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1.
Orphanet J Rare Dis ; 19(1): 342, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39272213

RESUMO

BACKGROUND: Hearing loss (HL) is the most common sensory birth deficit worldwide, with causative variants in more than 150 genes. However, the etiological contribution and clinical manifestations of X-linked inheritance in HL remain unclear within the Chinese HL population. In this study, we focused on X-linked hereditary HL and aimed to assess its contribution to hereditary HL and identify the genotype-phenotype relationship. METHODS: We performed a molecular epidemiological investigation of X-linked hereditary HL based on next-generation sequencing and third-generation sequencing in 3646 unrelated patients with HL. We also discussed the clinical features associated with X-linked non-syndromic HL-related genes based on a review of the literature. RESULTS: We obtained a diagnostic rate of 52.72% (1922/3646) among our patients; the aggregate contribution of HL caused by genes on the X chromosome in this cohort was ~ 1.14% (22/1922), and POU3F4 variants caused ~ 59% (13/22) of these cases. We found that X-linked HL was congenital or began during childhood in all cases, with representative audiological profiles or typical cochlear malformations in certain genes. Genotypic and phenotypic analyses showed that causative variants in PRPS1 and AIFM1 were mainly of the missense type, suggesting that phenotypic variability was correlated with the different effects that the replaced residues exert on structure and function. Variations in SMPX causing truncation of the protein product were associated with DFNX4, which resulted in typical audiological profiles before and after the age of 10 years, whereas nontruncated proteins typically led to distal myopathy. No phenotypic differences were identified in patients carrying POU3F4 or COL4A6 variants. CONCLUSIONS: Our work constitutes a preliminary evaluation of the molecular contribution of X-linked genes in heritable HL (~ 1.14%). The 15 novel variants reported here expand the mutational spectrum of these genes. Analysis of the genotype-phenotype relationship is valuable for X-linked HL precise diagnostics and genetic counseling. Elucidation of the pathogenic mechanisms and audiological profiles of HL can also guide choices regarding treatment modalities.


Assuntos
Doenças Genéticas Ligadas ao Cromossomo X , Perda Auditiva , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem , China , População do Leste Asiático/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Genômica , Genótipo , Perda Auditiva/genética , Mutação/genética , Fenótipo , Fatores do Domínio POU/genética
2.
Phytochemistry ; 227: 114227, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39067628

RESUMO

Phytochemical studies on the leaves and twigs of Garcinia oligantha Merr. led to the isolation of twelve previously undescribed depsidone derivatives (oliganthdepsidones A-L, 1-12). Their structures were elucidated by extensive spectroscopic analysis including 1H and 13C NMR, HSQC, HMBC and NOESY along with HRESIMS. The structures of oliganthdepsidones G and J were finally determined using DFT-NMR chemical shift calculations and DP4+ methods. Cytotoxicity test in four human cancer cell lines indicated that oliganthdepsidone F had relatively strong cytotoxic effect against A375 (melanoma), A549 (lung cancer), HepG2 (liver cancer), and MCF-7 (breast cancer) cell lines with IC50 of 18.71, 15.44, 10.92, and 15.90 µM, respectively. The dose- and time-dependent antiproliferative effects of oliganthdepsidone F on these cell lines were also observed by CCK-8 test. As determined by fluorescent microscopy and flow cytometry in these cell lines, oliganthdepsidone F could promote cell apoptosis, leading to the inhibition of cell proliferation. The results of wound healing assay and transwell assay showed that oliganthdepsidone F could inhibit the migration and invasion of A549 and MCF-7 cell lines in a concentration-dependent manner.


Assuntos
Antineoplásicos Fitogênicos , Apoptose , Proliferação de Células , Depsídeos , Ensaios de Seleção de Medicamentos Antitumorais , Garcinia , Lactonas , Humanos , Garcinia/química , Proliferação de Células/efeitos dos fármacos , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Depsídeos/química , Depsídeos/farmacologia , Depsídeos/isolamento & purificação , Estrutura Molecular , Lactonas/química , Lactonas/farmacologia , Lactonas/isolamento & purificação , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Linhagem Celular Tumoral , Folhas de Planta/química
3.
J Mol Diagn ; 26(7): 638-651, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38663495

RESUMO

Noninvasive prenatal diagnosis (NIPD) for autosomal recessive nonsyndromic hearing loss (ARNSHL) has been rarely reported until recent years. Additionally, the existing method can not be used for challenging genome loci (eg, copy number variations, deletions, inversions, or gene recombinants) or on families without proband genotype. This study assessed the performance of relative haplotype dosage analysis (RHDO)-based NIPD for identifying fetal genotyping in pregnancies at risk of ARNSHL. Fifty couples carrying pathogenic variants associated with ARNSHL in either GJB2 or SLC26A4 were recruited. The RHDO-based targeted linked-read sequencing combined with whole gene coverage probes was used to genotype the fetal cell-free DNA of 49 families who met the quality control standard. Fetal amniocyte samples were genotyped using invasive prenatal diagnosis (IPD) to assess the performance of NIPD. The NIPD results showed 100% (49/49) concordance with those obtained through IPD. Two families with copy number variation and recombination were also successfully identified. Sufficient specific informative single-nucleotide polymorphisms for haplotyping, as well as the fetal cell-free DNA concentration and sequencing depth, are prerequisites for RHDO-based NIPD. This method has the merits of covering the entire genes of GJB2 and SLC26A4, qualifying for copy number variation and recombination analysis with remarkable sensitivity and specificity. Therefore, it has clinical potential as an alternative to traditional IPD for ARNSHL.


Assuntos
Alelos , Conexina 26 , Haplótipos , Transportadores de Sulfato , Humanos , Transportadores de Sulfato/genética , Feminino , Gravidez , Polimorfismo de Nucleotídeo Único , Teste Pré-Natal não Invasivo/métodos , Conexinas/genética , Diagnóstico Pré-Natal/métodos , Variações do Número de Cópias de DNA , Surdez/genética , Surdez/diagnóstico , Genótipo , Masculino , Genes Recessivos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Proteínas de Membrana Transportadoras/genética
5.
BMC Med Genomics ; 17(1): 32, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38254107

RESUMO

BACKGROUND: Mutations in MPZL2, the characteristic genetic etiology of autosomal recessive deafness loci 111 (DFNB111), cause non-syndromic and moderate sensorineural hearing loss. METHODS: In this study, we analyzed the phenotype and genotype of eight pedigrees consisting of 10 hearing loss patients with bi-allelic pathogenic or likely pathogenic variants in MPZL2. These patients were identified from a 3272 Chinese patient cohort who underwent genetic testing. RESULTS: Apart from symmetrical and moderate sensorineural hearing loss, the MPZL2-related phenotype was characterized by progressive hearing loss with variation in the onset age (congenital defect to onset at the young adult stage). We determined that in the Chinese population, the genetic load of MPZL2 defects was 0.24% (8/3272) in patients diagnosed with hearing loss and 7.02% (8/114) in patients diagnosed with hereditary moderate sensorineural hearing loss caused by STRC, OTOA, OTOG, OTOGL, TECTA, MPZL2 and others. Three known MPZL2 variants (c.220C > T (p.Gln74*), c.68delC (p.Pro23Leufs*2), c.463delG (p.Ala155Leufs*10)) and a novel start loss variant (c.3G > T (p.Met1?)) were identified. MPZL2 c.220C > T was identified as the hotspot variant in the Chinese population and even in East Asia compared with c.72delA (p.Ile24Metfs*22) in European and West Asia through allele frequency. CONCLUSIONS: We concluded that apart from moderate HL, progressive HL is another character of MPZL2-related HL. No specified variant was verified for the progression of HL, the penetrance and expressivity cannot be determined yet. A novel MPZL2 variant at the start codon was identified, enriching the variant spectrum of MPZL2. The hotspot variants of MPZL2 vary in different ethnicities. This study provides valuable data for the diagnosis, prognosis evaluation and genetic counseling of patients with moderate sensorineural hearing loss related to MPZL2.


Assuntos
Surdez , Perda Auditiva Neurossensorial , Humanos , Adulto Jovem , Povo Asiático/genética , Moléculas de Adesão Celular , China , Surdez/etnologia , Surdez/genética , Perda Auditiva Neurossensorial/etnologia , Perda Auditiva Neurossensorial/genética , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de Membrana
6.
Materials (Basel) ; 16(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37048943

RESUMO

A porous CeO2 was synthesized following the addition of guanidine carbonate to a Ce3+ aqueous solution, the subsequent addition of hydrogen peroxide and a final hydrothermal treatment. The optimal experimental parameters for the synthesis of porous CeO2, including the amounts of guanidine carbonate and hydrogen peroxide and the hydrothermal conditions, were determined by taking the adsorption efficiency of acid orange 7 (AO7) dye as the evaluation. A template-free hydrothermal strategy could avoid the use of soft or hard templates and the subsequent tedious procedures of eliminating templates, which aligned with the goals of energy conservation and emission reduction. Moreover, both the guanidine carbonate and hydrogen peroxide used in this work were accessible and eco-friendly raw materials. The porous CeO2 possessed rapid adsorption capacities for AO7 dye. When the initial concentration of AO7 was less than 130 mg/L, removal efficiencies greater than 90.0% were obtained, achieving a maximum value of 97.5% at [AO7] = 100 mg/L and [CeO2] = 2.0 g/L in the first 10 min of contact. Moreover, the adsorption-desorption equilibrium between the porous CeO2 adsorbent and the AO7 molecule was basically established within the first 30 min. The saturated adsorption amount of AO7 dye was 90.3 mg/g based on a Langmuir linear fitting of the experimental data. Moreover, the porous CeO2 could be recycled using a NaOH aqueous solution, and the adsorption efficiency of AO7 dye still remained above 92.5% after five cycles. This study provided an alternative porous adsorbent for the purification of dye wastewater, and a template-free hydrothermal strategy was developed to enable the design of CeO2-based catalysts or catalyst carriers.

7.
Hum Genet ; 142(3): 419-430, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36576601

RESUMO

Waardenburg syndrome (WS) is a rare inherited autosomal dominant disorder caused by SOX10, PAX3, MITF, EDNRB, EDN3, and SNAI2. A large burden of pathogenic de novo variants is present in patients with WS, which may be derived from parental mosaicism. Previously, we retrospectively analyzed 90 WS probands with family information. And the frequency of de novo events and parental mosaicism was preliminary investigated in our previous study. In this study, we further explored the occurrence of low-level parental mosaicism in 33 WS families with de novo variants and introduced our procedure of quantifying low-level mosaicism. Mosaic single nucleotide polymorphisms (SNPs) were validated by amplicon-based next-generation sequencing (NGS); copy-number variants (CNVs) were validated by droplet-digital polymerase chain reaction (ddPCR). Molecular validation of low-level mosaicism of WS-causing variants was performed in four families (12.1%, 4/33). These four mosaic variants, comprising three SNVs and one CNV, were identified in SOX10. The rate of parental mosaicism was 25% (4/16) in WS families with de novo SOX10 variants. The lowest allele ratio of a mosaic variant was 2.0% in parental saliva. These de novo WS cases were explained by parental mosaicism conferring an elevated recurrence risk in subsequent pregnancies of parents. Considering its importance in genetic counseling, low-level parental mosaicism should be systematically investigated by personalized sensitive testing. Amplicon-based NGS and ddPCR are recommended to detect and precisely quantify the mosaicism for SNPs and CNVs.


Assuntos
Mosaicismo , Síndrome de Waardenburg , Humanos , Síndrome de Waardenburg/diagnóstico , Síndrome de Waardenburg/genética , Estudos Retrospectivos , Pais , Éxons , Mutação
8.
Mol Genet Genomic Med ; 11(3): e2103, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36373990

RESUMO

BACKGROUND: Myhre syndrome is a rare multisystem genetic disorder that is caused by de novo heterozygous gain-of-function variants in SMAD4. Patients with Myhre syndrome exhibit several phenotypes at different ages such as small size, autism, developmental delay, left-sided heart defects, and hearing loss and often have a characteristic facial appearance. The early clinical diagnosis of Myhre syndrome remains a major challenge, particularly in the first year of life. METHODS: A Chinese male infant with syndactyly of fingers, hypertelorism, short palpebral fissures, and short philtrum was enrolled into the ENT department of the Chinese PLA General Hospital. Whole exome sequencing analysis was used to detect the disease-causing variant. A literature review of Myhre syndrome was also performed. RESULTS: A recurrent de novo missense variant c.1498A > G p.I500V(p. Ile500Val) in SMAD4 was detected confirming the clinical diagnosis of Myhre syndrome at the age of 38 days. The infant appears to be the youngest reported case of Myhre syndrome. At 23-month follow-up, the affected infant has dysmorphic facial features, growth retardation, and previously undescribed complete syndactyly. Review the literatures noted several common features in Myhre syndrome patients including hearing loss (72.7%), characteristic facial features (26.0%-54.5%), finger and toe abnormalities (3.9%-48.1%), short stature (45.5%), and respiratory (30.0%) and cardiovascular problems (65.0%). CONCLUSIONS: Clinicians should have a low threshold to perform genetic testing on patients with features suggesting Myhre syndrome even in the first year of life. Although some individuals with Myhre syndrome have normal hearing, early onset or progressive hearing loss usually occur in one or both ears in most patients, with remarkable phenotypic heterogeneity. Syndactyly may be minor such as typical 2-3 toe involvement, or more complicated as was observed in our patient.


Assuntos
Surdez , Perda Auditiva , Deficiência Intelectual , Sindactilia , Humanos , Masculino , Transtornos do Crescimento/genética , Deficiência Intelectual/genética , Recém-Nascido
9.
Am J Med Genet A ; 191(1): 183-189, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36369738

RESUMO

Coffin-Siris syndrome (CSS, OMIM#135900) is a rare congenital disorder associated with neurodevelopmental and dysmorphic features. The primary cause of CSS is pathogenic variants in any of 9 BAF chromatin-remodeling complex encoding genes or the genes SOX11 and PHF6. Herein, we performed whole-exome sequencing (WES) and a series of analyses of growth-related, auditory, and radiological findings in two probands with syndromic sensorineural hearing loss and inner ear malformations who exhibited distinctive facial features, intellectual disability, growth retardation, and fifth finger malformation. Two de novo variants in the SOX11 gene (c.148A>C:p.Lys50Asn; c.811_814del:p.Asn271Serfs*10) were detected in these probands and were identified as pathogenic variants as per ACMG guidelines. These probands were diagnosed as having CSS based upon clinical and genetic findings. This is the first report of CSS caused by variants in SOX11 gene in Chinese individuals. Deleterious SOX11 variants can result in sensorineural hearing loss with inner ear malformation, potentially extending the array of phenotypes associated with these pathogenic variants. We suggest that both genetic and clinical findings be considered when diagnosing syndromic hearing loss.


Assuntos
Deformidades Congênitas da Mão , Perda Auditiva Neurossensorial , Deficiência Intelectual , Micrognatismo , Humanos , Micrognatismo/diagnóstico , Micrognatismo/genética , Deformidades Congênitas da Mão/diagnóstico , Deformidades Congênitas da Mão/genética , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Pescoço/anormalidades , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/genética , Fatores de Transcrição SOXC/genética
10.
BMC Med Genomics ; 15(1): 241, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36401330

RESUMO

Pathogenic variants in MYO15A are known to cause autosomal recessive nonsyndromic hearing loss (ARNSHL), DFNB3. We have previously reported on one ARNSHL family including two affected siblings and identified MYO15A c.5964+3G > A and c.8375 T > C (p.Val2792Ala) as the possible deafness-causing variants. Eight year follow up identified one new affected individual in this family, who also showed congenital, severe to profound sensorineural hearing loss. By whole exome sequencing, we identified a new splice-site variant c.5531+1G > C (maternal allele), in a compound heterozygote with previously identified missense variant c.8375 T > C (p.Val2792Ala) (paternal allele) in MYO15A as the disease-causing variants. The new affected individual underwent unilateral cochlear implantation at the age of 1 year, and 5 year follow-up showed satisfactory speech and language outcomes. Our results further indicate that MYO15A-associated hearing loss is good candidates for cochlear implantation, which is in accordance with previous report. In light of our findings and review of the literatures, 58 splice-site variants in MYO15A are correlated with a severe deafness phenotype, composed of 46 canonical splice-site variants and 12 non-canonical splice-site variants.


Assuntos
Surdez , Perda Auditiva , Humanos , Linhagem , Miosinas/genética , Surdez/genética , Perda Auditiva/genética , Fenótipo , Família , Genótipo
11.
Stem Cell Res ; 62: 102831, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35691110

RESUMO

Mutations of SOX10 result in Waardenburg syndrome characterized by sensorineural hearing loss and pigmentary abnormalities, which can be found in association with a defect of migrating neural crest cells. The role of SINE-VNTR-Alu (SVA) retrotransposon insertions in disorders has only been minimally explored and there have been no reports of WS cases related to SVA retrotransposons. Here, we report the successful establishment and characterization of an iPSC line from a patient diagnosed with Waardenburg syndrome carrying an insertion of SVA in intron 2 of SOX10.


Assuntos
Células-Tronco Pluripotentes Induzidas , Síndrome de Waardenburg , Heterozigoto , Humanos , Mutação , Retroelementos/genética , Fatores de Transcrição SOXE/genética , Síndrome de Waardenburg/diagnóstico , Síndrome de Waardenburg/genética
12.
Comput Intell Neurosci ; 2022: 5738404, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401737

RESUMO

Rapid development of the Internet has contributed to the widespread adoption of social network platforms. Network media plays an important role in the process of public opinion dissemination and bears significant social responsibility. Public opinion mining is of great significance for online media to improve the quality of content provision and enhance media credibility. How to make full use of user-generated content is the key to improving the accuracy of position detection tasks. In this paper, we proposed a stance detection model based on user feature fusion by using comments of netizens in false news events on Weibo as research content. The method of feature fusion is adopted to integrate vectors including user sentiment, cognitive features, and text feature at the feature layer for model training and position prediction. The model is evaluated on a dataset of related microblog comments in false news. The result shows that our proposed method has a certain improvement in the effect of stance detection.


Assuntos
Opinião Pública , Mídias Sociais
13.
Nanomicro Lett ; 12(1): 138, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34138125

RESUMO

Highly thermo-conductive aqueous medium is a crucial premise to demonstrate high-performance thermal-related applications. Graphene has the diamond comparable thermal conductivity, while the intrinsic two-dimensional reality will result in strong anisotropic thermal conductivity and wrinkles or even crumples that significantly sacrifices its inherent properties in practical applications. One strategy to overcome this is to use three-dimensional (3D) architecture of graphene. Herein, 3D graphene structure with covalent-bonding nanofins (3D-GS-CBF) is proposed, which is then used as the filler to demonstrate effective aqueous medium. The thermal conductivity and thermal conductivity enhancement efficiency of 3D-GS-CBF (0.26 vol%) aqueous medium can be as high as 2.61 W m-1 K-1 and 1300%, respectively, around six times larger than highest value of the existed aqueous mediums. Meanwhile, 3D-GS-CBF can be stable in the solution even after 6 months, addressing the instability issues of conventional graphene networks. A multiscale modeling including non-equilibrium molecular dynamics simulations and heat conduction model is applied to interpret experimental results. 3D-GS-CBF aqueous medium can largely improve the solar vapor evaporation rate (by 1.5 times) that are even comparable to the interfacial heating system; meanwhile, its cooling performance is also superior to commercial coolant in thermal management applications.

14.
J Phys Chem Lett ; 8(15): 3703-3710, 2017 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-28742361

RESUMO

The chemical nature of electrolytes has been demonstrated to play a pivotal role in the charge storage of electric double-layer capacitors (EDLCs), whereas primary mechanisms are still partially resolved but controversial. In this work, a systematic exploration into EDL structures and kinetics of representative aqueous electrolytes is performed with numerical simulation and experimental research. Unusually, a novel charging mechanism exclusively predominated by kinetics is recognized, going beyond traditional views of manipulating capacitances preferentially via interfacial structural variations. Specifically, strikingly distinctive EDL structures stimulated by diverse ion sizes, valences, and mixtures manifest a virtually identical EDL capacitance, where the dielectric nature of solvents attenuates ionic effects on electrolyte redistributions, in stark contradiction with solvent-free counterpart and traditional Helmholtz theory. Meanwhile, corresponding kinetics evolve conspicuously with ionic species, intimately correlated with ion-solvent interactions. The achieved mechanisms are subsequently illuminated by electrochemical measurements, highlighting the crucial interplay between ions and solvents in regulating EDLC performances.

15.
Ecol Evol ; 7(12): 4456-4464, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28649355

RESUMO

Shennongjia Rhinopithecus roxellana (SNJ R. roxellana) is the smallest geographical population of R. roxellana. The phylogenetic relationships among its genera and species and the biogeographic processes leading to their current distribution are largely unclear. To address these issues, we resequenced and obtained a new, complete mitochondrial genome of SNJ R. roxellana by next-generation sequencing and standard Sanger sequencing. We analyzed the gene composition, constructed a phylogenetic tree, inferred the divergence ages based on complete mitochondrial genome sequences, and analyzed the genetic divergence of 13 functional mtDNA genes. The phylogenetic tree and divergence ages showed that R. avunculus (the Tonkin snub-nosed monkey) was the first to diverge from the Rhinopithecus genus ca. 2.47 million years ago (Ma). Rhinopithecus bieti and Rhinopithecus strykeri formed sister groups, and the second divergence from the Rhinopithecus genus occurred ca. 1.90 Ma. R. roxellana and R. brelichi diverged from the Rhinopithecus genus third, ca. 1.57 Ma. SNJ R. roxellana was the last to diverge within R. roxellana species in 0.08 Ma, and the most recent common ancestor of R. roxellana is 0.10 Ma. The analyses on gene composition showed SNJ R. roxellana was the newest geographic population of R. roxellana. The work will help to develop a more accurate protection policy for SNJ R. roxellana and facilitate further research on selection and adaptation of R. roxellana.

16.
Phys Chem Chem Phys ; 19(11): 7678-7688, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28256645

RESUMO

The behavior of ion diffusion in nano-confined spaces and its temperature dependence provide important fundamental information about electric double-layer capacitors (EDLCs) employing nano-sized active materials. In this work, the ion diffusion coefficients of NaCl electrolyte confined within neutral and charged graphene nanochannels at different temperatures are investigated using molecular dynamics simulations. The results show that ions confined in neutral nanochannels diffuse faster (along the graphene surfaces) than those in bulk solution, which could be attributed to the relatively smaller concentration in confined spaces and the solvophobic nature of graphene surfaces. In charged nanochannels where the electrostatic interactions between counter-ions and charged channel surfaces govern the motion of ions, the diffusion coefficients are found to be lower than those in the neutral counterparts. The increase of temperature will lead to enhanced vibrant thermal motion of ions. Due to the significant role of ion-surface interactions, ion diffusion coefficients in nano-confined spaces are more stable, that is, insensitive to the temperature variation, than those in bulk solution. The electrical conductivity is further estimated using the Nernst-Einstein equation. The findings of the current work could provide basic data and information for research studies on the thermal effects of graphene-based EDLCs.

17.
J Phys Chem Lett ; 8(1): 153-160, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27973849

RESUMO

Multilayer graphenes have been widely used as active materials for electric double-layer capacitors (EDLCs), where their numerous edges are demonstrated to play a crucial role in charge storage. In this work, the interfacial structure and capacitive behaviors of multilayer graphene edges with representative interlayer spacing are studied via molecular dynamics (MD) simulations. Compared with planar graphite surfaces, edges can achieve a 2-fold increase in the specific capacitance at a wider interlayer spacing of ∼5.0 Å. Unusually, the molecular origins for achieved charge storage are predominantly attributed to the structural evolutions of solvents occurring in the double layer, going beyond the traditional views of regulating the capacitance by ion adsorption/separation. Specifically, diverse ionic distributions exhibit similar screening ability and EDLC thickness, while water molecules can counterbalance the interfacial electric fields more effectively at edge site. The as-obtained findings will be instructive in designing graphene-based EDLCs for advanced capacitive performances.

18.
Sci Rep ; 5: 14652, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26424365

RESUMO

Vertically-oriented graphenes (VGs) are promising active materials for electric double layer capacitors (EDLCs) due to their unique morphological and structural features. This study, for the first time, reports the molecular dynamics (MD) simulations on aqueous NaCl electrolytes confined within VG channels with different surface charge densities and channel widths. Simulation results show that the accessibility of ions and the structure of EDLCs are determined by the ion type/size, surface charging, and VG channel width. For relatively narrow VG channels with the same width, the threshold charge density (to compensate the energy penalty for shedding hydration shell) and the dehydration rate of Cl(-) ions are larger than those of Na(+) ions. To achieve the highest ion concentration coefficient, the effective VG channel width should be between the crystal and hydration diameters of the ions. The results are further quantified and elucidated by calculating the electrolyte density profiles. The molecular insights obtained in the current work are useful in guiding the design and fabrication of VGs for advancing their EDLC applications.

19.
Zhonghua Liu Xing Bing Xue Za Zhi ; 36(10): 1109-12, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26837355

RESUMO

OBJECTIVE: To understand the prevalence of informing doctors of the HIV infection status during medical care seeking and influential factors among people living with HIV/AIDS. METHODS: The study was conducted among people living with HIV/AIDS in 7 provinces in China, including those receiving HIV test, HIV counsel and HIV infection treatment. The data were analyzed with software SAS 9.2. Chi-square test was used to compare the informing rates in patients with different characteristics. Univariate and multivariate logistic regression analyses were conducted to identify the influential factors. RESULTS: Of the 2 432 HIV/AIDS patients, 49.7% (716/1 442) didn't inform the doctors of their HIV infection status actively. The non-active informing rate was 51.9% (559/1 077) in males, 62.9% (212/337) in age group 18-30 years old, 58.1% (555/955) in those with a educational level >primary school, 65.7% (241/367) in those working in private/joint companies or the self employed and 62.5% (197/315) in those living in small cities. The non active informing rate was highest in those infected through sexual contact (66.3%, 275/415). Multivariate logical regression analysis indicated that those infected through illegal blood donation would like to inform of the HIV infection status actively (OR=0.083, 95% CI: 0.049-0.141) , but those working in private/joint companies or the self employed would like not to inform of the HIV infection status actively (OR=1.531, 95% CI: 1.017-2.304). CONCLUSION: The non active informing rate of HIV infection status was high in people living with HIV/AIDS. It is necessary to conduct the targeted health education to encourage people living with HIV/AIDS to inform of their HIV infection status actively.


Assuntos
Síndrome da Imunodeficiência Adquirida , Comunicação , Infecções por HIV , Comportamentos Relacionados com a Saúde , Relações Médico-Paciente , Adolescente , Adulto , China , Doenças Transmissíveis , Feminino , Educação em Saúde , Humanos , Masculino , Programas de Rastreamento , Prevalência , Comportamento Sexual , Adulto Jovem
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