Browsing by Author "Alka Singh"

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A stewardship of ramgarh lake in gorakhpur district: Uses, problems and management
(Institute of Indian Geographers, 2018) Alka Singh; V.N. Sharma
Water is essential for sustaining life and at the same time, it is an important component for almost all developmental plans, however, Growing population, urbanization and industrialization has led to considerable increase in demand of water for various purposes. The present work is focused on uses, deteriorating factors and suggestion for restoration of Ramgarh Lake. Ramgarh Lake (26º42′30′′N - 26º45′N & 83º24′20′′E- 83º25′20′′), covering an area of 576 hectare which is situated in the center of Gorakhpur district and this district exist in the north-eastern part of Uttar Pradesh. Large populations depend on this water body for fish, vegetable, water, irrigation, waste disposal site, washing site and recreational activity. Dumping of solid as well as liqid wastes has resulted in the uncontrolled growth of aquatic weeds, eutrophication and sedimentation, which have altered lake’s morphology, volume, depth and quality of water .Importance of lakes understood by the people and therefore serious measures are being taken towards the stewardships of water bodies. Ramgarh lake also being neglected in past, but now, this conservation of lake is estimated to ensure the better future of Gorakhpur city. © 2018 Institute of Indian Geographers. All rights reserved.
Analysis of morphological change of lentic water bodies by using spatial vulnerability index (SVI) in Tarai region of Rapti river plains, India
(Taylor and Francis Ltd., 2024) Alka Singh; Vishwambhar Nath Sharma; Narendra Kumar Rana
Spatio-temporal analysis of waterbodies in terms of detection of morphological change could serve as a guiding tool to restore the lentic ecosystem. This research analysed the loss of lake extent within 50 years (1969–2019) through natural, anthropogenic reasons, as well as a lack of attention to protecting lakes in the Tarai region. In 1969, 75 lakes were found, but now only 46 lakes are alive. Among the 75 lakes, seventeen transformed into large ponds after reduction in extent, and twelve lakes either appeared as waterlogging zones during the rainy season or were permanently extinct and used as agricultural fields’ built-up activities. The spatial vulnerability index (SVI) measured the level of deterioration and urgency of lake restoration. 8 lakes were determined to be highly vulnerable (below 29.26%) and lost about 311.20 hectares of potential area of lake beds due to gradual increasing shallowness. Regression analysis measured a very weak correlation between the reducing percent of lake extent (during 50 years) and current lake extent (R2 = 0.1336), average depth (R2 = 0.0035), circumference (R2 = 0.0543), and volume (R2 = 0.0728) of 46 lakes. This study elucidated the restoration practices of the lakes to prevent their gradual extinction. © 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of the International Water, Air & Soil Conservation Society(INWASCON).
Analysis of morphological change of lentic water bodies by using spatial vulnerability index (SVI) in Tarai region of Rapti river plains, India
(Taylor and Francis Ltd., 2025) Alka Singh; Vishwambhar Nath Sharma; Narendra Kumar Rana
Spatio-temporal analysis of waterbodies in terms of detection of morphological change could serve as a guiding tool to restore the lentic ecosystem. This research analysed the loss of lake extent within 50 years (1969–2019) through natural, anthropogenic reasons, as well as a lack of attention to protecting lakes in the Tarai region. In 1969, 75 lakes were found, but now only 46 lakes are alive. Among the 75 lakes, seventeen transformed into large ponds after reduction in extent, and twelve lakes either appeared as waterlogging zones during the rainy season or were permanently extinct and used as agricultural fields’ built-up activities. The spatial vulnerability index (SVI) measured the level of deterioration and urgency of lake restoration. 8 lakes were determined to be highly vulnerable (below 29.26%) and lost about 311.20 hectares of potential area of lake beds due to gradual increasing shallowness. Regression analysis measured a very weak correlation between the reducing percent of lake extent (during 50 years) and current lake extent (R2 = 0.1336), average depth (R2 = 0.0035), circumference (R2 = 0.0543), and volume (R2 = 0.0728) of 46 lakes. This study elucidated the restoration practices of the lakes to prevent their gradual extinction. © 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of the International Water, Air & Soil Conservation Society(INWASCON).
Anchoring CuO nanoparticle on nitrogen-doped reduced graphene oxide as nanocatalyst for the synthesis of 5-substituted-1H-tetrazole and 1,2,3- triazole derivatives
(Elsevier B.V., 2023) Alka Singh; Alka Agarwal
A basic and proficient newer method was exploited for the preparation of CuO-NrGO nanoparticles which was characterized by state of art instruments i.e. Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), Energy dispersive X-ray (EDX), Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), Thermo gravimetric analysis (TGA) and UV-visible spectroscopy. The prepared heterogeneous nanoparticle possesses a significant level of catalytic activity for the production of two diversified series i.e.5-substituted-1H-tetrazole and 1,2,3-triazole derivatives in excellent yield (92% and 95% respectively) with minimal catalyst loading. CuO-NrGO nanoparticles showed reusability up to seven repetitions without any significant loss (11% in 5-substituted-1H-tetrazole and 10.3% in 1,2,3-triazole derivatives) of catalytic activity and productivity. © 2023 Elsevier B.V.
Auxin signaling modulates LATERAL ROOT PRIMORDIUM1 (LRP1) expression during lateral root development in Arabidopsis
(Blackwell Publishing Ltd, 2020) Sharmila Singh; Sandeep Yadav; Alka Singh; Mahima Mahima; Archita Singh; Vibhav Gautam; Ananda K. Sarkar
Auxin signaling mediated by various auxin/indole-3-acetic acid (Aux/IAAs) and AUXIN RESPONSE FACTORs (ARFs) regulate lateral root (LR) development by controlling the expression of downstream genes. LATERAL ROOT PRIMORDIUM1 (LRP1), a member of the SHORT INTERNODES/STYLISH (SHI/STY) family, was identified as an auxin-inducible gene. The precise developmental role and molecular regulation of LRP1 in root development remain to be understood. Here we show that LRP1 is expressed in all stages of LR development, besides the primary root. The expression of LRP1 is regulated by histone deacetylation in an auxin-dependent manner. Our genetic interaction studies showed that LRP1 acts downstream of auxin responsive Aux/IAAs-ARFs modules during LR development. We showed that auxin-mediated induction of LRP1 is lost in emerging LRs of slr-1 and arf7arf19 mutants roots. NPA treatment studies showed that LRP1 acts after LR founder cell specification and asymmetric division during LR development. Overexpression of LRP1 (LRP1 OE) showed an increased number of LR primordia (LRP) at stages I, IV and V, resulting in reduced emerged LR density, which suggests that it is involved in LRP development. Interestingly, LRP1-induced expression of YUC4, which is involved in auxin biosynthesis, contributes to the increased accumulation of endogenous auxin in LRP1 OE roots. LRP1 interacts with SHI, STY1, SRS3, SRS6 and SRS7 proteins of the SHI/STY family, indicating their possible redundant role during root development. Our results suggested that auxin and histone deacetylation affect LRP1 expression and it acts downstream of LR forming auxin response modules to negatively regulate LRP development by modulating auxin homeostasis in Arabidopsis thaliana. © 2019 The Authors The Plant Journal © 2019 John Wiley & Sons Ltd
Ciprofloxacin-Tethered 1,2,3-Triazole Conjugates: New Quinolone Family Compounds to Upgrade Our Antiquated Approach against Bacterial Infections
(American Chemical Society, 2022) Alka Agarwal; Preeti Singh; Anand Maurya; Upendra Kumar Patel; Alka Singh; Gopal Nath
A newer ciprofloxacin series containing 1,2,3-triazole conjugates of ciprofloxacin was designed, synthesized, and well characterized using modern analytical techniques by reacting diversified anilines with ciprofloxacin obtained from ciprofloxacin hydrochloride. The newer conjugates were evaluated for their antimicrobial activity against various strains, viz. Staphylococcus aureus (ATCC25923), Enterococcus faecalis (clinical isolate), Staphylococcus epidermidis (ATCC3594), Escherichia coli (ATCC25922), Pseudomonas aeruginosa (ATCC27853), Salmonella typhi (clinical isolate), Salmonella typhimurium (clinical isolate), Acinetobacter baumannii (ATCC19606), Aeromonas hydrophila (ATCC7966), Plesiomonas shigelloides (ATCC14029), and Sphingo biumpaucimobilis (MTCC6362) in vitro. Interestingly, some of the conjugates showed superior antimicrobial activity as compared to the control drug ciprofloxacin. The three compounds 4i, 4j, and 4n showed strong activity with minimum inhibitory concentration (MIC) 0.78 μM, while the compound 4g showed MIC 1.56 μM against S. typhi (clinical). The compound 4a showed good efficacy against S. aureus (ATCC25923) and S. typhi (clinical) with MIC 3.12 μM, while the compound 4b exhibited efficacy with MIC 3.12 μM against S. aureus (ATCC25923) and the control drug ciprofloxacin showed MIC 6.25 μM. Among all of the synthesized compounds, 4e, 4f, 4g, 4h, 4p, 4q, 4t, and 4u displayed less than 20% hemolysis, while the rest of the compounds showed hemolysis in the range of 21–48%. Moreover, the structure of compound 4b was also established by single-crystal X-ray diffraction studies. © 2022 The Authors. Published by American Chemical Society
Combination of DEC plus aspirin induced mitochondrial mediated apoptosis in filarial parasite Setaria cervi
(2010) Alka Singh; Sushma Rathaur
Diethylcarbamazine (DEC) is the main drug used against lymphatic filariasis but it is only microfilaricidal. Hence there is an urgent need for adulticidal drug. Aspirin is known nonsteroidal anti-inflammatory drugs which can inhibit prostaglandin H synthase and also induces apoptosis. Studies presented in this paper demonstrated that exposure of worms to the combination of DEC plus aspirin (DEC + A) at 100 μM concentration irreversibly paralyzed adult worms as well as microfilariae within 2 h. Some of the apoptosis markers viz; DNA fragmentation with accompanying ladder formation, upregulation of Bax expression and decrease in Bcl-2 have suggested that the parasite may be killed due to mitochondrial mediated apoptosis. The levels of several apoptosis regulating proteins and enzymes have also shown to be altered. DEC + A treated worms showed significant decrease in prostaglandin H synthase activity (PGHS) and increase in the level of nitric oxide (NO) and cysteine proteases while glutathione (GSH) and peroxidase level was found to be decreased. NO is known inducer of mitochondrial mediated apoptosis and acts by increasing the permeability of mitochondrial membrane through Bax and allowing cytochrome c to release in cytosol, inducing caspases leading to apoptosis. The DEC + A concentration used in this study is much lower than recommended dose so its intake is safe. Here we report for the first time that combination of DEC and aspirin is more effective and could be used as an adulticidal for control of human filarial infections. © 2010 Elsevier Masson SAS.
Comparative Evaluation of the Effect of Laser Therapy and Behavioral Counseling in Tobacco Cessation: A Randomized Controlled Trial
(Kerman University of Medical Sciences, 2025) Zainab Akram; Puvvadi G. Naveen Kumar; Mahesh R. Khairnar; Jadhav Sachin Kumar; Jyotsna Kailashiya; S. Savitha Priyadarsini; Alka Singh
Background: Laser auricular acupuncture is a form of therapy that is non-invasive, aseptic, and painless, thus advantageous over the traditional form of acupuncture for tobacco cessation. The objective of the study is to evaluate and compare nicotine dependence, urinary cotinine level, physical effects, and quit rate among tobacco chewers before and one month after laser therapy and behavioral counseling, and to evaluate and compare extrinsic stains one month post-intervention. Methods: The present study was a randomized controlled trial, with laser therapy and behavioral counseling as the test and control interventions, respectively. The laser was focused on both ears once a week for four weeks. Counseling sessions were held once a week for four weeks. Nicotine dependence, urinary cotinine level, physical effects, as measured using the Visual Analog Scale, and quit rate were recorded before and after the intervention. Results: The results showed significant reductions in nicotine dependence in both laser and counseling groups post-intervention (P < 0.001). Urinary cotinine levels increased significantly in the counseling group post-intervention (P = 0.010). Inter-group comparison revealed significant differences in pre-and post-intervention cotinine levels (P < 0.05). Adjusted analysis confirmed significant post-intervention differences between the groups (P = 0.048). Conclusion: This study demonstrates that combining laser auricular acupuncture therapy with behavioral counseling yields superior outcomes for smokeless tobacco cessation compared to behavioral counseling alone. The combined approach results in greater reductions in nicotine dependence, lower urinary cotinine levels, slightly higher quit rates, and significant improvements in various physical effects associated with tobacco use. © 2025 The Author(s); Published by Kerman University of Medical Sciences.
Comparison of Platelet Functions, Plasma Proteins and Lipids in Filarial and Non-Filarial Edema Patients
(John Wiley and Sons Inc, 2025) Sushil Surtani; Ashutosh Kumar; Alka Singh; Mumtaz Ahmad Ansari; Jyotsna Kailashiya
Lymphatic filariasis results in chronic edema, pain, elephantiasis and disfigurement in humans. It was previously reported that platelet aggregation is inhibited in lymphatic filariasis patients, compared to healthy controls. However, it was not clear whether the inhibition was due to filarial parasite infection or due to the presence of edema. This study was planned to compare platelet functions, plasma proteins and lipids in filarial and non-filarial edema patients. Edema patients were tested for the presence of filarial antigens and antibodies in their blood and were grouped as filarial and non-filarial edema patients accordingly. Platelet aggregation, size distribution, platelet activation markers, plasma proteins and lipids were measured in collected blood samples. Results showed that platelet aggregation was significantly inhibited in filarial edema patients, compared to non-filarial edema patients. Soluble P-selectin and beta thromboglobulin showed significant positive correlation with each other only in non-filarial edema patients. Plasma total cholesterol was lower in filarial edema patients, and HDL was lower in only female filarial edema patients. Observations confirm that inhibition of platelet functions is due to filarial parasite infection, not merely due to the presence of edema. Results also indicate uncoupling and disturbances of platelet activation processes. © 2025 John Wiley & Sons Ltd.
Development of a multiplex MethyLight assay for he detection of DAPK1 and SOX1 methylation in epithelial ovarian cancer in a north Indian population
(2016) Manpreet Kaur; Alka Singh; Manisha Sachan; Kiran Singh; Sameer Gupta
Ovarian cancer is the fourth most common cancer in women worldwide. It is very heterogeneous at the clinical, histopathological and molecular levels and is caused by the accumulation of genetic and epigenetic changes in regulatory genes. More than 90% of ovarian cancers are epithelial in origin. Ovarian cancer is typically asymptomatic in its early stages, and due to difficulties in early detection, most ovarian cancers are diagnosed at an advanced stage. The positive predictive value of CA-125, a routinely used serum protein marker is < 30%; therefore, for effective screening, there is a need to develop a marker with high sensitivity for early detection. Development of blood-based biomarkers that detect DNA methylation in cellfree tumor-specific DNA is now being considered as a potential approach for the early diagnosis of cancer. Our objective in this study was to develop an absolute quantitative method, the MethyLight assay, to detect the promoter methylation status of two tumor suppressor genes. We analyzed the methylation level of the promoter regions of these genes in 42 tumor samples using the MethyLight assay. SOX1 promoter methylation was significantly higher in cancer samples than in normal samples (P = 0.011), whereas this difference between cancer and normal samples was not significant for DAPK1 promoter methylation (P = 0.18), when analyzed separately in a singleplex assay, whereas the detection frequency and significance level increased several-fold when these genes were analyzed together in a multiplex assay (P = 0.0004).The sensitivity was found to be 62% and 83% for DAPK1 and SOX1, respectively, when analyzed separately in the singleplex assay, but increased to 90% in the multiplex assay when either the SOX1 or the DAPK1 gene promoters showed methylation. © 2016, The Genetics Society of Japan. All rights reserved.
Effect of diethylcarbamazine, butylated hydroxy anisole and methyl substituted chalcone on filarial parasite Setaria cervi: Proteomic and biochemical approaches
(2011) Sushma Rathaur; Marshleen Yadav; Neetu Singh; Alka Singh
For survival, parasite exerts several lines of defense of which drug neutralization is one of the major phenomena. Lack of phase I cytochrome P450 in some of the nematode render them depend on the phase II detoxification system involving GST as a major detoxifying enzymes. In present study, the antifilarial DEC, phenolic compound BHA and methyl chalcone have been evaluated for proteomic and biochemical studies in Setaria cervi. BHA and methyl chalcone showed cytotoxic effect leading to irreversible inhibition in motility and viability of parasites. These drugs showed marked alteration in proteomic profile of S. cervi at 100 μM concentration with 10.82, 8.52 and 6.75% downregulated (< 0.5) and 7.64, 31.78 and 24.32% upregulated (> 1.5) in DEC, BHA and methyl chalcone treatment respectively. Significant depletion in GSH level with increase in NO production was observed. Amongst these compounds, methyl chalcone demonstrated significant inhibitory effect (p < 0.05) on GST, PGHS and PTP activity leading to loss of metabolic homeostasis and parasite death. The cytotoxic response and altered expression profile of major enzymes under drug exposure suggested the oxidative stress induced apoptosis as a major cause of parasite killing which was further supported by DNA fragmentation in BHA and methyl chalcone. © 2011 Elsevier B.V.
Evidence for the presence of prostaglandin H synthase like enzyme in female Setaria cervi and its inhibition by diethylcarbamazine
(2009) Sushma Rathaur; Alka Singh; Marshleen Yadav; Reeta Rai
Experimental evidence has shown that Setaria cervi a bovine filarial parasite contains significant amount of prostaglandin H synthase like activity in the somatic extract of its different life stages. A protein with characteristics of prostaglandin H synthase was purified to homogeneity from female somatic extract using a combination of affinity and gel filtration chromatography. Molecular weight of purified enzyme was 70 kDa as determined by SDS-PAGE. Purified enzyme showed high activity with arachidonic acid and TMPD substrates suggests the presence of both cyclooxygenase and peroxidase activity in enzyme. Fluorescence spectroscopy and hemin-associated peroxidase activity confirmed presence of heme in purified enzyme. The Km and Vmax values using arachidonic acid were determined to be 79 ± 1.5 μM and 0.165 ± 0.2 U/ml, respectively. Further, indomethacin and aspirin, specific inhibitors for PGHS, significantly inhibited the enzyme activity. Diethylcarbamazine, an antifilarial drug inhibited the microfilarial PGHS like activity as well as their motility. Here we are reporting for the first time PGHS like activity in filarial parasite and its inhibition with DEC which provide that this enzyme could be used as a drug target. © 2009 Elsevier B.V. All rights reserved.
Impact of herbicide and various soil amendments on soil enzymes activities in a tropical rainfed agroecosystem
(2013) Alka Singh; Nandita Ghoshal
A two year study was designed to investigate the activities of soil enzymes namely β-glucosidase, alkaline phosphatase and urease in an agroecosystem under rice-wheat-summer fallow crop rotation receiving herbicide (HC) as Butachlor, either singly or in combination of soil amendments of varying resource quality. Chemical fertilizer (CF), Sesbania shoot (SS), farmyard manure (FYM) and wheat straw (WS), carrying equivalent amount of N were added in combination of HC to soil along with a no input control (CO). Throughout the annual cycle, the activity of β-glucosidase was maximum in HC + WS treatment followed by the decreasing order for HC + FYM > HC + SS > HC + CF > HC > CO plots. Almost similar trend was found for alkaline phosphatase activity throughout the annual cycle. Within the crop cycle, the activities of the two enzymes increased from the vegetative to grain forming stage and then decreased at crop maturity. By contrast, urease activity decreased constantly through the crop cycle for all the treatments except the HC + WS treatment. The interaction of herbicide with soil inputs irrespective of their resource quality compared to single application of herbicide increased activities of all the three enzymes throughout the annual cycle. The activity of β-glucosidase, alkaline phosphatase and urease was influenced by the C:N ratio of the various soil inputs. © 2012 Elsevier Masson SAS.
Microbial Biomass Dynamics in a Tropical Agroecosystem: Influence of Herbicide and Soil Amendments
(Institute of Soil Science, 2016) Alka Singh; Mahesh Kumar Singh; Nandita Ghoshal
The influences of herbicide alone and in combination with the soil amendments with contrasting resource qualities on dynamics of soil microbial biomass C (MBC), N (MBN), and P (MBP) were studied through two annual cycles in rice-wheat-summer fallow crop sequence in a tropical dryland agroecosystem. The experiment included application of herbicide (butachlor) alone or in combination with various soil amendments having equivalent amount of N in the forms of chemical fertilizer, wheat straw, Sesbania aculeata, and farm yard manure (FYM). Soil microbial biomass showed distinct temporal variations in both crop cycles, decreased from vegetative to grain-forming stage, and then increased to maximum at crop maturity stage. Soil MBC was the highest in herbicide + Sesbania aculeata treatment followed by herbicide + FYM, herbicide + wheat straw, herbicide + chemical fertilizer, and herbicide alone treatments in decreasing order during the rice-growing period. During wheat-growing period and summer fallow, soil MBC attained maximum for herbicide + wheat straw treatment whereas herbicide + FYM, herbicide + Sesbania, and herbicide + chemical fertilizer treatments showed similar levels. The overall trend of soil MBN was similar to those of soil MBC and MBP except that soil MBN was higher in herbicide + chemical fertilizer treatment over the herbicide + wheat straw treatment during rice-growing period. In spite of the addition of equivalent amount of N through exogenous soil amendments in combination with the herbicide, soil microbial biomass responded differentially to the treatments. The resource quality of the amendments had more pronounced impact on the dynamics of soil microbial biomass, which may have implications for long-term sustainability of rainfed agroecosystems in dry tropics. © 2016 Soil Science Society of China.
Short report: antifilarial activity of 1,3-diarylpropen-1-one: effect on glutathione-s-transferase, a phase ii detoxification enzyme
(American Society of Tropical Medicine and Hygiene, 2009) Satish K. Awasthi; Nidhi Mishra; Sandeep Kumar Dixit; Alka Singh; Marshleen Yadav; Sudhanshu S. Yadav; Sushma Rathaur
Chalcone derivatives were evaluated for their antifilarial activity on Setaria cervi using glutathione-s-transferase (GST) as a drug target. The compounds 1-(4-benzotriazol-1-yl-phenyl)-3-(4-methoxyphenyl)prop-2-en-1-one (5), and 3-(4-methoxyphenyl)-1-(4-pyrrolidin-1-yl-phenyl) prop-2-en-1-one (7) showed a significant suppression (P < 0.01) in GST activity of adult female parasite extract at 3 μM concentration in vitro. However, GST activity was detected along with depletion in GSH level. Except Compounds 1 and 2, all exhibited a significant effect on the motility and viability of adult parasites. Compounds 3-(4-chlorophenyl)-1-(4-piperidin-1-yl-phenyl)prop-2-en-1-one (3), 1-4-ben-zotriazol-1-yl-phenyl)-3-(4-methoxyphenyl)prop-2-en-1-one (5), and 3-(4-methoxyphenyl)-1-(4-pyrrolidin-1-yl-phenyl) prop-2-en-1-one (7) exhibited major irreversible effects on viability and resulted in parasite death and also inhibited the GST activity by 84-100% in vitro. We report for the first time the antifilarial activity of chalcones on GST of adult para-sites. This study also strengthens our previous findings where GST is reported as a potential drug target for antifilarials. Copyright © 2009 by The American Society of Tropical Medicine and Hygiene.
Soil physicochemical properties in a grassland and agroecosystem receiving varying organic inputs
(2009) Sonu Singh; Ritu Mishra; Alka Singh; Nandita Ghoshal; K.P. Singh
The application of organic amendments in agroecosystems has been widely recommended, but the impact of their C/N ratio on the stabilization and sequestration of soil organic carbon (SOC) is often unaccounted for. The influence of the C/N ratio of amendments on soil physicochemical properties in a rice (Oryza sativa var. NDR97)-barley [Hordeum vulgare var. Lakhan) rotation tropical dryland agroecosystem was compared with an undisturbed grassland. Chemical fertilizer in the form of urea and three organic inputs (Sesbania aculeata shoot, low C/N ratio; air-dried straw of wheat [Triticum aestivum var. Malviya 533), high C/N ratio; and S. aculeata shoot+wheat straw, high and low C/N ratio combined) carrying an equivalent amount of N, were added to plots of the agroecosystem once during each annual cycle. Soil water-holding capacity (WHC), porosity, SOC, total N, and aggregate stability were improved in the wheat straw and S. aculeata shoot+wheat straw treatments, reaching levels comparable with the grassland. Soil WHC, porosity, and SOC influenced the productivity of the grassland and the agroecosystem. The grassland recorded highest SOC (53% higher relative to control) followed by the wheat straw (+47%), S. aculeata shoot+wheat straw (+37%) and soil total N was greatest in the S. aculeata shoot+wheat straw treatment (+37.5%). Aggregate stability and macroaggregate distribution were also higher in the wheat straw and S. aculeata shoot+wheat straw treatments, however, the microaggregate and silt + clay fractions showed a reverse trend. Management practices with a higher residue-C return in the agroecosystem resulted in increased aggregate stability and aggregate-associated SOC, with C storage attaining levels similar to the natural system. © Soil Science Society of America.
Structural modeling and simulation studies of Brugia malayi glutathione-S-transferase with compounds exhibiting antifilarial activity: Implications in drug targeting and designing
(2010) Marshleen Yadav; Alka Singh; Sushma Rathaur; Eva Liebau
Since glutathione-S-transferase (GST) mediated xenobiotic detoxification is a crucial mechanism in nematodes survival, we aimed to conduct an in silico analysis of filarial GST in order to predict the possible interactions for antifilarials. Present report depicts the homology modeling approach applied in the construction of molecular structure of Brugia malayi GST (BmGST) followed by its docking simulation with available antifilarials such as diethylcarbamazine, albendazole, Butylated Hydroxyanisole (BHA) and substituted chalcones. A very low root mean square deviation (0.82 Å) from template structure and stereochemical quality of constructed BmGST model proposed it as a significant framework for further analysis. In docking studies antifilarials and chalcones exhibited demarcation in their binding affinity and modes. Amongst all the compounds studied, albendazole and methyl-substituted chalcone showed the lowest binding energy and occupied binding pocket near to substrate binding site of GST. The side chain of these compounds interplayed as a potential interaction site which targeted mainly hydrophilic residues of the BmGST. The structural information and binding site mapping of BmGST for different antifilarials obtained from this study could aid in screening and designing new antifilarials or selective inhibitors for chemotherapy against filariasis. © 2009 Elsevier Inc. All rights reserved.
Sustainability in agroecosystems: Management strategies involving herbicides and organic inputs
(Nova Science Publishers, Inc., 2018) Mahesh Kumar Singh; Biswadip Mukherjee; Chandra Mohan Kumar; Alka Singh; Nandita Ghoshal
Long-term sustainable management of agroecosystems has now become a global challenge, along with the major objective of maximizing the crop yield. This has led to the switching of research focus, from ‘high input and maximum yields’ to ‘low input and high efficiency sustainable agriculture’. Such approaches have generated renewed and wide interest in ecological aspects of crop production and sustainable agriculture. Organic inputs, rather than the chemical fertilizers are now considered to have the potential to conserve the soil fertility, in terms of a greater soil C storage, the soil microbial biomass, and the crop productivity in the tropical dryland rainfed agroecosystems, especially in the dry tropics of the Indian subcontinent. Weed infestation is a severe problem in agroecosystems, especially in rainfed croplands, as compared to the irrigated systems. The application of herbicide is a common method to control the weeds. Since the continuous and extensive use of herbicides may differently affect the soil organic matter dynamics, therefore, concerns are raised for the long-term sustainability of agroecosystems. The application of high-quality organic resources along with herbicide, not only negates the harmful side effects of these farm-chemicals, but also benefitted the first crop, in terms of improving the soil microbial biomass, the soil carbon sequestration potential, the soil N balance, and the total crop productivity, whereas these benefits were observed in the subsequent crop, when low quality inputs were added along with the herbicides. The combined application of herbicides with the organic inputs of contrasting resource qualities may thus help in, not only sustaining the long-term soil fertility and productivity, but also, in mitigating the increased atmospheric carbon dioxide concentration through its sequestration in agroecosystem soils. © 2018 Nova Science Publishers, Inc.
Treatment of maxillary lateral incisor-canine pseudotransposition: A case report
(IP Innovative Publication Pvt. Ltd., 2022) T.P. Chaturevdi; Vipul Kumar Sharma; Alka Singh
The term transposition is used to refer to an interchange in the position of 2 adjacent teeth within the same quadrant of the dental arch.In complete transposition, both the crowns and the entire root structures of the involved teeth are found parallel in their transposed positions. In incomplete transposition (also called “pseudo” or “partial” transposition) the crowns may be transposed while the root apices remain in their normal positions. Unilateral transposition has been reported more often than bilateral transposition, with the left side being somewhat more frequently involved than the right side. The only dental anomaly that has an apparent association with maxillary canine-lateral incisor transposition is increased third molar agenesis.Treatment of maxillary canine-lateral incisor transposition depends on many factors like the condition of the root of central incisors, shape of lateral incisors, need of extraction because of either severe crowding or profile improvement, etc. Here, we are going to present the management of a rare case report of maxillary right lateral incisor-canine pseudotransposition with minimum available space and agenesis of mandibular third molars. © 2022 Innovative Publication, All rights reserved.
Two-Step Calibration Estimator with Double Use of Auxiliary Variable: Method and Application
(Iranian Statistical Society, 2022) Alka Singh; Piyush Kant Rai; Muhammad Qasim
This article introduces a two-step calibration technique for the inverse relationship between study variable and auxiliary variable along with the double use of the auxiliary variable. In the first step, the calibration weights and design weights are set proportional to each other for a given sample. While in the second step, the constant of proportionality is to be obtained on the basis of some di_erent objectives of the investigation viz. bias reduction or minimum Mean Squared Error (MSE) of the proposed estimator. Many estimators based on inverse relationship between x and y have been already developed and are considered to be special cases of the proposed estimator. Properties of the proposed estimator is discussed in details. Moreover, a simulation study has also been conducted to compare the performance of the proposed estimator under Simple Random Sampling Without Replacement (SRSWOR) and Lahiri-Midzuno (L-M) sampling design in terms of percent relative bias and MSE. The benefits of two-step calibration estimator are also demonstrated using real life data. © 2023, (Iranian Statistical Society). All Rights Reserved.