Livistona chinensis is used as an anticancer agent in traditional Chinese medicine. In vitro, the... more Livistona chinensis is used as an anticancer agent in traditional Chinese medicine. In vitro, the extracts of fruits and seeds of L. chinensis are known to possess antiangiogenic and antiproliferative activities. Here we report the presence of phenolic compounds in L. chinensis fruits which show hemolytic activity. The hemolytic activity of phenolics is limited to an acid-precipitable fraction. Further, presence of proteins and lipids abrogated the hemolytic activity indicating astringent and membrane damaging activities as mechanisms of hemolysis. In conclusion, the hemolytic activity of phenolics in L. chinensis fruits is due to astringent and membrane damaging activities.
A Lead salt midinfrared quantum-well (QW) laser on [110] orientation is proposed. Theoretical sim... more A Lead salt midinfrared quantum-well (QW) laser on [110] orientation is proposed. Theoretical simulations of [110] QW edge-emitting lasers show a 70° temperature increase in continuous-wave operation compared to the conventional [100]-orientated lasers. This is because the gain on [100]-orientated QW structure is significantly increased. Among [100], [111], and [110] orientations, [110]-orientated QW structure offers the highest gain. PbSe/PbSrSe QW structures were successfully grown on [110]-orientated BaF2 substrate by molecular-beam-epitaxy (MBE). Photoluminescence intensity of [110]-orientated samples was twice as high as that on [111]-orientated BaF2 substrates from the same MBE run.
PbSe thin film and PbSe/PbSrSe multiple quantum well (MQW) structures were successfully grown on ... more PbSe thin film and PbSe/PbSrSe multiple quantum well (MQW) structures were successfully grown on (1 1 0) BaF 2 substrates by molecular beam epitaxy. The average linewidth of the rocking curve from high-resolution X-ray diffraction measurements of the (2 2 0) reflection for the PbSe thin film was 60 arcsec, which indicates high crystalline quality. The dislocation density estimated from the rocking curve was 1 Â 10 7 cm À2 . Strong photoluminescence (PL) of the MQW structure at room temperature was observed. This PL signal was two times larger than those measured from a duplicate structure grown at the same time on a (1 1 1) BaF 2 substrate. The energy bandgap of (1 1 0) PbSe follows the same temperature dependence as [1 0 0]-and [1 1 1]-orientated PbSe. r
Abstract: The effect of plant growth regulators on callus induction using different explants, to ... more Abstract: The effect of plant growth regulators on callus induction using different explants, to regenerate shoot/root from different explants as well as from calli in cultures of Catharanthus roseus (L.) G. Don was studied. Total of nineteen shoot regeneration media were used, ...
ABSTRACT Assessment of soil organic C (SOC) stocks is important for monitoring the effect of land... more ABSTRACT Assessment of soil organic C (SOC) stocks is important for monitoring the effect of land use change in the C cycle and for formulation of C sequestration strategies in the context of global climate change. Discrepancies among the recent global SOC estimates by different researchers underscore the importance of precise estimation of the uncertainty associated with the SOC stocks. A method was recently proposed to estimate the SOC storage uncertainty using the Taylor series of approximations. Here we show that the accuracy of SOC storage uncertainty can be improved by incorporating the covariance among the input variables. Measurement of input variables from independent samples or use of an incomplete model leads to either over-or underestimation of the SOC storage uncertainty. The application of the method to an experimental data set indicated that ignoring covariance would lead to a substantial overestimate of the uncertainty.
| Infertile men are frequently affected by physical abnormalities that might be detected on routi... more | Infertile men are frequently affected by physical abnormalities that might be detected on routine general and genital examinations. These structural abnormalities might damage or block the testes, epididymis, seminal ducts or other reproductive structures and can ultimately decrease fertility. Physical deformities are variable in their pathological impact on male reproductive function; some render men totally sterile, such as bilateral absence of the vasa deferentia, while others cause only mild alterations in semen parameters. Concise and up-to-date information regarding the contemporary epidemiological characteristics, clinical features and pathophysiological impacts of these common abnormalities on male fertility is crucial for the practicing urologist to identify the best treatment option.
Isolated esophageal tuberculosis is very rare. We report a patient who presented with history of ... more Isolated esophageal tuberculosis is very rare. We report a patient who presented with history of retrosternal pain and dysphagia and on investigation was found to have a smooth esophageal mass. Endoscopic biopsy showed epitheloid cell granuloma with necrosis suggestive of tuberculosis. CT scan of the thorax showed no involvement of adjacent structures. The patient responded to antitubercular therapy.
Efficacy of doramectin administered via oral and parenteral routes against experimentally induced... more Efficacy of doramectin administered via oral and parenteral routes against experimentally induced and natural infections of the copepod parasite Lernaea cyprinacea in carps was studied. Administration of doramectin incorporated in feed at 1 mg/kg b.wt. of fish for 10 days effectively controlled experimentally induced Lernaea infection in Labeo fimbriatus fingerlings within an average of 19 days of post-treatment as compared to the normal course of 41 days. Similarly, doramectin given through feed at 1 mg/kg b.wt. of fish for 10 days was equally effective in controlling natural infection of this parasite in the underyearlings of Catla catla and L. fimbriatus. Intramuscular administration of doramectin at 200 mg/kg b.wt. of fish effectively removed adult Lernaea infection in L. fimbriatus as early as 18 days of treatment as compared to the time period of 43 days taken by the untreated fish to get rid of the infection. Single intramuscular administration of the drug was more effective against the parasite than its administration in multiple divided doses. In all cases, doramectin did not cause any noticeable adverse reactions or toxicity to the fish host. In view of the handling associated stress and other operational difficulties involved, a single intramuscular administration of the drug at 200 mg/ kg b.wt. is suggested for treatment of heavily infected adults and brood stock of carps. Doramectin incorporated in feed at 1 mg/ kg b.wt. of fish is best suited for treatment of Lernaea infection in young fish including fingerlings. However, detailed studies on the toxicity and pharmacokinetics of doramectin upon its administration to aquatic organisms and the environmental impact of its usage are required to be undertaken before finally recommending the safe use of this drug for control of parasitic infections of aquatic organisms. #
Thyroid hormones, previously thought not to affect spermatogenesis and male fertility, are now be... more Thyroid hormones, previously thought not to affect spermatogenesis and male fertility, are now being recognized as having important role in spermatogenesis. The identification of thyroid hormone receptors on Sertoli cells, the nurturing cells for sperm in the testis, has embarked further research to investigate the role of thyroid hormones in male reproduction. Since spermatogenesis occurs in close contact with the Sertoli cells, the thyroid hormones must exert significant regulatory role in sperm production. Therefore, disturbances in the thyroid function could affect spermatogenesis and male fertility. Studies on human subjects and animals models are now revealing further insights into the effect of thyroid hormones on male fertility and infertility. The present review provides an update on the role of thyroid hormones in spermatogenesis and male fertility.
Stress produces definable mental and physiological reactions in the body. Mild stress is benefici... more Stress produces definable mental and physiological reactions in the body. Mild stress is beneficial in cognitive tasks and performance but persistently high stress may lead to neuropsychiatric illnesses like anxiety and depression. Examinations act as stressor and activate hypothalamicpituitary adrenal axis causing an increase in cortisol level, which is reflected in saliva. Present study was done on 35 medical students. Their mood parameters were assessed, using Depression Anxiety Stress Scale (DASS) scoring, and salivary cortisol levels using quantitative ELISA. Subjects were evaluated for mood parameters two times, one during relaxed state (with no examinations in preceding 2 weeks and in coming 2 weeks) and another during stressed state (on the day of viva voce examination). The levels of mood parameters and salivary cortisol were significantly raised during examination stress. The changes in stress level significantly correlated with change in levels of anxiety and salivary cortisol though there was no significant effect on the performance. Males and females showed similar changes in mood parameters. This study suggests that as examinations act as unavoidable stressors, the medical educators as well as students should be made aware of the negative consequences of stress faced during medical training. Efficient relaxation program as well as counseling services should be provided to stressed students so that they are able to cope better with examination stress.
In grinding process, a stiff air layer is generated around the wheel due to rotation of porous gr... more In grinding process, a stiff air layer is generated around the wheel due to rotation of porous grinding wheel at high speed. This stiff air layer restricts fluid to reach deep inside the grinding zone. Conventional method of fluid delivery system is not capable of penetrating this stiff air layer, and thus cannot control grinding temperature and thermal defects effectively. In this work, formation of stiff air layer has been studied experimentally by measuring the variation of air pressure around grinding wheel periphery at different conditions. A pneumatic barrier setup has been developed first time for restricting the stiff air layer around grinding wheel. It is found from analysis of variance (ANOVA) that both pneumatic barrier position and orientation have significant effects on suppressing air layer pressure around the grinding wheel. Using the pneumatic barrier, reduction of air pressure up to 53% has been observed experimentally. Hence, it reduces wastage of grinding fluid, leading to less environmental problem. Surface grinding experiments using the pneumatic barrier setup shows remarkable reduction in forces and surface roughness over flood cooling conditions expectedly due to better penetration of fluid in the grinding zone, showing its applicability.
The phototransformations of tricyclic β, γ-enones with substitutions on the π bond (10a–10c) have... more The phototransformations of tricyclic β, γ-enones with substitutions on the π bond (10a–10c) have been studied. All of them were found to yield only the corresponding oxa-di-π-methane-rearranged products 11a–11c on direct as well as on sensitized irradiation. Quenching studies suggest that states other than the lowest triplet are involved in the cases of 10a and 10b.
Livistona chinensis is used as an anticancer agent in traditional Chinese medicine. In vitro, the... more Livistona chinensis is used as an anticancer agent in traditional Chinese medicine. In vitro, the extracts of fruits and seeds of L. chinensis are known to possess antiangiogenic and antiproliferative activities. Here we report the presence of phenolic compounds in L. chinensis fruits which show hemolytic activity. The hemolytic activity of phenolics is limited to an acid-precipitable fraction. Further, presence of proteins and lipids abrogated the hemolytic activity indicating astringent and membrane damaging activities as mechanisms of hemolysis. In conclusion, the hemolytic activity of phenolics in L. chinensis fruits is due to astringent and membrane damaging activities.
A Lead salt midinfrared quantum-well (QW) laser on [110] orientation is proposed. Theoretical sim... more A Lead salt midinfrared quantum-well (QW) laser on [110] orientation is proposed. Theoretical simulations of [110] QW edge-emitting lasers show a 70° temperature increase in continuous-wave operation compared to the conventional [100]-orientated lasers. This is because the gain on [100]-orientated QW structure is significantly increased. Among [100], [111], and [110] orientations, [110]-orientated QW structure offers the highest gain. PbSe/PbSrSe QW structures were successfully grown on [110]-orientated BaF2 substrate by molecular-beam-epitaxy (MBE). Photoluminescence intensity of [110]-orientated samples was twice as high as that on [111]-orientated BaF2 substrates from the same MBE run.
PbSe thin film and PbSe/PbSrSe multiple quantum well (MQW) structures were successfully grown on ... more PbSe thin film and PbSe/PbSrSe multiple quantum well (MQW) structures were successfully grown on (1 1 0) BaF 2 substrates by molecular beam epitaxy. The average linewidth of the rocking curve from high-resolution X-ray diffraction measurements of the (2 2 0) reflection for the PbSe thin film was 60 arcsec, which indicates high crystalline quality. The dislocation density estimated from the rocking curve was 1 Â 10 7 cm À2 . Strong photoluminescence (PL) of the MQW structure at room temperature was observed. This PL signal was two times larger than those measured from a duplicate structure grown at the same time on a (1 1 1) BaF 2 substrate. The energy bandgap of (1 1 0) PbSe follows the same temperature dependence as [1 0 0]-and [1 1 1]-orientated PbSe. r
Abstract: The effect of plant growth regulators on callus induction using different explants, to ... more Abstract: The effect of plant growth regulators on callus induction using different explants, to regenerate shoot/root from different explants as well as from calli in cultures of Catharanthus roseus (L.) G. Don was studied. Total of nineteen shoot regeneration media were used, ...
ABSTRACT Assessment of soil organic C (SOC) stocks is important for monitoring the effect of land... more ABSTRACT Assessment of soil organic C (SOC) stocks is important for monitoring the effect of land use change in the C cycle and for formulation of C sequestration strategies in the context of global climate change. Discrepancies among the recent global SOC estimates by different researchers underscore the importance of precise estimation of the uncertainty associated with the SOC stocks. A method was recently proposed to estimate the SOC storage uncertainty using the Taylor series of approximations. Here we show that the accuracy of SOC storage uncertainty can be improved by incorporating the covariance among the input variables. Measurement of input variables from independent samples or use of an incomplete model leads to either over-or underestimation of the SOC storage uncertainty. The application of the method to an experimental data set indicated that ignoring covariance would lead to a substantial overestimate of the uncertainty.
| Infertile men are frequently affected by physical abnormalities that might be detected on routi... more | Infertile men are frequently affected by physical abnormalities that might be detected on routine general and genital examinations. These structural abnormalities might damage or block the testes, epididymis, seminal ducts or other reproductive structures and can ultimately decrease fertility. Physical deformities are variable in their pathological impact on male reproductive function; some render men totally sterile, such as bilateral absence of the vasa deferentia, while others cause only mild alterations in semen parameters. Concise and up-to-date information regarding the contemporary epidemiological characteristics, clinical features and pathophysiological impacts of these common abnormalities on male fertility is crucial for the practicing urologist to identify the best treatment option.
Isolated esophageal tuberculosis is very rare. We report a patient who presented with history of ... more Isolated esophageal tuberculosis is very rare. We report a patient who presented with history of retrosternal pain and dysphagia and on investigation was found to have a smooth esophageal mass. Endoscopic biopsy showed epitheloid cell granuloma with necrosis suggestive of tuberculosis. CT scan of the thorax showed no involvement of adjacent structures. The patient responded to antitubercular therapy.
Efficacy of doramectin administered via oral and parenteral routes against experimentally induced... more Efficacy of doramectin administered via oral and parenteral routes against experimentally induced and natural infections of the copepod parasite Lernaea cyprinacea in carps was studied. Administration of doramectin incorporated in feed at 1 mg/kg b.wt. of fish for 10 days effectively controlled experimentally induced Lernaea infection in Labeo fimbriatus fingerlings within an average of 19 days of post-treatment as compared to the normal course of 41 days. Similarly, doramectin given through feed at 1 mg/kg b.wt. of fish for 10 days was equally effective in controlling natural infection of this parasite in the underyearlings of Catla catla and L. fimbriatus. Intramuscular administration of doramectin at 200 mg/kg b.wt. of fish effectively removed adult Lernaea infection in L. fimbriatus as early as 18 days of treatment as compared to the time period of 43 days taken by the untreated fish to get rid of the infection. Single intramuscular administration of the drug was more effective against the parasite than its administration in multiple divided doses. In all cases, doramectin did not cause any noticeable adverse reactions or toxicity to the fish host. In view of the handling associated stress and other operational difficulties involved, a single intramuscular administration of the drug at 200 mg/ kg b.wt. is suggested for treatment of heavily infected adults and brood stock of carps. Doramectin incorporated in feed at 1 mg/ kg b.wt. of fish is best suited for treatment of Lernaea infection in young fish including fingerlings. However, detailed studies on the toxicity and pharmacokinetics of doramectin upon its administration to aquatic organisms and the environmental impact of its usage are required to be undertaken before finally recommending the safe use of this drug for control of parasitic infections of aquatic organisms. #
Thyroid hormones, previously thought not to affect spermatogenesis and male fertility, are now be... more Thyroid hormones, previously thought not to affect spermatogenesis and male fertility, are now being recognized as having important role in spermatogenesis. The identification of thyroid hormone receptors on Sertoli cells, the nurturing cells for sperm in the testis, has embarked further research to investigate the role of thyroid hormones in male reproduction. Since spermatogenesis occurs in close contact with the Sertoli cells, the thyroid hormones must exert significant regulatory role in sperm production. Therefore, disturbances in the thyroid function could affect spermatogenesis and male fertility. Studies on human subjects and animals models are now revealing further insights into the effect of thyroid hormones on male fertility and infertility. The present review provides an update on the role of thyroid hormones in spermatogenesis and male fertility.
Stress produces definable mental and physiological reactions in the body. Mild stress is benefici... more Stress produces definable mental and physiological reactions in the body. Mild stress is beneficial in cognitive tasks and performance but persistently high stress may lead to neuropsychiatric illnesses like anxiety and depression. Examinations act as stressor and activate hypothalamicpituitary adrenal axis causing an increase in cortisol level, which is reflected in saliva. Present study was done on 35 medical students. Their mood parameters were assessed, using Depression Anxiety Stress Scale (DASS) scoring, and salivary cortisol levels using quantitative ELISA. Subjects were evaluated for mood parameters two times, one during relaxed state (with no examinations in preceding 2 weeks and in coming 2 weeks) and another during stressed state (on the day of viva voce examination). The levels of mood parameters and salivary cortisol were significantly raised during examination stress. The changes in stress level significantly correlated with change in levels of anxiety and salivary cortisol though there was no significant effect on the performance. Males and females showed similar changes in mood parameters. This study suggests that as examinations act as unavoidable stressors, the medical educators as well as students should be made aware of the negative consequences of stress faced during medical training. Efficient relaxation program as well as counseling services should be provided to stressed students so that they are able to cope better with examination stress.
In grinding process, a stiff air layer is generated around the wheel due to rotation of porous gr... more In grinding process, a stiff air layer is generated around the wheel due to rotation of porous grinding wheel at high speed. This stiff air layer restricts fluid to reach deep inside the grinding zone. Conventional method of fluid delivery system is not capable of penetrating this stiff air layer, and thus cannot control grinding temperature and thermal defects effectively. In this work, formation of stiff air layer has been studied experimentally by measuring the variation of air pressure around grinding wheel periphery at different conditions. A pneumatic barrier setup has been developed first time for restricting the stiff air layer around grinding wheel. It is found from analysis of variance (ANOVA) that both pneumatic barrier position and orientation have significant effects on suppressing air layer pressure around the grinding wheel. Using the pneumatic barrier, reduction of air pressure up to 53% has been observed experimentally. Hence, it reduces wastage of grinding fluid, leading to less environmental problem. Surface grinding experiments using the pneumatic barrier setup shows remarkable reduction in forces and surface roughness over flood cooling conditions expectedly due to better penetration of fluid in the grinding zone, showing its applicability.
The phototransformations of tricyclic β, γ-enones with substitutions on the π bond (10a–10c) have... more The phototransformations of tricyclic β, γ-enones with substitutions on the π bond (10a–10c) have been studied. All of them were found to yield only the corresponding oxa-di-π-methane-rearranged products 11a–11c on direct as well as on sensitized irradiation. Quenching studies suggest that states other than the lowest triplet are involved in the cases of 10a and 10b.
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Papers by Rahul Singh