulation of nitrification, but does so via climate-related shifts in AOA:AOB. Specifically, climate modulates the responses of AOA:AOB to N loading by affecting soil pH, N-availability and moisture. AOB play a dominant role in affecting nitrification in dry climates, while the impacts from AOA can exceed AOB in humid climates. Together, these results suggest that climate-related shifts in soil ammonia-oxidizing community maintain the N-stimulation of nitrification, highlighting the importance of microbial community composition in mediating the responses of the soil N cycle to N loading.


Assuntos
Amônia , Solo , Solo/química , Nitrificação , Nitrogênio/análise , Oxirredução , Microbiologia do Solo , Archaea , Filogenia
10.
Front Psychiatry ; 14: 1287217, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38076705

RESUMO

Introduction: As a common phenomenon of workplace negative gossip in organizations, how it affects employees' work engagement is not yet clear, nor what methods can be used to mitigate its negative impact on employees' work engagement. Methods: Based on Conservation of Resource Theory, this study obtained 334 valid employee samples from mainland China enterprises through a three-time lagged research design and explored the mechanism of negative workplace gossip on work engagement from the dual perspectives of employees and supervisors. Results: The results show that: (1) Negative workplace gossip negatively affects employee work engagement. (2) Professional commitment plays a mediating role between negative workplace gossip and employee work engagement. (3) Employee mindfulness negatively moderates the negative impact of workplace negative gossip on professional commitment; superior trust negatively moderates the negative impact of workplace negative gossip on professional commitment. (4) Employee mindfulness and superior trust are further weakened to moderate the negative indirect impact of workplace negative gossip on employee work engagement through professional commitment, and this negative indirect impact is weaker when employees have a higher degree of mindfulness and higher trust in superiors. Discussion: It proposes effective strategies for managing workplace gossip to harness its positive influence and offer practical guidance to enhance employee work engagement.

11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(12): 1512-1516, 2023 Dec 10.
Artigo em Chinês | MEDLINE | ID: mdl-37994133

RESUMO

OBJECTIVE: To analyze the clinical phenotypes and genetic variants of a Chinese pedigree affected with Hereditary coagulation factor Ⅻ (FⅫ) deficiency. METHODS: A pedigree presented at the First Affiliated Hospital of Air Force Medical University on December 24,2021 was selected as the study subject. Activated partial thromboplastin time (APTT) and coagulation factor Ⅻ activity (FⅫ:C) were determine by a clotting method, and FⅫ antigen was detected with an ELISA assay. Following the extraction of genomic DNA, all exons and flanking regions of the F12 gene were subjected to Sanger sequencing. Clustalx-2.1-win, PROVEAN and Swiss-PDB Viewer software was used to analyze the conservation of amino acids at the variant sites, impact of of the variants on the amino acid substitutions and the protein structure. RESULTS: The APTT of the proband has prolonged to 70.2 s. Her FⅫ:C and FⅫ:Ag have decreased to 12% and 13%, respectively. DNA sequencing revealed that the proband has harbored c.346G>A (p.Gly97Ser) and c.1583C>A (p.Ser509Tyr) heterozygous compound missense variants in exons 5 and 13 of the F12 gene, respectively. Her father and sister were heterozygous carriers for the c.346G>A (p.Gly97Ser) variant, whilst her mother and brother were heterozygous for the c.1583C>A (p.Ser509Tyr) variant. CONCLUSION: The c.346G>A (p.Gly97Ser) and c.1583C>A (p.Ser509Tyr) compound heterozygous variants of the F12 gene probably underlay the pathogenesis of hereditary coagulation FⅫ deficiency in this pedigree.


Assuntos
Deficiência do Fator XII , Fator XII , Humanos , Masculino , Feminino , Linhagem , Fator XII/genética , Mutação , População do Leste Asiático , Heterozigoto , Mães , Deficiência do Fator XII/genética
12.
Chemosphere ; 341: 140067, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37673187

RESUMO

Afforestation is increasingly important in nutrient cycling in riparian ecotones given that ecosystems in riparian zones are susceptible to anthropogenic activities induced by land use change. However, how land use change (e.g., afforestation) with different planting types influences nitrogen (N) dynamics in riparian zones remains unclear. Here, we examined soil N dynamics following afforestation with three types of plantations of pure willow (Salix babylonica), pure mulberry (Morus alba), and the mixed two species paired with adjacent maize croplands in the upper Yangtze River of China. Our results showed afforestation with the two pure species significantly reduced soil total N (TN) concentration. Soil NO3--N concentration was significantly reduced by the willow and mixed-species afforestation, but soil NH4+-N concentration was significantly higher in the willow and mixed woodlands compared to the paired croplands. Soil N concentrations were tightly associated with the potential N transformation rates, which showed a roughly decreasing trend in N mineralization following afforestation. Soil properties, microbial biomass, and extracellular enzymes jointly explained a large proportion of the total variation in soil N concentrations, with soil enzymes largely contributing to N variation in the topsoil and soil properties primarily contributing to N variation in the subsoil. Overall, our results demonstrate that afforestation with different planting types had contrasting effects on soil N content in the riparian zone. These findings provide new insights into the management of afforestation types to retain soil N by mediating soil properties and microbial activities in the riparian zones under future land use change.


Assuntos
Ecossistema , Salix , Rios , China , Nitrogênio , Solo
13.
ACS Sens ; 8(10): 3723-3732, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37610721

RESUMO

Glutaraldehyde disinfectant has been widely applied in aquaculture, farming, and medical treatment. Excessive concentrations of glutaraldehyde in the environment can lead to serious health hazards. Therefore, it is extremely important to develop high-performance glutaraldehyde sensors with low cost, high sensitivity, rapid response, fabulous selectivity, and low limit of detection. Herein, mesoporous lanthanum (La) doped SnO2 spheres with high specific surface area (52-59 m2 g-1), uniform mesopores (with a pore size concentrated at 5.7 nm), and highly crystalline frameworks are designed to fabricate highly sensitive gas sensors toward gaseous glutaraldehyde. The mesoporous lanthanum-doped SnO2 spheres exhibit excellent glutaraldehyde-sensing performance, including high response (13.5@10 ppm), rapid response time (28 s), and extremely low detection limit of 0.16 ppm. The excellent sensing performance is ascribed to the high specific surface area, high contents of chemisorbed oxygen species, and lanthanum doping. DFT calculations suggest that lanthanum doping in the SnO2 lattice can effectively improve the adsorption energy toward glutaraldehyde compared to pure SnO2 materials. Moreover, the fabricated gas sensors can effectively detect commercial glutaraldehyde disinfectants, indicating a potential application in aquaculture, farming, and medical treatment.


Assuntos
Desinfetantes , Glutaral , Lantânio , Agricultura , Adsorção , Gases
14.
Glob Chang Biol ; 29(17): 4697-4699, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37430461

RESUMO

A conceptual framework proposes that soil N2 O emissions are more likely related to microbial functional gene abundances based on laboratory experiments than in-situ observations. This framework has largely contributed to reconciling the disputation on linking soil N2 O emissions with functional gene abundances, but the direct evidence is lacking. Wei et al. (2023) provided new evidence to support this framework, showing that O2 dynamics were a better predictor of in-situ soil N2 O emissions than were functional gene abundances. Before the observations can inform N2 O modeling and support sustainable nitrogen management, however, some additional efforts are needed to revisit the relationships between in-situ soil N2 O emissions and functional gene abundances.


Assuntos
Óxido Nitroso , Solo , Óxido Nitroso/análise , Nitrogênio/análise
15.
Biomater Res ; 27(1): 63, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37391845

RESUMO

BACKGROUND: Ferroptosis, iron-dependent cell death, is an established mechanism for cancer suppression, particularly in hepatocellular carcinoma (HCC). Sorafenib (SOR), a frontline drug for the treatment of HCC, induces ferroptosis by inhibiting the Solute Carrier family 7 member 11 (SLC7A11), with inadequate ferroptosis notably contributing to SOR resistance in tumor cells. METHODS: To further verify the biological targets associated with ferroptosis in HCC, an analysis of the Cancer Genome Atlas (TCGA) database was performed to find a significant co-upregulation of SLC7A11 and transferrin receptor (TFRC), Herein, cell membrane-derived transferrin nanovesicles (TF NVs) coupled with Fe3+ and encapsulated SOR (SOR@TF-Fe3+ NVs) were established to synergistically promote ferroptosis, which promoted the iron transport metabolism by TFRC/TF-Fe3+ and enhanced SOR efficacy by inhibiting the SLC7A11. RESULTS: In vivo and in vitro experiments revealed that SOR@TF-Fe3+ NVs predominantly accumulate in the liver, and specifically targeted HCC cells overexpressing TFRC. Various tests demonstrated SOR@TF-Fe3+ NVs accelerated Fe3+ absorption and transformation in HCC cells. Importantly, SOR@TF-Fe3+ NVs were more effective in promoting the accumulation of lipid peroxides (LPO), inhibiting tumor proliferation, and prolonging survival rates in HCC mouse model than SOR and TF- Fe3+ NVs alone. CONCLUSIONS: The present work provides a promising therapeutic strategy for the targeted treatment of HCC.

16.
Front Vet Sci ; 10: 1064522, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846263

RESUMO

Pathogenic bacteria were isolated from the uterine lavage fluid of a mare with endometritis. After identification and purification, the pathogenic bacteria were injected into the uterus of rabbits to induce endometritis. Then, anatomical, blood routine, chemical examination, and histopathological examinations were performed on the rabbits. Rabbit uterus was collected, and quantitative polymerase chain reaction (qPCR) was used to detect the mRNA expression of inflammatory factors including IL-1ß, IL-6, and TNF-α in the rabbit uterus. In addition, enzyme-linked immunosorbent assay (ELISA) was used to detect the uterine concentrations of the inflammatory factors IL-1ß, IL-6, and TNF-α. Western Blot was used to detect the protein expressions of NF-kB, IkBα, and TNF-α in the NF-kB pathway. An antibiotic treatment group was also set up to verify the accuracy of the results. The clinical examination results showed that there was a significant increase of leukocytes in the blood of the rabbits in the model group (P < 0.01). The uterus was congested, enlarged, and purulent. The integrity of the uterine lining was destroyed, and there was a significant increase of lymphocytes in the uterus (P < 0.01). The qPCR and ELISA results showed that the expressions of the inflammatory factors IL-1ß, IL-6, and TNF-α in the uterus of rabbits were significantly increased (P < 0.01). Western blot results showed that the inflammatory factors IL-1ß, IL-6, and TNF-α play a role in promoting inflammation through the NF-kB pathway. The results of the test provide a simple, economical, and reliable means of studying the occurrence, development, prevention, and treatment of equine endometritis.

17.
Phys Chem Chem Phys ; 25(3): 2430-2438, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36598374

RESUMO

Searching for high-performance anode materials and CO2 adsorption materials are key factors for next-generation renewable energy technologies and mitigation of the greenhouse effect. Herein, we report a novel two-dimensional (2D) BC2P monolayer with great potential as an anode material for lithium-ion batteries (LIBs) and as a material for CO2 adsorption. The adsorption energies of Li atoms and CO2 molecules on the BC2P supercell are negative enough to assure stability and safety under operating conditions. More intriguingly, the BC2P monolayer possesses a very high theoretical capacity of 1018.8 mA g h-1 for LIBs. In addition, the diffusion energy barriers of Li on the BC2P supercell are 0.26 and 0.87 eV, showing good charge/discharge capability, and the electrode potential of Li is beneficial to their performance as an anode material. Moreover, four chemical and three physical adsorption sites were verified, indicating that the CO2 molecule was effectively adsorbed on the BC2P supercell. These desirable properties make the BC2P monolayer a promising 2D material for application in LIBs and for CO2 adsorbents aimed at highly efficient CO2 capture.

18.
Chemosphere ; 313: 137452, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36481173

RESUMO

Soil phosphorus (P) is an essential nutrient element for plant growth but it is also one of the elements of agricultural-dominated watershed pollution. While the vegetation in the riparian zone usually plays an important role in regulating P pollutants. However, how afforestation affects soil P dynamics and fractions in the riparian zone remains largely unclear. Here, we investigated soil P fractions, and associated drivers including edaphic properties, microbial attributes, and soil enzyme activities under conversion from cropland to different afforested lands in order to better understand the dynamics of soil P fractions in the riparian zone of the upper Yangtze River. We found that afforestation significantly decreased the concentrations of available phosphorus, microbial biomass P, and labile P fractions, but the moderately labile P and Stable P did not significantly differ among afforestation types. Particularly, the lowest concentration of labile P was observed in Morus alba (M.a.) forests followed by the Salix babylonica (S.b.) forests, whereas croplands generally exhibited an inverse trend with a higher labile P concentration compared to woodlands, especially in croplands nearby Morus alba forests. Generally, P fractions were negatively associated with soil pH and C:N ratio, while positively related to microbial attributes, N:P ratio, and alkaline phosphatase activities. The labile P and moderately labile P fractions were predominantly regulated by biotic factors (i.e., microbial biomass P, microbial biomass N, leucine amino peptidase), whereas the stable P was strongly related to abiotic factors (i.e., total C concentration, pH, C:N ratio). These findings indicate afforestation is conducive to intercept more labile P, resulting in reduced P leaching to rivers. Collectively, our results not only offer direct experimental insight into predicting the effects of afforestation on soil P fractions but also have important implications for agricultural pollution management and reforestation strategies in the riparian zone.


Assuntos
Monitoramento Ambiental , Solo , Solo/química , Fósforo/análise , Rios , Florestas , China , Nitrogênio/análise
19.
Br J Nutr ; 130(2): 185-201, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35508921

RESUMO

To assess the role of dietary creatine on myofibre characteristics and protein synthesis in muscle, we fed grass carp (Ctenopharyngodon idellus, initial body weight: 88·47 ± 1·44 g) creatine-supplemented diets (1·84, 5·91, 8·48 and 15·44 g/kg diet) for 8 weeks. Creatine supplementation did not affect growth performance, but significantly increased creatine contents in muscle and liver. At 8·48 g/kg, creatine decreased the activities of alanine transaminase and aspartate aminotransferase in serum and improved hardness and chewiness of muscle due to shorter myofibre mean diameter, higher myofibre density and the frequencies of the diameters of classes I and III and collagen content, longer sarcomere length and upregulated mRNA levels of slow myosin heavy chains. Creatine supplementation upregulated the mRNA expressions of myogenic regulatory factors. The 8·48 g/kg creatine-supplemented diet significantly increased the contents of protein, total amino acids (AA), essential AA and free flavour AAs in muscle, the protein levels of insulin-like growth factor I, myogenic differentiation antigen and PPAR-γ coactlvator-1α in muscle and stimulated the phosphorylation of target of rapamycin (TOR) pathway in muscle. In summary, 8·48 mg/kg creatine improved fish health and skeletal muscle growth and increased hardness and protein synthesis in muscle of grass carp by affecting myofibre characteristics and the TOR signalling pathway. A second-order regression model revealed that the optimal dietary creatine supplementation of grass carp ranges between 8·48 and 12·04 g/kg.


Assuntos
Carpas , Suplementos Nutricionais , Animais , Creatina , Proteínas Musculares , Carpas/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Dieta , RNA Mensageiro/metabolismo , Músculos/metabolismo , Ração Animal/análise
20.
J Hazard Mater ; 442: 130041, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36166911

RESUMO

In recent years, carbon monoxide (CO) intoxication incidents occur frequently, and the sensitive detection of CO is particularly significant. At present, most reported carbon monoxide (CO) sensors meet the disadvantage of high working temperature. It is always a challenge to realize the sensitive detection of carbon monoxide at room temperature. In this study, CuO nanosheets exposed more (111) active crystal facets and oxygen vacancy defects were synthesized by a simple and environmentally friendly one-step hydrothermal method. The sensor has good comprehensive gas sensing performance, compared with other sensors that can detect CO at room temperature. The response value to 100 ppm CO at room temperature is as high as 39.6. In addition, it also has excellent selectivity, low detection limit (100 ppb), good reproducibility, moisture resistance and long-term stability (60 days). This excellent gas sensing performance is attributed to the special structural characteristics of 2D materials and the synergistic effect of more active crystal facets exposed on the crystal surface and oxygen vacancy defects. Therefore, it is expected to become a promising sensitive material for rapid and accurate detection of trace CO gas under low energy consumption, reduce the risk of poisoning, and then effectively protect human life safety.


Assuntos
Monóxido de Carbono , Oxigênio , Humanos , Temperatura , Reprodutibilidade dos Testes , Oxigênio/química
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