vijay kumar - Academia.edu (original) (raw)
Papers by vijay kumar
International Journal of Dermatology, 1985
Cytoid bodies are colloid bodies that bind IgM cind/or other Ig .ind fibrin as seen by direct imm... more Cytoid bodies are colloid bodies that bind IgM cind/or other Ig .ind fibrin as seen by direct immunofluorescent (IF) staining of skin sections (Fig. 1.) These cytoid bodies occur commonly in association with hydropic degeneration of (he basal cells, most notably in lichen planus and lupus erythematosus.''' In lichen planus, cytoid body formation is accompanied frequently by fibrin deposits at the dermal-epidermal junction. Cytoid bodies also occur in other dermatoses, such as systemic lupus, buiious pemphignid, and erythemii multiforme. Rare, smnll cytoid bodies may even bo found In normal skin/' Most immunopathologists agree that cytoid bodies develop from injured keratinocytes. ludging by their frequent occurrence, it appears that cyloid body formation is a common response of keratinocytes to injury. Their appearance not only in the epidermis and cit the dermal-epidermal junction but also in the dermis suggests that cytoid body formation is probably a stage in apoptosis"'' (ie, a part of a mechanism by which injured or dead keratinocytes can be removed via the systemic circulation by moving downward through the epidermis and into dermis rather than removal by upward movement and exfoliation from the surface of the horny layer). The apoptosis appears to be mediated by the ARM as described below. Il is important that acid elution of cytoid bodybearing sections of skin removes the Ig; that is, treatment of sections with pH 2 citrate buffer before direct immunofluorescent staining renders cytoid bodies IF-negative, a reaction pattern suggestive of antibody binding. Not all colloid bodies detected in routine histologic studies appear as cytoid bodies.
The Indian Journal of Pediatrics, 1991
To improve the quality of MCH services, a Home Based Mothers Card (HBMC) prepared and recommended... more To improve the quality of MCH services, a Home Based Mothers Card (HBMC) prepared and recommended by World Health Organization was adapted to Indian situation, and introduced in 1.5 lakh population of rural area covered by 6 participating centres under the aegis of Indian Council of Medical Research. Two thousand four hundred and forty six mothers were given this card and were followed up for a period of 2 years. Only 89.2 percent retrieval of the cards was possible after a period of 18 months. Screening of the population for "at risk" women monitoring and referral could be undertaken with the help of this card. Improved antenatal, and referral services were observed during the study period. The card (HBMC) was acceptable to the mothers as well as to the health workers, as a tool for improving the quality and coverage of MCH services being rendered at the Primary Health Centre.
Proceedings 2003 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2003) (Cat. No.03CH37453)
Robot programmers can often quickly program a robot to approximately execute a task under specifi... more Robot programmers can often quickly program a robot to approximately execute a task under specific environment conditions. However, achieving robust performance under more general conditions is significantly more difficult. We propose a framework that starts with an existing control system and uses reinforcement feedback from the environment to autonomously improve the controller's performance. We use the Policy Gradient Reinforcement Learning (PGRL) framework, which estimates a gradient (in controller space) of improved reward, allowing the controller parameters to be incrementally updated to autonomously achieve locally optimal performance. Our approach is experimentally verified on a Cye robot executing a room entry and observation task, showing significant reduction in task execution time and robustness with respect to un-modelled changes in the environment.
2009 IEEE International Conference on Robotics and Automation, 2009
In this paper, we present three designs for a decoupled, two-dimensional, vision-based µN force s... more In this paper, we present three designs for a decoupled, two-dimensional, vision-based µN force sensor for microrobotic applications. There are currently no reliable, off-the-shelf, commercially-available force sensors to measure forces at this scale, that can be easily integrated into standard microrobotic test-beds. In our previous work, we presented a design consisting of a planar, elastic mechanism with known force-deflection characteristics. It was inspired by the designs of pre-existing MEMS suspension mechanisms. A CCD camera is used to track the deformation of the mechanism as it is used to manipulate objects in a micro/meso-scale robotic manipulation test-bed. By observing the displacements of select points in the mechanism, the manipulation forces can be estimated. Here, a building block approach for conceptual synthesis of compliant mechanisms methodology is used to design for decoupled displacements for the tracking points when the tip is subjected to forces in the XY-plane. By designing mechanisms with circular compliance and stiffness ellipses along with zero magnitude compliance and stiffness vectors, we are able to achieve our design requirements. Validation of this approach with macro-scale prototypes and recommendations for scaling the designs down for microrobotic applications are offered along with a sensitivity analysis of the final designs yielding insights for microfabricating such designs.
Tetrahedron Letters, 2002
Indole derivatives Indole derivatives R 0140 Novel Indium-Mediated Deoxygenative α,α-Diallylation... more Indole derivatives Indole derivatives R 0140 Novel Indium-Mediated Deoxygenative α,α-Diallylation of Indole-and Pyrrole-3-carboxaldehydes.-Generally, the title reaction affords dienic derivatives. Interestingly, in the case of indole (IV), the usual 1,2-addition product is isolated.-(
Communications in Computer and Information Science, 2010
SK Prasad et al. (Eds.): ICISTM 2010, CCIS 54, pp. 339347, 2010. © Springer-Verlag Berlin Heidel... more SK Prasad et al. (Eds.): ICISTM 2010, CCIS 54, pp. 339347, 2010. © Springer-Verlag Berlin Heidelberg 2010 ... Swarm Optimization and A Comparative Study Using ... Girish Parmar1, Mahendra K. Pandey2, and Vijay Kumar3 ... 1 Department of Electronics Engineering, ...
Indian journal of pathology & microbiology, 2004
Filariasis is endemic in southern Asia, with Wuchereria bancrofti accounting for over 90% of in-f... more Filariasis is endemic in southern Asia, with Wuchereria bancrofti accounting for over 90% of in-fectionsl. Breast is an unusual site of affectation in filariasis and presence of this infection in fine needle aspirate (FNA) has been documented in the,form of case reports only2,3. The gravid adult worm has been described even on fewer occasions in FNA3. We describe one such interesting case
Sensors and Actuators A: Physical, 2011
We present a two-dimensional, vision-based force sensor, capable of sensing micro-Newton level fo... more We present a two-dimensional, vision-based force sensor, capable of sensing micro-Newton level forces for use in microrobotic applications. Our design consists of a planar, elastic mechanism with known force-deflection characteristics. A CCD camera attached to an optical microscope is used to track the deformation of the mechanism as it is used to manipulate objects in a microrobotic test-bed. By observing the displacements of select points in the mechanism, the manipulation forces can be extracted in realtime to achieve force-guided manipulation of micro-scale objects. The modeling, design, microfabrication, calibration and experimental validation of the force sensor for use in a microassembly application are presented here along with preliminary results for next generation designs.
Radiation Physics and Chemistry, 1998
Journal of the American Academy of Dermatology, 1985
Our immunologic studies of twenty-five patients with acrosclerosis with severe acral involvement,... more Our immunologic studies of twenty-five patients with acrosclerosis with severe acral involvement, twenty-seven patients with most or all of the signs of CREST syndrome, twenty-two patients with systemic lupus erythematosus as positive controls, and ninety-one blood donors as negative controls centered on an evaluation of eight antigenic substrates, including four types of human cells for the detection of anticentromere antibodies (ACA) and other antinuclear antibodies (ANA). The ACA, which occurred only among the patients with most or all of the signs of CREST syndrome, could be detected reliably on human cell lines HEp-2 and KB but not on a mouse cell line or on the three types of tissue sections examined. Comparisons of human HEp-2 and KB cell lines from four sources indicated that HEp-2 cells are the best of the substrates tested for detection of ACA. Since rodent tissue sections give negative reactions with ACA, they are indicated for confirmation. In general, results varied with the type and source of antigen used. Thus ANA findings need to be expressed not only in terms of the titers of the antibodies and the pattern(s) of their reactions but also in terms of the type of antigen or substrate used, its source, and the diagnostic significance of findings in the given test system.
Journal of Materials Science: Materials in Electronics, 2010
In this paper, electrochemical fabrication and characterization of CdS nanowires having diameter ... more In this paper, electrochemical fabrication and characterization of CdS nanowires having diameter 100 and 200 nm is reported. Nano-channels in anodic alumina membrane were utilized as template. Morphological study of nanowires was made using Scanning electron microscopy (SEM). UV-visible absorption and laser induced time resolved photoluminescence (PL) spectroscopy were used for optical characterization. UV-visible absorption depicts that, there is slight increase in band gap of nanowires with decrease in diameter of nanowires. PL measurements indicate emission band peak of 435 and 420 nm in case of 200 and 100 nm wires respectively. These studies are very important regarding the synthesis and optoelectronic applications of CdS nanowires.
Journal of Materials Chemistry, 2004
Indian Journal of Medical Microbiology, 2014
Extensive research on biofilm forming pathogens has opened new avenues in exploring the role of t... more Extensive research on biofilm forming pathogens has opened new avenues in exploring the role of these operons in biofilm expression and regulation. The current review is focused on various operons and their functions which are reported in device-associated pathogens such as S. aureus, S. epidermidis and P. aeruginosa. These operons are also regulated by various transcription and global regulators. A short description on well-reported transcriptional and global regulators of Staphylococcus and Pseudomonas aeruginosa biofilms have been explained in this review.
Writing robust high level controllers for robots in unstructured environments is extremely diffic... more Writing robust high level controllers for robots in unstructured environments is extremely difficult for human designers. One can often design a controller that accomplishes a task under a limited set of circumstances, but the effort of tuning and refinement required to achieve robustness under more general conditions is prohibitive. We propose a framework that starts with an existing control system and uses reinforcement feedback from the environment to autonomously improve the controller's performance. Our approach ...
The International Journal of Robotics Research, 2014
In this paper, we consider the problem of concurrent assignment and planning of trajectories (whi... more In this paper, we consider the problem of concurrent assignment and planning of trajectories (which we denote Capt ) for a team of robots. This problem involves simultaneously addressing two challenges: (1) the combinatorially complex problem of finding a suitable assignment of robots to goal locations, and (2) the generation of collision-free, time parameterized trajectories for every robot. We consider the Capt problem for unlabeled (interchangeable) robots and propose algorithmic solutions to two variations of the Capt problem. The first algorithm, c-Capt, is a provably correct, complete, centralized algorithm which guarantees collision-free optimal solutions to the Capt problem in an obstacle-free environment. To achieve these strong claims, c-Capt exploits the synergy obtained by combining the two subproblems of assignment and trajectory generation to provide computationally tractable solutions for large numbers of robots. We then propose a decentralized solution to the Capt pr...
International Journal of Dermatology, 1985
Cytoid bodies are colloid bodies that bind IgM cind/or other Ig .ind fibrin as seen by direct imm... more Cytoid bodies are colloid bodies that bind IgM cind/or other Ig .ind fibrin as seen by direct immunofluorescent (IF) staining of skin sections (Fig. 1.) These cytoid bodies occur commonly in association with hydropic degeneration of (he basal cells, most notably in lichen planus and lupus erythematosus.''' In lichen planus, cytoid body formation is accompanied frequently by fibrin deposits at the dermal-epidermal junction. Cytoid bodies also occur in other dermatoses, such as systemic lupus, buiious pemphignid, and erythemii multiforme. Rare, smnll cytoid bodies may even bo found In normal skin/' Most immunopathologists agree that cytoid bodies develop from injured keratinocytes. ludging by their frequent occurrence, it appears that cyloid body formation is a common response of keratinocytes to injury. Their appearance not only in the epidermis and cit the dermal-epidermal junction but also in the dermis suggests that cytoid body formation is probably a stage in apoptosis"'' (ie, a part of a mechanism by which injured or dead keratinocytes can be removed via the systemic circulation by moving downward through the epidermis and into dermis rather than removal by upward movement and exfoliation from the surface of the horny layer). The apoptosis appears to be mediated by the ARM as described below. Il is important that acid elution of cytoid bodybearing sections of skin removes the Ig; that is, treatment of sections with pH 2 citrate buffer before direct immunofluorescent staining renders cytoid bodies IF-negative, a reaction pattern suggestive of antibody binding. Not all colloid bodies detected in routine histologic studies appear as cytoid bodies.
The Indian Journal of Pediatrics, 1991
To improve the quality of MCH services, a Home Based Mothers Card (HBMC) prepared and recommended... more To improve the quality of MCH services, a Home Based Mothers Card (HBMC) prepared and recommended by World Health Organization was adapted to Indian situation, and introduced in 1.5 lakh population of rural area covered by 6 participating centres under the aegis of Indian Council of Medical Research. Two thousand four hundred and forty six mothers were given this card and were followed up for a period of 2 years. Only 89.2 percent retrieval of the cards was possible after a period of 18 months. Screening of the population for "at risk" women monitoring and referral could be undertaken with the help of this card. Improved antenatal, and referral services were observed during the study period. The card (HBMC) was acceptable to the mothers as well as to the health workers, as a tool for improving the quality and coverage of MCH services being rendered at the Primary Health Centre.
Proceedings 2003 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2003) (Cat. No.03CH37453)
Robot programmers can often quickly program a robot to approximately execute a task under specifi... more Robot programmers can often quickly program a robot to approximately execute a task under specific environment conditions. However, achieving robust performance under more general conditions is significantly more difficult. We propose a framework that starts with an existing control system and uses reinforcement feedback from the environment to autonomously improve the controller's performance. We use the Policy Gradient Reinforcement Learning (PGRL) framework, which estimates a gradient (in controller space) of improved reward, allowing the controller parameters to be incrementally updated to autonomously achieve locally optimal performance. Our approach is experimentally verified on a Cye robot executing a room entry and observation task, showing significant reduction in task execution time and robustness with respect to un-modelled changes in the environment.
2009 IEEE International Conference on Robotics and Automation, 2009
In this paper, we present three designs for a decoupled, two-dimensional, vision-based µN force s... more In this paper, we present three designs for a decoupled, two-dimensional, vision-based µN force sensor for microrobotic applications. There are currently no reliable, off-the-shelf, commercially-available force sensors to measure forces at this scale, that can be easily integrated into standard microrobotic test-beds. In our previous work, we presented a design consisting of a planar, elastic mechanism with known force-deflection characteristics. It was inspired by the designs of pre-existing MEMS suspension mechanisms. A CCD camera is used to track the deformation of the mechanism as it is used to manipulate objects in a micro/meso-scale robotic manipulation test-bed. By observing the displacements of select points in the mechanism, the manipulation forces can be estimated. Here, a building block approach for conceptual synthesis of compliant mechanisms methodology is used to design for decoupled displacements for the tracking points when the tip is subjected to forces in the XY-plane. By designing mechanisms with circular compliance and stiffness ellipses along with zero magnitude compliance and stiffness vectors, we are able to achieve our design requirements. Validation of this approach with macro-scale prototypes and recommendations for scaling the designs down for microrobotic applications are offered along with a sensitivity analysis of the final designs yielding insights for microfabricating such designs.
Tetrahedron Letters, 2002
Indole derivatives Indole derivatives R 0140 Novel Indium-Mediated Deoxygenative α,α-Diallylation... more Indole derivatives Indole derivatives R 0140 Novel Indium-Mediated Deoxygenative α,α-Diallylation of Indole-and Pyrrole-3-carboxaldehydes.-Generally, the title reaction affords dienic derivatives. Interestingly, in the case of indole (IV), the usual 1,2-addition product is isolated.-(
Communications in Computer and Information Science, 2010
SK Prasad et al. (Eds.): ICISTM 2010, CCIS 54, pp. 339347, 2010. © Springer-Verlag Berlin Heidel... more SK Prasad et al. (Eds.): ICISTM 2010, CCIS 54, pp. 339347, 2010. © Springer-Verlag Berlin Heidelberg 2010 ... Swarm Optimization and A Comparative Study Using ... Girish Parmar1, Mahendra K. Pandey2, and Vijay Kumar3 ... 1 Department of Electronics Engineering, ...
Indian journal of pathology & microbiology, 2004
Filariasis is endemic in southern Asia, with Wuchereria bancrofti accounting for over 90% of in-f... more Filariasis is endemic in southern Asia, with Wuchereria bancrofti accounting for over 90% of in-fectionsl. Breast is an unusual site of affectation in filariasis and presence of this infection in fine needle aspirate (FNA) has been documented in the,form of case reports only2,3. The gravid adult worm has been described even on fewer occasions in FNA3. We describe one such interesting case
Sensors and Actuators A: Physical, 2011
We present a two-dimensional, vision-based force sensor, capable of sensing micro-Newton level fo... more We present a two-dimensional, vision-based force sensor, capable of sensing micro-Newton level forces for use in microrobotic applications. Our design consists of a planar, elastic mechanism with known force-deflection characteristics. A CCD camera attached to an optical microscope is used to track the deformation of the mechanism as it is used to manipulate objects in a microrobotic test-bed. By observing the displacements of select points in the mechanism, the manipulation forces can be extracted in realtime to achieve force-guided manipulation of micro-scale objects. The modeling, design, microfabrication, calibration and experimental validation of the force sensor for use in a microassembly application are presented here along with preliminary results for next generation designs.
Radiation Physics and Chemistry, 1998
Journal of the American Academy of Dermatology, 1985
Our immunologic studies of twenty-five patients with acrosclerosis with severe acral involvement,... more Our immunologic studies of twenty-five patients with acrosclerosis with severe acral involvement, twenty-seven patients with most or all of the signs of CREST syndrome, twenty-two patients with systemic lupus erythematosus as positive controls, and ninety-one blood donors as negative controls centered on an evaluation of eight antigenic substrates, including four types of human cells for the detection of anticentromere antibodies (ACA) and other antinuclear antibodies (ANA). The ACA, which occurred only among the patients with most or all of the signs of CREST syndrome, could be detected reliably on human cell lines HEp-2 and KB but not on a mouse cell line or on the three types of tissue sections examined. Comparisons of human HEp-2 and KB cell lines from four sources indicated that HEp-2 cells are the best of the substrates tested for detection of ACA. Since rodent tissue sections give negative reactions with ACA, they are indicated for confirmation. In general, results varied with the type and source of antigen used. Thus ANA findings need to be expressed not only in terms of the titers of the antibodies and the pattern(s) of their reactions but also in terms of the type of antigen or substrate used, its source, and the diagnostic significance of findings in the given test system.
Journal of Materials Science: Materials in Electronics, 2010
In this paper, electrochemical fabrication and characterization of CdS nanowires having diameter ... more In this paper, electrochemical fabrication and characterization of CdS nanowires having diameter 100 and 200 nm is reported. Nano-channels in anodic alumina membrane were utilized as template. Morphological study of nanowires was made using Scanning electron microscopy (SEM). UV-visible absorption and laser induced time resolved photoluminescence (PL) spectroscopy were used for optical characterization. UV-visible absorption depicts that, there is slight increase in band gap of nanowires with decrease in diameter of nanowires. PL measurements indicate emission band peak of 435 and 420 nm in case of 200 and 100 nm wires respectively. These studies are very important regarding the synthesis and optoelectronic applications of CdS nanowires.
Journal of Materials Chemistry, 2004
Indian Journal of Medical Microbiology, 2014
Extensive research on biofilm forming pathogens has opened new avenues in exploring the role of t... more Extensive research on biofilm forming pathogens has opened new avenues in exploring the role of these operons in biofilm expression and regulation. The current review is focused on various operons and their functions which are reported in device-associated pathogens such as S. aureus, S. epidermidis and P. aeruginosa. These operons are also regulated by various transcription and global regulators. A short description on well-reported transcriptional and global regulators of Staphylococcus and Pseudomonas aeruginosa biofilms have been explained in this review.
Writing robust high level controllers for robots in unstructured environments is extremely diffic... more Writing robust high level controllers for robots in unstructured environments is extremely difficult for human designers. One can often design a controller that accomplishes a task under a limited set of circumstances, but the effort of tuning and refinement required to achieve robustness under more general conditions is prohibitive. We propose a framework that starts with an existing control system and uses reinforcement feedback from the environment to autonomously improve the controller's performance. Our approach ...
The International Journal of Robotics Research, 2014
In this paper, we consider the problem of concurrent assignment and planning of trajectories (whi... more In this paper, we consider the problem of concurrent assignment and planning of trajectories (which we denote Capt ) for a team of robots. This problem involves simultaneously addressing two challenges: (1) the combinatorially complex problem of finding a suitable assignment of robots to goal locations, and (2) the generation of collision-free, time parameterized trajectories for every robot. We consider the Capt problem for unlabeled (interchangeable) robots and propose algorithmic solutions to two variations of the Capt problem. The first algorithm, c-Capt, is a provably correct, complete, centralized algorithm which guarantees collision-free optimal solutions to the Capt problem in an obstacle-free environment. To achieve these strong claims, c-Capt exploits the synergy obtained by combining the two subproblems of assignment and trajectory generation to provide computationally tractable solutions for large numbers of robots. We then propose a decentralized solution to the Capt pr...