Multifunctional Film Assembled from N‑Doped Carbon Nanofiber with Co–N_(4)–O Single Atoms for Highly Efficient Electromagnetic Energy Attenuation

Single-atom materials have demonstrated attractive physicochemical characteristics.However,understanding the relationships between the coordination environment of single atoms and their properties at the atomic level remains a considerable challenge.Herein,a facile waterassisted carbonization approach is developed to fabricate well-defined asymmetrically coordinated Co–N_(4)–O sites on biomass-derived carbon nanofiber(Co–N_(4)–O/NCF)for electromagnetic wave(EMW)absorption.In such nanofiber,one atomically dispersed Co site is coordinated with four N atoms in the graphene basal plane and one oxygen atom in the axial direction.In-depth experimental and theoretical studies reveal that the axial Co–O coordination breaks the charge distribution symmetry in the planar porphyrin-like Co–N_(4) structure,leading to significantly enhanced dielectric polarization loss relevant to the planar Co–N_(4) sites.Importantly,the film based on Co–N_(4)–O/NCF exhibits light weight,flexibility,excellent mechanical properties,great thermal insulating feature,and excellent EMW absorption with a reflection loss of−45.82 dB along with an effective absorption bandwidth of 4.8 GHz.The findings of this work offer insight into the relationships between the single-atom coordination environment and the dielectric performance,and the proposed strategy can be extended toward the engineering of asymmetrically coordinated single atoms for various applications.

Self-Healable and Stretchable PAAc/XG/Bi_(2)Se_(0.3)Te_(2.7) Hybrid Hydrogel Thermoelectric Materials

Thermoelectric power generators have attracted increasing interest in recent years owing to their great potential in wearable electronics power supply.It is noted that thermoelectric power generators are easy to damage in the dynamic service process,resulting in the formation of microcracks and performance degradation.Herein,we prepare a new hybrid hydrogel thermoelectric material PAAc/XG/Bi_(2)Se_(0.3)Te_(2.7)by an in situ polymerization method,which shows a high stretchable and self-healable performance,as well as a good thermoelectric performance.For the sample with Bi_(2)Se_(0.3)Te_(2.7)content of 1.5 wt%(i.e.,PAAc/XG/Bi2Se0.3Te27(1.5 wt%)),which has a room temperature Seebeck coefficient of-0.45 mV K^(-1),and exhibits an open-circuit voltage of-17.91 mV and output power of 38.1 nW at a temperature difference of 40 K.After being completely cut off,the hybrid thermoelectric hydrogel automatically recovers its electrical characteristics within a response time of 2.0 s,and the healed hydrogel remains more than 99%of its initial power output.Such stretchable and self-healable hybrid hydrogel thermoelectric materials show promising potential for application in dynamic service conditions,such as wearable electronics.

Offspring of rats with cerebral hypoxia-ischemia manifest cognitive dysfunction in learning and memory abilities

Neonatal hypoxic-ischemic encephalopathy is a serious neurological disease,often resulting in long-term neurodevelopmental disorders among surviving children.However,whether these neurodevelopmental issues can be passed to offspring remains unclear.The right common carotid artery of 7-day-old parental-generation rats was subjected to permanent ligation using a vessel electrocoagulator.Neonatal hypoxic-ischemic rat models were established by subjecting the rats to 8%O2–92%N2 for 2 hours.The results showed that 24 hours after hypoxia and ischemia,pathological damage,cerebral atrophy,liquefaction,and impairment were found,and Zea-Longa scores were significantly increased.The parental-generation rats were propagated at 3 months old,and offspring were obtained.No changes in the overall brain structures of these offspring rats were identified by magnetic resonance imaging.However,the escape latency was longer and the number of platform crossings was reduced among these offspring compared with normal rats.These results indicated that the offspring of hypoxic-ischemic encephalopathy model rats displayed cognitive impairments in learning and memory.This study was approved by the Animal Care&Welfare Committee of Kunming Medical University,China in 2018(approval No.kmmu2019072).

Comparison of stratospheric evolution during the major sudden stratospheric warming events in 2018 and 2019

Using Modern-Era Retrospective analysis for Research and Applications,Version 2(MERRA-2)data in the northern hemisphere at the 10 hPa level,we compared the stratospheric evolution of temperature and geopotential height during two major sudden stratosphere warming events(SSWs)that occurred in the Arctic winter of 2018 and 2019.In the prewarming period,poleward temperature-enhanced regions were mainly located around 120°E with a displaced vortex and around 120°E and 60°W with splitting vortices.The evolution of geopotential height indicated that these temperature-enhanced regions were both on the western side of high-latitude anticyclones.In the postwarming period,the polar vortex turned from splitting to displacement in the 2018 SSW but from displacement to splitting in the 2019 SSW.Both transitions were observed over the Atlantic region,which may have been caused by anticyclones moving through the polar region.Our findings revealed that the evolution of the anticyclone is important during SSWs and is closely related to temperature-enhanced regions in the prewarming periods and to transitions of the polar vortices in postwarming periods.

Simultaneous Optimization of Power Factor and Thermal Conductivity towards High-Performance InSb-Based Thermoelectric Materials

Thermoelectric performance of InSb is restricted by its low Seebeck coefficient and high thermal conductivity.Here,CuCl is employed to optimize simultaneously the electrical and thermal transport properties of InSb.The substitution of Cl for Sb results in enhanced electron effective mass,leading to high Seebeck coefficient of-159.9 μV/K and high power factor of 31.5 μW·cm^(-1)·K^(-2) at 733 K for InSb+5 wt% CuCl sample.In addition,CuCl doping creates hierarchical architectures composed of CugIn4,Sb,Cu2Sb in InSb,leading to a strengthened phonon scattering in a wide wavelength(i.e.,nano to meso scale),thus a low lattice thermal conductivity of 2.97 W·m^(-1)· K^(-1) at 733 K in InSb+5 wt% CuCl.As a result,a maximum ZT of 0.77 at 733 K has been achieved for the InSb+5 wt% CuCl sample,increasing by ~250% compared to pristine InSb.

Image Classification with Superpixels and Feature Fusion Method

This paper presents an effective image classification algorithm based on superpixels and feature fusion.Differing from classical image classification algorithms that extract feature descriptors directly from the original image,the proposed method first segments the input image into superpixels and,then,several different types of features are calculated according to these superpixels.To increase classification accuracy,the dimensions of these features are reduced using the principal component analysis(PCA)algorithm followed by a weighted serial feature fusion strategy.After constructing a coding dictionary using the nonnegative matrix factorization(NMF)algorithm,the input image is recognized by a support vector machine(SVM)model.The effectiveness of the proposed method was tested on the public Scene-15,Caltech-101,and Caltech-256 datasets,and the experimental results demonstrate that the proposed method can effectively improve image classification accuracy.

Antimicrobial Susceptibility and Sub-MIC Biofilm Formation of <i>Moraxella catarrhalis</i>Clinical Isolates under Anaerobic Conditions

A medium was developed to support the anaerobic growth and antimicrobial susceptibility testing of clinical Moraxella catarrhalis isolates. The MICs of clinical Moraxella catarrhalis isolates under anaerobic conditions were, in general, decreased as compared to atmospheric or capnophilic conditions, while the MBCs for all conditions were within a 2 fold concentration dilution. Biofilm formation was affected by the presence of sub-MIC concentrations of azithromycin and the tested quinolones with the exception of levofloxacin.

An Assessment for Energy Management in Retail Stores

Retail stores are responsible for large energy consumption, which requires more intensified action to improve energy efficiency. Effective energy management can improve energy efficiency in retail stores. However, it is a challenge to implement energy management in retail stores due to different stakeholders’ roles and diverse store features. Literally, technical and management aspects of energy management have received much attention in research. However, limited studies systemically investigate internal and external factors and stakeholders’ involvement in the energy management of retail buildings. With multi-cases in the Philippines, this paper examines the energy profiles in retail stores and develops an assessment for energy management in retail stores. The assessment includes store features, internal and external stakeholders, climate, electricity price and grid condition, energy consumption, and management. The assessment can assist retail stores to develop their energy management plans with their store profile.

Large‑scale transcriptomic and genomic analyses reveal a novel functional gene SERPINB6 for chicken carcass traits

Background Carcass traits are crucial indicators of meat production efficiency.However,the molecular regulatory mechanisms associated with these traits remain unclear.Results In this study,we conducted comprehensive transcriptomic and genomic analyses on 399 Tiannong partridge chickens to identify key genes and variants associated with carcass traits and to elucidate the underlying regulatory mechanisms.Based on association analyses with the elastic net(EN)model,we identified 12 candidate genes(AMY1A,AP3B2,CEBPG,EEF2,EIF4EBP1,FGFR1,FOXD3,GOLM1,LOC107052698,PABPC1,SERPINB6 and TBC1D16)for 4 carcass-related traits,namely live weight,dressed weight,eviscerated weight,and breast muscle weight.SERPINB6 was identified as the only overlapping gene by 3 analyses,EN model analysis,weighted gene co-expression network analysis and differential expression analysis.Cell-level experiments confirmed that SERPINB6 promotes the proliferation of chicken DF1 cells and primary myoblasts.Further expression genome-wide association study and association analysis indicated that rs317934171 is the critical site that enhances SERPINB6 expression.Furthermore,a dual-luciferase reporter assay proved that gga-miR-1615 targets the 3′UTR of SERPINB6.Conclusions Collectively,our findings reveal that SERPINB6 serves as a novel gene for chicken carcass traits by promoting fibroblast and myoblast proliferation.Additionally,the downstream variant rs317934171 regulates SERPINB6 expression.These results identify a new target gene and molecular marker for the molecular mechanisms of chicken carcass traits.

Long-term variation of Arctic Sudden Stratospheric Warmings(SSW)and potential causes

Utilizing the European Centre for Medium-Range Weather Forecast(ECMWF)Reanalysis v5(ERA5),for the first time,we have confirmed close links among Sudden Stratospheric Warmings(SSWs)in the Northern Hemisphere(NH),the polar vortices,and stratospheric Planetary Waves(PWs)by analyzing and comparing their trends.Interestingly,within overall increasing trends,the duration and strength of SSWs exhibit increasing and decreasing trends before and after the winter of 2002,respectively.To reveal possible physical mechanisms driving these trends,we analyzed the long-term trends of the winter(from December to February)polar vortices and of stratospheric PWs with zonal wave number 1.Notably,our results show that in all three time periods(the entire period of 41winters,1980 to 2020,and the two subperiods—1980-2002 and 2002-2020)enhancing SSWs were always accompanied by weakening winter polar vortices and strengthening polar PWs like Stationary Planetary Waves(SPWs)and 16-day waves,and vice versa.This is the first proof,based on ERA5 long-term trend data,that weakening polar vortices and enhancing stratospheric PWs(especially SPWs)could cause an increase in SSWs.

关节镜下内固定关节融合术对晚期踝关节炎患者的疗效及AOFAS和VAS评分的影响

目的探讨关节镜下内固定关节融合术对晚期踝关节炎患者的疗效及美国矫形足踝协会评分系统(AOFAS)和疼痛视觉模拟评分(VAS)的影响。方法选取该院2012年1月-2015年1月收治的晚期踝关节炎患者84例,采用前瞻性研究的方法将研究对象随机分为实验组(42例)及对照组(42例),对照组患者采用传统开放性踝关节融合术,实验组在关节镜辅助下行内固定关节融合术。比较患者手术时间、术中出血量、术后住院时间和并发症发生率,同时随访12~36个月,采用AOFAS评分系统评估疗效,采用VAS评估患者踝关节疼痛程度。结果实验组的手术时间、术中出血量明显少于对照组(P<0.05);两组患者术后情况对比,实验组术后住院时间及关节融合时间均少于对照组(P<0.05);随访1年结果显示:实验组VAS及AOFAS评分均优于对照组(P<0.05),实验组并发症发生率(9.52%)明显低于对照组(28.57%)(P<0.05)。结论关节镜下内固定关节融合术手术时间短、术中出血量少、并发症发生率低,术后愈合率高,远期随访疗效确切,适合在临床推广使用。

依达拉奉对急性脑梗死的疗效及其对出血性转化的影响

目的探究依达拉奉联合阿替普酶治疗急性脑梗死的疗效及其对出血性转化(HT)、五聚素3(PTX3)与血浆脂蛋白相关磷脂酶A2(Lp-PLA2)的影响。方法选取2014年1月—2017年1月承德医学院附属医院收治的116例急性脑梗死患者。根据随机数字表法分为观察组和对照组,每组58例。对照组给予阿替普酶治疗,观察组在对照组基础上给予依达拉奉治疗。比较两组患者的临床疗效、HT的发生率及治疗前后NIHSS评分、ADL评分,同时监测治疗前后血清PTX-3、Lp-PLA2水平及治疗过程中不良反应发生率。结果治疗后两组NIHHS评分均较治疗前降低(P<0.05),且观察组低于对照组(P<0.05);对照组、观察组总有效率分别为50.00%和74.14%,观察组高于对照组(P<0.05);对照组、观察组出血性转化发生率分别为24.14%和10.34%,观察组低于对照组(P <0.05);治疗后两组PTX-3、Lp-PLA2均较治疗前下降(P <0.05),且观察组低于对照组(P <0.05);观察组和对照组不良反应总发生率为10.34%和12.07%,差异无统计学意义(P>0.05)。结论依达拉奉联合阿替普酶治疗急性脑梗死,可以有效改善神经功能缺损,提高临床疗效,预防出血性转化,降低血清Lp-PLA2、PTX3水平,减轻炎症反应,且安全性较好。

冻融法构建超疏水纤维素/壳聚糖气凝胶及其吸油性能

以微晶纤维素、壳聚糖为双网络单元,以氢氧化钠/尿素/水为溶剂体系、甲基三甲氧基硅烷(MTMS)为改性剂,采用“冻融-浸渍”两步法制得超疏水纤维素/壳聚糖复合气凝胶。研究结果表明,该复合气凝胶呈现三维互穿多孔结构,其接触角随着MTMS的加入,先逐渐增大后急剧减小,当MTMS的浓度为1.96 g/μL时,疏水效果最好,接触角可达到151°。此外,该气凝胶具有良好的油/水选择性吸收能力,吸油量最高达到9.3 g/g,且经过5次再生循环后,对于异丙醇的吸附量仍能保持初始值的92.8%,是一种良性可再生的生物质基吸油材料。

影响电池性能的因素:金属离子溶剂化结构衍生的界面行为还是固体电解质界面膜?

通过电解液分解在电极上形成的固体电解质界面(SEI)层被认为是影响电池性能的最重要因素。然而,我们发现金属离子溶剂化结构也会影响其电极性能,尤其可以阐明许多SEI无法解释的实验现象。基于该综述,本文总结了金属离子溶剂化结构和衍生的金属离子去溶剂化行为的重要性,并建立了相应的界面模型以展示界面行为和电极性能之间的关系,并将其应用于不同的电极和电池体系。我们强调了电极界面离子/分子相互作用对电极性能的影响,该解释与以往基于SEI的解释不同。该综述为理解电池性能和指导电解液设计提供了一个新的视角。

Scientific progress regarding neural regeneration in the Web of Science A 10-year bibliometric analysis

BACKGROUND： Neural regeneration following nerve injury is an emerging field that attracts ex- tending interests all over the world. OBJECTIVE： To use bibliometric indexes to track studies focusing on neural regeneration, and to investigate the relationships among geographic origin, countries and institutes, keywords in the published articles, and especially focus on the region distribution, institution distribution, as well as collaborations in Chinese papers indexed in the Web of Science. METHODS： A list of neural regeneration studies was generated by searching the database of the Web of Science-Expanded using the term ＂Neural Regenera＊＂. Inclusive criteria： （1） articles in the field of neural regeneration; （2） fundamental research on animals, clinical trials and case reports; （3） article types： article, review, proceedings paper, note, letter, editorial material, discussion, book chapter; （4） year of publication： 2003-2012; and （5） citation database： Science Citation Index-Expanded. Exclusive criteria： （1） articles requiring manual searching or with access only by telephone; （2） unpublished articles; and （3） corrections. RESULTS： A total of 4 893 papers were retrieved from the Web of Science published between 2003 and 2012. The papers covered 65 countries or regions, of which the United States ranked first with 1 691 papers. The most relevant papers were in the neurosciences and cell biology, and the key- word ＂stem cell＂ was the most frequent. In recent years, China showed a great increase in the number of papers. Over the entire 10 years, there were 922 Chinese papers, with Jilin University ranking first with 58 articles. Chinese papers were published in connection with many countries, in- cluding the United States, Japan, and the United Kingdom. Among the connections, the papers published by the Chinese and the American are 107, with the highest rate. With regard to funding, 689 articles were funded from various projects, occupying 74.72% of the total amount. In these projects, National Foundation and Science and Technology programs were the majority. CONCLUSION： Our bibliometric analysis provides a historical perspective on the progress of neural regeneration research. At present, the number of articles addressing neural regeneration is increasing rapidly; however, through analysis of citations it is clear that there is a long way to go to improve the academic quality.

Ionic liquid/tetraglyme hybrid Mg[TFSI]_2 electrolytes for rechargeable Mg batteries

The electrochemical reversibility of Mg in hybrid electrolytes based on mixtures of ionic liquid and glyme based organic solvents was investigated for applications in rechargeable magnesium batteries(RMBs). The electrolytes demonstrate reversible reduction and oxidation of Mg only after being pre-treated with the dehydrating agent, magnesium borohydride, Mg[BH_4]_2, highlighting the importance of removing water in Mg based electrolytes. The addition magnesium di[bis(trifluoromethanesulfonyl)imide](Mg[TFSI]_2)(0.3 M) to N-butyl-n-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide [C4 mpyr][TFSI]/tetraglyme at a mole ratio of 1:2 showed stable CV cycling over almost 300 cycles while scanning electron microscopy(SEM) and X-ray diffraction(XRD) confirmed Mg deposition, showing non-dendritic morphology and a well-aligned growth. Further thermogravimetric analysis(TGA) demonstrated a mass retention of 79% at 250℃ for this electrolyte suggesting that the presence of the ionic liquid increases thermal stability substantially making these hybrid electrolytes compatible for RMBs.

Role of bimodal-grained structure with random texture on mechanical and corrosion properties of a Mg-Zn-Nd alloy

Fine grained ZN20 alloy was obtained by combining equal-channel angular pressing(ECAP)with extrusion.Microstructural observation showed an obvious grain refinement with an average grain size of 10μm after ECAP.The original bimodal-grained structure composed of coarse grains with strong basal texture and fine grains with random texture was substituted by a new kind of bimodal-grained structure with finer grains and more random texture after 4 passes ECAP at 300℃.The combination of grain refinement and texture weakening caused the ductility can be increased by 40%compared with the as-extruded alloy.Immersion test in simulated intestinal fluid revealed an improvement of corrosion resistance after ECAP.Grain refinement can stable the corrosion product layer and basal texture is more beneficial for the corrosion resistance than the non-basal texture.

Characteristics of the quasi-16-day wave in the mesosphere and lower thermosphere region as revealed by meteor radar,Aura satellite,and MERRA2 reanalysis data from 2008 to 2017

This study presents an analysis of the quasi-16-day wave(Q16DW)at three stations in the middle latitudes by using a meteor radar chain in conjunction with Aura Microwave Limb Sounder temperature data and MERRA2(Modern-Era Retrospective Analysis for Research and Applications,Version 2)reanalysis data from 2008 to 2017.The radar chain consists of three meteor radar stations located at Mohe(MH,53.5°N,122.3°E),Beijing(BJ,40.3°N,116.2°E),and Wuhan(WH,30.5°N,114.6°E).The Q16DW wave exhibits similar seasonal variation in the neutral wind and temperature,and the Q16DW amplitude is generally strong during winter and weak around summer.The Q16DW at BJ was found to have secondary enhancement around September in the zonal wind,which is rarely reported at similar latitudes.The latitudinal variations of the Q16DW in the neutral wind and temperature are quite different.The Q16DW at BJ is the most prominent in both neutral wind components among the three stations and the Q16DW amplitudes at MH and WH are comparable,whereas the wave amplitude in temperature decreases with decreasing latitude.The quasi-geostrophic refractive index squared at the three stations in the period from 2008 to 2017 was revealed.The results indicate that the Q16DW in the mesosphere and lower thermosphere(MLT)at MH has a limited contribution from the lower atmosphere.Around March and October,the Q16DW in the troposphere at BJ can propagate upward into the MLT region,whereas at WH,the contribution to the Q16DW in the MLT region is largely from the mesosphere.

The association between socioeconomic status and visual disability among older adults in China

AIM: To investigate the association between socioeconomic status(SES) and visual disability(VD) among older Chinese adults. METHODS: We obtained data from the Second National Sample Survey on Disability, conducted in China in 2006. A total number of 192 375 older adults(aged≥65 y) were screened for suspected VD via interviews with trained examiners. Those who screened positively for VD were referred to ophthalmologists to obtain a final diagnosis. RESULTS: VD was prevalent among 7.29% of Chinese adults aged 65 and older, and was higher in rural areas(8.71%) than in urban areas(4.82%). After adjusting for SES indicators and covariates, we found that lesseducated older adults were more likely to suffer from VD, with an odds ratio(OR) of 2.50(95%CI: 2.26-2.82) for illiterates, compared with those who graduated from senior high school or above. Older adults who were in the lowest income quintile were more at risk of VD, with an OR of 1.81(95%CI: 1.68-2.95), compared with adults in the highest income quintile. In urban areas, when compared with adults who graduated from senior high school or above, those who did not continue their education after junior high school, primary school, or those who were illiterate, were more likely to suffer from VD, with an OR of 1.35(95%CI: 1.51-1.59), 1.84(95%CI: 1.60-2.12), and 2.63(95%CI: 2.27-3.04), respectively. Lower levels of income were statistically significant when associated with VD. In rural areas, adults who were illiterate had an OR of 2.21(95%CI:1.75-2.79) when compared to adults with senior high school or above education level. Per capita, household income remained significantly associated with VD. Older adults who were ≥85, female, single, and residing in rural areas were associated with higher risks of VD. CONCLUSION: Individual-level SES among the elderly, in the form of education and income, is associated with VD among elderly Chinese adults in both urban and rural areas; however, the association is stronger in rural areas. Further studies are still required to explore the mechanism behind the relationships.

Bimetallic Pt–Ru covalently bonded on carbon nanotubes for efficient methanol oxidation

Platinum-based nanocomposites have been considered as one of the most promising catalysts for methanol oxidation reactions(MORs), which yet still suffer from low electrochemical activity and electron-transfer properties. Apart from van-der-Waals heterostructures,herein, we report a novel nanocomposite with the structure of Pt–Ru bimetallic nanoparticles covalently-bonded onto multi-walled carbon nanotubes (MWCNTs)(Pt–Ru@MWCNT), which have been successfully fabricated via a facile and green synthesis method. It is demonstrated that the Pt–Ru@MWCNT nanocomposite possesses much enhanced electrocatalytic activity with the electrochemical active surface area(ECSA) of 110.4 m^(2)·g^(-1)for Pt towards MOR, which is 2.67 and 4.0 times higher than those of 20wt%commercial Pt@C and Pt-based nanocomposite prepared by other method, due to the improved electron-transfer properties originated from M–O–C covalent bonds. This work provides us a new strategy for the structural design of highly-efficient electrocatalysts in boosting MOR performance.