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1.
J Am Chem Soc ; 137(34): 11069-75, 2015 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26281006

RESUMO

Using Cu2ZnSn(S,Se)4 (CZTSSe) as a model system, we demonstrate the kinetic control of solid-gas reactions at nanoscale by manipulating the surface chemistry of both sol-gel nanoparticles (NPs) and colloidal nanocrystals (NCs). Specifically, we first identify that thiourea (commonly used as sulfur source in sol-gel processes for metal sulfides) can transform into melamine upon film formation, which serves as surface ligands for as-formed Cu2ZnSnS4 (CZTS) NPs. We further reveal that the presence of these surface ligands can significantly affect the outcome of the solid-gas reactions, which enables us to effectively control the selenization process during the fabrication of CZTSSe solar cells and achieve optimal film morphologies (continuous large grains) by fine-tuning the amount of surface ligands used. Such enhancement leads to better light absorption and allows us to achieve 6.5% efficiency from CZTSSe solar cells processed via a sol-gel process using nontoxic, low boiling point mixed solvents. We believe our discovery that the ligand of particulate precursors can significantly affect solid-gas reactions is universal to solid-state chemistry and will boost further research in both understanding the fundamentals of solid-state reactions at nanoscale and taking advantage of these reactions to fabricate crystalline thin film semiconductors with better morphologies and performances.

2.
J Ovarian Res ; 17(1): 74, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570862

RESUMO

OBJECTIVE: To comprehensively evaluate the effect of low birth weight on premature ovarian insufficiency. METHODS: We performed a systematic review of the literature by searching MEDLINE, EMBASE, Web of Science, Scopus, Wanfang and CNKI up to August 2023. All cohort and case-control studies that included birth weight as an exposure and premature ovarian insufficiency as an outcome were included in the analysis. Data were combined using inverse-variance weighted meta-analysis with fixed and random effects models and between-study heterogeneity evaluated. We evaluated risk of bias using the Newcastle Ottawa Scale and using Egger's method to test publication bias. All statistical analyses were performed with the use of R software. RESULTS: Five articles were included in the review. A total of 2,248,594 women were included, including 21,813 (1%) cases of premature ovarian insufficiency, 150,743 cases of low birth weight, and 220,703 cases of macrosomia. We found strong evidence that changed the results of the previous review that low birth weight is associated with an increased risk of premature ovarian insufficiency (OR = 1.15, 95%CI 1.09-1.22) in adulthood compared with normal birth weight. No effect of macrosomia on premature ovarian insufficiency was found. CONCLUSIONS: Our meta-analysis showed strong evidence of an association between low birth weight and premature ovarian insufficiency. We should reduce the occurrence of low birth weight by various methods to avoid the occurrence of premature ovarian insufficiency.

3.
Front Endocrinol (Lausanne) ; 14: 1238090, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900148

RESUMO

Objective: Type 2 diabetes mellitus (T2DM) is an endocrine-related disease with an increasing incidence worldwide. Male sexual dysfunction is common in diabetic patients. Therefore, we designed a Mendelian randomization (MR) study to investigate the association of type 2 diabetes and 3 glycemic traits with testosterone levels. Methods: Uncorrelated single nucleotide polymorphisms (SNPs) associated with T2DM (N = 228), fasting insulin (N = 38), fasting glucose (N = 71), and HbA1c (N = 75) at the genome-wide significance were selected as instrument variables. Genetic associations with testosterone levels (total testosterone, TT, bioavailable testosterone, BT, and sex hormone-binding globulin, SHBG) were obtained from the UK Biobank studies and other large consortia. Two-sample MR analysis was used to minimize the bias caused by confounding factors and response causality. Multivariable MR analysis was performed using Body mass index (BMI), Triglycerides (TG), LDL cholesterol (LDL), and adiponectin to adjust for the effects of potential confounders. Results: Type 2 diabetes mellitus was associated with the decrease of total testosterone (ß: -0.021,95%CI: -0.032, -0.010, p<0.001) and sex hormone binding globulin (ß: -0.048,95%CI: -0.065, -0.031, p<0.001). In males, total testosterone (ß: 0.058, 95% CI: 0.088, 0.028, p < 0.001) decreased. In females, it was associated with an increase in bioavailable testosterone (ß: 0.077,95%CI: 0.058,0.096, p<0.001). Each unit (pmol/L) increase in fasting insulin was associated with 0.283nmol/L decrease in sex hormone-binding globulin (95%CI: -0.464, -0.102, p=0.002) and 0.260nmol/L increase in bioavailable testosterone (95%CI: -0.464, -0.102, p= 0.002). In males, sex hormone binding globulin decreased by 0.507nmol/L (95%CI: -0.960, -0.054, p= 0.028) and bioavailable testosterone increased by 0.216nmol/L (95%CI: 0.087,0.344, p= 0.001). In females, sex hormone binding globulin decreased by 0.714 nmol/L (95%CI: -1.093, -0.335, p<0.001) and bioavailable testosterone increased by 0.467nmol/L (95%CI: 0.286,0.648, p<0.001). Each unit (%) increase in HbA1c was associated with 0.060nmol/L decrease in sex hormone-binding globulin (95%CI: -0.113, -0.007, p= 0.026). In males, total testosterone decreased by 0.171nmol/L (95%CI: -0.288, -0.053, p=0.005) and sex hormone binding globulin decreased by 0.206nmol/L (95%CI: -0.340, -0.072, p=0.003). Total testosterone increased by 0.122nmol/L (95%CI: 0.012,0.233, p=0.029) and bioavailable testosterone increased by 0.163nmol/L (95%CI: 0.042,0.285, p=0.008) in females. Conclusions: Using MR Analysis, we found independent effects of type 2 diabetes, fasting insulin, and HbA1c on total testosterone and sex hormone-binding globulin after maximum exclusion of the effects of obesity, BMI, TG, LDL and Adiponectin.


Assuntos
Diabetes Mellitus Tipo 2 , Feminino , Humanos , Masculino , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/epidemiologia , Globulina de Ligação a Hormônio Sexual/metabolismo , Hemoglobinas Glicadas , Adiponectina/metabolismo , Análise da Randomização Mendeliana , Testosterona , Insulina/metabolismo , Triglicerídeos
4.
Toxics ; 11(12)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38133388

RESUMO

Biofilms that colonize on the surface of microplastics (MPs) in freshwaters may pose a potential health risk. This study examined factors that influence MP-associated biofilm growth, including polymer type, degree of weathering, and source water quality. Weathered MPs produced in-lab were employed in biofilm trials conducted on site using a passive flow-through system with raw water at drinking water treatment facility intakes. Adenosine triphosphate (ATP) was used to quantify biofilm abundance; biofilm composition was assessed via metagenomic sequencing. Biofilm growth was observed on all polymer types examined and most prevalent on polyvinyl chloride (PVC), where ATP levels were 6 to 12 times higher when compared to other polymers. Pathogen-containing species including Salmonella enterica and Escherichia coli were present on all polymers with relative abundance up to 13.7%. S. enterica was selectively enriched on weathered MPs in specific water matrices. These findings support the need to research the potential accumulation of pathogenic organisms on microplastic surfaces.

5.
J Am Chem Soc ; 134(11): 5010-3, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22329720

RESUMO

We report a new platform for design of soluble precursors for CuInSe(2) (CIS), Cu(In(1-x)Ga(x))Se(2) (CIGS), and Cu(2)ZnSn(S,Se)(4) (CZTS) phases for thin-film potovoltaics. To form these complex phases, we used colloidal nanocrystals (NCs) with metal chalcogenide complexes (MCCs) as surface ligands. The MCC ligands both provided colloidal stability and represented essential components of target phase. To obtain soluble precursors for CuInSe(2), we used Cu(2-x)Se NCs capped with In(2)Se(4)(2-) MCC surface ligands or CuInSe(2) NCs capped with {In(2)Cu(2)Se(4)S(3)}(3-) MCCs. A mixture of Cu(2-x)Se and ZnS NCs, both capped with Sn(2)S(6)(4-) or Sn(2)Se(6)(4-) ligands was used for solution deposition of CZTS films. Upon thermal annealing, the inorganic ligands reacted with NC cores forming well-crystallized pure ternary and quaternary phases. Solution-processed CIS and CZTS films featured large grain size and high phase purity, confirming the prospects of this approach for practical applications.

6.
J Am Chem Soc ; 134(3): 1583-90, 2012 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-22148506

RESUMO

The optical properties of stoichiometric copper chalcogenide nanocrystals (NCs) are characterized by strong interband transitions in the blue part of the spectral range and a weaker absorption onset up to ~1000 nm, with negligible absorption in the near-infrared (NIR). Oxygen exposure leads to a gradual transformation of stoichiometric copper chalcogenide NCs (namely, Cu(2-x)S and Cu(2-x)Se, x = 0) into their nonstoichiometric counterparts (Cu(2-x)S and Cu(2-x)Se, x > 0), entailing the appearance and evolution of an intense localized surface plasmon (LSP) band in the NIR. We also show that well-defined copper telluride NCs (Cu(2-x)Te, x > 0) display a NIR LSP, in analogy to nonstoichiometric copper sulfide and selenide NCs. The LSP band in copper chalcogenide NCs can be tuned by actively controlling their degree of copper deficiency via oxidation and reduction experiments. We show that this controlled LSP tuning affects the excitonic transitions in the NCs, resulting in photoluminescence (PL) quenching upon oxidation and PL recovery upon subsequent reduction. Time-resolved PL spectroscopy reveals a decrease in exciton lifetime correlated to the PL quenching upon LSP evolution. Finally, we report on the dynamics of LSPs in nonstoichiometric copper chalcogenide NCs. Through pump-probe experiments, we determined the time constants for carrier-phonon scattering involved in LSP cooling. Our results demonstrate that copper chalcogenide NCs offer the unique property of holding excitons and highly tunable LSPs on demand, and hence they are envisaged as a unique platform for the evaluation of exciton/LSP interactions.

7.
Integr Psychol Behav Sci ; 56(2): 355-367, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34699019

RESUMO

In this paper, I examine a Chinese family's oral history, which revolves around their tumultuous life transformations under the impact of China's communist movement between 1940 and 1977. Using interviews with four siblings who have distinctive personalities and life narratives, I focus on how they apply fatalistic thinking-a phenomenon popular among ordinary Chinese but is rarely analyzed by scholars-to make sense of the vicissitudes of the fates of the family members. I position the Chinese family's oral history in macro and micro contexts. In the macro context, since the land reform in 1940s, the Chinese Communist Party (CCP) had attempted to replace peasants' fatalistic thinking with class analysis to explain the roots of hardships in their lives. As the communist movement and class struggle receded, fatalistic thinking-which has never been eradicated-revived. In the micro context, fatalistic thinking is expressed through distinctive memories and narratives, which are linked to personalities and identities. I argue that fatalistic thinking is a mean of self-construction that people consciously or unconsciously resort to when facing absurdity. By using fatalistic thinking, people develop narratives about the self and create a sense of mental balance.


Assuntos
Comunismo , População Rural , China , Humanos
8.
Medicine (Baltimore) ; 101(21): e29171, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35623067

RESUMO

BACKGROUND: Several studies have reported positive therapeutic effects of electroacupuncture, warm needling, or a combination of the 2 for heel pain; however, the quality of the evidence is limited by methodological limitations. Given that there are no high-quality meta-analyses or reviews incorporating the available evidence, the aim of this study was to systematically review the level I evidence in the literature to determine whether a combination of electroacupuncture and warm needling therapy is more beneficial than acupuncture alone in patients with plantar heel pain syndrome. METHODS: From the inception to May 2022, the Wanfang, CNKI, EMBASE, PubMed, Web of Science, and Cochrane Library electronic databases will be searched using the key phrases "acupuncture", "warm needling", "electroacupuncture", "heel pain", "plantar pain", and "prospective" for all relevant studies. The outcomes include pain, physical disability, plantar fascia thickness, and foot functional status. Quality assessment of all studies included in this review will be independently assessed by 2 reviewers using the Cochrane Collaborations tool. We consider significant heterogeneity between trials if I2 > 50%, and severe heterogeneity if I2 > 75%. When significant heterogeneity is indicated, we will find the source of heterogeneity by subgroup or sensitivity analysis. RESULTS: The results of our review will be reported strictly following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines and the recommendations of the Cochrane Collaboration. CONCLUSIONS: We initially hypothesized that combination therapy would lead to better treatment outcomes.Registration number: 10.17605/OSF.IO/VWBYJ.


Assuntos
Eletroacupuntura , Doenças do Pé , Eletroacupuntura/efeitos adversos , Eletroacupuntura/métodos , Doenças do Pé/terapia , Calcanhar , Humanos , Metanálise como Assunto , Dor , Literatura de Revisão como Assunto , Síndrome , Revisões Sistemáticas como Assunto
9.
Front Plant Sci ; 13: 873621, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35615118

RESUMO

A bacterial strain JI39 that had plant growth-promoting traits was isolated from the rhizosphere soil of Panax ginseng. It had the ability to produce high indole-3-acetic acid (13.1 µg/ml), phosphate solubilization (164.2 µg/ml), potassium solubilization (16.1 µg/ml), and nitrogen fixation. The strain JI39 was identified to be Arthrobacter nicotinovorans based on morphological, physiological, and biochemical traits and through 16S rDNA sequence analysis. The optimal culture environment for strain growth was 1.0% NaCl, 30°C, pH 6.0, and without UV irradiation. The strain can produce cellulase and protease. The strain JI39 can significantly promote the growth of ginseng. After ginseng seeds were treated with 3 × 108 CFU/ml of JI39 bacterial suspension, the shoot's length was significantly increased by 64.61% after 15 days. Meanwhile, the fresh weight of 2-year-old ginseng roots was significantly increased by 24.70% with a treatment by the 108 CFU/ml bacterial suspension after 150 days in the field. The gene expression of phenylalanine ammonia-lyase (PAL), ß-1.3 glucanase (ß-1,3-GA), chitinase (CHI), superoxide dismutase (SOD), and peroxidase (POD) of ginseng was upregulated, and it also can improve the soil urease, phosphatase, invertase, and catalase activity. In conclusion, the bacterial strain JI39 could efficiently promote the growth of ginseng and has the potential to be a good microbial fertilizer for ginseng.

10.
Mol Med Rep ; 12(2): 2912-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25955216

RESUMO

Autophagy is an evolutionarily conserved response that can be activated in response to heavy metal. Thus, the present study investigated the effect of autophagy on neurotoxic damage caused by cadmium (Cd) in rat cerebral cortical neurons. The results indicated that the viability of cortical neurons treated with Cd was markedly decreased in a dose-and time-dependent manner. The present study provided evidence that cortical neurons treated with Cd underwent autophagy: The conversion of microtubule-associated protein 1A/1B-light chain 3 (LC3) to LC3-II, an increase in the punctate distribution of endogenous LC3-II and the presence of autophagosomes were identified. Combined treatment with Cd and chloroquine, an autophagy inhibitor, reduced the amount of autophagocytosis and cell activity, whereas rapamycin, an autophagy inducer, reduced Cd-mediated cytotoxicity. Furthermore, it was found that beclin-1 and class III phosphoinositide 3 kinase (PI3K) levels were increased, while levels of the anti-apoptotic protein B-cell lymphoma 2 (Bcl-2) were decreased after Cd treatment. LY294002, a specific inhibitor of PI3K, prevented the decline in Bcl-2 production and the increase in levels of beclin-1, class III PI3K and autophagy following Cd treatment. In conclusion, the results of the present study suggested that Cd can induce cytoprotective autophagy by activating the class III PI3K/beclin-1/Bcl-2 signaling pathway, and that the autophagy pathway can serve as a sensitive biomarker for nervous system injury after exposure to Cd.


Assuntos
Autofagia/efeitos dos fármacos , Cádmio/toxicidade , Córtex Cerebral/citologia , Neurônios/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1 , Células Cultivadas , Cloroquina/toxicidade , Cromonas/farmacologia , Embrião de Mamíferos/citologia , Feminino , Microscopia de Fluorescência , Proteínas Associadas aos Microtúbulos/metabolismo , Morfolinas/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley
11.
ACS Nano ; 8(9): 9164-72, 2014 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-25106060

RESUMO

A fully solution-processed high performance Cu2ZnSn(S,Se)4 (CZTSSe, kesterite) device has been demonstrated. It is based on the rational engineering of elemental spatial distributions in the bulk and particularly near the surface of the film from nanocrystal precursors. The nanocrystals are synthesized through a modified colloidal approach, with excellent solubility over a large compositional window, followed by a selenization process to form the absorber. The X-ray photoluminescence (XPS) depth profiling indicates an undesirable Sn-rich surface of the selenized film. An excessive Zn species was quantitatively introduced through nanocrystals precursor to correct the element distribution, and accordingly a positive correlation between the spatial composition in the bulk/surface film and the resulting device parameter is established. The enhanced device performance is associated with the reduced interfacial recombination. With a Zn content 1.6 times more than the stoichiometry; the optimized device, which is fabricated by employing a full solution process from the absorber to the transparent top electrode, demonstrates a performance of 8.6%. This composition-control approach through stoichiometric adjustments of nanocrystal precursors, and the developed correlation between the spatial composition and device performance may also benefit other multielement-based photovoltaics.

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