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Effects of neural stem cell transplantation on the motor function of rats with contusion spinal cord injuries:a meta-analysis 预览
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作者 Kai Qian Tuo-Ye Xu +7 位作者 Xi Wang Tao Ma Kai-Xin Zhang Kun Yang Teng-Da Qian Jing Shi Li-Xin Li Zheng Wang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第4期748-758,共11页
Objective:To judge the efficacies of neural stem cell(NSC)transplantation on functional recovery following contusion spinal cord injuries(SCIs).Data sources:Studies in which NSCs were transplanted into a clinically re... Objective:To judge the efficacies of neural stem cell(NSC)transplantation on functional recovery following contusion spinal cord injuries(SCIs).Data sources:Studies in which NSCs were transplanted into a clinically relevant,standardized rat model of contusion SCI were identified by searching the PubMed,Embase and Cochrane databases,and the extracted data were analyzed by Stata 14.0.Data selection:Inclusion criteria were that NSCs were used in in vivo animal studies to treat contusion SCIs and that behavioral assessment of locomotor functional recovery was performed using the Basso,Beattie,and Bresnahan lo-comotor rating scale.Exclusion criteria included a follow-up of less than 4 weeks and the lack of control groups.Outcome measures:The restoration of motor function was assessed by the Basso,Beattie,and Bresnahan locomotor rating scale.Results:We identified 1756 non-duplicated papers by searching the aforementioned electronic databases,and 30 full-text articles met the inclusion criteria.A total of 37 studies reported in the 30 articles were included in the meta-analysis.The meta-analysis results showed that transplanted NSCs could improve the motor function recovery of rats following contusion SCIs,to a moderate extent(pooled standardized mean difference(SMD)=0.73;95%confidence interval(CI):0.47–1.00;P<0.001).NSCs obtained from different donor species(rat:SMD=0.74;95%CI:0.36–1.13;human:SMD=0.78;95%CI:0.31–1.25),at different donor ages(fetal:SMD=0.67;95%CI:0.43–0.92;adult:SMD=0.86;95%CI:0.50–1.22)and from different origins(brain-derived:SMD=0.59;95%CI:0.27–0.91;spinal cord-derived:SMD=0.51;95%CI:0.22–0.79)had similar efficacies on improved functional recovery;however,adult induced pluripotent stem cell-derived NSCs showed no significant efficacies.Furthermore,the use of higher doses of transplanted NSCs or the administration of immunosuppressive agents did not promote better locomotor function recovery(SMD=0.45;95%CI:0.21–0.70).However,shorter periods between the contusion induction and the NSC tr 展开更多
关键词 Basso Beattie and Bresnahan locomotor rating scale CELL TRANSPLANTATION META-ANALYSIS motor functional recovery NEURAL regeneration NEURAL stem CELL NEURAL stem CELL TRANSPLANTATION rat model SPINAL CONTUSION SPINAL cord injury
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Neurological recovery and antioxidant effects of resveratrol in rats with spinal cord injury:a meta-analysis 预览
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作者 Bao-Ping Xu Min Yao +4 位作者 Zhen-Jun Li Zi-Rui Tian Jie Ye Yong-Jun Wang Xue-Jun Cui 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第3期482-490,共9页
Objective:To critically assess the neurological recovery and antioxidant effects of resveratrol in rat models of spinal cord injury.Data sources:Using“spinal cord injury”,“resveratrol”and“animal experiment”as th... Objective:To critically assess the neurological recovery and antioxidant effects of resveratrol in rat models of spinal cord injury.Data sources:Using“spinal cord injury”,“resveratrol”and“animal experiment”as the main search terms,all studies on the treatment of spinal cord injury in rats by resveratrol were searched for in PubMed,EMBASE,MEDLINE,Web of Science,Science Direct,China National Knowledge Infrastructure,Wanfang,VIP,and SinoMed databases by computer.The search was conducted from their inception date to April 2017.No language restriction was used in the literature search.Data selection:The methodological quality of each study was assessed by the initial Stroke Therapy Academic Industry Roundtable recommendations.Two reviewers independently selected studies according to the title,abstract and full text.The risk of bias in the included studies was also evaluated.Meta-analyses were performed with Review Manager 5.3 software.Outcome measures:Neurological function was assessed by the Basso,Beattie,and Bresnahan scale score,inclined plane score and Gale’s motor function score.Molecular-biological analysis of antioxidative effects was conducted to determine superoxide dismutase levels,malondialdehyde levels,nitric oxide synthase activity,nitric oxide levels,xanthine oxidase and glutathione levels in spinal cord tissues.Results:The methodological quality of the 12 included studies was poor.The results of meta-analysis showed that compared with the control group,resveratrol significantly increased the Basso,Beattie,and Bresnahan scale scores after spinal cord injury(n=300,mean difference(MD)=3.85,95%confidence interval(CI)[2.10,5.59],P<0.0001).Compared with the control group,superoxide dismutase levels were significantly elevated(n=138,standardized mean difference(SMD)=5.22,95%CI[2.98,7.45],P<0.00001),but malondialdehyde levels were significantly diminished(n=84,SMD=–3.64,95%CI[–5.84,–1.43],P=0.001)in the spinal cord of the resveratrol treatment group.Conclusions:Resveratrol promoted neurologi 展开更多
关键词 ANTIOXIDATION META-ANALYSIS NEUROLOGICAL recovery PHARMACOTHERAPY RATS RESVERATROL spinal cord injury systematic review
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Three-dimensional bioprinting collagen/silk fibroin scaffold combined with neural stem cells promotes nerve regeneration after spinal cord injury 预览
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作者 Ji-Peng Jiang Xiao-Yin Liu +9 位作者 Fei Zhao Xiang Zhu Xiao-Yin Li Xue-Gang Niu Zi-Tong Yao Chen Dai Hui-You Xu Ke Ma Xu-Yi Chen Sai Zhang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第5期959-968,共10页
Many studies have shown that bio-scaffolds have important value for promoting axonal regeneration of injured spinal cord.Indeed,cell transplantation and bio-scaffold implantation are considered to be effective methods... Many studies have shown that bio-scaffolds have important value for promoting axonal regeneration of injured spinal cord.Indeed,cell transplantation and bio-scaffold implantation are considered to be effective methods for neural regeneration.This study was designed to fabricate a type of three-dimensional collagen/silk fibroin scaffold (3D-CF) with cavities that simulate the anatomy of normal spinal cord.This scaffold allows cell growth in vitro and in vivo.To observe the effects of combined transplantation of neural stem cells (NSCs) and 3D-CF on the repair of spinal cord injury.Forty Sprague-Dawley rats were divided into four groups: sham (only laminectomy was performed),spinal cord injury (transection injury of T10 spinal cord without any transplantation),3D-CF (3D scaffold was transplanted into the local injured cavity),and 3D-CF + NSCs (3D scaffold co-cultured with NSCs was transplanted into the local injured cavity.Neuroelectrophysiology,imaging,hematoxylin-eosin staining,argentaffin staining,immunofluorescence staining,and western blot assay were performed.Apart from the sham group,neurological scores were significantly higher in the 3D-CF + NSCs group compared with other groups.Moreover,latency of the 3D-CF + NSCs group was significantly reduced,while the amplitude was significantly increased in motor evoked potential tests.The results of magnetic resonance imaging and diffusion tensor imaging showed that both spinal cord continuity and the filling of injury cavity were the best in the 3D-CF + NSCs group.Moreover,regenerative axons were abundant and glial scarring was reduced in the 3D-CF + NSCs group compared with other groups.These results confirm that implantation of 3D-CF combined with NSCs can promote the repair of injured spinal cord.This study was approved by the Institutional Animal Care and Use Committee of People’s Armed Police Force Medical Center in 2017 (approval No.2017-0007.2). 展开更多
关键词 3D BIOPRINTING COLLAGEN diffusion tensor IMAGING functional recovery magnetic resonance IMAGING nerve REGENERATION NEURAL REGENERATION NEURAL stem cell SCAFFOLD silk fibroin spinal cord injury
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Transdermal delivery of 4-aminopyridine accelerates motor functional recovery and improves nerve morphology following sciatic nerve crush injury in mice 预览
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作者 Andrew RClark Chia George Hsu +2 位作者 M A Hassan Talukder Mark Noble John CElfar 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第1期136-144,共9页
Oral 4-aminopyridine(4-AP)is clinically used for symptomatic relief in multiple sclerosis and we recently demonstrated that systemic 4-AP had previously unknown clinically-relevant effects after traumatic peripheral n... Oral 4-aminopyridine(4-AP)is clinically used for symptomatic relief in multiple sclerosis and we recently demonstrated that systemic 4-AP had previously unknown clinically-relevant effects after traumatic peripheral nerve injury including the promotion of re-myelination,improvement of nerve conductivity,and acceleration of functional recovery.We hypothesized that,instead of oral or injection administration,transdermal 4-AP(TD-4-AP)could also improve functional recovery after traumatic peripheral nerve injury.Mice with surgical traumatic peripheral nerve injury received TD-4AP or vehicle alone and were examined for skin permeability,pharmacokinetics,functional,electrophysiological,and nerve morphological properties.4-AP showed linear pharmacokinetics and the maximum plasma 4-AP concentrations were proportional to TD-4-AP dose.While a single dose of TD-4-AP administration demonstrated rapid transient improvement in motor function,chronic TD-4-AP treatment significantly improved motor function and nerve conduction and these effects were associated with fewer degenerating axons and thicker myelin sheaths than those from vehicle controls.These findings provide direct evidence for the potential transdermal applicability of 4-AP and demonstrate that 4-AP delivered through the skin can enhance in-vivo functional recovery and nerve conduction while decreasing axonal degeneration.The animal experiments were approved by the University Committee on Animal Research(UCAR)at the University of Rochester(UCAR-2009-019)on March 31,2017. 展开更多
关键词 4-AMINOPYRIDINE electron MICROSCOPY functional recovery NERVE conduction velocity PERIPHERAL NERVE injury PHARMACOKINETICS TRANSDERMAL administration
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Angiogenesis and neuronal remodeling after ischemic stroke 预览
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作者 Masahiro Hatakeyama Itaru Ninomiya Masato Kanazawa 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第1期16-19,共4页
Increased microvessel density in the peri-infarct region has been reported and has been correlated with longer survival times in ischemic stroke patients and has improved outcomes in ischemic animal models.This raises... Increased microvessel density in the peri-infarct region has been reported and has been correlated with longer survival times in ischemic stroke patients and has improved outcomes in ischemic animal models.This raises the possibility that enhancement of angiogenesis is one of the strategies to facilitate functional recovery after ischemic stroke.Blood vessels and neuronal cells communicate with each other using various mediators and contribute to the pathophysiology of cerebral ischemia as a unit.In this mini-review,we discuss how angiogenesis might couple with axonal outgrowth/neurogenesis and work for functional recovery after cerebral ischemia.Angiogenesis occurs within 4 to 7 days after cerebral ischemia in the border of the ischemic core and periphery.Post-ischemic angiogenesis may contribute to neuronal remodeling in at least two ways and is thought to contribute to functional recovery.First,new blood vessels that are formed after ischemia are thought to have a role in the guidance of sprouting axons by vascular endothelial growth factor and laminin/β1-integrin signaling.Second,blood vessels are thought to enhance neurogenesis in three stages:1)Blood vessels enhance proliferation of neural stem/progenitor cells by expression of several extracellular signals,2)microvessels support the migration of neural stem/progenitor cells toward the peri-infarct region by supplying oxygen,nutrients,and soluble factors as well as serving as a scaffold for migration,and 3)oxygenation induced by angiogenesis in the ischemic core is thought to facilitate the differentiation of migrated neural stem/progenitor cells into mature neurons.Thus,the regions of angiogenesis and surrounding tissue may be coupled,representing novel treatment targets. 展开更多
关键词 ANGIOGENESIS AXONAL OUTGROWTH cerebral ischemia coupling functional recovery guidance NEUROGENESIS stroke
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Influence of Aggregate Grain Size on the Formulation of Sand Concrete in the Construction Industry in Congo 预览
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作者 Charlène Bassolokidi Nkengue Narcisse Malanda +2 位作者 Gilbert Ganga Paul Louzolo-Kimbembe Guy Richard Mouengue 《地质材料(英文)》 2019年第4期81-96,共16页
The main objective of this study is to contribute to the optimization of the formulation of sand concretes and its valorisation according to natural sands from different quarries or extraction sites. Physical characte... The main objective of this study is to contribute to the optimization of the formulation of sand concretes and its valorisation according to natural sands from different quarries or extraction sites. Physical characteristics of natural sands have been determined and improved by the addition of crushing sand, taking into account the too fine elements of the sand. Four types of sand were used (Congo River, Djiri, Mfilou, crushed sand). The concrete formulations proposed from improved sands (30% crushed sand and 70% natural sand) reveal an increase in mechanical strength. Thus, it appeared that this improvement of the natural fine sands by the crushing sand has brought a clear increase in the maneuverability of the concretes and the physico-mechanical characteristics of nearly 50%, although this crushing sand has a sand equivalent value of less than 70%. These results augur well for the durability of structures in the construction industry in Congo. 展开更多
关键词 SAND FORMULATION RECOVERY Materials SAND CONCRETE Physico-Mechanical Characteristics Construction
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Differences in neuroplasticity after spinal cord injury in varying animal models and humans 预览
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作者 Mallory E. Filipp Benjamin J. Travis +5 位作者 Stefanie S. Henry Emma C. Idzikowski SarahA. Magnuson Megan YF Loh Daniel J. Hellenbrand Amgad S. Hanna 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第1期7-19,共13页
关键词 动物模型 绳索 损害 四足动物 治疗学 老鼠 运动 小径
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Silver recovery as Ag~0 nanoparticles from ion-exchange regenerant solution using electrolysis
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作者 Tabish Nawaz Sukalyan Sengupta Chen-Lu Yang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第4期161-173,共13页
Many silver(Ag)containing consumer-products(e.g.textiles)release Ag into the environment,posing ecotoxicological risks.Ag recovery mitigates environmental hazards,recycles Ag,and leads to sustainability.In the present... Many silver(Ag)containing consumer-products(e.g.textiles)release Ag into the environment,posing ecotoxicological risks.Ag recovery mitigates environmental hazards,recycles Ag,and leads to sustainability.In the present work,Ag has been recovered as Ag~0nanoparticles from the spent solution(thiourea(TU)~0.5 mol/L pH~1.1–1.2,and Ag~550 mg/L)obtained from the regeneration of an Ag-loaded resin using a simple undivided electrolytic cell.The reclaimed regenerant solution has been recycled and reused in a closed-loop scheme over multiple cycles.The process parameters,i.e.,current(0.05 A)and stirring speed(600 r/min),have been optimized for Ag recovery of~94%and TU loss of~2%.The reclaimed regenerant solution has been shown to regenerate Ag-loaded resin samples with>90%regeneration efficiency over 4 cycles of consecutive extraction and regeneration.The recovered Ag~0nanoparticles are monodisperse,consistently spherical in shape,and have a mean diameter of~6 nm with standard deviation of the Gaussian fit as~2.66 nm. 展开更多
关键词 Silver RECOVERY Ag~0 NANOPARTICLES Waste management THIOUREA Sustainability Resource RECOVERY ELECTROWINNING
Recovery Slope of Heart Rate Variability as an Indicator of Internal Training Load 预览
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作者 José Naranjo Orellana Claudio Nieto-Jiménez José F. Ruso-álvarez 《健康(英文)》 2019年第2期211-221,共11页
The way in which the Root Mean Square of the Successive Differences between adjacent RR intervals (RMSSD) recovers immediately after exercise could be a good indicator of internal training load (ITL). The aim of this ... The way in which the Root Mean Square of the Successive Differences between adjacent RR intervals (RMSSD) recovers immediately after exercise could be a good indicator of internal training load (ITL). The aim of this study is to design a recovery index based on RMSSD. Forteen healthy men took part in this study. The experiment lasted 2 weeks, with 4 separate (48 - 72 h) sessions. First session was an incremental treadmill test to determine ventilatory thresholds (VT1 and VT2) and maximal aerobic speed (MAS). Each subject ran at VT1 speed (second day), VT2 speed (third day) and a time-to-exhaustion test at MAS (fourth day). The duration of VT1 and VT2 loads was selected in such a way that the product intensity-duration (training load) was the same. HRV was measured from 10’ prior to test (Rest) to 30’ after completed (Recovery). Recovery slopes were calculated from RMSSD values at 10 and 30 minutes. Borg scale was recorded at the end of every test and the Training Impulse (TRIMP) values were calculated using Banister equations. The RMSSD values dropped substantially regardless of the intensity and the duration of exercise (average 4 ms). The RMSSD recovery was linear during the 30 min and different depending on the intensity of exercise. To propose a recovery index, we calculated the slope of RMSDD over the 30 minutes (slope-30) and also the first 10 minutes (slope-10). Given that the slopes presented an exponential behavior in relation with effort intensity, three curves were obtained (average values, plus SD and minus SD) defining a nomogram. For practical application, we propose: 1) to measure RMSSD the last 5 minutes of exercise and any period of 5 minutes during the first 30 minutes recovery;2) to calculate the slope of RMSSD between exercise and recovery;3) to compare with the nomogram. 展开更多
关键词 TRAINING LOAD RECOVERY HRV Rmssd PARASYMPATHETIC
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Image Tamper Detection and Multi-Scale Self-Recovery Using Reference Embedding with Multi-Rate Data Protection 预览
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作者 Navid Daneshmandpour Habibollah Danyali Mohammad Sadegh Helfroush 《中国通信:英文版》 SCIE CSCD 2019年第11期154-166,共13页
This paper proposes a multi-scale self-recovery(MSSR)approach to protect images against content forgery.The main idea is to provide more resistance against image tampering while enabling the recovery process in a mult... This paper proposes a multi-scale self-recovery(MSSR)approach to protect images against content forgery.The main idea is to provide more resistance against image tampering while enabling the recovery process in a multi-scale quality manner.In the proposed approach,the reference data composed of several parts and each part is protected by a channel coding rate according to its importance.The first part,which is used to reconstruct a rough approximation of the original image,is highly protected in order to resist against higher tampering rates.Other parts are protected with lower rates according to their importance leading to lower tolerable tampering rate(TTR),but the higher quality of the recovered images.The proposed MSSR approach is an efficient solution for the main disadvantage of the current methods,which either recover a tampered image in low tampering rates or fails when tampering rate is above the TTR value.The simulation results on 10000 test images represent the efficiency of the multi-scale self-recovery feature of the proposed approach in comparison with the existing methods. 展开更多
关键词 tamper detection image recovery multi-scale self-recovery tolerable tampering rate
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Truncated sparse approximation property and truncated q-norm minimization 预览
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作者 CHEN Wen-gu LI Peng 《高校应用数学学报:英文版(B辑)》 SCIE CSCD 2019年第3期261-283,共23页
This paper considers approximately sparse signal and low-rank matrix’s recovery via truncated norm minimization minx∥xT∥q and minX∥XT∥Sq from noisy measurements.We first introduce truncated sparse approximation p... This paper considers approximately sparse signal and low-rank matrix’s recovery via truncated norm minimization minx∥xT∥q and minX∥XT∥Sq from noisy measurements.We first introduce truncated sparse approximation property,a more general robust null space property,and establish the stable recovery of signals and matrices under the truncated sparse approximation property.We also explore the relationship between the restricted isometry property and truncated sparse approximation property.And we also prove that if a measurement matrix A or linear map A satisfies truncated sparse approximation property of order k,then the first inequality in restricted isometry property of order k and of order 2k can hold for certain different constantsδk andδ2k,respectively.Last,we show that ifδs(k+|T^c|)<√(s-1)/s for some s≥4/3,then measurement matrix A and linear map A satisfy truncated sparse approximation property of order k.It should be pointed out that when Tc=Ф,our conclusion implies that sparse approximation property of order k is weaker than restricted isometry property of order sk. 展开更多
关键词 TRUNCATED NORM MINIMIZATION TRUNCATED SPARSE approximation PROPERTY restricted isometry PROPERTY SPARSE signal RECOVERY low-rank matrix RECOVERY Dantzig selector
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The impact of connate water saturation and salinity on oil recovery and CO2 storage capacity during carbonated water injection in carbonate rock
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作者 Mahmood Shakiba Masoud Riazi +1 位作者 Shahab Ayatollahi Mostafa Takband 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第7期1699-1707,共9页
Carbonated water injection(CWI)is known as an efficient technique for both CO2 storage and enhanced oil recovery(EOR).During CWI process,CO2 moves from the water phase into the oil phase and results in oil swelling.Th... Carbonated water injection(CWI)is known as an efficient technique for both CO2 storage and enhanced oil recovery(EOR).During CWI process,CO2 moves from the water phase into the oil phase and results in oil swelling.This mechanism is considered as a reason for EOR.Viscous fingering leading to early breakthrough and leaving a large proportion of reservoir un-swept is known as an unfavorable phenomenon during flooding trials.Generally,instability at the interface due to disturbances in porous medium promotes viscous fingering phenomenon.Connate water makes viscous fingers longer and more irregular consisting of large number of tributaries leading to the ultimate oil recovery reduction.Therefore,higher in-situ water content can worsen this condition.Besides,this water can play as a barrier between oil and gas phases and adversely affect the gas diffusion,which results in EOR reduction.On the other hand,from gas storage point of view,it should be noted that CO2 solubility is not the same in the water and oil phases.In this study for a specified water salinity,the effects of different connate water saturations(Swc)on the ultimate oil recovery and CO2 storage capacity during secondary CWI are being presented using carbonate rock samples from one of Iranian carbonate oil reservoir.The results showed higher oil recovery and CO2 storage in the case of lower connate water saturation,as 14%reduction of Swc resulted in 20%and 16%higher oil recovery and CO2 storage capacity,respectively. 展开更多
关键词 Carbonated WATER Connate WATER CARBONATE reservoir Enhanced oil RECOVERY SECONDARY RECOVERY CO2 storage
Utility of the “RMSSD-Slope” to Assess the Internal Load in Different Sports Situations 预览
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作者 José F. Ruso-álvarez Claudio Nieto-Jiménez +1 位作者 Alejandro Mu?oz-López José Naranjo Orellana 《健康(英文)》 2019年第6期683-691,共9页
The control of training load has become a very interesting field for investigation in sports, but few tools are used to assess internal training load (ITL). The aim of this study is to use a post-exercise analysis met... The control of training load has become a very interesting field for investigation in sports, but few tools are used to assess internal training load (ITL). The aim of this study is to use a post-exercise analysis methodology in different athletes and situations to establish its utility and reliability as a measure of ITL. In a retrospective review, we analysed 112 measurements of 74 subjects (38 men and 36 women) grouped in: University students (UNI);national team (FUTSAL 1);university team (FUTSAL 2);athletes (ATL);badminton players (BADM). Measures of Heart Rate Variability (HRV) were made with a Polar V800 with a thoracic band H10, during 5 minutes in a seated position after exercise. We calculated the Root Mean Square of the successive differences between adjacent RR intervals (RMSSD) and its slope from exercise to recovery. Measurements from UNI, FUTSAL-2, ATL-M and ATL-F were grouped into three categories of intensity (60%, 75% and 100%). RMSSD-Slope values were lower as intensity increased but different for every subject. In the BADM and FUTSAL-1 groups, RMSSD-Slope was progressively lower after consecutive matches for every player. The RMSSD-Slope seems to be a very accurate method to assess ITL. 展开更多
关键词 HRV Training LOAD rMSSD RECOVERY
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Effect of Sodium Oleate Concentration Variations on Froth Flotation of Manganese Ore 预览
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作者 Ogundeji Frncis Oladapo Alabi Oladunni 《有色冶金(英文)》 2019年第3期25-33,共9页
Each type of a manganese deposit is a problem by itself in the matter of selection of a proper method of concentration, depending on the manganese minerals and their gangue constituents. Hence, this work studied the e... Each type of a manganese deposit is a problem by itself in the matter of selection of a proper method of concentration, depending on the manganese minerals and their gangue constituents. Hence, this work studied the effect of sodium oleate concentration variation on the froth flotation of manganese ore obtained from Madaka, Niger State, Nigeria. The chemical analysis of the ore shows that it contains 48.4% MnO (37.5% Mn). Peaks were identified in XRD analysis of the crude sample as that of magnosite (MnO), hausmannite (Mn3O4), spessartine and vemuculite (Mg, Fe2+, Fe3+)3[(AlSiO4)O10](OH)2·4H2O. The ore was beneficiated by froth flotation using sodium oleate as collector at varied concentrations of 3 g/kg, 7 g/kg and 10 g/kg. Other chemical reagents used were sodium silicate, fuel oil and calcium hydroxide as dispersant, frother and pH modifier respectively. Results obtained showed percentage metal recoveries of 9.29%, 14.30% and 19.61%, assaying 65.20%, 62.03% and 61.30% Mn respectively. This indicates that at sodium oleate concentration of 3 g/kg, high grade-concentrate can be obtained. 展开更多
关键词 MANGANESE ORE SODIUM OLEATE Comminution BENEFICIATION Recovery
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马钢2号高炉炉况处理实践 预览
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作者 尤石 曹海 +1 位作者 陶华 赵淑文 《安徽冶金科技职业学院学报》 2019年第2期25-28,共4页
对马钢2号高炉炉况波动的原因和处理进行了总结。2号高炉投产不久,也就是2018年2月中下旬炉况出现波动,从高炉上下部制度、焦炭的库存和质量等方面进行分析,并根据炉况波动不同的阶段采取相应措施,避免了炉况失常,实现炉况根本性的好转... 对马钢2号高炉炉况波动的原因和处理进行了总结。2号高炉投产不久,也就是2018年2月中下旬炉况出现波动,从高炉上下部制度、焦炭的库存和质量等方面进行分析,并根据炉况波动不同的阶段采取相应措施,避免了炉况失常,实现炉况根本性的好转,产量大幅度提高,取得较好效果。 展开更多
关键词 高炉 炉况处理 焦炭 恢复
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山西某铅金混合精矿铅金分离试验 预览
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作者 廖银英 杨远坤 +1 位作者 吴双桥 吕兵超 《有色金属:选矿部分》 CAS 北大核心 2019年第1期53-56,共4页
针对山西某金矿选矿厂铅金混合精矿铅未达到销售计价的品位、导致矿石价值下降的问题。试验采用一次粗选两次扫选两次精选的工艺流程,闭路试验可获得Pb品位60. 35%、含Au 54. 06 g/t、含Ag 2 708. 80 g/t的铅精矿,铅回收率为59. 41%、A... 针对山西某金矿选矿厂铅金混合精矿铅未达到销售计价的品位、导致矿石价值下降的问题。试验采用一次粗选两次扫选两次精选的工艺流程,闭路试验可获得Pb品位60. 35%、含Au 54. 06 g/t、含Ag 2 708. 80 g/t的铅精矿,铅回收率为59. 41%、Au回收率26. 05%、Ag回收率37. 79%;Au品位33. 34 g/t、Ag品位968. 97 g/t的金精矿,Au回收率为73. 95%、Ag回收率62. 21%。该工艺可使矿石中方铅矿得到充分回收利用,同时不影响金银的总回收率,提高了选矿厂的经济效益。 展开更多
关键词 铅金混合精矿 铅金分离 浮选 回收率
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电动汽车制动能量回收控制系统的设计 预览
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作者 马文静 《常州信息职业技术学院学报》 2019年第3期35-38,共4页
根据电动汽车的工作特性,设计了电动汽车制动能量回收控制系统。该控制系统以单片机为主控制器,控制永磁直流电机、IGBT、蓄电池组、机械传动系统等协调工作,来达到有效回收制动能量的目的。此控制系统操作简单、设计合理、可靠性高,有... 根据电动汽车的工作特性,设计了电动汽车制动能量回收控制系统。该控制系统以单片机为主控制器,控制永磁直流电机、IGBT、蓄电池组、机械传动系统等协调工作,来达到有效回收制动能量的目的。此控制系统操作简单、设计合理、可靠性高,有效提高了电动车的续航能力。 展开更多
关键词 电动汽车 制动能量 回收
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Transplantation of adult spinal cord grafts into spinal cord transected rats improves their locomotor function
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作者 He Shen Xi Chen +3 位作者 Xing Li Ke Jia Zhifeng Xiao Jianwu Dai 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第6期725-733,共9页
Grafted embryonic central neural tissue pieces can recover function of hemisected spinal cord in neonatal rats and promote axonal growth in adults. However, spinal cord segments from adults have not been used as donor... Grafted embryonic central neural tissue pieces can recover function of hemisected spinal cord in neonatal rats and promote axonal growth in adults. However, spinal cord segments from adults have not been used as donor segments for allogeneic transplantation. Here, we utilized adult spinal cord tissue grafts(aSCGs) as donor constructs for repairing complete spinal cord injury(SCI). Moreover, to provide a favourable microenvironment for SCI treatment, a growth factor cocktail containing three growth factors(brain-derived neurotrophic factor, neurotrophin-3 and vascular endothelial growth factor), was applied to the aSCG transplants. We found that the locomotor function was significantly improved 12 weeks after transplantation of aSCGs into the spinal cord lesion site in adult rats. Transplantation of aSCGs combined with these growth factors enhanced neuron and oligodendrocyte survival and functional restoration. These encouraging results indicate that treatment of complete SCI by transplanting aSCGs, especially in the presence of growth factors, has a positive effect on motor functional recovery, and therefore could be considered as a possible therapeutic strategy for SCI. 展开更多
关键词 SPINAL CORD injury (SCI) TRANSPLANTATION ADULT SPINAL CORD GRAFTS (aSCGs) function recovery ADULT host transection
Stabilizing silica nan oparticles in high saline water by using polyvinylpyrrolidone for reduction of asphaltene precipitation damage under dynamic condition
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作者 Mohammad Reza Aghajanzadeh Mohammad Sharifi 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第5期1021-1029,共9页
In this study, the performance of stable nanofluid containing SiO2 nanoparticles dispersed and stabilized in high salinity brine for asphaltene inhibition in dynamic condition is evaluated. In the first stage of this ... In this study, the performance of stable nanofluid containing SiO2 nanoparticles dispersed and stabilized in high salinity brine for asphaltene inhibition in dynamic condition is evaluated. In the first stage of this work, the stability of silica nanoparticles in different range of water salinity(0–100000 mg·L-1) is investigated. Next, stable nanofluid containing highest salinity is selected as asphaltene inhibitor agent to inject into the damaged core sample. The estimated values of oil recovery for base case, after damage process and after inhibition of asphaltene precipitation using nanofluid are 51.6%, 36.1% and 46.7%, respectively. The results showed the reduction in core damage after using nanofluid. In addition, the relative permeability curves are plotted for the base case, after damage process and also after inhibition of asphaltene precipitation using nanofluid. Comparison of relative permeability curves shows, relative permeability of oil phase decreased after damage process as compared with the base case. But after using nanofluid the oil relative permeability curve has shifted to the right and effective permeability of oil phase has been improved. 展开更多
关键词 Formation DAMAGE Enhanced oil recovery SALINITY ASPHALTENE Core FLOODING Nano particles
全程恒温管理预防低体温对TURP术后患者机体康复的影响 预览
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作者 甘蔚明 詹至柔 +1 位作者 江敏仪 谢慈妹 《临床医学工程》 2019年第11期1589-1590,共2页
目的分析全程恒温管理对经尿道前列腺切除术(TURP)术后患者机体康复的影响。方法将2018年1月至2018年5月行TURP的50例患者作为对照组,给予常规护理;将2018年6月至2018年12月行TURP的50例患者作为实验组,给予全程恒温管理。两组患者在入... 目的分析全程恒温管理对经尿道前列腺切除术(TURP)术后患者机体康复的影响。方法将2018年1月至2018年5月行TURP的50例患者作为对照组,给予常规护理;将2018年6月至2018年12月行TURP的50例患者作为实验组,给予全程恒温管理。两组患者在入室时、术中30 min、 60 min、 90 min、 120 min和术毕均测量记录体温,统计两组的寒战发生率、疼痛评分和肠道功能恢复情况。结果实验组术中30 min、 60 min、 90 min、 120 min和术毕的体温均高于对照组(P <0.05)。实验组术后肠鸣音恢复时间和首次肛门排气时间均短于对照组,寒战发生率和疼痛评分低于对照组(P均<0.05)。结论对TURP患者行全程恒温管理,能降低低体温和术后寒战发生率,促进肠道功能恢复,减轻术后疼痛,提高患者术后机体康复效果。 展开更多
关键词 全程恒温管理 低体温 TURP 康复 影响
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