About

Sam Kumar is an Assistant Professor of Computer Science at UCLA Samueli School of Engineering. His research interests include security systems and networked systems. Kumar completed his PhD in Computer Science at UC Berkeley in 2023. His notable contributions include work on optimizing transfer costs and throughput using cloud-aware overlays, nearly zero-cost virtual memory for secure computation, performant TCP for low-power wireless networks, and secure data-sharing systems from decentralized trust. His research has been recognized with awards such as the Jay Lepreau Best Paper Award at OSDI 2021 and an Applied Networking Research Prize from the IETF/IRTF in 2022. Kumar's work focuses on advancing secure, efficient, and scalable networked systems and security frameworks.

Research topics

• Medicine
• Internal medicine
• Computer Science
• Family medicine
• Psychology
• Anesthesia
• Radiology
• Virology
• Intensive care medicine
• Biology
• Immunology
• Multimedia
• Pathology
• Pedagogy
• Medical education

Selected publications

• Neuronal infection is a major pathogenetic mechanism and cause of fatalities in human acute Nipah virus encephalitis

  Neuropathology and Applied Neurobiology · 2022 · 10 citations

  • Pathology
  • Biology
  • Medicine

  OBJECTIVES: Acute Nipah (NiV) encephalitis is characterised by a dual pathogenetic mechanism of neuroglial infection and ischaemia-microinfarction associated with vasculitis-induced thrombotic occlusion. We investigated the contributions of these two mechanisms in fatal cases. MATERIALS AND METHODS: We analysed brain tissues (cerebrum, brainstem and cerebellum) from 15 autopsies using light microscopy, immunohistochemistry (IHC), in situ hybridisation and quantitative methods. RESULTS: Three types of discrete plaque-like parenchymal lesions were identified: Type 1 with neuroglial IHC positivity for viral antigens and minimal or no necrosis; Type 2 with neuroglial immunopositivity and necrosis; and Type 3 with necrosis but no viral antigens. Most viral antigen/RNA-positive cells were neurons. Cerebral glial immunopositivity was rare, suggesting that microinfarction played a more important role in white matter injury. Type 1 lesions were also detected in the brainstem and cerebellum, but the differences between cerebral cortex and these two regions were not statistically significant. In the cerebral cortex, Type 1 lesions overwhelmingly predominated, and only 14% Type 1 vs 69% Type 2 lesions were associated with thrombosis. This suggests that neuronal infection as a mechanism of pathogenesis was more important than microinfarction, both in general and in Type 1 lesions in particular. Between the 'early' group (<8-day fever) and the 'late' group (≥8-day fever), there was a decrease of Type 1 and Type 2 lesions with a concomitant increase of Type 3 lesions, suggesting the latter possibly represented late-stage microinfarction and/or neuronal infection. CONCLUSION: Neuronal infection appears to play a more important role than vasculopathy-induced microinfarction in acute NiV encephalitis.

  DOI

• Early clinical exposure as perceived by Ist year MBBS students during online sessions - A necessity in Covid era

  Journal of Education Technology in Health Sciences · 2021 · 3 citations

  1st authorCorresponding
  • Computer Science
  • Medical education
  • Medicine

  Background: New CBME curriculum has laid emphasis on early clinical exposure (ECE) in the current year. Thirty hours are dedicated in the curriculum in first year for ECE. Due to Covid-19 pandemic that started in march 2019 the students could not be taken to hospitals for their ECE sessions and all the teaching and practical sessions were shifted to online sessions. So it was decided to give the students ECE through online classes. As it was a totally new experience for both the students and the faculty to take all classes online. A feedback was taken from first year students regarding their first experience for taking the ECE sessions online. Aim: Introduce the online session for ECE in First year MBBS during the Covid era. Materials and Methods: A prospective study was done on 90 first year MBBS students who consented for this study in Department of Anatomy, HIMSR, Delhi after getting approval from Institutional Ethical committee. The duration of study was of four months that is between September 2020 to December 2020. ECE sessions were taken for 2 topics i.e foot drop and varicose veins by online mode during the lockdown due to the pandemic. ECE modules for the topics were prepared and sessions were conducted as recommended by MCI. The learning objectives were set and total duration of each session was 3-4 hours. The Questionnaire was prepared and the feed back of these sessions was taken by google forms and statistical analysis was done. Results: Majority of the students (97%) responded that ECE module was helpful. 66% responded that videos shown in the session has helped them to learn more. 29% students were of opinion that the discussion part of the session has helped them to learn the topic better. 89.2% found the ECE module in making the topic interesting and 49.2% students were of opinion that online sessions should be conducted along with classroom settings. Conclusion: The students recognized the importance of online ECE sessions during pandemic. They fou

  DOI

• Development of low-cost portable ultrasonic nebulizer in COVID 19 Era : DIY nano nebulizer

  2021 · 1 citations

  Senior authorCorresponding
  • Medicine
  • Intensive care medicine
  • Virology

  Abstract:Respiratory diseases are major public health problem in resource poor countries. This global problem greatly accentuated in the COVID 19 pandemic, which results in shortage of resources. Nebulized therapy is the recommended therapy for the patients with respiratory diseases with or without COVID 19. Jet nebulizers are bulky and ultrasonic are expensive. Therefore we are describing novel, simple, inexpensive, DIY – Nano nebulizer which can be use a homemade solution without the need of specific equipment.

  DOI

Frequent coauthors

• Jean de Vellis

  26 shared

• Ranjana Verma

  Institute of Medical Sciences

  10 shared

• Juan Carlos Biancotti

  Johns Hopkins University

  8 shared

• Tarmizi Thayaparan

  7 shared

• Raj D. Mehra

  All India Institute of Medical Sciences

  6 shared

• Arpita Mahajan

  Chandigarh University

  6 shared

• Priyanka Rana

  Post Graduate Institute of Medical Education and Research

  6 shared

• Sree Raman

  California State University, Long Beach

  6 shared

Awards & honors

• Jay Lepreau Best Paper Award at OSDI 2021
• Applied Networking Research Prize from the IETF/IRTF in 2022
• Best Paper Runner-Up Award at SenSys 2018

Similar researchers at University of California, Los Angeles

• Antoni Ribash-218
• Timothy Cloughesyh-173
• Owen Witteh-170
• Yu Huangh-166
• David S. Eisenbergh-159