571 research outputs found

    A hybrid Si@FeSiy/SiOx anode structure for high performance lithium-ion batteries via ammonia-assisted one-pot synthesis

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    Synthesised via planetary ball-milling of Si and Fe powders in an ammonia (NH3) environment, a hybrid Si@FeSiy/SiOx structure shows exceptional electrochemical properties for lithium-ion battery anodes, exhibiting a high initial capacity of 1150 mA h g−1 and a retention capacity of 880 mA h g−1 after 150 cycles at 100 mA g−1; and a capacity of 560 mA h g−1 at 4000 mA g−1. These are considerably high for carbon-free micro-/submicro-Si-based anodes. NH3 gradually turns into N2 and H2 during the synthesis, which facilitates the formation of highly conductive FeSiy (y = 1, 2) phases, whereas such phases were not formed in an Ar atmosphere. Milling for 20–40 h leads to partial decomposition of NH3 in the atmosphere, and a hybrid structure of a Si core of mixed nanocrystalline and amorphous Si domains, shelled by a relatively thick SiOx layer with embedded FeSi nanocrystallites. Milling for 60–100 h results in full decomposition of NH3 and a hybrid structure of a much-refined Si-rich core surrounded by a mantle of a relatively low level of SiOx and a higher level of FeSi2. The formation mechanisms of the SiOx and FeSiy phases are explored. The latter structure offers an optimum combination of the high capacity of a nanostructural Si core, relatively high electric conductivity of the FeSiy phase and high structural stability of a SiOx shell accommodating the volume change for high performance electrodes. The synthesis method is new and indispensable for the large-scale production of high-performance Si-based anode materials

    Antiaging Effect of Pine Pollen in Human Diploid Fibroblasts and in a Mouse Model Induced by D-Galactose

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    The present paper was designed to investigate the effect of pine pollen against aging in human diploid fibroblast 2BS cells and in an accelerated aging model, which was established by subcutaneous injections with D-galactose daily for 8 weeks in C57BL/6J mice. Pine pollen (1 mg/mL and 2 mg/mL) is proved to delay the replicative senescence of 2BS cells as evidenced by enhanced cell proliferation, decreased SA-β-Gal activity, and reversed expression of senescence-associated molecular markers, such as p53, p21Waf1, p16INK4a, PTEN, and p27Kip1 in late PD cells. Besides, pine pollen reversed D-galactose-induced aging effects in neural activity and inflammatory cytokine levels, as indicated by improved memory latency time and reduced error rate in step-down test and decreased concentrations of IL-6 and TNF-α in model mice. Similar to the role of AGEs (advanced glycation endproducts) formation inhibitor aminoguanidine (AG), pine pollen inhibited D-galactose-induced increment of AGEs levels thus reversed the aging phenotypes in model mice. Furthermore, the declined antioxidant activity was obviously reversed upon pine pollen treatment, which may account for its inhibitory effect on nonenzymatic glycation (NEG) in vivo. Our finding presents pine pollen as an attractive agent with potential to retard aging and attenuate age-related diseases in humans

    Complete sequence and organization of Antheraea pernyi nucleopolyhedrovirus, a dr-rich baculovirus

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    <p>Abstract</p> <p>Background</p> <p>The completion and reporting of baculovirus genomes is extremely important as it advances our understanding of gene function and evolution. Due to the large number of viral genomes now sequenced it is very important that authors present significantly detailed analyses to advance the understanding of the viral genomes. However, there is no report of the <it>Antheraea pernyi </it>nucleopolyhedrovirus (AnpeNPV) genome.</p> <p>Results</p> <p>The genome of AnpeNPV, which infects Chinese tussah silkworm (<it>Antheraea pernyi</it>), was sequenced and analyzed. The genome was 126,629 bp in size. The G+C content of the genome, 53.4%, was higher than that of most of the sequenced baculoviruses. 147 open reading frames (ORFs) that putatively encode proteins of 50 or more amino acid residues with minimal overlap were determined. Of the 147 ORFs, 143 appeared to be homologous to other baculovirus genes, and 4 were unique to AnpeNPV. Furthermore, there are still 29 and 33 conserved genes present in all baculoviruses and all lepidopteran baculoviruses respectively. In addition, the total number of genes common to all lepidopteran NPVs is sill 74, however the 74 genes are somewhat different from the 74 genes identified before because of some new sequenced NPVs. Only 6 genes were found exclusively in all lepidopteran NPVs and 12 genes were found exclusively in all Group I NPVs. AnpeNPV encodes <it>v-trex</it>(Anpe115, a 3' to 5' repair exonuclease), which was observed only in CfMNPV and CfDEFNPV in Group I NPVs. This gene potentially originated by horizontal gene transfer from an ancestral host. In addition, AnpeNPV encodes two <it>conotoxin</it>-like gene homologues (<it>ctls</it>), <it>ctl1 </it>and <it>ctl2</it>, which were observed only in HycuNPV, OpMNPV and LdMNPV. Unlike other baculoviruses, only 3 typical homologous regions (<it>hr</it>s) were identified containing 2~9 repeats of a 30 bp-long palindromic core. However, 24 perfect or imperfect direct repeats (<it>dr</it>s) with a high degree of AT content were found within the intergenic spacer regions that may function as non-<it>hr</it>, <it>ori</it>-like regions found in GrleGV, CpGV and AdorGV. 9 <it>dr</it>s were also found in intragenic spacer regions of AnpeNPV.</p> <p>Conclusion</p> <p>AnpeNPV belongs to Group I NPVs and is most similar to HycuNPV, EppoNPV, OpMNPV and CfMNPV based on gene content, genome arrangement, and amino acid identity. In addition, analysis of genes that flank <it>hr</it>s supported the argument that these regions are involved in the transfer of sequences between the virus and host.</p

    Clinicopathological and Prognostic Characteristics in Dedifferentiated/Poorly Differentiated Chordomas: A Pooled Analysis of Individual Patient Data From 58 Studies and Comparison With Conventional Chordomas

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    Background: Currently, the clinicopathological and prognostic characteristics of dedifferentiated chordoma (DC) and poorly differentiated chordoma (PDC) remain poorly understood. In this study, we sought to characterize clinicopathological parameters in a large PDC/DC cohort and determine their correlations with progression-free survival (PFS) and overall survival (OS) of patients. We also attempted to compare clinical features between PDC/DC and conventional chordoma (CC). Methods: Literature searches (from inception to June 01, 2020) using Medline, Embase, Google Scholar and Wanfang databases were conducted to identify eligible studies according to predefined criteria. The local database at our center was also retrospectively reviewed to include CC patients for comparative analysis. Results: Fifty-eight studies from the literature and 90 CC patients from our local institute were identified; in total, 54 PDC patients and 96 DC patients were analyzed. Overall, PDC or DC had distinct characteristics from CC, while PDC and DC shared similar clinical features. Adjuvant radiotherapy and chemotherapy were associated with both PFS and OS in PDC patients in the univariate and/or multivariate analyses. In the DC cohort, tumor resection type, adjuvant chemotherapy and tumor dedifferentiation components significantly affected PFS, whereas none of them were predictive of outcome in the multivariate analysis. By analyzing OS, we found that surgery, resection type and the time to dedifferentiation predicted the survival of DC patients; however, only surgery remained significant after adjusting for other covariables. Conclusions: These data may offer useful information to better understand the clinical characteristics of PDC/DC and may be helpful in improving the outcome prediction of patients

    Aberrant Dynamic Functional Network Connectivity and Graph Properties in Major Depressive Disorder

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    Major depressive disorder (MDD) is a complex mood disorder characterized by persistent and overwhelming depression. Previous studies have identified abnormalities in large scale functional brain networks in MDD, yet most of them were based on static functional connectivity. In contrast, here we explored disrupted topological organization of dynamic functional network connectivity (dFNC) in MDD based on graph theory. One hundred and eighty-two MDD patients and 218 healthy controls were included in this study, all Chinese Han people. By applying group information guided independent component analysis (GIG-ICA) to resting-state functional magnetic resonance imaging (fMRI) data, the dFNCs of each subject were estimated using a sliding window method and k-means clustering. Network properties including global efficiency, local efficiency, node strength and harmonic centrality, were calculated for each subject. Five dynamic functional states were identified, three of which demonstrated significant group differences in their percentage of state occurrence. Interestingly, MDD patients spent much more time in a weakly-connected State 2, which includes regions previously associated with self-focused thinking, a representative feature of depression. In addition, the FNCs in MDD were connected differently in different states, especially among prefrontal, sensorimotor, and cerebellum networks. MDD patients exhibited significantly reduced harmonic centrality primarily involving parietal lobule, lingual gyrus and thalamus. Moreover, three dFNCs with disrupted node properties were commonly identified in different states, and also correlated with depressive symptom severity and cognitive performance. This study is the first attempt to investigate the dynamic functional abnormalities in MDD in a Chinese population using a relatively large sample size, which provides new evidence on aberrant time-varying brain activity and its network disruptions in MDD, which might underscore the impaired cognitive functions in this mental disorder

    Decreased ventricular systolic function in chemotherapy-naive patients with acute myeloid leukemia: a three-dimensional speckle-tracking echocardiography study

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    BackgroundThe relationship between acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL) and cardiac function is not well established. This study aimed to evaluate whether AML patients exist early myocardial damages prior to chemotherapy and to investigate its association with cardiovascular biomarkers.MethodsConventional echocardiography and three-dimensional speckle-tracking strain analysis were performed prospectively in 72 acute leukemia (AL) patients before any chemotherapy therapy (of whom 44 were AML patients, 28 ALL patients). The results were compared with those from 58 control group matched for age and gender.ResultsThere were no significant differences in conventional biventricular systolic function parameters between AL patients and controls. The left ventricular global longitudinal strain (LVGLS) and right ventricular free wall longitudinal strain (RVFWLS) were significantly lower in AL patients (−23.0 ± 1.4% vs. −24.1 ± 1.3% and −27.9 ± 7.1% vs. −33.0 ± 4.6%, respectively, P &lt; 0.001 for all). Compared with ALL patients, AML patients had lower LVGLS and RVFWLS (−22.7 ± 1.3% vs. −23.5 ± 1.6% and −26.2 ± 7.6% vs. −30.4 ± 5.5%, respectively, P &lt; 0.05 for all). LVGLS was lower in ALL patients compared with controls (−23.5 ± 1.6% vs. −24.7 ± 1.4%, P &lt; 0.05), however, there was no difference in right ventricular systolic function parameters between the two groups. LVGLS in AL patients was independently correlated with left ventricular ejection fraction (LVEF) and the absolute number of circulating lymphocytes.ConclusionsOur findings suggest that baseline myocardial systolic function is lower in AL patients than controls. AML patients had lower baseline LVGLS and RVFWLS than controls and ALL patients. The decreased LVGLS is correlated with LVEF and the absolute number of circulating lymphocytes

    The Relationship Between Cognitive Dysfunction and Symptom Dimensions Across Schizophrenia, Bipolar Disorder, and Major Depressive Disorder

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    Background: Cognitive dysfunction is considered a core feature among schizophrenia (SZ), bipolar disorder (BD), and major depressive disorder (MDD). Despite abundant literature comparing cognitive dysfunction among these disorders, the relationship between cognitive dysfunction and symptom dimensions remains unclear. The study aims are a) to identify the factor structure of the BPRS-18 and b) to examine the relationship between symptom domains and cognitive function across SZ, BD, and MDD.Methods: A total of 716 participants [262 with SZ, 104 with BD, 101 with MDD, and 249 healthy controls (HC)] were included in the study. One hundred eighty participants (59 with SZ, 23 with BD, 24 with MDD, and 74 HC) completed the MATRICS Consensus Cognitive Battery (MCCB), and 507 participants (85 with SZ, 89 with BD, 90 with MDD, and 243 HC) completed the Wisconsin Card Sorting Test (WCST). All patients completed the Brief Psychiatric Rating Scale (BPRS).Results: We identified five BPRS exploratory factor analysis (EFA) factors (“affective symptoms,” “psychosis,” “negative/disorganized symptoms,” “activation,” and “noncooperation”) and found cognitive dysfunction in all of the participant groups with psychiatric disorders. Negative/disorganized symptoms were the most strongly associated with cognitive dysfunctions across SZ, BD, and MDD.Conclusions: Our findings suggest that cognitive dysfunction severity relates to the negative/disorganized symptom domain across SZ, BD, and MDD, and negative/disorganized symptoms may be an important target for effective cognitive remediation in SZ, BD, and MDD
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