检索结果-南通市图书馆

Establishment of a calibration curve for an isocentric cobalt unit using Monte Carlo simulation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2017年第9期28卷 21-24页

作者： Seyed Milad vahabi Mojtaba Shamsaie-Zafarghandi Department of Energy Engineering and Physics Amirkabir University of Technology 424 Hafez Ave P.O. Box 15875-4413 Tehran Iran

Measurement of dose distribution in patients during radiotherapy is impossible. The Monte Carlo simulation is an alternative method for dose calculations. In routine radiotherapy, the source-to-surface distance(SSD)method is not practical for an isocentric unit because it requires numerous values of tissue–air ratios and inverse square law. Therefore, this method is time consuming. In this paper, the curves of relative depth doses were obtained for three different SSDs using the MCNP4C Monte Carlo simulation and approximated with a single curve called calibration curve. This curve was compared to the curve obtained by published data, differing in approximately 5% in the worst case. It was also observed that the obtained results were more accurate for distances between-5 and 10 cm from source-to-axis distance.

关键词：校准曲线蒙特卡罗模拟蒙特卡洛模拟单位平方反比定律剂量分布放射治疗剂量计算

Compensation of stress intensity factors in hollow cylinders containing several cracks under torsion by electro-elastic coating

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2019年第9期40卷 1335-1360页

作者： M. KARIMI A. GHASSEMI A. ATRIAN M. vahabi Department of Mechanical Engineering Najafabad Branch Islamic Azad University Najafabad Iran Modern Manufacturing Technologies Research Center Najafabad Branch Islamic Azad University Najafabad Iran

In this article, a formulation for a hollow cylinder reinforced with an electroelastic layer is investigated. The hollow cylinder and its electro-elastic coating are under the Saint-Venant torsional loading. First, the solution to the problem containing a Volterra-type screw dislocation is obtained by using the Fourier transform. The problem is then reduced to a set of Cauchy singular integral equations by the distributed dislocation method. Finally, several examples are presented to show the effect of the electro-elastic coating on the reduction of the stress intensity factors at the crack tips.

关键词： hollow cylinder electro-elastic coating stress intensity factor multiple arbitrarily oriented cracks Saint-Venant torsion electric displacement

Potential habitat modeling for reintroduction of three native plant species in central Iran

在线全文

学校读者我要写书评

暂无评论

journal of Arid Land 2015年第3期7卷 381-390页

作者： Elham G ARDESTANI Mostafa TARKESH Mehdi BASSIRI Mohammad R vahabi Department of Natural Resources Isfahan University of Technology

Potential habitat modeling of endemic species is an appropriate method to maintain biodiversity,ecosystem function and rehabilitation of rangeland *** caragana,*** and *** are endemic in Iran＇s rangelands and some neighboring *** three native species could endure environmental stresses due to their distinctive ecophysiological *** play important roles in sustainable pastures production,recreation and *** suffer severe threat from many factors including;grazing,agriculture and invasive exotic *** analyzed the potential habitat of three native plant species in central Iran basing on the grid map with the resolution of *** used inventory records from field surveys,herbarium collections and 22 environmental factors to explore the environmental influences on given species distribution by Maximum entropy（Maxent） *** is a species distribution model that uses species occurrence and environmental data for predicting potential *** results of our study indicated species occurrence has strong correlation with environmental factors such as mean temperature of wettest season,elevation and precipitation of coldest *** evaluated the model accuracy by AUC（area under the receiver operating characteristic curve） based on an independent test data *** values indicated the high power of Maxent to create potential habitat map（***=0.988,***=0.927,***=0.923）.It is important to consider that AUC values tend to be lower for species that have broad distribution scope,such as *** *** suitable potential habitat distributions of the three species were predicted in the western and southwestern parts of rangelands in Isfahan *** comparisons of the actual distribution map of the three species with produced Maxent maps represent a good *** general,the model demonstrated that the occurrence of the given species

关键词： Astragalus caragana Astragalus cyclophyllon Astragalus podolobus environmental factors Maxent

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher j.O’Connell Matthew j.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA james L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

The 2015 Migratory Crisis:The Disillusion of Visiting Rights

在线全文

学校读者我要写书评

暂无评论

Cultural and Religious Studies 2018年第1期6卷 62-71页

作者： Nader vahabi CADIS EHESS (School of Advanced Studies in Social Sciences) University of Toulouse(LISST) France

What has really happened in Europe since 2014?Why in 2018 are so many migrants still making their way towards Europe?For the first time since the Second World War,an important number of individuals have entered into European *** idea for this article goes back to October 2015 when the prefet from the town where I live went in search of asylum *** is what sparked off my inquiry amongst about 50 exiles housed in the annex of the Montmorency(95)hospital in july *** against popular belief,migrants are not accepted fairly into countries,and the geographical distribution of Syrians in Turkey,Lebanon,jordan,and Europe is contrary to what Kant had defended as a“right to visit”.Although the majority of researchers suggest welcoming migrants,it is necessary to reconsider some methodological and epistemological aspects and get away from some wrongly perceived concepts which dated prior to the year ***,the Arab Spring has showed that we are dealing with unfinished post-colonialism,something that we will soon come back to in another article where we will propose another solution.

关键词： migratory crisis visiting rights Kant trajectory post-colonialism

The Origin of the Different Waves of Iranian Migration in France

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cultural and Religious Studies 2016年第8期4卷 469-487页

作者： Nader vahabi School of Advanced Studies in Social Sciences (CADIS) in Paris University of Toulouse (Rural Dynamics) France

From the knowledge exile of the 19th century, the profile changed towards the political refugee in 1908. French was then recognized as the official language in administration. Iranian migration later took on another dimension after the 1953 Coup, a politicization that reached a peak with the arrival in Paris of Khomeini on August 2, 1978. In spite of this migratory tradition, about 4,000 persons before the revolution, the majority being from the political and financial elite, these migratory flows amplified in the middle of the 1980s, in such a way that at the end of December 2014, there were 31,000 Iranians in France. This new phase which included four waves, from a sociological point of view, can be called the diasporaisation of Iranian migration. The socio-economic profile goes from the urban elite： lawyers, officials, journalists, teachers, doctors, nurses, magistrates, military officials, company directors, political exiles, etc., to artisans such as shopkeepers, garage owners, building contractors.., and finally from the skilled labourer, on through to unskilled workers in building, restauration or removals,

关键词： Iranian diaspora migratory flows four waves of migration socio-economic profile

Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha j.Holdsworth Alistair j.Gunn Laura Bennet Hamid Abbasi Mātai Medical Research Institute Tairāwhiti GisborneNew Zealand Department of Anatomy&Medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand Center for Brain Research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia

Gene therapy for spinal muscular atrophy:perspectives on the possibility of optimizing SMN1 delivery to correct all neurological and systemic perturbations

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第7期20卷 2011-2012页

作者： Sharon j.Brown Rafael j.Yáñez-Muñoz Heidi R.Fuller School of Pharmacy and Bioengineering Keele UniversityKeeleUK Wolfson Center for Inherited Neuromuscular Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular atrophy(SMA)is a genetic condition that results in selective lower motor neuron loss with concomitant muscle weakness and *** genetic cause of SMA was understood in 1995 when loss or impairment of the survival motor neuron 1(SMN1)gene was identified as the main contributing factor(Lefebvre et al.,1995).This,in combination with the discovery that humans have a“back-up”gene,SMN2,which can produce low levels(approximately 10%)of the full-length functional SMN protein,has led to the generation of SMA-specific gene *** was traditionally classified according to age of symptom onset and developmental milestones achieved,with life expectancy and severity varying between ***,SMN2 copy number is used as a proxy for the prediction of disease severity,with higher SMN2 copy number typically being associated with reduced severity of SMA,although this relationship is not absolute:some individuals with low SMN2 copy number have less severe SMA phenotypes and vice ***,the etiology of SMA is further complicated by other factors,such as non-typical nucleotide variants and SMN2-independent modifiers of disease severity.

关键词： atrophy traditionally absolute

Women in visual neural regeneration research

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第2期20卷 489-490页

作者： Tonia S.Rex David j.Calkins Vanderbilt Eye Institute Vanderbilt University Medical CenterNashvilleTNUSA

The year 2024 marks the 60^(th)anniversary of Title IX and 25 years since the New York Times revealed bias against female faculty members at the Massachusetts Institute of *** take an opportunity here to examine the state of gender bias in a relatively new yet already prominent field,neural regeneration in the visual system,for which there is a well-defined context useful for this *** National Eye Institute(NEI)provided the first round of research funding for its Audacious Goals Initiative(AGI)on visual neural regeneration in 2013 and the last round in ***,we focus on this *** sources included PubMed,the National Science Foundation(NSF),the NEI,the Blue Ridge Institute for Medical Research and data from the major professional organization for eye and vision research,the Association for Research in Vision and Ophthalmology(ARVO).

关键词： neural visual Times