期刊文献+
共找到277篇文章
< 1 2 14 >
每页显示 20 50 100
Alkyl dimethyl betaine activates the low-temperature collection capacity of sodium oleate for scheelite
1
作者 Xu Wang Zhengquan Zhang +5 位作者 Yanfang Cui Wei Li Congren Yang Hao Song Wenqing Qin Fen Jiao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期71-80,共10页
The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB... The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB and NaOl was explored by infrared spectroscopy, X-ray photoelectron spectroscopy, surface tension measurement, foam performance test, and flotation reagent size measurement.The flotation tests revealed that the collector mixed with octadecyl dimethyl betaine (ODB) and NaOl in a mass ratio of 4:96 exhibited the highest collection capacity. The combined collector could increase the scheelite recovery by 3.48% at low temperatures of 8–12℃. This is particularly relevant in the Luanchuan area, which has the largest scheelite concentrate output in China. The results confirmed that ODB enhanced the collection capability of NaOl by improving the dispersion and foaming performance. Betaine can be introduced as an additive to NaOl to improve the recovery of scheelite at low temperatures. 展开更多
关键词 SCHEELITE BETAINE low temperature synergistic effect dispersion FOAMABILITY
下载PDF
Psychiatric comorbidities in epilepsy:population co-occurrence,genetic correlations and causal effects
2
作者 Viktor H Ahlqvist Christina Dardani +14 位作者 Paul Madley-Dowd Harriet Forbes Jessica Rast Caichen Zhong Renee M Gardner Christina Dalman Kristen Lyal cRAIG Newschaffer Torbjorn Tomson Michael Lundberg Daniel Berglind Neil M Davies Brian K Lee Cecilia Magnusson Dheeraj Rai 《General Psychiatry》 CSCD 2024年第1期103-111,共9页
Background Psychiatric comorbidities are common in patients with epilepsy.Reasons for the co-occurrence of psychiatric conditions and epilepsy remain poorly understood.Aim We aimed to triangulate the relationship betw... Background Psychiatric comorbidities are common in patients with epilepsy.Reasons for the co-occurrence of psychiatric conditions and epilepsy remain poorly understood.Aim We aimed to triangulate the relationship between epilepsy and psychiatric conditions to determine the extent and possible origins of these conditions.Methods Using nationwide Swedish health registries,we quantified the lifetime prevalence of psychiatric disorders in patients with epilepsy.We then used summarydata from genome-wide association studies to investigate whether the identified observational associations could be attributed to a shared underlying genetic aetiology using cross-trait linkage disequilibrium score regression.Finally,we assessed the potential bidirectional relationships using two-sample Mendelian randomisation.Results In a cohort of 7628495 individuals,we found that almost half of the 94435 individuals diagnosed with epilepsy were also diagnosed with a psychiatric condition in their lifetime(adjusted lifetime prevalence,44.09%;95%confidence interval(Cl)43.78%to 44.39%).We found evidence for a genetic correlation between epilepsy and some neurodevelopmental and psychiatric conditions.For example,we observed a genetic correlation between epilepsy and attention-deficit/hyperactivity disorder(r,=0.18,95%Cl 0.09 to 0.27,p<0.001)—a correlation that was more pronounced in focal epilepsy(r=0.23,95%CI 0.09 to 0.36,p<0.001).Findings from Mendelian randomisation using common genetic variants did not support bidirectional effects between epilepsy and neurodevelopmental or psychiatric conditions.Conclusions Psychiatric comorbidities are common in patients with epilepsy.Genetic correlations may partially explain some comorbidities;however,there is little evidence of a bidirectional relationship between the genetic liability of epilepsy and psychiatric conditions.These findings highlight the need to understand the role of environmental factors or rare genetic variations in the origins of psychiatric comorbidities in epilepsy. 展开更多
关键词 EPILEPSY Psychiat LIFETIME
下载PDF
Pyroelectric Plate with Magnetoelectric Effect
3
作者 Pavel Grinfeld Michael Grinfeld 《Journal of Applied Mathematics and Physics》 2024年第5期1616-1625,共10页
In dynamic problems the electric and magnetic fields are inseparable. At the same time, a multitude of electrostatic and magnetostatic effects permit mutually independent description. This separation appears to be pos... In dynamic problems the electric and magnetic fields are inseparable. At the same time, a multitude of electrostatic and magnetostatic effects permit mutually independent description. This separation appears to be possible and thermodynamically consistent when the bulk energy density depends only on the polarization density or, alternatively, on the magnetization density. However, when the bulk energy density depends simultaneously on the both densities, then, the electrostatic and magnetostatic effects should be studied together. There appear interesting cross-effects;among those are the change of the internal electrostatic field inside a specimen under the influence of the external magnetic fields, and vice versa. Below, in the framework of thermodynamic approach the boundary value problem for magnetoelectric plate is formulated and analyzed. The exact solution is established for the isotropic pyroelectric plate. 展开更多
关键词 Electricity and Magnetism Pyroelectrics and Pyromagnetics Thermodynamics of Electromagnetostatics Exact Solutions Validation and Verification
下载PDF
Multifunctional MXene/C Aerogels for Enhanced Microwave Absorption and Thermal Insulation 被引量:2
4
作者 Fushuo Wu Peiying Hu +7 位作者 Feiyue Hu Zhihua Tian Jingwen Tang Peigen Zhang Long Pan Michel WBarsoum Longzhu Cai ZhengMing Sun 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第11期74-89,共16页
Two-dimensional transition metal carbides and nitrides(MXene)have emerged as promising candidates for microwave absorption(MA)materials.However,they also have some drawbacks,such as poor impedance matching,high self-s... Two-dimensional transition metal carbides and nitrides(MXene)have emerged as promising candidates for microwave absorption(MA)materials.However,they also have some drawbacks,such as poor impedance matching,high self-stacking tendency,and high density.To tackle these challenges,MXene nanosheets were incorporated into polyacrylonitrile(PAN)nanofibers and subsequently assembled into a three-dimensional(3D)network structure through PAN carbonization,yielding MXene/C aerogels.The 3D network effectively extends the path of microcurrent transmission,leading to enhanced conductive loss of electromagnetic(EM)waves.Moreover,the aerogel’s rich pore structure significantly improves the impedance matching while effectively reducing the density of the MXenebased absorbers.EM parameter analysis shows that the MXene/C aerogels exhibit a minimum reflection loss(RL_(min))value of−53.02 dB(f=4.44 GHz,t=3.8 mm),and an effective absorption bandwidth(EAB)of 5.3 GHz(t=2.4 mm,7.44–12.72 GHz).Radar cross-sectional(RCS)simulations were employed to assess the radar stealth effect of the aerogels,revealing that the maximum RCS reduction value of the perfect electric conductor covered by the MXene/C aerogel reaches 12.02 dB m^(2).In addition to the MA performance,the MXene/C aerogel also demonstrates good thermal insulation performance,and a 5-mm-thick aerogel can generate a temperature gradient of over 30℃ at 82℃.This study provides a feasible design approach for creating lightweight,efficient,and multifunctional MXene-based MA materials. 展开更多
关键词 MXene Microwave absorption AEROGEL Radar cross-sectional(RCS)simulation Thermal insulation
下载PDF
Cellular response toβ-amyloid neurotoxicity in Alzheimer's disease and implications in new therapeutics
5
作者 Haolin Zhang Xianghua Li +3 位作者 Xiaoli Wang Jiayu Xu Felice Elefant Juan Wang 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第1期3-9,共7页
β-Amyloid(Aβ)is a specific pathological hallmark of Alzheimer's disease(AD).Because of its neurotoxicity,AD patients exhibit multiple brain dysfunctions.Disease-modifying therapy(DMT)is the central concept in th... β-Amyloid(Aβ)is a specific pathological hallmark of Alzheimer's disease(AD).Because of its neurotoxicity,AD patients exhibit multiple brain dysfunctions.Disease-modifying therapy(DMT)is the central concept in the development of AD thera-peutics today,and most DMT drugs that are currently in clinical trials are anti-Aβdrugs,such as aducanumab and lecanemab.Therefore,understanding Aβ's neurotoxic mechanism is crucial for Aβ-targeted drug development.Despite its total length of only a few dozen amino acids,Aβis incredibly diverse.In addition to the well-known Aβ_(1-42),N-terminally truncated,glutaminyl cyclase(QC)catalyzed,and pyroglutamate-modified Aβ(pEAβ)is also highly amyloidogenic and far more cytotoxic.The extracel-lular monomeric Aβ_(x-42)(x=1-11)initiates the aggregation to form fibrils and plaques and causes many abnormal cellular responses through cell membrane receptors and receptor-coupled signal pathways.These signal cascades further influence many cel-lular metabolism-related processes,such as gene expression,cell cycle,and cell fate,and ultimately cause severe neural cell damage.However,endogenous cellular anti-Aβdefense processes always accompany the Aβ-induced microenvironment alterations.Aβ-cleaving endopeptidases,Aβ-degrading ubiquitin-proteasome system(UPS),and Aβ-engulfing glial cell immune responses are all essential self-defense mechanisms that we can leverage to develop new drugs.This review discusses some of the most recent advances in understanding Aβ-centric AD mechanisms and suggests prospects for promising anti-Aβstrategies. 展开更多
关键词 Alzheimer's disease(AD) astrocytes ENDOPEPTIDASE glutaminyl cyclase(QC) microglia p75 neurotrophin receptor(p75NTR) proteolysis targeting chimeras(PROTACs) β-Amyloid(Aβ)
下载PDF
Biomechanics associated with tibial stress fracture in runners:A systematic review and meta-analysis
6
作者 Clare E.Milner Eric Foch +1 位作者 Joseph M.Gonzales Drew Petersen 《Journal of Sport and Health Science》 SCIE CSCD 2023年第3期333-342,共10页
Background:Tibial stress fracture(TSF)is an overuse running injury with a long recovery period.While many running studies refer to biomechanical risk factors for TSF,only a few have compared biomechanics in runners wi... Background:Tibial stress fracture(TSF)is an overuse running injury with a long recovery period.While many running studies refer to biomechanical risk factors for TSF,only a few have compared biomechanics in runners with TSF to controls.The aim of this systematic review and meta-analysis was to evaluate biomechanics in runners with TSF compared to controls.Methods:Electronic databases PubMed,Web of Science,SPORTDiscus,Scopus,Cochrane,and CINAHL were searched.Risk of bias was assessed and meta-analysis conducted for variables reported in 3 or more studies.Results:The search retrieved 359 unique records,but only the 14 that compared runners with TSF to controls were included in the review.Most studies were retrospective,2 were prospective,and most had a small sample size(5-30 per group).Many variables were not significantly different between groups.Meta-analysis of peak impact,active,and braking ground reaction forces found no significant differences between groups.Individual studies found larger tibial peak anterior tensile stress,peak posterior compressive stress,peak axial acceleration,peak rearfoot eversion,and hip adduction in the TSF group.Conclusion:Meta-analysis indicated that discrete ground reaction force variables were not statistically significantly different in runners with TSF compared to controls.In individual included studies,many biomechanical variables were not statistically significantly different between groups.However,many were reported by only a single study,and sample sizes were small.We encourage additional studies with larger sample sizes of runners with TSF and controls and adequate statistical power to confirm or refute these findings. 展开更多
关键词 Bone stress injury GAIT KINEMATICS Kinetics Tibial acceleration
下载PDF
In situ TEM observations and molecular dynamics simulations of deformation defect activities in Mg via nanoindentation
7
作者 Yi-Cheng Lai Yubin Ying +3 位作者 Digvijay Yadav Jose Guerrero Yong-Jie Hu Kelvin Y.Xie 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第12期4513-4524,共12页
In this work, we performed in situ nanoindentation in TEM to capture the real-time dislocation and twinning activities in pure Mg during loading and unloading. We demonstrated that the screw component of dislocations ... In this work, we performed in situ nanoindentation in TEM to capture the real-time dislocation and twinning activities in pure Mg during loading and unloading. We demonstrated that the screw component of dislocations glides continuously, while the edge components rapidly become sessile during loading. The twin tip propagation is intermittent, whereas the twin boundary migration is more continuous. During unloading, we observed the elastic strain relaxation causes both dislocation retraction and detwinning. Moreover,we note that the plastic zone comprised of dislocations in Mg is well-defined, which contrasts with the diffused plastic zones observed in face-centered cubic metals under the nanoindentation impressions. Additionally, molecular dynamics simulations were performed to study the formation and evolution of deformation-induced crystallographic defects at the early stages of indentation. We observed that,in addition to dislocations, the I1stacking fault bounded with a <1/2c+p> Frank loop can be generated from the plastic zone ahead of the indenter, and potentially serve as a nucleation source for abundant dislocations observed experimentally. These new findings are anticipated to provide new knowledge on the deformation mechanisms of Mg, which are difficult to obtain through conventional ex situ approaches. These observations may serve as a baseline for simulation work that investigate the dynamics of dislocation slip and twinning in Mg and alloys. 展开更多
关键词 In situ TEM Molecular dynamics simulation DISLOCATION TWINNING Mg NANOINDENTATION
下载PDF
Free-Standing α-MoO_(3)/Ti_(3)C_(2) MXene Hybrid Electrode in Water-in-Salt Electrolytes
8
作者 Mohit Saraf Christopher E.Shuck +5 位作者 Nazgol Norouzi Kyle Matthews Alex Inman Teng Zhang Ekaterina Pomerantseva Yury Gogotsi 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期6-14,共9页
While transition-metal oxides such as α-MoO_(3)provide high capacity,their use is limited by modest electronic conductivity and electrochemical instability in aqueous electrolytes.Two-dimensional(2D)MXenes,offer meta... While transition-metal oxides such as α-MoO_(3)provide high capacity,their use is limited by modest electronic conductivity and electrochemical instability in aqueous electrolytes.Two-dimensional(2D)MXenes,offer metallic conductivity,but their capacitance is limited in aqueous electrolytes.Insertion of partially solvated cations into Ti_(3)C_(2)MXene from lithium-based water-in-salt(WIS)electrolytes enables charge storage at positive potentials,allowing a wider potential window and higher capacitance.Herein,we demonstrate that α-MoO_(3)/Ti_(3)C_(2)hybrids combine the high capacity of α-MoO_(3)and conductivity of Ti_(3)C_(2)in WIS(19.8 m LiCI)electrolyte in a wide1.8 V voltage window.Cyclic voltammograms reveal multiple redox peaks from α-MoO_(3)in addition to the well-separated peaks of Ti_(3)C_(2)in the hybrid electrode.This leads to a higher specific charge and a higher rate capability compared to a carbon and binder containing α-MoO_(3)electrode.These results demonstrate that the addition of MXene to less conductive oxides eliminates the need for conductive carbon additives and binders,leads to a larger amount of charge stored,and increases redox capacity at higher rates.In addition,MXene encapsulated α-MoO_(3)showed improved electrochemical stability,which was attributed to the suppressed dissolution of α-MoO_(3).The work suggests that oxide/MXene hybrids are promising for energy storage. 展开更多
关键词 free-standing electrode Ti_(3)C_(2)MXene water-in-salt electrolytes α-MoO_(3)nanobelts
下载PDF
Pharmacoepidemiologic study of association between apparent treatment resistant hypertension, cardiovascular disease and interaction effect by sex and age
9
作者 Julianne Theresa Nelson Longjian Liu 《World Journal of Cardiology》 2023年第5期262-272,共11页
BACKGROUND A limited number of studies have been conducted to test the magnitudes of the association between apparent treatment resistant hypertension(aTRH)and risk of cardiovascular disease(CVD).AIM To investigate th... BACKGROUND A limited number of studies have been conducted to test the magnitudes of the association between apparent treatment resistant hypertension(aTRH)and risk of cardiovascular disease(CVD).AIM To investigate the association between aTRH and risk of CVD and examine whether sex and age modify this association.METHODS We applied an observational analysis study design using data from the United States Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial(ALLHAT).ALLHAT recruited participants(n=25516)from 625 primary care settings throughout the United States,Canada,Puerto Rico,and United States Virgin Islands,aged 55 and older with hypertension and at least one additional risk factor for heart disease.aTRH was assessed from the year 2 visit.CVD event was defined as one of the following from the year 2 follow-up visit:Fatal or non-fatal myocardial infarction,coronary revascularization,angina,stroke,heart failure,or peripheral artery disease.Cox proportional hazards regression was used to examine the effect of aTRH on CVD risk.Potential modifications of sex and age on this association were examined on the multiplicative scale by interaction term and additive scale by joint effects and relative excess risk for interaction.RESULTS Of the total study participants(n=25516),5030 experienced a CVD event during a mean of 4.7 years follow-up.aTRH was associated with a 30%increase in risk of CVD compared to non-aTRH[hazards ratio(HR)=1.3,95%CI:1.19-1.42].Sex and age modified this relationship on both multiplicative and additive scales independently.Stratified by sex,aTRH was associated with a 64%increase in risk of CVD(HR=1.64,95%CI:1.43–1.88)in women,and a 13%increase in risk of CVD(HR=1.13,95%CI:1.01–1.27)in men.Stratified by age,aTRH had a stronger impact on the risk of CVD in participants aged<65(HR=1.53,95%CI:1.32–1.77)than it did in those aged≥65(HR=1.18,95%CI:1.05–1.32).Significant two-way interactions of sex and aTRH,and age and aTRH on risk of CVD were observed(P<0.05).The observed joint effect of aTRH and ages≥65 years(HR=1.85,95%CI:1.22–2.48)in males was less than what was expected for both additive and multiplicative models(HR=4.10,95%CI:3.63–4.57 and 4.88,95%CI:3.66–6.31),although three-way interaction of sex,age,and aTRH on the risk of CVD and coronary heart disease did not reach a statistical significance(P>0.05).CONCLUSION aTRH was significantly associated with an increased risk of CVD and this association was modified by both sex and age.Further studies are warranted to test these mechanisms. 展开更多
关键词 Apparent treatment resistant hypertension Cardiovascular disease outcomes Chronic kidney disease SEX Age
下载PDF
Fidgetin interacting with microtubule end binding protein EB3 affects axonal regrowth in spinal cord injury
10
作者 Chao Ma Junpei Wang +8 位作者 Qifeng Tu Weijuan Bo Zunlu Hu Run Zhuo Ronghua Wu Zhangji Dong Liang Qiang Yan Liu Mei Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第12期2727-2732,共6页
Fidgetin,a microtubule-severing enzyme,regulates neurite outgrowth,axonal regeneration,and cell migration by trimming off the labile domain of microtubule polymers.Because maintenance of the microtubule labile domain ... Fidgetin,a microtubule-severing enzyme,regulates neurite outgrowth,axonal regeneration,and cell migration by trimming off the labile domain of microtubule polymers.Because maintenance of the microtubule labile domain is essential for axon initiation,elongation,and navigation,it is of interest to determine whether augmenting the microtubule labile domain via depletion of fidgetin serves as a therapeutic approach to promote axonal regrowth in spinal cord injury.In this study,we constructed rat models of spinal cord injury and sciatic nerve injury.Compared with spinal cord injury,we found that expression level of tyrosinated microtubules in the labile portion of microtubules continuously increased,whereas fidgetin decreased after peripheral nerve injury.Depletion of fidgetin enhanced axon regeneration after spinal cord injury,whereas expression level of end binding protein 3(EB3)markedly increased.Next,we performed RNA interference to knockdown EB3 or fidgetin.We found that deletion of EB3 did not change fidgetin expression.Conversely,deletion of fidgetin markedly increased expression of tyrosinated microtubules and EB3.Deletion of fidgetin increased the amount of EB3 at the end of neurites and thereby increased the level of tyrosinated microtubules.Finally,we deleted EB3 and overexpressed fidgetin.We found that fidgetin trimmed tyrosinated tubulins by interacting with EB3.When fidgetin was deleted,the labile portion of microtubules was elongated,and as a result the length of axons and number of axon branches were increased.These findings suggest that fidgetin can be used as a novel therapeutic target to promote axonal regeneration after spinal cord injury.Furthermore,they reveal an innovative mechanism by which fidgetin preferentially severs labile microtubules. 展开更多
关键词 acetylated microtubules axon regeneration axonal branching axonal regrowth end binding protein 3 fidgetin microtubule dynamics sciatic nerve injury spinal cord injury tyrosinated microtubules
下载PDF
A Vector Tensor Calculus Description of a Euclidean Space
11
作者 Pavel Grinfeld 《Journal of Applied Mathematics and Physics》 2023年第3期705-720,共16页
We present a tensor description of Euclidean spaces that emphasizes the use of geometric vectors which leads to greater geometric insight and a higher degree of organization in analytical expressions. We demonstrate t... We present a tensor description of Euclidean spaces that emphasizes the use of geometric vectors which leads to greater geometric insight and a higher degree of organization in analytical expressions. We demonstrate the effectiveness of the approach by proving a number of integral identities with vector integrands. The presented approach may be aptly described as absolute vector calculus or as vector tensor calculus. 展开更多
关键词 Tensor Calculus Differential Geometry Embedded Surfaces and Curves Scalar Curvature Gaussian Curvature
下载PDF
Morphological Instability of Phase Interface between Pyroelectric Domains
12
作者 Michael Grinfeld Pavel Grinfeld 《Journal of Applied Mathematics and Physics》 2023年第2期541-554,共14页
The Gibbs-like variational methodology is applied to the heterogeneous systems with rigid pyroelectric or pyromagnetic domains. The processes of depolarization/demagnetization are taken into account by assuming the sp... The Gibbs-like variational methodology is applied to the heterogeneous systems with rigid pyroelectric or pyromagnetic domains. The processes of depolarization/demagnetization are taken into account by assuming the spatial mobility of the interfaces. The simplest configuration of flat interface separating rigid pyroelectric half-spaces permits explicit analysis of morphological stability. 展开更多
关键词 Pyro- and Ferroelectricity Pyro- and Ferromagnetism Heterogeneous System Variational Principles Cardinal Tensors Morphological Instabilities
下载PDF
Implication of Oxidative Stress and Antioxidant Defence Systems in Symptomatic and Asymptomatic Plasmodium falciparum Malaria Infection among Children Aged 1 to 15 Years in the Mount Cameroon Area
13
作者 Tambong Ako Ojongnkpot David Denis Sofeu-Feugaing +2 位作者 Vanessa Tita Jugha Germain Sotoing Taiwe Helen Kuokuo Kimbi 《Journal of Biosciences and Medicines》 CAS 2023年第2期124-145,共22页
It is known that the pathogenicity of Plasmodium induces the breakdown of haemoglobin, which leads to the induction of oxidative stress. This study aimed to identify the possible effects of oxidative stress and antiox... It is known that the pathogenicity of Plasmodium induces the breakdown of haemoglobin, which leads to the induction of oxidative stress. This study aimed to identify the possible effects of oxidative stress and antioxidant defence systems in symptomatic and asymptomatic Plasmodium falciparum malaria infection in children (1 - 15 years old) in the Mount Cameroon vicinity. This cross-sectional study involved blood samples collected from 473 children and examined for malaria parasitaemia. Full blood counts were performed using an automated haemoanalyser. Serum oxidative stress status (malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD) and vitamin C (Vit C)) were each determined by colorimetric enzymatic assays. The prevalence of malaria parasite infection was 32.1% among the participants. Out of that, 62.5% of patients with parasitaemia were symptomatic. Anaemia prevalence increased significantly with parasite density. MDA levels were significantly higher in patients with malaria symptoms than in those without symptoms. A significant and positive correlation was detected between MDA (r = 0.831, P < 0.05), NO (r = 0.779, P < 0.05), and malaria parasite density while, a significant and negative relationship occurred between parasite density and GSH (r = ?0.763, P < 0.05) and Vit C (r = ?0.826, P < 0.05) levels, SOD (r = ?0.621, P < 0.05) and CAT (r = ?0.817, P < 0.05) activities. The SOD activity and GSH level significantly decreased (P < 0.05) with an increase in the MDA levels. These findings showed that MDA and nitric oxide levels increased both in malaria participants with or without symptoms. A similar decrease in the antioxidant defence system was observed in both symptomatic and asymptomatic patients. Therefore, there is a need to develop public health policies that encourage routine diagnosis and treatment of malaria in seemingly healthy people (asymptomatic cases), and this will play an essential role in controlling malaria in tropical countries. 展开更多
关键词 MALARIA ASYMPTOMATIC SYMPTOMATIC Oxidative Stress Antioxidant Defence System
下载PDF
Deformable Permanent Ferroelectric or Ferromagnetic Media
14
作者 Michael Grinfeld Pavel Grinfeld 《Journal of Applied Mathematics and Physics》 2023年第10期3061-3074,共14页
In the framework of continuum mechanics, one of possible consistent definitions of deformable permanent magnets is introduced and explored. Similar model can be used for ferroelectric substances. Based on the suggeste... In the framework of continuum mechanics, one of possible consistent definitions of deformable permanent magnets is introduced and explored. Similar model can be used for ferroelectric substances. Based on the suggested definition, we establish the key kinematic relationship for the deformable permanent magnet and suggest the simplest master system, allowing to analyze behavior of such substances. 展开更多
关键词 Ferroelectric and Ferromagnetic Media Thermodynamic Consistency The Aleph Tensor Boundary Value Problems of Electro- and Magnetostatics and Quasi-Statics
下载PDF
MXene ink hosting zinc anode for high performance aqueous zinc metal batteries
15
作者 Jae Min Park Milan Jana +9 位作者 Sang Ha Baek Taehun Kang Peixun Xiong Jeong Hee Park Jun Soo Kim Ali Shayesteh Zeraati Mikhail Shekhirev Paul V.Braun Yury Gogotsi Ho Seok Park 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期187-194,I0005,共9页
Despite the safety,low cost,and high theoretical capacity(820 mA h g^(-1))of Zn metal anodes,the practical application of aqueous Zn metal batteries remains a critical challenge due to the Zn dendrite growth,corrosion... Despite the safety,low cost,and high theoretical capacity(820 mA h g^(-1))of Zn metal anodes,the practical application of aqueous Zn metal batteries remains a critical challenge due to the Zn dendrite growth,corrosion,and hydrogen evolution reaction.Herein,we demonstrate the MXene ink hosting Zn metal anodes(MX@Zn)for high-performance and patternable Zn metal full batteries.The as-designed MX@Zn electrode is more facile and reversible than bare Zn and CC@Zn,as verified by better cyclic stability and lower overpotentials of symmetric cells with the plating capacity of 0.05 mA h cm^(-2)at 0.1 m A cm^(-2)and of 1 m A h cm^(-2)at 1 m A cm^(-2).The MX@Zn|MnO_(2)full cells deliver a high specific capacity of 281.9 m A h g^(-1),91.5%of the theoretical capacity,achieving 50%capacity retention from 60 mA g^(-1)to 300 mA g^(-1)and 79.7%of initial capacity after 200 cycles.Moreover,the patterned devices based on the MX@Zn electrode achieve high energy and power densities of 348.57 Wh kg^(-1)and 1556 W kg^(-1),respectively,along with a capacity retention of 64%and Coulombic efficiency of 99%over 500 cycles.The high performance of MX@Zn is attributed to the high electrical conductivity and hydrophilicity of MXene and rapid ion diffusion through the 3D interconnected porous channels. 展开更多
关键词 MXene ink Zinc anode Metal batteries PATTERNING ELECTRODEPOSITION
下载PDF
A Validated Model for the Imaging Diagnosis of Cystic Lung Disease
16
作者 Wallace T. Miller Karen C. Patterson +22 位作者 Shweta Sood James E. Schmitt Arshad A. Wani Robert Borden Maya Galperin-Aisenberg Mary K. Porteus Michelle L. Hershman Michael Hewitt Jennifer Levy Victor D. Babatunde Tetiana Glushko Timothy J. Niesen Sergey Leshchinskiy Karine Sahakyan Keyur Desai Jennifer A. Gillman Sandeep Reddy Michael Shriver Nathaniel B. Linna Abass M. Noor Aysenur Buz Matthew E. Biron Scott Simpson 《Open Journal of Radiology》 2023年第1期42-57,共16页
Rationale and Objectives: Cystic lung disease may be accurately diagnosed by imaging interpretation of specialist radiologists, without other information. We hypothesized that with minimal training non-specialists cou... Rationale and Objectives: Cystic lung disease may be accurately diagnosed by imaging interpretation of specialist radiologists, without other information. We hypothesized that with minimal training non-specialists could perform similarly to specialist physicians in the diagnosis of cystic lung disease. Methods: 72 cystic lung disease cases and 25 cystic lung disease mimics were obtained from three sources: 1) a prospective acquired diffuse lung disease registry, 2) a retrospective search of medical records and 3) teaching files. Cases were anonymized, randomized and interpreted by 7 diffuse lung disease specialists and 15 non-specialist radiologists and pulmonologists. Clinical information other than age and sex was not provided. Prior to interpretation, non-specialists viewed a short PDF training document explaining cystic lung disease interpretation. Results: Correct first choice diagnosis of 85%-88% may be achieved by high-performing specialist readers and 71%-80% by non-specialists and lower-performing specialists, with mean accuracies in the diagnosis of LAM (91%, p Conclusion: With specific but limited training, non-specialist physicians can diagnose cystic lung diseases from CT appearance alone with similar accuracy to specialists, correctly identifying approximately 75% of cases. 展开更多
关键词 LYMPHANGIOLEIOMYOMATOSIS HISTIOCYTOSIS Langerhans-Cell Idiopathic Interstitial Pneumonias Birt-Hogg-Dube Syndrome Lung Diseases INTERSTITIAL DIAGNOSES Differential
下载PDF
菲在土壤/沉积物上的吸附-解吸过程及滞后现象的研究 被引量:59
17
作者 梁重山 党志 +1 位作者 刘丛强 黄伟林 《土壤学报》 CAS CSCD 北大核心 2004年第3期329-335,共7页
实验研究了菲在土壤 /沉积物上的吸附 解吸过程。CHL土壤和HFH沉积物中有机质的固相13 CCPMASNMR谱图很相似 ,表明样品中有机质的组成差异不大 ;菲在土壤 /沉积物上的吸附过程表现出明显的非线性 ;线性模型不适合拟合菲的吸附等温线 ,F... 实验研究了菲在土壤 /沉积物上的吸附 解吸过程。CHL土壤和HFH沉积物中有机质的固相13 CCPMASNMR谱图很相似 ,表明样品中有机质的组成差异不大 ;菲在土壤 /沉积物上的吸附过程表现出明显的非线性 ;线性模型不适合拟合菲的吸附等温线 ,Freundlich模型和双区位反应模型 (DRDM)较好地拟合了菲的吸附等温线 ,其中DRDM模型还清楚地反映菲在低浓度和高浓度下不同的吸附方式 ;另外 ,研究表明菲在土壤 /沉积物上的解吸过程中存在明显的滞后现象 ,这可能和土壤 /沉积物有机质的异质性和土壤胶团微小孔隙的存在有关。 展开更多
关键词 有机物污染 土壤/沉积物 吸附-解吸过程 滞后现象 线性模型 FREUNDLICH模型 双区位反应模型
下载PDF
脱细胞真皮基质的改建及其作为软骨细胞移植载体在兔软骨缺损修复中的应用 被引量:6
18
作者 江健 孙磊 +3 位作者 冯华 陈磊 陶剑锋 Peter I.Lelkes 《中国运动医学杂志》 CAS CSCD 北大核心 2008年第4期412-415,共4页
目的:探讨脱细胞真皮(acellular dermal matrix,ADM)经改建后作为软骨细胞移植载体的可行性。方法:取新生小牛背部真皮组织,分别用自制脱细胞剂和表面活性剂对其进行脱细胞处理后,观察得出自制脱细胞剂脱细胞的效果良好,但脱细胞后的胶... 目的:探讨脱细胞真皮(acellular dermal matrix,ADM)经改建后作为软骨细胞移植载体的可行性。方法:取新生小牛背部真皮组织,分别用自制脱细胞剂和表面活性剂对其进行脱细胞处理后,观察得出自制脱细胞剂脱细胞的效果良好,但脱细胞后的胶原纤维结构需要改建;将自制脱细胞剂脱细胞后的真皮组织分别用按一定浓度配比的消化液和胃蛋白酶消化,发现经配比消化液改建后的胶原纤维表面光滑、孔隙均匀,符合软骨细胞移植载体的要求;比较戊二醛和水溶性交联剂对改建后脱细胞真皮基质的交联效果,可见水溶性交联剂交联后的ADM载体植入大鼠皮下后,其生物相容性良好;用生长因子对改建和交联后的ADM进行纤维表面修饰,然后接种乳兔软骨细胞,观察细胞粘附及生长情况;最后将接种有兔自体软骨细胞的ADM植入兔胫骨软骨缺损部位,术后定期取材观察修复效果。结果:(1)经戊二醛交联后的ADM植入大鼠皮下后有强烈的炎症反应,并有组织出血坏死;而经水溶性交联剂交联的ADM的组织相容性较好。(2)在植入接种有自体软骨细胞的ADM24周后,大白兔胫骨的软骨缺损修复完好,附和的细胞能够存活且增殖,ADM本身基本降解。结论:经脱细胞、纤维改建、交联及生长因子修饰的ADM孔隙均匀,组织相容性好,适于细胞粘附及长期生长。ADM胶原支架在兔体内可基本降解,未见排异反应,移植24周后骨缺损修复。 展开更多
关键词 脱细胞真皮 组织工程 软骨细胞 软骨修复
下载PDF
氨基封端苯胺五聚体的合成及紫外光谱研究 被引量:4
19
作者 陈梁 于有海 +3 位作者 毛华平 卢晓峰 张万金 危岩 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2004年第9期1768-1770,共3页
Compound B was synthesized through oxidative coupling reaction of p-phenylene-diamine and compound A(acetylamino-capped aniline dimer). This synthetic route protected the N-phenyl-1,4-phenylenediamine from further rea... Compound B was synthesized through oxidative coupling reaction of p-phenylene-diamine and compound A(acetylamino-capped aniline dimer). This synthetic route protected the N-phenyl-1,4-phenylenediamine from further reaction. The pentamer was synthesized by the hydrolysis of compound B(acetylamino-capped aniline pentamer) and was characterized by IR, elemental analysis and MALDI-TOF-MS. The chemical oxidation process of the pentamer was studied by UV-Vis spectra. It was found the pentamer was oxidized to its EB form and then to the pernigraniline oxidation state. 展开更多
关键词 苯胺齐聚物 氨基封端苯胺五聚体 紫外可见光谱
下载PDF
兔软骨细胞与骨髓基质细胞的平面共培养:两者培养比例筛选 被引量:4
20
作者 孙磊 綦惠 +6 位作者 陈磊 陈海燕 江健 陶剑锋 杰永生 高新生 Peter I.Lelkes 《中国组织工程研究与临床康复》 CAS CSCD 北大核心 2010年第27期4955-4959,共5页
背景:骨髓基质细胞一定条件下可以分化为软骨细胞,但目前还缺少将软骨与骨髓基质细胞平面共培养的深入探讨。目的:拟明确骨髓基质细胞与软骨细胞共培养时比例的选择、细胞增殖活性、软骨特异性蛋白表达的规律,用于细胞移植的最佳时间... 背景:骨髓基质细胞一定条件下可以分化为软骨细胞,但目前还缺少将软骨与骨髓基质细胞平面共培养的深入探讨。目的:拟明确骨髓基质细胞与软骨细胞共培养时比例的选择、细胞增殖活性、软骨特异性蛋白表达的规律,用于细胞移植的最佳时间和传代次数。方法:软骨细胞与骨髓基质细胞的分离培养,传代后分为5组:单纯软骨细胞组;共培养组,软骨细胞与骨髓基质细胞7:3,5:5,3:7组;以及单纯骨髓基质细胞组。传代至第4代(G4),倒置相差显微镜观察各组细胞在不同传代时期的细胞形态,MTT实验检测细胞增殖活性,甲苯胺蓝与阿利新蓝染色,细胞免疫化学法检测Ⅱ型胶原的表达。结果与结论:共培养各组在各个时期细胞表型正常。G1-G3代细胞增殖活跃,G4代细胞增殖能力下降。共培养各组甲苯胺蓝与阿利新蓝染色以及Ⅱ型胶原表达在G2和G3代均较高。综合各指标认为,以软骨细胞与骨髓基质细胞的比例为5:5,3:7组为最佳。软骨细胞与骨髓基质细胞平面共培养,保持了软骨细胞的形态和蛋白表达特性,如进行细胞移植,选取软骨细胞与骨髓基质细胞5:5或3:7的比例为最佳。 展开更多
关键词 软骨细胞 骨髓基质细胞 共培养 蛋白聚糖 Ⅱ型胶原
下载PDF
上一页 1 2 14 下一页 到第
使用帮助 返回顶部