Synthesis of a Flexible Freestanding Sulfur/Polyacrylonitrile/Graphene Oxide as the Cathode for Lithium/Sulfur Batteries

Rechargeable lithium/sulfur (Li/S) batteries have received quite significant attention over the years because of their high theoretical specific capacity (1672 mAh g1) and energy density (2600 mAh g1) which has led to more efforts for improvement in their electrochemical performance. Herein, the synthesis of a flexible freestanding sulfur/polyacrylonitrile/graphene oxide (S/PAN/GO) as the cathode for Li/S batteries by simple method via vacuum filtration is reported. The S/PAN/GO hybrid binder-free electrode is considered as one of the most promising cathodes for Li/S batteries. Graphene oxide (GO) slice structure provides effective ion conductivity channels and increases structural stability of the ternary system, resulting in excellent electrochemical properties of the freestanding S/PAN/GO cathode. Additionally, graphene oxide (GO) membrane was able to minimize the polysulfides’ dissolution and their shuttle, which was attributed to the electrostatic interactions between the negatively-charged species and the oxygen functional groups on GO. Furthermore, these oxygen-containing functional groups including carboxyl, epoxide and hydroxyl groups provide active sites for coordination with inorganic materials (such as sulfur). It exhibits the initial reversible specific capacity of 1379 mAh g1 at a constant current rate of 0.2 C and maintains 1205 mAh g1 over 100 cycles (~87% retention). In addition, the freestanding S/PAN/GO cathode displays excellent coulombic efficiency (~100%) and rate capability, delivering up to 685 mAh g1 capacity at 2

Polysaccharide Extracted from Laminaria japonica

This study aimed to determine the effect of topically applied Laminaria polysaccharide (LP) on skin aging. We applied ointment containing LP (10, 25, and 50 μg/g) or vitamin E (10 μg/g) to the dorsal skin of aging mice for 12 months and young control mice for 4 weeks. Electron microscopy analysis of skin samples revealed that LP increased dermal thickness and skin collagen content. Tissue inhibitor of metalloprotease- (TIMP-) 1 expression was upregulated while that of matrix metalloproteinase- (MMP-) 1 was downregulated in skin tissue of LP-treated as compared to untreated aging mice. Additionally, phosphorylation of c-Jun N-terminal kinase (JNK) and p38 was higher in aging skin than in young skin, while LP treatment suppressed phospho-JNK expression. LP application also enhanced the expression of antioxidative enzymes in skin tissue, causing a decrease in malondialdehyde levels and increases in superoxide dismutase, catalase, and glutathione peroxidase levels relative to those in untreated aging mice. These results indicate that LP inhibits MMP-1 expression by preventing oxidative stress and JNK phosphorylation, thereby delaying skin collagen breakdown during aging

Identifying Communication Topologies on Twitter

Social networks are known for their decentralization and democracy. Each individual has a chance to participate and influence any discussion. Even with all the freedom, people’s behavior falls under patterns that are observed in numerous situations. In this paper, we propose a methodology that defines and searches for common communication patterns in topical networks on Twitter. We analyze clusters according to four traits: number of nodes the cluster has, their degree and betweenness centrality values, number of node types, and whether the cluster is open or closed. We find that cluster structures can be defined as (a) fixed, meaning that they are repeated across datasets/topics following uniform rules, or (b) variable if they follow an underlying rule regardless of their size. This approach allows us to classify 90% of all conversation clusters, with the number varying by topic. An increase in cluster size often results in difficulties finding topological shape rules; however, these types of clusters tend to exhibit rules regarding their node relationships in the form of centralization. Most individuals do not enter large-scale discussions on Twitter, meaning that the simplicity of communication clusters implies repetition. In general, power laws apply for the influencer connection distribution (degree centrality) even in topical networks

Research on Formation Identification Based on Drilling Shock and Vibration Parameters and Energy Principle

In geotechnical engineering and geological survey, the stratum structure and its corresponding physical and mechanical properties are the most concerned. The stratum structure not only affects the safety of the project but also plays a decisive role in the construction method and construction sequence. In this paper, a new type of stratum geological interface recognition system is adopted, and an R-20 rotary drilling rig is used to conduct on-site drilling experiments for a granite site with no ventilation. The research results show that the system can monitor and record the main parameters (axial pressure, drilling rate, rotation speed, flushing fluid pressure, and torque) of the drilling rig during the drilling process. The comparative analysis of monitoring data and on-site survey results shows that different drilling parameters have different sensitivities to changes in the formation structure. According to the prediction accuracy, the ranking from high to low is drilling rate, axial pressure, torque, rotation speed, and flushing fluid pressure. In drilling engineering, by observing the change law of drilling rig parameters, not only can the position of the special rock mass interlayer be predicted, but also the stratum structure and strength can be identified, and the prediction formula is also given. Based on the established drilling specific energy formula, the energy analysis method is used to predict the formation structure and compressive strength, and the corresponding prediction formula is given. The research results show that, compared with the single drilling parameter prediction method, the rock-soil structure and strength identification method based on energy theory has higher prediction accuracy and can meet engineering needs

Comparison of two functional kappa light‐chain transcripts amplified from a hybridoma

Three heavy‐chain and three kappa (κ)‐chain transcripts were amplified from hybridoma cells secreting a monoclonal antibody (m A b) against transferrin receptor. Sequence analysis via IMGT / V ‐ QUEST yielded the functional/aberrant prediction. Two functional κ‐chain transcripts, V κ2 and V κ3, and one functional V H 1 were revealed. Comprehensive bioinformatics analyses including sequence alignment, phylogenetic tree, somatic hypermutation prediction, and three‐dimensional‐molecular structure modeling were used to predict the origin of the two κ‐chain transcripts. The results of bioinformatics analysis suggest that V κ3 is derived from the myeloma partner of the hybridoma; V κ2 is derived from B‐cell. Functional transcripts V H 1 and V κ2 and V κ3 were then used to construct two chimeric antibodies chi‐ C 2 ( V κ2– V H 1) and chi‐ C 3 ( V κ3–V H 1), respectively. Antigen‐binding experiments showed that only chi‐ C 2 remained the same affinity as its parental mAb. Possible explanations for the coexistence of two functional κ‐chain transcripts and the different affinity of the two chimeric antibodies are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98790/1/bab1080.pd

Synthesis of a Flexible Freestanding Sulfur/Polyacrylonitrile/Graphene Oxide as the Cathode for Lithium/Sulfur Batteries

Rechargeable lithium/sulfur (Li/S) batteries have received quite significant attention over the years because of their high theoretical specific capacity (1672 mAh g1) and energy density (2600 mAh g1) which has led to more efforts for improvement in their electrochemical performance. Herein, the synthesis of a flexible freestanding sulfur/polyacrylonitrile/graphene oxide (S/PAN/GO) as the cathode for Li/S batteries by simple method via vacuum filtration is reported. The S/PAN/GO hybrid binder-free electrode is considered as one of the most promising cathodes for Li/S batteries. Graphene oxide (GO) slice structure provides effective ion conductivity channels and increases structural stability of the ternary system, resulting in excellent electrochemical properties of the freestanding S/PAN/GO cathode. Additionally, graphene oxide (GO) membrane was able to minimize the polysulfides’ dissolution and their shuttle, which was attributed to the electrostatic interactions between the negatively-charged species and the oxygen functional groups on GO. Furthermore, these oxygen-containing functional groups including carboxyl, epoxide and hydroxyl groups provide active sites for coordination with inorganic materials (such as sulfur). It exhibits the initial reversible specific capacity of 1379 mAh g1 at a constant current rate of 0.2 C and maintains 1205 mAh g1 over 100 cycles (~87% retention). In addition, the freestanding S/PAN/GO cathode displays excellent coulombic efficiency (~100%) and rate capability, delivering up to 685 mAh g1 capacity at 2

Abnormal resting state activity of left middle occipital gyrus and its functional connectivity in female patients with major depressive disorder

Abstract Background Women are more susceptible to major depressive disorder (MDD). A possible explanation is that women have a trait tendency to engage in a ruminative response style. Depending on cognitive model of depression, attention bias, memory bias and self-referential bias were closely related among depressed patients. Previous studies have explored the neural mechanism of the cognitive biases by using amplitude of low frequency fluctuations (ALFF) or functional connectivity (FC), and few combined these two metrics, especially focusing on female patients. Methods We assessed 25 female patients diagnosed with MDD and 13 well matched healthy controls (HCs) using Rs-fMRI. Two metrics ALFF and FC based on abnormal ALFF were explored and made comparisons. Results Compared with HCs, female patients with MDD showed that one cluster with significantly decreased ALFF in the left middle occipital gyrus(L-MOG). Furtherly we founded depressed female subjects showed significantly lower FC between the L-MOG seed and left orbitofrontal cortex, and significantly higher FC between the L-MOG seed and left medial prefrontal gyrus and left hippocampus. Conclusions Our results showed L-MOG may act as a connection, which involved in the processing of cognitive biases of MDD by connected with limbic-cortical regions in resting state. These findings may enhance the understanding of the neurobiological mechanism in female patients with MDD