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Autonomic laterality in caloric vestibular stimulation 被引量:2
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作者 Mohammadreza Aghababaei Ziarati Mohammad Hosein Taziki Seyed Mehran Hosseini 《World Journal of Cardiology》 CAS 2020年第4期144-154,共11页
BACKGROUND Caloric stimulation of the vestibular system is associated with autonomic response.The lateralization in the nervous system activities also involves the autonomic nervous system.AIM To compare the effect of... BACKGROUND Caloric stimulation of the vestibular system is associated with autonomic response.The lateralization in the nervous system activities also involves the autonomic nervous system.AIM To compare the effect of the right and left ear caloric test on the cardiac sympathovagal tone in healthy persons.METHODS This self-control study was conducted on 12 healthy male volunteers.The minimal ice water caloric test was applied for vestibular stimulation.This was done by irrigating 1 milliliter of 4±2°C ice water into the external ear canal in 1 s.In each experiment,only one ear was stimulated.For each ear,the pessimum position was considered as sham control and the optimum position was set as caloric vestibular stimulation of horizontal semicircular channel.The order of right or left caloric vestibular stimulation and the sequence of optimum or pessimum head position in each set were random.The recovery time between each calorie test was 5 min.The short-term heart rate variability(HRV)was used for cardiac sympathovagal tone metrics.All variables were compared using the analysis of variance.RESULTS After caloric vestibular stimulation,the short-term time-domain and frequencydomain HRV indices as well as,the systolic and the diastolic arterial blood pressure,the respiratory rate and the respiratory amplitude,had no significant changes.These negative results were similar in the right and the left sides.Nystagmus duration of left caloric vestibular stimulations in the optimum and the pessimum positions had significant differences(e.g.,72.14±39.06 vs 45.35±35.65,P<0.01).Nystagmus duration of right caloric vestibular stimulations in the optimum and the pessimum positions had also significant differences(e.g.,86.42±67.20 vs 50.71±29.73,P<0.01).The time of the start of the nystagmus following caloric vestibular stimulation had no differences in both sides and both positions.CONCLUSION Minimal ice water caloric stimulation of the right and left vestibular system did not affect the cardiac sympathovagal balance according to HRV indices. 展开更多
关键词 Caloric STIMULATION HEART rate VARIABILITY VESTIBULAR system AUTONOMIC laterality
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The Association between Surgery Laterality in Orthopedists and the Choices of Prostheses in Total Knee and Hip Replacement 被引量:2
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作者 Jui-Yang Hsieh Ming-Shu Lan +1 位作者 Ying-Hsiu Chang Jyh-Horng Wang 《Open Journal of Orthopedics》 2018年第7期257-266,共10页
Background: Most orthopedists are right-handed. However, osteoarthritis occurs with equal frequency over both sides. Does perfect and effective arthroplasty surgery require ambidextrous motor skills? Objectives: In th... Background: Most orthopedists are right-handed. However, osteoarthritis occurs with equal frequency over both sides. Does perfect and effective arthroplasty surgery require ambidextrous motor skills? Objectives: In this study, we aimed to investigate the clinical features of arthroplasty for hip and knee joints (THR and TKR) on different sides affected by orthopedist laterality. Patients and Methods: All right-handed orthopedists performed 64 right and 52 left primary THR among 100 patients, and 115 right and 118 left primary TKR among 192 patients. Clinical and surgical features were retrospectively reviewed and analyzed. The body mass index (BMI), inner diameter of acetabular cup liners (ACD), diameter of the femoral head (FHD), diameter of the femoral stem (FSD), and the femoral neck length (FNL) were included in THR-receiving patients. The BMI, femoral component (FC) size, tibial plate (TP) size, and thickness of articular surface inserts (ASI) were included in TKR-receiving patients. Results: No significant differences were observed in ACD, FHD and FSD between patients receiving right and left THR groups (p = 0.16, 0.11, and 0.05, respectively). Similarly, there were no significant differences in FC, TP, and ASI between patients receiving right and left TKR groups (p = 0.06, 0.80, and 0.46, respectively). However, FNL in left THR group was significantly longer than that in right THR group (p = 0.01). Conclusion: This study showed that dexterity or proprioception in handedness had no affect on bone resection and thicknesses of the polyethylene in TKR and acetabular reaming and femoral canal rasping in THR. However, it did lead to differences in femoral neck resection. Right-handed orthopedists significantly tend to perform excessive femoral neck cutting or prefer the larger size of FNL when performing left side THR, while no differences occur when performing TKR. 展开更多
关键词 TOTAL Hip REPLACEMENT TOTAL Knee REPLACEMENT HANDEDNESS laterality
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Neural control of the soleus H-reflex correlates tothe laterality pattern in limbs
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作者 Dorota Olex-Zarychta 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第5期390-395,共6页
BACKGROUND: Previous studies have demonstrated the relationship of lower limb dominance with left- and right-handedness, supporting findings suggest that there is a role for peripheral factors in the neural control o... BACKGROUND: Previous studies have demonstrated the relationship of lower limb dominance with left- and right-handedness, supporting findings suggest that there is a role for peripheral factors in the neural control of movement. OBJECTIVE: To investigate the effect of laterality pattern on the neural mechanisms of motor control at the peripheral level. DESIGN, TIME AND SETTING: A controlled observation experiment was performed at the Motor Diagnostics Laboratory of the Academy of Physical Education in Katowice, Poland, in June 2009. PARTICIPANTS: Twenty young male adults aged 21-23 years and presenting two laterality patterns in hand-foot combination (right handed-right footed and left handed-left footed groups) took part in the experiment. All participants were carefully screened to eliminate any neurological or muscle disease or trauma. METHODS: The experiment included a laterality evaluation and the motor evoked potentials of dominant and non-dominant limbs. Measures were done through the use of the Hoffmann-reflex (H-reflex) circuitry. The soleus H-reflex parameters elicited at rest in lower extremities were compared. The soleus H-reflex and the direct motor response were elicited in lower extremities of each participant in the same laboratory session. MAIN OUTCOME MEASURES: Onset latencies and min-max amplitudes of the direct motor response and the H-reflex; the motor and sensory conduction velocities; and symmetry coefficients of response parameters. RESULTS: The analysis of symmetry coefficients of direct and late motor responses confirmed differences between two laterality patterns in amplitude and latency of the H-reflex as well as in a sensory conduction velocity (P 〈 0.05), but not in direct motor response parameters. The amplitude of the H-reflex and the calculated sensory la afferent conduction velocity in the dominant lower extremity were significantly depressed in the right-sided group in comparison to the left-sided group (P = 0.001). The right-sided group presented significantly higher motor fiber conduction velocity in the dominant leg than in the non-dominant leg (P = 0.006), with no similar effect in the left-sided group. CONCLUSION: The neural control of the H-reflex elicited at rest is related to the laterality pattern in hand-foot combination in healthy adults. This result strongly suggests the possible existence of intrinsic control mechanisms of afferent feedback related to functional dominance in human limbs. 展开更多
关键词 Hoffmann-reflex laterality motor control neural circuitry human peripheral factors
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Comparison of strength values and laterality in various muscle contractions between competitive swimmers and untrained persons
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作者 Shinichi Demura Hiroki Aoki +1 位作者 Yuta Yamamoto Shunsuke Yamaji 《Health》 2010年第11期1249-1254,共6页
Competitive swimmers may gain a specific training effect as the result of long term exercise in the water. This study aimed to compare isometric, non-isokinetic and isokinetic muscle strengths in competitive swimmers ... Competitive swimmers may gain a specific training effect as the result of long term exercise in the water. This study aimed to compare isometric, non-isokinetic and isokinetic muscle strengths in competitive swimmers and untrained persons. Twelve young male adults without exercise experience for over three years and twelve swimmers with over 10 years of competitive swimming experience performed various strength tests. Non-isokinetic tests were evaluated using one repetition of maximum half squat, vertical jump, and drop jump. Isometric and isokinetic (60 and 180 deg/s) muscle strengths were measured by both legs in knee extension and flexion. There were no significant differences between non-isokinetic and isometric muscle strengths of both groups. On the other hand, all isokinetic parameters in both angular velocities were significantly larger in competitive swimmers. There was significant laterality of isokinetic strength in untrained persons, but not in competitive swimmers. In addition, right and left differences of isokinetic strength tended to be smaller in competitive swimmers. In conclusion, competitive swimmers tended to be superior only in isokinetic strength, which is a similar muscle contraction in the water, and have less right and left differences. 展开更多
关键词 Lsokinetic STRENGTH Lsometric STRENGTH KNEE Extension and FLEXION laterality
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Microglial Depletion does not Afect the Laterality of Mechanical Allodynia in Mice
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作者 Quan Ma Dongmei Su +10 位作者 Jiantao Huo Guangjuan Yin Dong Dong Kaifang Duan Hong Cheng Huiling Xu Jiao Ma Dong Liu Bin Mou Jiyun Peng Longzhen Cheng 《Neuroscience Bulletin》 SCIE CAS CSCD 2023年第8期1229-1245,共17页
Mechanical allodynia(MA),including punctate and dynamic forms,is a common and debilitating symptom suffered by millions of chronic pain patients.Some peripheral injuries result in the development of bilateral MA,while... Mechanical allodynia(MA),including punctate and dynamic forms,is a common and debilitating symptom suffered by millions of chronic pain patients.Some peripheral injuries result in the development of bilateral MA,while most injuries usually led to unilateral MA.To date,the control of such laterality remains poorly understood.Here,to study the role of microglia in the control of MA laterality,we used genetic strategies to deplete microglia and tested both dynamic and punctate forms of MA in mice.Surprisingly,the depletion of central microglia did not prevent the induction of bilateral dynamic and punctate MA.Moreover,in dorsal root ganglion-dorsal root-sagittal spinal cord slice preparations we recorded the low-threshold Aβ-fiber stimulation-evoked inputs and outputs of superficial dorsal horn neurons.Consistent with behavioral results,microglial depletion did not prevent the opening of bilateral gates for Aβpathways in the superficial dorsal horn.This study challenges the role of microglia in the control of MA laterality in mice.Future studies are needed to further understand whether the role of microglia in the control of MA laterality is etiology-or species-specific. 展开更多
关键词 MICROGLIA Mechanical allodynia laterality Spinal dorsal horn Dynamic allodynia Punctate allodynia
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Novel approach of ultrasound-guided lateral recess block for a patient with lateral recess stenosis: A case report 被引量:1
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作者 Jiao Yang Xin-Ling Li Qing-Bing Li 《World Journal of Clinical Cases》 SCIE 2024年第5期1010-1017,共8页
BACKGROUND Ultrasound guide technology,which can provide real-time visualization of the needle tip and tissues and avoid many adverse events,is widely used in mini-mally invasive therapy.However,the studies on ultraso... BACKGROUND Ultrasound guide technology,which can provide real-time visualization of the needle tip and tissues and avoid many adverse events,is widely used in mini-mally invasive therapy.However,the studies on ultrasound-guided Lateral recess block(LRB)are limited,this is probably because there is no recognized standard method for ultrasound scanning.This study aimed to evaluate the effect of ultrasound-guided LRB in patients with lateral recess stenosis(LRS).CASE SUMMARY A 65-year-old patient complained of low back pain accompanied occasionally by pain and numbness in the left lower limb.Physical examination showed ten-derness on the spinous process and paraspinal muscles from L1 to S1,extensor hallucis longus and tibialis anterior weakness(muscle strength:4-),and a positive straight leg raising test in the left lower limb(60°).Magnetic resonance imaging showed L4–L5 disc degeneration with left LRS and nerve root entrapment.Subsequently,the patient was diagnosed with LRS.This patient was treated with a novel ultrasound-guided LRB approach.The patient’s symptoms significantly improved without any complications at 1 wk postoperatively and at the 3-month follow-up.CONCLUSION This is the first report on the LRS treatment with ultrasound-guided LRB from the contralateral spinous process along the inner side of the articular process by out-plane technique.Further studies are expected to investigate the efficacy and safety of ultrasound-guided LRB for patients with LRS. 展开更多
关键词 Lateral recess stenosis ULTRASOUND Lateral recess block Real-time visualization Low back pain Case report
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Lateral earth pressure of granular backfills on retaining walls with expanded polystyrene geofoam inclusions under limited surcharge loading 被引量:1
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作者 Kewei Fan Guangqing Yang +2 位作者 Weilie Zou Zhong Han Yang Shen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1388-1397,共10页
Existing studies have focused on the behavior of the retaining wall equipped with expanded polystyrene(EPS)geofoam inclusions under semi-infinite surcharge loading rather than limited surcharge loading.In this paper,t... Existing studies have focused on the behavior of the retaining wall equipped with expanded polystyrene(EPS)geofoam inclusions under semi-infinite surcharge loading rather than limited surcharge loading.In this paper,the failure mode and the earth pressure acting on the rigid retaining wall with EPS geofoam inclusions and granular backfills(henceforth referred to as EPS-wall),under limited surcharge loading are investigated through two-and three-dimensional model tests.The testing results show that different from the sliding of almost all the backfill in the EPS-wall under semi-infinite surcharge loading,only an approximately triangular backfill slides in the wall under limited surcharge loading.The distribution of the lateral earth pressure on the EPS-wall under limited surcharge loading is non-linear,and the distribution changes from the increase of the wall depth to the decrease with the increase of the limited surcharge loading.An approach based on the force equilibrium of a differential element is developed to predict the lateral earth pressure behind the EPS-wall subjected to limited surcharge loading,and its performance was fully validated by the three-dimensional model tests. 展开更多
关键词 Retaining wall Expanded polystyrene(EPS)geofoam Limited surcharge loading Lateral earth pressure Model test Prediction
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Antisense therapy:a potential breakthrough in the treatment of neurodegenerative diseases 被引量:1
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作者 Roberta Romano Cecilia Bucci 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1027-1035,共9页
Neurodegenerative diseases are a group of disorders characterized by the progressive degeneration of neurons in the central or peripheral nervous system.Currently,there is no cure for neurodegenerative diseases and th... Neurodegenerative diseases are a group of disorders characterized by the progressive degeneration of neurons in the central or peripheral nervous system.Currently,there is no cure for neurodegenerative diseases and this means a heavy burden for patients and the health system worldwide.Therefore,it is necessary to find new therapeutic approaches,and antisense therapies offer this possibility,having the great advantage of not modifying cellular genome and potentially being safer.Many preclinical and clinical studies aim to test the safety and effectiveness of antisense therapies in the treatment of neurodegenerative diseases.The objective of this review is to summarize the recent advances in the development of these new technologies to treat the most common neurodegenerative diseases,with a focus on those antisense therapies that have already received the approval of the U.S.Food and Drug Administration. 展开更多
关键词 Alzheimer’s disease amyotrophic lateral sclerosis antisense oligonucleotide Huntington’s disease neurodegenerative disorders Parkinson’s disease SIRNA
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The role of exosomes in adult neurogenesis:implications for neurodegenerative diseases 被引量:1
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作者 Zhuoyang Yu Yan Teng +1 位作者 Jing Yang Lu Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期282-288,共7页
Exosomes are cup-shaped extracellular vesicles with a lipid bilayer that is approximately 30 to 200 nm in thickness.Exosomes are widely distributed in a range of body fluids,including urine,blood,milk,and saliva.Exoso... Exosomes are cup-shaped extracellular vesicles with a lipid bilayer that is approximately 30 to 200 nm in thickness.Exosomes are widely distributed in a range of body fluids,including urine,blood,milk,and saliva.Exosomes exert biological function by transporting factors between different cells and by regulating biological pathways in recipient cells.As an important form of intercellular communication,exosomes are increasingly being investigated due to their ability to transfer bioactive molecules such as lipids,proteins,mRNAs,and microRNAs between cells,and because they can regulate physiological and pathological processes in the central nervous system.Adult neurogenesis is a multistage process by which new neurons are generated and migrate to be integrated into existing neuronal circuits.In the adult brain,neurogenesis is mainly localized in two specialized niches:the subventricular zone adjacent to the lateral ventricles and the subgranular zone of the dentate gyrus.An increasing body of evidence indicates that adult neurogenesis is tightly controlled by environmental conditions with the niches.In recent studies,exosomes released from different sources of cells were shown to play an active role in regulating neurogenesis both in vitro and in vivo,thereby participating in the progression of neurodegenerative disorders in patients and in various disease models.Here,we provide a state-of-the-art synopsis of existing research that aimed to identify the diverse components of exosome cargoes and elucidate the therapeutic potential of exosomal contents in the regulation of neurogenesis in several neurodegenerative diseases.We emphasize that exosomal cargoes could serve as a potential biomarker to monitor functional neurogenesis in adults.In addition,exosomes can also be considered as a novel therapeutic approach to treat various neurodegenerative disorders by improving endogenous neurogenesis to mitigate neuronal loss in the central nervous system. 展开更多
关键词 adult neurogenesis Alzheimer’s disease amyotrophic lateral sclerosis EXOSOME Huntington’s disease neurodegenerative disease neurogenic niches Parkinson’s disease
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A dual-RPA based lateral flow strip for sensitive,on-site detection of CP4-EPSPS and Cry1Ab/Ac genes in genetically modified crops 被引量:1
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作者 Jinbin Wang Yu Wang +7 位作者 Xiuwen Hu Yifan Chen Wei Jiang Xiaofeng Liu Juan Liu Lemei Zhu Haijuan Zeng Hua Liu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期183-190,共8页
Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSP... Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field. 展开更多
关键词 Genetically modifi ed crops On-site detection Lateral fl ow test strips Dual recombinase polymerase amplification (RPA)
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Laterality of brain areas associated with arithmetic calculations revealed by functional magnetic resonance imaging 被引量:2
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作者 HANGYun-ting ZHANGQuan ZHANGJing LIWei 《Chinese Medical Journal》 SCIE CAS CSCD 2005年第8期633-638,共6页
Background Asymmetry of bilateral cerebral function, i.e. laterality, is an important phenomenon in many brain actions: arithmetic calculation may be one of these phenomena. In this study, first, laterality of brain... Background Asymmetry of bilateral cerebral function, i.e. laterality, is an important phenomenon in many brain actions: arithmetic calculation may be one of these phenomena. In this study, first, laterality of brain areas associated with arithmetic calculations was revealed by functional magnetic resonance imaging (fMRI). Second, the relationship among laterality, handedness, and types of arithmetic task was assessed. Third, we postulate possible reasons for laterality. Methods Using a block-designed experiment, twenty-five right-handed and seven left-handed healthy volunteers carried out simple calculations, complex calculations and proximity judgments. T 1WI and GRE-EPI fMRI were performed with a GE 1.5T whole body MRI scanner. Statistical parametric mapping (SPM99) was used to process data and localize functional areas. Numbers of activated voxels were recorded to calculate laterality index for evaluating the laterality of functional brain areas. Results For both groups, the activation of functional areas in the frontal lobe showed a tendency towards the nonpredominant hand side, but the functional areas in the inferior parietal lobule had left laterality. During simple and complex calculations, the laterality indices of the prefrontal cortex and premotor area were higher in the right-handed group than that in the left-handed group, whereas the laterality of the inferior parietal lobule had no such significant difference. In both groups, when the difficulty of the task increased, the laterality of the prefrontal cortex, premotor area, and inferior parietal lobule decreased, but the laterality of posterior part of the inferior frontal gyrus increased. Conclusions The laterality of the functional brain areas associated with arithmetic calculations can be detected with fMRI. The laterality of the functional areas was related to handedness and task difficulty. 展开更多
关键词 magnetic resonance imaging functional arithmetic calculation cerebral cortex COGNITION laterality
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Pathological mechanisms of amyotrophic lateral sclerosis
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作者 Yushu Hu Wenzhi Chen +4 位作者 Caihui Wei Shishi Jiang Shu Li Xinxin Wang Renshi Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1036-1044,共9页
Amyotrophic lateral sclerosis refers to a neurodegenerative disease involving the motor system,the cause of which remains unexplained despite several years of research.Thus,the journey to understanding or treating amy... Amyotrophic lateral sclerosis refers to a neurodegenerative disease involving the motor system,the cause of which remains unexplained despite several years of research.Thus,the journey to understanding or treating amyotrophic lateral sclerosis is still a long one.According to current research,amyotrophic lateral sclerosis is likely not due to a single factor but rather to a combination of mechanisms mediated by complex interactions between molecular and genetic pathways.The progression of the disease involves multiple cellular processes and the interaction between different complex mechanisms makes it difficult to identify the causative factors of amyotrophic lateral sclerosis.Here,we review the most common amyotrophic lateral sclerosis-associated pathogenic genes and the pathways involved in amyotrophic lateral sclerosis,as well as summarize currently proposed potential mechanisms responsible for amyotrophic lateral sclerosis disease and their evidence for involvement in amyotrophic lateral sclerosis.In addition,we discuss current emerging strategies for the treatment of amyotrophic lateral sclerosis.Studying the emergence of these new therapies may help to further our understanding of the pathogenic mechanisms of the disease. 展开更多
关键词 amyotrophic lateral sclerosis cellular pathways disease mechanisms motor neuron neurodegenerative disease
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Deformation Characteristics of Hydrate-Bearing Sediments
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作者 DONG Lin LI Yanlong +4 位作者 ZHANG Yajuan HU Gaowei LIAO Hualin CHEN Qiang WU Nengyou 《Journal of Ocean University of China》 CAS CSCD 2024年第1期149-156,共8页
The safe and efficient development of natural gas hydrate requires a deep understanding of the deformation behaviors of reservoirs.In this study,a series of triaxial shearing tests are carried out to investigate the d... The safe and efficient development of natural gas hydrate requires a deep understanding of the deformation behaviors of reservoirs.In this study,a series of triaxial shearing tests are carried out to investigate the deformation properties of hydrate-bearing sediments.Variations of volumetric and lateral strains versus hydrate saturation are analyzed comprehensively.Results indicate that the sediments with high hydrate saturation show dilative behaviors,which lead to strain-softening characteristics during shearing.The volumetric strain curves have a tendency to transform gradually from dilatation to compression with the increase in effective confining pressure.An easy prediction model is proposed to describe the relationship between volumetric and axial strains.The model coefficientβis the key dominating factor for the shape of volumetric strain curves and can be determined by the hydrate saturation and stress state.Moreover,a modified model is established for the calculation of lateral strain.The corresponding determination method is provided for the easy estimation of model coefficients for medium sand sediments containing hydrate.This study provides a theoretical and experimental reference for deformation estimation in natural gas hydrate development. 展开更多
关键词 gas hydrate deformation characteristics volumetric strain lateral strain prediction model
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At-rest lateral earth pressure of compacted expansive soils:Experimental investigations and prediction approach
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作者 Zhong Han Pan Zhang +3 位作者 Weilie Zou Kewei Fan Sai K.Vanapalli Lianglong Wan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1425-1435,共11页
This paper presents experimental studies on a compacted expansive soil,from Nanyang,China for investigating the at-rest lateral earth pressureσL of expansive soils.The key studies include(i)relationships between the... This paper presents experimental studies on a compacted expansive soil,from Nanyang,China for investigating the at-rest lateral earth pressureσL of expansive soils.The key studies include(i)relationships between theσL and the vertical stressσV during soaking and consolidation,(ii)the influences of initial dry densityρd0 and moisture content w 0 on the vertical and lateral swelling pressures at no swelling strain(i.e.σV0 andσL0),and(iii)evolution of theσL during five long-term wetting-drying cycles.Experimental results demonstrated that the post-soakingσL-σV relationships are piecewise linear and their slopes in the passive state(σL>σV)and active state(σL<σV)are similar to that of the consolidationσL-σV relationships in the normal-and over-consolidated states,respectively.The soakingσL-σV relationships converge to the consolidationσL-σV relationships at a thresholdσV where the interparticle swelling is restrained.TheσL0 andσV0 increase monotonically withρd0;however,they show increasing-then-decreasing trends with the w 0.The extent of compaction-induced swelling anisotropy,which is evaluated byσL0/σV0,reduces with an increase in the compaction energy and molding water content.TheσL reduces over moisture cycles and the stress relaxation in theσL during soaking is observed.An approach was developed to predict the at-rest soakingσL-σV relationships,which requires conventional consolidation and shear strength properties and one measurement of theσL-σV relationships during soaking.The proposed approach was validated using the results of three different expansive soils available in the literature. 展开更多
关键词 Lateral earth pressure Expansive soil SOAKING Vertical stress Swelling pressure
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An approach for determination of lateral limit angle in kinematic planar sliding analysis for rock slopes
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作者 Xiaojuan Yang Jie Hu +1 位作者 Honglei Sun Jun Zheng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1305-1314,共10页
Planar sliding is one of the frequently observed types of failure in rock slopes.Kinematic analysis is a classic and widely used method to examine the potential failure modes in rock masses.The accuracy of planar slid... Planar sliding is one of the frequently observed types of failure in rock slopes.Kinematic analysis is a classic and widely used method to examine the potential failure modes in rock masses.The accuracy of planar sliding kinematic analysis is significantly influenced by the value assigned to the lateral limit angleγlim.However,the assignment ofγlim is currently used generally based on an empirical criterion.This study aims to propose an approach for determining the value ofγlim in deterministic and probabilistic kinematic planar sliding analysis.A new perspective is presented to reveal thatγlim essentially influences the probability of forming a potential planar sliding block.The procedure to calculate this probability is introduced using the block theory method.It is found that the probability is correlated with the number of discontinuity sets presented in rock masses.Thus,different values ofγlim for rock masses with different sets of discontinuities are recommended in both probabilistic and deterministic planar sliding kinematic analyses;whereas a fixed value ofγlim is commonly assigned to different types of rock masses in traditional method.Finally,an engineering case was used to compare the proposed and traditional kinematic analysis methods.The error rates of the traditional method vary from 45%to 119%,while that of the proposed method ranges between 1%and 17%.Therefore,it is likely that the proposed method is superior to the traditional one. 展开更多
关键词 Kinematic analysis Block theory Planar sliding Lateral limit angle Rock slope
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Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope
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作者 Wei He Si-yuan Feng +4 位作者 Jian Zhang Hong-wu Tang Yang Xiao Sheng Chen Chun-sheng Liu 《Water Science and Engineering》 EI CAS CSCD 2024年第2期197-208,共12页
Lateral intakes are common in rivers.The pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division width.The hydraulic characteristics of lateral withdrawa... Lateral intakes are common in rivers.The pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division width.The hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be investigated.Meanwhile,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be clarified.Hence,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side bank.The flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel velocities.This study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this phenomenon.The average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank conditions.With a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical direction.Under inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope conditions.The results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains. 展开更多
关键词 Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OPENFOAM
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Analytical model for predicting time-dependent lateral deformation of geosynthetics-reinforced soil walls with modular block facing
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作者 Luqiang Ding Chengzhi Xiao Feilong Cui 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期711-725,共15页
To date,few models are available in the literature to consider the creep behavior of geosynthetics when predicting the lateral deformation(d)of geosynthetics-reinforced soil(GRS)retaining walls.In this study,a general... To date,few models are available in the literature to consider the creep behavior of geosynthetics when predicting the lateral deformation(d)of geosynthetics-reinforced soil(GRS)retaining walls.In this study,a general hyperbolic creep model was first introduced to describe the long-term deformation of geosynthetics,which is a function of elapsed time and two empirical parameters a and b.The conventional creep tests with three different tensile loads(Pr)were conducted on two uniaxial geogrids to determine their creep behavior,as well as the a-Pr and b-Pr relationships.The test results show that increasing Pr accelerates the development of creep deformation for both geogrids.Meanwhile,a and b respectively show exponential and negatively linear relationships with Pr,which were confirmed by abundant experimental data available in other studies.Based on the above creep model and relationships,an accurate and reliable analytical model was then proposed for predicting the time-dependent d of GRS walls with modular block facing,which was further validated using a relevant numerical investigation from the previous literature.Performance evaluation and comparison of the proposed model with six available prediction models were performed.Then a parametric study was carried out to evaluate the effects of wall height,vertical spacing of geogrids,unit weight and internal friction angle of backfills,and factor of safety against pullout on d at the end of construction and 5 years afterwards.The findings show that the creep effect not only promotes d but also raises the elevation of the maximum d along the wall height.Finally,the limitations and application prospects of the proposed model were discussed and analyzed. 展开更多
关键词 GEOSYNTHETICS Creep behavior Geosynthetics-reinforced soil(GRS)walls Lateral deformation Analytical model
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Smart prediction of liquefaction-induced lateral spreading
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作者 Muhammad Nouman Amjad Raja Tarek Abdoun Waleed El-Sekelly 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2310-2325,共16页
The prediction of liquefaction-induced lateral spreading/displacement(Dh)is a challenging task for civil/geotechnical engineers.In this study,a new approach is proposed to predict Dh using gene expression programming(... The prediction of liquefaction-induced lateral spreading/displacement(Dh)is a challenging task for civil/geotechnical engineers.In this study,a new approach is proposed to predict Dh using gene expression programming(GEP).Based on statistical reasoning,individual models were developed for two topographies:free-face and gently sloping ground.Along with a comparison with conventional approaches for predicting the Dh,four additional regression-based soft computing models,i.e.Gaussian process regression(GPR),relevance vector machine(RVM),sequential minimal optimization regression(SMOR),and M5-tree,were developed and compared with the GEP model.The results indicate that the GEP models predict Dh with less bias,as evidenced by the root mean square error(RMSE)and mean absolute error(MAE)for training(i.e.1.092 and 0.815;and 0.643 and 0.526)and for testing(i.e.0.89 and 0.705;and 0.773 and 0.573)in free-face and gently sloping ground topographies,respectively.The overall performance for the free-face topology was ranked as follows:GEP>RVM>M5-tree>GPR>SMOR,with a total score of 40,32,24,15,and 10,respectively.For the gently sloping condition,the performance was ranked as follows:GEP>RVM>GPR>M5-tree>SMOR with a total score of 40,32,21,19,and 8,respectively.Finally,the results of the sensitivity analysis showed that for both free-face and gently sloping ground,the liquefiable layer thickness(T_(15))was the major parameter with percentage deterioration(%D)value of 99.15 and 90.72,respectively. 展开更多
关键词 Lateral spreading Intelligent modeling Gene expression programming(GEP) Closed-form solution Feature importance
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OSMR is a potential driver of inflammation in amyotrophic lateral sclerosis
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作者 Wenzhi Chen Shishi Jiang +2 位作者 Shu Li Cheng Li Renshi Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2513-2521,共9页
Amyotrophic lateral sclerosis is a neurodegenerative disease,and the molecular mechanism underlying its pathology remains poorly understood.However,inflammation is known to play an important role in the development of... Amyotrophic lateral sclerosis is a neurodegenerative disease,and the molecular mechanism underlying its pathology remains poorly understood.However,inflammation is known to play an important role in the development of this condition.To identify driver genes that affect the inflammatory response in amyotrophic lateral sclerosis,as well as potential treatment targets,it is crucial to analyze brain tissue samples from patients with both sporadic amyotrophic lateral sclerosis and C9orf72-related amyotrophic lateral sclerosis.Therefore,in this study we used a network-driven gene analysis tool,NetBID2.0,which is based on SJARACNe,a scalable algorithm for the reconstruction of accurate cellular networks,to experimentally analyze sequencing data from patients with sporadic amyotrophic lateral sclerosis.The results showed that the OSMR gene is pathogenic in amyotrophic lateral sclerosis and participates in the progression of amyotrophic lateral sclerosis by mediating the neuroinflammatory response.Furthermore,there were differences in OSMR activity and expression between patients with sporadic amyotrophic lateral sclerosis and those with C9orf72-related amyotrophic lateral sclerosis.These findings suggest that OSMR may be a diagnostic and prognostic marker for amyotrophic lateral sclerosis. 展开更多
关键词 amyotrophic lateral sclerosis DRIVER NEUROINFLAMMATION OSMR C9ORF72 neurodegenerative disease PATHOGENESIS oxidative stress protein misfolding mitochondrial dysfunction
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Mitophagy in neurodegenerative disease pathogenesis
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作者 Kan Yang Yuqing Yan +7 位作者 Anni Yu Ru Zhang Yuefang Zhang Zilong Qiu Zhengyi Li Qianlong Zhang Shihao Wu Fei Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期998-1005,共8页
Mitochondria are critical cellular energy resources and are central to the life of the neuron.Mitophagy selectively clears damaged or dysfunctional mitochondria through autophagic machinery to maintain mitochondrial q... Mitochondria are critical cellular energy resources and are central to the life of the neuron.Mitophagy selectively clears damaged or dysfunctional mitochondria through autophagic machinery to maintain mitochondrial quality control and homeostasis.Mature neurons are postmitotic and consume substantial energy,thus require highly efficient mitophagy pathways to turn over damaged or dysfunctional mitochondria.Recent evidence indicates that mitophagy is pivotal to the pathogenesis of neurological diseases.However,more work is needed to study mitophagy pathway components as potential therapeutic targets.In this review,we briefly discuss the characteristics of nonselective autophagy and selective autophagy,including ERphagy,aggrephagy,and mitophagy.We then introduce the mechanisms of Parkin-dependent and Parkin-independent mitophagy pathways under physiological conditions.Next,we summarize the diverse repertoire of mitochondrial membrane receptors and phospholipids that mediate mitophagy.Importantly,we review the critical role of mitophagy in the pathogenesis of neurodegenerative diseases including Alzheimer’s disease,Parkinson’s disease,and amyotrophic lateral sclerosis.Last,we discuss recent studies considering mitophagy as a potential therapeutic target for treating neurodegenerative diseases.Together,our review may provide novel views to better understand the roles of mitophagy in neurodegenerative disease pathogenesis. 展开更多
关键词 Alzheimer’s disease amyotrophic lateral sclerosis autophagy mitochondria MITOPHAGY mitophagy receptor PARKIN Parkinson’s disease PINK1
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