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Ajay Kumar Pandey

Bio: Ajay Kumar Pandey is an academic researcher from Maulana Azad National Institute of Technology. The author has contributed to research in topics: Finite element method & Aerodynamic heating. The author has an hindex of 10, co-authored 47 publications receiving 253 citations. Previous affiliations of Ajay Kumar Pandey include Homi Bhabha National Institute & Indian Institute of Information Technology, Design and Manufacturing, Jabalpur.

Papers
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Journal ArticleDOI
TL;DR: This review mainly focuses on bone - biodegradable implant interface with due consideration accorded to the mechanical properties, degradation rates and healing process in a standard duration.

96 citations

Journal ArticleDOI
TL;DR: A case of PRES is described in an elderly bone marrow transplant recipient who presented with focal neurological deficits concerning for a cerebrovascular accident and CTP played a pivotal role in the diagnosis and initiation of appropriate management.
Abstract: Posterior reversible encephalopathy syndrome (PRES) can present with focal neurologic deficits, mimicking a stroke and can often represent a diagnostic challenge when presenting atypically. A high degree of suspicion is required in the clinical setting in order to yield the diagnosis. Cerebral CT perfusion (CTP) is utilized in many institutions as the first line in acute stroke imaging. CTP has proved to be a very sensitive measure of cerebral blood flow dynamics, most commonly employed to delineate the infarcted tissue from penumbra (at-risk tissue) in ischemic strokes. But abnormal CTP is also seen in stroke mimics such as seizures, hypoglycemia, tumors, migraines and PRES. In this article we describe a case of PRES in an elderly bone marrow transplant recipient who presented with focal neurological deficits concerning for a cerebrovascular accident. CTP played a pivotal role in the diagnosis and initiation of appropriate management. We also briefly discuss the pathophysiology of PRES.

53 citations

Journal ArticleDOI
TL;DR: A method for the comparative analysis of a metabolic pathway to study its evolution based on similarity between enzymatic reactions is introduced.
Abstract: Melanogenesis is a complex multistep process of high molecular weight melanins production by hydroxylation and polymerization of polyphenols. Melanins have a wide range of applications other than being a sun - protection pigment. Melanogenesis pathway exists from prokaryotes to eukaryotes. It has evolved over years owing to the fact that the melanin pigment has different roles in diverse taxa of organisms. Melanin plays a pivotal role in the existence of certain bacteria and fungi whereas in higher organisms it is a measure of protection against the harmful radiation. We have done a detailed study on various pathways known for melanin synthesis across species. It was divulged that melanin production is not restricted to tyrosine but there are other secondary metabolites that synthesize melanin in lower organisms. Furthermore the phylogenetic study of these paths was done to understand their molecular and cellular development. It has revealed that the melanin synthesis paths have co-evolved in several groups of organisms. In this study, we also introduce a method for the comparative analysis of a metabolic pathway to study its evolution based on similarity between enzymatic reactions.

30 citations

Journal ArticleDOI
10 Apr 2018
TL;DR: In this article, a compact stacked cylindrical dielectric resonator antenna (DRA) with a patch is proposed for wireless sensor network (WSN), which offers wide impedance bandwidth of 7.5GHz from 5.7 to 13.2GHz.
Abstract: In this article, a compact stacked cylindrical dielectric resonator antenna loaded with a patch is proposed for the wireless sensor network (WSN). Stacking of two dielectric material techniques is used to enhance the bandwidth of the antenna, and the metallic patch is used as a reflector for improving the gain and enforce compactness. The dielectric resonator antenna (DRA) is excited by the central coaxial probe feed with TM21 mode being observed at 6.7GHz resonant frequency. The proposed antenna is fabricated, and a close agreement is found between simulated and measured results. The proposed structure offers wide impedance bandwidth of 7.5GHz from 5.7 to 13.2GHz. A peak gain of 6.8 dBi is measured over the desired frequency band. The proposed DRA finds scenarios in WSNs and sensor node application.

16 citations


Cited by
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01 Aug 2000
TL;DR: Assessment of medical technology in the context of commercialization with Bioentrepreneur course, which addresses many issues unique to biomedical products.
Abstract: BIOE 402. Medical Technology Assessment. 2 or 3 hours. Bioentrepreneur course. Assessment of medical technology in the context of commercialization. Objectives, competition, market share, funding, pricing, manufacturing, growth, and intellectual property; many issues unique to biomedical products. Course Information: 2 undergraduate hours. 3 graduate hours. Prerequisite(s): Junior standing or above and consent of the instructor.

4,833 citations

Journal ArticleDOI

2,133 citations

Journal ArticleDOI
TL;DR: Insect prophenoloxidase has been studied for over a century, and the PPO activation cascade is becoming clearer, which suggests that it is time for us to look back on insect PPO beyond the view of immunity in this review.
Abstract: Insect prophenoloxidase (PPO) is an important innate immunity protein due to its involvement in cellular and humoral defense. It belongs to a group of type-3 copper-containing proteins that occurs in almost all organisms. Insect PPO has been studied for over a century, and the PPO activation cascade is becoming clearer. The insect PPO activation pathway incorporates several important proteins, including pattern-recognition receptors (PGRP, β GRP, and C-type lectins), serine proteases, and serine protease inhibitors (serpins). Due to their complexity, PPO activation mechanisms vary among insect species. Activated phenoloxidase (PO) oxidizes phenolic molecules to produce melanin around invading pathogens and wounds. The crystal structure of Manduca sexta PPO shows that a conserved amino acid, phenylalanine (F), can block the active site pocket. During activation, this blocker must be dislodged or even cleaved at the N-terminal sequence to expose the active site pockets and allow substrates to enter. Thanks to the crystal structure of M. sexta PPO, some domains and specific amino acids that affect PPO activities have been identified. Further studies of the relationship between PPO structure and enzyme activities will provide an opportunity to examine other type-3 copper proteins, and trace when and why their various physiological functions evolved. Recent researches show that insect PPO has a relationship with neuron activity, longevity, feces melanization (phytophagous insects) and development, which suggests that it is time for us to look back on insect PPO beyond the view of immunity in this review.

237 citations

Journal ArticleDOI
TL;DR: In this article, an experimental investigation was conducted to examine the effect of a pulsed Nd:YAG laser energy addition on the shock structures and surface pressure in a Mach 3.45 flow past a sphere.
Abstract: An experimental investigation was conducted to examine the effect of a pulsed Nd:YAG laser energy addition on the shock structures and surface pressure in a Mach 3.45 flow past a sphere. Two configurations were considered: 1) a sphere in a uniform freestream and 2) an Edney IV interaction generated by impingement of an oblique shock on the bow shock of the sphere

160 citations