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| 1 | Influence of bimodal grain size distribution on the corrosion behavior of friction stir processed biodegradable AZ31 magnesium alloy显示文摘In the present study,AZ31 magnesium alloy sheets were processed by friction stir processing(FSP)to investigate the effect of the grain refinement and grain size distribution on the corrosion behavior.Grain refinement from a starting size of 16.4±6.8µm to 3.2±1.2µm was attained after FSP.Remarkably,bimodal grain size distribution was observed in the nugget zone with a combination of coarse(11.62±8.4µm)and fine grains(3.2±1.2µm).Due to the grain refinement,a slight improvement in the hardness was found in the nugget zone of FSPed AZ31.The bimodal grain size distribution in the stir zone showed pronounced influence on the corrosion rate of FSPed AZ31 as observed from the immersion and electrochemical tests.From the X-ray diffraction analysis,more amount of Mg(OH)_(2) was observed on FSPed AZ31 compared with the unprocessed AZ31.Polarization measurements demonstrated the higher corrosion current density for FSPed AZ31(8.92×10^(−5)A/cm^(2))compared with the unprocessed condition(2.90×10^(−5)A/cm^(2))that can be attributed to the texture effect and large variations in the grain size which led to non-uniform galvanic intensities. | N.Saikrishna G.Pradeep Kumar Reddy Balakrishnan Munirathinam B.Ratna Sunil | 2016 | Journal of Magnesium and Alloys2016，4，1： | 13 |
| 2 | Magnesium based surface metal matrix composites by friction stir processing显示文摘Surface metal matrix composites(MMCs)are a group of modern engineered materials where the surface of the material is modified by dispersing secondary phase in the form of particles or fibers and the core of the material experience no change in chemical composition and structure.The potential applications of the surface MMCs can be found in automotive,aerospace,biomedical and power industries.Recently,friction stir processing(FSP)technique has been gaining wide popularity in producing surface composites in solid state itself.Magnesium and its alloys being difficult to process metals also have been successfully processed by FSP to fabricate surface MMCs.The aim of the present paper is to provide a comprehensive summary of state-of-the-art in fabricating magnesium based composites by FSP.Influence of the secondary phase particles and grain refinement resulted from FSP on the properties of these composites is also discussed. | B.Ratna Sunil G.Pradeep Kumar Reddy Hemendra Patle Ravikumar Dumpala | 2016 | Journal of Magnesium and Alloys2016，4，1： | 6 |
| 3 | Effect of aluminum content on machining characteristics of AZ31 and AZ91 magnesium alloys during drilling显示文摘Magnesium(Mg)and its alloys are now becoming the promising choice for various structural applications due to their low density and high specific strength compared with other light metals such as aluminum and its alloys.Among all Mg alloys,AZ(aluminum and zinc)series is the most widely used alloy system for various structural applications.But,machining of magnesium and its alloys involves certain issues due to their brittle nature and risk of inflammability unlike other nonferrous metals.Particularly,alloys with considerable amount of secondary phase may exhibit different machining characteristics during metal cutting operations.In the present study,two AZ series alloys AZ31 and AZ91 were selected and drilling operation was performed to assess the effect of the secondary phase amount and distribution on machining characteristics.Drilling operation was carried out at different sets of process parameters and cutting forces were obtained and the chips which have been produced during drilling were analyzed.From the results,it can be clearly understood that the presence of secondary phase(Mg_(17)Al_(12))has a significant influence on cutting forces.Increase in cutting speed has reduced the required cutting force and load fluctuations in all the cases. | B.Ratna Sunil K.V.Ganesh P.Pavan G.Vadapalli Ch Swarnalatha P.Swapna P.Bindukumar G.Pradeep Kumar Reddy | 2016 | Journal of Magnesium and Alloys2016，4，1： | 4 |
| 4 | An investigation on the hardness and corrosion behavior of MWCNT/Mg composites and grain refined Mg显示文摘In the present work,multi walled carbon nanotubes(MWCNT)reinforced magnesium(Mg)matrix composite was fabricated by friction stir processing(FSP)with an aim to explore its mechanical and electrochemical behavior.Microstructural observations showed that the thickness of the produced composite layer was in the range of 2500μm.FSP resulted uniform distribution of CNT near the surface while agglomerated layers in the subsurface.Grain refinement of Mg achieved by FSP improved the hardness but significant enhancement in the hardness value was observed for FSPed MWCNT/Mg composites.Potentiodynamic polarization studies revealed that the increase in corrosion current density was observed for MWCNT/Mg composite compared with grain refined Mg and pure Mg,implying the significance of secondary phase(MWCNT)in decreasing the corrosion resistance of the composite. | N.Saikrishna G.Pradeep Kumar Reddy Balakrishnan Munirathinam Ravikumar Dumpala M.Jagannatham B.Ratna Sunil | 2018 | Journal of Magnesium and Alloys2018，6，1： | 4 |
| 5 | Laparoscopic vs open partial colectomy in elderly patients:Insights from the American College of Surgeons- National Surgical Quality Improvement Program database显示文摘AIM: To compare the outcomes between the laparoscopic and open approaches for partial colectomy in elderly patients aged 65 years and over using the American College of Surgeons- National Surgical Quality Improvement Program(ACS NSQIP) database. METHODS: The ACS NSQIP database for the years 2005-2011 was queried for all patients 65 years and above who underwent partial colectomy. 1:1 propensity score matching using the nearest- neighbor method was performed to ensure both groups had similar preoperative comorbidities. Outcomes including postoperative complications, length of stay and mortality were compared between the laparoscopic and open groups. χ2 and Fisher's exact test were used for discrete variables and Student's t-test for continuous variables. P < 0.05 was considered significant and odds ratios with 95%CI were reported when applicable. RESULTS: The total number of patients in the ACS NSQIP database of the years 2005-2011 was 1777035. We identified 27604 elderly patients who underwent partial colectomy with complete data sets. 12009(43%) of the cases were done laparoscopically and15595(57%) were done with open. After propensity score matching, there were 11008 patients each in the laparoscopic(LC) and open colectomy(OC) cohorts. The laparoscopic approach had lower post-operative complications(LC 15.2%, OC 23.8%, P < 0.001), shorter length of stay(LC 6.61 d, OC 9.62 d, P < 0.001) and lower mortality(LC 1.6%, OC 2.9%, P < 0.001). CONCLUSION: Even after propensity score matching, elderly patients in the ACS NSQIP database having a laparoscopic partial colectomy had better outcomes than those having open colectomies. In the absence of specific contraindications, elderly patients requiring a partial colectomy should be offered the laparoscopic approach. | Umashankkar Kannan Vemuru Sunil K Reddy Amar N Mukerji Vellore S Parithivel Ajay K Shah Brian F Gilchrist Daniel T Farkas | 2015 | World Journal of Gastroenterology2015，21，45： | 3 |
| 6 | Joining of AZ31 and AZ91 Mg alloys by friction stir welding显示文摘Two dissimilar magnesium(Mg)alloy sheets,one with low aluminium(AZ31)and another with high aluminium(AZ91)content,were successfully joined by friction stir welding(FSW).The effect of process parameters on the formation of hot cracks was investigated.A sound metallurgical joint was obtained at optimized process parameters(1400 rpm with 25 mm/min feed)which contained fine grains and distributed β(Mg_(17)Al_(12))phase within the nugget zone.An increasing trend in the hardness measurements has also confirmed more amount of dissolution of aluminium within the nugget zone.A sharp interface between nugget zone and thermo mechanical affected zone(TMAZ)was clearly noticed at the AZ31 Mg alloy side(advancing)but not on the AZ91 Mg alloy side(retreating).From the results it can be concluded that FSW can be effectively used to join dissimilar metals,particularly difficult to process metals such as Mg alloys,and hot cracking can be completely eliminated by choosing appropriate process parameters to achieve sound joint. | B.Ratna Sunil G.Pradeep Kumar Reddy A.S.N.Mounika P.Navya Sree P.Rama Pinneswari I.Ambica R.Ajay Babu P.Amarnadh | 2015 | Journal of Magnesium and Alloys2015，3，4： | 3 |
| 7 | Joining of AZ91 Mg alloy and Al6063 alloy sheets by friction stir welding显示文摘In the present work,the effect of process parameters on joining of AZ91 Mg alloy and Al6063 aluminum alloy sheets during friction stir welding(FSP)was studied.A successful joint was achieved at 1100 r.p.m.tool rotational speed and 25 mm/min tool travel speed.Combination of tool rotational speed and tool travel speed has observed a profound effect on the material flow mechanisms at the nugget zone.From the microstructural studies,the joint formation was observed as mainly due to mechanical mixing of the materials.The level of metallurgical continuity at the nugget zone was observed as poor and a sharp interface at the joint was noticed.The microhardness measurements across the weld joint also revealed the lack of establishment of a perfect metallurgical bonding.X-ray diffraction analysis of weld zone showed presence of both magnesium and aluminum.Hence from the preliminary observations,it can be understood that the joining of AZ91 Mg alloy and Al6063 alloy can be achieved by FSP;however,complex issues in material mixing still need further investigations. | B.Lakshmana Prasad G.Neelaiah M.Gopi Krishna S.V.V.Ramana K.Sai Prakash G.Sarika G.Pradeep Kumar Reddy Ravikumar Dumpala B.Ratna Sunil | 2018 | Journal of Magnesium and Alloys2018，6，1： | 2 |
| 8 | Can Hybrid SPECT-CT Overcome the Limitations Associated With Poor Imaging Properties of 131I-MIBG?: Comparison With Planar Scintigraphy and SPECT in Pheochromocytoma显示文摘 | Punit Sharma Varun Singh Dhull Sunil Jeph Rama Mohan Reddy Harmandeep Singh Niraj Naswa Chandrasekhar Bal Rakesh Kumar | 2013 | Clinical Nuclear Medicine2013，，： | 1 |
| 9 | Surgical removal of a left ventricular myxoma in an infant显示文摘 | Reddy SN Sunil G Kumar RK | 2013 | Ann Pediatr Cardiol2013，6，2： | 1 |
| 10 | Impact of medial open-wedge high tibial osteotomy for medial compartment osteoarthritis of the knee显示文摘BACKGROUND Most populations worldwide,who are used to squatting and sitting cross-legged for their activities of daily living,largely comprise the lower socioeconomic strata,thus making them candidates for exclusion for total knee arthroplasty.Proximal/high tibial osteotomy(HTO)is a preferred strategy for clinically symptomatic osteoarthritis(OA)with genu varum due to painful medial compartment OA which is not amenable to conservative measures.AIM To evaluate the outcomes of medial open-wedge HTO along with autologous bone grafting and buttress plate for the treatment of genu varum due to OA of the knee in a rural population of central India.METHODS A total of 65 knees in 56 patients with a mean age of 58.22±5.63 years with genu varum due to intractable painful knee OA were treated with medial open-wedge HTO along with autologous bone grafting and buttress plate osteosynthesis from June 2015 to May 2018.The mean preoperative radiological angle of genu varum was 13.4°.Clinical outcomes were assessed by the range of movement,knee scores,pain scores,and functional scores.Radiographic studies were performed preoperatively and at regular intervals during the follow-up period.RESULTS All patients reported pain relief immediately after the osteotomy and during the long-term analysis covering between one to three years.The genu varum angle was overcorrected to approximately four degrees in all patients.There was a loss of reduction by approximately three degrees in all patients at around six weeks postoperatively.Preoperative knee movements were restored in all patients.No major perioperative complications were noted during surgery and postoperative follow-up and the clinical scores were significantly improved during the final analysis which revealed good pain relief.CONCLUSION Medial open-wedge HTO is a reliable,safe,practical,physiological,and feasible treatment for populations who are used to increased activity in their occupation and lifestyle and is associated with excellent short-term and long-term results for OA in genu varum knees. | Sunil Sheshrao Nikose Devashree Nikose Aditya L Kekatpure Shashank Jain Kiran Saoji Sridhar M Reddy | 2020 | World Journal of Orthopedics2020，11，12： | 1 |
| 11 | Methods for making alloy 600 resistant to sensitization and intergranular corrosion显示文摘 | Sunil Kumar B. Balla Sai Prasad Vivekanand Kain Jayanth Reddy | 2013 | Corrosion Science2013，，： | 1 |
| 12 | Regional odontodysplasia显示文摘 | Thimma Reddy BV Vinay Reddy KK Sunil B | 2010 | J Indian Soc Pedod Prey Dent2010，28，4： | 1 |
| 13 | Design,synthesis and screening of some novel benzoxazole based 1,3,4-oxadiazoles as potential antimicrobial agents显示文摘一系列新奇的2-(5-substituted-[ 1,3,4 ] oxadiazol-2-yl ) -benzoxazoles ( 7ah )被作为原料和 benzoxazole-2-carbonyl 氯化物( 2 )包含 benzoxazole-2-carboxylic 酸( 1 )在二个不同方向在好收益综合, benzoxazole-2-carboxylic 酸甲基酉旨( 3 ), benzoxazole-2-carboxylic 酸一种肺结核特效药( 4 ), benzoxazole-2-carboxylic 酸N乙酰一种肺结核特效药( 5ad )和象反应中介的 benzoxazole-2-carboxylic acid-ethylidene-hydrazides ( 6ad )。所有综合混合物的化学结构被他们的红外, 1H NMR 和 13C NMR 和团阐明光谱数据。进一步,目标混合物对各种各样的克积极、克否定的细菌为他们的抗菌剂活动被屏蔽。 | Sunil Vodela Raghu Vardhan Reddy Mekala Ravinder Reddy Danda Venkateshwarlu Kodhati | 2013 | Chinese Chemical Letters2013，24，7： | 0 |
| 14 | 膝关节置换术松止血带时机随机对照研究的荟萃分析显示文摘背景:膝关节置换术中某些外科医生在关闭切口前松止血带以达到止血的目的。我们通过对随机对照研究的荟萃分析法观察关闭切口前松止血带是否会减少围手术期失血,及关闭切口后再松止血带是否会增加术后早期并发症的风险。方法:检索电子数据库及相关文献的参考目录,搜集到所有已发表的用于论证这些问题的随机对照试验,进行荟萃分析。结果:对涉及872例893膝初次膝关节置换患者的11项研究进行系统分析。这些研究具有显著的临床和方法学上的多样性。早松止血带增加了总出血量(加权均数差=228.7ml;95%可信区间为168.3-289.1;p〈0.00001)。通过血红蛋白浓度最大丢失量的计算也提示早松止血带增加失血量(加权均数差=320.7ml;95%可信区间为204.3-4.37.1;p〈0.00001)。术后并发症须再手术率在迟松止血带组为3.1%(9/290),而在早松止血带组则为0.3%(1/290);两者风险差距为3%(95%可信区间为0.1-5%),差异有统计学意义(p=0.04)。结论:关闭切口前松止血带增加了初次膝关节置换术中的失血量,而关闭切口后松止血带增加了致再次手术的早期并发症的发生风险,为进一步揭示膝关节置换术后发生与迟松止血带相关早期并发症的风险仍须进行大量的优质研究。 | Krishna Reddi Boddu Siva Rama Sunil Apsingi Sharmila Poovali Anand Jetti 陈光兴(译) 古凌川(译) | 2008 | 中华骨科杂志2008，28，3： | 0 |
| 15 | Oncologic outcomes with and without amniotic membranes in robotic-assisted radical prostatectomy:A propensity score matched analysis显示文摘Objective:Placement of human placenta derived grafts during robotic-assisted radical prostatectomy(RARP)hastens the return of continence and potency.The long-term impact on the oncologic outcomes remains to be investigated.Our objective was to determine the oncologic outcomes of patients with dehydrated human amnion chorion membrane(dHACM)at RARP compared to a matched cohort.Methods:In a referral centre,from August 2013 to October 2019,599 patients used dHACM in bilateral nerve-sparing RARP.We excluded patients with less than 12 months follow-up,simple prostatectomy,and unilateral nerve-sparing.Patients with dHACM(amnio group)were 529,and were propensity score matched 1:1 to 2465 patients without dHACM(non-amnio group)and a minimum follow-up of 36 months.At the time of RARP,dHACM was placed around the neurovascular bundle in the amnio group.Continuous and categorical variables in matched groups was tested by two-sample Kolmogorov-Smirnov test and Fisher's exact test respectively.Outcomes measured were biochemical recurrence(BCR),adjuvant and salvage therapy rates.Results:Propensity score matching resulted in two groups of 444 patients.Cumulative incidence functions for BCR did not show a difference between the groups(p=0.3).Patients in the non-amnio group required salvage therapy more frequently than the amnio group,particularly after partial nerve-sparing RARP(6.3%vs.2.3%,p=0.001).Limitations are the absence of prospective randomization.Conclusion:The data suggest that using dHACM does not have a negative impact on BCR in patients.Outcomes of cancer specific and overall survival will require follow-up study to increase our understanding of these grafts’impact on prostate cancer biology. | Jonathan Noël Daniel Stirt Marcio Covas Moschovas Sunil Reddy Abdel Rahman Jaber Marco Sandri Seetharam Bhat Travis Rogers Subuhee Ahmed Anya Mascarenhas Ela Patel Vipul Patel | 2024 | Asian Journal of Urology2024，11，1： | 0 |
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