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B-site ion regulation strategy enables performance optimization and multifunctional integration of hybrid perovskite ferroelectrics
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作者 Hao-Fei Ni Jia-He Lin +7 位作者 Gele Teri Qiang-Qiang Jia Pei-Zhi Huang Hai-Feng Lu Chang-Feng Wang Zhi-Xu Zhang Da-Wei Fu Yi Zhang 《Chinese Chemical Letters》 2025年第3期555-559,共5页
The performance optimization of materials is an eternal theme and challenge in scientific research,which is reflected in ferroelectric filed to two hot topics of enhancing Curie temperature(TC)and functional versatili... The performance optimization of materials is an eternal theme and challenge in scientific research,which is reflected in ferroelectric filed to two hot topics of enhancing Curie temperature(TC)and functional versatility.The former one vitally determines ferroelectric operational temperature range while the latter would open up new application possibilities.Effective chemical modification or doping strategies on A-site and X-site components have been successfully developed in hybrid organic-inorganic perovskite(HOIP)ferroelectrics,however,the important role of adjusting B-site ions has long been overlooked.Here,we have implemented regulation on the ion radius of the B-site component to successfully obtain two new HOIP ferroelectrics(3-pyrrolinium)BBr_(3)(B=Mn and Ni).Compared to parent(3-pyrrolinium)CdBr_(3),the TC(△T=99 K)was significantly optimized by replacing the Cd^(2+)with smaller Mn^(2+)or Ni^(2+)ions.More strikingly,the introduction of Mn^(2+)and Ni^(2+)ions with octahedral coordination bring out intriguing red emission and magnetism respectively,making the multifunctional integration in a single material for multiple uses.This work provides a feasible strategy for performance optimizing of HOIP ferroelectrics,and would shed light for constructing multifunctional ferroelectrics. 展开更多
关键词 FERROELECTRIC Hybrid perovskites Crystal engineering Curie temperature Phase transition
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Discovering causal models for structural,construction and defense-related engineering phenomena
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作者 M.Z.Naser 《Defence Technology(防务技术)》 2025年第1期60-79,共20页
Causality,the science of cause and effect,has made it possible to create a new family of models.Such models are often referred to as causal models.Unlike those of mathematical,numerical,empirical,or machine learning(M... Causality,the science of cause and effect,has made it possible to create a new family of models.Such models are often referred to as causal models.Unlike those of mathematical,numerical,empirical,or machine learning(ML)nature,causal models hope to tie the cause(s)to the effect(s)pertaining to a phenomenon(i.e.,data generating process)through causal principles.This paper presents one of the first works at creating causal models in the area of structural and construction engineering.To this end,this paper starts with a brief review of the principles of causality and then adopts four causal discovery algorithms,namely,PC(Peter-Clark),FCI(fast causal inference),GES(greedy equivalence search),and GRa SP(greedy relaxation of the sparsest permutation),have been used to examine four phenomena,including predicting the load-bearing capacity of axially loaded members,fire resistance of structural members,shear strength of beams,and resistance of walls against impulsive(blast)loading.Findings from this study reveal the possibility and merit of discovering complete and partial causal models.Finally,this study also proposes two simple metrics that can help assess the performance of causal discovery algorithms. 展开更多
关键词 CAUSALITY Causal discovery Directed acyclic graphs Machine learning Metrics
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Enhanced output power density of PVDF/LM composite for piezoelectric sensor
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作者 Qiang-Qiang Jia Jia-Qi Luo +7 位作者 Zhi-Yu Xue Jing-Song Tang Wen-Qiang Qiu Chang-Feng Wang Zhi-Xu Zhang Hai-Feng Lu Yi Zhang Da-Wei Fu 《Chinese Chemical Letters》 2025年第11期535-540,共6页
Poly(vinylidene fluoride)(PVDF)based piezoelectric materials have received tremendous scientific attention for many decades.However,the high output power density remains a significant challenge and an area of intense ... Poly(vinylidene fluoride)(PVDF)based piezoelectric materials have received tremendous scientific attention for many decades.However,the high output power density remains a significant challenge and an area of intense interest.Herein,we present a piezoelectric sensor with high output power density by incorporating liquid metal(LM)microdroplets into PVDF piezoelectric substrate.Remarkably,the LM/PVDF composite showed theβ-phase content above 90%and the output power density is enhanced to 353μW/cm^(2),nearly 1000 times higher than that of pure PVDF materials and significantly surpassing other PVDF-based composite materials.These exceptional performances are attributed to two key factors:The formation of a liquid-solid/electric-dielectric interface between the LM and PVDF,and the incorporation of the LM's outstanding charge transfer capability.This work might present an effective strategy for advancing the utilization of PVDF-based piezoelectric materials in compelling applications within the realm of intelligent wearable electronics. 展开更多
关键词 PVDF Liquid metal PIEZOELECTRIC FERROELECTRIC Flexible self-powered sensing
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Advancements in remote sensing techniques for earthquake engineering:A review
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作者 Chinmayi H.K K.Colton Flynn Amanda J.Ashworth 《Earthquake Research Advances》 2025年第3期110-122,共13页
Remote sensing technologies play a vital role in our understanding of earthquakes and their impact on the Earth's surface.These technologies,including satellite imagery,aerial surveys,and advanced sensors,contribu... Remote sensing technologies play a vital role in our understanding of earthquakes and their impact on the Earth's surface.These technologies,including satellite imagery,aerial surveys,and advanced sensors,contribute significantly to our understanding of the complex nature of earthquakes.This review highlights the advancements in the integration of remote sensing technologies into earthquake studies.The combined use of satellite imagery and aerial photography in conjunction with geographic information systems(GIS)has been instrumental in showcasing the significance of fusing various types of satеllitеdata sourcеs for comprеhеnsivееarthquakеdamagеassеssmеnts.However,remote sensing encounters challenges due to limited pre-event imagery and restricted postearthquake site access.Furthеrmorе,thеapplication of dееp-lеarning mеthods in assеssingеarthquakе-damagеd buildings dеmonstratеs potеntial for furthеr progrеss in this fiеld.Overall,the utilization of remote sensing technologies has greatly enhanced our comprehension of earthquakes and their effects on the Earth's surface.The fusion of remote sensing technology with advanced data analysis methods holds tremendous potential for driving progress in earthquake studies and damage assessment. 展开更多
关键词 Remote sensing Earthquake engineering Satellite imagery Machine learning dееp-lеarning mеthods
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An Overview of Dynamic Descriptions for Nanoscale Materials in Particulate Photocatalytic Systems from Spatiotemporal Perspectives
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作者 Jiawei Yan Zhidong Wei +4 位作者 Kai Takagi Masaya Motodate Zhi Jiang Chiaki Terashima Wenfeng Shangguan 《Nano-Micro Letters》 2025年第8期416-448,共33页
Particulate photocatalytic systems using nanoscale photocatalysts have been developed as an attractive promising route for solar energy utilization to achieve resource sustainability and environmental harmony.Dynamic ... Particulate photocatalytic systems using nanoscale photocatalysts have been developed as an attractive promising route for solar energy utilization to achieve resource sustainability and environmental harmony.Dynamic obstacles are considered as the dominant inhibition for attaining satisfactory energy-conversion efficiency.The complexity in light absorption and carrier transfer behaviors has remained to be further clearly illuminated.It is challenging to trace the fast evolution of charge carriers involved in transfer migration and interfacial reactions within a micro–nano-single-particle photocatalyst,which requires spatiotemporal high resolution.In this review,comprehensive dynamic descriptions including irradiation field,carrier separation and transfer,and interfacial reaction processes have been elucidated and discussed.The corresponding mechanisms for revealing dynamic behaviors have been explained.In addition,numerical simulation and modeling methods have been illustrated for the description of the irradiation field.Experimental measurements and spatiotemporal characterizations have been clarified for the reflection of carrier behavior and probing detection of interfacial reactions.The representative applications have been introduced according to the reported advanced research works,and the relationships between mechanistic conclusions from variable spatiotemporal measurements and photocatalytic performance results in the specific photocatalytic reactions have been concluded.This review provides a collective perspective for the full understanding and thorough evaluation of the primary dynamic processes,which would be inspired for the improvement in designing solar-driven energy-conversion systems based on nanoscale particulate photocatalysts. 展开更多
关键词 Dynamic description Particulate photocatalytic system Nanoscale photocatalyst Spatiotemporal characterization
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Inter-layer interference for multi-layered tight gas reservoir in the absence and presence of movable water 被引量:3
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作者 Tao Zhang Bin-Rui Wang +5 位作者 Yu-Long Zhao Lie-Hui Zhang Xiang-Yang Qiao Lei Zhang Jing-Jing Guo Hung Vo Thanh 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1751-1764,共14页
Due to the dissimilarity among different producing layers,the influences of inter-layer interference on the production performance of a multi-layer gas reservoir are possible.However,systematic studies of inter-layer ... Due to the dissimilarity among different producing layers,the influences of inter-layer interference on the production performance of a multi-layer gas reservoir are possible.However,systematic studies of inter-layer interference for tight gas reservoirs are really limited,especially for those reservoirs in the presence of water.In this work,five types of possible inter-layer interferences,including both absence and presence of water,are identified for commingled production of tight gas reservoirs.Subsequently,a series of reservoir-scale and pore-scale numerical simulations are conducted to quantify the degree of influence of each type of interference.Consistent field evidence from the Yan'an tight gas reservoir(Ordos Basin,China)is found to support the simulation results.Additionally,suggestions are proposed to mitigate the potential inter-layer interferences.The results indicate that,in the absence of water,commingled production is favorable in two situations:when there is a difference in physical properties and when there is a difference in the pressure system of each layer.For reservoirs with a multi-pressure system,the backflow phenomenon,which significantly influences the production performance,only occurs under extreme conditions(such as very low production rates or well shut-in periods).When water is introduced into the multi-layer system,inter-layer interference becomes nearly inevitable.Perforating both the gas-rich layer and water-rich layer for commingled production is not desirable,as it can trigger water invasion from the water-rich layer into the gas-rich layer.The gas-rich layer might also be interfered with by water from the neighboring unperforated water-rich layer,where the water might break the barrier(eg weak joint surface,cement in fractures)between the two layers and migrate into the gas-rich layer.Additionally,the gas-rich layer could possibly be interfered with by water that accumulates at the bottom of the wellbore due to gravitational differentiation during shut-in operations. 展开更多
关键词 Tight gas Comingled production INTERFERENCE Two-phase flow Water blocking
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Outcome of the efficacy of Chinese herbal medicine for functional constipation:A systematic review and meta-analysis 被引量:7
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作者 Zipan Lyu Yibo Fan +3 位作者 Yang Bai Tao Liu Linda LD Zhong Hui-Feng Liang 《World Journal of Clinical Cases》 SCIE 2022年第15期4856-4877,共22页
BACKGROUND Functional constipation(FC)is a common and chronic gastrointestinal disease and its treatment remains challenging.AIM To evaluate the efficacy and safety of Chinese herbal medicine(CHM)on efficacy rate,glob... BACKGROUND Functional constipation(FC)is a common and chronic gastrointestinal disease and its treatment remains challenging.AIM To evaluate the efficacy and safety of Chinese herbal medicine(CHM)on efficacy rate,global symptoms,bowel movements and the Bristol Stool Scale score in patients with FC by summarizing current available randomized controlled trials(RCTs).METHODS RCTs with CHM to treat FC were identified by a systematic search of six databases from inception to October 20,2020.Two independent reviewers assessed the quality of the included articles and extracted data.Meta-analyses were performed to odds ratio(OR),mean differences(MD)and 95%confidence interval(CI)using random-effects models.Subgroup analyses and sensitivity analyses were used to explore and interpret the sources of heterogeneity.The funnel plot,Begg’s test and Egger’s test were used to detect publication bias.RESULTS Ninety-seven studies involving 8693 patients were included in this work.CHM was significantly associated with a higher efficacy rate(OR:3.62,95%CI:3.19-4.11,P<0.00001)less severe global symptoms(OR:4.03,95%CI:3.49-4.65,P<0.00001)compared with control treatment,with the low heterogeneity between studies(I2=0%,P=0.76).CHM was also associated with more frequent bowel movements(MD 0.83,95%CI:0.67-0.98,P<0.00001),a lower score on the Bristol Stool Scale(OR:1.63,95%CI:1.15-2.32,P<0.006),and a not significant recurrence rate(OR:0.47,95%CI:0.22-0.99,P=0.05).No serious adverse effects of CHM were reported.CONCLUSION In this meta-analysis,we found that CHM may have potential benefits in increasing the number of bowel movements,improving stool characteristics and alleviating global symptoms in FC patients.However,a firm conclusion could not be reached because of the poor quality of the included trials.Further trials with higher quality are required. 展开更多
关键词 Functional constipation Chinese herbal medicine EFFICACY Systematic review META-ANALYSIS
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The Mg-carbonate-Fe interaction:Implication for the fate of subducted carbonates and formation of diamond in the lower mantle 被引量:4
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作者 Naira S.Martirosyan Konstantin D. Litasov +4 位作者 Sergey S. Lobanov Alexander F. Goncharov Anton Shatskiy Hiroaki Ohfuji Vitali Prakapenka 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1449-1458,共10页
The fate of subducted carbonates in the lower mantle and at the core-mantle boundary was modelled via experiments in the MgCO3-Fe^0 system at 70-150 GPa and 800-2600 Kin a laser-heated diamond anvil cell.Using in situ... The fate of subducted carbonates in the lower mantle and at the core-mantle boundary was modelled via experiments in the MgCO3-Fe^0 system at 70-150 GPa and 800-2600 Kin a laser-heated diamond anvil cell.Using in situ synchrotro n X-ray diffraction and ex situ transmission electron microscopy we show that the reduction of Mg-carbonate can be exemplified by:6 MgCO3+19 Fe=8 FeO+10(Mg0.6Fe^0.4)O+Fe7 C3+3 C.The presented results suggest that the interaction of carbonates with Fe^0 or Fe^0-bearing rocks can produce Fe-carbide and diamond,which can accumulate in the D"region,depending on its carbon to Fe ratio.Due to the sluggish kinetics of the transformation,diamond can remain metastable at the core-mantle boundary(CMB)unless it is in a direct contact with Fe-metal.In addition,it can be remobilized by redox melting accompanying the generation of mantle plumes. 展开更多
关键词 Deep carbon cycle CARBONATE CARBIDE High pressure Redox reaction
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Vitellaria paradoxa nutshells from seven sub-Saharan countries as potential herbal medicines for treating diabetes based on chemical compositions, HPLC fingerprints and bioactivity evaluation 被引量:2
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作者 LI Da XIAO Jian-Qi +7 位作者 LIU Wen-Yuan ZHANG Chao-Feng AKIHISA Toshihiro ABE Masahiko MASTERS Eliot-T. ZHAI Wei-Wei FENG Feng ZHANG Jie 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2019年第6期446-460,共15页
The aim of the study was to determine the feasibility of the Vitellaria paradoxa nutshell as a new medicinal resource for treating diabetes. A total of forty-one compounds were identified by HPLC-DAD-Q-TOF-MS and phyt... The aim of the study was to determine the feasibility of the Vitellaria paradoxa nutshell as a new medicinal resource for treating diabetes. A total of forty-one compounds were identified by HPLC-DAD-Q-TOF-MS and phytochemical methods in V. paradoxa nutshell methanol extract. Based on HPLC fingerprints, four characteristic constituents were quantified and the origin of twenty-eight V. paradoxa nutshells from seven sub-Saharan countries was compared, which were classified into three groups with chemometric method. Twenty-eight samples contained high total phenolic content, and exhibited moderate-higher antioxidant activity and strong α-glucosidase inhibitory activity. Furthermore, all fractions and isolated compounds were evaluated for their antioxidant and α-glucosidase inhibitory activities, and α-glucosidase inhibitory action mechanism of four characteristic constituents including protocatechuic acid, 3, 5, 7-trihydroxycoumarin,(2 R, 3 R)-(+)-taxifolin and quercetin was investigated via molecular docking method, which were all stabilized by hydrogen bonds with α-glucosidase. The study provided an effective approach to waste utilization of V. paradoxa nutshell, which would help to resolve waste environmental pollution and provide a basis for developing potential herbal resource for treating diabetes. 展开更多
关键词 Vitellaria paradoxa HPLC FINGERPRINTS Antioxidant ACTIVITY Α-GLUCOSIDASE INHIBITORY ACTIVITY Molecular DOCKING
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A fast powerful X-ray transient from possible tidal disruption of a white dwarf
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作者 Dongyue Li Wenda Zhang +97 位作者 Jun Yang Jin-Hong Chen Weimin Yuan Huaqing Cheng Fan Xu Xinwen Shu Rong-Feng Shen Ning Jiang Jiazheng Zhu Chang Zhou Weihua Lei Hui Sun Chichuan Jin Lixin Dai Bing Zhang Yu-Han Yang Wenjie Zhang Hua Feng Bifang Liu Hongyan Zhou Haiwu Pan Mingjun Liu Stéphane Corbel Sitha KJagan Maria Cristina Baglio Christopher RBurns Floriane Cangemi Chun Chen Yehao Cheng Alexis Coleiro Francesco Coti Zelati Sourya RDas Zhongnan Dong Luis Galbany Noa Grollimund Daniel Kelson Dong Lai Xia Li Yuan Liu Alessio Marino Brenna Mockler Paul O'Brien Erlin Qiao Nanda Rea LResmi Jérome Rodriguez Richard Saxton Luming Sun Lian Tao Tinggui Wang Yilong Wang Xuefeng Wu Dong Xu Yijia Zhang Guoying Zhao Congying Bao Zhiming Cai Yehai Chen Yong Chen Bertrand Cordier Chenzhou Cui Weiwei Cui Zhou Fan He Gao Giancarlo Ghirlanda Ju Guan Dawei Han Jinxin Hao Jingwei Hu Maohai Huang Yong-Feng Huang Shumei Jia Ge Jin Stefanie Komossa Chengkui Li Zhixing Ling Congzhan Liu Heyang Liu Huaqiu Liu Fangjun Lu Kirpal Nandra Jan-Uwe Ness Arne Rau Jeremy Sanders Liming Song Roberto Soria Shengli Sun Xiaojin Sun Yuyin Tan Eleonora Troja Sixiang Wen Haitao Xu Changbin Xue Yongquan Xue Yi-Han Iris Yin Chen Zhang Shuang-Nan Zhang Yonghe Zhang 《Science Bulletin》 2026年第3期538-546,共9页
Stars getting close enough to black holes(BHs)can be torn apart by strong tidal forces,producing electromagnetic flares.To date,more than 100 tidal disruption events(TDEs)have been observed,each involving invariably n... Stars getting close enough to black holes(BHs)can be torn apart by strong tidal forces,producing electromagnetic flares.To date,more than 100 tidal disruption events(TDEs)have been observed,each involving invariably normal gaseous stars whose debris falls onto the BH,sustaining the flares over years.White dwarfs(WDs),which are the most prevalent compact stars and a million times denser-and therefore tougher-than gaseous stars,can only be disrupted by intermediate-mass black holes(IMBHs)of 10^(2)–10^(5) solar masses.WD-TDEs are considered to generate more powerful and short-lived flares,but their evidence has been lacking.Here we report observations of a fast and luminous X-ray transient EP250702a detected by Einstein Probe.Its one-day-long X-ray peak as luminous as 10^(47−49) erg s^(−1) showed strong recurrent flares with hard spectra extending to several tens of MeV gamma-rays,as detected by Fermi/GBM and Konus-Wind,indicating relativistic jet emission.The jet's X-rays dropped sharply from 3×10^(49) erg s^(−1) to around 1044 erg s^(−1) within 20 days(10 days in the source rest frame).These characteristics are inconsistent with any previously known transient phenomena.We suggest that this fast-evolving event over the unprecedentedly short timescale arises likely from disruption of a WD by an IMBH.At late times,a soft component progressively dominates the X-ray spectrum,reaching a luminosity as high as 1044 erg s^(−1),which is consistent with being extreme super-Eddington emission from an accretion disk expected to form in an IMBH-WD TDE.WD-TDEs open a new window for investigating the elusive IMBHs and their surrounding stellar environments,and they are prime sources of gravitational waves in the band of space-based interferometers. 展开更多
关键词 X-ray transient Intermediate-mass black hole Tidal disruption event White dwarf Tianguan Einstein Probe
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Construction, photoelectric response and phase transition for new hybrid double perovskites showing narrow band gaps 被引量:1
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作者 Changyuan Su Zhixu Zhang +5 位作者 Jie Yao Ming Chen Peizhi Huang Yi Zhang Dawei Fu Liyan Xie 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第4期595-600,共6页
To explore the lead-free key scientific issue in perovskite, double perovskite based on Ag Bi and Cu Bi was naturally selected as a competitive candidate due to its fascinating functional features, such as self-powere... To explore the lead-free key scientific issue in perovskite, double perovskite based on Ag Bi and Cu Bi was naturally selected as a competitive candidate due to its fascinating functional features, such as self-powered circularly polarized light detection, X-ray detection, photoluminescence and so on. However, the most challenging point is to simulate the structure and function of traditional lead-based perovskite in new double perovskite. At the same time, there are few suitable double perovskite systems with optical and electrical potential. The above two points greatly limit the competitiveness of double perovskite. In order to solve this problem, firstly, by analyzing and comparing previous studies,we used 2,2-dimethylpropan-1-aminium(abbreviated as 2,2-DPA) as the organic template to assemble materials. Solid-to-solid phase transition materials(2,2-DPA)3Bi2I91 and(2,2-DPA)3Pb2I72 were constructed. Along the path of lead-free and two-dimensional maintenance, we successfully synthesized(2,2-DPA)4AgBiI8.H_(2)O 3 and(2,2-DPA)_(4)CuBiI8.H_(2)O 4. As two typical semiconductors, 3 and 4 with narrower optical band gaps of 1.98 and 1.76 e V show obvious photo-response when the xenon lamp with intensity of 20 m W/cm^(2)is on or off, implying that they may be applied to light-harvesting and light-detecting devices. By referring to the phase transition mechanism of 1 and 2, 3 may be caused by ordered-disordered transition of the organic part, which was proven to be the first solid-to-solid phase transition material with <100>-oriented layered double perovskites with n = 1 by systematic characterization methods after dehydration for all we know. We believed that this work can provide meaningful guidance for the development of lead-free double perovskites. 展开更多
关键词 Double perovskite Photoelectric response Phase transition Dielectric properties Semiconducting behavior
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Evaluation of Thyroid Hormones Levels in Libyan Patients with Chronic Renal Failure before and after Maintenance Hemodialy 被引量:3
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作者 Riad M. Abughalia Milad A. Alrzini Karima R. Zarug Edawib 《Open Journal of Applied Sciences》 2021年第1期11-20,共10页
Data from recent studies revealed that kidney diseases might affect the thyroid function in various ways. A variety of alterations in thyroid hormone levels and metabolism have also been reported in patients with chro... Data from recent studies revealed that kidney diseases might affect the thyroid function in various ways. A variety of alterations in thyroid hormone levels and metabolism have also been reported in patients with chronic renal failure (CRF) in some studied population. In addition, it was reported that serum levels of both T3 and T4 might alter immediately after a hemodialysis (HD) treatment than before. Therefore, this study was aimed to investigate the level of triiodothyronine (T3) and thyroxine (T4) in CRF Libyan patients before and after HD. This study was carried out on 46 CRF patients (30 males and 16 females) with a mean age of 47.46 ± 15.75 years. These patients were treated at the hemodialysis unit of Educational Central Zelitin Hospital, Zelitin, Libya. None of these patients apparently have any thyroid problems and no history of drug intake that may affect thyroid function. Blood samples were taken from each patient to measure serum levels of T3 and T4, before and after HD. In addition, the effects of several variables including age, gender, body mass index (BMI), presence of both hypertension and, diabetes mellitus and duration of kidney dialysis on serum levels of T3 and T4 before and after HD were also studied. After HD, there was a statistically significant increase in the serum levels of T3, T4. The age, gender, BMI, duration of kidney dialysis and the presence of hypertension and diabetes mellitus did not have any significant effect on the serum level of T3 and T4 before and after HD. However, the serum levels of T3 and T4 were still in the normal range in these examined patients either before or after HD. From these findings, it can be concluded that these CRF patients may be in a euthyroid state, because the serum levels of T3 and T4 were in the normal range. In addition, HD was seemed to improve the T3 and T4 thyroid hormone concentrations, suggesting that HD might activate the secretion of thyroid gland and catabolism. The other variables did not play any role in thyroid hormone levels in these patients either before or after HD. It is highly recommended that large scale evaluation of thyroid hormone levels in Libyan CRF patients is performed by more patients, especially elderly patients. 展开更多
关键词 Chronic Renal Failure (CRF) Hemodialysis (HD) Triiodothyronine (T3) and Thyroxine (T4)
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Theory for Charge Density Wave and Orbital-Flux State in Antiferromagnetic Kagome Metal FeGe 被引量:1
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作者 马海洋 殷嘉鑫 +1 位作者 M.Zahid Hasan 刘健鹏 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期90-104,共15页
We theoretically study the charge order and orbital magnetic properties of a new type of antiferromagnetic kagome metal FeGe.Based on first-principles density functional theory calculations,we study the electronic str... We theoretically study the charge order and orbital magnetic properties of a new type of antiferromagnetic kagome metal FeGe.Based on first-principles density functional theory calculations,we study the electronic structures,Fermi-surface quantum fluctuations,as well as phonon properties of the antiferromagnetic kagome metal FeGe.It is found that charge density wave emerges in such a system due to a subtle cooperation between electron-electron interactions and electron–phonon couplings,which gives rise to an unusual scenario of interaction-triggered phonon instabilities,and eventually yields a charge density wave(CDW)state.We further show that,in the CDW phase,the ground-state current density distribution exhibits an intriguing star-of-David pattern,leading to flux density modulation.The orbital fluxes(or current loops)in this system emerge as a result of the subtle interplay between magnetism,lattice geometries,charge order,and spin-orbit coupling(SOC),which can be described by a simple,yet universal,tight-binding theory including a Kane-Mele-type SOC term and a magnetic exchange interaction.We further study the origin of the peculiar step-edge states in FeGe,which sheds light on the topological properties and correlation effects in this new type of kagome antiferromagnetic material. 展开更多
关键词 interaction PHONON ORBITAL
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Extendibility Evaluation of Industrial EUV Source Technologies for kW Average Power and 6.x nm Wavelength Operation 被引量:1
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作者 Akira Endo 《Journal of Modern Physics》 2014年第5期285-295,共11页
Interests in the extendibility are growing after the introduction of the LPP (Laser Produced Plasma) EUV source technology in the semiconductor industry, towards higher average power and shorter wavelength, based on t... Interests in the extendibility are growing after the introduction of the LPP (Laser Produced Plasma) EUV source technology in the semiconductor industry, towards higher average power and shorter wavelength, based on the basic architecture of the established LPP EUV source technology. It is discussed in this article that the power scaling of the 13.5nm wavelength source is essentially possible by a slight increase of the driving laser power, CE (Conversion Efficiency) and EUV collection efficiency by some introduction of novel component technologies. Extension of the EUV wavelength towards BEUV (Beyond EUV), namely 6.x nm is discussed based on the general rule of the UTA (Unresolved Transition Arrays) of high Z ions, and development of multilayer mirrors in this particular wavelength region. Technical difficulties are evaluated for the extension of the LPP source technology by considering the narrower mirror bandwidth and higher melting temperature of the candidate plasma materials. Alternative approach based on the superconducting FEL is evaluated in comparison with the LPP source technology for the future solution. 展开更多
关键词 EUV LPP High Power BEUV FEL Super CONDUCTING ACCELERATOR
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A New Automated Method and Sample Data Flow for Analysis of Volatile Nitrosamines in Human Urine 被引量:1
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作者 James A. Hodgson Tiffany H. Seyler +2 位作者 Ernest McGahee Stephen Arnstein Lanqing Wang 《American Journal of Analytical Chemistry》 2016年第2期165-178,共14页
Volatile nitrosamines (VNAs) are a group of compounds classified as probable (group 2A) and possible (group 2B) carcinogens in humans. Along with certain foods and contaminated drinking water, VNAs are detected at hig... Volatile nitrosamines (VNAs) are a group of compounds classified as probable (group 2A) and possible (group 2B) carcinogens in humans. Along with certain foods and contaminated drinking water, VNAs are detected at high levels in tobacco products and in both mainstream and side-stream smoke. Our laboratory monitors six urinary VNAs—N-nitrosodimethylamine (NDMA), N-nitrosomethylethylamine (NMEA), N-nitrosodiethylamine (NDEA), N-nitrosopiperidine (NPIP), N-nitrosopyrrolidine (NPYR), and N-nitrosomorpholine (NMOR)—using isotope dilution GC-MS/ MS (QQQ) for large population studies such as the National Health and Nutrition Examination Survey (NHANES). In this paper, we report for the first time a new automated sample preparation method to more efficiently quantitate these VNAs. Automation is done using Hamilton STAR<sup>TM</sup> and Caliper Staccato<sup>TM</sup> workstations. This new automated method reduces sample preparation time from 4 hours to 2.5 hours while maintaining precision (inter-run CV < 10%) and accuracy (85% - 111%). More importantly this method increases sample throughput while maintaining a low limit of detection (<10 pg/mL) for all analytes. A streamlined sample data flow was created in parallel to the automated method, in which samples can be tracked from receiving to final LIMs output with minimal human intervention, further minimizing human error in the sample preparation process. This new automated method and the sample data flow are currently applied in bio-monitoring of VNAs in the US non-institutionalized population NHANES 2013-2014 cycle. 展开更多
关键词 Volatile Nitrosamines AUTOMATION Sample Data Flow Gas Chromatography Tandem Mass Spectrometry
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Deep Volatiles as the Key for Energy and Environments of the Four-Dimensional Earth System
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作者 Ho-Kwang Mao Craig M. Schiffries 《Engineering》 SCIE EI 2019年第3期393-394,共2页
Carbon, hydrogen, oxygen, nitrogen, sulfur, and their compounds are volatile components that dominate the thin and fragile atmosphere, hydrosphere, and biosphere on Earth’s habitable surface. However, the vast majori... Carbon, hydrogen, oxygen, nitrogen, sulfur, and their compounds are volatile components that dominate the thin and fragile atmosphere, hydrosphere, and biosphere on Earth’s habitable surface. However, the vast majority of these volatiles are hidden in the deep interior, where the high pressure–temperature conditions drastically and categorically alter the physics and chemistry of the volatiles. Like the bloodstream of an organism, the circulations and interactions of volatiles in the deep Earth modulate climate, resources, energy, natural hazards, and other factors that define the Earth as a unique living and changing planet. 展开更多
关键词 Four-Dimensional EARTH SYSTEM DEEP VOLATILES
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Parrondo's paradox for chaos control and anticontrol of fractional-order systems
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作者 Marius-F Danca Wallace K S Tang 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期507-513,共7页
We present the generalized forms of Parrondo's paradox existing in fractional-order nonlinear systems.The gener-alization is implemented by applying a parameter switching(PS)algorithm to the corresponding initial ... We present the generalized forms of Parrondo's paradox existing in fractional-order nonlinear systems.The gener-alization is implemented by applying a parameter switching(PS)algorithm to the corresponding initial value problems associated with the fractional-order nonlinear systems.The PS algorithm switches a system parameter within a specific set of N≥2 values when solving the system with some numerical integration method.It is proven that any attractor of the concerned system can be approximated numerically.By replacing the words"winning"and"loosing"in the classical Parrondo's paradox with"order"and"chaos",respectively,the PS algorithm leads to the generalized Parrondo's paradox:chaos_(1)+chaos_(2)+…+chaos_(N)=order and order_(1)+order_(2)+…+order_(N)=chaos.Finally,the concept is well demon-strated with the results based on the fractional-order Chen system. 展开更多
关键词 Parrondo's paradox chaos control parameter switching algorithm fractional-order Chen system
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A behavior and physiology-based decision support tool to predict thermal comfort and stress in non-pregnant,mid-gestation,and late-gestation sows
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作者 Betty R.McConn Allan P.Schinckel +4 位作者 Lindsey Robbins Brianna N.Gaskill Angela R.Green‑Miller Donald C.Lay Jr Jay S.Johnson 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第2期814-826,共13页
Background:Although thermal indices have been proposed for swine,none to our knowledge differentiate by reproductive stage or predict thermal comfort using behavioral and physiological data.The study objective was to ... Background:Although thermal indices have been proposed for swine,none to our knowledge differentiate by reproductive stage or predict thermal comfort using behavioral and physiological data.The study objective was to develop a behavior and physiology-based decision support tool to predict thermal comfort and stress in multiparous(3.28±0.81)non-pregnant(n=11),mid-gestation(n=13),and late-gestation(n=12)sows.Results:Regression analyses were performed using PROC MIXED in SAS 9.4 to determine the optimal environmental indicator[dry bulb temperature(TDB)and dew point]of heat stress(HS)in non-pregnant,mid-gestation,and lategestation sows with respiration rate(RR)and body temperature(TB)successively used as the dependent variable in a cubic function.A linear relationship was observed for skin temperature(T_(S))indicating that TDB rather than the sow HS response impacted T_(S)and so T_(S)was excluded from further analyses.Reproductive stage was significant for all analyses(P<0.05).Heat stress thresholds for each reproductive stage were calculated using the inflections points of RR for mild HS and TB for moderate and severe HS.Mild HS inflection points differed for non-pregnant,mid-gestation,and late gestation sows and occurred at 25.5,25.1,and 24.0℃,respectively.Moderate HS inflection points differed for non-pregnant,mid-gestation,and late gestation sows and occurred at 28.1,27.8,and 25.5℃,respectively.Severe HS inflection points were similar for non-pregnant and mid-gestation sows(32.9℃)but differed for late-gestation sows(30.8℃).These data were integrated with previously collected behavioral thermal preference data to estimate the TDB that non-pregnant,mid-gestation,and late-gestation sows found to be cool(TDB<TDB preference range),comfortable(TDB=TDB preference range),and warm(TDB preference range<TDB<mild HS).Conclusions:The results of this study provide valuable information about thermal comfort and thermal stress thresholds in sows at three reproductive stages.The development of a behavior and physiology-based decision support tool to predict thermal comfort and stress in non-pregnant,mid-gestation,and late-gestation sows is expected to provide swine producers with a more accurate means of managing sow environments. 展开更多
关键词 Decision support GESTATION Heat stress Management SOWS Thermal index
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Identification of C9-C11 unsaturated aldehydes as prediction markers of growth and feed intake for non-ruminant animals fed oxidized soybean oil
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作者 Jieyao Yuan Brian J.Kerr +1 位作者 Shelby M.Curry Chi Chen 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2020年第4期1033-1046,共14页
Background: The benefits of using the oxidized oils from rendering and recycling as an economic source of lipids and energy in animal feed always coexist with the concerns that diverse degradation products in these ox... Background: The benefits of using the oxidized oils from rendering and recycling as an economic source of lipids and energy in animal feed always coexist with the concerns that diverse degradation products in these oxidized oils can negatively affect animal health and performance. Therefore, the quality markers that predict growth performance could be useful when feeding oxidized oils to non-ruminants. However, the correlations between growth performance and chemical profiles of oxidized oils have not been well examined. In this study, six thermally oxidized soybean oils(OSOs) with a wide range of quality measures were prepared under different processing temperatures and processing durations, including 45 °C-336 h;67.5 °C-168 h;90 °C-84 h;135 °C-42 h;180 °C-21 h;and225 °C-10.5 h. Broilers and nursery pigs were randomly assigned to diets containing either unheated control soybean oil or one of six OSOs. Animal performance was determined by measuring body weight gain, feed intake,and gain to feed ratio. The chemical profiles of OSOs were first evaluated by common indicative tests, including peroxide value, thiobarbituric acid reactive substances, p-anisidine value, free fatty acids, oxidized fatty acids,unsaponifiable matter, insoluble impurities, and moisture, and then analyzed by the liquid chromatography-mass spectrometry-based chemometric analysis.Results: Among common quality indicators, p-anisidine value(An V), which reflects the level of carbonyl compounds,had the greatest inverse correlation with the growth performance of both broilers and pigs, followed by free fatty acids and oxidized fatty acids. Among the 17 aldehydes identified in OSOs, C9-C11 alkenals, especially 2-decenal and 2-undecenal, had stronger inverse correlations(r <-0.8) with animal performance compared to C5-C8 saturated alkanals,suggesting that chain length and unsaturation level affect the toxicity of aldehydes.Conclusions: As the major lipid oxidation products contributing to the An V, individual C9-C11 unsaturated aldehydes in heavily-oxidized oils could function as effective prediction markers of growth and feed intake in feeding non-ruminants. 展开更多
关键词 ALDEHYDES BROILER Growth performance Pig Thermally oxidized soybean oil
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Development of an in vitro cell model for LPS-and TNFα-induced airway inflammation
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作者 JiaYingJoey,LEE Wai-ShuiFred,WONG Lit-Hsin,LOO 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2015年第S1期56-56,共1页
OBJECTIVE To develop an in vitro airway epithelial cell model suitable for the large-scale studies of compounds that can suppress lipopolysaccharide(LPS)-and tumor necrosis factor alpha(TNFα)-induced airway inflammat... OBJECTIVE To develop an in vitro airway epithelial cell model suitable for the large-scale studies of compounds that can suppress lipopolysaccharide(LPS)-and tumor necrosis factor alpha(TNFα)-induced airway inflammation.METHODS We have optimized the protocols to culture BEAS-2B,a normal human bronchial epithelial cell line,in glass-bottom 384-well microtiter plates.The cells were stimulated with TNFαand LPS from Pseudomonas aeruginosa,a common lunginfection pathogen in cystic fibrosis and chronic obstructive pulmonary disease.We used ELISA to measure the secretion levels of two pro-inflammatory cytokines,interleukin(IL)-6and-8,after 0,4,8,16,24 hof stimulation;and immunofluorescence microscopy to measure the nuclear translocation of RelA,a subunit of the NF-κB complex,after 0,15,30,60,120 min of stimulation.To suppress the inflammatory response,we pre-treated the cells with a specific IκB kinase-2inhibitor,TPCA-1;the main bioactive component of Andrographis paniculata,andrographolide;and DMSO control for 1h.RESULTS We found that individual stimulant(either TNFα10ng·mL-1 or LPS 10μg·mL-1)increased the IL-6and IL-8 secretion levels by^12-17 foldsas compared to DMSO controls after 8h of stimulation.The combined stimulation(10ng·mL-1 TNFαand 10μg·mL-1 LPS)induced even higher IL-6 and -8 levels(~18-21 folds)at the same time points.Importantly,our imaging study shows that the NF-κB activation is early but transient under TNFαstimulation,late but sustained under LPS stimulation,and early and sustained under the combined stimulation.Finally,we also found that TPCA-1 10μmol·L-1 or andrographolide 30μmol·L-1 drastically reduced the IL-6 and -8 levels down to 4.5-9 folds as compared to the controls.CONCLUSIONThe combined TNFαand LPS stimulations induce faster and more sustained inflammatory responses,which can still be suppressed by anti-inflammatory compounds in our cell model.These more comprehensive activations of inflammatory signaling pathways will enable us to study and distinguish the mechanisms of different anti-inflammatory compounds or natural products. 展开更多
关键词 AIRWAY INFLAMMATION ANTI-INFLAMMATORY COMPOUNDS AN
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