Polyethylene glycol fusion repair of severed rat sciatic nerves reestablishes axonal continuity and reorganizes sensory terminal fields in the spinal cord

Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions;behavioral recovery is typically poor.We used a plasmalemmal fusogen,polyethylene glycol(PEG),to immediately fuse closely apposed open ends of severed proximal and distal axons in rat sciatic nerves.We have previously reported that sciatic nerve axons repaired by PEG-fusion do not undergo Wallerian degeneration,and PEG-fused animals exhibit rapid(within 2–6 weeks)and extensive locomotor recovery.Furthermore,our previous report showed that PEG-fusion of severed sciatic motor axons was non-specific,i.e.,spinal motoneurons in PEG-fused animals were found to project to appropriate as well as inappropriate target muscles.In this study,we examined the consequences of PEG-fusion for sensory axons of the sciatic nerve.Young adult male and female rats(Sprague–Dawley)received either a unilateral single cut or ablation injury to the sciatic nerve and subsequent repair with or without(Negative Control)the application of PEG.Compound action potentials recorded immediately after PEG-fusion repair confirmed conduction across the injury site.The success of PEG-fusion was confirmed through Sciatic Functional Index testing with PEG-fused animals showing improvement in locomotor function beginning at 35 days postoperatively.At 2–42 days postoperatively,we anterogradely labeled sensory afferents from the dorsal aspect of the hindpaw following bilateral intradermal injection of wheat germ agglutinin conjugated horseradish peroxidase.PEG-fusion repair reestablished axonal continuity.Compared to unoperated animals,labeled sensory afferents ipsilateral to the injury in PEG-fused animals were found in the appropriate area of the dorsal horn,as well as inappropriate mediolateral and rostrocaudal areas.Unexpectedly,despite having intact peripheral nerves,similar reorganizations of labeled sensory afferents were also observed contralateral to the injury and repair.This central reorganization may contribute to the improved behavioral recovery seen after PEG-fusion repair,supporting the use of this novel repair methodology over currently available treatments.

Discovery of tuff in Wujiaping Formation of Upper Permian in the northern Sichuan Basin:Implications for the termination of Emeishan Large Igneous Province

1.Objective The Emeishan basalts is located in southwest China and northern Vietnam,covering an area of 2.5×10^(5) km^(2)(Zhong YT et al.,2014),which is the first widely recognized large igneous province(LIP)in China(Zhang ZS,2009).The Emeishan LIP has attracted a numbers of scholars for the reason that the LIP may play a significant role in the evolution of environment and climate.Yang JH et al.,(2018)pointed out that the weathering of the Emeishan basalts consumed carbon dioxide and caused a decrease in the climate of the early Wuchiapingian.However,the duration and termination of the Emeishan basalts eruption remain in doubt.This paper reports a new discovery of tuffaceous in the middle part of the Upper Permian Wujiaping Formation from the northern margin of the Sichuan Basin,applying of LA-ICP-MS to obtain zircon U-Pb ages of tuffaceous and to constrain the lasted eruption timing of Emeishan LIP.

Awareness of the Termination of Pregnancy Act of the Laws of Zambia among Women of Reproductive Age at Kanyama First Level Hospital in Lusaka District Zambia

Background: Termination of pregnancy (TOP) in Zambia is guided by the Termination of Pregnancy (TOP) Act of 1972 and as amended in 1994 of the laws of Zambia. However, despite provision of Comprehensive abortion care services with the liberal law, statistics at Kanyama First Level Hospital in relation to unsafe illegal abortions are alarming. This study sought to understand the Awareness on the TOP Act of the laws of Zambia among women of reproductive age 15 - 49 years at Kanyama First Level Hospital in Lusaka District. Purpose of the Study: To assess awareness on the TOP Act among women of reproductive age at Kanyama First Level Hospital in Lusaka, Zambia. Methodology: A convergent parallel mixed method design was conducted using both survey and in-depth interviews among women of reproductive age at Kanyama First Level Hospital in Lusaka District. The study surveyed 370 randomly sampled women aged 15 to 49 years old while the in-depth interviews included eight women purposively sampled from the survey population. Survey data was analyzed using descriptive and inferential statistics while qualitative data thematic analysis was used. Results: The study found that 37% of the participants were aware of the TOP Act while 63.8% viewed legalization of abortion for any reason as wrong. The study results also showed that widowed women were 8 times more likely to be aware of the TOP Act compared to single women (AOR: 8.262;95% CI: 1.105, 61.778). Women in business were significantly more likely to be aware of the TOP Act compared to those who reported having no occupation. (AOR: 2.61;95% CI: 1.246, 5.499). Limited access to information, the social stigma attached to abortion, health care providers’ attitudes, cultural norms, values and religious beliefs, restrictive legal requirements, and absence of a supportive network were some of the barriers affecting awareness and utilization of available safe abortion care services. Conclusions: The research findings concluded that a significant lack of awareness among women of reproductive age regarding the Termination of Pregnancy (TOP) Act. The majority of respondents held the view that abortion should only be legalized for medical reasons. Furthermore, there was a notable gap in knowledge concerning the penal code’s provisions on abortion.

Cardiovascular complications following medical termination of pregnancy: An updated review

BACKGROUND Around 1 million cases of medical termination of pregnancy(MTP)take place yearly in the United States of America with around 2 percent of this population developing complications.The cardiovascular(CVD)complications occurring post MTP or after stillbirth is not very well described.AIM To help the reader better understand,prepare,and manage these complications by reviewing various cardiac comorbidities seen after MTP.METHODS We performed a literature search in PubMed,Medline,RCA,and google scholar,using the search terms“abortions”or“medical/legal termination of pregnancy”and“cardiac complications”or“cardiovascular complications”.RESULTS The most common complications described in the literature following MTP were infective endocarditis(IE)(n=16),takotsubo cardiomyopathy(TTC)(n=7),arrhythmias(n=5),and sudden coronary artery dissection(SCAD)(n=4).The most common valve involved in IE was the tricuspid valve in 69%(n=10).The most observed causative organism was group B Streptococcus in 81%(n=12).The most common type of TTC was apical type in 57%(n=4).Out of five patients de veloping arrhythmia,bradycardia was the most common and was seen in 60%(3/5)of the patients.All four cases of SCAD-P type presented as acute coronary syndrome 10-14 d post termination of pregnancy with predominant involvement of the right coronary artery.Mortality was only reported following IE in 6.25%.Clinical recovery was reported consistently after optimal medical management following all these complications.CONCLUSION In conclusion,the occurrence of CVD complications following pregnancy termination is infrequently documented in the existing literature.In this review,the most common CVD complication following MTP was noted to be IE and TTC.

具有时滞效应的air2stream河流水温模型及应用研究

高精度河流水温模型对于深入了解水温的时空变化特征和河流生态修复具有重要意义。基于数据驱动的air2stream模型在保证预测精度的同时,避免了计算的复杂性,已成为河流水温模拟常用的模型。由于水的热惯性及水文条件等的影响,河流水温变化往往显著滞后于气温变化,而air2stream原模型并未考虑滞后效应,导致该模型在流量未知情况下实际精度偏低。为解决该问题,采用气温-水温皮尔逊相关系数计算时滞天数,构建具有时滞的air2stream新模型,进一步根据长江中下游地区两个监测站的多年实测数据验证新模型的有效性和稳定性。结果表明:新模型在不引进额外观测数据的条件下具有更高精度且性能更稳定。相比原模型,在两个监测站新模型的均方根误差分别降低约4.29%和5.85%。新模型具有精度高、水文要素需求少的特点,可为长江中下游的水环境影响评价和生态保护提供依据。

基于Aqua卫星AIRS数据的南大洋大气逆温和逆湿特性研究

南大洋大气普遍存在着逆温和逆湿现象,其分布和变化对海-冰-气之间的物质和通量交换具有重要影响。利用Aqua卫星上搭载的大气红外探测器(AIRS)观测数据,提取了南大洋大气的逆温和逆湿特性,并研究了其时空分布与变化特征。此外,以全球无线电探空数据集的探测结果为参考值,分析了AIRS在进行大气逆温和逆湿探测过程中受到云量影响的特征。结果表明,AIRS估计的逆温特性受云量的影响较小,在多云条件下AIRS也可精确地估计逆温特性。利用AIRS最新的第7版(V7)数据产品对2004-2020年南大洋大气逆温和逆湿的频率(强度)进行研究,发现秋冬季比春夏季高(强),在龙尼冰架、罗斯冰架和南极半岛附近的海域的大气出现逆温和逆湿现象较其他区域更频繁,且强度更强。

磁共振AIR-魔毯线圈在胸椎结核扫描中的应用价值

目的探讨联合应用AIR-魔毯线圈磁共振成像(MRI)对胸椎结核扫描图像信噪比(signal to noise ratio,SNR)、对比噪声比(contrast to noise ratio,CNR)和脂肪抑制成像效果的价值。方法选取我院80例经手术病理证实为胸椎结核患者,按1:1随机分为两组,应用常规线圈(脊柱相控阵线圈,头颈联合线圈)、常规线圈联合AIR魔毯线圈对两组患者分别进行扫描。扫描序列包括胸椎矢状位T_(2)WI,T_(1)WI,T_(2)FLEX,进一步测量、比较SNR,CNR及脂肪抑制效果,分析MRI多序列诊断胸腰椎结核的准确率、特异度和灵敏度。结果常规线圈联合AIR-魔毯线圈扫描组,胸椎矢状位图像的SNR、CNR及压脂效果优于常规线圈组。结论联合应用AIR-魔毯线圈的图像SNR、CNR得到提高,脂肪抑制效果稳定良好。

Determination of Work Function for p-and n-Type 4H-SiC Single Crystals via Scanning Kelvin Probe Force Microscopy

Silicon carbide(SiC) is a promising platform for fabricating high-voltage, high-frequency and high-temperature electronic devices such as metal oxide semiconductor field effect transistors in which many junctions or interfaces are involved. The work function(WF) plays an essential role in these devices. However, studies of the effect of conductive type and polar surfaces on the WF of SiC are limited. Here, we report the measurement of WFs of Si-and C-terminated polar surfaces for both p-type and n-type conductive 4H-SiC single crystals by scanning Kelvin probe microscopy(SKPFM). The results show that p-type SiC exhibits a higher WF than n-type SiC.The WF of a C-terminated polar surface is higher than that of a Si-terminated polar surface, which is further confirmed by first-principles calculations. By revealing this long-standing knowledge gap, our work facilitates the fabrication and development of SiC-based electronic devices, which have tremendous potential applications in electric vehicles, photovoltaics, and so on. This work also shows that SKPFM is a good method for identifying polar surfaces of SiC and other polar materials nondestructively, quickly and conveniently.

Acute suppurative terminal cholangitis:Clinical characteristics of a new subtype of acute cholangitis

Background:Acute suppurative terminal cholangitis(ASTC)is rarer than acute obstructive cholangitis and is not well studied.To explore this subtype of acute cholangitis,we described our clinical experience with ASTC.Methods:We performed a retrospective review of patients with ASTC admitted to our center from September 2014 to August 2020.We analyzed their clinical characteristics,including etiology,clinical manifestations,imaging features,treatment and prognosis.Results:A total of 32 ASTC patients were included in the analysis.The majority of the patients had a history of biliary operations,and clinical manifestations were occult and atypical.The positive rate of bacterial culture was 46.9%.All the patients had typical imaging features on computed tomography and magnetic resonance imaging.Treatment with effective antibiotics was provided as soon as diagnosis was established.After treatment,most patients had a good outcome.Elevated levels of total bilirubin,aspartate aminotransferase,procalcitonin and gamma-glutamyltransferase were the characteristics of critically ill patients and were associated with relatively poor prognosis.Conclusions:Our results demonstrated that ASTC should be recognized as a new subtype of acute cholangitis,and that earlier diagnosis and more personalized treatments are needed.

Mastering air combat game with deep reinforcement learning

Reinforcement learning has been applied to air combat problems in recent years,and the idea of curriculum learning is often used for reinforcement learning,but traditional curriculum learning suffers from the problem of plasticity loss in neural networks.Plasticity loss is the difficulty of learning new knowledge after the network has converged.To this end,we propose a motivational curriculum learning distributed proximal policy optimization(MCLDPPO)algorithm,through which trained agents can significantly outperform the predictive game tree and mainstream reinforcement learning methods.The motivational curriculum learning is designed to help the agent gradually improve its combat ability by observing the agent's unsatisfactory performance and providing appropriate rewards as a guide.Furthermore,a complete tactical maneuver is encapsulated based on the existing air combat knowledge,and through the flexible use of these maneuvers,some tactics beyond human knowledge can be realized.In addition,we designed an interruption mechanism for the agent to increase the frequency of decisionmaking when the agent faces an emergency.When the number of threats received by the agent changes,the current action is interrupted in order to reacquire observations and make decisions again.Using the interruption mechanism can significantly improve the performance of the agent.To simulate actual air combat better,we use digital twin technology to simulate real air battles and propose a parallel battlefield mechanism that can run multiple simulation environments simultaneously,effectively improving data throughput.The experimental results demonstrate that the agent can fully utilize the situational information to make reasonable decisions and provide tactical adaptation in the air combat,verifying the effectiveness of the algorithmic framework proposed in this paper.

基于AirTOp的终端区扇区负荷校准方法研究

管制员工作负荷的评估是扇区运行的一个重要论题,它对提高机场终端区容量值,进而增加航班量和经济收益具有重要意义。结合北京终端区的管制员实际工作负荷评估和校准工作,提出了一种基于AirTOp仿真软件的终端区进近扇区负荷校准的新思路和方法。通过对比同等运行环境下的实际管制负荷与仿真输出,校准管制负荷权重设置,获得一个可用于仿真管制员负荷评估的负荷权值汇总表,使用交叉验证方法将校准后的权值作为输入进行面向扇区的计算机仿真。结果显示仿真负荷与实际负荷偏差值小于±2,证明该校准方法可以适用于对复杂终端区扇区负荷的评估。

Optimal impurity distribution model and experimental verification of variation of lateral doping termination

Based on the charge balance principle,an optimal impurity distribution variation of lateral doping termination(OIDVLD)and its ion-injection mask design method are proposed and verified.The comparative simulations and experiments show that OID-VLD can achieve better blocking ability and reliability than the traditional VLD(T-VLD).Vertical double diffusion MOSFET(VDMOS)with OID-VLD achieved breakdown voltage(BV)of 1684 V and passed the 168 hours 100℃-110℃-120℃-125℃high-temperature reverse bias(HTRB)test,while VDMOS with T-VLD obtained BV of 1636 V and failed in the 20 hours 120℃HTRB test.

Recent progress of self-supported air electrodes for flexible Zn-air batteries

Smart wearable devices are regarded to be the next prevailing technology product after smartphones and smart homes,and thus there has recently been rapid development in flexible electronic energy storage devices.Among them,flexible solid-state zinc-air batteries have received widespread attention because of their high energy density,good safety,and stability.Efficient bifunctional oxygen electrocatalysts are the primary consideration in the development of flexible solid-state zinc-air batteries,and self-supported air cathodes are strong candidates because of their advantages including simplified fabrication process,reduced interfacial resistance,accelerated electron transfer,and good flexibility.This review outlines the research progress in the design and construction of nanoarray bifunctional oxygen electrocatalysts.Starting from the configuration and basic principles of zinc-air batteries and the strategies for the design of bifunctional oxygen electrocatalysts,a detailed discussion of self-supported air cathodes on carbon and metal substrates and their uses in flexible zinc-air batteries will follow.Finally,the challenges and opportunities in the development of flexible zinc-air batteries will be discussed.

Quantitative Determination of Density of Ground State Atomic Oxygen from Both TALIF and Emission Spectroscopy in Hot Air Plasma Generated by Microwave Resonant Cavity

Two experimental techniques have been used to quantify the atomic oxygen density in the case of hot air plasma generated by a microwave （MW） resonant cavity. The latter operates at a frequency of 2.45 GHz inside a cell of gas conditioning at a pressure of 600 mbar, an injected air flow of 12 L/min and an input MW power of 1 kW. The first technique is based on the standard two photon absorption laser induced fluorescence （TALIF） using xenon for calibration but applied for the first time in the present post discharge hot air plasma column having a temperature of about 4500 K near the axis of the nozzle. The second diagnostic technique is an actinometry method based on optical emission spectroscopy （OES）. In this case, we compared the spectra intensities of a specific atomic oxygen line （844 nm） and the closest wavelength xenon line （823 nm）. The two lines need to be collected under absolutely the same spectroscopic parameters. The xenon emission is due to the addition of a small proportion of xenon （1% Xe） of this chemically inert gas inside the air while a further small quantity of H2 （2~） is also added in the mixture in order to collect OH（A- X） and NH（A-X） spectra without noise. The latter molecular spectra are required to estimate gas and excitation temperatures. Optical emission spectroscopy measurements, at for instance the position z=12 mm on the axis plasma column that leads to a gas measured temperature equal to 3500 K, an excitation temperature of about 9500 K and an atomic oxygen density 2.09× 1017＋ 0.2×1017 cm-3. This is in very good agreement with the TALIF measurement, which is equal to 2.0×101T cm-3.

A Structural Insight into Gene Transcription Termination

Scientists have long studied gene transcription to better understand gene regulation and expression in living organisms.Transcription is the process by which DNA is copied into RNA,which then produces proteins that perform various functions in the body.Efficient and accurate transcription termination is crucial for controlling gene expression and maintaining genomic integrity.

Novel Radiation-Adjustable Heating Terminal Based on Flat Heat Pipe Combined with Air Source Heat Pump

The electrification of building heating is an effective way to meet the global carbon target. As a clean and sustainable electrified heating technology, air-source heat pumps (ASHPs) are widely used in areas lacking central heating. However, as a major component of space heating, heating terminals might not fit well with ASHP in order to achieve both intermittency and comfort. Therefore, this study proposes a novel radiation-adjustable heating terminal combined with an ASHP to achieve electrification, intermittency, and better thermal comfort. Radiant terminals currently suffer from three major problems: limited maximum heating capacity, inability to freely adapt, and difficulty with combining them with ASHPs. These problems were solved by improving the structural design of the novel terminal (Improvement A–E). Results showed that the maximum heating capacity increased by 23.6% and radiation heat transfer ratio from 10.1% to 30.9% was provided for users with the novel terminal. Further, new flat heat pipe (FHP) design improved stability (compressor oil return), intermittency (refrigerant thermal inertia), and safety (refrigerant leakage risk) by reducing the length of exposed refrigerant pipes. Furthermore, a new phased operation strategy was proposed for the novel terminal, and the adjustability of the terminal was improved. The results can be used as reference information for decarbonizing buildings by electrifying heating terminals.

METHOD FOR IN SITU DETERMINATION OF P_(CO_2) IN SEA-AIR EQUILIBRIUM SYSTEM

The method for determining P CO 2 in the atmosphere and water by using gas chromatography was studied. For determination of P CO 2 in the atmosphere, a sampling method was developed in which the chromatograph was connected to a 6 port valve with a sampling pipe opening to the atmosphere, so gas pressure in the sampling pipe was identical to that of the atmosphere. A semi automatic seawater atmosphere equilibrium system was designed to determine the P CO 2 in seawater. The equilibrium chamber contained in situ seawater and the well equilibrated gas was pushed into the sampling pipe by sample water, so pressure and temperature calibration could be avoided. This method has high accuracy for the determination of P CO 2 in the air and seawater, and was used for in situ determination of P CO 2 in the atmosphere and of the seawater sample in the JGOFS cruise in the East China Sea.

Determination of the Correlation between the Air Temperature Measured <i>in Situ</i>and Remotely Sensed Data from MODIS and SEVIRI in Congo-Brazzaville

This study compared data from the MODerate-resolution Imaging Spectroradiometer (MODIS) onboard NASA’s Terra satellite and the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on EUMETSAT’s Meterosat Second Generation (MSG) satellite with in situ data obtained from ground observation stations in Congo-Brazzaville. Remote sensing instruments can be used to estimate air temperature, which has an important role in monitoring the effects of climate change. Congo-Brazzaville is located in equatorial forest, which is difficult to access, and has a limited number of ground meteorological stations measuring air temperature. This study used MODIS and MSG data for the period 2009-2014 to assess the performance of land surface temperature data from satellites against in situ data from ground-based stations in Congo-Brazzaville using a linear regression model. This work has allowed us to determine which satellite is best adapted for use in Central Africa.

Determinations of Air Tightness of Covered Slurry Storage Tanks Using Tracer Gas Technique

The objective of this investigation was to study whether it is possible to determine the air tightness of covered slurry storage tanks using tracer gas technique by injection of sulphur hexafluoride （SF6） and measurements of the decay in gas concentrations with an infrared spectrophotometer in the air space above the slurry. By measuring the decay in concentration of injected tracer gas at different occasions, the air exchange rate was determined. Three different types of coverings were studied namely; wooden roof, plastic tent and concrete roof.

Determination of Effectiveness of Energy Management System in Buildings

Building Energy Management Systems(BEMS)are computer-based systems that aid in managing,controlling,and monitoring the building technical services and energy consumption by equipment used in the building.The effectiveness of BEMS is dependent upon numerous factors,among which the operational characteristics of the building and the BEMS control parameters also play an essential role.This research develops a user-driven simulation tool where users can input the building parameters and BEMS controls to determine the effectiveness of their BEMS.The simulation tool gives the user the flexibility to understand the potential energy savings by employing specific BEMS control and help in making intelligent decisions.The simulation is developed using Visual Basic Application(VBA)in Microsoft Excel,based on discrete-event Monte Carlo Simulation(MCS).The simulation works by initially calculating the energy required for space cooling and heating based on current building parameters input by the user in the model.Further,during the second simulation,the user selects all the BEMS controls and improved building envelope to determine the energy required for space cooling and heating during that case.The model compares the energy consumption from the first simulation and the second simulation.Then the simulation model will provide the rating of the effectiveness of BEMS on a continuous scale of 1 to 5(1 being poor effectiveness and 5 being excellent effectiveness of BEMS).This work is intended to facilitate building owner/energy managers to analyze the building energy performance concerning the efficacy of their energy management system.