112 research outputs found
Metal adsorption by quasi cellulose xanthogenates derived from aquatic and terrestrial plant materials
The FTIR spectra, SEM-EDXA and copper adsorption capacities of the raw plant materials, alkali treated straws and cellulose xanthogenate derivatives of Eichhornia crassipes shoot, rape straw and corn stalk were investigated. FTIR spectra indicated that of the three plant materials, the aquatic biomass of Eichhornia crassipes shoot contained more O-H and C=O groups which accounted for the higher Cu²⁺ adsorption capacities of the raw and alkali treated plant material. SEM-EDXA indicated the incorporation of sulphur and magnesium in the cellulose xanthogenate. The Cu²⁺ adsorption capacities of the xanthogenates increased with their magnesium and sulphur contents. However more copper was adsorbed than that can be explained by exchange of copper with magnesium. Precipitation may contribute to the enhanced uptake of copper by the cellulose xanthogenate
Trends in Hospital Admissions Due to Antidepressant-Related Adverse Drug Events from 2001 to 2011 in the U.S.
BACKGROUND: Depression is a prevalent mental health disorder and the fourth leading cause of disability in the world as per the World Health Organization. Use of antidepressants can lead to adverse drug events (ADEs), defined as any injury resulting from medication use. This study aimed to examine changes in hospital admissions due to antidepressant-related ADEs (ArADEs) among different socio-demographic groups and changes in lengths of stay (LOS) and hospital charges in ArADE admissions from 2001 to 2011.
METHODS: The Healthcare Cost and Utilization Project database was used. ArADE admissions in different socio-demographic groups were examined including characteristics such as age, gender, rural/urban, and income. LOS and hospital charges for ArADE cases were compared between 2001 and 2011. Chi-square test and t test were used for statistical analyses.
RESULTS: There were 17,375 and 20,588 ArADE related admissions in 2001 and 2011, respectively. There was a 17.6% increase among the group of 18 to 64 years old and a 64.8% increase among the group of 65 years or older while the other age groups experienced decreased admission rates. Males and females had similar increases. Patients from the lower income areas experienced a two-fold increase while those from the higher income areas experienced a decrease. The mean LOS for all ArADE related admissions increased from 2.18 to 2.81 days and mean hospital charges increased from 21,572.5.
CONCLUSIONS: There was an increase in ArADE hospital admissions. The greater increase in ArADE admissions among elderly, urban or low-income patients should be noted and addressed by practitioners and policy makers. The large increase in hospital charges needs further research
JWA Deficiency Suppresses Dimethylbenz[a]Anthracene-Phorbol Ester Induced Skin Papillomas via Inactivation of MAPK Pathway in Mice
Our previous studies indicated that JWA plays an important role in DNA damage repair, cell migration, and regulation of MAPKs. In this study, we investigated the role of JWA in chemical carcinogenesis using conditional JWA knockout (JWAΔ2/Δ2) mice and two-stage model of skin carcinogenesis. Our results indicated that JWAΔ2/Δ2 mice were resistant to the development of skin papillomas initiated by 7, 12-dimethylbenz(a)anthracene (DMBA) followed by promotion with 12-O-tetradecanoylphorbol-13-acetate (TPA). In JWAΔ2/Δ2 mice, the induction of papilloma was delayed, and the tumor number and size were reduced. In primary keratinocytes from JWAΔ2/Δ2 mice, DMBA exposure induced more intensive DNA damage, while TPA-promoted cell proliferation was reduced. The further mechanistic studies showed that JWA deficiency blocked TPA-induced activation of MAPKs and its downstream transcription factor Elk1 both in vitro and in vivo. JWAΔ2/Δ2 mice are resistance to tumorigenesis induced by DMBA/TPA probably through inhibition of transcription factor Elk1 via MAPKs. These results highlight the importance of JWA in skin homeostasis and in the process of skin tumor development
Regulating Cytoplasmic Calcium Homeostasis Can Reduce Aluminum Toxicity in Yeast
Our previous study suggested that increased cytoplasmic calcium (Ca) signals may mediate aluminum (Al) toxicity in yeast (Saccharomyces cerevisiae). In this report, we found that a yeast mutant, pmc1, lacking the vacuolar calcium ion (Ca2+) pump Ca2+-ATPase (Pmc1p), was more sensitive to Al treatment than the wild-type strain. Overexpression of either PMC1 or an anti-apoptotic factor, such as Bcl-2, Ced-9 or PpBI-1, decreased cytoplasmic Ca2+ levels and rescued yeast from Al sensitivity in both the wild-type and pmc1 mutant. Moreover, pretreatment with the Ca2+ chelator BAPTA-AM sustained cytoplasmic Ca2+ at low levels in the presence of Al, effectively making the cells more tolerant to Al exposure. Quantitative RT-PCR revealed that the expression of calmodulin (CaM) and phospholipase C (PLC), which are in the Ca2+ signaling pathway, was down-regulated under Al stress. This effect was largely counteracted when cells overexpressed anti-apoptotic Ced-9 or were pretreated with BAPTA-AM. Taken together, our results suggest that the negative regulation of Al-induced cytoplasmic Ca signaling is a novel mechanism underlying internal resistance to Al toxicity
Research on the development law of karst caves on water conducting fractures under the influence of mining in Southwest Karst Mining Areas
Southwest Guizhou mining area is a typical karst development mining area in China. Under the influence of mining, the height of karst roof water conducting cracks is abnormally developed. During the rainy season, atmospheric precipitation is extremely easy to enter the underground working face through ultra-high water conducting channels, causing water inrush disasters at the working face, seriously affecting the normal production of the mine. Therefore, based on the analysis of the occurrence characteristics of karst caves in Xintian Coal Mine, the development rules of karst roof water conducting fracture zones during mining were studied by means of on-site measurement, indoor simulation, and theoretical analysis. The development mechanism of ultra-high water conducting fractures was revealed. The results show that: ①The roof karst caves in the study area have obvious zonation phenomenon from top to bottom in the layers such as the surface, the Yulongshan section, and the Changxing Formation. The surface water holes develop along the gullies, and the karst caves in the upper and middle parts of the strong aquifer in the Yulongshan section develop, presenting different forms of beads. The Changxing Formation only locally hosts karst caves with smaller diameters; ② Karst caves in karst aquifers have an important impact on water conducting fractures. Without karst caves, the development height of water conducting fractures is 43.1 m, and the fracture mining ratio is 14.4. Under karst caves, the development of water conducting fractures is abnormal, with a height of 173.1 m, and a fracture mining ratio of 57.7, which communicates with the strong limestone aquifer in the Yulong Mountain section; ③ Karst roof water conducting fissures consist of two parts: mining upward fissures and karst cave instability downward fissures. Under the influence of mining, karst caves become unstable under the combined action of concentrated stress and mining additional stress, and are prone to form downward fissures, which communicate with mining upward fissures, ultimately forming a special ultra-high water conducting fissure in southwestern Guizhou mining area
Cloning and Comparative Studies of Seaweed Trehalose-6-Phosphate Synthase Genes
The full-length cDNA sequence (3219 base pairs) of the trehalose-6-phosphate synthase gene of Porphyra yezoensis (PyTPS) was isolated by RACE-PCR and deposited in GenBank (NCBI) with the accession number AY729671. PyTPS encodes a protein of 908 amino acids before a stop codon, and has a calculated molecular mass of 101,591 Daltons. The PyTPS protein consists of a TPS domain in the N-terminus and a putative TPP domain at the C-terminus. Homology alignment for PyTPS and the TPS proteins from bacteria, yeast and higher plants indicated that the most closely related sequences to PyTPS were those from higher plants (OsTPS and AtTPS5), whereas the most distant sequence to PyTPS was from bacteria (EcOtsAB). Based on the identified sequence of the PyTPS gene, PCR primers were designed and used to amplify the TPS genes from nine other seaweed species. Sequences of the nine obtained TPS genes were deposited in GenBank (NCBI). All 10 TPS genes encoded peptides of 908 amino acids and the sequences were highly conserved both in nucleotide composition (>94%) and in amino acid composition (>96%). Unlike the TPS genes from some other plants, there was no intron in any of the 10 isolated seaweed TPS genes
A hydrated deep eutectic electrolyte with finely-tuned solvation chemistry for high-performance zinc-ion batteries
Despite their cost-effectiveness and intrinsic safety, aqueous zinc-ion batteries have faced challenges with poor reversibility originating from various active water-induced side reactions. After systematically scrutinizing the effects of water on the evolution of solvation structures, electrolyte properties, and electrochemical performances through experimental and theoretical approaches, a hydrated deep eutectic electrolyte with a water-deficient solvation structure ([Zn(H2O)2(eg)2(otf)2]) and reduced free water content in the bulk solution is proposed in this work. This electrolyte can dramatically suppress water-induced side reactions and provide high Zn2+ mass transfer kinetics, resulting in highly reversible Zn anodes (∼99.6% Coulombic efficiency over 1000 cycles and stable cycling over 4500 h) and high capacity Zn//NVO full cells (436 mA h g−1). This work will aid the understanding of electrolyte solvation structure–electrolyte property–electrochemical performance relationships of aqueous electrolytes in aqueous zinc-ion batteries
Metal–organic frameworks and their derivatives for optimizing lithium metal anodes
Lithium metal anodes (LMAs) have been considered the ultimate anode materials for next-generation batteries. However, the uncontrollable lithium dendrite growth and huge volume expansion that can occur during charge and discharge seriously hinder the practical application of LMAs. Metal–organic framework (MOF) materials, which possess the merits of huge specific surface area, excellent porosity, and flexible composition/structure tunability, have demonstrated great potential for resolving both of these issues. This article first explores the mechanism of lithium dendrite formation as described by four influential models. Subsequently, based on an in-depth understanding of these models, we propose potential strategies for utilizing MOFs and their derivatives to suppress lithium dendrite growth. We then provide a comprehensive review of research progress with respect to various applications of MOFs and their derivatives to suppress lithium dendrites and inhibit volume expansion. The paper closes with a discussion of perspectives on future modifications of MOFs and their derivatives to achieve stable, dendrite-free lithium metal batteries
Trace Amounts of Triple-Functional Additives Enable Reversible Aqueous Zinc-Ion Batteries from a Comprehensive Perspective
Although their cost-effectiveness and intrinsic safety, aqueous zinc-ion batteries suffer from notorious side reactions including hydrogen evolution reaction, Zn corrosion and passivation, and Zn dendrite formation on the anode. Despite numerous strategies to alleviate these side reactions have been demonstrated, they can only provide limited performance improvement from a single aspect. Herein, a triple-functional additive with trace amounts, ammonium hydroxide, was demonstrated to comprehensively protect zinc anodes. The results show that the shift of electrolyte pH from 4.1 to 5.2 lowers the HER potential and encourages the in situ formation of a uniform ZHS-based solid electrolyte interphase on Zn anodes. Moreover, cationic NH4+ can preferentially adsorb on the Zn anode surface to shield the "tip effect" and homogenize the electric field. Benefitting from this comprehensive protection, dendrite-free Zn deposition and highly reversible Zn plating/stripping behaviors were realized. Besides, improved electrochemical performances can also be achieved in Zn//MnO2 full cells by taking the advantages of this triple-functional additive. This work provides a new strategy for stabilizing Zn anodes from a comprehensive perspective
Work-family conflict and its related factors among emergency department physicians in China: A national cross-sectional study
BackgroundWork-family conflict is common among emergency department physicians. Identifying the factors associated with work-family conflict is key to reducing its negative impact on mental health and work attitudes. However, the work-family conflict of Chinese emergency department physicians and the related factors have been scarcely studied.ObjectiveThis study aimed to investigate the current status and related factors of work-family conflict among Chinese emergency department physicians.MethodsA national cross-sectional study was conducted among emergency department physicians in China from June 2018 to August 2018. A standard questionnaire was used to investigate the demographic characteristics, work-related factors, and work-family conflict of emergency department physicians. The generalized linear regression analysis was used to identify the related factors of work-family conflict.ResultsA total of 10,457 licensed emergency department physicians participated in the study. The average score of work-family conflict among the enrolled emergency department physicians was 19.27 ± 3.94, and the prevalence of high levels of work-family conflict was 69.19%. The multivariable regression analysis showed that emergency physicians who were female (linear regression coefficient, −0.25; SE, 0.08; P = 0.002), older than 40 years (linear regression coefficient,−0.53; SE, 0.14; P < 0.001), and earning more than 4,000 CNY per month (e.g., 4,001~6,000 vs. ≤4,000 CNY: linear regression coefficient, −0.17; SE, 0.09; P = 0.04) had lower work-family conflicts. However, emergency department physicians who were married (linear regression coefficient, 0.37; SE, 0.11; P < 0.001), highly educated (linear regression coefficient, 0.46; SE, 0.10; P < 0.001), had a high technical title (e.g., intermediate vs. junior technical title: linear regression coefficient, 0.61; SE, 0.09; P < 0.001), worked in a high-grade hospital (e.g., tertiary hospital vs. emergency center: linear regression coefficient, 0.38; SE, 0.11; P < 0.001), had a higher frequency of night shifts (e.g., 6~10 night shifts per month vs. 0~5 night shifts per month: linear regression coefficient, 0.43; SE, 0.10; P < 0.001), self-perceived shortage of physicians in the department (linear regression coefficient, 2.22; SE, 0.08; P < 0.001), and experienced verbal abuse (linear regression coefficient, 1.48; SE, 0.10; P < 0.001) and physical violence (linear regression coefficient, 0.84; SE, 0.08; P < 0.001) in the workplace had higher work-family conflict scores.ConclusionMost emergency department physicians in China experience a high-level work-family conflict. Hospital administrations are recommended to develop family-friendly workplace policies, establish a scientific shift system, and keep the number of emergency department physicians to meet the demand to reduce work-family conflict
- …