Browsing by Author "Vikram Kumar"

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Andrew's bridge system: A boon for huge ridge defect in aesthetic zone
(Elsevier B.V., 2020) Romesh Soni; Himanshi Yadav; Vikram Kumar
Tooth loss may pose a challenge for prosthetics when several missing teeth are associated with huge vertical and horizontal bone defects due to cleft palate, road traffic accidents, congenital defects etc. This case report presents prosthetic rehabilitation of a 22 year old male patient of cleft lip and palate with missing upper front teeth along with severe ridge defect since 1 year due to surgical intervention in premaxillary region. The extensive soft and hard tissue defect in aesthetic region was evident and it made the prosthetic rehabilitation more challenging. Among treatment options, fixed partial denture (FPD) was not feasible due to long edentulous span and extensive soft and hard tissue loss. Psychologically, patient was not ready for removable prosthesis. Patient was also not ready for next implant or bone augmentation surgery procedure. The patient presented with Kennedy class IV edentulous area with Seibert's class III ridge defect, so fixed-removable prosthesis was planned to compensate soft and hard tissue defect. The patient with several missing teeth and extensive visible bony defect in the anterior region was successfully rehabilitated using fixed-removable Andrew's bridge system. Although it is not commonly used by dentist so this present case report shows effective management of huge defect case by very simple and conservative technique. © 2020 Craniofacial Research Foundation
Coaxial Beam Rotating HPM Mode Converter Using Dielectrics Plates
(Institute of Electrical and Electronics Engineers Inc., 2023) Vikram Kumar; Sivavenkateswara Rao V; Pradip Kumar Jain
The incorporation of the dielectric plates to produce phase delay for propagating waves is a widely employed technique in phase shifters and mode converters. In this article, a compact dielectric plate loaded coaxial beam rotating (CBR) mode converter having high gain and co-polarized (CP) pattern has been proposed for high-power microwave (HPM) applications at X -band. Here, the input transverse magnetic (TM), i.e., TM01 mode, is converted to CP transverse electric (TE), i.e., TE11 likeness mode. The proposed design consists of a circular waveguide (WG) loaded with 12 dielectric polytetrafluoroethylene (PTFE) plates in a radial-azimuthal direction. For 5-mm plate thickness, the proposed design yielded a reflection loss of -20.01 dB with a radiation efficiency of 98.34% and a 17.9 dB gain at 10.084 GHz. Also, the power handling capacity of the proposed structure is predicted as 3.20 GW. Furthermore, the mode conversion is verified by measuring the far-field radiation pattern. Besides, the simulation studies of the thermal behavior of the proposed design are also discussed with the aid of CST Studio Suite. © 2023 IEEE.
Comparative evaluation of biting force and chewing efficiency of all-on-four treatment concept with other treatment modalities in completely edentulous individuals
(Wolters Kluwer Medknow Publications, 2020) Romesh Soni; Himanshi Yadav; Abhishek Pathak; Atul Bhatnagar; Vikram Kumar
Aim: To compare and evaluate biting force and chewing efficiency of all-on-four treatment concept, implant-supported overdenture, and conventional complete denture. Settings and Design: Invivo - comparative study. Materials and Methods: A total of 12 edentulous patients were included in the study and conventional complete dentures were fabricated. Patients were divided into two groups. In Group 1, complete dentures were replaced with implant-supported overdenture, and in Group 2, complete dentures were replaced with hybrid denture supported by all-on-four treatment concept. The biting force was assessed using a bite force sensor and electromyographic recordings were made by electromyogram for masticatory muscles when chewing three different consistencies of foods. Statistical Analysis Used: The data was statistically analyzed using software SPSS version 22.0. Paired t-test was used for intra-group comparison and unpaired t-test was used for intergroup comparison. Results: The difference in biting force and chewing efficiency for all-on-four treatment concept was statistically significant for overdenture and complete denture. The highest biting force and chewing efficiency were observed for all-on-four treatment concept, followed by implant-supported overdenture and complete denture. Conclusion: The study concluded that the completely edentulous individuals with atrophic posterior alveolar ridges can be rehabilitated successfully with improved biting force and chewing efficiency by All-on-four treatment concept. © 2020 Wolters Kluwer Medknow Publications. All rights reserved.
Identification of inhibitors for the collagenase of Leptospira interrogans through docking and molecular simulation
(Springer Nature, 2025) Vikram Kumar; Selvaa Kumar Chellasamy; Nagesh Srikakulam; P. K. Satheeshkumar; Madathiparambil Gopalakrishnan Madanan; Jebasingh Tennyson
Leptospirosis is a neglected tropical zoonotic infection caused by Leptospira interrogans. Collagenase protein is a virulence factor for pathogenic L. interrogans, which facilitates its invasion into Homo sapiens. There is a paucity of chemical compounds that can inhibit the colonisation and infiltration of the pathogen into the host. We looked at the modelled collagenase from L. interrogans for docking studies with ligands and simulations in this study. Based on the results, 4-(3,4-Dihydroxyphenyl)-2-hydroxy-1H-phenalen-1-one, obtained from Musella lasiocarpa (Chinese Dwarf Banana) basically a nutraceuticals and terpene deoxyherqueinone from tea plants and Penicillium herquei was identified as having drug-like properties and demonstrated better binding within the active site pocket of collagenase during the course of protein–ligand docking and simulation. This selected phytochemical can be further taken up for wet-lab-based validation to provide a potential drug to curb this waterborne disease in the near future. © Indian National Science Academy 2024.
Identification of inhibitors for the collagenase of Leptospira interrogans through docking and molecular simulation
(Springer Nature, 2024) Vikram Kumar; Selvaa Kumar Chellasamy; Nagesh Srikakulam; Padikara K. Satheeshkumar; Madanan Gopalakrishnan Madathiparambil; Jebasingh Tennyson
Leptospirosis is a neglected tropical zoonotic infection caused by Leptospira interrogans. Collagenase protein is a virulence factor for pathogenic L. interrogans, which facilitates its invasion into Homo sapiens. There is a paucity of chemical compounds that can inhibit the colonisation and infiltration of the pathogen into the host. We looked at the modelled collagenase from L. interrogans for docking studies with ligands and simulations in this study. Based on the results, 4-(3,4-Dihydroxyphenyl)-2-hydroxy-1H-phenalen-1-one, obtained from Musella lasiocarpa (Chinese Dwarf Banana) basically a nutraceuticals and terpene deoxyherqueinone from tea plants and Penicillium herquei was identified as having drug-like properties and demonstrated better binding within the active site pocket of collagenase during the course of protein–ligand docking and simulation. This selected phytochemical can be further taken up for wet-lab-based validation to provide a potential drug to curb this waterborne disease in the near future. © Indian National Science Academy 2024.
Implant survival in patients with neuropsychiatric, neurocognitive, and neurodegenerative disorders: A meta-analysis
(Wolters Kluwer Medknow Publications, 2021) Rathindra Nath Bera; Richik Tripathi; Bappaditya Bhattacharjee; Akhilesh Kumar Singh; Shweta Kanojia; Vikram Kumar
Neurologic disorders impede oral hygiene measures and routine clinical follow-up, along with the various drugs used may jeopardise oral health and the peri-implant tissue health. A total of 7 studies were considered eligible for the current systematic review. The overall estimated effect was categorized as significant where P < 0.05. Funnel plot was used to assess the publication bias within the studies. Difference in means was used as principal summary measure. P value <0.05 was considered as statistically significant. 1069 implants survived in test group and 4677 implants survived in control group (odds ratio: 2.58, 95% CI: 1.93-3.43) indicating significant success in patient without any disorders or taking medications for these disorders. Subgroup analysis was done to check the implant survival rate in patients taking selective serotonin reuptake inhibitors (SSRI) compared with SSRI non-users. Subgroup analysis showed that SSRI non-users had higher implant survival rate than patients taking SSRI (odds ratio: 2.45, 95% CI: 1.82-3.31). Serotonin significantly inhibits bone mineralization and osteoblast differentiation. The presence of any form of neuropsychiatric or neuromuscular disorders precludes proper oral hygiene and may contribute towards implant failure. © 2021 National Journal of Maxillofacial Surgery.
Influence of different sowing dates and varieties on seed quality of soybean in coastal Andhra Pradesh
(Journal of Pure and Applied Microbiology, 2016) Mukesh Kumar Sheshama; M. Sree Rekha; Sunil Kumar; R.N. Meena; Vikram Kumar
A field experiment was conducted during early rabi season of 2014-15 on clay loam soil at Agricultural College Farm, Bapatla, Andhra Pradesh, to study the influence of sowing dates and varieties on seed quality of soybean in Coastal AP' Early sowing of soybean on 15th September recorded the highest protein content of 34.9 per cent which was on a par with 15th October sowing of soybean and it was significantly superior over 15th November and 15th December sowing. Among the varieties, highest protein content of soybean was recorded with the variety JS-93-05 (35.2 %) which was significantly superior over the other two varieties JS-335 (32.5%) and Local (44.1%). The highest seed quality (Germination %, Seed viability, and seed vigour) of soybean was recorded with soybean sown on 15th September with variety JS-93-05 both at harvest and 30 days after harvest.
Influence of sowing time, varieties and salicylic acid application on different physiological parameters of indian mustard (brassica juncea l)
(Journal of Pure and Applied Microbiology, 2016) Om Prakash Godara; B.L. Kakralya; Sunil Kumar; Vikram Kumar; Rajesh Kumar Singhal
A field experiment was conducted at Agronomy Farm, S.K.N. College of agriculture, Jobner, Jaipur, Rajasthan to evaluate the effect of sowing time, varieties and salicylic acid (SA) application on different physiological parameters (i.e. relative water content, photosynthetic rate, transpiration rate, stomatal conductance, leaf temperature, Membrane stability index, chlorophyll stability index, heat susceptibility index) of Indian mustard. The experiment was laid out in split plot deign and replicated thrice. The experiment consisted of three sowing dates [20th October (timely sowing), 15th November (late sowing) and 30th November (very late sowing)], two varieties [RGN-236, RGN-229] and four levels of Salicylic acid (Control, SA 50 ppm, SA 100 ppm and SA 150 ppm). Physiological traits like relative water content, photosynthetic rate transpiration rate, stomatal conductance, leaf temperature, chlorophyll stability index Content, heat susceptibility index and membrane stability index are directly correlate with heat stress tolerance in crop plant. Results were revealed that effect of different sowing time, varieties and concentration of SA has shown significant effect on all tested physiological parameters of Indian mustard and those are associated with high temperature stress tolerance.
Microwave components and devices for RADAR systems
(Elsevier, 2022) Vikram Kumar; Dileep Kumar Gupta
This chapter discusses the essential components of microwave systems, which are relevant for designing a microwave radar measurement setup. The ways in which transmission lines are used in planar and waveguides lead to requirement for other components in planar or waveguide-based design. With a discussion on some primary antennas, the chapter reviews microwave absorbers and their characteristics. The power dissipation equation is established regarding the absorbing material. A few important microwave sources are discussed. The need for a mode converter in a microwave system leads to the necessary modes obtained from source-generated modes. A network analyzer is also discussed, which has the ability to measure the reflection loss and transmission loss of microwave power. © 2022 Elsevier Inc. All rights reserved.
Multilayered platelet-rich fibrin as a barrier membrane in guided bone regeneration with simultaneous implant placement: A 3-year follow-up
(Jaypee Brothers Medical Publishers (P) Ltd, 2020) Romesh Soni; Aditi Priya; Himanshi Yadav; Vikram Kumar; Nitesh Mishra
Aim: To demonstrate the use of multilayered platelet-rich fibrin (PRF) membranes as a barrier membrane in the guided bone regeneration (GBR) procedure. Background: Ridge deformities, defects, and insufficient volume at the intended implant sites are common challenge. Simultaneous implant placement along with GBR gives benefits of reduced treatment cost, time, and need of additional surgical procedure. Platelet-rich fibrin has a versatile nature and is a regenerative tool in both hard and soft tissue surgery. This case report presented an alternative approach using PRF as a membrane (multilayered) in GBR to correct buccal wall defect in conjunction with implant placement. Case description: A 23-year-old male was referred for rehabilitation of edentulous area concerning to 32 and 33 regions. After clinical and radiological evaluation and discussion of various treatment modalities, GBR with simultaneous implant placement was planned. Ridge augmentation was done in defect using sticky bone formed by bio-oss bone granules of particle size 1.0–2.0 mm and PRF membranes after implant placement. A proper surgical procedure was followed and postoperative follow-up was done from time to time. Conclusion: Sufficient bone volume was achieved through GBR as shown clinically at second-stage surgery done after 4 months. Three years’ follow-up reveals stable implant prosthesis and healthy interdental papilla and gingival tissue. The multilayered PRF membrane is safe, more economical, and may be feasible as a barrier membrane and could be used in some selected scenarios. Clinical significance: Platelet-rich fibrin membranes can act as resorbable barrier and allow faster healing, improve bone formation, provide soft tissue regeneration, and improve the soft tissue profile. © 2020, Jaypee Brothers Medical Publishers (P) Ltd. All rights reserved.
Productivity and profitability of maize (Zea mays) as influenced by tillage practices and green manuring under Eastern Uttar Pradesh conditions
(Indian Society of Agronomy, 2019) Sunil Kumar; R.N. Meena; R.K. Singh; V.K. Srivastava; Vikram Kumar; K. Hemalatha
A field experiment was conducted during the rainy (kharif) and winter (rabi) seasons of 2016–17 and 2017–18 at Varanasi, Uttar Pradesh, to study the effect of different tillage practices and green manuring on productivity and profitability of maize (Zea mays L.)–wheat (Triticum aestivum L.) cropping system. The experiment was laid out in a split-plot design, consisting of 20 treatments. Four different tillage practices, viz. T1, conventional tillage maize–conventional tillage wheat; T2, minimum tillage maize–minimum tillage wheat; T3, minimum tillage maize-zero tillage wheat; and T4, zero tillage maize–zero tillage wheat, were assigned to main plot and 5 summer green-manuring treatments, viz. M1, summer fallowing; M2, dhaincha [Sesbania bispinosa (Jacq.) W. Wight)]; M3, sunnhemp (Crotalaria juncea L.); M4, clusterbean (Cyamopsis tetragonoloba (L) Taub.]; and M5, cowpea [Vigna unguiculata (L.) Walp.], were kept in subplots. The treatment T4 and T1 remaining at par with each other, registered higher yield-attributing characters, grain and stover yields, quality and benefit: Cost (B:C) ratio. In case of summer green manuring, M2 recorded higher yield-attributing characters, grain (5.59 t/ha) and stover (6.61 t/ha) yields, quality, gross returns, net returns and B: C ratio over other treatments, but it was at par with M3. Thus, ZT maize and summer green manure dhaincha residue mulching may be followed to achieve higher yield and profitability in Uttar Pradesh conditions. © 2019, Indian Society of Agronomy. All rights reserved.
Proteomic approach and expression analysis revealed the differential expression of predicted leptospiral proteases capable of ECM degradation
(Elsevier B.V., 2018) Gunasekaran Dhandapani; Thoduvayil Sikha; Sneha M. Pinto; M. Kiran Kumar; Krishna Patel; Manish Kumar; Vikram Kumar; Jebasingh Tennyson; P.K. Satheeshkumar; Harsha Gowda; T.S. Keshava Prasad; M.G. Madanan
Leptospira, the causative agent of leptospirosis is known to have many proteases with potential to degrade extracellular matrix. However, a multipronged approach to identify, classify, characterize and elucidate their role has not been attempted. Our proteomic approach using high-resolution LC-MS/MS analysis of Triton X-114 fractions of Leptospira interrogans resulted in the identification of 104 proteases out of 130 proteases predicted by MEROPS. In Leptospira approximately 3.5% of the genome complements for proteases, which include catalytic types of metallo-, serine-, cysteine-, aspartic-, threonine- and asparagine- peptidases. Comparison of proteases from different serovars revealed that M04, M09B, M14A, M75, M28A, A01 and U73 protease families are exclusively present in pathogenic form. The M23 and S33 protease families are represented with >14 members in Leptospira. The differential expression under physiological temperature (37 °C) and osmolarity (300 mOsM) showed that proteases belonging to the catalytic type of Metallo-peptidases are upregulated significantly in pathogenic conditions. In silico prediction and characterization of the proteases revealed that several proteases are membrane anchored and secretory, classical as well as non-classical system. The study demonstrates the diversity and complexity of proteases, while maintaining conservation across the serovars in Leptospira and their differential expression under pathogenic conditions. © 2018 Elsevier B.V.
Sustainable intensification in cropping systems through inclusion of legumes
(Elsevier, 2022) Shivani Lalotra; Sandeep Kumar; Ram Swaroop Meena; Vikram Kumar
Resource degradation, climate change, and population pressure are a threat to the food production system. Legumes-based SI of cropping systems could also meet current challenges of food security and environmental sustainability. Sustainability implies producing sufficient food without ecological collapse while minimizing off-farm use of synthetic inputs. Legumes are known for resource conservation and their sustainable use. Legumes fix atmospheric nitrogen (N) subsequently supplies 20–60 kg N for component and succeeding crop in a system. Besides this, legumes add carbon to the soil, improve ecological biodiversity, functions ecosystem services, and improve nutrient cycling. Therefore, this chapter aimed to bring the attention of farmers, researchers, and policy makers toward the sustainable inclusion of legumes in the existing cropping system. Legumes-based intensification through crop rotation, intercropping, cover cropping, green manuring, legume-based pasture management, hedgerows planting, and legume-based land management is being advocated for better crop yield (10%–25% higher). Sustainable inclusion of legumes in the existing cropping system is a current need for maintenance of ecological balance and curtailing input requirements. © 2022 Elsevier Inc. All rights reserved.