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1Review of magnesium-based biomaterials and their applications显示文摘In biomedical applications,the conventionally used metallic materials,including stainless steel,Co-based alloys and Ti alloys,often times exhibit unsatisfactory results such as stress shielding and metal ion releases.Secondary surgical operation(s)usually become inevitable to prevent long term exposure of body with the toxic implant contents.The metallic biomaterials are being revolutionized with the development of biodegradable materials including several metals,alloys,and metallic glasses.As such,the nature of metallic biomaterials are transformed from the bioinert to bioactive and multi-biofunctional(anti-bacterial,anti-proliferation,anti-cancer,etc.).Magnesium-based biomaterials are candidates to be used as new generation biodegradable metals.Magnesium(Mg)can dissolve in body fluid that means the implanted Mg can degrade during healing process,and if the degradation is controlled it would leave no debris after the completion of healing.Hence,the need for secondary surgical operation(s)for the implant removal could be eliminated.Besides its biocompatibility,the inherent mechanical properties of Mg are very similar to those of human bone.Researchers have been working on synthesis and characterization of Mg-based biomaterials with a variety of composition in order to control the degradation rate of Mg since uncontrolled degradation could result in loss of mechanical integrity,metal contamination in the body and intolerable hydrogen evolution by tissue.It was observed that the applied methods of synthesis and the choice of components affect the characteristics and performance of the Mg-based biomaterials.Researchers have synthesized many Mg-based materials through several synthesis routes and investigated their mechanical properties,biocompatibility and degradation behavior through in vitro,in vivo and in silico studies.This paper is a comprehensive review that compiles,analyses and critically discusses the recent literature on the important aspects of Mg-based biomaterials.Nurettin Sezer Zafer Evis Said Murat Kayhan Aydin Tahmasebifar Muammer Koça 2018Journal of Magnesium and Alloys2018,6,1:38
2Prevalence of and risk factors for gallstones in Uighur and Han Chinese显示文摘AIM:To perform a single-centre survey of the prevalence of and possible risk factors for gallstones in Uighur and Han Chinese.METHODS:Complete medical data for 9455 patients were collected from the medical centre of our hospital,and the overall prevalence of gallstones as well as the prevalence in different ethnic groups was studied.The risk factors for gallstones in different ethnic groups were identified in a univariate analysis,and variables with statistical significance were analysed by unconditional multiple logistic regression,to primarily explore the similarities and differences in gallstone risk factors between different ethnic groups.RESULTS:The prevalence of gallstones was significantly higher in the Uighur population than in the Hanpopulation(22.87%vs 11.64%,P<0.05).Further analysis of risk factors for gallstones based on the different ethnic areas revealed that age was a risk factor for gallstones in both groups;triglycerides,body-mass index(BMI)and high-density lipoprotein were risk factors for gallstones in the Han population,while total cholesterol(TC),gender and fatty liver were risk factors in the Uighur population.The Uighur patients were older than the Han patients,and had higher BMI,TC,low-density lipoprotein,female rate and fatty liver rate,while the incidence of hypertension was lower than that in the Han patients.CONCLUSION:The prevalence of and risk factors for gallstones differ between the Uighur and Han populations.Li Zhu Aikebaier Aili Cheng Zhang Aili Saiding Kelimu Abudureyimu Xinjiang Medical University 2014World Journal of Gastroenterology2014,20,40:39
3An overview of occult hepatitis B virus infection显示文摘Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our understanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome.Zeinab Nabil Ahmed Said 2011World Journal of Gastroenterology2011,17,15:20
4CXCL5/CXCR2 axis in tumor microenvironment as potential diagnostic biomarker and therapeutic target显示文摘The components of the tumor microenvironment(TME)in solid tumors,especially chemokines,are currently attracting much attention from scientists.C-X-C motif chemokine ligand 5(CXCL5)is one of the important chemokines in TME.Over-expression of CXCL5 is closely related to the survival time,recurrence and metasta-sis of cancer patients.In TME,CXCL5 binds to its receptors,such as C-X-C motif chemokine receptor 2(CXCR2),to participate in the recruitment of immune cells and promote angiogenesis,tumor growth,and metastasis.The CXCL5/CXCR2 axis can act as a bridge between tumor cells and host cells in TME.Blocking the trans-mission of CXCL5/CXCR2 signals can increase the sensitivity and effectiveness of immunotherapy and slow down tumor progression.CXCL5 and CXCR2 are also regarded as biomarkers for predicting prognosis and molecular targets for customiz-ing the treatment.In this review,we summarized the current literature regarding the biological functions and clinical significance of CXCL5/CXCR2 axis in TME.The possibility to use CXCL5 and CXCR2 as potential prognostic biomarkers and thera-peutic targets in cancer is also discussed.Wen Zhang Huishan Wang Mingyang Sun Xueting Deng Xueru Wu Yilan Ma Mengjing Li Said Maisam Shuoa Qiang You Lin Miao 2020Cancer Communications2020,40,2:19
5Current characteristics of congenital coronary artery fistulas in adults:A decade of global experience显示文摘AIM:To describe the characteristics of coronary artery fistulas(CAFs) in adults,including donor vessels and whether termination was cameral or vascular. METHODS:A PubMed search was performed for articles between 2000 and 2010 to describe the current characteristics of congenital CAFs in adults.A group of 304 adults was collected.Clinical data,presentations,diagnostic modalities,angiographic fistula findings and treatment strategies were gathered and analyzed.With regard to CAF origin,the subjects were tabulated into unilateral,bilateral or multilateral fistulas and compared.The group was stratified into two major subsets according to the mode of termination;coronary-cameral fistulas(CCFs) and coronary-vascular fistulas(CVFs) . A comparison was made between the two subsets. Fistula-related major complications[aneurysm formation,infective endocarditis(IE) ,myocardial infarction(MI) ,rupture,pericardial effusion(PE) and tamponade] were described.Coronary artery-ventricular multiple micro-fistulas and acquired CAFs were excluded as well as anomalous origin of the coronary arteries from the pulmonary artery(PA) . RESULTS:A total of 304 adult subjects(47%male) with congenital CAFs were included.The mean age was51.4 years(range,18-86 years) ,with 20%older than 65 years of age.Dyspnea(31%) ,chest pain(23%) and angina pectoris(21%) were the prevalent clinical presentations.Continuous cardiac murmur was heard in 82%of the subjects.Of the applied diagnostic modalities,chest X-ray showed an abnormal shadow in 4%of the subjects.The cornerstone in establishing the diagnosis was echocardiography(68%) ,and conventional contrast coronary angiography(97%) .However,multislice detector computed tomography was performed in 16%.The unilateral fistula originated from the left in 69%and from the right coronary artery in 31%of the subjects.Most patients(80%) had unilateral fistulas,18%presented with bilateral fistulas and 2%with multilateral fistulas.Termination into the PA was reported in unilateral(44%) ,bilateral(73%) and multilateral(75%) fistulas.Fistulas with multiple origins(bilateral and multilateral) terminated more frequently into the PA(29%) than into other sites(10.6%)(P=0.000) . Aneurysmal formation was found in 14%of all subjects.Spontaneous rupture,PE and tamponade were reported in 2%of all subjects.In CCFs,the mean age was 46.2 years whereas in CVFs mean age was 55.6 years(P=0.003) .IE(4%) was exclusively associated with CCFs,while MI(2%) was only found in subjects with CVFs.Surgical ligation was frequently chosen for unilateral(57%) ,bilateral(51%) and multilateral fistulas(66%) ,but percutaneous therapeutic embolization(PTE) was increasingly reported(23%,17%and 17%,respectively) . CONCLUSION:Congenital CAFs are currently detected in elderly patients.Bilateral fistulas are more frequently reported and PTE is more frequently applied as a therapeutic strategy in adults.Salah AM Said 2011World Journal of Cardiology2011,3,8:17
6蚜小蜂和粉虱座壳孢对烟粉虱的控制作用研究显示文摘研究了烟粉虱两种寄生性天敌桨角蚜小蜂 (Eretmocerussp .)和粉虱座壳孢 (Aschersoniaaley rodis)单独使用和联合使用时对烟粉虱种群的控制作用 .结果表明 ,在单独进行控制时 ,在一个世代内按 5× 10 6个孢子·ml-1喷施粉虱座壳孢 2次 ,对烟粉虱种群的控制作用达 95 .74 % ,按每株植株 3头雌蜂的密度释放桨角蚜小蜂 2次 ,对烟粉虱种群的控制作用达 5 7.5 8% .在两者联合控制时 ,一个世代内喷施粉虱座壳孢 2次 ,再释放桨角蚜小蜂 1次或 2次 ,对烟粉虱种群的控制作用达 97.0 2 %~ 97.91% ,烟粉虱种群增长趋势指数低于 1,种群数量逐渐下降 .联合使用时 ,桨角蚜小蜂和粉虱座壳孢间无消极影响 .邱宝利 任顺祥 肖燕 Nasser Said Mandour 2003应用生态学报2003,14,12:17
7Non-alcoholic fatty liver disease and liver transplantation:Outcomes and advances显示文摘Non-alcoholic fatty liver disease(NAFLD)is one of the most prevalent causes of chronic liver disease worldwide.In the last decade it has become the third most common indication for liver transplantation in the United States.Increasing prevalence of NAFLD in the general population also poses a risk to organ donation,as allograft steatosis can be associated with non-function of the graft.Post-transplant survival is comparable between NAFLD and non-NAFLD causes of liver disease,although long term outcomes beyond 10 year are lacking.NAFLD can recur in the allograft frequently although thus far post transplant survival has not been impacted.De novo NAFLD can also occur in the allograft of patients transplanted for non-NAFLD liver disease.Predictors for NAFLD post-transplant recurrence include obesity,hyperlipidemia and diabetes as well as steroid dose after liver transplantation.A polymorphism in PNPLA3 that mediates triglyceride hydrolysis and is linked to pre-transplant risk of obesity and NAFLD has also been linked to post transplant NAFLD risk.Although immunosuppression side effects potentiate obesity and the metabolic syndrome,studies of immunosuppression modulation and trials of specific immunosuppression regimens post-transplant are lacking in this patient population.Based on pre-transplant data,sustained weight loss through diet and exercise is the most effective therapy for NAFLD.Other agents occasionally utilized in NAFLD prior to transplantation include vitamin E and insulin-sensitizing agents.Studies of these therapies are lacking in the post-transplant population.A multimodality and multidisciplinary approach to treatment should be utilized in management of post-transplant NAFLD.Adnan Said 2013World Journal of Gastroenterology2013,19,48:15
8藏北高原草甸土壤固碳微生物群落特征随海拔和季节的变化显示文摘研究土壤固碳微生物丰度、群落结构、多样性差异及其影响因子对了解青藏高原土壤碳循环和固碳潜力具有重要意义。采用定量PCR(qPCR)、末端限制性片段分析(T-RFLP)、克隆文库和测序方法,研究了青藏高原草甸土壤固碳微生物丰度与群落结构随海拔和季节的变化,主要结果如下:1)随海拔升高高寒草甸土壤固碳微生物丰度显著升高,但季节变化不明显,不同类别微生物固碳基因cbbL丰度依次为:Form IC>Form IAB>Form ID,其中Form IC类固碳微生物可达10~8拷贝数/g土壤,cbbL基因丰度与海拔、土壤含水量和铵态氮含量(NH_4^+-N)呈正相关关系,与土壤温度和pH值负相关;2)固碳微生物多样性和丰富度随海拔升高而升高,在4800m达到最大,且二者受季节影响较小,其群落结构随海拔升高而逐渐变化,主要受土壤pH值、海拔和土壤水分影响;3)Form IC类固碳微生物主要包括放线菌门和和变形菌门,其中α变形菌门是高寒草甸土壤优势固碳微生物类群。本研究有助于理解土壤微生物群落功能及其在土壤碳循环过程中的作用,为更准确评估高寒草甸土壤碳循环过程提供了科学依据。高静 Said Muhanmmad 岳琳艳 何永涛 斯确多吉 张宪州 孔维栋 2018生态学报2018,38,11:14
9Epidemic of non-alcoholic fatty liver disease and hepatocellular carcinoma显示文摘Non-alcoholic fatty liver disease(NAFLD) associated hepatocellular carcinoma(HCC) incidence is increasing worldwide, paralleling the obesity epidemic. Although most cases are associated with cirrhosis, HCC can occur without cirrhosis in NAFLD. Diabetes and obesity are associated risk factors for HCC in patients. Given the sheer magnitude of the underlying risk factors(diabetes, obesity, non-cirrhotic NAFLD) screening for HCC in the non-cirrhotic population is not recommended. Optimal screening strategies in NAFLD cirrhosis are not completely elucidated with Ultrasound having significant limitations in detection of liver lesions in the presence of obesity and steatosis. Consequently NAFLD-HCC is more often diagnosed at a later stage with larger tumors and reduced opportunities for curative treatments as opposed to HCC in other causes of cirrhosis. When HCC is found at a curative stage treatments including liver transplantation, resection and loco-regional therapies are associated with good results similar to that seen in HCV-HCC. Future strategies under study include the use of chemopreventive and antioxidant agents to reduce development of cirrhosis and non-alcoholic steatohepatitis(NASH). Strategies to reverse NASH via weight loss, control of associated conditions like diabetes are key strategies in reducing the increasing incidence of NASH-HCC. Novel therapeutic agents for NASH are in trials and if successful in achieving reversal of NASH will be an important strategy in reducing NAFLD-HCC.Adnan Said Aiman Ghufran 2017World Journal of Clinical Oncology2017,8,6:13
10菜豆荚斑驳病毒的RT-PCR检测显示文摘菜豆荚斑驳病毒是对大豆经济具有重要影响的病毒。根据已报道的菜豆荚斑驳病毒外壳蛋白基因序列,设计出一对特异性引物,采用RT-PCR法,可有效地扩增出BPMV不同亚组的4个分离物,得到650 bp大小的PCR产物。这种方法能成功地检测出大豆病叶中的BPMV,结果和酶联检测是一致的,而对大豆种皮中BPMV的检测效果不佳,建议采用酶联的方法进行检测。魏梅生 相宁 张春泉 Said A.Ghabrial 2005大豆科学2005,24,4:12
11Advances in fabrication of ceramic corundum abrasives based on sol–gel process显示文摘Corundum abrasives with good chemical stability can be fabricated into various free abrasives and bonded abrasive tools that are widely used in the precision machining of various parts.However,these abrasives cannot satisfy the machining requirements of difficult-to-machine materials with high hardness,high strength,and strong wearing resistance.Although superhard abrasives can machine the above-mentioned materials,their dressing and manufacturing costs are high.By contrast,ceramic corundum abrasives fabricated by sol–gel method is a costeffective product between conventional and superhard abrasives.Ceramic corundum abrasives exhibit self-sharpening and high toughness.In this review,the optimization methods of ceramic corundum abrasive properties are introduced from three aspects:precursor synthesis,particle shaping,and sintering.Firstly,the functional mechanism of seeds and additives on the microstructural and mechanical properties of abrasives is analyzed.Specifically,seeds can reduce the phase transition temperature and improve fracture toughness.The grain size and uniformly dense structure can be controlled by applying an appropriate amount of multicomponent additives.Then,the urgent need of engineering application and machinability of special shape ceramic corundum abrasives is reviewed,and three methods of abrasive shaping are summarized.The micromold replication technique is highly advanced and can be used to prepare functional abrasives.Additionally,the influence of a new sintering method,namely,two-step sintering technique,on the microstructural and mechanical performance of ceramic corundum abrasives is summarized.Finally,the challenge and developmental trend of the optimization of ceramic corundum abrasives are prospected.Baoteng HUANG Changhe LI Yanbin ZHANG Wenfeng DING Min YANG Yuying YANG Han ZHAI Xuefeng XU Dazhong WANG Sujan DEBNATH Muhammad JAMIL Hao Nan Li Hafiz Muhammad ALI Munish Kumar GUPTA Zafar SAID 2021Chinese Journal of Aeronautics2021,34,6:11
12利用瞬变电磁和多频电磁方法监测地下水位及其对Hawara遗址的影响(英文)显示文摘利用瞬变电磁(TEM)和地面电磁(GEM)方法,本文研究了埃及Hawara遗址区的地下水对遗址的影响.这个遗址包括Hawara金字塔、北区墓地、以及被称作'迷宫'的南区墓葬场所.现今Hawara遗址已经完全荒废,被耕作区和Bahr Wahba运河包围.地表水和地下水会破坏Hawara金字塔和'迷宫'遗址的地基,现在金字塔入口已被淹没至地面下约6 m深处.本文在耕作区、金字塔以及'迷宫'等三个地区进行了TEM勘察;在'迷宫'地区进行了GEM勘察.综合分析以上两种勘察数据,我们发现,农业灌溉是浸入到地下的水的主要来源;本地区地下水位随着观测点及海拔的不同,在地面以下2~7 m之间变化.Usama MASSOUD A.M.ABBAS H.S.A.MESBAH El Said A.RAGAB Λyman TAHA 2010地球物理学报2010,53,3:10
13Post-endoscopic retrograde cholangiopancreatography pancreatitis: Risk factors and predictors of severity显示文摘AIM To detect risk factors for post-endoscopic retrograde cholangiopancreatography(ERCP) pancreatitis(PEP) and investigate the predictors of its severity.METHODS This is a prospective cohort study of all patients who underwent ERCP.Pre-ERCP data,intraoperative data,and post-ERCP data were collected.RESULTS The study population consisted of 996 patients.Their mean age at presentation was 58.42(± 14.72) years,and there were 454 male and 442 female patients.Overall,PEP occurred in 102(10.2%) patients of the study population; eighty(78.4%) cases were of mild to moderate degree,while severe pancreatitis occurred in 22(21.6%) patients.No hospital mortality was reported for any of PEP patients during the study duration.Age less than 35 years(P = 0.001,OR = 0.035),narrower common bile duct(CBD) diameter(P = 0.0001) and increased number of pancreatic cannulations(P = 0.0001) were independent risk factors for the occurrence of PEP.CONCLUSION PEP is the most frequent and devastating complication after ERCP.Age less than 35 years,narrower median CBD diameter and increased number of pancreaticcannulations are independent risk factors for the occurrence of PEP.Patients with these risk factors are candidates for prophylactic and preventive measures against PEP.Ayman El Nakeeb Ehab El Hanafy Tarek Salah Ehab Atef Hosam Hamed Ahmad M Sultan Emad Hamdy Mohamed Said Ahmed A El Geidie Tharwat Kandil Mohamed El Shobari Gamal El Ebidy 2016World Journal of Gastrointestinal Endoscopy2016,8,19:10
14Gallbladder emptying in patients with primary sclerosing cholangitis显示文摘AIM:To assess gallbladder emptying and its association with cholecystitis and abdominal pain in patients with primary sclerosing cholangitis(PSC).METHODS:Twenty patients with PSC and ten healthy subjects were investigated.Gallbladder fasting volume, ejection fraction and residual volume after ingestion of a test meal were compared in patients with PSC and healthy controls using magnetic resonance imaging.Symptoms, thickness and contrast enhancement of the gallbladder wall and the presence of cystic duct strictures were also assessed.RESULTS:Median fasting gallbladder volume in patients with PSC [67(19-348) mL] was twice that in healthy controls [32(16-55) mL](P < 0.05).The median postprandial gallbladder volume in patients with PSC was signiflcantly larger than that in healthy controls(P < 0.05).There was no difference in ejection fraction, gallbladder emptying volume or mean thickness of the gallbladder wall between PSC patients and controls.Contrast enhancement of the gallbladder wall in PSC patients was higher than that in controls;(69% ± 32%) and(42% ± 21%)(P < 0.05).No significant association was found between the gallbladder volumes and occurrence of abdominal pain in patients and controls.CONCLUSION:Patients with PSC have increased fasting gallbladder volume.Gallbladder Mucosal dysfunction secondary to chronic cholecystitis, may be a possible mechanism for increased gallbladder.Karouk Said Nick Edsborg Nils Albiin Annika Bergquist 2009World Journal of Gastroenterology2009,15,28:9
15二分之五次方抛物线形明渠设计及提高水力特性效果显示文摘为提高抛物线形断面的水力特性,增加输水能力,该文提出了一种二分之五次(以下简称2.5次)方抛物线形渠道断面,推导其水力断面特性。将湿周用高斯超几何函数表示后,将水力最优断面的最优化模型转换为关于宽深比的一元方程,得到2.5次方抛物线形渠道水力最优断面的解析解,其最优宽深比为2.088 3。比较结果表明,2.5次方抛物线形断面较常规抛物线形断面具有更好的水力学特性。与平方、半立方抛物线形断面比较,在相同水深条件下,2.5次方抛物线形水力最优断面的过流能力更大。相反,在相同流量下,2.5次方抛物线形水力最优断面的过流面积、湿周、水深更小。2.5次方抛物线形水力最优断面的建造成本与其他2种断面相比是最小的。进一步地,为便于工程应用,基于高斯勒让德算法,提出2.5次方抛物线形断面的三点和四点格式近似湿周算法。结果表明,四点格式近似算法具有较高精度。研究可为明渠设计提供理论依据。韩延成 徐征和 高学平 Said M.Easa 2017农业工程学报2017,33,4:9
16基于遗传算法和粒子群优化的模糊PID控制器在双星感应电机直接转矩控制中的应用(英文)显示文摘本文对双星感应电动机直接转矩控制的三种混合方法进行了分析、控制和比较,目的是将PID-PSO、模糊 PSO 和 GA-PSO 三种不同的启发式优化技术相结合,以改善 DSIM 速度控制回路的性能。将遗传算法和粒子群优化算法应用于 MATLAB,得到模糊粒子群算法是最合适的方案。模糊粒子群算法的主要性能是减小了大扭矩波动,加快了上升时间,避免了影响驱动性能的干扰。BOUKHALFA Ghoulemallah BELKACEM Sebti CHIKHI Abdesselem BENAGGOUNE Said 2019Journal of Central South University2019,26,7:9
17Influence of growth time on crystalline structure,conductivity and optical properties of ZnO thin films显示文摘This paper examines the growth of ZnO thin films on glass substrate at 350℃using an ultrasonic spray technique.We have investigated the influence of growth time ranging from 1 to 4 min on structural,optical and electrical properties of ZnO thin films.The as-grown films exhibit a hexagonal structure wurtzite and are(002) oriented.The maximum value of grain size G = 63.99 nm is attained for ZnO films grown at 2 min.The average transmittance is about 80%,thus the films are transparent in the visible region.The optical gap energy is found to increase from 3.26 to 3.37 eV with growth time increased from 1 to 2 min.The minimum value of electrical resistivity of the films is 0.13Ω·cm obtained at 2 min.A systematic study on the influence of growth time on the properties of ZnO thin films deposited by ultrasonic spray at 350℃has been reported.Said Benramache Foued Chabane Boubaker Benhaoua Fatima Z.Lemmadi 2013Journal of Semiconductors2013,34,2:9
18Plasmonics for solid-state lighting: enhanced excitation and directional emission of highly efficient light sources显示文摘Light sources based on reliable and energy-efficient light-emitting diodes (LEDs) are instrumental in the development of solid-statelighting (SSL). Most research efforts in SSL have focused on improving both the intrinsic quantum efficiency (QE) and the stability oflight emitters. For this reason, it is broadly accepted that with the advent of highly efficient (QE close to 1) and stable emitters, thefundamental research phase of SSL is coming to an end. In this study, we demonstrate a very large improvement in SSL emission (above70-fold directional enhancement for p-polarized emission and 60-fold enhancement for unpolarized emission) using nanophotonicstructures. This is attained by coupling emitters with very high QE to collective plasmonic resonances in periodic arrays of aluminumnanoantennas. Our results open a new path for fundamental and applied research in SSL in which plasmonic nanostructures are able tomold the spectral and angular distribution of the emission with unprecedented precision.Gabriel Lozano Davy J Louwers Said RK Rodrı´guez Shunsuke Murai Olaf TA Jansen Marc A Verschuuren Jaime Gomez Rivas 2013Light(Science & Applications)2013,2,1:8
19Cryogenic minimum quantity lubrication machining: from mechanism to application显示文摘Cutting fluid plays a cooling-lubrication role in the cutting of metal materials.However,the substantial usage of cutting fluid in traditional flood machining seriously pollutes the environment and threatens the health of workers.Environmental machining technologies,such as dry cutting,minimum quantity lubrication(MQL),and cryogenic cooling technology,have been used as substitute for flood machining.However,the insufficient cooling capacity of MQL with normal-temperature compressed gas and the lack of lubricating performance of cryogenic cooling technology limit their industrial application.The technical bottleneck of mechanical-thermal damage of difficult-to-cut materials in aerospace and other fields can be solved by combining cryogenic medium and MQL.The latest progress of cryogenic minimum quantity lubrication(CMQL)technology is reviewed in this paper,and the key scientific issues in the research achievements of CMQL are clarified.First,the application forms and process characteristics of CMQL devices in turning,milling,and grinding are systematically summarized from traditional settings to innovative design.Second,the cooling-lubrication mechanism of CMQL and its influence mechanism on material hardness,cutting force,tool wear,and workpiece surface quality in cutting are extensively revealed.The effects of CMQL are systematically analyzed based on its mechanism and application form.Results show that the application effect of CMQL is better than that of cryogenic technology or MQL alone.Finally,the prospect,which provides basis and support for engineering application and development of CMQL technology,is introduced considering the limitations of CMQL.Mingzheng LIU Changhe LI Yanbin ZHANG Qinglong AN Min YANG Teng GAO Cong MAO Bo LIU Huajun CAO Xuefeng XU Zafar SAID Sujan DEBNATH Muhammad JAMIL Hafz Muhammad ALI Shubham SHARMA 2021Frontiers of Mechanical Engineering2021,16,4:8
2046 XX karyotype during male fertility evaluation; case series and literature review显示文摘性开发的 46 XX 混乱是在人富饶的评估期间在时间观察的一个不平常的医药条件。下列是一个案例系列和与这 karyotype 诊断的 phenotypically 正常的人的文学评论。我们的目标是理解病人临床的表示以及他们的实验室结果试图探索为他们的管理可得到的选择。通过 PubMed 和 MEDLINE 数据库的正式文学评论作为词搜索用“ 46 XX 人”被执行。55 个病人的一个总数,包括在这篇文章传送的那些在他们的富饶评估期间与 46 XX karyotype 被诊断。病人平均数年龄獵摥愠 ?? 畱污瑩瑡癩? 湩楤慣潴 ? 景栠慥祶 ? 慤汩 ? 牯渠慥? 慤汩 ? 挠湡慮楢? 潣獮浵瑰潩 ? 楷桴湩琠敨瀠獡 ? 洳湯桴?Ahmad Majzoub Mohamed Arafa Christopher Starks Haitham Elbardisi Sami A1 Said Edmund Sabanegh Jr 2017Asian Journal of Andrology2017,19,2:8
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