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Assessing the Impacts of Land Use and Land Cover Changes on Hydrology of the Mbarali River Sub-Catchment. The Case of Upper Great Ruaha Sub-Basin, Tanzania 被引量:1
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作者 Edmund Mutayoba Japhet J. Kashaigili +2 位作者 Frederick C. Kahimba Winfred Mbungu Nyemo A. Chilagane 《Engineering(科研)》 2018年第9期616-635,共20页
Intensification of agricultural land use and population growth from 1990-2017 has caused changes in land cover and land use of the Mbarali River sub-catchment which is located in the Upper Great Ruaha Sub basin, Tanza... Intensification of agricultural land use and population growth from 1990-2017 has caused changes in land cover and land use of the Mbarali River sub-catchment which is located in the Upper Great Ruaha Sub basin, Tanzania. This has affected the magnitude of the surface runoff, total water yield and the groundwater flow. This study assesses the impacts of the land cover and land use changes on the stream flows and hydrological water balance components (surface runoff, water yield, percolation and actual evapotranspiration). The land use and land cover (LULC) maps for three window period snapshots, 1990, 2006 and 2017 were created from Landsat TM and OLI_TIRS with the help of QGIS version 2.6. Supervised classification was used to generate LULC maps using the Maximum Likelihood Algorithm and Kappa statistics for assessment of accuracy. SWAT was set up and run to simulate stream flows and hydrological water balance components. The assessment of the impacts of land use and land cover changes on stream flows and hydrological water balance component was performed by comparing hydrological parameters simulated by SWAT using land use scenarios of 2006 and 2017 against the baseline land use scenario of 1990. Accuracy of LULC classification was good with Kappa statistics ranging between 0.9 and 0.99. There was a drastic increase in areal coverage of cultivated land, for periods 1990-2006 (5.84%) and 2006-2017 (12.05%) compared to other LULC. During 2006 and 2017 surface runoff increased by 4% and 9% respectively;however, water yield increased by only 0.5% compared to 1990 baseline period. This was attributed to increased proportion of cultivated land in the sub-catchment which has a high curve number (59.60) that indicates a higher runoff response and low infiltration rate. 展开更多
关键词 Geographic Information System (GIS) Mbarali River Sub-Catchment Land Use and Cover change Soil and WATER Assessment Tool (SWAT) WATER Balance Stream Flow
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Assessing gray matter volume in patients with idiopathic rapid eye movement sleep behavior disorder 被引量:3
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作者 Xian-Hua Han Xiu-Ming Li +6 位作者 Wei-Jun Tang Huan Yu Ping Wu Jing-Jie Ge Jian Wang Chuan-Tao Zuo Kuang-Yu Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第5期868-875,共8页
Idiopathic rapid eye movement sleep behavior disorder(iRBD) is often a precursor to neurodegenerative disease. However, voxel-based morphological studies evaluating structural abnormalities in the brains of iRBD patie... Idiopathic rapid eye movement sleep behavior disorder(iRBD) is often a precursor to neurodegenerative disease. However, voxel-based morphological studies evaluating structural abnormalities in the brains of iRBD patients are relatively rare. This study aimed to explore cerebral structural alterations using magnetic resonance imaging and to determine their association with clinical parameters in iRBD patients. Brain structural T1-weighted MRI scans were acquired from 19 polysomnogram-confirmed iRBD patients(male:female 16:3; mean age 66.6 ± 7.0 years) and 20 age-matched healthy controls(male:female 5:15; mean age 63.7 ± 5.9 years). Gray matter volume(GMV) data were analyzed based on Statistical Parametric Mapping 8, using a voxel-based morphometry method and two-sample t-test and multiple regression analysis. Compared with controls, iRBD patients had increased GMV in the middle temporal gyrus and cerebellar posterior lobe, but decreased GMV in the Rolandic operculum, postcentral gyrus, insular lobe, cingulate gyrus, precuneus, rectus gyrus, and superior frontal gyrus. iRBD duration was positively correlated with GMV in the precuneus, cuneus, superior parietal gyrus, postcentral gyrus, posterior cingulate gyrus, hippocampus, lingual gyrus, middle occipital gyrus, middle temporal gyrus, and cerebellum posterior lobe. Furthermore, phasic chin electromyographic activity was positively correlated with GMV in the hippocampus, precuneus, fusiform gyrus, precentral gyrus, superior frontal gyrus, cuneus, inferior parietal lobule, angular gyrus, superior parietal gyrus, paracentral lobule, and cerebellar posterior lobe. There were no significant negative correlations of brain GMV with disease duration or electromyographic activity in iRBD patients. These findings expand the spectrum of known gray matter modifications in iRBD patients and provide evidence of a correlation between brain dysfunction and clinical manifestations in such patients. The protocol was approved by the Ethics Committee of Huashan Hospital(approval No. KY2013-336) on January 6, 2014. This trial was registered in the ISRCTN registry(ISRCTN18238599). 展开更多
关键词 nerve REGENERATION IDIOPATHIC rapid eye movement sleep behavior disorder SYNUCLEINOPATHIES magnetic resonance imaging gray matter volume statistic parametric mapping voxel-based MORPHOMETRY structure Parkinsons disease NEURODEGENERATIVE diseases neural REGENERATION
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“Eternal Motion” as a “Form of Movement of a Special Nature” and the Main Condition for the Creation of the Universe
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作者 Avas Khugaev Eugeniya Bibaeva 《Journal of Applied Mathematics and Physics》 2024年第6期2041-2068,共28页
The article hypothesizes that DE and DM (UCM) are a “Form of Motion of a Special Nature”, where “Form of Motion” means “Eternal Motion” as the power of dynamics of different levels and varying degrees of self-su... The article hypothesizes that DE and DM (UCM) are a “Form of Motion of a Special Nature”, where “Form of Motion” means “Eternal Motion” as the power of dynamics of different levels and varying degrees of self-sufficiency, and by “Special Nature”, gravitational and two other properties of matter, “tied” to the “Eternal Movement” and completely dependent on it. Carriers of key properties of a “Special Nature” have been established: “0”-DE particles and “3”-DM particles (UDM). The unity of their inherent “motionally-gravitational” properties and the peculiarity of the relationship between “motion” and “gravity” are revealed: the higher the intensity of “Eternal Motion”, the stronger the gravitational properties of matter are manifested (and vice versa). The relationship of “time” with the “vibration frequency” and the “mass” of photons with the “degree of bonding and deformation properties of the field” is shown. The maximum level of gravity has been determined, which allows Nature to successfully create the Universe: such a landmark is the proximity to the property of the Primary Source—the “pure graviton” of the OSP space, the most powerful “motionally-gravitational” particle of the Universe. The reasons for the emergence of such an identity of the gravitational properties of particles with the indicators of a “pure graviton” are established: for “0”-DE particles, this is the acquisition of the function of “freedom of movement”;for “3”-DM particles (UDM), the creation of a special structure—a “double field” (“Main” and “Small”). The presence in the “double field” of specific “tools” for the creation of the worlds of the Universe—gravitational “waves” gives rise to impulses (shocks) of varying intensity and shape. A list of functions performed by “waves” in the “Main” and “Small” fields has been compiled. The specific conditions for the formation of “UDM Streams”, their transformation into a “Vortex” and, under the influence of a powerful Initial Impulse (push), sending them to the “place” of the creation of galaxies, are shown. It is suggested that there is a “Cycle of Matter in Nature” in the closed structure of our Universe due to the “work” of “waves” and the functioning of special “factories” in the form of exotic space objects—Black holes. 展开更多
关键词 DE DM (UCM) Graviton Eternal motion Double Field of the Universe Motionally-Gravitational Particles Degree of Self-Sufficiency Main Field Small Field Gravitational Waves Primary Impulse Flows UDM Vortex Time Massive Photons Clumps of DM movement of Galaxies Factories of Black Holes Circulation of Matter in Nature
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Constraint-induced movement therapy enhances angiogenesis and neurogenesis after cerebral ischemia/reperfusion 被引量:24
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作者 Zhi-Yong Zhai Juan Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第10期1743-1754,共12页
Constraint-induced movement therapy after cerebral ischemia stimulates axonal growth by decreasing expression levels of Nogo-A,RhoA,and Rho-associated kinase(ROCK)in the ischemic boundary zone.However,it remains uncle... Constraint-induced movement therapy after cerebral ischemia stimulates axonal growth by decreasing expression levels of Nogo-A,RhoA,and Rho-associated kinase(ROCK)in the ischemic boundary zone.However,it remains unclear if there are any associations between the Nogo-A/RhoA/ROCK pathway and angiogenesis in adult rat brains in pathological processes such as ischemic stroke.In addition,it has not yet been reported whether constraint-induced movement therapy can promote angiogenesis in stroke in adult rats by overcoming Nogo-A/RhoA/ROCK signaling.Here,a stroke model was established by middle cerebral artery occlusion and reperfusion.Seven days after stroke,the following treatments were initiated and continued for 3 weeks:forced limb use in constraint-induced movement therapy rats(constraint-induced movement therapy group),intraperitoneal infusion of fasudil(a ROCK inhibitor)in fasudil rats(fasudil group),or lateral ventricular injection of NEP1-40(a specific antagonist of the Nogo-66 receptor)in NEP1-40 rats(NEP1-40 group).Immunohistochemistry and western blot assay results showed that,at 2 weeks after middle cerebral artery occlusion,expression levels of RhoA and ROCK were lower in the ischemic boundary zone in rats treated with NEP1-40 compared with rats treated with ischemia/reperfusion or constraint-induced movement therapy alone.However,at 4 weeks after middle cerebral artery occlusion,expression levels of RhoA and ROCK in the ischemic boundary zone were markedly decreased in the NEP1-40 and constraint-induced movement therapy groups,but there was no difference between these two groups.Compared with the ischemia/reperfusion group,modified neurological severity scores and foot fault scores were lower and time taken to locate the platform was shorter in the constraint-induced movement therapy and fasudil groups at 4 weeks after middle cerebral artery occlusion,especially in the constraint-induced movement therapy group.Immunofluorescent staining demonstrated that fasudil promoted an immune response of nerve-regeneration-related markers(BrdU in combination with CD31(platelet endothelial cell adhesion molecule),Nestin,doublecortin,NeuN,and glial fibrillary acidic protein)in the subventricular zone and ischemic boundary zone ipsilateral to the infarct.After 3 weeks of constraint-induced movement therapy,the number of regenerated nerve cells was noticeably increased,and was accompanied by an increased immune response of tight junctions(claudin-5),a pericyte marker(a-smooth muscle actin),and vascular endothelial growth factor receptor 2.Taken together,the results demonstrate that,compared with fasudil,constraint-induced movement therapy led to stronger angiogenesis and nerve regeneration ability and better nerve functional recovery at 4 weeks after cerebral ischemia/reperfusion.In addition,constraint-induced movement therapy has the same degree of inhibition of RhoA and ROCK as NEP1-40.Therefore,constraint-induced movement therapy promotes angiogenesis and neurogenesis after cerebral ischemia/reperfusion injury,at least in part by overcoming the Nogo-A/RhoA/ROCK signaling pathway.All protocols were approved by the Institutional Animal Care and Use Committee of China Medical University,China on December 9,2015(approval No.2015 PS326 K). 展开更多
关键词 nerve REGENERATION constraint-induced movement therapy ANGIOGENESIS ISCHEMIA/REPERFUSION subventricular zone NOGO-A FASUDIL NEUROVASCULAR unit tight junction protein vascular endothelial growth factor receptor 2 neural REGENERATION
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Early constraint-induced movement therapy affects behavior and neuronal plasticity in ischemia-injured rat brains 被引量:13
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作者 Xi-Hua Liu Hong-Yan Bi +2 位作者 Jie Cao Shuo Ren Shou-Wei Yue 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第5期775-782,共8页
Constraint-induced movement therapy is an effective rehabilitative training technique used to improve the restoration of impaired upper extremity movement after stroke. However, whether constraint-induced movement the... Constraint-induced movement therapy is an effective rehabilitative training technique used to improve the restoration of impaired upper extremity movement after stroke. However, whether constraint-induced movement therapy is more effective than conventional rehabilitation in acute or sub-acute stroke remains controversial. The aim of the present study was to identify the optimal time to start constraint-induced movement therapy after ischemic stroke and to explore the mechanisms by which constraint-induced movement therapy leads to post-stroke recovery. Sixty-four adult male Sprague-Dawley rats were randomly divided into four groups: sham-surgery group, cerebral ischemia/reperfusion group, early constraint-induced movement therapy group, and late constraint-induced movement therapy group. Rat models of left middle cerebral artery occlusion were established according to the Zea Longa line embolism method. Constraint-induced movement therapy was conducted starting on day 1 or day 14 in the early constraint-induced movement therapy and late constraint-induced movement therapy groups, respectively. To explore the effect of each intervention time on neuromotor function, behavioral function was assessed using a balance beam walking test before surgery and at 8 and 21 days after surgery. The expression levels of brain-derived neurotrophic factor, nerve growth factor and Nogo receptor were evaluated using real time-polymerase chain reaction and western blot assay to assess the effect of each intervention time. The results showed that the behavioral score was significantly lower in the early constraint-induced movement therapy group than in the cerebral ischemia/reperfusion and late constraint-induced movement therapy groups at 8 days. At 21 days, the scores had significantly decreased in the early constraint-induced movement therapy and late constraint-induced movement therapy groups. At 8 days, only mild pyknosis appeared in neurons of the ischemic penumbra in the early constraint-induced movement therapy group, which was distinctly better than in the cerebral ischemia/reperfusion group. At 21 days, only a few vacuolated cells were observed and no obvious inflammatory cells were visible in late constraint-induced movement therapy group, which was much better than at 8 days. The mRNA and protein expression levels of brain-derived neurotrophic factor and nerve growth factor were significantly higher, but expression levels of Nogo receptor were significantly lower in the early constraint-induced movement therapy group compared with the cerebral ischemia/reperfusion and late constraint-induced movement therapy groups at 8 days. The changes in expression levels at 21 days were larger but similar in both the early constraint-induced movement therapy and late constraint-induced movement therapy groups. Besides, the protein nerve growth factor level was higher in the late constraint-induced movement therapy group than in the early constraint-induced movement therapy group at 21 days. These results suggest that both early(1 day) and late(14 days) constraint-induced movement therapy induces molecular plasticity and facilitates functional recovery after ischemic stroke, as illustrated by the histology. The mechanism may be associated with downregulation of Nogo receptor expression and upregulation of brain-derived neurotrophic factor and nerve growth factor expression. 展开更多
关键词 NERVE REGENERATION ischemic stroke rehabilitation constraint-induced movement therapy NERVE growth factors functional recovery neuronal plasticity real time-polymerase chain reaction western BLOT assay rats neural REGENERATION
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Combined Sciatic-Lumbar Plexus Block with General Anesthesia: Efficacy in Preventing Tourniquet-Induced Hemodynamic Changes
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作者 Raham Hasan Mostafa 《Open Journal of Anesthesiology》 2018年第3期100-111,共12页
Background: Pneumatic arterial tourniquet is a utilized strategy in limb surgeries to provide bloodless field to facilitate surgical procedure. Be that as it may, arterial tourniquet has numerous injurious impacts inc... Background: Pneumatic arterial tourniquet is a utilized strategy in limb surgeries to provide bloodless field to facilitate surgical procedure. Be that as it may, arterial tourniquet has numerous injurious impacts including hemodynamic changes and tourniquet-induced pain which sometimes can be severe and intolerable. Objectives: Our primary aim was to assess the impact of performing “Lumbar Plexus Block and sciatic nerve block” with General Anesthesia (GA) on the degree of arterial tourniquet-induced hemodynamic effects. On the other hand, our secondary aims were: amount of postoperative analgesic prerequisites, patient satisfactory score and documented side effects. Settings and Design: Ain Shams University, Orthopedic operating theatre;a prospective, randomized, double-blind study. Methods and Material: The physical status of 50 patients (both sexes) including I and II patients from American Society of Anesthesiologists, whose ages are from 20 - 40 years, is not so ideal when they are undergoing elective knee Arthroscopy. The duration lasts no more than ninety minutes under GA with application of tourniquet. Patients were allotted haphazardly to one of two groups. In Group C (Control group): Only GA. In Group B: LPB and sciatic nerve block were performed just before GA administration. Intraoperative hemodynamics was recorded at specific timings. Results: Incidence of tourniquet induced hypertension (TIH) was markedly less with Group B at: forty five, sixty, seventy five mins after tourniquet inflation and just before tourniquet deflation. Also, the total ketorolac consumption during first 24 hours of postoperative period was significantly less with Group B (p Conclusions: Combined Sciatic-Lumbar plexus blocks when combined with general anesthesia were very effective in attenuating TIH. 展开更多
关键词 General Anesthesia Lumbar PLEXUS Blocks ORTHOPEDIC Surgery Postoperative Analgesia SCIATIC Nerve Block TOURNIQUET INDUCED HEMODYNAMIC changes
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Diffusion kurtosis imaging of microstructural changes in brain tissue affected by acute ischemic stroke in different locations 被引量:27
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作者 Liu-Hong Zhu Zhong-Ping Zhang +2 位作者 Fu-Nan Wang Qi-Hua Cheng Gang Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第2期272-279,共8页
The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient(ADC), cannot reveal microstructural changes in different locati... The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient(ADC), cannot reveal microstructural changes in different locations or the degree of infarction. This prospective observational study was reviewed and approved by the Institutional Review Board of Xiamen Second Hospital, China(approval No. 2014002).Diffusion kurtosis imaging(DKI) was used to detect 199 lesions in 156 patients with acute ischemic stroke(61 males and 95 females), mean age 63.15 ± 12.34 years. A total of 199 lesions were located in the periventricular white matter(n = 52), corpus callosum(n = 14), cerebellum(n = 29), basal ganglia and thalamus(n = 21), brainstem(n = 21) and gray-white matter junctions(n = 62). Percentage changes of apparent diffusion coefficient(ΔADC) and DKI-derived indices(fractional anisotropy [ΔFA], mean diffusivity [ΔMD], axial diffusivity [ΔD_a], radial diffusivity ΔDr, mean kurtosis [ΔMK], axial kurtosis [ΔK_a], and radial kurtosis [ΔK_r]) of each lesion were computed relative to the normal contralateral region. The results showed that(1) there was no significant difference in ΔADC, ΔMD, ΔD_a or ΔD_r among almost all locations.(2) There was significant difference in ΔMK among almost all locations(except basal ganglia and thalamus vs. brain stem; basal ganglia and thalamus vs. gray-white matter junctions; and brainstem vs. gray-white matter junctions.(3) The degree of change in diffusional kurtosis in descending order was as follows: corpus callosum > periventricular white matter > brainstem > gray-white matter junctions > basal ganglia and thalamus > cerebellum. In conclusion, DKI could reveal the differences in microstructure changes among various locations affected by acute ischemic stroke, and performed better than diffusivity among all groups. 展开更多
关键词 nerve REGENERATION APPARENT DIFFUSION coefficient DIFFUSION weighted IMAGING DIFFUSION KURTOSIS IMAGING acute ischemic stroke mean KURTOSIS microstructure changes white matter 1.5 TESLA magnetic resonance system neural REGENERATION
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Intelligent Biometric Information Management
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作者 Harry Wechsler 《Intelligent Information Management》 2010年第9期499-511,共13页
We advance here a novel methodology for robust intelligent biometric information management with inferences and predictions made using randomness and complexity concepts. Intelligence refers to learning, adap- tation,... We advance here a novel methodology for robust intelligent biometric information management with inferences and predictions made using randomness and complexity concepts. Intelligence refers to learning, adap- tation, and functionality, and robustness refers to the ability to handle incomplete and/or corrupt adversarial information, on one side, and image and or device variability, on the other side. The proposed methodology is model-free and non-parametric. It draws support from discriminative methods using likelihood ratios to link at the conceptual level biometrics and forensics. It further links, at the modeling and implementation level, the Bayesian framework, statistical learning theory (SLT) using transduction and semi-supervised lea- rning, and Information Theory (IY) using mutual information. The key concepts supporting the proposed methodology are a) local estimation to facilitate learning and prediction using both labeled and unlabeled data;b) similarity metrics using regularity of patterns, randomness deficiency, and Kolmogorov complexity (similar to MDL) using strangeness/typicality and ranking p-values;and c) the Cover – Hart theorem on the asymptotical performance of k-nearest neighbors approaching the optimal Bayes error. Several topics on biometric inference and prediction related to 1) multi-level and multi-layer data fusion including quality and multi-modal biometrics;2) score normalization and revision theory;3) face selection and tracking;and 4) identity management, are described here using an integrated approach that includes transduction and boosting for ranking and sequential fusion/aggregation, respectively, on one side, and active learning and change/ outlier/intrusion detection realized using information gain and martingale, respectively, on the other side. The methodology proposed can be mapped to additional types of information beyond biometrics. 展开更多
关键词 Authentication Biometrics Boosting change DETECTION Complexity Cross-Matching Data Fusion Ensemble Methods Forensics Identity MANAGEMENT Imposters Inference INTELLIGENT Information MANAGEMENT Margin gain MDL Multi-Sensory Integration Outlier DETECTION P-VALUES Quality Randomness Ranking Score Normalization Semi-Supervised Learning Spectral Clustering STRANGENESS Surveillance Tracking TYPICALITY Transduction
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Augmenting the Heat Sink for Better Heat Dissipation
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作者 Mohammed H. S. Al Ashry 《Circuits and Systems》 2015年第2期21-29,共9页
Heat sinks were invented to absorb heat from an electronic circuit conduct, and then to dissipate or radiate this heat to the surrounding supposedly, ventilated space, at a rate equal to or faster than that of its bui... Heat sinks were invented to absorb heat from an electronic circuit conduct, and then to dissipate or radiate this heat to the surrounding supposedly, ventilated space, at a rate equal to or faster than that of its buildup. Ventilation was not initially recognized as an essential factor to thermal dispersion. However, as electronic circuit-boards continued to heat up, circuit failure became a problem, forcing the inclusion of miniaturized high speed fans. Later, heat sinks with fins and quiet fans were incorporated in most manufactured circuits. Now heat sinks come in the form of a fan with fans made to function as fins to disperse heat. Heat sinks absorb and radiate excess heat from circuit-boards in order to prolong the circuit’s life span. The higher the thermal conductivity of the material used the more efficient and effective the heat sink is. This paper is an attempt to theoretically design a heat sink with a temperature gradient lower than that of the circuit board’s excess heat. 展开更多
关键词 CONVECTIVE HEAT Transfer: HEAT Absorbed by the Natural AIR Flow Surrounding Hot Objects FORCED CONVECTIVE HEAT Transfer: Absorption of HEAT Using FORCED AIR Flow Conductivity: Is the Ability of a System to Exchange or TRANSFER Temperature within a Body or MATERIAL through the movement of Electrons MATERIAL That Does Not Conduct HEAT Is Considered a Nonconductor
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Model of Universe as Described by Dynamic Universe Model
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作者 Satyavarapu Naga Parameswara Gupta 《Open Journal of Modelling and Simulation》 2019年第1期41-78,共38页
In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the m... In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the matter here, we will see in part 1: about the Galaxy life cycle, where the birth and death of Galaxies discussed. Probably Universe gives guidance for the movement of Galaxies. We call this Part 1: Thinking and Reproducing Universe or Mindless Universe? (Galaxy life cycle). We see every day Sun, Stars, Galaxies etc., dissipating enormous energy in the form of radiation by the way of fusion of Hydrogen to helium. So after sometime all the Hydrogen is spent and Universe will die, is it not? … Dynamic Universe Model says that the energy in the form of electromagnetic radiation passing grazingly near any gravitating mass changes in frequency and finally will convert into neutrinos (mass). Hence Dynamic Universe Model proposes another process where energy will be converted back into matter and the cycle energy to mass to energy continues, sustaining the Universe to maintain this present status for ever in this form something like a Steady state model without any expansion. This we will see in Part 2: Energy - Mass - Energy Cycle. After converting energy into mass “how various elements are formed and where they are formed?” will be next logical question. Dynamic Universe Model says that these various particles change into higher massive particles or may get bombarded into stars or planets and various elements are formed. Here we bifurcate the formation of elements into 6 processes. They are for Elementary particles and elements generated in frequency changing process, By Cosmic rays, By Small stars, By Large Stars, By Super Novae and Manmade elements By Neutron Stars. This we will discuss in Part 3: Nucleosynthesis. 展开更多
关键词 DYNAMIC UNIVERSE MODEL Hubble Space Telescope (HST) SITA Simulations (SITA-Simulation of Inter Intra Tautness Attraction Forces Used by DYNAMIC UNIVERSE Model) Singularity-Free COSMOLOGY Blue Shifted GALAXIES Red Shifted GALAXIES Grazing Radiation Frequency changes Formation of Elements Nucleosynthesis DYNAMIC UNIVERSE MODEL Energy to Mass Conversion Methods: N-Body Simulations-Gravitation-Cosmology
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Relevance of a standard food model in combination with electronic jaw movement recording on human mastication pattern analysis
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作者 Gregor Slavicek Mikhael Soykher +2 位作者 Marina Soykher Haymo Gruber Peter Siegl 《Advances in Bioscience and Biotechnology》 2010年第2期68-78,共11页
The aim of this paper is to describe the possibilities of analyzing human mastication. The development of a standardized food model is presented. Based on the findings of a systematic literature search an elastic food... The aim of this paper is to describe the possibilities of analyzing human mastication. The development of a standardized food model is presented. Based on the findings of a systematic literature search an elastic food model was created with the aim of standardizing size and elastic properties. Three different eatable jellied products were chosen, created by a changing of the amount of gelatin (260 Blooms) related to the total mass of the standard jellied food. The different hardness were classified in soft, medium and hard, flavored identically, but stained with different colors: soft-green, medium-yellow, hard-red. A cylindrical form was chosen with a height of 1 cm and a diameter of 2 cm. A standard protocol for analyzing chewing patterns in men was created. The condylographic data off several patients are described in details to demonstrate the possible clinical implementation. The newly developed standard food model (SFM) showed the capability to serve in experimental settings to analyze human mastication, although only a few patients have been examined. In addition, strength and size of the newly developed SFM load the masticatory system in an extent;it should be possible to disclose subclinical symptoms of patients within a short time of examination. The diagnostic procedure of temporo-mandibular disorder (TMD) should be endorsed by this new method. The condylographic data created by a standardized protocol should have the ability to enhance the clinical functional analysis of patients previous to restorative dental procedures. 展开更多
关键词 HUMAN MASTICATION STANDARD Food Model MANDIBULAR movement EMG Condylography Biomechanics Temporo-Mandibular Joint SWALLOWING CHEWING CHEWING Muscle Activity Craniomandibular System Nutrition Tooth Loss
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The Use of Indigenous Knowledge in Predicting Changes in Seasonal Rainfall by Smallholder Farmers of Ruteete Subcounty, Kabarole District 被引量:1
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作者 Kandida Nyakaisiki Isaac Mugume +1 位作者 Triphonia Ngailo Rhoda Nakabugo 《Journal of Geoscience and Environment Protection》 2019年第1期13-22,共10页
Climate change has become a serious global challenge. Developing countries are the worst affected due to poor response mechanism to associated disasters. This study examined the application of the indigenous knowledge... Climate change has become a serious global challenge. Developing countries are the worst affected due to poor response mechanism to associated disasters. This study examined the application of the indigenous knowledge (IK) methods to predict the changes in seasonal rainfall. The study used data collected through individual interviews using a structured questionnaire. The study found vegetation changes (i.e. shading off leaves, excessive branching);changes in animal behavior (i.e. eating soil, restlessness), and other atmospheric indicators (i.e. changes in wind, color of stars and moon, earthquake, migrating of birds, swarming of bees, cold windy mornings and warm nights) being used to observe and monitor the changes in rainfall over the season. The study recommends a more detailed study to validate the IK and integrate it with the scientific knowledge so as to reduce local farmers’ vulnerability, increase resilience and strengthen their adaptive capacity to cope with climate change effects. 展开更多
关键词 Indigenous Knowledge PREDICTORS of SEASONAL RAINFALL CLIMATE change Adaptation INDICATORS of changeS in CLIMATE
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Assessing and Predicting Changes in the Status of Gambari Forest Reserve, Nigeria Using Remote Sensing and GIS Techniques 被引量:1
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作者 Oludare H. Adedeji Opeyemi O. Tope-Ajayi Olukemi L. Abegunde 《Journal of Geographic Information System》 2015年第3期301-318,共18页
Rapid population growth and increasing economic activities have resulted in unsustainable exploitation and rapid decline in the spatial extent of forest reserves in Nigeria. Studying land use dynamics of these forest ... Rapid population growth and increasing economic activities have resulted in unsustainable exploitation and rapid decline in the spatial extent of forest reserves in Nigeria. Studying land use dynamics of these forest reserves is essential for analysing various ecological and developmental consequences over time. Land use/land cover mapping, change detection and prediction are essential for decision-making and implementing appropriate policy responses relating to land uses. This paper aims at assessing and predicting changes in land use/land cover at Gambari forest reserve, Nigeria using remote sensing and GIS techniques. The study determined the magnitude, rate and dynamics of change in the spatial extent of the forest reserve between 1984 and 2014 using multi-temporal datasets (Landsat TM 1984 and 2000 and OLI/TIRS 2014). The imageries were classified using ArcGIS 10.0 version with support of ground truth data and Land use Change Modeller (LCM) and Markovian processes were employed to analyse the pattern and trend of change. Prediction of 2044 scenario carried out using neural network, which is a built-in module in the Idrisi. The study revealed dramatic decline in the extent of the forest reserve as both the plantation of exotic tree species (Tectona grandis and Gmelina) and the indigenous stands have been logged in several places for timber and to make way for cultivation of crops. In addition, pressures from other land uses like settlements have also led to increased non-forest uses particularly bare grounds. The study concluded that increasing loss of the indigenous forest and plantation would continue thus having implications for biodiversity conservation in the study area. There is the need for participation of different stakeholders and sectors to solve conflicting demands on limited forest resources and ensure ecosystem integrity. 展开更多
关键词 change Detection GIS Gambari FOREST RESERVE FOREST Degradation Idrisi LCM Satellite REMOTE Sensing
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Mapping of moraine dammed glacial lakes and assessment of their areal changes in the central and eastern Himalayas using satellite data 被引量:3
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作者 Sazeda BEGAM Dhrubajyoti SEN 《Journal of Mountain Science》 SCIE CSCD 2019年第1期77-94,共18页
The relatively rapid recession of glaciers in the Himalayas and formation of moraine dammed glacial lakes(MDGLs) in the recent past have increased the risk of glacier lake outburst floods(GLOF) in the countries of Nep... The relatively rapid recession of glaciers in the Himalayas and formation of moraine dammed glacial lakes(MDGLs) in the recent past have increased the risk of glacier lake outburst floods(GLOF) in the countries of Nepal and Bhutan and in the mountainous territory of Sikkim in India. As a product of climate change and global warming, such a risk has not only raised the level of threats to the habitation and infrastructure of the region, but has also contributed to the worsening of the balance of the unique ecosystem that exists in this domain that sustains several of the highest mountain peaks of the world. This study attempts to present an up to date mapping of the MDGLs in the central and eastern Himalayan regions using remote sensing data, with an objective to analyse their surface area variations with time from 1990 through 2015, disaggregated over six episodes. The study also includes the evaluation for susceptibility of MDGLs to GLOF with the least criteria decision analysis(LCDA). Forty two major MDGLs, each having a lake surface area greater than 0.2 km2, that were identified in the Himalayan ranges of Nepal, Bhutan, and Sikkim, have been categorized according to their surface area expansion rates in space and time. The lakes have been identified as located within the elevation range of 3800 m and6800 m above mean sea level(a msl). With a total surface area of 37.9 km2, these MDGLs as a whole were observed to have expanded by an astonishing 43.6% in area over the 25 year period of this study. A factor is introduced to numerically sort the lakes in terms of their relative yearly expansion rates, based on their interpretation of their surface area extents from satellite imageries. Verification of predicted GLOF events in the past using this factor with the limited field data as reported in literature indicates that the present analysis may be considered a sufficiently reliable and rapid technique for assessing the potential bursting susceptibility of the MDGLs. The analysis also indicates that, as of now, there are eight MDGLs in the region which appear to be in highly vulnerable states and have high chances in causing potential GLOF events anytime in the recent future. 展开更多
关键词 GLACIER RETREAT LAKES MAPPING MORAINE dammed GLACIAL lake(MDGL) Surface area change of LAKES Landsat imagery data Least criteria decision analysis(LCDA)
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Modified constraint-induced movement therapy alters synaptic plasticity of rat contralateral hippocampus following middle cerebral artery occlusion 被引量:20
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作者 Bei-Yao Gao Dong-Sheng Xu +6 位作者 Pei-Le Liu Ce Li Liang Du Yan Hua Jian Hu Jia-Yun Hou Yu-Long Bai 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第6期1045-1057,共13页
Modified constraint-induced movement therapy is an effective treatment for neurological and motor impairments in patients with stroke by increasing the use of their affected limb and limiting the contralateral limb.Ho... Modified constraint-induced movement therapy is an effective treatment for neurological and motor impairments in patients with stroke by increasing the use of their affected limb and limiting the contralateral limb.However,the molecular mechanism underlying its efficacy remains unclear.In this study,a middle cerebral artery occlusion(MCAO)rat model was produced by the suture method.Rats received modified constraint-induced movement therapy 1 hour a day for 14 consecutive days,starting from the 7^th day after middle cerebral artery occlusion.Day 1 of treatment lasted for 10 minutes at 2r/min,day 2 for 20 minutes at 2 r/min,and from day 3 onward for 20 minutes at 4 r/min.CatWalk gait analysis,adhesive removal test,and Y-maze test were used to investigate motor function,sensory function as well as cognitive function in rodent animals from the 1st day before MCAO to the 21^st day after MCAO.On the 21^st day after MCAO,the neurotransmitter receptor-related genes from both contralateral and ipsilateral hippocampi were tested by micro-array and then verified by western blot assay.The glutamate related receptor was shown by transmission electron microscopy and the glutamate content was determined by high-performance liquid chromatography.The results of behavior tests showed that modified constraint-induced movement therapy promoted motor and sensory functional recovery in the middle cerebral artery-occluded rats,but had no effect on cognitive function.The modified constraint-induced movement therapy upregulated the expression of glutamate ionotropic receptor AMPA type subunit 3(Gria3)in the hippocampus and downregulated the expression of the beta3-adrenergic receptor gene Adrb3 and arginine vasopressin receptor 1 A,Avprla in the middle cerebral artery-occluded rats.In the ipsilateral hippocampus,only Adra2 a was downregulated,and there was no significant change in Gria3.Transmission electron microscopy revealed a denser distribution the more distribution of postsynaptic glutamate receptor 2/3,which is an a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor,within 240 nm of the postsynaptic density in the contralateral cornu ammonis 3 region.The size and distribution of the synaptic vesicles within 100 nm of the presynaptic active zone were unchanged.Western blot analysis showed that modified constraint-induced movement therapy also increased the expression of glutamate receptor 2/3 and brain-derived neurotrophic factor in the hippocampus of rats with middle cerebral artery occlusion,but had no effect on Synapsin I levels.Besides,we also found modified constraint-induced movement therapy effectively reduced glutamate content in the contralateral hippocampus.This study demonstrated that modified constraint-induced movement therapy is an effective rehabilitation therapy in middle cerebral artery-occluded rats,and suggests that these positive effects occur via the upregulation of the postsynaptic membrane a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor expression.This study was approved by the Institutional Animal Care and Use Committee of Fudan University,China(approval No.201802173 S)on March 3,2018. 展开更多
关键词 BRAIN-DERIVED NEUROTROPHIC factor glutamate HIPPOCAMPUS m CIMT middle cerebral artery occlusion MODIFIED constraint-induced movement therapy α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor
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西昆仑-塔西南坳陷晚古生代以来的沉积构造演化 被引量:42
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作者 方爱民 马建英 +2 位作者 王世刚 赵越 胡健民 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3396-3406,共11页
自柯克亚深层油气勘探取得突破以来,塔西南坳陷一直受到各类地质学家的广泛关注,有关该盆地的形成和演化历史及其油气资源评价近年来更是成为人们的研究热点。本文在总结前人资料的基础上,探讨塔西南和西昆仑地区自晚古生代以来所经历... 自柯克亚深层油气勘探取得突破以来,塔西南坳陷一直受到各类地质学家的广泛关注,有关该盆地的形成和演化历史及其油气资源评价近年来更是成为人们的研究热点。本文在总结前人资料的基础上,探讨塔西南和西昆仑地区自晚古生代以来所经历的构造及沉积格架的演变过程,对塔西南坳陷性质及其演化阶段划分所存在的争议进行了归纳,分析了塔西南-西昆仑这一盆山体系形成和演化中的构造变形和沉积记录。总体来说,根据现有沉积和构造变形资料,中生代之前西昆仑和塔西南坳陷分别处于同一构造背景下的不同沉积单元;二者之间盆山体系的形成主要自晚侏罗世-早白垩世,中-上新世是造盆造山作用机制发生重大转折的时期,或者说早更新世末的构造运动基本上奠定了西昆仑-塔里木盆地南缘现今的盆-山构造格架。 展开更多
关键词 西 西 LATE Paleozoic west KUNLUN orogen Tarim BASIN BASIN system KUNLUN orogenic belt tectonic movements structural geology sedimentary strata Early Pleistocene Early Cretaceous LATE Jurassic
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Dynamic changes of behaviors, dentate gyrus neurogenesis and hippocampal miR-124 expression in rats with depression induced by chronic unpredictable mild stress 被引量:13
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作者 Yun-Ling Huang Ning-Xi Zeng +5 位作者 Jie Chen Jie Niu Wu-Long Luo Ping Liu Can Yan Li-Li Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第6期1150-1159,共10页
The depression-like behavior phenotype,neurogenesis in the dentate gyrus and miR-124 expression in the hippocampus are the focus of current research on the pathogenesis of depression and antidepressant therapy.The pre... The depression-like behavior phenotype,neurogenesis in the dentate gyrus and miR-124 expression in the hippocampus are the focus of current research on the pathogenesis of depression and antidepressant therapy.The present study aimed to clarify the dynamic changes of depression-like behavior,dentate gyrus neurogenesis and hippocampal miR-124 expression during depression induced by chronic stress to reveal pathological features at different stages of depression and to further provide insight into depression treatment.Chronic unpredictable mild stress depression models were established by exposing Sprague-Dawley rats to various mild stressors,including white noise,thermal swimming,stroboscopic illumination,soiled cages,pairing with three other stressed animals,cold swimming,tail pinch,restraint and water and food deprivation.Chronic unpredictable mild stress model rats underwent dynamic observation from 1 to 8 weeks and were compared with a control group(normal feeding without any stressors).To observe changes in the depression-like behavior phenotype during chronic unpredictable mild stress-induced depression,a sucrose preference test was used to evaluate the degree of anhedonia.An open-field test was used to evaluate locomotor activity and anxiety status.Compared with the control group,chronic unpredictable mild stress rats lost weight but did not have a depression-like behavioral phenotype at 1-4 weeks.Chronic unpredictable mild stress rats presented decreased sucrose preference and locomotor activity at 5-8 weeks.In addition,chronic unpredictable mild stress rats did not have significant anxiety-like behavior during 1-8 weeks of modeling.To observe neurogenesis dysfunctions and changes in neuronal number in the dentate gyrus during chronic unpredictable mild stress-induced depression,markers(DCX and DCX/BrdU)of neural proliferation and differentiation and the neuronal marker NeuN were assessed by immunofluorescence.Compared with the control group,neurogenesis and the neuronal number in the dentate gyrus did not change from 2 to 6 weeks;however,neural proliferation and differentiation in the dentate gyrus decreased,and the number of neurons decreased until the eighth week in the chronic unpredictable mild stress group.Real-time quantitative reverse transcription polymerase chain reaction assays and fluorescence in situ hybridization were used to measure the expression of hippocampal miR-124 during chronic unpredictable mild stress-induced depression.The results showed that the expression of hippocampal miR-124 was unchanged during the first 4 weeks but increased from 5 to 6 weeks and decreased from 7 to 8 weeks compared with the control group.These findings indicate that during chronic unpredictable mild stress-induced depression,the behavioral phenotype,miR-124 expression in the hippocampus,neurogenesis in the dentate gyrus and neuronal numbers showed dynamic changes,which suggested that various pathological changes occur at different stages of depression.All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Guangzhou University of Chinese Medicine of China in March 2015. 展开更多
关键词 chronic unpredictable MILD stress model continuous observation DEPRESSION depression-like behavior dynamic changes hippocampus miR-124 NEUROGENESIS DYSFUNCTION NEURONAL loss
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POPULATION MOVEMENT AND THE CHANGE OF REGIONAL ECONOMY PATTERN 被引量:1
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作者 陆玉麒 《Chinese Geographical Science》 SCIE CSCD 1992年第3期32-40,共9页
Population movement is an important phenomenon in China in recent years. Its mechanism is: (1) thrust of more people and less land in the eastern region of China; (2) attraction of dual economy in the western region o... Population movement is an important phenomenon in China in recent years. Its mechanism is: (1) thrust of more people and less land in the eastern region of China; (2) attraction of dual economy in the western region of China; (3) national policy on preferential wages and grains for the western region. Population movement has an important effect on the change of regional division pattern in China: by the medium of the moving people, there forms another regional division pattern, i.e. rural industry system based on rural town industry; (2) there forms another profit mechanism compensated from the western region to the eastern region. It not only wins more profit in the eastern region, but also changes dual economy in the western region. Therefore, We should make choice of a comprehensible and encouraging attitude on population movement; a special government organization for general survey of the moving people should be set up at once. 展开更多
关键词 POPULATION movement SHORTAGE of industrial structure regional DIVISION PATTERN RURAL industry
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The Pursuit of Fallacy in Density Functional Theory: The Quest for Exchange and Correlation, the Rigorous Treatment of Exchange in the Kohn-Sham Formalism and the Continuing Search for Correlation
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作者 A. Gonis 《World Journal of Condensed Matter Physics》 2014年第3期200-225,共26页
As pointed out in the paper preceding this one, in the case of functionals whose independent variable must obey conditions of integral normalization, conventional functional differentiation, defined in terms of an arb... As pointed out in the paper preceding this one, in the case of functionals whose independent variable must obey conditions of integral normalization, conventional functional differentiation, defined in terms of an arbitrary test function, is generally inapplicable and functional derivatives with respect to the density must be evaluated through the alternative and widely used limiting procedure based on the Dirac delta function. This leads to the determination of the rate of change of the dependent variable with respect to its independent variable at each isolated pair, , that may not be part of a functional (a set of ordered pairs). This extends the concept of functional derivative to expectation values of operators with respect to wave functions leading to a density even if the wave functions (and expectation values) do not form functionals. This new formulation of functional differentiation forms the basis for the study of the mathematical integrity of a number of concepts in density functional theory (DFT) such as the existence of a universal functional of the density, of orbital-free density functional theory, the derivative discontinuity of the exchange and correlation functional and the extension of DFT to open systems characterized by densities with fractional normalization. It is shown that no universal functional exists but, rather, a universal process based only on the density and independent of the possible existence of a potential, leads to unique functionals of the density determined through the minimization procedure of the constrained search. The mathematical integrity of two methodologies proposed for the treatment of the Coulomb interaction, the self-interaction free method and the optimized effective potential method is examined and the methodologies are compared in terms of numerical calculations. As emerges from this analysis, the optimized effective potential method is found to be numerically approximate but formally invalid, contrary to the rigorously exact results of the self-interaction-free method. 展开更多
关键词 DENSITY FUNCTIONAL THEORY Variational Properties of DENSITY FUNCTIONAL THEORY Self-Interaction Error Optimized Effective Potential FUNCTIONAL DERIVATIVE Parametric DERIVATIVE FUNCTIONAL Rate of change DERIVATIVE Discontinuity Orbital-Free DENSITY FUNCTIONAL THEORY EXchange and CORRELATION FUNCTIONAL
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慢性氟中毒大鼠肾脏自由基含量与形态学变化 被引量:21
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作者 高勤 王守立 +2 位作者 于燕妮 刘家骝 肖开棋 《贵州医药》 CAS 2005年第3期213-215,共3页
目的研究慢性氟中毒大鼠肾脏自由基含量与形态学变化的关系。方法Wistar大鼠随机分为三组。正常对照组,未作任何处理;染氟组,自由饮用含氟化钠132.6mg/L的含氟水;抗氧化中药—染氟组,自由饮用含氟化钠132.6mg/L的含氟水,同时每日经腹腔... 目的研究慢性氟中毒大鼠肾脏自由基含量与形态学变化的关系。方法Wistar大鼠随机分为三组。正常对照组,未作任何处理;染氟组,自由饮用含氟化钠132.6mg/L的含氟水;抗氧化中药—染氟组,自由饮用含氟化钠132.6mg/L的含氟水,同时每日经腹腔内注射抗氧化中药丹参绞股蓝复方3.125毫克/公斤/天,实验6个月时检查动物。用电子自旋共振的方法检测肾组织内自由基的含量,并观察肾脏的形态学变化。结果与正常对照组动物相比,染氟组自由基明显升高,电镜下见肾小管上皮细胞有巨大线粒体及髓鞘样结构形成,内质网扩张,粗面内质网上核糖体脱落,细胞浆内游离核糖体增加,胞核内异染色质有向核膜下聚集的趋势;光镜下呈颗粒性变,偶见坏死。抗氧化中药一染氟组肾组织中自由基含量不增高,光镜及电镜下均未见明显病变。结论慢性氟中毒时肾脏病变与自由基含量增多有密切关系。 展开更多
关键词 wistar 线
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