Polysulfide chemistry in metal-sulfur batteries.

Renowned for their high theoretical energy density and cost-effectiveness, metal-sulfur (M-S) batteries are pivotal in overcoming the current energy storage bottlenecks and accelerating the transition toward a cleaner society. Polysulfides (PSs) serve as essential intermediates in M-S batteries and bridge the electrochemical redox processes of sulfur, playing a decisive role in controlling the electrode behaviors and regulating the battery performances. Understanding PS chemistry across diverse battery environments is key to advancing M-S batteries.

Kinetic Evaluation on Lithium Polysulfide in Weakly Solvating Electrolyte toward Practical Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries are highly considered as next-generation energy storage techniques. Weakly solvating electrolyte with low lithium polysulfide (LiPS) solvating power promises Li anode protection and improved cycling stability. However, the cathodic LiPS kinetics is inevitably deteriorated, resulting in severe cathodic polarization and limited energy density.

Anion-Involved Solvation Structure of Lithium Polysulfides in Lithium-Sulfur Batteries.

Lithium polysulfides (LiPSs) are pivotal intermediates involved in all the cathodic reactions in lithium-sulfur (Li-S) batteries. Elucidating the solvation structure of LiPSs is the first step for rational design of electrolyte and improving Li-S battery performances. Herein, we investigate the solvation structure of LiPSs and find that Li salt anions tend to enter the first solvation sheath of LiPSs and form contact ion pairs in electrolyte.

Cathode Kinetics Evaluation in Lean-Electrolyte Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries afford great promise on achieving practical high energy density beyond lithium-ion batteries. Lean-electrolyte conditions constitute the prerequisite for achieving high-energy-density Li-S batteries but inevitably deteriorates battery performances, especially the sulfur cathode kinetics. Herein, the polarizations of the sulfur cathode are systematically decoupled to identify the key kinetic limiting factor in lean-electrolyte Li-S batteries.

Morphological characteristics influence the spatial mixing patterns of shorebirds at Shengjin Lake.

The coexistence of species with similar ecological niches is one of the core interests of community ecology research. However, how functional feeding traits, including bill size and leg length, determine the niche of mixed flocks of shorebird species has seldomly been studied, as well as, microhabitat variables affect the spatial patterns of availability and the quality of patches for wintering. From October 2016 to March 2017 at Shengjin Lake, Anhui Province, China, we recorded 226 scan samples from the different microhabitats and 93 focal animal videos of four common shorebird species: common greenshank, spotted redshank, Kentish plover, and little ringed plover.

Semi-Immobilized Molecular Electrocatalysts for High-Performance Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries constitute promising next-generation energy storage devices due to the ultrahigh theoretical energy density of 2600 Wh kg. However, the multiphase sulfur redox reactions with sophisticated homogeneous and heterogeneous electrochemical processes are sluggish in kinetics, thus requiring targeted and high-efficient electrocatalysts. Herein, a semi-immobilized molecular electrocatalyst is designed to tailor the characters of the sulfur redox reactions in working Li-S batteries.

Understanding the Impedance Response of Lithium Polysulfide Symmetric Cells.

Lithium-sulfur (Li-S) batteries are highly considered for next-generation energy storage due to their ultrahigh theoretical energy density of 2600 Wh kg. The conversion reactions between lithium polysulfides (LiPSs) constitute the core process in working Li-S batteries. Electrochemical impedance spectroscopy (EIS) analysis of LiPS symmetric cells is an effective tool to provide detailed information on the LiPS conversion reactions and direct further kinetic promotion.

Direct Intermediate Regulation Enabled by Sulfur Containers in Working Lithium-Sulfur Batteries.

Polysulfide intermediates (PSs), the liquid-phase species of active materials in lithium-sulfur (Li-S) batteries, connect the electrochemical reactions between insulative solid sulfur and lithium sulfide and are key to full exertion of the high-energy-density Li-S system. Herein, the concept of sulfur container additives is proposed for the direct modification on the PSs species. By reversible storage and release of the sulfur species, the container molecule converts small PSs into large organosulfur species.

Spatial and Kinetic Regulation of Sulfur Electrochemistry on Semi-Immobilized Redox Mediators in Working Batteries.

Use of redox mediators (RMs) is an effective strategy to enhance reaction kinetics of multi-electron sulfur electrochemistry. However, the soluble small-molecule RMs usually aggravate the internal shuttle and thus further reduce the battery efficiency and cyclability. A semi-immobilization strategy is now proposed for RM design to effectively regulate the sulfur electrochemistry while circumvent the inherent shuttle issue in a working battery.

Significant Differences in the Gut Bacterial Communities of Hooded Crane () in Different Seasons at a Stopover Site on the Flyway.

Intestinal bacterial communities form an integral component of the organism. Many factors influence gut bacterial community composition and diversity, including diet, environment and seasonality. During seasonal migration, birds use many habitats and food resources, which may influence their intestinal bacterial community structure.

Microhabitat variables explain patch switching by wintering Bewick's swans through giving-up net energy intake rates.

Microhabitat variables are determinants for animals to select forage patches and evaluate the cost/benefit tradeoffs of habitat switching. Optimal foragers would weigh habitat quality by giving-up net energy intake rate (GUN), which includes the energy intake rate and cost rate. The GUNs, energy intake rate, and cost rate can be influenced by variations in different microhabitat factors and interactive effects.

The Influence of Food Density, Flock Size, and Disturbance on the Functional Response of Bewick's Swans () in Wintering Habitats.

Perceiving how animals adjust their feeding rate under a variety of environmental conditions and understanding the tradeoffs in their foraging strategies are necessary for conservation. The Holling functional response, which describes the relationship of feeding rate and food density to searching rate and handling time, has been applied to a range of waterbirds, especially with regard to Type II functional responses that describe an increasing feeding rate with food density but at a decelerating rate as the curve approaches the asymptote. However, feeding behavior components (feeding rate, searching rate, and handling time) are influenced by factors besides prey density, such as vigilance and flock size.

Complete mitochondrial genome of .

Crested goshawk () is a diurnal raptor tropical Asia which is a bird species in family Accipitridae. In the present study, we determined its complete mitochondrial genome by PCR-based method. The complete mitochondrial genome was 18,454 bp in length which overall base composition was 31.

Implanting Atomic Cobalt within Mesoporous Carbon toward Highly Stable Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries hold great promise to serve as next-generation energy storage devices. However, the practical performances of Li-S batteries are severely limited by the sulfur cathode regarding its low conductivity, huge volume change, and the polysulfide shuttle effect. The first two issues have been well addressed by introducing mesoporous carbon hosts to the sulfur cathode.

Variations in gut bacterial communities of hooded crane () over spatial-temporal scales.

Background: Microbes have been recognized as important symbionts to regulate host life. The animal gut harbors abundance and diverse bacteria. Numerous internal and external factors influence intestinal bacterial communities, including diet, seasonal fluctuations and habitat sites.

From Supramolecular Species to Self-Templated Porous Carbon and Metal-Doped Carbon for Oxygen Reduction Reaction Catalysts.

The preparation of carbon materials usually involves the decomposition of precursors and the reorganization of the as-generated fragments. However, the cleavage of bonds and the simultaneous formation of new bonds at nearly the same positions prevents effective yet precise fabrication. Herein, a supramolecular precursor, cucurbit[6]uril, that contains multiple bonds with distinct bond strengths is proposed to decouple the twin problem of simultaneous bond cleavage and formation, allowing multistage transformations to hierarchical porous carbon and metal-doped carbon in a single yet effective pyrolysis step without the need of a template or additional purification.

Downregulated PITX1 Modulated by MiR-19a-3p Promotes Cell Malignancy and Predicts a Poor Prognosis of Gastric Cancer by Affecting Transcriptionally Activated PDCD5.

Background/aims: PITX1 has been identified as a potential tumor-suppressor gene in several malignant tumors. The molecular mechanism underlying PITX1, particularly its function as a transcription factor regulating gene expression during tumorigenesis, is still poorly understood.

Methods: The expression level and location of PITX1 were determined by quantitative reverse transcription PCR (qRT-PCR) and immunohistochemical staining in gastric cancer (GC).

The gut microbiome of hooded cranes (Grus monacha) wintering at Shengjin Lake, China.

Gut microbes of animals play critical roles in processes such as digestion and immunity. Therefore, identifying gut microbes will shed light on understanding the annual life of animal species, particularly those that are threatened or endangered. In the present study, we conducted nucleotide sequence analyses of the 16S rRNA genes of gut microbiome of the hooded cranes (Grus monacha) wintering at Shengjin Lake, China, by Illumina high-throughput sequencing technology.

Upregulation of DNMT1 mediated by HBx suppresses RASSF1A expression independent of DNA methylation.

The hepatitis B virus (HBV) X protein (HBx) plays a key role in the molecular pathogenesis of HBV-related hepatocellular carcinoma (HCC). However, its critical gene targets remain largely unknown. RASSF1A gene (Ras-association domain family 1A, RASSF1A), a tumor-suppressor gene, is frequently found to be hypermethylated and downregulated in HCC.

DNMT3A rs36012910 A>G polymorphism and gastric cancer susceptibility in a Chinese population.

DNA-methyltransferase (DNMT)-3A plays a crucial role in embryonic development and aberrant DNA methylation in carcinogenesis. Polymorphisms of the DNMT3A gene may influence its enzymatic activity and its contribution to susceptibility to cancer. This study evaluated the association of DNMT3A rs36012910 A>G with susceptibility to gastric cancer (GC) in a Chinese population.

Association of the DNMT3A -448A>G polymorphism with genetic susceptibility to colorectal cancer.

The DNA methyltransferase 3A (DNMT3A) -448A>G polymorphism is a novel functional single nucleotide polymorphism (SNP) that contributes to the genetic susceptibility to gastric cancer. In this study, we aimed to assess the genotype frequencies of DNMT3A -448A>G in colorectal cancer (CRC) patients and healthy control subjects, and to explore the association of the DNMT3A functional SNP, -448A>G, with genetic susceptibility to CRC. Genomic DNA was extracted from samples of 258 patients with CRC and 280 healthy controls.

A functional polymorphism in the DNA methyltransferase-3A promoter modifies the susceptibility in gastric cancer but not in esophageal carcinoma.

Background: DNA-methyltransferase (DNMT)-3A plays an important role in the development of embryogenesis and the generation of aberrant methylation in carcinogenesis. The aim of this study was to investigate the role of a DNMT3A promoter genetic variant on its transcriptional activity and to evaluate the association between DNMT3A gene polymorphism and the susceptibility to gastric cancer (GC) and oesophagus carcinoma (EC) in the Chinese population.

Methods: We selected one of the single nucleotide polymorphisms (SNPs) -448A>G in the DNMT3A promoter region and evaluated its effect on activity using a luciferase assay.