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1.
Sci Total Environ ; 926: 171827, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38513860

RESUMO

The incorporation of green manure into cropping systems is a potential strategy for sequestering soil carbon (C), especially in saline-alkali soil. Yet, there are still unknown about the substitution impacts of green manure on nitrogen (N) fertilizer in wheat-green manure multiple cropping system. Herein, a five-year field experiment was performed to determine the impact of three levels of N fertilizer inputs [i.e., N fertilizer reduced by 0 % (100N), 10 % (90 N), and 20 % (80 N)] with aboveground biomass of green manure removal (0GM) and return (100GM) on soil organic carbon (SOC) storage and its primary determinants. The results demonstrated that no significant interaction on SOC storage was detected between green manure and N fertilizer management. 80 N enhanced SOC storage in bulk soil by 7.4 and 13.2 % in 0-20 cm soil depth relative to 100 N and 90 N (p < 0.05). Regardless of N fertilizer levels, compared with 100GM, 0GM increased SOC storage in bulk soil by 14.2-34.6 % in 0-40 cm soil depth (p < 0.05). This was explained by an increase in soil macro-aggregates (>2 and 0.25-2 mm) proportion contributing to SOC physical protection. Meanwhile, the improvement of SOC storage under 0GM was due to the decrease of soil C- and N-acquisition enzyme activities, and microbial resource limitation. Alternatively, the variation partitioning analyses (VPA) results further suggested that C- and N-acquisition enzyme activities, as well as microbial resource limitation were the most important factors for SOC storage. The findings highlighted those biological factors played a dominant role in SOC accumulation compared to physical factors. The aboveground biomass of green manure removal with N fertilizer reduced by 20 % is a viable option to enhance SOC storage in a wheat-green manure multiple cropping system.

2.
Nurs Open ; 11(3): e2123, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38429899

RESUMO

AIM: This study aims to investigate the current status and determinants of humanistic care practice abilities among standardized training nurses in China during the post-COVID-19 era, as well as to propose management strategies. DESIGN: A cross-sectional study. METHODS: Deliberately chosen were 517 standardized training nursing students from a provincial-level training facility in western China. RESULTS: The respondents had a mean ± SD age of 21.23 ± 1.34 years, and 92.0% of them voluntarily opted for the nursing profession. Almost all (99.8%) respondents had at least a college degree. The standardized training nurses scored an average of (130.31 ± 14.18) on humanistic care ability, which was significantly related to some sociodemographic variables. The average scores for the five dimensions of nursing communication ability, psychological adjustment ability, moral and legal application ability, nursing aesthetic ability, and care practice ability were 30.78, 17.61, 32.23, 18 and 31.67, respectively. All these dimensions showed positive correlations with the overall score of humanistic care practice ability.


Assuntos
COVID-19 , Enfermeiras e Enfermeiros , Humanos , Adulto Jovem , Adulto , Estudos Transversais , Humanismo , China
3.
Sensors (Basel) ; 23(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38139546

RESUMO

Although the Lissajous frequency modulated (LFM) mode can improve the long-term and temperature stability of the scale factor (SF) for mode mismatch MEMS gyroscopes, its SF nonlinearity poses a significant limitation for full-scale accuracy maintenance. This paper examines the interaction effects among stiffness coupling, system phase delay, readout demodulation phase shift, and velocity amplitude mismatch within the control process. Based on the completion of frequency difference control and demodulation phase matching, we clarify that the remaining stiffness coupling and residual system phase error are the primary factors influencing SF nonlinearity. Furthermore, SF nonlinearity is reduced through error compensation. On one hand, this paper suppresses stiffness coupling through the observation of the instantaneous frequency difference and the application of the quadrature voltage. On the other hand, system phase error is compensated by observing the amplitude control force and tuning the reference in the Phase-Locked Loops (PLLs). Subsequent simulations of these methods demonstrated a remarkable 97% reduction in SF nonlinearity within the measurement range of ±500°/s. In addition, an observed rule dictates that maintaining a sufficiently large frequency split effectively constrains the SF nonlinearity.

4.
Environ Sci Pollut Res Int ; 30(21): 59632-59644, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37012567

RESUMO

Legume-based crop rotation is conducive to improve soil multifunctionality, but how the legacy effect of previous legumes influenced the rhizosphere  microbial community of the following crops along with growth stages remains unclear. Here, the wheat rhizosphere microbial community was assessed at the regreening and filling stages with four previous legumes (mungbean, adzuki bean, soybean, and peanut), as well as cereal maize as a control. The composition and structure of both bacterial and fungal communities varied dramatically between two growth stages. The differences in fungal community structure among rotation systems were observed at both the regreening and filling stages, while the difference in bacterial community structure among rotation systems was observed only at the filling stage. The complexity and centrality of the microbial network decreased along with crop growth stages. The species associations were strengthened in legume-based rotation systems than in cereal-based rotation system at the filling stage. The abundance of KEGG orthologs (KOs) associated with carbon, nitrogen, phosphorus, and sulfur metabolism of bacterial community decreased from the regreening stage to the filling stage. However, there was no difference in the abundance of KOs among rotation systems. Together, our results showed that plant growth stages had a stronger impact than the legacy effect of rotation systems in shaping the wheat rhizosphere microbial community, and the differences among rotation systems were more obvious at the late growth stage. Such compositional, structural, and functional changes may provide predictable consequences of crop growth and soil nutrient cycling.


Assuntos
Fabaceae , Microbiota , Triticum , Rizosfera , Agricultura/métodos , Solo/química , Grão Comestível , Verduras , Microbiologia do Solo
5.
J Environ Manage ; 336: 117677, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36913855

RESUMO

Nitrous oxide (N2O) emissions from agroecosystems are a major contributor to global warming and stratospheric ozone depletion. However, knowledge concerning the hotspots and hot moments of soil N2O emissions with manure application and irrigation, as well as the underlying mechanisms remain incomplete. Here, a 3-year field experiment was conducted with the combination of fertilization (no fertilizer, F0; 100% chemical fertilizer N, Fc; 50% chemical N + 50% manure N, Fc + m; and 100% manure N, Fm) and irrigation (with irrigation, W1; and without irrigation, W0; at wheat jointing stage) for winter wheat - summer maize cropping system in the North China Plain. Results showed that irrigation did not affect annual N2O emissions of the wheat-maize system. Manure application (Fc + m and Fm) reduced annual N2O emissions by 25-51% compared with Fc, which mainly occurred during 2 weeks after fertilization combined with irrigation (or heavy rainfall). In particular, Fc + m reduced the cumulative N2O emissions during 2 weeks after winter wheat sowing and summer maize top dressing by 0.28 and 0.11 kg ha-1, respectively, compared with Fc. Meanwhile, Fm maintained the grain N yield and Fc + m increased grain N yield by 8% compared with Fc under W1. Overall, Fm maintained the annual grain N yield and lower N2O emissions compared to Fc under W0, and Fc + m increased the annual grain N yield and maintained N2O emissions compared with Fc under W1, respectively. Our results provide scientific support for using manure to minimize N2O emissions while maintaining crop N yield under optimal irrigation to support the green transition in agricultural production.


Assuntos
Triticum , Zea mays , Esterco , Fertilizantes , Agricultura/métodos , Solo , Óxido Nitroso/análise , Grão Comestível/química , China
7.
Front Plant Sci ; 13: 947132, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35837461

RESUMO

Contemporary wisdom suggests that inclusion of legumes into crop rotations benefit subsequent cereal crop yields. To investigate whether this maxim was generically scalable, we contrast summer soybean-winter wheat (SW) with summer maize-winter wheat (MW) rotation systems in an extensive field campaign in the North China Plain (NCP). We identify heretofore unseen interactions between crop rotation, synthetic N fertilizer application, and stored soil water. In the year with typical rainfall, inclusion of soybean within rotation had no effect on wheat ear number and yield, while N fertilization penalized wheat yields by 6-8%, mainly due to lower dry matter accumulation after anthesis. In contrast, in dry years prior crops of soybean reduced the rate and number of effective ears in wheat by 5-27 and 14-17%, respectively, leading to 7-23% reduction in wheat yield. Although N fertilization increased the stem number before anthesis in dry years, there was no corresponding increase in ear number and yield of wheat in such years, indicating compensating reduction in yield components. We also showed that N fertilization increased wheat yield in MW rather than SW as the former better facilitated higher dry matter accumulation after flowering in dry years. Taken together, our results suggest that soybean inclusion reduced soil available water for subsequent wheat growth, causing yield penalty of subsequent wheat under drought conditions. We call for more research into factors influencing crop soil water, including initial state, crop water requirement, and seasonal climate forecasts, when considering legumes into rotation systems. Graphical AbstractResponse of wheat population and yield to soybean inclusion under limited-irrigation.

8.
Environ Sci Pollut Res Int ; 27(8): 8016-8027, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31889290

RESUMO

Methane (CH4) emission is the consequence of CH4 production and consumption performed by methanogens and methanotrophs, respectively. Fertilization is an important factor that regulates the behavior of methanogens and methanotrophs; however, the effect of manure and rice straw addition combined with inorganic fertilizers on these communities is not well understood. This study aimed to explore how manure and rice straw amendments together with inorganic fertilizers influenced the methanogenic and methanotrophic communities in a 31-year fertilized rice paddy. Manure amendment significantly increased the abundance of mcrA and pmoA genes by 61.2% and 63.3% compared with the unfertilized control, whereas inorganic NPK fertilization alone or rice straw addition did not affect their abundances. Manure and rice straw amendments greatly decreased the Shannon index and ACE index of the methanogenic communities, whereas inorganic NPK fertilization alone increased the ACE index of the methanotrophic communities compared with the unfertilized control. Methanosarcinaceae and Methylococcaceae dominated at the family level, representing 23.1-35.0% and 48.7-67.2% of the total reads, for the methanogenic and methanotrophic communities, respectively. Application of manure together with inorganic fertilizers suppressed the Methanocellales methanogens and the type I methanotrophs (Methylococcus and Methylobacter). Fertilization greatly altered the community structure of methanogens and methanotrophs, and manure addition had more apparent effects than rice straw. Moreover, total nitrogen, soil organic carbon, available phosphorus, and available potassium correlated significantly to the abundance, composition, and community structure of methanogens and methanotrophs. In conclusion, our study revealed that long-term manure amendment in combination with inorganic fertilizers significantly increased the abundance of methanogens and methanotrophs, but suppressed the type I methanotrophs in rice paddies.


Assuntos
Carbono/química , Fertilizantes/análise , Metano/química , Methylococcaceae , Oryza , Agricultura , Esterco , Solo
9.
J Environ Sci (China) ; 54: 142-151, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28391923

RESUMO

Rare and consecutive high-nitrate haze pollution episodes were observed in Beijing in spring 2012. We present detailed characterization of the sources and evolutionary mechanisms of this haze pollution, and focus on an episode that occurred between 15 and 26 April. Submicron aerosol species were found to be substantially elevated during haze episodes, and nitrates showed the largest increase and occupation (average: 32.2%) in non-refractory submicron particles (NR-PM1), which did not occur in other seasons as previously reported. The haze episode (HE) was divided into three sub-episodes, HEa, HEb, and HEc. During HEa and HEc, a shallow boundary layer, stagnant meteorological conditions, and high humidity favored the formation of high-nitrate concentrations, which were mainly produced by three different processes - daytime photochemical production, gas-particle partitioning, and nighttime heterogeneous reactions - and the decline in visibility was mainly induced by NR-PM1. However, unlike HEa and HEc, during HEb, the contribution of high nitrates was partly from the transport of haze from the southeast of Beijing - the transport pathway was observed at ~800-1000m by aerosol Lidar - and the decline in visibility during HEb was primarily caused by PM2.5. Our results provide useful information for air quality improvement strategies in Beijing during Spring.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Nitratos/análise , Material Particulado/análise , Pequim , Umidade , Estações do Ano , Tempo (Meteorologia)
10.
J Environ Sci (China) ; 25 Suppl 1: S63-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25078842

RESUMO

The Direct Pink 12B dye was treated by iron-carbon micro-electrolysis (ICME) and Fenton oxidation. The degradation pathway of Direct Pink 12B dye was inferred by ultraviolet visible (UV-Vis), infrared absorption spectrum (IR) and high performance liquid chromatography-mass spectrometry (HPLC-MS). The major reason of decolorization was that the conjugate structure was disrupted in the iron-carbon micro-electrolysis (ICME) process. However, the dye was not degraded completely because benzene rings and naphthalene rings were not broken. In the Fenton oxidation process, the azo bond groups surrounded by higher electron cloud density were first attacked by hydroxyl radicals to decolorize the dye molecule. Finally benzene rings and naphthalene rings were mineralized to H2O and CO2 under the oxidation of hydroxyl radicals.


Assuntos
Compostos Azo/química , Eletrólise , Carbono/química , Cromatografia Líquida de Alta Pressão , Peróxido de Hidrogênio/química , Ferro/química , Espectrometria de Massas , Oxirredução , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Fatores de Tempo
11.
Neurol Res ; 30(7): 731-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18593521

RESUMO

The therapeutic effect of a novel RNA viral vector, Sendai virus (SeV)-mediated glial cell line-derived neurotrophic factor (GDNF) gene (SeV/GDNF), on the infarct volume, was investigated after 90 minutes of transient middle cerebral artery occlusion (tMCAO) in rats with relation to nuclear translocation of apoptosis inducing factor (AIF). The topical administration of SeV/GDNF induced high level expression of GDNF protein, which effectively reduced the infarct volume when administrated 0 and 1 hours as well after the reperfusion. Twenty-four hours after ischemia, the obvious nuclear translocation of AIF was found in neurons of peri-infarct area, which significantly reduced with administration of SeV/GDNF 0 or 1 hour after reperfusion, as well as the number of TUNEL positive cells. These results demonstrate that SeV vector-mediated gene transfer of GDNF effectively reduced ischemic infarct volume after tMCAO and extended the therapeutic time window compared with previous viral vectors, and that promoting neuronal survival of GDNF might be related to the reduction of AIF nuclear translocation, indicating the high therapeutic potency of SeV/GDNF for cerebral ischemia.


Assuntos
Fator de Indução de Apoptose/metabolismo , Técnicas de Transferência de Genes , Terapia Genética/métodos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Hipóxia-Isquemia Encefálica/terapia , Vírus Sendai/genética , Transporte Ativo do Núcleo Celular/genética , Animais , Apoptose/genética , Fator de Indução de Apoptose/genética , Infarto Encefálico/genética , Infarto Encefálico/metabolismo , Infarto Encefálico/terapia , Modelos Animais de Doenças , Vetores Genéticos/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Hipóxia-Isquemia Encefálica/genética , Hipóxia-Isquemia Encefálica/metabolismo , Marcação In Situ das Extremidades Cortadas , Infarto da Artéria Cerebral Média/genética , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/terapia , Masculino , Degeneração Neural/genética , Degeneração Neural/prevenção & controle , Degeneração Neural/terapia , Ratos , Ratos Wistar , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima/genética
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