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1.
Biomacromolecules ; 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34762396

RESUMO

Oxidation-sensitive drug delivery systems (DDSs) have attracted attention due to the potential to improve efficacy and safety of chemotherapeutics. These systems are designed to release the payload in response to oxidative stress conditions, which are associated with many types of cancer. Despite extensive research on the development of oxidation-sensitive DDS, the lack of selectivity toward cancer cells over healthy cells remains a challenge. Here, we report the design and characterization of polymeric micelles containing thioether groups with varying oxidation sensitivities within the micellar core, which become hydrophilic upon thioether oxidation, leading to destabilization of the micellar structure. We first used the thioether model compounds, 3-methylthiopropylamide (TPAM), thiomorpholine amide (TMAM), and 4-(methylthio)benzylamide (TPhAM) to investigate the effect of the chemical structures of the thioethers on the oxidation by hydrogen peroxide (H2O2). TPAM shows the fastest oxidation, followed by TMAM and TPhAM, showing that the oxidation reaction of thioethers can be modulated by changing the substituent groups bound to the sulfur atom. We next prepared micelles containing these different thioether groups within the core (TP, TM, and TPh micelles). The micelles containing the thioether groups with a higher oxidation sensitivity were destabilized by H2O2 at a lower concentration. Micelle destabilization was also tested in human liver cancer (HepG2) cells and human umbilical vein endothelial cells (HUVECs). The TP micelles having the highest oxidation sensitivity were destabilized in both HepG2 cells and HUVECs, while the TPh micelles, which showed the lowest reactivity toward H2O2, were stable in these cell lines. The TM micelles possessing a moderate oxidation sensitivity were destabilized in HepG2 cells but were stable in HUVECs. Furthermore, the micelles were loaded with doxorubicin (Dox) to evaluate their potential in drug delivery applications. Among the micelles, the TM micelles loaded with Dox showed the enhanced relative toxicity in HepG2 cells over HUVECs. Therefore, our approach to fine-tune the oxidation sensitivity of the micelles has potential for improving therapeutic efficacy and safety of drugs in cancer treatment.

2.
Clin Interv Aging ; 16: 1917-1929, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737556

RESUMO

Background: The incidence and mortality rate of community-acquired pneumonia (CAP) in elderly patients were higher than the younger population. Different scoring systems, including The quick Sequential Organ Function Assessment (qSOFA), Combination of Confusion, Urea, Respiratory Rate, Blood Pressure, and Age ≥65 (CURB-65), Modified Early Warning Score (MEWS) and National Early Warning Score (NEWS), were used widely for predicting mortality and ICU admission of patients with community-acquired pneumonia (CAP). This study aimed to identify the most suitable score system for better hospitalization. Methods: We retrospectively analyzed elderly patients with CAP in Minhang Hospital, Fudan University from 1 January 2018 to 1 January 2020. We recorded information of the patients including age, gender, underlying disease, consciousness state, vital signs, physiological and laboratory variables and further calculated the qSOFA, CURB-65, MEWS, and NEWS scores. Receiver operating characteristic (ROC) curves were used to predict the mortality risk and ICU admission. Kaplan-Meier survival curves were used in survival rate. Results: In total, 1044 patients were selected for analysis and divided into two groups, namely survivor groups (902 cases) and non-survivor groups (142 cases). Depending on ICU admission enrolled patients were classified into ICU admission (n = 102) and non-ICU admission (n = 942) groups. Mortality expressed as AUC values were 0.844 (p < 0.001), 0.868 (p < 0.001), 0.927 (p < 0.001) and 0.892 (p < 0.001) for qSOFA, CURB 65, MEWS and NEWS, respectively. There were clear differences in MEWS vs CURB-65 (p < 0.0001), MEWS vs NEWS (p < 0.001), MEWS vs qSOFA (p < 0.0001). For ICU-admission, the AUC values of qSOFA, CURB-65, MEWS and NEWS scores were 0.866 (p < 0.001), 0.854 (p < 0.001), 0.922 (p < 0.001), 0.976 (p < 0.001), respectively. There were significant differences in NEWS vs CURB-65 (p < 0.0001), NEWS vs MEWS (p < 0.001), NEWS vs qSOFA (p < 0.0001). Conclusion: We explored the outcome prediction values of CURB65, qSOFA, MEWS and NEWS for patients aged 65-years and older with community-acquired pneumonia. We found that MEWS showed superiority over the other severity scores in predicting hospital mortality, and NEWS showed superiority over the other scores in predicting ICU admission.


Assuntos
Pneumonia , Sepse , Idoso , Mortalidade Hospitalar , Hospitalização , Humanos , Unidades de Terapia Intensiva , Escores de Disfunção Orgânica , Prognóstico , Curva ROC , Estudos Retrospectivos
3.
Int J Nurs Sci ; 8(4): 394-400, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34631989

RESUMO

Objectives: This study aimed to explore the dignity and related factors among older adults in long-term care facilities. Methods: Cross-sectional data were obtained from a sample of 253 Chinese older adults dwelling in long-term care facilities. Dignity among older adults was measured using the Dignity Scale, and its potential correlates were explored using multiple linear regressions. Results: Results showed that the total score of the Dignity Scale is 151.95 ± 11.75. From high to low, the different factors of dignity among older adults in long-term care facilities were as follows: caring factors (4.83 ± 0.33), social factors (4.73 ± 0.41), psychological factors (4.66 ± 0.71), value factors (4.56 ± 0.53), autonomous factors (4.50 ± 0.57), and physical factors (4.38 ± 0.55). A higher score of the Dignity Scale was associated with higher economic status, fewer chronic diseases, less medication, better daily living ability and long-time lived in cities. Conclusion: Older adults with low economic status, more chronic diseases, and poor daily living ability, taking more medications, or the previous residence in rural areas seem to be most at low-level dignity in long-term care facilities and thus require more attention than their peers.

4.
Genes Genomics ; 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34609723

RESUMO

BACKGROUND: Gliomas, especially Glioblastoma multiforme, are the most frequent type of primary tumors in central nervous system. Increasing researches have revealed the relationship between autophagy and tumor, while the molecular mechanism of autophagy in glioma is still rarely reported. OBJECTIVE: Our research aims to conform the autophagy-related genes (ARGs) implicated in the development and progression of glioma and improve our understanding of autophagy in glioma. METHODS: 20 candidate ARGs were screened through the protein-protein interaction network. We also downloaded the publicly accessible glioma data for 665 individuals from TCGA and 970 individuals from CGGA with RNA sequences and clinicopathological information. Subsequently, univariate and multivariate Cox regression analysis identified 5 key ARGs among the 20 candidate genes as key prognostic genes for survival, GSEA and immune response analysis. RESULTS: ATG5, BCL2L1, CASP3, CASP8, GAPDH were identified as key ARGs in our research. Further studies showed that the high-risk population was linked to a dismal prognosis and suggested an immune-inhibitory microenvironment. GSEA results demonstrated that high risk population was closely related to DNA repair, hypoxia pathways, implicated in immunosuppression and carcinogenesis. Through CMap, we finally identified 14 candidate drugs for the ARG high risk population. CONCLUSIONS: This study established and verified an ARG risk model, which can serve as an independent predictor for prognosis, reflect on the strength of the immune response and predict the potential drugs in glioma. Our findings offer new understandings of ARG molecular mechanism and promising therapeutic targets for glioma treatment.

5.
Cell Biol Toxicol ; 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34713381

RESUMO

Sirt6, a class III NAD+-dependent deacetylase of the sirtuin family, is a highly specific H3 deacetylase and plays important roles in regulating cellular growth and death. The induction of oxidative stress and death is the critical mechanism involved in cardiomyocyte injury and cardiac dysfunction in doxorubicin-induced cardiotoxicity, but the regulatory role of Sirt6 in the fate of DOX-impaired cardiomyocytes is poorly understood. In the present study, we exposed Sirt6 heterozygous (Sirt6+/-) mice and their littermates as well as cultured neonatal rat cardiomyocytes to DOX, then investigated the role of Sirt6 in mitigating oxidative stress and cardiac injury in the DOX-treated myocardium. Sirt6 partial knockout or silencing worsened cardiac damage, remodeling, and oxidative stress injury in mice or cultured cardiomyocytes with DOX challenge. Cardiomyocytes infected with adenoviral constructs encoding Sirt6 showed reversal of this DOX-induced damage. Intriguingly, Sirt6 reduced oxidative stress injury by upregulating endogenous antioxidant levels, interacted with oxidative stress-stirred p53, and acted as a co-repressor of p53 in nuclei. Sirt6 was recruited by p53 to the promoter regions of the target genes Fas and FasL and further suppressed p53 transcription activity by reducing histone acetylation. Sirt6 inhibited Fas/FasL signaling and attenuated both Fas-FADD-caspase-8 apoptotic and Fas-RIP3 necrotic pathways. These results indicate that Sirt6 protects the heart against DOX-induced cardiotoxicity by upregulating endogenous antioxidants, as well as suppressing oxidative stress and cell death signaling pathways dependent on ROS-stirred p53 transcriptional activation, thus reducing Fas-FasL-mediated apoptosis and necrosis. •Sirt6 is significantly decreased in DOX-insulted mouse hearts and cardiomyocytes. •Sirt6 attenuates DOX-induced cardiac atrophy, dysfunction and oxidative stress. • Sirt6 reduces oxidative stress injury by upregulating endogenous antioxidants. • Sirt6 interacts with p53 as a co-repressor to suppress p53 transcriptional regulation and inhibits Fas-FasL-mediated apoptosis and necrosis downstream of p53.

6.
Mar Pollut Bull ; 173(Pt B): 113051, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34710671

RESUMO

Microplastic pollution has received substantial international attention in terrestrial and marine environments and in the atmosphere. In this study, we assessed microplastic pollution and analyzed the accumulation of microplastics in the gills of fish caught in the Zhoushan fishing ground from September 2017 to March 2018. The average abundance of microplastics was 0.49 ± 0.54 particles/gill and frequently found chemical polymers was polyethylene terephthalate. We also conducted experiments on microplastic pollution in the water and the working solutions used during the analytical process and found that the source of microplastic contamination was the solutions used. Moreover, we evaluated and scored experimental quality control and quality assurance adapted from the 'Total Accumulated Score' method. Valuable steps are recommended in order to produce reliable results and improve the quality of results in microplastic analyses.

7.
J Hypertens ; 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34475349

RESUMO

BACKGROUND: Hypertension, as one of the most common chronic diseases, is a major public health issue. Previous studies have shown that there are miRNAs differentially expressed in hypertensive patients. In addition, hypertension is closely related to endothelial dysfunction, and miRNAs have been identified as important molecular mediators for endothelial function. Therefore, it is necessary to identify specific miRNAs related to hypertension and explore their molecular mechanism in the progression of hypertension. METHODS: We investigated the association of circulating levels of miR-3656 with hypertension. Furthermore, in-vitro studies were performed to investigate its possible mechanisms for hypertension in that the direct target genes of miR-3656 were confirmed using dual-luciferase reporter assay; moreover, the effects of miR-3656 on proliferation, migration, apoptosis, and microvascular rarefaction of HUVECs were investigated using MTS kit, wound-healing assay, FITC Annexin V apoptosis detection kit, and tube formation assay, correspondingly. RESULTS: Circulating miR-3656 was upregulated in patients with hypertension. MiR-3656 suppressed the proliferation, migration, and angiogenesis of HUVECs, but promoted the apoptosis of HUVECs. In addition, eNOS and ADAMTS13 were direct target genes of miR-3656, and overexpression of eNOS and ADAMTS13 abolished the effect of miR-3656 on HUVECs. CONCLUSION: MiR-3656 is a potential biomarker for hypertension. MiR-3656 is involved in endothelial cellular injury implicated in hypertension by targeting eNOS and ADAMTS13.

8.
Sci Rep ; 11(1): 19365, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34588469

RESUMO

Genome-wide association studies have identified numerous common genetic variants associated with spirometric measures of pulmonary function, including forced expiratory volume in one second (FEV1), forced vital capacity, and their ratio. However, variants with lower minor allele frequencies are less explored. We conducted a large-scale gene-smoking interaction meta-analysis on exonic rare and low-frequency variants involving 44,429 individuals of European ancestry in the discovery stage and sought replication in the UK BiLEVE study with 45,133 European ancestry samples and UK Biobank study with 59,478 samples. We leveraged data on cigarette smoking, the major environmental risk factor for reduced lung function, by testing gene-by-smoking interaction effects only and simultaneously testing the genetic main effects and interaction effects. The most statistically significant signal that replicated was a previously reported low-frequency signal in GPR126, distinct from common variant associations in this gene. Although only nominal replication was obtained for a top rare variant signal rs142935352 in one of the two studies, interaction and joint tests for current smoking and PDE3B were significantly associated with FEV1. This study investigates the utility of assessing gene-by-smoking interactions and underscores their effects on potential pulmonary function.

9.
Chem Commun (Camb) ; 57(76): 9740-9743, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34474462

RESUMO

Here, we investigated the photochemistry of nano-plastic particles with different surface ligands and sizes (i.e. PS-NH2 40, 80, 100, 200 nm and PS-COOH 40, 80, 100, 200 nm) under a solar simulator. Our findings provide new insights into DNA cleavage and chemical transformation of nano-plastics, especially mediated by different ligands and sizes.


Assuntos
Nanopartículas/química , Poliestirenos/química , Clivagem do DNA , Ligantes , Tamanho da Partícula , Propriedades de Superfície
10.
BMC Cardiovasc Disord ; 21(1): 385, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34372765

RESUMO

BACKGROUND: Essential hypertension is a complex disease determined by the interaction of genetic and environmental factors, eNOS is considered to be one of the susceptible genes for hypertension. Our study aimed to evaluate the association between eNOS rs1799983 polymorphism and hypertension, and to provide evidence for the etiology of hypertension. METHODS: Case-control studies of eNOS rs1799983 polymorphism and hypertension were included by searching PubMed, Embase, Web of Science, Medline, Scopus, WanFang datebase, Vip datebase, and CNKI database according to PRISMA guideline. Eligible data were extracted and pooled, and were analyzed using R software based on five different genetic models. RESULTS: A total of 60 eligible articles involving 14,185 cases and 13,407 controls were finally selected. We found significant association between eNOS rs1799983 polymorphism and hypertension under any genetic model (T vs G: OR = 1.44, 95% CI 1.26-1.63; GT vs GG: OR 1.34, 95% CI 1.18-1.52; TT vs GG: OR 1.80, 95% CI 1.41-2.31; GT + TT vs GG: OR 1.42, 95% CI 1.25-1.63; TT vs GG + GT: OR 1.68, 95% CI 1.35-2.08; GT vs GG + TT: OR 1.24, 95% CI 1.11-1.40). CONCLUSIONS: We found that eNOS rs1799983 polymorphism is associated with the increased risk of hypertension under any genetic model. Moreover, investigations of gene-gene and gene-environment interactions are needed to give more insight into the association between eNOS rs1799983 polymorphism and hypertension.

11.
Nanotoxicology ; 15(8): 1073-1086, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34416130

RESUMO

This study attempts to explore the potential impact of titanium dioxide nanoparticles (n-TiO2) on bioconcentration and reproductive impairments of male zebrafish in the presence of 2,2',4,4'-tetrabromodiphenyl ether (BDE47), the congener of PBDEs predominant in environment and most abundant in biosamples. n-TiO2 nanoparticles strongly adsorbed BDE47 to form BDE47/TiO2 complex, which was taken up into the testes of zebrafish, and increased the tissue burdens of both BDE47 and n-TiO2. Correspondingly, no observed toxic dose of n-TiO2 (100 µg/L) was found to aggravate the abnormal histological morphology of the testes and the decrease in egg production, gonadosomatic index, sexual hormone levels and related gene expression in zebrafish in the presence of BDE47 at 5 or 50 µg/L. In addition, n-TiO2 exacerbated the destruction resulting from the ultrastructural disassembly of intercellular connectivity of germ cells in zebrafish and the decrease in transepithelial electrical resistance in TM4 cells induced by BDE47. Furthermore, n-TiO2 enhanced BDE47 to initially activate p-JNK MAPK signaling pathway and subsequently triggered the downregulation of junction proteins (i.e., ZO-1, Connexin-43 and N-cadherin), leading to impaired cell-cell junctions in vivo and in vitro. Our results demonstrated that n-TiO2 should act as a carrier to facilitate the accumulation of BDE47 in zebrafish testes and result in a synergistic effect on BDE47-induced adverse reproductive outcomes via disruption of intercellular connectivity of zebrafish testes. This study is beneficial in providing a scientific basis for improving the health risk assessment of environmental pollutants, particularly those that coexist with nanoparticle contamination in realistic environments.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Bioacumulação , Junções Intercelulares , Masculino , Nanopartículas/toxicidade , Testículo , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
12.
Light Sci Appl ; 10(1): 153, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315859

RESUMO

The fabrication of small-scale electronics usually involves the integration of different functional materials. The electronic states at the nanoscale interface plays an important role in the device performance and the exotic interface physics. Photoemission spectroscopy is a powerful technique to probe electronic structures of valence band. However, this is a surface-sensitive technique that is usually considered not suitable for the probing of buried interface states, due to the limitation of electron-mean-free path. This article reviews several approaches that have been used to extend the surface-sensitive techniques to investigate the buried interface states, which include hard X-ray photoemission spectroscopy, resonant soft X-ray angle-resolved photoemission spectroscopy and thickness-dependent photoemission spectroscopy. Especially, a quantitative modeling method is introduced to extract the buried interface states based on the film thickness-dependent photoemission spectra obtained from an integrated experimental system equipped with in-situ growth and photoemission techniques. This quantitative modeling method shall be helpful to further understand the interfacial electronic states between functional materials and determine the interface layers.

13.
Nat Prod Res ; : 1-7, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34180744

RESUMO

A new amide, baeriamide (1), along with nine known diketopiperazines (2-10), was isolated from the marine sponge Haliclona baeri. Their structures were identified by the means of UV, IR, MS and NMR. The absolute configuration of 1 was established by Marfey's method and comparing the specific optical rotation with the known compound HCO-Val-Gly methyl ester. Compound 1 was derived from dehydration of formylated L-valine with γ-amino-butanoic acid methyl ester. Compounds 2-10 were isolated from the genus of Haliclona for the first time. The absolute confirmation of 7 was confirmed first by the means of single-crystal X-ray diffraction. The cytotoxic, antibacterial, antiviral and antifouling activities of these compounds were also tested. However, none of them exhibited significant bioactivities.

14.
Sci Total Environ ; 792: 148437, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34153754

RESUMO

Microcystin-LR (MCLR) induced impairment to male reproductive system and revealed the effects of transgenerational toxicity on offspring. But very little is known about the inheritance of these effects to offspring and the mechanisms involved. Here, we used methylated DNA immunoprecipitation sequencing (MeDIP-Seq) and microarray to characterize whole-genome DNA methylation and mRNA expression patterns in zebrafish testis after 6-week exposure to 5 and 20 µg/L MCLR. Accompanied with these analyses it revealed that MAPK pathway and ER pathway significantly enriched in zebrafish testes. Apoptosis and testicular damage were also observed in testis. Next, we test the transmission of effects to compare control-father and MCLR exposure-father progenies. DNA methylation analyses (via reduced representation bisulfite sequencing) reveal that the enrichment of differentially methylated regions on neurodevelopment after paternal MCLR exposure. Meanwhile, several genes associated with neurodevelopment were markedly downregulated in zebrafish larvae, and swimming speed was also reduced in the larvae. Interestingly, paternal MCLR exposure also triggered activation the phosphorylation of mitogen-activated protein kinase (MAPK) pathway which is also associated with neurodevelopmental disorders. These results demonstrated the significant effect that paternal MCLR exposure may have on gene-specific DNA methylation patterns in testis. Inherited epigenetic alterations through the germline may be the mechanism leading to developmental neurotoxicity in the offspring.


Assuntos
Exposição Paterna , Peixe-Zebra , Animais , Epigênese Genética , Humanos , Masculino , Toxinas Marinhas , Microcistinas/toxicidade , Proteínas Quinases Ativadas por Mitógeno , Peixe-Zebra/genética
15.
J Hazard Mater ; 419: 126456, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34186430

RESUMO

Microplastic (MP) pollution in marine environments and organisms has received substantial international attention. However, long-term field studies of MPs are scarce. Here, we assessed the seasonal variation in MP abundance in the Zhoushan fishing ground (ZFG), one of the most abundant and productive fishing grounds worldwide, and analyzed the long-term MP accumulation in fish gastrointestinal tracts from September 2017 to June 2018. The most common MP particles in the ZFG were polyethylene terephthalate and polypropylene. After four seasons of continuous monitoring, we did not find accumulation of MPs in the fish after 10% KOH digestion. In total, 254 MP particles were removed from the gastrointestinal tracts of all fish. The average number of particles per fish was lower than that reported in previous global marine studies. There were significant differences among species. Moreover, this study provides the calculation of the weight of MPs ingested by fish and an estimate of the load of accumulated MPs in fish. According to the estimation, the load of MPs ingested by fish annually was approximately 3 kg in ZFG. These findings provide the long-term evidence of MP contamination in biota from the ZFG. The amounts of MPs ingested by fish require more detailed and improved investigation and estimation in further studies.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , China , Monitoramento Ambiental , Plásticos , Estações do Ano , Poluentes Químicos da Água/análise
16.
LGBT Health ; 8(5): 322-329, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34115955

RESUMO

Purpose: Sexual and gender minority (SGM) and racial/ethnic minority populations may differ in coronavirus disease 2019 (COVID-19) prevention, testing, and vaccine interest, although little research has explored these disparities. It is critical to understand the differential experiences within minoritized communities to ensure effective intervention and vaccine rollout. Methods: In a national online survey of U.S. adult SGM individuals, conducted between April and August 2020, 932 participants responded about COVID-19 testing, symptoms, interest in vaccination, and interest in at-home testing. Bivariate associations between these outcomes and demographic factors, including sexual orientation, gender identity, endorsing intersex traits, gender modality, race/ethnicity, and HIV status were calculated. Results: Despite 24% of the sample reporting COVID-19 symptoms, testing was relatively low at 13.3%. Transgender and bisexual/pansexual individuals were more likely to be interested in a COVID-19 vaccine and an at-home test compared with cisgender and gay/lesbian respondents, respectively. Compared with cisgender individuals, transgender individuals were nearly twice as likely to report COVID-19 symptoms. Latinx individuals were less likely to be interested in a future COVID-19 vaccination and Black individuals were less likely to be interested in an at-home COVID-19 test compared with White participants. Both respondents who endorsed intersex traits and people with HIV were less likely to be interested in an at-home test compared with those who did not endorse having intersex traits and people without HIV, respectively. Conclusions: These results show critical disparities in COVID-19 symptomology and prevention interest within SGM populations that must be taken into account when designing or tailoring effective COVID-19 interventions.


Assuntos
Atitude Frente a Saúde , Teste para COVID-19 , COVID-19/prevenção & controle , COVID-19/fisiopatologia , Minorias Sexuais e de Gênero , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Inquéritos e Questionários , Adulto Jovem
17.
Ying Yong Sheng Tai Xue Bao ; 32(5): 1643-1652, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34042358

RESUMO

In this study, with water salinity as the core index, sea-land hydrological connectivity index was constructed by integrating the hydrological structure connectivity index (water surface ratio, intake and outtake density, sea-land distance, and ditch distance). Based on multi-scale spatial analysis, we carried out the spatial quantitative analysis and classification of sea-land hydrological connectivity in the study area under an evaluation unit of 150 m×150 m grid. The results showed that sea-land hydrological connectivity gradually decreased from sea to land, with different decreasing rates. The spatial differentiation of water salinity in the study area was substantial, with certain impacts on the change rate of hydrological connectivity. The sea-land hydrological connectivity was divided into four grades, which was excellent, good, medium, and poor. The areas under excellent and good grades were mainly distributed in offshore areas, with saltwater aquaculture ponds and farmland as the main land use types. The regions with moderate and poor land use were mainly distributed in inland areas, with freshwater aquaculture ponds and farmland as the land use types. The hydrological process of coastal wetlands was complex. Quantitative coastal wetland hydrological connectivity could provide reference for coastal wetland status assessment and wetland restoration.


Assuntos
Salinidade , Áreas Alagadas , Água Doce , Hidrologia , Água
18.
Ying Yong Sheng Tai Xue Bao ; 32(5): 1653-1662, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34042359

RESUMO

Hydrological conditions in the plains irrigation area are complex, which are strongly affected by small irrigation facilities and human management. In this study, the connectivity index of ditch network and the influence index of rural small irrigation facilities were constructed to quantitatively analyze the hydrological connectivity of a typical plain irrigation area, Fudong irrigation area, in north Jiangsu Province. The self-organizing feature map (SOM) analysis method was used to identify the effects of small irrigation facilities on the spatial heterogeneity of ditch network structure connectivity. The results showed that the hydrological structure connectivity differed in different regions of Fudong. The connectivity in the north of the irrigation area was the best, but the worst in the central and southern part of the irrigation area. There were 876 pumps, 633 gates and 2420 culverts in the study area. Without the effects of small irrigation facilities, there were 13 villages with poor hydrological structure connectivity and 48 villages with good and best hydrological structure connectivity. Under the effects of small irrigation facilities, the number of villages with poor connectivity was reduced to 8, while the number of villages with good and best connectivity was increased to 53. Due to the influence of gates and culvert, the hydrological connectivity of 26 villages in Fudong became poor. The hydrological connectivity of 39 villages had been enhanced due to the existence of pump.


Assuntos
Hidrologia , China , Humanos
19.
IEEE Trans Vis Comput Graph ; 27(8): 3463-3480, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33856997

RESUMO

We present the Feature Tracking Kit (FTK), a framework that simplifies, scales, and delivers various feature-tracking algorithms for scientific data. The key of FTK is our simplicial spacetime meshing scheme that generalizes both regular and unstructured spatial meshes to spacetime while tessellating spacetime mesh elements into simplices. The benefits of using simplicial spacetime meshes include (1) reducing ambiguity cases for feature extraction and tracking, (2) simplifying the handling of degeneracies using symbolic perturbations, and (3) enabling scalable and parallel processing. The use of simplicial spacetime meshing simplifies and improves the implementation of several feature-tracking algorithms for critical points, quantum vortices, and isosurfaces. As a software framework, FTK provides end users with VTK/ParaView filters, Python bindings, a command line interface, and programming interfaces for feature-tracking applications. We demonstrate use cases as well as scalability studies through both synthetic data and scientific applications including tokamak, fluid dynamics, and superconductivity simulations. We also conduct end-to-end performance studies on the Summit supercomputer. FTK is open sourced under the MIT license: https://github.com/hguo/ftk.

20.
IEEE Trans Vis Comput Graph ; 27(6): 2808-2820, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33877980

RESUMO

We present a novel distributed union-find algorithm that features asynchronous parallelism and k-d tree based load balancing for scalable visualization and analysis of scientific data. Applications of union-find include level set extraction and critical point tracking, but distributed union-find can suffer from high synchronization costs and imbalanced workloads across parallel processes. In this study, we prove that global synchronizations in existing distributed union-find can be eliminated without changing final results, allowing overlapped communications and computations for scalable processing. We also use a k-d tree decomposition to redistribute inputs, in order to improve workload balancing. We benchmark the scalability of our algorithm with up to 1,024 processes using both synthetic and application data. We demonstrate the use of our algorithm in critical point tracking and super-level set extraction with high-speed imaging experiments and fusion plasma simulations, respectively.

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