Rahul Kumar - Profile on Academia.edu (original) (raw)

Papers by Rahul Kumar

Inter-particle coating variability in a continuous coater

Chemical Engineering Science, 2014

ABSTRACT The influence of particle axial motion on inter-particle coating variability is studied ... more ABSTRACT The influence of particle axial motion on inter-particle coating variability is studied in a rotating drum continuous coater. A mathematical framework based on renewal theory is developed and an expression for inter-particle coating variability is obtained that accounts for the variance in the residence time of particles inside the coater. This model makes no assumptions on the nature of the particle axial motion. Discrete element method simulations have shown, however, that the particle axial motion can be accurately modeled by a combination of advective and diffusive motion characterized by an axial Peclet number. Using this advective-diffusive model, it was found that in order to maintain an inter-particle coating variability of less than 1%, typical of what might be needed for functional pharmaceutical tablet coatings, a Peclet number of 20,000 is required. Such a large Peclet number would necessitate essentially plug flow for typical continuous coater lengths of 1–2 m, or coater lengths of at least 15 m for typical feed rates and spherical particle diffusion coefficients.

Simulation of various adaptive techniques in wireless: A comprehensive view

2015 2nd International Conference on Electronics and Communication Systems (ICECS), 2015

In this paper, we have analyzed the simulation of various adaptive techniques used in wireless co... more In this paper, we have analyzed the simulation of various adaptive techniques used in wireless communication as a comprehensive view. For this analysis we have derived the algorithm for least mean square (LMS), recursive least square (RLS) and minimum mean square error (MMSE). These adaptive filtering techniques are the best way to mitigate the effect of interference in a communication system. As the power of digital signal processors has increased, adaptive filters have become much more common and are now routinely used in devices such as mobile phones and other communication devices, camcorders and digital cameras, and medical monitoring equipment. Moreover, we have performed the simulation of LMS and RLS algorithm with their error rejection. We, hope that this paper will help both academic as well as industry research by providing the various adaptive techniques at one place along with their simulation result.

Functional genomics of tomato: Opportunities and challenges in post-genome NGS era

Journal of Biosciences, 2014

ABSTRACT The Tomato Genome Sequencing Project represented a landmark venture in the history of se... more ABSTRACT The Tomato Genome Sequencing Project represented a landmark venture in the history of sequencing projects where both Sanger's and next-generation sequencing (NGS) technologies were employed, and a highly accurate and one of the best assembled plant genomes along with a draft of the wild relative, Solanum pimpinellifolium, were released in 2012. However, the functional potential of the major portion of this newly generated resource is still undefined. The very first challenge before scientists working on tomato functional biology is to exploit this high-quality reference sequence for tapping of the wealth of genetic variants for improving agronomic traits in cultivated tomatoes. The sequence data generated recently by 150 Tomato Genome Consortium would further uncover the natural alleles present in different tomato genotypes. Therefore, we found it relevant to have a fresh outlook on tomato functional genomics in the context of application of NGS technologies in its post-genome sequencing phase. Herein, we provide an overview how NGS technologies vis-a-vis available reference sequence have assisted each other for their mutual improvement and how their combined use could further facilitate the development of other 'omics' tools, required to propel the Solanaceae research. Additionally, we highlight the challenges associated with the application of these cutting-edge technologies.

Computer Aided Verification, 2010

The Sdv Research Platform (Sdvrp) is a new academic release of Static Driver Verifier (Sdv) and t... more The Sdv Research Platform (Sdvrp) is a new academic release of Static Driver Verifier (Sdv) and the Slam software model checker that contains: (1) a parameterized version of Sdv that allows one to write custom API rules for APIs independent of device drivers; (2) thousands of Boolean programs generated by Sdv in the course of verifying Windows device drivers, including the functional and performance results (of the Bebop model checker) and test scripts to allow comparison against other Boolean program model checkers; (3) a new version of the Slam analysis engine, called Slam2, that is much more robust and performant.

Proceedings of the 11th Working Conference on Mining Software Repositories, 2014

With the growing complexity of modern day software, software model checking has become a critical... more With the growing complexity of modern day software, software model checking has become a critical technology for ensuring correctness of software. As is true with any promising technology, there are a number of tools for software model checking. However, their respective performance trade-offs are difficult to characterize accurately -making it difficult for practitioners to select a suitable tool for the task at hand. This paper proposes a technique called MUX that addresses the problem of selecting the most suitable software model checker for a given input instance. MUX performs machine learning on a repository of software verification instances. The algorithm selector, synthesized through machine learning, uses structural features from an input instance, comprising a program-property pair, at runtime and determines which tool to use. We have implemented MUX for Windows device drivers and evaluated it on a number of drivers and model checkers. Our results are promising in that the algorithm selector not only avoids a significant number of timeouts but also improves the total runtime by a large margin, compared to any individual model checker. It also outperforms a portfolio-based algorithm selector being used in Microsoft at present. Besides, MUX identifies structural features of programs that are key factors in determining performance of model checkers.

Systems Biology: Developments and Applications

Molecular Mechanisms in Yeast Carbon Metabolism, 2014

ABSTRACT Systems biology relies on systems theory concepts and is applicable to both fundamental ... more ABSTRACT Systems biology relies on systems theory concepts and is applicable to both fundamental studies of cellular biology as well as applied research such as metabolic engineering. In this chapter, we map the context of systems biology developments and highlight its contribution in understanding the yeast carbon metabolism. Systems biology not only contributes towards the global overview of metabolism but also in combination with an integrative analysis approach facilitates the elucidation of molecular mechanisms. In particular we discuss the role of systems biology in unraveling the molecular details concerning glucose and galactose metabolism. In conclusion, this chapter provides an overview of the progress and impact of systems biology in carbon metabolism. © Springer-Verlag Berlin Heidelberg 2014. All rights are reserved.

International Journal of Scientific Research, 2012

The developments in the means of transportation along with the communication advancements has mad... more The developments in the means of transportation along with the communication advancements has made the automotives to step into its next level of innovation by providing a safe, convenient and well-timed transportation. This is made possible by the introduction of the frame work that is particularly designed to establish connectivity between vehicles on road without any previous structure to support with. This paradigm formed particularly in organizing communication between vehicles is the vehicular Adhoc network (VANET) that causes a vehicles to vehicle connection for proper managing of the traffic flow to make the travel more safe and comfortable. The paper proposes a dynamic mapping of real time traffic with the acquisition of digital map by crowd mapping with clustering to offer path optimization to minimize the delay in the responses, for having an efficient traffic managing. The evaluation of the proposed methodology ensures the minimization of the delay in the communication and the improved delivery ratio incurred, when compared with the carry-forward based routings methods that cause more delay resulting in imperfect traffic management.

2008 IEEE International Symposium on Parallel and Distributed Processing, 2008

MPI Alltoall is one of the most communication intense collective operation used in many parallel ... more MPI Alltoall is one of the most communication intense collective operation used in many parallel applications. Recently, the supercomputing arena has witnessed phenomenal growth of commodity clusters built using InfiniBand and multi-core systems. In this context, it is important to optimize this operation for these emerging clusters to allow for good application scaling. However, optimizing MPI Alltoall on these emerging systems is not a trivial task. InfiniBand architecture allows for varying implementations of the network protocol stack. For example, the protocol can be totally on-loaded to a host processing core or it can be off-loaded onto the NIC or can use any combination of the two. Understanding the characteristics of these different implementations is critical in optimizing a communication intense operation such as MPI Alltoall. In this paper, we systematically study these different architectures and propose new schemes for MPI Alltoall tailored to these architectures. Specifically, we demonstrate that we cannot use one common scheme which performs optimally on each of these varying architectures. For example, on-loaded implementations can exploit multiple cores to achieve better network utilization, and in offload interfaces aggregation can be used to avoid congestion on multi-core systems. We employ shared memory aggregation techniques in these schemes and elucidate the impact of these schemes on multi-core systems. The proposed design achieves a reduction in MPI Alltoall time by 55% for 512Byte messages and speeds up the CPMD application by 33%.

Transplantation, 2007

Background. The cytomegalovirus (CMV) immune evasion genes US3, US6, and US11 may disrupt the hos... more Background. The cytomegalovirus (CMV) immune evasion genes US3, US6, and US11 may disrupt the host immune response via downregulation of major histocompatibility complex molecules. Transplant recipients with CMV infection were prospectively assessed for immune evasion gene expression. Methods. Seventy solid organ transplant patients with CMV infection who were given antiviral therapy were enrolled. Quantitative mRNA levels of US3, US6, and US11 were assessed using real-time polymerase chain reaction assays from peripheral blood mononuclear cells at regular time-points after starting therapy. Results. High immune evasion mRNA levels were detectable at start-of-therapy (median US3-4.5 log 10 copies; US6 -3.7 log 10 copies, and US11-3.3 log 10 copies/10 5 cells). With therapy, immune evasion mRNA levels declined exponentially. For example, median calculated US3 half-life was 1.59 days (range 0.74 -12.5 days). By day7, US3 mRNA was detectable in 55.7%, US6 in 38.6%, and US11 in 41.4% of patients. Early phase kinetics correlated with outcomes. When adjusted for baseline DNA level, there was a trend to higher mRNA levels in patients who relapsed. Also, detectable mRNA at day 14 after start of therapy was associated with virologic relapse after initial treatment (PՅ0.001 for US3, US6, and US11). For example, if US3 mRNA was still detectable at day 14, then risk of relapse was 84.2% vs. 29.4% if US3 mRNA not detectable at day 14 (PϽ0.001). This correlation was independent of the DNA viral load. CMV immune evasion gene expression is detectable at high levels in patients with CMV infection and declines exponentially with therapy. Expression levels can be independently correlated with outcomes.

Patulin causes DNA damage leading to cell cycle arrest and apoptosis through modulation of Bax, p53 and p21/WAF1 proteins in skin of mice

Toxicology and Applied Pharmacology, 2009

Patulin (PAT), a mycotoxin found in apples, grapes, oranges, pear and peaches, is a potent genoto... more Patulin (PAT), a mycotoxin found in apples, grapes, oranges, pear and peaches, is a potent genotoxic compound. WHO has highlighted the need for the study of cutaneous toxicity of PAT as manual labour is employed during pre and post harvest stages, thereby causing direct exposure ...

The Analyst, 2012

page 1.1 General Remarks 1 1.2 Synthesis of 2 and chemosensor 1 2-3 2. Spectra of 2 and chemosens... more page 1.1 General Remarks 1 1.2 Synthesis of 2 and chemosensor 1 2-3 2. Spectra of 2 and chemosensor 1 3-5 3. UV-Vis and fluorescence studies 6-7 4. HRMS and 1 HNMR analysis of 1 + ClO 4 -complex 8 5. Thermodynamic parameters 9 6. Crystal data 10-12 1. Experimental Details 1.1 General Remarks: All chemicals were obtained from common suppliers (Aldrich, Across, SDFCL, Spectrochem etc.) and used without further purification. 1-(4-bipenyl)benzimidazole (2) was synthesized by CuI, benzotriazole catalyzed N-arylation of benzimidazole with 4bromobiphenyl as reported in literature 1 . 1 H and 13 C NMR spectra were recorded on Brucker-400 and JEOL-300 instruments using the resonance of solvents having TMS as internal standard. Shifts are given in ppm; coupling constants in Hz. UV-Vis studies of compounds were

One-Pot, Two-Step Conversion of Aldehydes to Phosphonyl- and Sulfonylpyrazoles Using Bestmann–Ohira Reagent

Organic Letters, 2012

A one-pot, two-step, three-component method for the conversion of commercially available aldehyde... more A one-pot, two-step, three-component method for the conversion of commercially available aldehydes to phosphonylpyrazoles has been developed, demonstrating, for the first time, the dual reactivity of the Bestmann-Ohira reagent (BOR) in a single-pot transformation. This method, extended to the synthesis of sulfonylpyrazoles by employing BOR in the first step and a diazomethyl sulfone in the second step, is complementary, with regard to regioselectivity, to the previous methods for the synthesis of such functionalized pyrazoles.

Influence of nitrogen on the expression of TaDof1 transcription factor in wheat and its relationship with photo synthetic and ammonium assimilating efficiency

Molecular Biology Reports, 2009

Nitrogen is a crucial macronutrient needed in the greatest amount of all mineral elements require... more Nitrogen is a crucial macronutrient needed in the greatest amount of all mineral elements required by plants. Development of crop varieties with high nitrogen use efficiency (NUE) is imperative for sustainable agriculture. Understanding how plant genes respond to different nitrogen conditions is essential for formulating approaches, for manipulating genes, for improving NUE. In the present study we analyzed the activity of three different enzymes involved in nitrogen assimilation viz., GS, GOGAT and GDH along with physiological parameters like chlorophyll variable yield (Fv/Fmax), photosynthesis rate and total chlorophyll content at four different growth stages of wheat plant development under different nitrogen treatments. For this study two different wheat varieties UP-2644 and Raj-4097 having high and low protein content, respectively in the grains were chosen. Gene expression profile of a Dof transcription factor (TaDof1 of wheat) was also included in the study to assess its role in nitrogen metabolism. Densitometry analysis at S(2) and S(3) stage of wheat spikes of both the wheat varieties grown at different nitrogen treatments showed that TaDof1 expression was up-regulated in low nitrogen treatment. In S(3) stage, in high protein content wheat variety UP-2644, TaDof1 expression was elevated in low and normal nitrogen treatment as compared to high nitrogen treatment. The gene expression profile of Dof 1 was found to coincide with the enzyme activities of GS, GOGAT at the S(3) stage. The activities of these enzymes were prolonged in the high protein content variety. Since, Dof transcription factor(s) have been previously reported to control the expression of genes involved nitrogen assimilation i.e., GS and GOGAT and may be the elevated expression of Dof 1 at the grain filling stage over expresses the GS and GOGAT genes thereby prolonging their activities.

Microbial Cell Factories, 2011

Background: It is important to understand the cellular responses emanating from environmental per... more Background: It is important to understand the cellular responses emanating from environmental perturbations to redesign the networks for practical applications. In particular, the carbon (C) metabolism, nitrogen (N) assimilation, and energy generation are by far important, where those are interconnected and integrated to maintain cellular integrity. In our previous study, we investigated the effect of C/N ratio on the metabolic regulation of gdhA, glnL, glt B,D mutants as well as wild type Escherichia coli (Kumar and Shimizu, MCF, 1-17, 9:8,2010), where it was shown that the transcript levels of cyoA and cydB which encode the terminal oxidases, fnr and fur which encode global regulators were significantly up-regulated under N-limited condition as compared to C-limited condition. In the present study, therefore, the effects of such single-gene knockout on the metabolic regulation were investigated to clarify the roles of those genes in the aerobic continuous culture at the dilution rate of 0.2 h -1 . Results: The specific glucose consumption rates and the specific CO 2 production rates of cyoA, cydB, fnr, and fur mutants were all increased as compared to the wild type under both C-limited and N-limited conditions. The former phenomenon was consistent with the up-regulations of the transcript levels of ptsG and ptsH, which are consistent with down-regulations of crp and mlc genes. Moreover, the increase in the specific glucose consumption rate was also caused by up-regulations of the transcript levels of pfkA, pykF and possibly zwf, where those are consistent with the down regulations of cra, crp and mlc genes. Moreover, the transcript levels of rpoN together with glnK, glnB, glnE were upregulated, and thus the transcript levels of glnA,L,G, and gltB,D as well as nac were up-regulated, while gdhA was downregulated. This implies the interconnection between cAMP-Crp and P II -Ntr systems. Moreover, cyoA, cydB, fnr and fur gene deletions up-regulated the transcript levels of respiration (nuoA, ndh, cyoA, cydB, and atpA) and the oxidative stress related genes such as soxR, S and sodA, where this was further enhanced under N-limitation. In the cases of cyoA and cydB mutants, arcA, fnr, fur, cydB (for cyoA mutant), and cyoA (for cydB mutant) genes were up-regulated, which may be due to incomplete oxidation of quinol. It was also shown that fur gene transcript level was up-regulated in accordance with the activation of respiratory chain genes. It was shown that the deletion of fur gene activated the enterobactin pathway. The present result demonstrated how the fermentation characteristics could be explained by the transcript levels of metabolic pathway genes as well as global regulators in relation to the knockout of such single genes as cyoA, cydB, fnr, and fur, and clarified the complex gene network regulation in relation to glycolysis, TCA cycle, respiration, and N-regulated pathways. The present result is quite important in understanding the metabolic regulation for metabolic engineering. Moreover, the present result may be useful in improving the specific glucose consumption rate and activation of the TCA cycle by modulating the respiratory chain genes and the related global regulators. The result obtained under N-limited condition may be useful for the heterologous protein production under N-limitation.

In vitro and in vivo studies on degradation of quinalphos in rats

Journal of Hazardous Materials, 2012

A pharmacokinetic in vitro and in vivo degradation study has been carried out in rat to evaluate ... more A pharmacokinetic in vitro and in vivo degradation study has been carried out in rat to evaluate the deleterious effects of exposure to quinalphos on a target population. Degradation of quinalphos in simulated gastric and intestinal phases has been investigated. The metabolic intermediates of quinalphos in serum and urine of albino rats at different time intervals were identified after dosing the animals with 5 mg kg(-1) body weight. All the samples were lyophilised, extracted and analysed by HPLC and GC-MS. The rate of degradation of quinalphos was accelerated in the presence of the enzymes pepsin and pancreatin contained in the gastric and intestinal simulations, respectively. Quinalphos oxon, O-ethyl-O-quinoxalin-2-yl phosphoric acid, 2-hydroxy quinoxaline and ethyl phosphoric acid are among the important metabolites identified both in in vitro and in vivo investigations. In simulated in vitro study some isomerised derivatives which were missing in the blood and urine of treated animals were identified. This could possibly be either due to non-formation or faster decay of the isomerised derivatives because of slightly different conditions prevailing in the two cases. The results also indicate that the metabolites, 2-hydroxy quinoxaline and oxon, which are more toxic than the parent compound, seem to persist for a longer time.

Evaluation of LV Diastolic Function From Color M-Mode Echocardiography

JACC: Cardiovascular Imaging, 2011

ABSTRACT this study evaluated early diastolic filling dynamics using a semiautomated objective an... more ABSTRACT this study evaluated early diastolic filling dynamics using a semiautomated objective analysis of filling velocities obtained from color M-mode echocardiography. diastolic function can be evaluated from color M-mode echocardiography by measuring the early diastolic flow propagation velocity (Vp) from the slope of a single linear approximation of an isovelocity contour. However, this method has limitations and may not accurately represent diastolic filling. we used a semiautomated objective analysis of color M-mode echocardiograms from a development cohort of 125 patients with varying diastolic function to quantify left ventricular filling velocities. Early diastolic filling was not accurately described with a single propagation velocity; instead, the rapid initial filling velocity abruptly decelerated to a slower terminal velocity. Then, we evaluated a new measure of diastolic function in a separate group of 160 patients. compared with normal filling, diastolic dysfunction with restricted filling had a lower initial velocity (53 ± 21 cm/s vs. 87 ± 29 cm/s, p < 0.001), and the deceleration point occurred closer to the mitral annulus (2.4 ± 0.6 cm vs. 3.1 ± 0.7 cm, p < 0.05). The product of the initial velocity and the distance to the deceleration point from the mitral annulus, indicating the strength of the early filling (Vs), was progressively reduced with diastolic dysfunction. In a separate validation cohort of 160 patients, Vs better recognized diastolic dysfunction (classified by reduced diastolic intraventricular pressure gradient, elevated pulmonary capillary wedge pressure, or elevated B-type natriuretic peptide) than Vp did. early diastolic flow propagation occurs with an initial rapid velocity that abruptly decelerates to a terminal velocity. With diastolic dysfunction, the initial velocity is slower and the deceleration point occurs closer to the mitral annulus than with normal filling. A new parameter that combines these 2 effects (Vs) provides a more accurate assessment of diastolic function than the conventional propagation velocity.

Characterization and molecular mapping of EMS-induced brittle culm mutants of diploid wheat (Triticum monococcum L.)

Euphytica, 2011

ABSTRACT Diploid wheat (Triticum monococcum L, AmAm) is an ideal material for induced mutations w... more ABSTRACT Diploid wheat (Triticum monococcum L, AmAm) is an ideal material for induced mutations which can be easily characterized and transferred to polyploid wheats. The EMS-induced brittle culm mutants, brc1, brc2, and brc3 used in the present investigation, were isolated from T. monococcum. All the brittle mutants had brittle roots, leaves, leaf sheaths, culms, and spikes, and were also susceptible to lodging. The mutants had 47–57% reduced a-cellulose in the secondary cell walls than that of T. monococcum indicating that all of them had defective synthesis of cellulose. All the mutants were monogenic recessive. Bulk segregation analysis of the mutants, using Am genome anchored SSR markers in their F2 populations with T. boeoticum, located the mutants, brc1, brc2, and brc3 on chromosome 6A, 3A, and 1A of T. monococcum, respectively. Molecular analysis of the putatively linked markers showed that brc1 mapped on chromosome 6AS between Xbarc37 and Xbarc113 markers, brc2 on chromosome 3AL between Xcfd62 and Xcfa2170 markers whereas brc3 mapped on chromosome 1AL between Xgwm135 and Xwmc470 markers. Isolation and mapping of three different brittle culm mutants in wheat for the first time shows that there might be many more genes in wheat which affect synthesis and deposition of cellulose.

Euphytica, 2010

A traditional Type 3 Basmati rice cultivar grown in India is tall and lodges even under low nitro... more A traditional Type 3 Basmati rice cultivar grown in India is tall and lodges even under low nitrogen fertilizer dose. In addition to lodging, it is highly susceptible to several diseases and pests including bacterial blight (BB). BB resistance genes (Xa21 and xa13) and a semidwarfing gene (sd-1) were pyramided in Type 3 Basmati from a rice cultivar PR106-P2 using marker-assisted selection (MAS). Foreground selection for BB resistance genes, Xa21 and xa13 and reduced plant height gene, sd-1 was carried on the basis of linked molecular markers pTA248, RG136 and 'h', respectively. The BC 2 F 3 progenies with both the BB resistance genes were highly resistant with lower lesion length than either of the genes individually. Background profiling of the selected 16 BC 2 F 3 progenies was done using 95 anchored SSR and 12 ISSR markers. Among the selected 16 BC 2 F 3 progenies, 38-5-2 and 38-5-36 closely clustered along with the recipient parent Type 3 Basmati showing above 85% genetic similarity with the same. Further selection was continued till F 5 generation for higher recovery for Type 3 Basmati characteristics. The desirable alleles of intermediate amylose content (wx) and aroma (fgr) loci of Type 3 Basmati were also tracked using the linked SSR markers. The BC 2 F 5 pyramid lines T3-4, T3-5, T3-6 and T3-7 homozygous for the three target genes Xa21, xa13 and sd-1 from the donor parent with wx and fgr alleles of Type 3 Basmati had excellent cooking quality and strong aroma.

Education and Information Technologies, 2003

CYP11B2 gene haplotypes independently and in concurrence with aldosterone and aldosterone to renin ratio increase the risk of hypertension

Clinical Biochemistry, 2010

Aldosterone synthase produces aldosterone, which regulates electrolytes and thereby blood pressur... more Aldosterone synthase produces aldosterone, which regulates electrolytes and thereby blood pressure. Polymorphisms in aldosterone-synthase gene (CYP11B2) may associate with heterogeneous aldosterone production and hypertension. Hence, we investigated -344T/C, Iw/Ic polymorphisms of CYP11B2, plasma renin activity (PRA) and aldosterone concentration (PAC). Consecutive ethnically-matched 450 hypertensive patients and 360 controls were screened by PCR-RFLP for genotypes and haplotypes; PRA and PAC were measured. The Iw/Ic polymorphism distribution differed significantly between the two groups (LRT chi(2)=15.8, df=2, P=0.000). The mutant allele-Ic and genotype-Ic/Ic were overrepresented in patients (35% versus 27% and 13% versus 7%). Overrepresentation of T-Ic haplotype in patients was identified as risk haplotype (P=0.000). Patients had significantly higher PAC and aldosterone-to-renin ratio (ARR; P=0.000), which was Ic-allele dependent. The haplotype T-Ic associated with hypertension susceptibility. Correlation between Ic-allele and raised ARR likely serve in hypertension management.