Pre-route EM Verification for Modern IC Layout Using Greedy Methodology

Srinath Balasubramanian,Balreddy Rajitha 대한전자공학회 2020 Journal of semiconductor technology and science Vol.20 No.4

Electromigration (EM) is one of the important parameters to consider in the reliability of ICs. However, only few physical design flows exist to EM avoidance in the pre-CTS stage, and hence early EM avoidance framework is presented to identify the affected interconnects by EM using commercial tools. In this paper, a refinement methodology is developed and presented to reduce the EM violations in the MSV design layout and it is demonstrated that proposed framework helps in reducing EM violations along with optimization of performance. The proposed methodology is integrated inside an existing EDA tool and implemented in IWLS benchmark circuit consisting three voltage islands. Experimental results show that the proposed methodology reduces the EM violation in the multiple supply voltages layout while preserving the routing configurations in early stages of physical design process.

Sol–gel synthesis of soda lime silica-based bioceramics using biomass as renewable sources

Palakurthy Srinath,Azeem P. Abdul,Reddy K. Venugopal 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.1

The purpose of the work is to prepare and assess soda lime silica-based (SiO 2 – CaO – Na 2 O) bioactive ceramics using biomass as renewable sources. Thus we produced SiO 2 – CaO – Na 2 O-based bioactive ceramics by sol–gel process using rice husk and eggshells as sources of silica and calcium oxide, respectively. The precursors such as calcinated eggshell powder, rice husk ash (RHA) and sodium hydroxide (NaOH) were processed by sol–gel method, resultant in SiO 2 – CaO – Na 2 O-based bioactive ceramics. The gel-derived sintered sample showed combeite high (Na 6 Ca 3 Si 6 O 18 ) as a major crystalline phase. Subsequently, the sintered specimens were analyzed from the physical and structural point of view, and in terms of apatite mineralization rate in simulated environments and cytocompatibility in relative to human osteoblast-like cells. The studies showed that the produced crystalline SiO 2 – CaO – Na 2 O-based ceramics showed an average porosity of 45%. In vitro evaluation of the biological properties revealed that the prepared ceramics possesses the mineralization of carbonated hydroxyapatite (CHA) in simulated environment with good cytocompatibility and controlled degradation rate. Therefore, the results obtained sug- gest that the prepared SiO 2 – CaO – Na 2 O-based bioactive ceramics using biomass as renewable sources might be a low cost ceramics for applications in biomedical field.

산화제와 Amine계열의 가교제로 Cross-linking된 PI 분리막의 내산성 연구

강우석,Srinath Ravi,권영남 한국막학회 2021 한국막학회 총회 및 학술발표회 Vol.2021 No.04

Isolation and Characterization of Novel Lipase Gene LipHim1 from the DNA Isolated from Soil Samples

Pavan Kumar Pindi,Raja Srinath R.,Theetha L. Pavankumar 한국미생물학회 2014 The journal of microbiology Vol.52 No.5

Metagenomics is a magnificent tool to isolate genes fromunknown/uncharacterized species and also from organismsthat cannot be cultured. In this study, we constructed a metagenomiclibrary from isolated DNA of soil samples collectedfrom Palamuru University campus premises, in Mahabubnagardistrict of Andhra Pradesh, India. We isolated a novellipase gene LipHim1, which has an open reading frame of591 base pairs and encodes ~23 kDa protein consisting of196 amino acids. The Lipase LipHim1 showed maximum32% homology at the protein level with the extracellularAeromonas hydrophila lipase (Class II, GDSL family) and wassignificantly different from all other known lipases. Theisolated lipase catalyzed the hydrolysis of fatty acid esters ofpolyoxyethylene sorbitan such as Tween 60. Our results indicatethat the isolated lipase gene is novel.

Aerodynamic design optimization of an aircraft wing for drag reduction using computational fluid dynamics approach

Shiva Kumar M.R,Srinath R,Vigneshwar K,Ravi Kumar B. 한국풍공학회 2020 Wind and Structures, An International Journal (WAS Vol.31 No.1

The aircraft industry supports aviation by building aircraft and manufacturing aircraft parts for their maintenance. Fuel economization is one of the biggest concerns in the aircraft industry. The reduction in specific fuel consumption of aircraft can be achieved by a variety of means, simplest and more effective is the one to impose minor modifications in the aircraft main wing or the parts which are exposed to the air flow. This method can lead to a reduction in aerodynamic resistance offered by the air and have a smoother flight. The main objective of this study is to propose geometric design modifications on an existing aircraft wing which acts as a vortex generator and it can reduce the drag and increase lift to drag ratio, leading to lower fuel consumption. The NACA 2412 aircraft wing is modified and designed. Rigorous flow analysis is carried out using computational fluid dynamics based software Ansys Fluent. Results show that saw tooth modification to the main wing shows the best aerodynamic efficiency as compared to other modifications.

Development of Self-lubricating Nickel Based Composite Clad using Microwave Heating in Improving Resistance to Wear at Elevated Temperatures

G. Suresh,M. R. Ramesh,M. S. Srinath 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.8

This paper reports on a study of the high-temperature tribological performance of self-lubricating nickel-based compositeclad. A porous and crack free clad containing matrix, reinforcement, and lubricant phase is developed on titanium 31 alloyusing microwave irradiation. The microstructure of both NiCrSiB/WC and NiCrSiB/WC/Ag/BaF2 clad revealed very goodmetallurgical bonding with the substrate. The average microhardness of NiCrSiB/WC and NiCrSiB/WC/Ag/BaF2 clad is710.58 HV and 650.25 HV respectively, is comparatively higher than the titanium 31 substrate (320 HV). The addition of Agand BaF2solid lubricants in the clad endowing clad to operate at a broad temperature range. Compared with the NiCrSiB/WCclad, solid lubricant encapsulate clad has shown very low friction coefficient and wear rates. The sliding wear characteristicsof the clad were investigated by varying load and temperatures. The results revealed that oxide phases (NiO and Cr3O)andlubricant phases (Ag and BaWO4)formed at low and high temperatures are adequate to reduce delamination and material loss.

Evaluation of Local Recurrence in Giant-Cell Tumor of Bone Treated by Neoadjuvant Denosumab

Pramod Shekarappa Chinder,Suraj Hindiskere,Srinath Doddarangappa,Utkarsh Pal 대한정형외과학회 2019 Clinics in Orthopedic Surgery Vol.11 No.3

Background: Giant-cell tumor of bone (GCTB) is a locally aggressive primary benign tumor presenting as an expansile osteolytic lesion affecting the epiphysis of long bones. Denosumab halts the osteolysis by giant cells thereby downstaging the tumor, helping in performing less morbid procedures to remove the tumor. Our aim was to report the incidence of local recurrence (LR) in patients operated following neoadjuvant denosumab, to investigate factors associated with LR following extended curettage for GCTB, and to compare the postoperative functional and oncological outcome of patients operated with and without neoadjuvant denosumab. Methods: A total of 123 patients with a mean age of 29.6 years undergoing extended curettage for GCTB were retrospectively divided into group 1 receiving neoadjuvant denosumab and group 2 operated without denosumab. The mean follow-up period was 35 months. The perioperative characteristics and outcome were compared between the two groups and the factors for LR of GCTB were analyzed. Results: The incidence of LR among patients operated after neoadjuvant denosumab therapy was 42.8% and was significantly high compared to that in patients without denosumab (p < 0.001). On multivariate logistic regression analysis, use of denosumab as a neoadjuvant was the only factor independently associated with LR following surgery (p = 0.002). Patients treated with denosumab had a lower LR-free survival rate (log-rank, p = 0.018). Conclusions: Denosumab was independently associated with increased LR following surgery for GCTB. Denosumab has to be used cautiously in patients in whom the burden of downstaging the disease outweighs the possible chance of LR.

Severe Preoperative Disability Is Associated With Greater Mental Health Improvements Following Surgery for Degenerative Spondylolisthesis: A Cohort Matched Analysis

Ishan Khosla,Fatima N. Anwar,Andrea M. Roca,Srinath S. Medakkar,Alexandra C. Loya,Aayush Kaul,Jacob C. Wolf,Vincent P. Federico,Arash J. Sayari,Gregory D. Lopez,Kern Singh 대한척추신경외과학회 2024 Neurospine Vol.21 No.1

Objective: To evaluate preoperative disability’s influence on patient-reported outcomes (PROs) following surgery for degenerative spondylolisthesis (DS). Methods: DS patients who underwent surgical intervention were retrospectively identified from a single-surgeon spine registry. Cohorts based on Oswestry Disability Index (ODI) < 41 (milder disability) and ≥ 41 (severe disability) were created. Demographic differences were accounted for with 1:1 propensity score matching. For the matched sample, perioperative and PRO data were additionally collected. PROs assessed included mental health, physical function, pain, and disability. Pre- and up to 2-year postoperative PROs were utilized. Average time to final follow-up was 15.7 ± 8.8 months. Improvements in PROs and minimal clinically important difference (MCID) rates were calculated. Continuous variables were compared through Student t-test and categorical variables were compared through chi-square tests. Results: Altogether, 214 patients were included with 77 in the milder disability group. The severe disability group had worse postoperative day (POD) 1 pain scores and longer hospital stays (p ≤ 0.038, both). The severe disability group reported worse outcomes pre- and postoperatively (p < 0.011, all), but had greater average improvement in 12-item Short Form health survey mental composite score (SF-12 MCS), 9-Item Patient Health Questionnaire (PHQ-9), visual analogue scale (VAS)-back, and ODI by 6 weeks (p ≤ 0.037, all) and PHQ-9, VAS-back and ODI by final follow-up (p ≤ 0.015, all). The severe disability cohort was more likely to achieve MCID for SF-12 MCS, PHQ-9, and ODI (p ≤ 0.003, all). Conclusion: Patients with greater baseline disability report higher POD 1 pain and discharge later than patients with milder disability. While these patients report inferior physical/mental health before and after surgery, they report greater improvements in mental health and disability postoperatively.

Determinants of Tobacco Cessation Behaviour among Smokers and Smokeless Tobacco Users in the States of Gujarat and Andhra Pradesh, India

Sarkar, Bidyut K.,Arora, Monika,Gupta, Vinay K.,Reddy, K. Srinath Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.3

Background: This study was undertaken to identify the socio-demographic determinants of quit attempts among smokers and smokeless tobacco users to identify correlates of tobacco cessation behaviour in India Materials and Methods: This was a cross-sectional study for the outcome of quit attempts made by current tobacco users in last 12 months in twelve districts in two states. Simple and multivariable logistic regression analysis was used to obtain the odds ratios (ORs) of socio-demographic variables (age, gender, education, occupation, socio-economic status, community, area, type of family) and tobacco user status (smoker/smokeless). Results: In the combined analysis, a smoker had higher predicted probability of attempting quitting (OR-1.41,CI 1.14-1.90), in comparison to a smokeless tobacco user and a tobacco user in the state of Gujarat was less likely to attempt quitting than a user in Andhra Pradesh (OR-0.60, CI 0.47-0.78). The probability of making a quit attempt was higher among tobacco users who were more educated (OR-1.40, CI 1.04-1.94), having a higher socio-economic status (SES) (OR-2.39, CI 1.54-3.69), and belonging to non-agricultural labourer occupational group (OR-1.90, CI 1.29-2.78). The effects were maintained even after adjusting for all other variables. In disaggregated analysis, findings were similar except in smokeless as a separate group, education level was not significantly associated with quit attempts and with lower odds (OR-0.91, CI 0.58-1.42). Conclusions: This is one of the first studies to provide useful insight into potential determinants for quit attempts of tobacco users in India including smokeless tobacco users, exploring the socio-demographic patterning of correlates of quit attempts.

Prognostic Value in Preoperative Veterans RAND-12 Mental Component Score on Clinical Outcomes for Patients Undergoing Minimally Invasive Lateral Lumbar Interbody Fusion

Ishan Khosla,Fatima N. Anwar,Andrea M. Roca,Srinath S. Medakkar,Alexandra C. Loya,Keith R. MacGregor,Omolabake O. Oyetayo,Eileen Zheng,Aayush Kaul,Jacob C. Wolf,Vincent P. Federico,Gregory D. Lopez,Ar 대한척추신경외과학회 2024 Neurospine Vol.21 No.1

Objective: To evaluate the effect of Veterans RAND 12-item health survey mental composite score (VR-12 MCS) on postoperative patient-reported outcome measures (PROMs) after undergoing lateral lumbar interbody fusion. Methods: Retrospective data from a single-surgeon database created 2 cohorts: patients with VR-12 MCS ≥ 50 or VR-12 MCS < 50. Preoperative, 6-week, and final follow-up (FF)- PROMs including VR-12 MCS/physical composite score (PCS), 12-item Short Form health survey (SF-12) MCS/PCS, Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF), Patient Health Questionnaire-9 (PHQ-9), visual analogue scale (VAS)-back/leg pain (VAS-BP/LP), and Oswestry Disability Index (ODI) were collected. ∆6-week and ∆FF-PROMs were calculated. Minimal clinically important difference (MCID) achievement rates were determined from established cutoffs from the literature. For intercohort comparison, chi-square analysis was used for categorical variables, and Student t-test for continuous variables. Results: Seventy-nine patients were included; 25 were in VR-12 MCS < 50. Mean postoperative follow-up time was 17.12 ± 8.43 months. The VR-12 MCS < 50 cohort had worse VR-12 PCS, SF-12 MCS, PROMIS-PF, PHQ-9, VAS-BP, and ODI scores preoperatively (p ≤ 0.014, all), worse VR-12 MCS/PCS, SF-12 MCS, PROMIS-PF, PHQ-9, and ODI scores at 6-week postoperatively (p ≤ 0.039, all), and worse VR-12 MCS, SF-12 MCS, PROMIS-PF, PHQ-9, VAS-BP, VAS-LP, and ODI scores at FF (p ≤ 0.046, all). The VR-12 MCS < 50 cohort showed greater improvement in VR-12 MCS and SF-12 MCS scores at 6 weeks and FF (p ≤ 0.005, all). The VR-12 MCS < 50 cohort experienced greater MCID achievement for VR-12 MCS, SF-12 MCS, and PHQ-9 (p ≤ 0.006, all). Conclusion: VR-12 MCS < 50 yielded worse mental health, physical function, pain and disability postoperatively, yet reported greater improvements in magnitude and MCID achievement for mental health.