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Verification of the Physiological Therapeutic Effects of Harvesting Activities in a Patient with Moderate Alzheimer’s Disease with Long-Term Agricultural Experience
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作者 Kikuo Eguchi Seigo Koura +1 位作者 Nao Eguchi Akihiko Kondou 《Open Journal of Therapy and Rehabilitation》 2024年第3期236-244,共9页
Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting ac... Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting activities as a part of their treatment. The patients became calmer and began to smile not only after but also before and during harvesting activity. Therefore, this study aimed to measure autonomic nervous system (ANS) responses over time in a female patient in her 80s with moderate Alzheimer’s disease (AD) who had experience in farming when performing harvesting activities. Additionally, this study aimed to consider factors associated with changes in ANS responses over time and to verify the physiological therapeutic effects of harvesting activities. Methods: An OT with more than 10 years of experience and a good relationship with the patient conducted one-on-one sessions with the patient. Harvesting activity was performed in a courtyard with trees. The patient harvested lettuce (three lettuce plants) grown in a planter while sitting on a chair. Additionally, the planter was set up on a desk. ANS responses were measured over time from before to after the activity for different events at six time periods. Changes in the patient’s ANS responses were assessed during each period. Results: With the involvement of environmental factors and OT during harvesting activities, parasympathetic nervous system (PNS) activity significantly increased. This may lead to improved mental stability. Conclusion: The findings of this study indicate that implementing harvesting activities may have a positive effect on the PNS in patients with AD with long-term agricultural experience. However, further studies with a larger sample size and multidimensional evaluations are needed. 展开更多
关键词 Alzheimer’s Disease Autonomic Nervous Response Harvesting Activity Therapeutic effects
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Effect of stress on microstructures of creep-aged 2524 alloy 被引量:3
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作者 权力伟 赵刚 +1 位作者 田妮 黄明丽 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2209-2214,共6页
Microstructures of creep-aged 2524 (A1-4.3Cu-1.5Mg) aged at 170 ℃ with various stresses (0, 173 and 250 MPa) were studied on a creep machine. Ageing hardness curves under various stresses were plotted and the cor... Microstructures of creep-aged 2524 (A1-4.3Cu-1.5Mg) aged at 170 ℃ with various stresses (0, 173 and 250 MPa) were studied on a creep machine. Ageing hardness curves under various stresses were plotted and the corresponding microstructures were characterized by transmission electron microscopy (TEM). The results show that the value of peak hardness is increased, while the time to reach the peak hardness is reduced under an external stress. Meanwhile, the length of S(Al2CuMg) phase is shorter and the number density of S phases is larger in the creep-aged alloy. The predominant contribution to the peak hardness can be ascribed to the GPB zones with an elastic stress. 展开更多
关键词 creep-age s phase GPB zone hardness DIsLOCATION stress orientation effect
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甘肃积石山 M_(s)6.2级地震的震害特征与启示 被引量:6
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作者 王丽丽 王兰民 +5 位作者 卢育霞 许世阳 夏晓雨 盖海龙 池佩红 郭梅 《世界地震工程》 北大核心 2024年第1期58-71,共14页
2023年12月18日,甘肃省临夏回族自治州积石山保安族东乡族撒拉族自治县(35.70°N,102.79°E)发生了6.2级地震,震中烈度为VIII度。地震发生后,通过实地烈度评估与科学考察,对震区VI~VIII度区不同建(构)筑物与生命线工程的震害特... 2023年12月18日,甘肃省临夏回族自治州积石山保安族东乡族撒拉族自治县(35.70°N,102.79°E)发生了6.2级地震,震中烈度为VIII度。地震发生后,通过实地烈度评估与科学考察,对震区VI~VIII度区不同建(构)筑物与生命线工程的震害特点进行了统计分析;从抗震设计与施工管理、场地放大效应与地震次生灾害对建筑结构抗震性能的影响等角度,提出了此次地震的震害启示。结果表明:1)严重破坏和毁坏的建筑结构主要集中在老旧的土木结构、砖木结构和无设防或设防不规范的砖混结构。2)造成建筑结构破坏的主要原因是少量自建房抗震设计和施工的不规范、场地放大效应和地震次生灾害。3)优化和改良生土砌筑材料,改进纵横墙间的拉结措施,强化结构整体性是提高土木结构抗震的有效方法;普及“上下圈梁与构造柱”等基本抗震设防措施,规范水泥砂浆强度,提升农村工匠的施工水平,可有效提高砌体结构的整体性,避免房屋出现整体性垮塌;室内洗手间的墙体应该与房顶、纵横墙间建立有效联接,提高结构的抗震性能。4)孤突斜坡、河流高阶地与岸边为抗震不利地带。当建造用地极为匮乏,不得不选址在这些场地之上时,应该综合考虑场地的地形地貌特征、岩土体物理力学特性、水文地质条件、抗震设防目标、建筑结构类型等影响因素,做好地震灾害风险评估,根据评估结果进行科学设防。灾后重建过程中,应由政府统一规划选址、统一设计,规范施工。 展开更多
关键词 积石山6.2级地震 震害调查 场地放大效应 黄土液化流滑 震害特征
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Pretreatment with Rhodiola Rosea Extract Reduces Cognitive Impairment Induced by Intracerebroventricular Streptozotocin in Rats: Implication of Anti-oxidative and Neuroprotective Effects 被引量:15
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作者 PETER CHUNG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第4期318-326,共9页
Objective To investigate the pretreatment effects of Rhodiola rosea (R. rosea) extract on cognitive dysfunction, oxidative stress in hippocampus and hippocampal neuron injury in a rat model of Alzheimer's disease ... Objective To investigate the pretreatment effects of Rhodiola rosea (R. rosea) extract on cognitive dysfunction, oxidative stress in hippocampus and hippocampal neuron injury in a rat model of Alzheimer's disease (AD). Methods Male Sprague-Dawley rats were pretreated with R. rosea extract at doses of 1.5, 3.0, and 6.0 g/kg for 3 weeks, followed by bilateral intracerebroventricular injection with streptozotocin (1.5 mg/kg) on days 1 and 3. Behavioral alterations were monitored after 2 weeks from the lesion using Morris water maze task. Three weeks after the lesion, the rats were sacrificed for measuring the malondialdehyde (MDA), glutathione reductase (GR) and reduced glutathione (GSH) levels in hippocampus and histopathology of hippocampal neurons. Results The MDA level was significantly increased while the GR and GSH levels were significantly decreased with striking impairments in spatial learning and memory and severe damage to hippocampal neurons in the model rat induced by intracerebroventricular injection of streptozotocin. These abnormalities were significantly improved by pretreatment with R. rosea extract (3.0 g/kg). Conclusion R. rosea extract can protect rats against cognitive deficits, neuronal injury and oxidative stress induced by intracerebroventricular injection of streptozotocin, and may be used as a potential agent in treatment of neurodegenerative diseases such as AD. 展开更多
关键词 Rhodiola rosea Oxidative stress Neuroprotective effect Learning and memory Alzheimer's disease Intracerebroventricular streptozotocin
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Effect of Friedel's salt on strength enhancement of stabilized chloride saline soil 被引量:6
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作者 CHENG Yin LI Zhan-guo +1 位作者 HUANG Xin BAI Xiao-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期937-946,共10页
In the field of soil stabilization, only calcium silicate hydrate(CSH) and ettringite(AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fi... In the field of soil stabilization, only calcium silicate hydrate(CSH) and ettringite(AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fill, an artificial chloride saline soil, and a non-saline soil were stabilized by Portland cement(PC) and PC with Ca(OH)_2(CH) with different contents. A series of unconfined compressive strength(UCS) tests of stabilized soil specimen after curing for 7 d and 28 d were carried out, and the hydration products and microstructure of the specimens were observed by X-ray diffractometry(XRD), scanning electronic microscopy(SEM), and energy-dispersive X-ray analysis(EDXA). The results showed that the strengths of PC+CH-stabilized chloride saline soils were much higher than those of PC-stabilized soils. A new hydration product of calcium aluminate chloride hydrate, also known as Friedel's salt, appeared in the PC+CH-stabilized chloride saline soils. The solid-phase volume of Friedel's salt expanded during the formation of the hydrate; this volume filled the pores in the stabilized soil. This pore-filling effect was the most important contribution to the significantly enhanced strength of the PC+CH-stabilized chloride saline soils. On the basis of this understanding, a new optimized stabilizer was designed according to the concept that the chloride in saline soil could be utilized as a component of the stabilizer. The strength of the chloride saline soils stabilized by the optimized stabilizer was even further increased compared with that of the PC+CH-stabilized soils. 展开更多
关键词 CHLORIDE sALINE sOIL sTABILIZED sOIL Friedel’s sALT strength enhancement effect
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Lactoferrin modification of berberine nanoliposomes enhances the neuroprotective effects in a mouse model of Alzheimer’s disease 被引量:7
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作者 Lin Wang Bi-Qiang Zhou +5 位作者 Ying-Hong Li Qian-Qian Jiang Wei-Hong Cong Ke-Ji Chen Xiao-Min Wen Zheng-Zhi Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第1期226-232,共7页
Previous studies have shown that berberine has neuroprotective effects against Alzheimer’s disease,including antagonizing tau phosphorylation,and inhibiting acetylcholinesterase activity and neural cell apoptosis.How... Previous studies have shown that berberine has neuroprotective effects against Alzheimer’s disease,including antagonizing tau phosphorylation,and inhibiting acetylcholinesterase activity and neural cell apoptosis.However,its low bioavailability and adverse reactions with conventional administration limit its clinical application.In this study,we prepared berberine nanoliposomes using liposomes characterized by low toxicity,high entrapment efficiency,and biodegradability,and modified them with lactoferrin.Lactoferrin-modified berberine nanoliposomes had uniform particle size and high entrapment efficiency.We used the lactoferrin-modified berberine nanoliposomes to treat a mouse model of Alzheimer’s disease established by injection of amyloid-beta 1-42 into the lateral ventricle.Lactoferrin-modified berberine nanoliposomes inhibited acetylcholinesterase activity and apoptosis in the hippocampus,reduced tau over-phosphorylation in the cerebral cortex,and improved mouse behavior.These findings suggest that modification with lactoferrin can enhance the neuroprotective effects of berberine nanoliposomes in Alzheimer’s disease. 展开更多
关键词 ACETYLCHOLINEsTERAsE Alzheimer’s disease apoptosis BERBERINE brain targeting LACTOFERRIN NANOLIPOsOMEs neuroprotective effects Tau phosphorylation
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Surface-effects-dominated thermal and mechanical responses of zinc oxide nanobelts 被引量:6
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作者 A. J. Kulkarni. M. Zhou 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第3期217-224,共8页
t Molecular dynamics (MD) simulations are carried out to characterize the mechanical and thermal responses of [011^-1]-oriented ZnO nanobelts with lateral dimensions of 21.22A × 18.95 A, 31.02A× 29.42 A, a... t Molecular dynamics (MD) simulations are carried out to characterize the mechanical and thermal responses of [011^-1]-oriented ZnO nanobelts with lateral dimensions of 21.22A × 18.95 A, 31.02A× 29.42 A, and40.81A ×39.89A over the temperature range of 300-1000 K. The Young's modulus and thermal conductivity of the nanobelts are evaluated. Significant surface effects on properties due to the highsurface-to-volume ratios of the nanobelts are observed. For the mechanical response, surface-stress-induced internal stress plays an important role. For the thermal response, surface scattering of phonons dominates. Calculations show that the Young's modulus is higher than the corresponding value for bulk ZnO and decreases by -33% as the lateral dimensions increase from 21.22 A × 18.95A to 40.81 A × 39.89A. The thermal conductivity is one order of magnitude lower than the corresponding value for bulk ZnO single crystal and decreases with wire size. Specifically, the conductivity of the 21.22 A × 18.95 A belt is approximately (31-18)% lower than that of the 40.81 A × 39.89 A belt over the temperature range analyzed. A significant dependence of properties on temperature is also observed, with the Young's modulus decreasing on average by 12% and the conductivity decreasing by 50% as temperature increases from 300 K to 1000 K. 展开更多
关键词 Zinc oxide nanobelts surface effects size dependence Young's modulus Thermal conductivity
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RELATIVE SEA LEVEL RISE AND ITS EFFECTS ON ENVIRONMENT AND RESOURCES IN CHINAS COASTAL AREAS 被引量:2
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作者 杨桂山 《Chinese Geographical Science》 SCIE CSCD 1995年第2期104-115,共12页
Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21... Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21st century. It will result in a series of adverse impacts on evolution of natural environment and socioeconomic development of the coastal area. This paper analyses environmental and resource effects induced by relative sea level rise in China's coastal areas on the basis of rough estimate of future relative sea level rise. These effects include inundating tidal flat and wetlands and increase in inundated risk of coastal habitable land,exacerbating storm surge. coastal erosion, flooding and salt water intrusion hazards.as well as endangering land. water. tourism and living resources and their utilization. 展开更多
关键词 China’s COAsTAL areas. RELATIVE sEA LEVEL RIsE environmental effect resource effect
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Anti-Parkinsonian Therapy:Strategies for Crossing the Blood–Brain Barrier and Nano-Biological Effects of Nanomaterials 被引量:3
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作者 Guowang Cheng Yujing Liu +5 位作者 Rui Ma Guopan Cheng Yucheng Guan Xiaojia Chen Zhenfeng Wu Tongkai Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第6期350-398,共49页
Parkinson’s disease(PD),a neurodegenerative disease that shows a high incidence in older individuals,is becoming increasingly prevalent.Unfortunately,there is no clinical cure for PD,and novel anti-PD drugs are there... Parkinson’s disease(PD),a neurodegenerative disease that shows a high incidence in older individuals,is becoming increasingly prevalent.Unfortunately,there is no clinical cure for PD,and novel anti-PD drugs are therefore urgently required.However,the selective permeability of the blood–brain barrier(BBB)poses a huge challenge in the development of such drugs.Fortunately,through strategies based on the physiological characteristics of the BBB and other modifications,including enhancement of BBB permeability,nanotechnology can offer a solution to this problem and facilitate drug delivery across the BBB.Although nanomaterials are often used as carriers for PD treatment,their biological activity is ignored.Several studies in recent years have shown that nanomaterials can improve PD symptoms via their own nano-bio effects.In this review,we first summarize the physiological features of the BBB and then discuss the design of appropriate brain-targeted delivery nanoplatforms for PD treatment.Subsequently,we highlight the emerging strategies for crossing the BBB and the development of novel nanomaterials with anti-PD nano-biological effects.Finally,we discuss the current challenges in nanomaterial-based PD treatment and the future trends in this field.Our review emphasizes the clinical value of nanotechnology in PD treatment based on recent patents and could guide researchers working in this area in the future. 展开更多
关键词 Blood-brain barrier Parkinson’s disease Nasal delivery Biomimetic drug delivery Nano-biological effects
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Magnesium-L-threonate exhibited a neuroprotective effect against oxidative stress damage in HT22 cells and Alzheimer’s disease mouse model 被引量:3
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作者 Ying Xiong Yu-Ting Ruan +8 位作者 Jing Zhao Yu-Wen Yang Li-Ping Chen Ying-Ren Mai Qun Yu Zhi-Yu Cao Fei-Fei Liu Wang Liao Jun Liu 《World Journal of Psychiatry》 SCIE 2022年第3期410-424,共15页
BACKGROUND Oxidative stress results in the production of excess reactive oxygen species(ROS)and triggers hippocampal neuronal damage as well as occupies a key role in the pathological mechanisms of neurodegenerative d... BACKGROUND Oxidative stress results in the production of excess reactive oxygen species(ROS)and triggers hippocampal neuronal damage as well as occupies a key role in the pathological mechanisms of neurodegenerative disorders such as Alzheimer’s disease(AD).A recent study confirmed that magnesium had an inhibitory effect against oxidative stress-related malondialdehyde in vitro.However,whether Magnesium-L-threonate(MgT)is capable of suppressing oxidative stress damage in amyloidβ(Aβ)_(25-35)-treated HT22 cells and the AD mouse model still remains to be investigated.AIM To explore the neuroprotective effect of MgT against oxidative stress injury in vitro and in vivo,and investigate the mechanism.METHODS Aβ_(25-35)-induced HT22 cells were preconditioned with MgT for 12 h.APPswe/PS1dE9(APP/PS1)mice were orally administered with MgT daily for 3 mo.After MgT treatment,the viability of Aβ_(25-35)-treated HT22 cells was determined via conducting cell counting kit-8 test and the cognition of APP/PS1 mice was measured through the Morris Water Maze.Flow cytometry experiments were applied to assess the ROS levels of HT22 cells and measure the apoptosis rate of HT22 cells or hippocampal neurons.Expression of B-cell lymphoma 2(Bcl-2),Bcl-2-associated X(Bax),hypoxiainducible factor(HIF)-1α,NADPH oxidase(NOX)4,Aβ_(1-42) and phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt)pathway proteins was quantified by Western blot.RESULTS In vitro data confirmed that Aβ_(25-35)-induced HT22 cells had a significantly lower cell viability,higher ROS level and higher apoptosis rates compared with those of control cells(all P<0.001).MgT prevented the Aβ_(25-35)-triggered oxidative stress damage by elevating viability and decreasing ROS formation and apoptosis of HT22 cells(all P<0.001).APP/PS1 mice exhibited worse cognitive performance and higher apoptosis rate of hippocampal neurons than wild-type(WT)mice(all P<0.01).Meanwhile,significant higher expression of Aβ_(1-42) and NOX4 proteins was detected in APP/PS1 mice than those of WT mice(both P<0.01).MgT also ameliorated the cognitive deficit,suppressed the apoptosis of hippocampal neuron and downregulated the expression of Aβ_(1-42) and NOX4 proteins in APP/PS1 mouse(all P<0.05).Moreover,MgT intervention significantly downregulated HIF-1αand Bax,upregulated Bcl-2 and activated the PI3K/Akt pathway both in vitro and in vivo(all P<0.05).CONCLUSION MgT exhibits neuroprotective effects against oxidative stress and hippocampal neuronal apoptosis in Aβ_(25-35)-treated HT22 cells and APP/PS1 mice. 展开更多
关键词 Alzheimer’s disease MAGNEsIUM Neuroprotective effect Oxidative stress HIPPOCAMPAL Neuronal apoptosis
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A novel binary effective medium model to describe the prepeak stressstrain relationship of combined bodies of rock-like material and rock 被引量:2
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作者 Tienan Wang Yue Zhai +2 位作者 Huan Gao Yubai Li Ruifeng Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第5期601-616,共16页
Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body ... Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body lack a binary feature.Based on effective medium theory,this paper presents the governing equation of the“elastic modulus”for combined and single bodies under triaxial compressive tests.A binary effective medium model is then established.Based on the compressive experiment of concretegranite combined bodies,the feasibility of determining the stress threshold based on crack axial strain is discussed,and the model is verified.The model is further extended to coal-rock combined bodies of more diverse types,and the variation laws of the compressive mechanical parameters are then discussed.The results show that the fitting accuracy of the model with the experimental curves of the concretegranite combined bodies and various types of coal-rock combined bodies are over 95%.The crack axial strain method can replace the crack volumetric strain method,which clarifies the physical meanings of the model parameters.The variation laws of matrix parameters and crack parameters are discussed in depth and are expected to be more widely used in geotechnical engineering. 展开更多
关键词 Combined body stress-strain relationship Hooke’s law effective medium theory stress threshold determination
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ELECTRIC FIELD EFFECTS ON YOUNG'S MOLULUS OF NANOWIRES 被引量:2
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作者 Xiaojing Zheng Li Qiao 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第6期511-523,共13页
As an important component of nanodevices and nanomachine constructions, the mechanical performance of nanowires (NWs) has been a subject of intense research efforts due to gaining relevance in controlling functional... As an important component of nanodevices and nanomachine constructions, the mechanical performance of nanowires (NWs) has been a subject of intense research efforts due to gaining relevance in controlling functionality of nanoelectromechanical systems (NEMS); meanwhile, one of the characteristics of the NEMS is the dependence of the functionality of the systems upon the applied electric field. The study of the electric effects on the Young's modulus of nanostructures is of certain usefulness in the design of NEMS and the precise measurement of mechanical properties of one-dimensional nanostructures. This paper reviews the origin of the size-dependence of the elastic property of NWs and the factors influencing the discrepancies and inconsistencies in the measured values of the Young's modulus for the NW, besides the surface effects, nonlinear effects, the electromechanical coupling effects as a possible effect responsible for the differences in quantitative and qualitative performance of the measured Young's modulus for the NWs versus the diameter are clarified. 展开更多
关键词 NANOWIREs Young's modulus molecular dynamics simulations continuum mechanics theory electric effects
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Contribution to the understanding effects of weak electrical phenomena 被引量:1
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作者 Józef Mazurkiewicz Piotr Tomasik 《Natural Science》 2010年第11期1195-1210,共16页
Electronic emission spectra of N2, (N2)2, (N2)5 O2, (O2)2, (O2)5, H2O, (H2O)5, CO2, (CO2)2, CO2..H2O, NH3 and NH3.H2O situated in the electric field of 0.001, 0.005, 0.01 0.05 and 0.1 a.u. were simulated involving Mon... Electronic emission spectra of N2, (N2)2, (N2)5 O2, (O2)2, (O2)5, H2O, (H2O)5, CO2, (CO2)2, CO2..H2O, NH3 and NH3.H2O situated in the electric field of 0.001, 0.005, 0.01 0.05 and 0.1 a.u. were simulated involving Monte Carlo optimization followed by the ZINDO/S approach. The simulated spectra showed irregular dependence on the energy of the electric field applied. Molecules without influence of the electric field emit in the vacuum ultraviolet region. Applied electric field only in case of (O2)5 generated transitions above 200 nm. The mapping of isosurface of the investigated molecules revealed that the electric field applied redistributed the charge densities in the molecules in the manner approximately parallel to the energy of the field. Applied electrical field resulted in an increase in the water acidity and ammonia basicity. 展开更多
关键词 Electronic EMIssION sPECTRA surface effect ZINDO/s sPECTRA simulations
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Analytical solutions for constant-rate test in bounded confined aquifers with non-Darcian effect 被引量:2
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作者 Yi-jie Zong Li-hua Chen +4 位作者 Jian-jun Liu Yue-hui Liu Yong-xin Xu Fu-wan Gan Liang Xiao 《Journal of Groundwater Science and Engineering》 2022年第4期311-321,共11页
This paper proposes a simplified analytical solution considering non-Darcian and wellbore storage effect to investigate the pumping flow in a confined aquifer with barrier and recharge boundaries.The mathematical mode... This paper proposes a simplified analytical solution considering non-Darcian and wellbore storage effect to investigate the pumping flow in a confined aquifer with barrier and recharge boundaries.The mathematical modelling for the pumping-induced flow in aquifers with different boundaries is developed by employing image-well theory with the superposition principle,of which the non-Darcian effect is characterized by Izbash’s equation.The solutions are derived by Boltzmann and dimensionless transformations.Then,the non-Darcian effect and wellbore storage are especially investigated according to the proposed solution.The results show that the aquifer boundaries have non-negligible effects on pumping,and ignoring the wellbore storage can lead to an over-estimation of the drawdown in the first 10 minutes of pumping.The higher the degree of non-Darcian,the smaller the drawdown. 展开更多
关键词 Non-Darcian effect Bounded aquifer Wellbore storage Izbash’s equation Analytical solution
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First-principles investigation of electronic structure,effective carrier masses, and optical properties of ferromagnetic semiconductor CdCr_2S_4 被引量:1
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作者 朱旭辉 陈向荣 刘邦贵 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第5期346-351,共6页
The electronic structures, the effective masses, and optical properties of spinel CdCr_2S_4 are studied by using the fullpotential linearized augmented planewave method and a modified Becke–Johnson exchange functiona... The electronic structures, the effective masses, and optical properties of spinel CdCr_2S_4 are studied by using the fullpotential linearized augmented planewave method and a modified Becke–Johnson exchange functional within the densityfunctional theory. Most importantly, the effects of the spin–orbit coupling(SOC) on the electronic structures and carrier effective masses are investigated. The calculated band structure shows a direct band gap. The electronic effective mass and the hole effective mass are analytically determined by reproducing the calculated band structures near the BZ center.SOC substantially changes the valence band top and the hole effective masses. In addition, we calculated the corresponding optical properties of the spinel structure CdCr_2S_4. These should be useful to deeply understand spinel CdCr_2S_4 as a ferromagnetic semiconductor for possible semiconductor spintronic applications. 展开更多
关键词 CdCr2s4 semiconductor effective mass optical properties density functional theory
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Effects of natural-cerebrolysin-containing serum on neurotoxicity and synaptogenesis in amyloid-beta 1-40-induced Alzheimer's disease in vitro models 被引量:1
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作者 Yinghong Li Zhengzhi Wu +3 位作者 Andrew C. J. HuangO Ming Li XiaoLi Zhang Jiguo Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第2期85-91,共7页
BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, an... BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, and dendritic generation, extension, and stabilization, as well as for the regulation of synaptic plasticity. OBJECTIVE: To investigate the antagonistic effects of natural-cerebrolysin-containing serum on beta amyloid protein 1-40 (Aβ1-40)-induced neurotoxicity from the standpoints of cell proliferation, synaptogenesis, and cytoskeleton formation (MAP2 expression). DESIGN, TIME AND SETTING: A paralleled, controlled, neural cell, and molecular biology experiment was performed at the Institute of Integrated Chinese and Western Medicine, Shenzhen Hospital, Southern Medical University between February 2006 and April 2008. MATERIALS: PC12 cells, derived from the rat central nervous system, were purchased from Shanghai Institute of Cell Biology, Chinese Academy of Sciences, China. A β1-40 was provided by Sigma, USA. Natural-cerebrolysin was provided by Shenzhen Institute of Integrated Chinese and Western Medicine, China. The natural-cerebrolysin was predominantly composed of Renshen (Radix Ginseng), Tianma (Rhizoma Gastrodiae), and Yixingye (Ginkgo Leaf) in a proportion of 1:2:2. Following conventional water extraction technology, an extract (1:20) was prepared. Each gram of extract equaled 20 grams of crude drug. In a total of 12 adult male New Zealand rabbits, six underwent intragastric administration of natural-cerebrolysin extract for 1 month to prepare natural-cerebrolysin-containing serum, and the remaining six rabbits received intragastric administration of physiological saline to prepare normal blank serum. METHODS: An AIzheimer's disease in vitro model was induced in PC12 cells using Aβ1-40. The cells were incubated with varying doses of natural-cerebrolysin-containing serum (2.5%, 5%, and 10%). Normal blank serum-treated PC12 cells served as a blank control group. MAIN OUTCOME MEASURES: Through the use of inverted phase contrast microscope, cell morphology and neurite growth were observed, neurite length was measured, and the percentage of neurite-positive cells was calculated. Cell proliferation rate was determined by MTT assay, and MAP 2 expression was detected by fluorescent immunocytochemistry. RESULTS: Following Aβ1-40 treatments, some PC12 cells were apoptotic/dying, and only a few short neurites were observed. Following interventions with natural-cerebrolysin-containing serum, the PC12 cells proliferated, there was an increased number of neurites, and neurite length was enhanced. After middle- and high-dose natural-cerebrolysin treatments, the percentage of neurite-positive cells, as well as the average length of neurites, was significantly greater than the normal blank serum-treated PC12 cells (P 〈 0.05 or P 〈 0.01). Compared with the blank control group, MAP2 expression in the Aβ1-40-treated PC12 cells was significantly inhibited, and the cell proliferation rate was significantly decreased (P 〈 0.01). Following incubations with natural-cerebrolysin-containing serum, MAP2 expression and cell proliferation rate in the PC12 cells were significantly increased in a dose-dependent manner, compared with treatments with blank control serum (P 〈 0.05 or P 〈 0.01 ). CONCLUSION: Natural-cerebrolysin exhibited antagonistic effects on neurotoxicity in Aβ1-40 induced Alzheimer's disease in vitro models. These effects were likely related to cell proliferation and the upregulation of intracellular MAP2 expression. 展开更多
关键词 natural-cerebrolysin Alzheimer's disease in vitro model NEUROTOXICITY neuroprotective effect amyloid beta protein 1-40
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Effects of Streptomyces <i>Biofertilizer</i>to Soil Fertility and Rhizosphere’s Functional Biodiversity of Agricultural Plants 被引量:3
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作者 Tinatin Doolotkeldieva Saykal Bobusheva Maxabat Konurbaeva 《Advances in Microbiology》 2015年第7期555-571,共17页
In the present study, a biofertilizer on the basis of Streptomyces fumanus gn-2 was used for the treatment of wheat and soybean seeds (dose 104 spore/ml) before planting them in soil with low fertility in order to det... In the present study, a biofertilizer on the basis of Streptomyces fumanus gn-2 was used for the treatment of wheat and soybean seeds (dose 104 spore/ml) before planting them in soil with low fertility in order to determine the effect of this biological agent on germination rate;the growth of seedlings, shoots, and the maturation phase of plants;the rhizosphere’s functional biodiversity;and the resistance of these plants to pathogens. Seeds were soaked in the suspension for a period of two or three hours. During the growing season of the crop, no additional fertilizing and spraying of a biopesticide against diseases or pests occurred. Despite the soil having low fertility, low quantities of organic matter, and not having been before used for the cultivation of agricultural plants, this biofertilizer showed a strong stimulatory effect on the growth of seeds and seedlings of wheat and soybeans. The average germination and seed vigor increased by 1.5 - 2.0 times, and the phenophases were accelerated to three to five days. In all phases of vegetation, the ammonifying bacteria in the presence of an antagonist (a biological agent) developed rapidly and were constantly present in significant numbers in the rhizosphere. Streptomyces fumanus introduced into non-sterile soil entered into competition with the local soil microflora and had the ability to colonize the rhizosphere system of plants. The use of a formulation of Streptomyces gn-2 has improved the composition of rhizosphere microflora, attracting saprophytic microorganisms: ammonificators and oligotrophs. The presence of the biocontrol microorganism Streptomyces fumanus in the rhizosphere plays an important role in enhancing the growth and development of useful groups, such as nitrogen-fixing bacteria. 展开更多
关键词 A Low Fertility soil A BIOFERTILIZER streptomyces fumanus gn-2 Wheat and soybean seeds stimulatory effect on seed Germination Rhizosphere’s FUNCTIONAL BIODIVERsITY
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Effects of natural cerebrolysin on protective proteins and pro-apoptotic molecules in mesenchymal stem cells following beta-amyloid peptide1-40-induced endoplasmic reticulum stress 被引量:1
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作者 Yinghong Li Zhengzhi Wu +4 位作者 Ming Li Xiaoli Zhang Min Yang Manyin Chen Andrew C. J.Huang O 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第12期986-993,共8页
BACKGROUND: Studies have demonstrated that β-amyloid peptide (Aβ), a characteristic pathological product of Alzheimer's disease (AD), results in neuronal endoplasmic reticulum stress (ERS). However, the mech... BACKGROUND: Studies have demonstrated that β-amyloid peptide (Aβ), a characteristic pathological product of Alzheimer's disease (AD), results in neuronal endoplasmic reticulum stress (ERS). However, the mechanisms of traditional Chinese medicine against ERS in AD are poorly understood. OBJECTIVE: To measure expression levels of protective proteins (GRP78 and GRP94) of ER molecular partners and pro-apoptotic Caspase-12 ER membrane expression following application of traditional Chinese medicine natural cerebrolysin (NC) to treat Aβ1-40-induced ERS. DESIGN, TIME AND SETTING: A parallel-controlled study was performed at the Institute of Integrated Western and Traditional Chinese Medicine, Shenzhen Hospital of Southern Medical University between September 2006 and November 2008. MATERIALS: Sprague Dawley male rats, 6-8 weeks old, were used to harvest tibial and femoral bone marrow. Isolation and purification of mesenchymal stem cells (MSCs) were established from the whole bone marrow by removing non-adherent cells in primary and passage cultures. Aβ1-40 was provided by Sigma, USA. NC was provided by Shenzhen Institute of Integrated Chinese and Western Medicine, China. NC was predominantly composed of Renshen (Radix Ginseng), Tianma (Rhizoma Gastrodiae), and Yinxingye (Ginkgo Leaf) in a proportion of 1 : 2: 2. Following conventional water extraction technology, an extract (1 : 20) was prepared. Six adult, male, New Zealand rabbits underwent intragastric administration of NC extract (0.976 g/kg per day) for 1 month to prepare NC-positive serum, and the remaining 6 rabbits received intragastric administration of physiological saline to prepare normal blank serum. METHODS: A total of 500 nmol/L Aβ1-40 was used to establish ERS models of primary cultured MSCs. AD cell models were incubated with different doses of NC-positive serum (2.5%, 5%, and 10%). MSCs treated with normal blank serum served as normal blank controls. MAIN OUTCOME MEASURES: Reverse transcription-polymerase chain reaction and fluorescent immunocytochemistry were respectively used to measure mRNA and protein expression levels of GRP78, GRP94, and Caspase-12 in MSCs. RESULTS: Following Aβ1-40 exposure, mRNA and protein expression levels of GRP78 and GRP94, as well as Caspase-12, significantly increased (P 〈 0.05), suggesting successful establishment of ERS models. Following NC-positive serum application, mRNA and protein expression levels of GRP78 and GRP94 in MSCs significantly increased (P 〈 0.05 or P 〈 0.01). However, mRNA and protein expression levels of Caspase-12 significantly decreased (P 〈 0.05, or P 〈 0.01) compared with the ERS model group. These effects were dose-dependent. CONCLUSION: NC downregulated Caspase-12 expression and upregulated GRP78 and GRP94 expression in MSCs in a dose-dependent manner under the state of Aβ1-40-induced ERS. 展开更多
关键词 endoplasmic reticulum stress amyloid beta protein 1-40 Alzheimer's Disease natural cerebrolysin protective effect mesenchymal stem cells
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Study on the Antitumor Effects of Low-energy Laser Irradiation Combined with Cyclophosphamide 被引量:1
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作者 HUANGBao-xu WANGHong-bin +3 位作者 QUZhi-na LIUHuan-qi LIUXi-feng CHENGShao-hui 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第1期43-48,共6页
Systematic experiments about the antitumor effects of low energy laser irradiation combined with the traditional antitumor medicine of cyclophosphamide were conducted using the experimental model of mouse S180 ascite... Systematic experiments about the antitumor effects of low energy laser irradiation combined with the traditional antitumor medicine of cyclophosphamide were conducted using the experimental model of mouse S180 ascites sarcoma.The three groups of tumor bearing mice were irradiated upon the inner corners with the dosages of 11 00,14 67 and 22 00 J·cm -2 LELI respectively,and injected with CYT intraperitoneally to observe the changes of the survival time,the ascites growth speed,and the kinetic changes of immune functions.The survival times of the three groups of CYT/LELI combination were obviously longer than those of the tumor and CYT control groups.Correspondingly,the amounts of ascites,tumor cells densities and total tumor cells in CYT/LELI groups decreased significantly,while the death ratio of the tumor cells increased.Comparatively,the group of 22 00 J·cm -2 LELI combined with CYT showed the most ideal antitumor effects,and the life prolongation ratio was up to 53 20%. 展开更多
关键词 Low energy laser irradiation (LELI) cyclophosphamide(CYT) antitumor effects mouse s180 ascites sarcoma
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Neuroprotective effect of the Chinese medicine Tiantai No.1 and its molecular mechanism in the senescence-accelerated mouse prone 8 被引量:4
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作者 Ying-hong Li Xu-sheng Wang +5 位作者 Xiao-lin Chen Yu Jin Hong-bo Chen Xiu-qin Jia Yong-feng Zhang Zheng-zhi Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第2期301-306,共6页
Tiantai No.1, a Chinese medicine predominantly composed of powdered Rhizoma Gastrodiae, Radix Ginseng, and Ginkgo leaf at a ratio of 2:1:2 and dissolved in pure water, is neuroprotective in animal models of various ... Tiantai No.1, a Chinese medicine predominantly composed of powdered Rhizoma Gastrodiae, Radix Ginseng, and Ginkgo leaf at a ratio of 2:1:2 and dissolved in pure water, is neuroprotective in animal models of various cognitive disorders, but its molecular mechanism remains unclear. We administered Tiantai No.1 intragastrically to senescence-accelerated mouse prone 8(SAMP8) mice(a model of Alzheimer's disease) at doses of 50, 100 or 150 mg/kg per day for 8 weeks and evaluated their behavior in the Morris water maze and expression of Alzheimer's disease-related proteins in the brain. Tiantai No.1 shortened the escape latency in the water maze training trials, and increased swimming time in the target quadrant during the spatial probe test, indicating that Tiantai No.1 improved learning and memory in SAMP8 mice. Immunohistochemistry revealed that Tiantai No.1 restored the proliferation potential of Ki67-positive cells in the hippocampus. In addition, mice that had received Tiantai No.1 had fewer astrocytes, and less accumulation of amyloid-beta and phosphorylated tau. These results suggest that Tiantai No.1 is neuroprotective in the SAMP8 mouse model of Alzheimer's disease and acts by restoring neuronal number and proliferation potential in the hippocampus, decreasing astrocyte infiltration, and reducing the accumulation of amyloid-beta and phosphorylated tau. 展开更多
关键词 nerve regeneration neuroprotective effects Alzheimer's disease Tiantai No.1 sAMP8 amyloid-beta autophagy-lysosome pathway ubiquitin proteasome pathway tau phosphorylation neuronal apoptosis astrocytosis neural regeneration
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