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1.
Molecules ; 29(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38675545

RESUMO

The use of surfactants in oil recovery can effectively improve crude oil recovery rate. Due to the enhanced salt and temperature resistance of surfactant molecules by non-ionic chain segments, anionic groups have good emulsifying stability. Currently, there are many studies on anionic non-ionic surfactants for oil recovery in China, but there is relatively little systematic research on introducing EOs into hydrophobic alkyl chains, especially on their self-assembly behavior. This article proposes a simple and effective synthesis method, using 3-aminopropane sulfonic acid, fatty alcohol polyoxyethylene ether, and epichlorohydrin as raw materials, to insert EO into hydrophobic alkyl chains and synthesize a series of new anionic non-ionic Gemini surfactants (CnEO-5, n = 8, 12, 16). The surface activity, thermodynamic properties, and self-assembly behavior of these surfactants were systematically studied through surface tension, conductivity, steady-state fluorescence probes, transmission electron microscopy, and molecular dynamics simulations. The surface tension test results show that CnEO-5 has high surface activity and is higher than traditional single chain surfactants and structurally similar anionic non-ionic Gemini surfactants. Additionally, thermodynamic parameters (e.g., ΔG°mic ΔH°mic ΔS°mic et al. indicate that CnEO-5 molecules are exothermic and spontaneous during the micellization process. DLS, p-values, and TEM results indicate that anionic non-ionic Gemini surfactants with shorter hydrophobic chains (such as C8EO-5) tend to form larger vesicles in aqueous solutions, which are formed in a tail to tail and staggered manner; Negative non-ionic Gemini surfactants with longer hydrophobic chains (such as C12EO-5, C16EO-5) tend to form small micelles. The test results indicate that CnEO-5 anionic non-ionic Gemini surfactants have certain application prospects in improving crude oil recovery.

2.
Int J Mol Sci ; 25(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38673792

RESUMO

Arbuscular mycorrhizal fungi symbiosis plays important roles in enhancing plant tolerance to biotic and abiotic stresses. Aquaporins have also been linked to improved drought tolerance in plants and the regulation of water transport. However, the mechanisms that underlie this association remain to be further explored. In this study, we found that arbuscular mycorrhiza fungi symbiosis could induce the gene expression of the aquaporin ZmTIP2;3 in maize roots. Moreover, compared with the wild-type plants, the maize zmtip2;3 mutant also showed a lower total biomass, colonization rate, relative water content, and POD and SOD activities after arbuscular mycorrhiza fungi symbiosis under drought stress. qRT-PCR assays revealed reduced expression levels of stress genes including LEA3, P5CS4, and NECD1 in the maize zmtip2;3 mutant. Taken together, these data suggest that ZmTIP2;3 plays an important role in promoting maize tolerance to drought stress during arbuscular mycorrhiza fungi symbiosis.


Assuntos
Aquaporinas , Secas , Regulação da Expressão Gênica de Plantas , Micorrizas , Proteínas de Plantas , Simbiose , Zea mays , Zea mays/microbiologia , Zea mays/genética , Zea mays/metabolismo , Micorrizas/fisiologia , Simbiose/genética , Aquaporinas/metabolismo , Aquaporinas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Resistência à Seca
3.
Qual Life Res ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573387

RESUMO

PURPOSE: This study summarized characteristics and risk factors of caregiver burden in PD patients and used meta-analysis to verify the effectiveness of the intervention on caregiver burden. METHODS: Systematic review and meta-analysis were conducted. RESULTS: Forty-nine articles that involved 5387 caregivers of patients with PD were included in this study. Results of systematic review indicated that Zarit burden Inventory (ZBI) was the most used scale to measure the caregiver burden. All scales revealed caregivers of PD patients had mild to moderate caregiver burden. For the PD patients with longer disease duration, severer disease severity, more negative emotion and cognition impairment, their caregivers intended to have higher caregiver burden. The caregiver with negative emotion and who spent more time on caregiving indicated higher caregiver burden than the others. The caregiver burden was not improved after deep brain stimulation (DBS). Meta-analysis showed that cognitive behavior therapy and palliative care had no significant effect to reduce caregiver burden in PD patients' caregiver. CONCLUSION: Caregivers of PD patients experienced mild to moderate caregiver burden. Demographic factor, diseased-related factor and negative emotional factor were the risk factors of caregiver burden. Health education and care support for long-term management after DBS surgery should be provided for patients and caregivers to decrease caregiver burden.

4.
J Extracell Vesicles ; 13(2): e12410, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38320981

RESUMO

Extracellular vesicles (EVs) exert a significant influence not only on the pathogenesis of diseases but also on their therapeutic interventions, contingent upon the variances observed in their originating cells. Mitochondria can be transported between cells via EVs to promote pathological changes. In this study, we found that EVs derived from M1 macrophages (M1-EVs), which encapsulate inflammatory mitochondria, can penetrate pancreatic beta cells. Inflammatory mitochondria fuse with the mitochondria of pancreatic beta cells, resulting in lipid peroxidation and mitochondrial disruption. Furthermore, fragments of mitochondrial DNA (mtDNA) are released into the cytosol, activating the STING pathway and ultimately inducing apoptosis. The potential of adipose-derived stem cell (ADSC)-released EVs in suppressing M1 macrophage reactions shows promise. Subsequently, ADSC-EVs were utilized and modified with an F4/80 antibody to specifically target macrophages, aiming to treat ferroptosis of pancreatic beta cells in vivo. In summary, our data further demonstrate that EVs secreted from M1 phenotype macrophages play major roles in beta cell ferroptosis, and the modified ADSC-EVs exhibit considerable potential for development as a vehicle for targeted delivery to macrophages.


Assuntos
Vesículas Extracelulares , Ferroptose , Células Secretoras de Insulina , Pancreatite , Humanos , Doença Aguda , Células Secretoras de Insulina/metabolismo , Pancreatite/metabolismo , Vesículas Extracelulares/metabolismo , Macrófagos/metabolismo , Mitocôndrias
5.
Langmuir ; 39(21): 7268-7280, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37203173

RESUMO

Inkjet printing has the advantages of high material utilization, low cost, and large-area production and is a promising manufacturing technology for organic light-emitting diode (OLED) displays. However, the droplet evaporation in micron-size pixel pits is highly influenced by the pit wall. Such a process is extremely difficult to control, leading to the appearance of defects such as the coffee ring in the printing process of OLED displays. In this work, a multiphase thermal lattice Boltzmann (LB) model based on multiple distribution functions is established to study the evaporation process of micron-size droplets in pits. According to the characteristics of the largest number of the three-phase contact line (TCL) appearing in the evaporation process, the evaporation modes can be divided into three types, i.e., one, two, and three TCLs. In the 1-TCL mode, the droplet stays in constant contact radius (CCR) for the shortest time; in 2-TCL and 3-TCL modes, the liquid film fracture behavior of evaporating droplets in the pit is well captured. The effects of the pit height and the contact angle on the droplet evaporation mode are investigated in detail. The phase diagrams of evaporation modes with different parameters are also established. The revealed evaporation mechanism is supposed to be useful for regulating the droplet evaporation behavior and controlling the cured film shape in the OLED printing process.

6.
Sci Bull (Beijing) ; 68(11): 1187-1194, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37179230

RESUMO

During the 7-9th century, the Tibetan Empire constituted a superpower between the Tang Empire and Abbasid Caliphate: one that played significant roles in geopolitics in Asia during the Early Medieval Period. The factors which led to the rise and rapid decline of this powerful Empire, the only united historical regime on the Tibetan Plateau (TP), remain unclear. Sub-annual scale precipitation and decadal-scale temperature records of the central TP are presented, indicating that the height of this Empire coincided with a two-century long interval of uncharacteristically warm and humid climate. The ameliorated climate enabled the expansion of arable land and increased agricultural production. The close relationship between the precipitation records and historical events implied that the Empire implemented flexible strategies to tackle the effects of climate changes. This has implications for agricultural production in alpine regions including the TP, in the context of current global warming.


Assuntos
Mudança Climática , Aquecimento Global , Tibet , Temperatura , Agricultura
7.
ISA Trans ; 134: 58-73, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36150903

RESUMO

Ship motion planning is a core issue of autonomous navigation for maritime autonomous surface ships (MASS). This paper proposes a novel model predictive artificial potential field (MPAPF) motion planning method for complex encounter scenarios considering collision avoidance rules. A new ship domain is established, in which a closed interval potential field function is designed to represent the inviolable properties of the ship domain. A Nomoto model with a predefined speed during motion planning is adopted to generate followable paths conforming to the ship kinematics. To solve the local optima problem of traditional artificial potential field (APF) method and guarantee the collision avoidance safety in complex encounter scenarios, a motion planning method based on model predictive strategy and artificial potential field, i.e., MPAPF, is proposed. In this method, the ship motion planning problem is transformed to a non-linear optimization problem with multiple constraints including maneuverability, navigation rules, navigable waterway, etc. Simulation results from 4 case studies show that the proposed MPAPF algorithm can solve the problems above and generate feasible motion paths to avoid ship collision in complex encounter scenarios compared to variants of APF, A-star and rapidly-exploring random trees (RRT).

8.
J Inflamm Res ; 16: 6397-6413, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38161354

RESUMO

Aim: Acute pancreatitis is an inflammatory disorder of the pancreas, which causes abnormal activation of immune cells. The macrophages were accumulated in pancreas and infiltrated into islets during the AP process to induce abnormal glucose metabolism. However, the role of macrophages in abnormal glucose metabolism remains understood. Extracellular vesicles act in the regulation of intercellular function, but whether EVs secreted by macrophages contribute to ß cell failure and apoptosis in AP is unclear. Based on this, the aim of this study was to reveal the role of macrophages-EVs in AP and develop a treatment for symptoms of hyperglycemia in AP. Methods: The AP model was established and treated by various doses of melatonin to analyze the therapeutic effect. The accumulation and polarization of macrophages in the AP pancreas were observed, and the ß cells were incubated with pancreatic derived EVs to analyze the role in ß cell failure and apoptosis. Results: The results showed that macrophages were recruited and polarized to M1 phenotype macrophages in the pancreas of AP mice, which obtained inflammatory EVs that contained specific miRNAs to induce ß cell failure and apoptosis. Then, the EVs derived from M1 macrophages triggered ß cell failure and apoptosis. Melatonin prevented polarization of macrophages to the M1 phenotype in vivo, which reduced the secretion of inflammatory EVs, changed the abundance of miRNAs in EVs, and therefore decreased inflammatory EV-mediated ß cell failure and apoptosis. Conclusion: Our results demonstrate that similar to 20S proteasome inhibitor MG132, analyses indicated that melatonin prevented degradation of IκBα through the ubiquitylation pathway to restrict p50 subunits to the cytoplasm of macrophages, inhibited activation of the NF-κB pathway to downregulate the transcription of specific miRNAs, and reduced miRNA transport into EVs.

9.
Heliyon ; 8(12): e11995, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36561684

RESUMO

Background: Type 1 diabetes mellitus (T1DM) is an autoimmune disease caused by an autoimmune response against pancreatic islet ß cells. Increasing evidence indicates that specific microRNAs (miRNAs) from immune cells extracellular vesicles are involved in islet ß cells apoptosis. Methods: In this study, the microarray datasets GSE27997 and GSE137637 were downloaded from the Gene Expression Omnibus (GEO) database. miRNAs that promote islet ß cells apoptosis in T1DM were searched in PubMed. We used the FunRich tool to determine the miRNA expression in extracellular vesicles derived from immune cells associated with islet ß cell apoptosis, of which we selected candidate miRNAs based on fold change expression. Potential upstream transcription factors and downstream target genes of candidate miRNAs were predicted using TransmiR V2.0 and starBase database, respectively. Results: Candidate miRNAs expressed in extracellular vesicles derived from T cells, pro-inflammatory macrophages, B cells, and dendritic cells were analyzed to identify the miRNAs involved in ß cells apoptosis. Based on these candidate miRNAs, 25 downstream candidate genes, which positively regulate ß cell functions, were predicted and screened; 17 transcription factors that positively regulate the candidate miRNAs were also identified. Conclusions: Our study demonstrated that immune cell-derived extracellular vesicular miRNAs could promote islet ß cell dysfunction and apoptosis. Based on these findings, we have constructed a transcription factor-miRNA-gene regulatory network, which provides a theoretical basis for clinical management of T1DM. This study provides novel insights into the mechanism underlying immune cell-derived extracellular vesicle-mediated islet ß cell apoptosis.

10.
Front Vet Sci ; 8: 746224, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34901243

RESUMO

A high-quality protein substitute, Hermetia illucens (black soldier fly) larvae powder, is rich in protein and often used in animal feed. This study aimed to investigate the feasibility and optimal ratio of replacing fish meal with H. illucens larvae in weaned piglets and to demonstrate the effects on piglets' growth performance, intestinal microflora and immune performance. Forty-eight female weaned piglets were randomly classified into three groups. Each group consisted of eight pens (replicates), with two piglets per pen. Three groups containing different proportions of H. illucens larvae (0, 4, and 8%) were referred to as C, HI4, and HI8. We first designed a 28-day feeding experiment to detect growth performance; after that, the piglets were induced with oral gavage of enterotoxigenic Escherichia coli K88 (ETEC K88) and recording diarrhea on day 29 of the experiment. Samples were taken on the 32nd day to detect the effect of H. illucens larvae on the immune performance of the weaned piglets. H. illucens larvae replacement did not cause any obvious change in the growth performance nether in HI4 nor in HI8 of weaned piglets with 28 d feeding stage. H. illucens larvae could improve the intestinal health of weaned piglets by increasing the content of Lactobacillus and reducing the content of Streptococcus. Compared with C+K88 group, the diarrhea rate was attenuated for the H. illucens supplemented group. The integrity of ileum villi in HI4+K88 and HI8+K88 groups was better than that in C+K88 group, and the villi in C+K88 group were severely damaged. The expression of IL-10, Occludin and Claudin-3 in the intestinal mucosa of the HI4+K88 group and HI8+K88 group were significantly increased (P < 0.05), and the expression of TNF-α was significantly decreased (P < 0.05) compared with the C+K88 group. The results of immunoblotting also validated that the same ETEC K88 treatment of weaned piglets enhanced the expression of tight junction protein in the intestinal mucosa of the H. illucens addition group. ETEC-induced diarrhea will be reduced by the diet of weaned piglets containing H. illucens larvae, ameliorating the immune performance of piglets. Our results indicates that the optimal dosage of H. illucens replacement in weaned piglets is 4%.

11.
Environ Monit Assess ; 192(7): 464, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601791

RESUMO

Ground deformation (GD) has been widely reported as a global issue and is now an ongoing problem that will profoundly endanger the public safety. GD is a complex and dynamic problem with many contributing factors that occur over time. In the literature, there are only a few methods that can effectively monitor GD. Microwave remote sensing data such as interferometric synthetic aperture radar (InSAR) are mostly adopted to assess GD. These data can reveal the surface deforming areas with great precision, mapping GD results at a large scale. In this study, the effects of GD and the influencing factors, such as the building area, the water level, the cumulative precipitation, and the cumulative temperature, are modeled in the Erhai region with small baseline subset interferometric SAR (SBAS-InSAR) data that are applied using machine learning (ML) methods. The ML methods, namely, multiple linear regression (MLR), multilayer perceptron backpropagation (MLP-BP), least squares support vector machine (LSSVM), and particle swarm optimization (PSO)-LSSVM, are used to predict GD, and the results are compared. Particularly, the PSO-LSSVM method has obtained the least root mean square error (RMSE) and mean relative error (MRE) of 11.448 and 0.112, respectively. Therefore, the results have proven that the proposed PSO-LSSVM is very efficient in analyzing GD.


Assuntos
Monitoramento Ambiental , Aprendizado de Máquina , China , Redes Neurais de Computação , Máquina de Vetores de Suporte
12.
Environ Monit Assess ; 192(8): 523, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32676738

RESUMO

Unfortunately, the name of the corresponding author (Wenxiang Wu) was missing in the author group section of the published paper.

13.
Polymers (Basel) ; 12(4)2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-32290460

RESUMO

Polymer microsphere profile control is a promising approach for the profile control of heterogeneous reservoirs. Matching between polymer microspheres and the reservoir pore throat is crucial for profile control. In this study, the range of the optimal matching factor Ra between polymer microspheres and core porosity was divided through core permeability limit experiments, and the dynamic migration laws and shut-off patterns of microspheres were studied using 9-m-long cores and microscopic models. The oil displacement effect and mechanism of microspheres were analyzed using three cores in parallel. The "injectability limit" and "in-depth migration limit" curves were divided by Ra into three zones: blockage (Ra < 1.09 ± 0.10), near-well profile control (1.09 ± 0.10 < Ra < 5.70 ± 0.64), and in-depth fluid diversion (Ra > 5.70 ± 0.64). During migration in porous media, the microspheres gradually enlarged in size and thus successively shut off in four forms: multi-microsphere bridging shut-off, few-microsphere bridging shut-off, single-microsphere shut-off, and elastic shut-off. Microspheres with a rational combination of sizes versus those with a single particle size further enhanced reservoir oil recovery under certain reservoir conditions. Through "temporary shut-off-breakthrough-temporary shut-off," the polymer microspheres were able to change the fluid flow rate and streamlines, mobilize residual oils, and enhance the oil recovery rates.

14.
J Comput Biol ; 26(10): 1168-1176, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31246501

RESUMO

We attempted to analyze the aberrant pathways and genes underlying the successive stages of colorectal cancer (CRC). The CRC related microarray data (GSE77953) were retrieved from Gene Expression Omnibus database, which included 17 colonic adenoma, 17 carcinoma, 11 CRC metastases, and 13 normal colonic epithelium samples. The differential expression patterns in colonic adenoma, carcinoma, and metastases were analyzed. Gene functional interaction (FI) and coexpressed network were constructed. Pathway enrichment analysis was performed to investigate the perturbed pathways, and disease-related genes were explored based on the Comparative Toxicogenomics Database. Total 438 genes were identified to be differentially expressed in colonic adenoma, 885 in carcinoma and 736 in metastases. The upregulated genes in adenoma were significantly related with ribosome, oxidative phosphorylation, and protein export related pathways. The downregulated genes in carcinoma and metastases were enriched in the same pathways, such as nitrogen metabolism, mineral absorption, and steroid hormone biosynthesis. FI network was constructed with 219 and 3914 edges, which were further divided to 12 modules. The genes in module 0 were closely related with ribosome, protein export, and RNA transport. Coexpressed genes were enriched in ribosome, protein export, and mineral absorption pathways. Total eight common upregulated genes were found to be the CRC-related genes such as RNF43 (ring finger protein 43), EIF3H (eukaryotic translation initiation factor 3 subunit H), and STRAP (serine/threonine kinase receptor associated protein). The common downregulated genes included ABCG2 (ATP binding cassette subfamily G member 2), GCG (glucagon), and SULT1A1 (sulfotransferase family 1A member 1). Oxidative phosphorylation, nitrogen metabolism, mineral absorption, and protein synthesis may significantly be perturbed in the progression of CRC. The overexpression of EIF3H may be the predictor for CRC formation.


Assuntos
Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , Progressão da Doença , Perfilação da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Genômica , Humanos
15.
Sci Rep ; 8(1): 7855, 2018 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-29777204

RESUMO

While North China is one of the earliest independent centers for cereal domestication in the world, the earliest stages of the long process of agricultural origins remain unclear. While only millets were eventually domesticated in early sedentary societies there, recent archaeobotanical evidence reported here indicates that grasses from the Paniceae (including millets) and Triticeae tribes were exploited together by foraging groups from the Last Glacial Maximum to the mid-Holocene. Here we explore how and why millets were selected for domestication while Triticeae were abandoned. We document the different exploitation and cultivation trajectories of the two tribes employing ancient starch data derived from nine archaeological sites dating from 25,000 to 5500 cal BP (LGM through mid-Holocene) in North China. With this diachronic overview, we can place the trajectories into the context of paleoclimatic reconstructions for this period. Entering the Holocene, climatic changes increased the yield stability, abundance, and availability of the wild progenitors of millets, with growing conditions increasingly favoring millets while becoming more unfavorable for grasses of the Triticeae tribe. We thus hypothesize that climate change played a critical role in the selection of millet species for domestication in North China, with early domestication evidenced by 8700 cal BP.


Assuntos
Mudança Climática , Domesticação , Milhetes/crescimento & desenvolvimento , Arqueologia , China , Amido/análise
16.
Science ; 355(6332): 1382, 2017 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-28360291

RESUMO

Wu et al (Reports, 5 August 2016, p. 579) reported geological and archaeological evidence about an earthquake-induced landslide dam outburst flood around 1920 BCE and claimed a support to the historicity of China's legendary Great Flood and Xia dynasty. We argue that the physical evidence is unreliable and their arguments are unconvincing.

18.
Chin Med J (Engl) ; 129(10): 1161-5, 2016 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-27174323

RESUMO

BACKGROUND: Vulvovaginal candidiasis (VVC) was a common infection associated with lifelong harassment of woman's social and sexual life. The purpose of this study was to describe the species distribution and in vitroCandidaCandida spp.) isolated from patients with VVC over 8 years. METHODS: Species which isolated from patients with VVC in Peking University First Hospital were identified using chromogenic culture media. Susceptibility to common antifungal agents was determined using agar diffusion method based on CLSI M44-A2 document. SPSS software (version 14.0, Inc., Chicago, IL, USA) was used for statistical analysis, involving statistical description and Chi-square test. RESULTS: The most common strains were Candida (C.) albicans, 80.5% (n = 1775) followed by C. glabrata, 18.1% (n = 400). Nystatin exhibited excellent activity against all species (<4% resistant [R]). Resistance to azole drugs varied among different species. C. albicans: clotrimazole (3.1% R) < fluconazole (16.6% R) < itraconazole (51.5% R) < miconazole (54.0% R); C. glabrata: miconazole (25.6% R) < clotrimazole (50.5% R) < itraconazole (61.9% R) < fluconazole (73.3% R); Candida krusei: clotrimazole (0 R) < fluconazole (57.7% R) < miconazole (73.1% R) < itraconazole (83.3% R). The susceptibility of fluconazole was noticeably decreasing among all species in the study period. CONCLUSIONS: Nystatin was the optimal choice for the treatment of VVC at present. The species distribution and in vitroCandida spp. isolated from patients with VVC had changed over time.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candidíase Vulvovaginal/microbiologia , Candida/patogenicidade , China , Clotrimazol/farmacologia , Farmacorresistência Fúngica , Feminino , Fluconazol/farmacologia , Humanos , Itraconazol/farmacologia , Miconazol/farmacologia , Testes de Sensibilidade Microbiana
19.
J Sci Food Agric ; 95(14): 2838-49, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25428548

RESUMO

BACKGROUND: Climate change would cause negative impacts on future agricultural production and food security. Adaptive measures should be taken to mitigate the adverse effects. The objectives of this study were to simulate the potential effects of climate change on maize yields in Heilongjiang Province and to evaluate two selected typical household-level autonomous adaptive measures (cultivar changes and planting time adjustments) for mitigating the risks of climate change based on the CERES-Maize model. RESULTS: The results showed that flowering duration and maturity duration of maize would be shortened in the future climate and thus maize yield would reduce by 11-46% during 2011-2099 relative to 1981-2010. Increased CO2 concentration would not benefit maize production significantly. However, substituting local cultivars with later-maturing ones and delaying the planting date could increase yields as the climate changes. CONCLUSION: The results provide insight regarding the likely impacts of climate change on maize yields and the efficacy of selected adaptive measures by presenting evidence-based implications and mitigation strategies for the potential negative impacts of future climate change.


Assuntos
Agricultura , Biomassa , Mudança Climática , Clima , Modelos Biológicos , Zea mays/crescimento & desenvolvimento , Adaptação Fisiológica , Dióxido de Carbono , China , Produtos Agrícolas , Características da Família , Abastecimento de Alimentos , Humanos , Desenvolvimento Vegetal , Especificidade da Espécie , Temperatura
20.
Risk Anal ; 34(4): 614-39, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24673569

RESUMO

The identification of societal vulnerable counties and regions and the factors contributing to social vulnerability are crucial for effective disaster risk management. Significant advances have been made in the study of social vulnerability over the past two decades, but we still know little regarding China's societal vulnerability profiles, especially at the county level. This study investigates the county-level spatial and temporal patterns in social vulnerability in China from 1980 to 2010. Based on China's four most recent population censuses of 2,361 counties and their corresponding socioeconomic data, a social vulnerability index for each county was created using factor analysis. Exploratory spatial data analysis, including global and local autocorrelations, was applied to reveal the spatial patterns of county-level social vulnerability. The results demonstrate that the dynamic characteristics of China's county-level social vulnerability are notably distinct, and the dominant contributors to societal vulnerability for all of the years studied were rural character, development (urbanization), and economic status. The spatial clustering patterns of social vulnerability to natural disasters in China exhibited a gathering-scattering-gathering pattern over time. Further investigations indicate that many counties in the eastern coastal area of China are experiencing a detectable increase in social vulnerability, whereas the societal vulnerability of many counties in the western and northern areas of China has significantly decreased over the past three decades. These findings will provide policymakers with a sound scientific basis for disaster prevention and mitigation decisions.


Assuntos
Desastres , Populações Vulneráveis , Fatores Etários , China , Análise Fatorial , Feminino , Abastecimento de Alimentos , Humanos , Masculino , Dinâmica Populacional , Fatores Sexuais , Classe Social , Fatores de Tempo , Desemprego
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