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文章速递Chordoma Sociodemographic, Clinical and Therapeutic Aspects in National Institute of Oncology Rabat Morocco: A Report of 9 Cases 认领
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作者 Gaël Kietga Patricia Agbanglanon +3 位作者 Bertrand Compaore Evrard Seka Amine Lachgar Noureddine Benjaafar 《癌症治疗(英文)》 2021年第1期47-56,共10页
<strong>Introduction:</strong> <span><span><span style="font-family:""><span style="font-family:Verdana;">Chordoma is a rare bone tumor, which develops main... <strong>Introduction:</strong> <span><span><span style="font-family:""><span style="font-family:Verdana;">Chordoma is a rare bone tumor, which develops mainly from the sacrum, the base of the skull, or the spine. Surgery + radiotherapy (if necessary) is the standard treatment. Data on chordoma are scarce in this re</span><span style="font-family:Verdana;">gion, and thus, here we summarized 9 patients with this tumor whom we</span><span style="font-family:Verdana;"> treated in this institute. </span><b><span style="font-family:Verdana;">Material: </span></b><span style="font-family:Verdana;">Nine chordoma patients were summarized, who were treated in National Institute of Oncology in Rabat between 2013 </span><span style="font-family:Verdana;">and 2018. We retrieved data from medical charts and analyzed the clinical</span><span style="font-family:Verdana;"> characteristics of this tumor. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">The average age was 49 years (range: 29 </span><span style="font-family:Verdana;">- 72), with male: female of 3:6. The manifestation-diagnosis time was 4</span><span style="font-family:Verdana;"> months (range: 2 - 14). Regarding the tumor location, lumbosacral spine;5, the skull;4. Mass was evident in 6. Signs of locoregional compressions (paraparesis or tetraparesis) were observed in 3. As for treatment, a partial tumor excision was performed in 8, with 3 patients undergoing a wide excision. Radiotherapy was done;3 patients with a dose of 46 Gy, 3 patients with 66 Gy, 1 patient with 50 Gy, and 1 patient with a 16 Gy gamma radio-knife in a single session. 4 patients with a dose of 46 Gy, 2 patients with 60 Gy, and 1 patient with a 16 Gy gamma radio-knife in a single session. Of 9, 4 patients had good locoregional control whereas 5 patients had local recurrence. </span><b><span style="font-family:Verdana;">Conclusion: </span></b><span style="font-family:Verdana;">Chordoma is a predominantly local aggressive tumor with low metastatic potential. The surgical excision remains the main prognostic factor. Advances in radiotherapy may improve local control. These data are of use in management of this tumor in Rabat (Morocco).</span></span></span></span> 展开更多
关键词 Chordoma Diagnosis Radiation Therapy Morocco
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文章速递Empirical Models for Predicting Global Solar Radiation on the African Continent Based on Factors of Location and Season 认领
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作者 Olabode M. Bamigbola Shola E. Atolagbe 《建模与仿真(英文)》 2021年第1期59-73,共15页
The importance of accurate knowledge about available global solar radiation in the design and development of various solar energy systems cannot be overemphasized. Most of the available models for predicting global so... The importance of accurate knowledge about available global solar radiation in the design and development of various solar energy systems cannot be overemphasized. Most of the available models for predicting global solar radiation involve a plethora of input factors, some of which require special skills and equipment to measure. Such multi-factor models are complex and computationally demanding. To remove some burdens associated with such models, the use of</span><span style="font-family:Verdana;"> simplified prototypes with reduced input factors ha</span></span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> been proposed. It has </span><span style="font-family:Verdana;">been </span><span style="font-family:Verdana;">shown that a model with fewer input factors, that can be determined in a definite manner or whose attributes are directly observable, is often a better alternative. Therefore, the main object of this paper is to have models with a few variables that can easily be measured, developed for predicting global solar radiation. Two input factors</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">geographical location and season of the year</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">were considered. Using a 22-year interannual average daily insolation data from the database of the National Aeronautics and Space Administration (NASA) blended with the art of interpolation, empirical models were fashioned with </span><span style="font-family:""><span style="font-family:Verdana;">the data for the five subregions of Africa. The results of the models’ analysis indicate that the latitude component is the dominant locational factor. Furthermore, the new models exhibit optimal performance in comparison with existing </span><span style="font-family:Verdana;">models</span><span style="font-family:Verdana;"> and constitute reliable predictive tools that are suitable for estimating global solar radiation for any practical application. 展开更多
关键词 Solar Radiation Modelling Empirical Data Prediction Interpolation
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文章速递红外辐射涂料在220 t/h锅炉上的运用 认领
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作者 胡龙光 《冶金动力》 2021年第1期44-47,共4页
在锅炉水冷壁管上喷涂高辐射远红外节能涂料,增加水冷壁的吸热能力,提高蒸汽量,同时也降低排烟温度,提高锅炉热效率,实现节能减排效果。
关键词 锅炉水冷壁 辐射 红外节能涂料
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文章速递核桃油脂转化期树下光环境的时空变化研究 认领
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作者 桑玉强 王若伦 +3 位作者 姜玉洁 路晓静 张劲松 施光耀 《河南科学》 2021年第1期52-58,共7页
以太行山南簏低丘山区5年生和10年生核桃为研究对象,利用ASD便携式光谱仪对核桃油脂转化期树下不同空间光强、光质及消减率进行测算,结果显示:①5、10 a核桃树下的光合有效辐射均在中午12:00达到最大值,在空间上表现为在距树2.5 m(树行... 以太行山南簏低丘山区5年生和10年生核桃为研究对象,利用ASD便携式光谱仪对核桃油脂转化期树下不同空间光强、光质及消减率进行测算,结果显示:①5、10 a核桃树下的光合有效辐射均在中午12:00达到最大值,在空间上表现为在距树2.5 m(树行中间)处最大,树行内西侧各处消减率均高于对应的东侧各处;5、10 a核桃树下光合有效辐射相对CK分别减少了60.12%和77.68%.②两种林龄核桃树下红外波段内各光质在时间和空间上均表现为远红外光比例>近红外光比例;光合有效辐射波段内各光质在日内不同时刻均表现为黄绿光比例>蓝紫光比例>红橙光比例,空间上5 a核桃树下各测点均表现为黄绿光比例>蓝紫光比例>红橙光比例,10 a核桃树下各测点黄绿光比例最大,距树1.5~2.5 m范围内表现为蓝紫光比例>红橙光比例,其余为红橙光比例>蓝紫光比例.其中蓝紫光在5 a和10 a均表现为消减率最大,且两种林龄核桃树下差异显著(P<0.05).不同林龄核桃树下不同时间、空间处的光环境各不相同,因此在生产实践中可根据树下光环境的差异选择适宜树下种植的作物. 展开更多
关键词 核桃 辐射 光照强度 光质 消减率
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Asymptotics for null-timelike boundary problems for general linear wave equations 认领
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作者 Qing Han Lin Zhang 《中国科学:数学英文版》 SCIE 2021年第1期111-128,共18页
We study the linear wave equation□gu=0 in Bondi-Sachs coordinates,for an asymptotically flat Lorentz metric g.We consider the null-timelike boundary problem,where an initial value is given on the null surfaceτ=0 and... We study the linear wave equation□gu=0 in Bondi-Sachs coordinates,for an asymptotically flat Lorentz metric g.We consider the null-timelike boundary problem,where an initial value is given on the null surfaceτ=0 and a boundary value on the timelike surface r=r0.We obtain spacetime Hp-estimates of ru for r>r0 and derive an asymptotic expansion of ru in terms of 1/r as r→∞. 展开更多
关键词 wave equations radiation field energy estimates asymptotic expansion
Efficacy and safety of intraoperative radiotherapy in rectal cancer:A systematic review and meta-analysis 认领
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作者 Bin Liu Long Ge +6 位作者 Jing Wang Ya-Qiong Chen Shi-Xun Ma Pei-Lan Ma Yun-Qiang Zhang Ke-Hu Yang Hui Cai 《世界胃肠肿瘤学杂志:英文版(电子版)》 SCIE CAS 2021年第1期69-86,共18页
BACKGROUND In recent years,intraoperative radiotherapy(IORT)has been increasingly used for the treatment of rectal cancer.However,the efficacy and safety of IORT for the treatment of rectal cancer are still controvers... BACKGROUND In recent years,intraoperative radiotherapy(IORT)has been increasingly used for the treatment of rectal cancer.However,the efficacy and safety of IORT for the treatment of rectal cancer are still controversial.AIM To evaluate the value of IORT for patients with rectal cancer.METHODS We searched PubMed,Embase,Cochrane Library,Web of Science databases,and conference abstracts and included randomized controlled trials and observational studies on IORT vs non-IORT for rectal cancer.Dichotomous variables were evaluated by odds ratio(OR)and 95%confidence interval(CI),hazard ratio(HR)and 95%CI was used as a summary statistic of survival outcomes.Statistical analyses were performed using Stata V.15.0 and Review Manager 5.3 software.RESULTS In this study,3 randomized controlled studies and 12 observational studies were included with a total of 1460 patients,who are mainly residents of Europe,the United States,and Asia.Our results did not show significant differences in 5-year overall survival(HR=0.80,95%CI=0.60-1.06;P=0.126);5-year disease-free survival(HR=0.94,95%CI=0.73-1.22;P=0.650);abscess(OR=1.10,95%CI=0.67-1.80;P=0.713),fistulae(OR=0.79,95%CI=0.33-1.89;P=0.600);wound complication(OR=1.21,95%CI=0.62-2.36;P=0.575);anastomotic leakage(OR=1.09,95%CI=0.59-2.02;P=0.775);and neurogenic bladder dysfunction(OR=0.69,95%CI=0.31-1.55;P=0.369).However,the meta-analysis of 5-year local control was significantly different(OR=3.07,95%CI=1.66-5.66;P=0.000).CONCLUSION The advantage of IORT is mainly reflected in 5-year local control,but it is not statistically significant for 5-year overall survival,5-year disease-free survival,and complications. 展开更多
关键词 Intraoperative radiotherapy Rectal cancer Systematic review External beam radiation therapy Randomized controlled trials META-ANALYSIS
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Beclin1介导的自噬在辐射诱导细胞早衰中的作用 认领
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作者 田雨汀 刘青杰 +1 位作者 田梅 高玲 《中国医学装备》 2021年第1期158-162,共5页
自噬是机体及细胞必不可少的调节过程,在维持细胞的正常生理状态过程中发挥重要的作用。Beclin1是自噬的核心功能基因之一,其影响自噬体形成,并通过自噬影响肿瘤的发生和发展。研究发现Beclin1在p62蛋白介导的早衰调控中发挥一定作用,... 自噬是机体及细胞必不可少的调节过程,在维持细胞的正常生理状态过程中发挥重要的作用。Beclin1是自噬的核心功能基因之一,其影响自噬体形成,并通过自噬影响肿瘤的发生和发展。研究发现Beclin1在p62蛋白介导的早衰调控中发挥一定作用,电离辐射可引起细胞发生自噬及早衰等细胞反应,导致细胞死亡。研究Beclin1介导的自噬在辐射诱导细胞早衰中的作用对肿瘤的放射治疗有重要意义,可为如何提高肿瘤细胞的放射治疗敏感性这一问题提供参考。综述Beclin1介导的自噬在辐射诱导细胞早衰中作用的相关研究进展,为Beclin1相关的肿瘤放射治疗的理论基础研究提供参考。 展开更多
关键词 BECLIN1 辐射 自噬 细胞早衰
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Irreversibility investigation of Casson fluid flow in an inclined channel subject to a Darcy-Forchheimer porous medium:a numerical study 认领
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作者 A.ROJA B.J.GIREESHA B.NAGARAJA 《应用数学和力学:英文版》 SCIE EI 2021年第1期95-108,共14页
The heat transfer and entropy generation characteristics of the magnetohydrodynamic Casson fluid flow through an inclined microchannel with convective boundary conditions are analyzed.Further,the effects of the viscou... The heat transfer and entropy generation characteristics of the magnetohydrodynamic Casson fluid flow through an inclined microchannel with convective boundary conditions are analyzed.Further,the effects of the viscous forces,Joule heating,heat source/sink,and radiation on the flow are taken into account.The non-dimensional transformations are used to solve the governing equations.Then,the reduced system is resolved by the fourth-fifth order Runge-Kutta-Fehlberg method along with the shooting technique.The effects of different physical parameters on the heat transfer and entropy generation are discussed in detail through graphs.From the perspective of numerical results,it is recognized that the production of entropy can be improved with the Joule heating,viscous dissipation,and convective heating aspects.It is concluded that the production of entropy is the maximum with increases in the Casson parameter,the angle of inclination,and the Hartmann number.Both the Reynolds number and the radiation parameter cause the dual impact on entropy generation. 展开更多
关键词 inclined channel Casson fluid MAGNETISM radiation entropy generation Bejan number
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医用一次性防护服γ辐照灭菌工艺研究 认领
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作者 崔磊 郭丽莉 +4 位作者 尹玉吉 王宏伟 王贵超 顾俊 祝军 《同位素》 CAS 2021年第1期1-9,I0001,共10页
2020年新型冠状病毒疫情在全世界爆发,在短期内需要大量一次性医用防护服,其中防护服的灭菌工艺是一个重要环节。医用一次性防护服若采用传统的环氧乙烷灭菌工艺需要至少7~14 d时间。γ辐照技术是一种可以对医用一次性防护服实施快速消... 2020年新型冠状病毒疫情在全世界爆发,在短期内需要大量一次性医用防护服,其中防护服的灭菌工艺是一个重要环节。医用一次性防护服若采用传统的环氧乙烷灭菌工艺需要至少7~14 d时间。γ辐照技术是一种可以对医用一次性防护服实施快速消毒灭菌的方法。因此,开展医用一次性防护服的辐照灭菌工艺研究有重要意义。选取两种典型的PET(聚对苯二甲酸乙二醇酯)材料的医用一次性防护服,一种有PU(聚氨酯)涂层,一种没有PU涂层。参考《医用一次性防护服辐照灭菌应急规范(临时)》和ISO 11137,分别进行生物负载实验。根据实验结果选择合适的方法建立灭菌剂量。使用苏州中核华东辐照有限公司BFTⅤ型γ辐照装置进行灭菌剂量验证。验证结果为满足无菌保证水平(SAL=10-6)的有PU涂层的防护服灭菌剂量为30.6 kGy,没有PU涂层的防护服灭菌剂量为30.8 kGy。对PET材料医用一次性防护服样品分别使用20.0 kGy、30.0 kGy和50.0 kGy的剂量辐照处理,材料断裂强力没有发生显著变化,且符合国家标准GB 19082-2009的相关要求。研究结果表明,对于以PET为主材的医用一次性防护服建立的γ辐照灭菌工艺有效,无菌保证水平为(SAL=10-6),同时对一次性防护服的辐照灭菌应用提出一些建议。 展开更多
关键词 辐照技术 医用一次性防护服 灭菌剂量
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银杏酮酯预处理减轻辐射所致模型小鼠的急性肠损伤 认领
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作者 左振魁 韩佳瑞 +1 位作者 计树灵 贺璐璐 《中国组织工程研究》 CAS 北大核心 2021年第23期3666-3671,共6页
背景:高剂量的胸部、骨盆、腹部和全身放疗均可能触发急性肠损伤。已有研究表明,银杏酮酯(GBE50)具有抗氧化和抗炎作用,而其对放疗性辐射导致急性肠损伤的作用尚不清楚。目的:探讨GBE50预处理对辐射导致的急性肠损伤的保护作用和机制。... 背景:高剂量的胸部、骨盆、腹部和全身放疗均可能触发急性肠损伤。已有研究表明,银杏酮酯(GBE50)具有抗氧化和抗炎作用,而其对放疗性辐射导致急性肠损伤的作用尚不清楚。目的:探讨GBE50预处理对辐射导致的急性肠损伤的保护作用和机制。方法:将27只小鼠随机分为对照组、辐射组、GBE50治疗组,每组9只。采用苏木精-伊红染色观察小肠的病理学改变;TUNEL染色评估隐窝和绒毛中细胞凋亡情况;免疫组化法检测小肠组织中Ki67、嗅质蛋白4和溶菌酶的表达和分布;Western blot法检测小肠组织中闭合蛋白1、闭合小环蛋白1和Lgr5的表达水平;采用试剂盒法检测小肠组织中丙二醛含量和超氧化物歧化酶活性。结果与结论:①与辐射组相比,GBE50预处理可显著减轻小鼠辐射引起的病理学改变和细胞凋亡,提高辐射后小肠干细胞的再生能力,减轻辐射引起的小鼠肠上皮屏障破坏和氧化应激反应;②结果表明,GBE50预处理可减轻辐射导致的小鼠急性肠损伤。 展开更多
关键词 银杏酮酯 辐射 放疗 急性肠损伤 细胞凋亡 隐窝 绒毛
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环氧化天然橡胶新型交联体系的研究进展 认领
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作者 宋维晓 罗锦标 +1 位作者 卢咏来 张立群 《橡胶工业》 CAS 2021年第1期73-78,共6页
介绍环氧化天然橡胶(ENR)新型交联体系,包括二胺/二酸类交联体系、不饱和羧酸金属盐交联体系、填料交联体系以及辐射交联体系等的研究现状及存在的问题,指出开发高效率、低成本和良好应用性能的新型交联体系是今后研究的重点方向。
关键词 环氧化天然橡胶 新型交联体系 二胺 二酸 不饱和羧酸金属盐 填料 辐射
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文章速递Prevention and treatment for radiation-induced skin injury during radiotherapy 认领
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作者 Yimin Wang Wenling Tu +1 位作者 Yiting Tanga Shuyu Zhang 《放射医学与防护》 2020年第2期60-68,共9页
The skin tissue has the largest area in the human body and functions as both a barrier and a defender.As such,it tends to be the first tissue to be damaged.Advances in medical technology provide prospects as well as s... The skin tissue has the largest area in the human body and functions as both a barrier and a defender.As such,it tends to be the first tissue to be damaged.Advances in medical technology provide prospects as well as side effects,for example,radiation therapy for cancer.With increasing cancer morbidity and radiation widely applied for cancer therapy,radiation-induced skin injury(RSI)has become a serious concern.In recent decades,research efforts have focused on the mechanisms underlying RSI.This review summarizes the mainstream opinions on these mechanisms,including the pathological,molecular biological,and cytobiological alterations.Radiationinduced reactive oxygen species(ROS),cytokines and involved signaling pathways are evaluated.Other relevant aspects include radiation-induced skin fibrosis(RSF)and radiation-related skin cell senescence.Moreover,we review strategies for the prevention and treatment in clinical and pre-clinical studies to support the treatment of RSI during radiotherapy.The prevention strategies include dose control,pre-irradiation instructions,and RSI assessments,while the main treatments include physical therapy,external-use dressings or creams,biological therapy and surgical reconstruction. 展开更多
关键词 Ionizing radiation Radiotherapy Radiation-induced skin injury(RSI) Radiation-induced skin fibrosis(RSF) Radiation-related skin cell senescence
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From Poincaré’s Electro-Gravific Ether (1905) to Cosmological Background Radiation (3°K, 1965) 认领
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作者 Yves Pierseaux 《现代物理(英文)》 2020年第9期1410-1427,共18页
<p align="justify"> <span style="font-family:Verdana;"></span><span style="font-family:Verdana;"></span>It is well known that Einstein published in June 1905... <p align="justify"> <span style="font-family:Verdana;"></span><span style="font-family:Verdana;"></span>It is well known that Einstein published in June 1905 his theory of Special Relativity (SR) without entirely based on space-time Lorentz Transformation (LT) with invariance of Light Velocity. It is much less known that Poincaré published, practically at the same time, a SR also based entirely on LT with also an invariant velocity. However, according to Poincaré, the invariant is not only that of light wave but also that of Gravific Wave in Ether. Poincaré’s Gravific ether exerts also a Gravific pressure, in the same paper, on <i>charged </i>(e) Electron (a “Hole in Ether” according to Poincaré). There are thus two SR: That of Einstein (ESR), without ether and without gravitation, and that of Poincaré (PSR), with Electro-Gravific-Ether. The crucial question arises then: Does “SPECIAL” Poincaré’s (e)-G field fall in the framework of Einstein’s GENERAL Relativity? Our answer is positive. On the basis of Einstein’s equation of gravitation (1917) with Minkowskian Metric (MM) and Zero Constant Cosmological (CC) we rediscover usual Static Vacuum (without <i>charge e </i>of electron). On the other hand with MM and <i>Non-Zero </i>CC, we discover the gravific field of a Cosmological Black Hole (CBH) with density of dark energy compatible with expanding vacuum. Hawking’s Stellar Black Hole (SBH) emits outgoing Black Radiation, whilst Poincaré’s CBH emits (at time zero) incoming Black Radiation. We show that Poincaré’s G-electron involves a (quantum) GRAVITON (on the model of Einstein’s quantum photon) underlying a de Broglie’s G-Wave. There is therefore a Gackground Cosmological model in Poincaré’s basic paper which predicts a density and a temperature of CBR very close to the observed (COBE) values. </p> 展开更多
关键词 Poincaré’s Special Relativity (PSR) with Gravitation PSR in Einstein’s GR with CC Poincaré’s Cosmological Black Hole Poincaré’s Incoming Cosmological Black Radiation versus Hawking’ s Outgoing Stellar Black Radiation Poincaré’s Gravitational Pressure on Electron (“Ge”) Vacuum without Charge e (ESR) Vacuum with Charge e (PSR) Lightlike Quantum Graviton
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Numerical Calculations for a Boundary Layer Flow past a Moving Vertical Porous Plate with Suction/Injection and Thermal Radiation 认领
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作者 Okey Oseloka Onyejekwe Yohannes Demiss Belete Nahom Alemseged Worku 《应用数学(英文)》 2020年第3期172-183,共12页
The work presented herein investigates the velocity, heat transfer, Nusselt number and skin friction profiles involved in boundary layer flow past a moving vertical porous plate. Similarity transformations are employe... The work presented herein investigates the velocity, heat transfer, Nusselt number and skin friction profiles involved in boundary layer flow past a moving vertical porous plate. Similarity transformations are employed to convert the governing nonlinear unsteady momentum and energy equations from their partial differential equation forms to boundary value ordinary differential equations. The resulting equations are then solved numerically by the Runge-Kutta fourth order method with the help of a shooting technique. Several features of the flow and heat transfer characteristics for different values of problem parameters are analyzed and discussed. These include the effects of the radiation parameter (R), suction and injection parameter (c), Grashof (Gr) and Prandtl (Pr) numbers on the flow and heat profiles. Numerical results show the impact of blowing and sucking as well as radation on boundary layer flows of this type. Both the skin frictions as well as the heat transfer rate are also significantly related to the radiation parameter. For all these cases;the numerical results are found to be in agreement with the physics of the problem. 展开更多
关键词 MOMENTUM and Energy Grashof NUMBER Prandtl NUMBER Similarity Transformation RADIATION Parameter SUCTION BLOWING RADIATION Po-rous Plate
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Impact of UVB Solar Radiation on Ambient Temperature for Kuwait Desert Climate 认领
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作者 Ibrahim M. Kadad Kandil M. Kandil Talal H. Alzanki 《智能电网与可再生能源(英文)》 2020年第8期103-125,共23页
<span style="font-family:Verdana;">This study examines the correlation between solar UVB and different weather parameters in Kuwait climate. To achieve that purpose, an experimental outdoor facility is... <span style="font-family:Verdana;">This study examines the correlation between solar UVB and different weather parameters in Kuwait climate. To achieve that purpose, an experimental outdoor facility is designed and set up at the College of Technological Studies, Kuwait for regular monitoring of solar global radiation, UVB radiation and ambient temperature in Kuwait from beginning of January 1</span><sup><span style="font-family:Verdana;">st</span></sup><span style="font-family:Verdana;"> 2014 until the end of December 2019. Outcomes reveal that the change of solar UVB as well as global radiation through the whole day inaugurate the same behavior for t</span><span style="font-family:Verdana;">he recorded data in clear day times. Statistical analysis is carried out to ob</span><span style="font-family:Verdana;">tain a correlation linking UVB radiation and both ambient temperature and </span><span style="font-family:Verdana;">global solar radiation. Regression analysis of the current work shows that ther</span><span style="font-family:Verdana;">e is a solid correlation among UVB radiation and both ambient temperature and g</span><span style="font-family:Verdana;">lobal solar radiation, especially for intermedia</span><span style="font-family:Verdana;">te to small global solar radiation ranges. In addition, UV index is evaluated for various months at all day times. It is important to record that UV index with the maximum values is attained in May-August months through midday period. Also, UV index values do not surpass the accepted extreme value which is higher than 9 during any time of the study period.</span> 展开更多
关键词 Ambient Temperature UVB Radiation Solar Radiation UV Index Relative Humidity
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Investigation of Natural Radioactivity and Dose Assessment over Steel Making Region 认领
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作者 Abdelazem E. A. Mohamed Mohammed A. Halato Siddig T. Kafi 《生态学期刊(英文)》 2020年第7期397-403,共7页
This study aims to measure the radiation dose over several steel-making factories in Khartoum region, Sudan. The authors used different techniques to detect the harmful Natural Occurring Radioactive Material (NORM) em... This study aims to measure the radiation dose over several steel-making factories in Khartoum region, Sudan. The authors used different techniques to detect the harmful Natural Occurring Radioactive Material (NORM) emitting through the steel-making process. While, an X-ray Diffractometer was utilized to detect the NORM in the isotopes clay elite and magnesio-ferrite over slag steel waste and soil. The worker dose was measured by using polimaster device and it was detected 56.448 mSv per year. And backpack mobile monitored the background over the waste and it was 0.048 μSv/h in accounting mode. In another hand gamma spectrometer with a high purity germanium detector detected the average of activity concentration of natural radionuclide over the slag steel waste and K-40 of it is 321 ± 3 Bq/Kg, Th-232 is 20.6 ± 5 Bq/Kg, Ra-226 is 15.2 ± 4 bq/Kg, Cs-137 is 3.33 ± 7 Bq/Kg, and over soil around the waste the concentration of K40, Ra226, Th232 was (185 ± 3, 12.6 ± 7, and 12.0 ± 5) Bq/Kg, respectively. 展开更多
关键词 Steel Making Slag Steel NORM Radiation Dose Radiation Survey
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World-Universe Model—Alternative to Big Bang Model 认领
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作者 Vladimir S. Netchitailo 《高能物理(英文)》 2020年第1期133-158,共26页
This manuscript provides a comparison of the Hypersphere World-Universe Model (WUM) with the prevailing Big Bang Model (BBM) of the Standard Cosmology. The performed analysis of BBM shows that the Four Pillars of the ... This manuscript provides a comparison of the Hypersphere World-Universe Model (WUM) with the prevailing Big Bang Model (BBM) of the Standard Cosmology. The performed analysis of BBM shows that the Four Pillars of the Standard Cosmology are model-dependent and not strong enough to support the model. The angular momentum problem is one of the most critical problems in BBM. Standard Cosmology cannot explain how Galaxies and Extra Solar systems obtained their substantial orbital and rotational angular momenta, and why the orbital momentum of Jupiter is considerably larger than the rotational momentum of the Sun. WUM is the only cosmological model in existence that is consistent with the Law of Conservation of Angular Momentum. To be consistent with this Fundamental Law, WUM discusses in detail the Beginning of the World. The Model introduces Dark Epoch (spanning from the Beginning of the World for 0.4 billion years) when only Dark Matter Particles (DMPs) existed, and Luminous Epoch (ever since for 13.8 billion years). Big Bang discussed in Standard Cosmology is, in our view, transition from Dark Epoch to Luminous Epoch due to Rotational Fission of Overspinning Dark Matter (DM) Supercluster’s Cores. WUM envisions Matter carried from the Universe into the World from the fourth spatial dimension by DMPs. Ordinary Matter is a byproduct of DM annihilation. WUM solves a number of physical problems in contemporary Cosmology and Astrophysics through DMPs and their interactions: Angular Momentum problem in birth and subsequent evolution of Galaxies and Extrasolar systems—how do they obtain it;Fermi Bubbles—two large structures in gamma-rays and X-rays above and below Galactic center;Diversity of Gravitationally-Rounded Objects in Solar system;some problems in Solar and Geophysics [1]. WUM reveals Inter-Connectivity of Primary Cosmological Parameters and calculates their values, which are in good agreement with the latest results of their measurements. 展开更多
关键词 Big Bang MODEL Four Pillars of Standard Cosmology ANGULAR MOMENTUM Problem Black Holes Hypersphere World-Universe MODEL Multicomponent DARK MATTER Macroobjects Structure Law of Conservation of ANGULAR MOMENTUM Medium of the World Inter-Connectivity of Primary Cosmological Parameters The Beginning of the World DARK EPOCH Rotational Fission Luminous EPOCH Macroobject Shell MODEL DARK MATTER Core Gravitational Burst Intergalactic Plasma Microwave Background Radiation Far-Infrared Background Radiation Emergent Phenomena CODATA
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Occupational Eye Lens Radiation Dose While Performing Interventional Procedures over 18 Months Using a Face-Shield Equipped Suspended Radiation Protection System 认领
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作者 Thomas J. Kwarcinski Andrew Lichliter +3 位作者 Joseph Oros Niraj KC Bryan Yoder Chet R. Rees 《放射学期刊(英文)》 2020年第2期101-114,共14页
<strong>Background: </strong>Numerous studies have demonstrated increasing evidence for cataractogenesis at lower levels of ionizing radiation than previously believed, with some suggesting possible absenc... <strong>Background: </strong>Numerous studies have demonstrated increasing evidence for cataractogenesis at lower levels of ionizing radiation than previously believed, with some suggesting possible absence of a threshold. Genetic differences between individuals also result in increased susceptibility in some operators, who might not be aware. European occupational exposure limits have been reduced and operators are seeking protective measures. <strong>Objective: </strong>To evaluate the protective effect of a face-shield equipped suspended protection system (Zero-Gravity<span style="white-space:nowrap;"><sup><span style="white-space:nowrap;">&reg;</span></sup></span>, TIDI Products, Neenah, WI) along with adherence to safety practices against radiation dose to the eye lens for an interventional radiologist performing a wide variety of procedures. <strong>Materials and Methods:</strong> In this institutional review board-approved single-institution study, one interventional radiologist wore a highly sensitive personnel monitoring dosimeter badge on the cap near the left eye while performing 299 procedures (3690 fluoroscopy minutes) over 18 consecutive months while utilizing the suspended protection system along with adherence to other generally recommended safety practices and movement away from the field during angiographic power injections. Dosimetry reports and procedural information were retrospectively reviewed. <strong>Results: </strong>Total lens dose equivalent to the left eye over 18 months was 0.11 mSv (annualized dose = 0.073 mSv, or 7.3 mRem). The patient-dose-area product standardized dose of 0.00576 <span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&mu;</span></span></span>Sv/Gy<span style="white-space:nowrap;"><span style="white-space:nowrap;">&sdot;</span></span>cm<sup>2</sup> is well below reports of conventional lead aprons, shields, and protective eyewear. <strong>Conclusion: </strong>Eye exposures were kept to near-background levels using the 展开更多
关键词 Lens Dose Reduction Radiation Safety Radiation-Induced Cataractogenesis Suspended Protection System
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World-Universe Model Predictions 认领
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作者 Vladimir S. Netchitailo 《高能物理(英文)》 2020年第2期282-297,共16页
In 2013, World-Universe Model (WUM) proposed a principally different way to solve the problem of Newtonian Constant of Gravitation measurement precision. WUM revealed a self-consistent set of time-varying values of Pr... In 2013, World-Universe Model (WUM) proposed a principally different way to solve the problem of Newtonian Constant of Gravitation measurement precision. WUM revealed a self-consistent set of time-varying values of Primary Cosmological parameters of the World: Gravitation parameter, Hubble’s parameter, Age of the World, Temperature of the Microwave Background Radiation, and the concentration of Intergalactic plasma. Based on the inter-connectivity of these parameters, WUM solved the Missing Baryon problem and predicted the values of the following Cosmological parameters: gravitation G, concentration of Intergalactic plasma, relative energy density of protons in the Medium, and the minimum energy of photons, which were experimentally confirmed in 2015-2018. Between 2013 and 2018, the relative standard uncertainty of G measurements decreased x6. The set of values obtained by WUM was recommended for consideration in CODATA Recommended Values of the Fundamental Physical Constants 2014. 展开更多
关键词 World-Universe Model DIMENSIONLESS Time-Varying PARAMETER Q Gravitational PARAMETER Hubble’s PARAMETER Age of the World TEMPERATURE of Microwave BACKGROUND RADIATION TEMPERATURE of FAR-INFRARED BACKGROUND RADIATION Peak Medium of the World Inter-Connectivity of Primary Cosmological Parameters Multicomponent Dark Matter Weak Interaction Intergalactic Plasma Neutrinos CODATA
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文章速递Research progress on biodosimeters of ionizing radiation damage 认领
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作者 Changyan Xiao Ningning He +2 位作者 Yang Liu Yan Wang Qiang Liu 《放射医学与防护》 2020年第3期127-132,共6页
Ionizing radiation can cause radiation injury to the human body under certain circumstances,such as unexpected radiation accidents and nuclear terrorist attacks.Methods that can accurately and rapidly measure the biol... Ionizing radiation can cause radiation injury to the human body under certain circumstances,such as unexpected radiation accidents and nuclear terrorist attacks.Methods that can accurately and rapidly measure the biological effects are necessary for rational triage and treatment of affected patients.In recent decades,significant researches attention has been focused on the development of accurate and efficient biodosimeters.In this review,we summarize recent developments in biological dosimeters,with a primary focus on cell-based and molecular markers,including comet assay,dicentric chromosome aberration,γ-H2AX,micronuclei,microRNA,lncRNA,and 8-Oxo-dG. 展开更多
关键词 Ionizing radiation Radiation injury Biodosimeter Comet assay Dicentric chromosome aberration γ-H2AX Micronuclei microRNA lncRNA 8-Oxo-dG
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