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Multidimensional compound Poisson distributions in free probability
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作者 Guimei An Mingchu Gao 《中国科学:数学英文版》 SCIE CSCD 2019年第5期921-934,共14页
Inspired by Speicher’s multidimensional free central limit theorem and semicircle families, we prove an in?nite dimensional compound Poisson limit theorem in free probability, and de?ne in?nite dimensional compound f... Inspired by Speicher’s multidimensional free central limit theorem and semicircle families, we prove an in?nite dimensional compound Poisson limit theorem in free probability, and de?ne in?nite dimensional compound free Poisson distributions in a non-commutative probability space. In?nite dimensional free in?nitely divisible distributions are de?ned and characterized in terms of their free cumulants. It is proved that for a sequence of random variables, the following three statements are equivalent:(1) the distribution of the sequence is multidimensional free in?nitely divisible;(2) the sequence is the limit in distribution of a sequence of triangular trays of families of random variables;(3) the sequence has the same distribution as that of {a1(i): i = 1, 2,...}of a multidimensional free L′evy process {{a1(i): i = 1, 2,...} : t≥0}. Under certain technical assumptions, this is the case if and only if the sequence is the limit in distribution of a sequence of sequences of random variables having multidimensional compound free Poisson distributions. 展开更多
关键词 free PROBABILITY MULTIDIMENSIONAL free POISSON DISTRIBUTIONS MULTIDIMENSIONAL free INFINITELY divisible DISTRIBUTIONS
利用Free Video to JPG Converter软件探究弹簧振子的运动
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作者 胡瀚玮 张洪明 林耕波 《湖南中学物理》 2019年第4期75-76,共2页
本文利用Free Video to JPG Converter软件能将视频自动截图的功能,结合Excel软件分析数据,再加上合理外推得到弹簧振子的位移时间图像是一条正弦曲线。
关键词 Free VIDEO to JPG Converter软件 弹簧振子 正弦曲线
Effects of hurricane forward speed and approach angle on storm surges:an idealized numerical experiment 预览
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作者 Chenguang Zhang Chunyan Li 《海洋学报:英文版》 SCIE CAS CSCD 2019年第7期48-56,共9页
The effects of hurricane forward speed(V)and approach angle(θ)on storm surge are important and a systematic investigation covering possible and continuous ranges of these parameters has not been done before.Here we p... The effects of hurricane forward speed(V)and approach angle(θ)on storm surge are important and a systematic investigation covering possible and continuous ranges of these parameters has not been done before.Here we present such a study with a numerical experiment using the Finite Volume Community Ocean Model(FVCOM).The hurricane track is simplified as a straight line,such that V andθfully define the motion of the hurricane.The maximum surge is contributed by both free waves and a forced storm surge wave moving with the hurricane.Among the free waves,Kelvin-type waves can only propagate in the down-coast direction.Simulations show that those waves can only have a significant positive storm surge when the hurricane velocity has a down-coast component.The optimal values of V andθthat maximize the storm surge in an idealized semi-circular ocean basin are functions of the bathymetry.For a constant bathymetry,the maximum surge occurs when the hurricane approaches the coast from the normal direction when the free wave generation is minimal;for a stepped bathymetry,the maximum surge occurs at a certain acute approach angle which maximizes the duration of persistent wind forcing;a step-like bathymetry with a sloped shelf is similar to the stepped bathymetry,with the added possibility of landfall resonance when the free and forced waves are moving at about the same velocity.For other cases,the storm surge is smaller,given other parameters(hurricane size,maximum wind speed,etc.)unchanged. 展开更多
关键词 storm SURGE experiments FVCOM HURRICANE forward speed APPROACH ANGLE KELVIN waves forced and free SURGE interactions
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Unsteady Liquid Film Flow with a Prescribed Free-Surface Velocity
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作者 方铁钢 王甫军 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第1期36-39,共4页
A liquid film flow over a flat plate is investigated by prescribing the unsteady interface velocity.With this prescribed surface velocity,the governing Navier-Stokes (NS)equations are transformed into a similarity ord... A liquid film flow over a flat plate is investigated by prescribing the unsteady interface velocity.With this prescribed surface velocity,the governing Navier-Stokes (NS)equations are transformed into a similarity ordinary differential equation,which is solved numerically.The flow characteristics is controlled by an unsteadiness parameter S and the flow direction parameter Λ.The results show that solutions only exist for a certain range of the unsteadiness parameter,i.e.,S≤1 for Λ=-1 and S≤-2.815877 for Λ=1.In the solution domain, the dimensionless liquid film thickness β decreases with S for both the cases.The wall shear stress increases with the decrease of S for Λ=-1.However,for Λ=-1 the shear stress magnitude first decreases and then increases with the decrease of S.There are no zero erossing points for the velocity profiles for both the cases.The profiles of velocity stay either positive or negative all the time,except for the wall zero velocity.Consequently, the vertical velocity becomes a monotonic function.To maintain the prescribed velocity,mass transpiration is generally needed,but for the shrinking film case it is possible to have an impermeable wall.The results are also an exact solution to the furl NS equations. 展开更多
关键词 Free surface VELOCITY UNSTEADY liquid FILM The governing EQUATION
Planar Cubic G1 Hermite Interpolant with Minimal Quadratic Oscillation in Average 预览
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作者 Li Jun-cheng 《数学研究通讯:英文版》 CSCD 2019年第3期219-224,共6页
In this paper we apply a new method to choose suitable free parameters of the planar cubic G1 Hermite interpolant. The method provides the cubic G1 Hermite interpolant with minimal quadratic oscillation in average. We... In this paper we apply a new method to choose suitable free parameters of the planar cubic G1 Hermite interpolant. The method provides the cubic G1 Hermite interpolant with minimal quadratic oscillation in average. We can use the method to construct the optimal shape-preserving interpolant. Some numerical examples are presented to illustrate the effectiveness of the method. 展开更多
关键词 CUBIC HERMITE interpolant free parameter optimization shape-preserving interpolant
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Development of readout electronics for bunch arrival-time monitor system at SXFEL 预览
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作者 Jin-Guo Wang Bo Liu 《核技术:英文版》 SCIE CAS CSCD 2019年第5期113-121,共9页
A bunch arrival-time monitor (BAM) system, based on electro-optical intensity modulation scheme, is under study at Shanghai Soft X-ray Free Electron Laser. The aim of the study is to achieve high-precision time measur... A bunch arrival-time monitor (BAM) system, based on electro-optical intensity modulation scheme, is under study at Shanghai Soft X-ray Free Electron Laser. The aim of the study is to achieve high-precision time measurement for minimizing bunch fluctuations. A readout electronics is developed to fulfill the requirements of the BAM system. The readout electronics is mainly composed of a signal conditioning circuit, field-programmable gate array (FPGA), mezzanine card (FMC150), and powerful FPGA carrier board. The signal conditioning circuit converts the laser pulses into electrical pulse signals using a photodiode. Thereafter, it performs splitting and low-noise amplification to achieve the best voltage sampling performance of the dual-channel analog-to-digital converter (ADC) in FMC150. The FMC150 ADC daughter card includes a 14-bit 250 Msps dual-channel high-speed ADC, a clock configuration, and a management module. The powerful FPGA carrier board is a commercial high-performance Xilinx Kintex-7 FPGA evaluation board. To achieve clock and data alignment for ADC data capture at a high sampling rate, we used ISERDES, IDELAY, and dedicated carry-in resources in the Kintex-7 FPGA. This paper presents a detailed development of the readout electronics in the BAM system and its performance. 展开更多
关键词 BUNCH arrival-time monitor (BAM) Shanghai Soft X-ray Free Electron Laser (SXFEL) Fieldprogrammable gate array (FPGA) Signal CONDITIONING High-speed analog-to-digital converter (ADC)
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Tandem pore TWIK-related potassium channels and neuroprotection 预览
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作者 J. Antonio Lamas Diego Fernandez-Fernandez 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第8期1293-1308,共16页
TWIK-related potassium channels (TREK) belong to a subfamily of the two-pore domain potassium channels family with three members, TREK1, TREK2 and TWIK-related arachidonic acid-activated potassium channels. The two-po... TWIK-related potassium channels (TREK) belong to a subfamily of the two-pore domain potassium channels family with three members, TREK1, TREK2 and TWIK-related arachidonic acid-activated potassium channels. The two-pore domain potassium channels is the last big family of channels being discovered, therefore it is not surprising that most of the information we know about TREK channels predominantly comes from the study of heterologously expressed channels. Notw让hstanding, in this review we pay special attention to the limited amount of information available on native TREK-like channels and real neurons in relation to neuroprotection. Mainly we focus on the role of free fatty acids, lysophospholipids and other neuroprotective agents like riluzole in the modulation of TREK channels, emphasizing on how important this modulation may be for the development of new therapies against neuropathic pain, depression, schizophrenia, epilepsy, ischemia and cardiac complications. 展开更多
关键词 TREK channels TREK-1 TREK-2 TRAAK NEUROPROTECTION free fatty acids lysophospholipids RILUZOLE
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美国石油开采由盛及衰?
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作者 Kevin Crowley David Wethe +1 位作者 Rachel Adams-Hleard 永年(译) 《商业周刊(中文版)》 2019年第1期28-32,共5页
二叠纪盆地石油开采热潮没有被欧佩克扼杀,但它会因为劳动力短缺而消退吗?2018年8月,在得克萨斯州西部的彭威尔市,晚上10点半了,气温还有29℃,69岁的修理工唐·萨格斯(Don Suggs)正在一个废弃的卡车停车场前院敲打着一辆18轮大卡车... 二叠纪盆地石油开采热潮没有被欧佩克扼杀,但它会因为劳动力短缺而消退吗?2018年8月,在得克萨斯州西部的彭威尔市,晚上10点半了,气温还有29℃,69岁的修理工唐·萨格斯(Don Suggs)正在一个废弃的卡车停车场前院敲打着一辆18轮大卡车的车架。收音机里大声传来林纳史金纳合唱团(Lynyrd Skynyrd)的歌曲《Free Bird》。 展开更多
关键词 石油开采 美国 劳动力短缺 得克萨斯州 Free 欧佩克 修理工 停车场
Investigation of the Effects of Baffles on the Shallow Water Sloshing in A Rectangular Tank Using A 2D Turbulent ISPH Method 预览
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作者 Rahim SHAMSODDINI Bahador ABOLPUR 《中国海洋工程:英文版》 SCIE EI CSCD 2019年第1期94-102,共9页
Liquid sloshing is a common phenomenon in the liquid tanks transportation.Liquid waves lead to fluctuating forces on the tank wall.Uncontrolled fluctuations lead to large forces and momentums.Baffles can control these... Liquid sloshing is a common phenomenon in the liquid tanks transportation.Liquid waves lead to fluctuating forces on the tank wall.Uncontrolled fluctuations lead to large forces and momentums.Baffles can control these fluctuations.A numerical method,which has been widely used to model this phenomenon,is Smoothed Particle Hydrodynamics(SPH).The Lagrangian nature of this method makes it suitable for simulating free surface flows.In the present study,an accurate Incompressible Smoothed Particle Hydrodynamics(ISPH)method is developed and improved using the kernel gradient correction tensors,particle shifting algorithms,k–εturbulence model,and free surface particle detectors.Comparisons with the experimental data approve the ability of the present algorithm for simulating shallow water sloshing.The main aim of this study is to investigate the effects of the vertical baffle on the damping of liquid sloshing.Results show that baffles number has a major role in sloshing fluctuation damping. 展开更多
关键词 SPH k–ε vertical BAFFLE SHALLOW water SLOSHING free surface
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游离髂腹股沟皮瓣修复手部皮肤软组织缺损
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作者 戚建武 孙斌鸿 +7 位作者 刘林海 柴益铜 黄剑 方炫量 范学锴 孙赫阳 王欣 陈宏 《中华手外科杂志》 CSCD 北大核心 2019年第1期12-15,共4页
目的探讨个性化游离髂腹股沟皮瓣修复手部皮肤软组织缺损的临床疗效。方法自2013年1月至2017年12月,我们采用游离髂腹股沟皮瓣移植修复手部皮肤软组织缺损患者97例,其中旋髂浅动脉皮瓣63例(带髂骨的旋髂浅动脉复合皮瓣26例),腹壁浅动脉... 目的探讨个性化游离髂腹股沟皮瓣修复手部皮肤软组织缺损的临床疗效。方法自2013年1月至2017年12月,我们采用游离髂腹股沟皮瓣移植修复手部皮肤软组织缺损患者97例,其中旋髂浅动脉皮瓣63例(带髂骨的旋髂浅动脉复合皮瓣26例),腹壁浅动脉皮瓣15例,旋髂浅动脉和腹壁浅动脉联合皮瓣19例(分叶皮瓣7例)。皮肤缺损面积为4 cm×6 cm~11 cm×23 cm。术中皮瓣动脉与桡动脉终末支端端吻合5例,与桡动脉端侧吻合58例,与尺动脉端侧吻合20例,与指总动脉吻合14例;全部修复旋髂浅静脉或腹壁浅静脉(31例同时修复一根伴行静脉)。供区通过屈髋屈膝后均予直接缝合,无需植皮。术后3周、1.5个月、3个月、6个月、1年、2年随访观察供区的愈合情况及受区皮瓣外观和感觉恢复情况。结果97例皮瓣中94例顺利存活,术后1例皮瓣出现动脉危象、2例出现静脉危象,2例手术探查、1例保守治疗后1例顺利存活、2例皮肤坏死,二期切痂后发现皮下软组织成活,予全厚皮片植皮修复。腹部供区有1例联合皮瓣术后1周直立行走出现切口裂开,经二期缝合后愈合;余供区均Ⅰ期愈合。随访时间为0.5~1.5年,皮瓣质地软,轻度臃肿,感觉恢复至S2~S3,腹部供区仅留线性瘢痕。结论根据手部受区皮肤软组织缺损情况,采用个性化游离髂腹股沟皮瓣移植修复能满足受区的不同需要。并且供区隐蔽,切取面积大,能直接缝合,属于轴形皮瓣,血管恒定,切取方便,不破坏主要血管,手术时间短,因此是修复四肢皮肤软组织缺损较理想的方法之一。 展开更多
关键词 手损伤 外科皮瓣 皮肤软组织缺损 游离 个性化
论《儒林外史》中的反抗实践及其可能 预览
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作者 路文彬 《枣庄学院学报》 2019年第4期61-70,共10页
《儒林外史》是中国文学史上第一部拥有自觉反抗意识的作品,反抗本身即意味着某种个体意识的觉醒。但反抗的指归不是破坏和说不,乃是恢复和说是。《儒林外史》中人物之于现世权力的反抗实质上就是之于古礼的服从,只是由于这种古礼往往... 《儒林外史》是中国文学史上第一部拥有自觉反抗意识的作品,反抗本身即意味着某种个体意识的觉醒。但反抗的指归不是破坏和说不,乃是恢复和说是。《儒林外史》中人物之于现世权力的反抗实质上就是之于古礼的服从,只是由于这种古礼往往拘于外在规则,因而无法落实为主体的内在美德,导致他们的反抗试图恢复的并非真正的自由,结果等待他们的就不可能是成功。 展开更多
关键词 《儒林外史》 反抗 自由
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蚌埠市9888名女性免费婚检结果分析 预览
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作者 张睿 李娜 彭蓉蓉 《淮海医药》 CAS 2019年第4期345-348,共4页
目的:分析蚌埠市2017—2018年免费婚检对象中所有女性受检者9888人的相关资料,探讨蚌埠市女性婚前健康状况,以期提升婚检服务质量和优生优育服务水平。方法:对9888名女性参加免费婚检检出疾病等情况进行统计分析。结果:蚌埠市2017年和2... 目的:分析蚌埠市2017—2018年免费婚检对象中所有女性受检者9888人的相关资料,探讨蚌埠市女性婚前健康状况,以期提升婚检服务质量和优生优育服务水平。方法:对9888名女性参加免费婚检检出疾病等情况进行统计分析。结果:蚌埠市2017年和2018年婚前医学检查率超过80%,9888名女性受检者疾病总检出率为27.78%,前十位分别为:乳腺囊性增生、阴道炎、贫血、乙肝病毒携带、尿路感染、高血压病、心动过速、隐性梅毒、乳房肿瘤、盆腔附件包块;女性婚检HBsAg阳性率为2.87%,2年婚检阳性率比较,差异有统计学意义(P<0.05),呈下降趋势,女性婚检中抗-TP阳性率为0.44%,2年阳性率比较差异无统计学意义(P>0.05),女性受检者抗-HIV阳性检出者2年均为0;参加免费婚检时20.52%女性处于妊娠期,2年婚前妊娠率比较,差异有统计学意义(P<0.05),呈上升趋势。结论:蚌埠市免费婚检对女性影响婚育疾病的检出效果显著,需要继续加大免费婚检宣传力度,使宣教人群年轻化。婚检机构要重视病例讨论和阳性病例的追踪随访,不断提升婚检医师的疾病检出能力和咨询指导水平。 展开更多
关键词 婚前医学检查 免费 女性
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Effect of crystalline structure on terbuthylazine degradation by H2O2-assisted TiO2 photocatalysis under visible irradiation
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作者 Jianjun Tang Yiqing Chen Zijun Dong 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第5期153-160,共8页
Various methods for shifting the optical response of TiO2 into the visible(Vis) range have been reported. Herein, we reported the application of a TiO2/H2O2/Vis process and the effects of TiO2 crystalline structure on... Various methods for shifting the optical response of TiO2 into the visible(Vis) range have been reported. Herein, we reported the application of a TiO2/H2O2/Vis process and the effects of TiO2 crystalline structure on the degradation of terbuthylazine. The results indicated that TiO2 crystalline structure and H2O2 addition had significant effects on terbuthylazine degradation: its degradation rate could be increased from 7% to 70% with H2O2 addition after 180 min of reaction, the synergistic degradation of terbuthylazine by TiO2-Fe3+ was substantially accelerated, with the degradation rate reaching up to 100% after20 min of reaction, and rutile TiO2 showed better photocatalytic activity and a more obvious synergistic effect than anatase TiO2. The addition of free-radical scavengers(tert-butyl alcohol or methanol) inhibited the degradation efficiency of rutile TiO2, but had a relatively minor effect on anatase TiO2. Fluorescence spectrophotometry analysis indicated that hydroxyl free radicals could be continuously produced when using rutile TiO2 as the photocatalyst. Degradation of terbuthylazine catalyzed by rutile TiO2 occurred mainly in solution, but occurred on the particle surface of the photocatalyst when catalyzed by anatase TiO2. This study provides new insight into the role of TiO2 crystalline structure on the degradation of terbuthylazine and its photocatalytic degradation mechanism. 展开更多
关键词 VISIBLE-LIGHT PHOTOCATALYSIS Reaction pathway HYDROXYL free RADICAL Hydrogen PEROXIDE
Differences in pathological changes between two rat models of severe traumatic brain injury 预览
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作者 Yi-Ming Song Yu Qian +6 位作者 Wan-Qiang Su Xuan-Hui Liu Jin-Hao Huang Zhi-Tao Gong Hong-Liang Luo Chuang Gao Rong-Cai Jiang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第10期1796-1804,共9页
The rat high-impact free weight drop model mimics the diffuse axonal injury caused by severe traumatic brain injury in humans,while severe controlled cortical impact can produce a severe traumatic brain injury model u... The rat high-impact free weight drop model mimics the diffuse axonal injury caused by severe traumatic brain injury in humans,while severe controlled cortical impact can produce a severe traumatic brain injury model using precise strike parameters.In this study,we compare the pathological mechanisms and pathological changes between two rat severe brain injury models to identify the similarities and differences.The severe controlled cortical impact model was produced by an electronic controlled cortical impact device,while the severe free weight drop model was produced by dropping a 500 g free weight from a height of 1.8 m through a plastic tube.Body temperature and mortality were recorded,and neurological deficits were assessed with the modified neurological severity score.Brain edema and bloodbrain barrier damage were evaluated by assessing brain water content and Evans blue extravasation.In addition,a cytokine array kit was used to detect inflammatory cytokines.Neuronal apoptosis in the brain and brainstem was quantified by immunofluorescence staining.Both the severe controlled cortical impact and severe free weight drop models exhibited significant neurological impairments and body temperature fluctuations.More severe motor dysfunction was observed in the severe controlled cortical impact model,while more severe cognitive dysfunction was observed in the severe free weight drop model.Brain edema,inflammatory cytokine changes and cortical neuronal apoptosis were more substantial and blood-brain barrier damage was more focal in the severe controlled cortical impact group compared with the severe free weight drop group.The severe free weight drop model presented with more significant apoptosis in the brainstem and diffused blood-brain barrier damage,with higher mortality and lower repeatability compared with the severe controlled cortical impact group.Severe brainstem damage was not found in the severe controlled cortical impact model.These results indicate that the severe controlled cortical impact model is relat 展开更多
关键词 nerve REGENERATION severe traumatic brain INJURY animal model comparison free weight drop controlled cortical impact NEUROLOGICAL impairment NEUROINFLAMMATION blood-brain barrier damage neuronal apoptosis diffuse AXONAL INJURY BRAINSTEM INJURY neural REGENERATION
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An Electrochemical Cinnamyl C—H Amination Reaction Using Carbonyl Sulfamate
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作者 Shuai Liu Jin Li +5 位作者 Dalin Wang Feng Liu Xu Liu Yongyuan Gao Dai Jie Xu Cheng 《中国化学:英文版》 SCIE CAS CSCD 2019年第6期570-574,共5页
An electrochemical cinnamyl C—H amination reaction in the absence of transition metal catalyst and oxidant was reported. The choice of carbonyl sulfamate as nitrogen source is the key to achieve desired chemoselectiv... An electrochemical cinnamyl C—H amination reaction in the absence of transition metal catalyst and oxidant was reported. The choice of carbonyl sulfamate as nitrogen source is the key to achieve desired chemoselectivity. A series of terminal amine derivatives are prepared using this protocol and the sulfonyl group can be removed with basic hydrolysis. The reaction is suggested to proceed via a continuous anodic oxidation, deprotonation, anodic oxidation, and intermolecular nucleophilic addition pathway, demonstrating the first example of electrochemical cinnamyl C—H amination. 展开更多
关键词 ELECTROCHEMISTRY C-H AMINATION SULFAMATE catalyst free
Dietary approach and gut microbiota modulation for chronic hepatic encephalopathy in cirrhosis 预览
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作者 Daniela Campion Ilaria Giovo +3 位作者 Paola Ponzo Giorgio M Saracco Federico Balzola Carlo Alessandria 《世界肝病学杂志:英文版(电子版)》 2019年第6期489-512,共24页
Hepatic encephalopathy(HE)is a common and serious neuropsychiatric complication of cirrhosis,acute liver failure,and porto-systemic shunting.HE largely contributes to the morbidity of patients with liver disease,sever... Hepatic encephalopathy(HE)is a common and serious neuropsychiatric complication of cirrhosis,acute liver failure,and porto-systemic shunting.HE largely contributes to the morbidity of patients with liver disease,severely affecting the quality of life of both patients and their relatives and being associated with poor prognosis.Its presentation is largely variable,manifesting with a broad spectrum of cognitive abnormalities ranging from subtle cognitive impairment to coma.The pathogenesis of HE is complex and has historically been linked with hyperammonemia.However,in the last years,it has become evident that the interplay of multiple actors,such as intestinal dysbiosis,gut hyperpermeability,and neuroinflammation,is of crucial importance in its genesis.Therefore,HE can be considered a result of a dysregulated gut-liverbrain axis function,where cognitive impairment can be reversed or prevented by the beneficial effects induced by“gut-centric”therapies,such as non-absorbable disaccharides,non-absorbable antibiotics,probiotics,prebiotics,and fecal microbiota transplantation.In this context dietary modifications,by modulating the intestinal milieu,can also provide significant benefit to cirrhotic patients with HE.This review will provide a comprehensive insight into the mechanisms responsible for gut-liver-brain axis dysregulation leading to HE in cirrhosis.Furthermore,it will explore the currently available therapies and the most promising future treatments for the management of patients with HE,with a special focus on the dietary approach. 展开更多
关键词 CIRRHOSIS Hepatic encephalopathy DIET therapy GUT MICROBIOTA Leaky GUT HYPERAMMONEMIA Prebiotics Probiotics Gluten-casein free DIET GUT MICROBIOTA transplantation
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gt-C3N4 coordinated single atom as an efficient electrocatalyst for nitrogen reduction reaction
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作者 Lifu Zhang Wanghui Zhao +2 位作者 Wenhua Zhang Jing Chen Zhenpeng Hu 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第5期1181-1186,共6页
The electrochemical reduction of nitrogen to ammonia is a promising way to produce ammonia at mild condition.The design and preparation of an efficient catalyst with high ammonia selectivity is critical for the real a... The electrochemical reduction of nitrogen to ammonia is a promising way to produce ammonia at mild condition.The design and preparation of an efficient catalyst with high ammonia selectivity is critical for the real applications.In this work,a series of transition metal (TM =Sc,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,Y,Zr,Nb,Mo,Tc,Ru,Rh,Pd,Ag,and Cd) atoms supported by gt-C3N4 (TM/gt-C3N4) are investigated as electrocatalysts for the nitrogen reduction reaction (NRR) based on density functional calculations.It is found that Mo/gt-C3N4 with a limiting potential of-0.82 V is the best catalyst for standing-on adsorbed N2 cases.While for lying-on adsorbed N2 cases,V/gt-C3N4 with a limiting potential of-0.79 V is berer than other materials.It is believed that this work provides several promising candidates for the non-noble metal electrocatalysts for NRR at mild condition. 展开更多
关键词 NITROGEN reduction reaction SINGLE-ATOM catalyst FIRST-PRINCIPLES calculation Gibbs free energy
Heavy metal free primers: Polymorphism of gadolinium and titanium in the context of GSR glass phase 预览
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作者 Felice Nunziata 《Defence Technology(防务技术)》 CAS CSCD 2019年第3期272-275,共4页
The possibility of identifying gunshot residue (GSR) particles produced by non-toxic primers containing only titanium and zinc is a very difficult task using SEM/EDX analysis employed in the analysis of GSR originatin... The possibility of identifying gunshot residue (GSR) particles produced by non-toxic primers containing only titanium and zinc is a very difficult task using SEM/EDX analysis employed in the analysis of GSR originating from primers containing lead, barium and antimony. However, Bauer et al. demonstrated that non-toxic (TieZn) primers form a TiZn2O4 spinel crystalline structure using SEM/EDX with EBSD (Electron Back Scatter Diffraction) and TKD (Transmission Kikuchi Diffraction), whereas GSR originating from gadolinium-doped TieZn primers form a non-crystalline glass phase. Here, a possible explanation of these different phenomena is hypothesized. 展开更多
关键词 GSR Heavy metal free PRIMERS GADOLINIUM Glass phase EBSD TKD
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Eligibility Criteria for Legal Aid: Comparative Analysis 预览
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作者 Anzelika Baneviciene 《美中法律评论:英文版》 2019年第3期83-96,共14页
The free movement of people guaranteed in the EU encourages people to move their place of residence from one Member State to another. It is essential to ensure equal protection of their rights in all EU countries. Pro... The free movement of people guaranteed in the EU encourages people to move their place of residence from one Member State to another. It is essential to ensure equal protection of their rights in all EU countries. Protection of the right to access to justice cannot be ensured without an effective legal aid provision to economically disadvantaged and vulnerable groups of people. EU countries are all very different, and so too is the regulation of their national systems of legal aid. The article provides an overview of 14 EU countries—Lithuania, Germany, Netherland, Spain, France, Belgium, Italy, Denmark, Poland, Sweden, Finland, Hungary, Ireland, and UK (England & Wales, Scotland, and Northern Ireland), identifying similarities and differences in the assessment of person’s eligibility for the legal aid in civil cases. 展开更多
关键词 free LEGAL AID state-funded LEGAL AID ELIGIBILITY criteria means and MERIT test FIRST-LINE LEGAL AID SECOND-LINE LEGAL AID
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Thermodynamics of NaHCO3 decomposition during Na2CO3-based CO2 capture
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作者 Sam Toan William O’Dell +5 位作者 Christopher K.Russell Sun Zhao Qinghua Lai Huiping Song Ying Zhao Maohong Fan 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第4期74-80,共7页
Amine-basedcarbon-capture technologies have been shown to be energetically expensive and to cause significant environmental and epidemiological impacts due to their volatility.Bicarbonate formation from carbon dioxide... Amine-basedcarbon-capture technologies have been shown to be energetically expensive and to cause significant environmental and epidemiological impacts due to their volatility.Bicarbonate formation from carbon dioxide’s reaction with water has been suggested as an effective alternative for capturing CO2;however,the thermodynamics of this reaction are not well understood.This study experimentally determined the equilibrium constant of sodium bicarbonate(Na HCO3)decomposition to sodium,water,and carbon dioxide;the study also compared the equilibrium constant to theoretical calculations.Using a combination of experimentation and thermodynamic relationships,the unitless equilibrium constants of the forward and reverse reactions were calculated accurately(error<±9%and<±4%,respectively).Equilibrium data were calculated using enthalpy and entropy values of each component of Na HCO3decomposition at temperatures ranging from 25 to 155°C respectively.These results offer more data essential to optimizing Na HCO3use in environmentally friendly nextgeneration CO2-capture technologies. 展开更多
关键词 SODIUM BICARBONATE SODIUM carbonate Gibbs free energy ENTHALPY Entropy
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