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1.
Proc Natl Acad Sci U S A ; 119(32): e2202767119, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914136

RESUMO

Flash drought often leads to devastating effects in multiple sectors and presents a unique challenge for drought early warning due to its sudden onset and rapid intensification. Existing drought monitoring and early warning systems are based on various hydrometeorological variables reaching thresholds of unusually low water content. Here, we propose a flash drought early warning approach based on spaceborne measurements of solar-induced chlorophyll fluorescence (SIF), a proxy of photosynthesis that captures plant response to multiple environmental stressors. Instead of negative SIF anomalies, we focus on the subseasonal trajectory of SIF and consider slower-than-usual increase or faster-than-usual decrease of SIF as an early warning for flash drought onset. To quantify the deviation of SIF trajectory from the climatological norm, we adopt existing formulas for a rapid change index (RCI) and apply the RCI analysis to spatially downscaled 8-d SIF data from GOME-2 during 2007-2018. Using two well-known flash drought events identified by the operational US Drought Monitor (in 2012 and 2017), we show that SIF RCI can produce strong predictive signals of flash drought onset with a lead time of 2 wk to 2 mo and can also predict drought recovery with several weeks of lead time. While SIF RCI shows great early warning potential, its magnitude diminishes after drought onset and therefore cannot reflect the current drought intensity. With its long lead time and direct relevance for agriculture, SIF RCI can support a global early warning system for flash drought and is especially useful over regions with sparse hydrometeorological data.


Assuntos
Clorofila , Secas , Fluorescência , Previsões , Clorofila/química , Clorofila/metabolismo , Clorofila/efeitos da radiação , Previsões/métodos , Hidrologia , Meteorologia , Fotossíntese , Luz Solar , Estados Unidos
2.
BMC Neurol ; 23(1): 60, 2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36739373

RESUMO

BACKGROUND: Anxiety disorder is a common non-motor symptom among individuals with Parkinson's disease (PD). At present, there are no specific tools in China for assessing the anxiety level of patients with PD. This study aimed to test the reliability and validity of the Chinese version of the Parkinson Anxiety Scale (C-PAS) in Chinese patients with PD. METHODS: A total of 158 patients with PD at one hospital in Nanjing were recruited through convenience sampling. The C-PAS was translated into Chinese using a classic 'forward-backward' translation method. Reliability tests included internal consistency and test-reliability. And in addition to content, structure and criterion-related validity were performed for the validity tests. Criterion-related validity was evaluated with the Hospital Anxiety and Depression Scale-Anxiety Subscale (HADS-A). RESULTS: Results confirmed the three-factor structure of the original C-PAS with 12 items, including persistent anxiety (5 items), episodic anxiety (4 items) and avoidance behavior (3 items). Significant and positive correlations were obtained between C-PAS and HADS-A (r = 0.82, P<0.01). The Cronbach's α and test-retest reliability of the total scale were 0.89 and 0.84, respectively. CONCLUSION: The C-PAS has demonstrated good psychometric properties. Therefore, it can be employed in patients with PD to evaluate the condition of anxiety.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico , Psicometria/métodos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Ansiedade/diagnóstico , Ansiedade/etiologia , China/epidemiologia
3.
Int J Biometeorol ; 64(5): 765-777, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31955263

RESUMO

Net primary productivity (NPP) is an index of the increase in plant biomass. Plant biomass is an important component of the global carbon cycle that indicates the health of an ecosystem. Environmental restoration has recently received much attention in Xinjiang, and it is thus important to quantify the dynamic effects of the drivers of NPP in the region. NPP was calculated for the annual growing season from 1982 to 2013 using the Carnegie-Ames-Stanford Approach (CASA) model. The effects of climate factors on NPP were analyzed, and the relationships between NPP and climate factors as well as human activity were quantified. Additionally, an innovative method based on partial derivatives and residual error was proposed to calculate the contributions of climate factors and human activities. The results show that average annual NPP in Xinjiang was 57.45 g C m-2 from 1982 to 2013 and that the average increase in annual NPP was 0.23 g C m-2 year-1. The average increases in annual NPP due to temperature, precipitation, and solar radiation were 0.0095, 0.2679, and 0.2541 g C m-2 year-1; the average decreases were respectively - 0.0133, - 0.0521, and - 0.0725 g C m-2 year-1. Precipitation and solar radiation influence NPP more than temperature. Precipitation had the greatest effect on NPP in the first 19 years, but solar radiation became more influential after 2000. Climate conditions were favorable for increase in NPP before 2000. The environmental restoration also occurred in Xinjiang during that period, and human activity slightly decreased NPP. Human activity increased and had a greater effect on NPP after 2000.


Assuntos
Ecossistema , Modelos Teóricos , China , Clima , Mudança Climática , Atividades Humanas , Humanos
4.
Int J Biometeorol ; 62(12): 2197-2204, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30368677

RESUMO

Understanding the impacts of climate change on crop yield is important for improving crop growth and yield formation in northwestern China. In this study, we evaluated the relationship between meteorological dryness/wetness conditions and spring wheat yield in the Ili river basin (IRB). The climate and yield data from 1961 to 2013 were collected to analyze characteristics and correlations between these two variables using the standardized precipitation evapotranspiration index (SPEI), yield detrending method, modified Mann-Kendall test and Spearman correlation analysis. Main results were as follows: (1) correlations between monthly SPEI values (MSV) and climatic yield of spring wheat indicated that the dryness/wetness condition in May was a key factor affecting yield in the whole region; (2) although the MSV in May and yield fluctuated from negative to positive values in time, the severely and extremely dryness events were in good agreement with the higher yield losses; (3) each increase of 0.5 MSV in May promoted over 3% increase of yield in most part of IRB; however, the larger variability of MSV in May resulted in larger yield fluctuations; and (4) the Tibetan Plateau index in April showed significant correlations with the MSV in May and yield, which provided a precursory signal for decision-makers to better understand potential yield fluctuations.


Assuntos
Conceitos Meteorológicos , Triticum/crescimento & desenvolvimento , China , Estações do Ano
5.
Front Robot AI ; 11: 1296706, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357294

RESUMO

To effectively control a robot's motion, it is common to employ a simplified model that approximates the robot's dynamics. Nevertheless, discrepancies between the actual mechanical properties of the robot and the simplified model can result in motion failures. To address this issue, this study introduces a pneumatic-driven bipedal musculoskeletal robot designed to closely match the mechanical characteristics of a simplified spring-loaded inverted pendulum (SLIP) model. The SLIP model is widely utilized in robotics due to its passive stability and dynamic properties resembling human walking patterns. A musculoskeletal bipedal robot was designed and manufactured to concentrate its center of mass within a compact body around the hip joint, featuring low leg inertia in accordance with SLIP model principles. Furthermore, we validated that the robot exhibits similar dynamic characteristics to the SLIP model through a sequential jumping experiment and by comparing its performance to SLIP model simulation.

6.
Foodborne Pathog Dis ; 9(11): 1053-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23134287

RESUMO

Aeromonas veronii (AV) is an important pathogen causing severe diseases in aquaculture. Fifteen A. veronii strains isolated from diseased Trionyx sinensis from four aquafarms was characterized by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), antibiotic susceptibility testing, and identification of virulence factors. A. veronii strains were grouped into nine ERIC types with discriminatory ability (D) of 91.43 based on 90% similarity. The virulence genes were detected for 73% (aer), 80% (ast), 13% (alt), and 40% (act) of the strains, respectively, and five antibiotic resistance patterns with D of 0.829 were observed by antibiotic susceptibility testing. Furthermore, some AV isolates (AV1, AV2, AV3, and AV4) show the same characterization (the same ERIC types, presence of virulence genes in genomes, and antibiotics resistance).


Assuntos
Aeromonas/genética , Antibacterianos/farmacologia , Infecções por Bactérias Gram-Negativas/veterinária , Tartarugas/microbiologia , Fatores de Virulência/genética , Aeromonas/efeitos dos fármacos , Aeromonas/isolamento & purificação , Aeromonas/patogenicidade , Animais , Aquicultura , Proteínas de Bactérias/genética , Impressões Digitais de DNA , DNA Bacteriano/genética , Farmacorresistência Bacteriana , Genótipo , Infecções por Bactérias Gram-Negativas/microbiologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Virulência/genética
7.
Sci Total Environ ; 747: 141537, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-32795808

RESUMO

Extensive research has focused on the response of vegetation to climate change, including potential mechanisms and resulting impacts. Although many studies have explored the relationship between vegetation and climate change in China, research on spatiotemporal distribution changes of climate regimes using natural vegetation as an indicator is still lacking. Further, limited information is available on the response of vegetation to shifts in China's regional climatic zones. In this study, we applied Mann-Kendall, and correlation analysis to examine the variabilities in temperature, precipitation, surface soil water, normalised difference vegetation index (NDVI), and albedo in China from 1982 to 2012. Our results indicate significant shifts in the distribution of Köppen-Geiger climate classes in China from 12.08% to 18.98% between 1983 and 2012 at a significance level of 0.05 (MK). The percentage areas in the arid and continental zones expanded at a rate of 0.004%/y and 0.12%/y, respectively, while the percentage area in the temperate and alpine zones decreased by -0.05%/y and - 0.07%/y. Sensitivity fitting results between simulated and observed changes identified temperature to be a dominant control on the dynamics of temperate (r2 = 0.98) and alpine (r2 = 0.968) zones, while precipitation was the dominant control on the changes of arid (r2 = 0.856) and continental (r2 = 0.815) zones. The response of the NDVI to albedo infers a more pronounced radiative response in temperate (r = -0.82, p < .01) and alpine (r = -0.476, p < .05) compared to arid and continental zones. Furthermore, we identified more pronounced monthly increasing trends in NDVI and soil water, corresponding to weak changes in albedo during vegetation growing periods. Our results suggest that climate zone shifting has considerable impacts on the vegetation in China and will have larger ecological impacts through radiative or non-radiative feedback mechanisms in future warming scenarios.

8.
Int J Biochem Cell Biol ; 44(7): 1166-73, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22531714

RESUMO

In our previous studies, ZKSCAN3 was demonstrated to be over-expressed in invasive colonic tumor cells and their liver metastases, but minimally expressed in adjacent non-transformed tissues. Further preliminary data showed that ZKSCAN3 was expressed in a majority of prostate cancer patient samples, but not in normal prostate tissues. Moreover, the ZKSCAN3 protein is highly expressed in the PC3 prostate cancer cell line, which has high metastatic potential, but little expression was observed in non-metastatic prostate cancer cell lines. Thus, we hypothesized that ZKSCAN3 could participate in tumor metastasis by regulating tumor cell migration. To test this hypothesis, ZKSCAN3 mRNA was knocked down by ZKSCAN3 specific shRNA in PC3 cells and a significant decrease in cell motility was observed. In contrast, when ZKSCAN3 cDNA was overexpressed in PC3 cells, cell detachment was observed and suspension culture induced apoptosis was greatly decreased, suggesting that ZKSCAN3 is able to enhance PC3 cell survival under anoikis stress. Additional wound healing and invasion assays showed that cell migration was enhanced by ZKSCAN3 expression. Interestingly, the ZKSCAN3 gene was amplified in 26% (5/19) of metastatic prostate cancers and 20% (1/5) of lymph node metastases, but there was no amplification found in primary prostate cancers, further supporting the role of ZKSCAN3 in tumor cell migration. In vivo studies using orthotopic tumor models indicated that overexpression of ZKSCAN3 significantly enhanced tumorigenicity. Taken together, we provide evidence that ZKSCAN3, a zinc finger transcription factor, plays a critical role in promoting prostate cancer cell migration.


Assuntos
Movimento Celular/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Fatores de Transcrição/genética , Dedos de Zinco/genética , Animais , Linhagem Celular Tumoral , Células Cultivadas , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Neoplasias da Próstata/patologia , Fatores de Transcrição/deficiência , Fatores de Transcrição/metabolismo , Transfecção
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