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Glucocorticoids and nervous system plasticity

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Neural Regeneration Research 2016年第1期11卷 37-41页

作者： Kathryn m.madalena Jessica K.Lerch Center for Brain and Spinal Cord Repair The Ohio State University Department of Neuroscience Wexner Medical Center at The Ohio State University

Glucocorticoid and glucocorticoid receptor（GC/GR） interactions alter numerous aspects of neuronal function. These consequences（e.g., anti-inflammatory vs. pro-inflammatory） can vary depending on the duration of GC exposure or central nervous system（CNS） injury model. In this review we discuss how GC/GR interactions impact neuronal recovery after a central or peripheral nerve injury and discuss how GC exposure duration can produce divergent CNS neuronal growth responses. Finally we consider how new findings on gender specific immune cell responses after a nerve injury could intersect with GC/GR interactions to impact pain processing.

关键词： glucocorticoids plasticity stress neuropathic pain

Investigation of a New Formula for Gurney Velocity estimation

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火炸药学报 2018年第4期41卷 340-344页

作者： Tamer elshenawy Ahmed elbeih Qing ming Li Gamal m. Abdo Technical Research Centre Cairo Egypt military Technical College Kobry Elkobbah Cairo Egypt The University of manchester School of Mechanical Aerospace and Civil Engineering Manchester UK mechanical engineering Department Modern Acade

The formula for the analytical calculations of the shaped charge jetting parameters exhibit an explicit dependence upon the Gurney velocity of an explosive *** attempts have been done to approximate the characteristic constant 2e^(1/2) and to make its use more *** is shown herein that the characteristic Gurney velocity parameter depends on the ratio of the Chapman Jouguet-pressure to explosive impulse ratio by the formula:2e^(1/2)=0.2415(P_(CJ)/I_(SP)ρ_0)-970.76,where PCJis the Chapman Jouguet pressure(Pa),ISPis the specific impulse of the explosive used as a monopropellant(N·s/kg)andρois the explosive density(kg/m^3).The proposed empirical formula was found to be reasonable and quite accurate approximation that can be implemented over a wide range of explosives,where the maximum deviation between the measured and the calculated Gurney velocities was nearly 6%.Besides,the proposed approach has been used analytically to calculate the jet tip velocity of a small caliber shaped charge,which is measured *** difference between the measured and the calculated jet tip velocity was only 1.6%.

关键词：火药理论研究化学分析

Low-altitude geophysical magnetic prospecting based on multirotor UAV as a promising replacement for traditional ground survey

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Geo-Spatial Information Science 2018年第1期21卷 67-74页

作者： Alexander V.Parshin Vladimir A.morozov Anton V.Blinov Alexey N.Kosterev Alexander e.Budyak Ore Geology Lab Vinogradov Institute of Geochemistry SB RASIrkutskRussia SibGISTech LLC MarkovaRussia Geoinformatics Lab Irkutsk National Research Technical UniversityIrkutskRussia

The prospects for expanding the mineral resource base in many countries are linked with the exploration of stranded sites localized at unexplored areas with complex natural and landscape conditions that make any ground survey,including magnetic prospecting,difficult and *** current level of geology requires high-precision and large-scale data at the first stages of geological *** 2012,technologies of aeromagnetic surveying with unmanned aircraft vehicles(UAV)enter the market,but most of them are based on big fixed-wing UAV and do not allow to substantially increase the level of survey granularity compared with traditional aerial *** increase the scale of survey,it is necessary to reduce the altitude and speed of flight,for which the authors develop the methodical and technical solutions described in this *** obtain data at altitudes of 5 m above the terrain even in a rugged relief,we created heavy multirotor UAVs that are stable in flight and may be used in a wide range of environmental conditions(even a moderate snowfall),and develop a special software to generate flight missions on the basis of digital elevation models.A UAV has special design to reduce magnetic interference of the flight platform;the magnetic sensor is hung below the *** technology was conducted in a considerable amount of magnetic surveys in the mountainous regions of east Siberia between 2014 and *** results of the comparison between airborne and ground surveys are presented,which show that the sensitivity of the developed system in conjunction with low-altitude measurements can cover any geologically significant anomalies of the magnetic *** unmanned survey is cheaper and more productive;the multirotor-based technologies may largely replace traditional ground magnetic exploration in scales of 1:10,000−1:1000.

关键词： Unmanned aircraft vehicles(UAV) magnetic survey geophysical prospecting airborne geophysics unmanned aerial system(UAS)

effects of size-dependent elasticity on stability of nanotweezers

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Applied mathematics and mechanics(english edition) 2014年第12期35卷 1573-1590页

作者： A.FARROKHABADI A.KOOCHI A.KAZemI m.ABADYAN Department of Aerospace engineering Semnan UniversitySemnan 35131-19111 Iran mechanical engineering Group Shahrekord Branch Islamic Azad UniversityShahrekord 88137-33395 Iran Department of Physics University of BathBath BA2-7AY U.K.

It is well-recognized that the electromechanical response of a nanostructure is affected by its element size. In the present article, the size dependent stability behavior and nanotweezers fabricated from nanowires are investigated by modified couple stress elasticity （mCSe）. The governing equation of the nanotweezers is obtained by taking into account the presence of Coulomb and intermolecular attractions. To solve the equation, four techniques, i.e., the modified variational iteration method （mVIm）, the monotonic iteration method （mIm）, the mAPLe numerical solver, and a lumped model, are used. The variations of the arm displacement of the tweezers versus direct current （DC） voltage are obtained. The instability parameters, i.e., pull-in voltage and deflection of the system, are computed. The results show that size-dependency will affect the stability of the nanotweezers significantly if the diameter of the nanowire is of the order of the length scale. The impact of intermolecular attraction on the size-dependent stability of the system is discussed.

关键词： nanotweezer nanowire stability analysis modified couple stress elasticity(mCSe) intermolecular force

multi-solitons of Thermophoretic motion equation Depicting the Wrinkle Propagation in Substrate-Supported Graphene Sheets

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Communications in Theoretical Physics 2019年第4期71卷 362-366页

作者： Ahmad Javid Nauman Raza m.S.Osman Department of mathematics University of the Punjab Quaid-e-Azam Campus Department of mathematics Faculty of Science Cairo University Department of mathematics Duba University College University of Tabuk

The paper addresses the thermophoretic motion(Tm) equation, which is serviced to describe soliton-like thermophoresis of wrinkles in graphene sheet based on Korteweg-de Vries(KdV) equation. The generalized uni?ed method is capitalized to construct wrinkle-like multiple soliton solutions. Graphical analysis of one, two, and threesoliton solutions is carried out to depict certain properties like width, amplitude, shape, and open direction are adjustable through various parameters.

关键词： thermophoretic motion equation generalized unified method multiple soliton solution graphene sheets

Characteristics of a heavy water photoneutron source in boron neutron capture therapy

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Chinese Physics C 2013年第7期37卷 88-92页

作者： Danial Salehi Dariush Sardari m. Salehi Jozani Department of Radiological and Nuclear engineering Science and Research Branch Islamic Azad University Department of electrical engineering Islamic Azad University South Tehran Branch

Bremsstrahlung photon beams produced by medical linear accelerators are currently the most commonly used method of radiation therapy for cancerous tumors. Photons with energies greater than 8-10 meV potentially generate neutrons through photonuclear interactions in the accelerator＇s treatment head, patient＇s body, and treat- ment room ambient. electrons impinging on a heavy target generate a cascade shower of bremsstrahlung photons, the energy spectrum of which shows an end point equal to the electron beam energy. By varying the target thickness, an optimum thickness exists for which, at the given electron energy, maximum photon flux is achievable. If a source of high-energy photons i.e. bremsstrahlung, is conveniently directed to a suitable D20 target, a novel approach for production of an acceptable flux of filterable photoneturons for boron neutron capture therapy （BNCT） application is possible. This study consists of two parts. 1. Comparison and assessment of deuterium photonuclear cross section data. 2. evaluation of the heavy water photonuclear source.

关键词： BNCT photoneutron source linac heavy water

A Correlation Analysis of the Relationship between Land Use and Land Cover/Land Surface Temperature in Abuja municipal, FCT, Nigeria

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Journal of Geographic Information System 2019年第1期11卷 44-55页

作者： m. e. Awuh P. O. Japhets m. C. Officha A. O. Okolie I. C. enete Department of Geography & meteorology NAU Awka Nigeria Department of Architecture NAU Awka Nigeria Department of Architecture Chukwuemeka Odumegwu Ojukwu University Uli Nigeria

This study adopted Remote Sensing and GIS in assessing Land Use and Land Cover (LULC)/Land Surface Temperature (LST) variation in Abuja municipal, FCT from 1986 to 2016. The thirty-year study period was chosen with the specific objective to determine the relationship between LULC and LST using a correlation analysis. Three Landsat Tm/eTm+ images of the study area (1986, 2001 and 2016) were used to carry out the study. LULC was found to increase by 246.96 km2 (86.4%) in areal extent of built-up between 1986 and 2016;the spatial extent of the LST was found to increase on average from 23.5°C to 30.2°C. The correlation analysis showed a strong coefficient of determination (r2). The correlation analyses proved that the LULC classes were strongly related to LST. A strong correlation between the LULC classes and LST was observed at 0.8266, 0.9486, and 0.77 for 1986, 2001, and 2016. The coefficient of determination (r2) for 2016 was 0.77, being a strong indicator that a strong relationship existed implying that built-up areas were major drivers of the variation in the LST in Abuja municipal. To promote thermal comfort in Abuja municipal, urban planning, and control of building patterns tree-planting exercises are some of the recommendations made.

关键词： Correlation Analysis Remote Sensing Abuja LULC/LST Relationship

mapping of Aluminous Rich Laterite Depositions through Hyper Spectral Remote Sensing

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International Journal of Geosciences 2018年第2期9卷 93-105页

作者： m. J. Ratnakanth Babu e. N. Dhanamjaya Rao Lalitha Kallempudi Das Iswar Chandra Department of mines & Geology Government of Andhra Pradesh Vijayawada India Department of Geology Andhra University Visakhapatnam India Department of Geography Andhra University Visakhapatnam India National Remote Sensing Centre Hyderabad India

Increased dimensionality of the satellite data proves to be very useful for discriminating features with very close spectral matching. Present study concentrates on the retrieval of reflectance spectra from the level one radiometrically corrected data in Koraput district (Orissa) for the Bauxite ore. In the present study, atmospheric correction model FLAASH has been used to retrieve reflectance from the radiance data. Preprocessing of the dataset has been done before applying atmospheric correction on the dataset. Spectral subsetting of noise prone bands has been successfully done. Local destriping of the affected bands has been done using a 3*3 local mean filter. Spectral signatures of samples were derived from the processed data. Spectral signature of each sample and derived features vectors were correlated with the satellite image of the area and distribution of each feature was demarcated. Spatial abundance of each feature was used in preparation of mineral abundance map. Accuracy of the map was assessed using training sets of representative geological units. The mineral abundance mapping using the spectral analysis of the reflectance image involves the endmember collection using the N-Dimensional visualizer tool in eNVI software. Laterite, Bauxite, Iron and silica rich Aluminous laterite soil, Alluvium and Forest were selected as the end members after understanding the geology and analysis of the reflectance image. Various mapping techniques were applied to generate the final classified mineral abundance map, Linear Spectral Unmixing, mixture Tune matched Filtering, Spectral Feature Fitting, Spectral Angle mapper were the techniques used. Results have revealed the ability of Hyper spectral Remote sensing data for the identification and mapping of Hydrothermal altered products like Bauxite, Aluminous Laterite. This technology can be utilized for targeting minerals in the altered zone.

关键词： Hyperspectral Remote Sensing Aluminous Rich Laterite Imaging Spectroscopy Hydro Thermal Altered Ores

Prophylactic Wound Drainage in Orthopaedics: A Comparative evaluation of Closed Suction Drainage versus No-Drainage in a Nigerian Teaching Hospital

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Surgical Science 2013年第5期4卷 277-282页

作者： Ikpeme A. Ikpeme Ngim e. Ngim Iniabasi U. Ilori enembe Oku Anthony m. Udosen Departments of Anaesthesiology University of Calabar Teaching Hospital Calabar Nigeria Departments of Community medicine University of Calabar Teaching Hospital Calabar Nigeria Departments of Orthopaedics & Traumatology University of Calabar Teaching Hospital Calabar Nigeria

Background: Surgical wound drainage is practiced routinely by many orthopaedic surgeons despite studies that challenge the practice. Among proponents, the advantages of drainage include prevention of haematoma and/or seroma formation which potentially reduces the chances for infection, prevention of wound swelling, prevention of compartment syndrome and improvement of the local wound environment. Opponents argue that prophylactic wound drainage confers no significant advantages, increases the risk of infection and the need for blood transfusion with the attendant risks of this therapy. Aim: To ascertain if prophylactic drainage of clean orthopaedic wounds confer any significant advantages by evaluating wound and systemic factors in two treatment groups. Patients and methods: A prospective analysis of 62 patients was undergoing clean orthopaedic procedures. The patients were randomly assigned to a “No drain” (study) group and a “drain” (control) group. each group had 31 patients. Surgeons were blinded to the randomization process and the evaluation of clinical outcomes. The parameters assessed included pain, superficial wound infection, the need for post-operative transfusion, wound leakage, dressing changes and the surgery-discharge interval. Data was analysed using SPSS statistics version 20 (IBm Corp., New York). Results: There were no significant differences in the demographic data. Femoral fractures were the commonest indication for surgery (43.55%), and plate and screw osteosynthesis was the commonest procedure (48.4% in the drain group and 67.7% in the no-drain group). There was a significantly higher need for post-operative transfusion in the drain group (22.6% against 0%) as well as a significantly prolonged capillary refill time (2.39 + 0.56 secs versus 2.03 + 0.41 secs). Although not statistically significant, there were four cases (12.8%) of superficial wound infection in the drain group and 1 case (3.2%) in the no-drain group. Conclusion: Prophylactic wo

关键词： Wound Drain No-Drain Complications Orthopaedics