Effect of Heat Generation on Forced Convection Through a Porous Saturated Duct

Prakash, D.,Muthtamilselvan, M.,Doh, Deog-Hee Springer-Verlag 2012 Transport in porous media Vol.95 No.2

A proposed organic Schottky barrier photodetector for application in the visible region

A.D.D. Dwivedi,Arun Kumar Singh,Rajiv Prakash,P. Chakrabarti 한국물리학회 2010 Current Applied Physics Vol.10 No.3

The fabrication and characterization of an organic photodetector (OPD) in the form of ITO coated glass/polycarbazole (PCz)/Al Schottky contact is reported. The device has been fabricated in our laboratory for the first time using the polymer synthesized by us. The device has been subsequently characterized in respect of electrical and optical properties in order to explore its potential for possible use as a detector in the visible region at 650 nm. It is observed that the detector exhibits a reasonably high value of peak detectivity (~6 × 106 cm Hz1/2W-1) near zero bias voltage at V = 0.2 V.

Resistance controllability and variability improvement in a TaO_x-based resistive memory for multilevel storage application

Prakash, A.,Deleruyelle, D.,Song, J.,Bocquet, M.,Hwang, H. American Institute of Physics 2015 APPLIED PHYSICS LETTERS Vol.106 No.23

An effective and facile synthesis of hydroxyapatite powders using oxalic acid―ethylene glycol mixture

D. Gopi,P.R. Bhalaji,V.C.A. Prakash,A.K. Ramasamy,L. Kavitha,J.M.F. Ferreira 한국물리학회 2011 Current Applied Physics Vol.11 No.3

A method to synthesize hydroxyapatite (HAP) ceramic powders using a metal-oxalate route with calcium chloride and phosphoric acid as calcium and phosphorus precursors respectively is described. Ethylene glycol was used as a reaction medium and oxalic acid as a chelating agent. The resulting HAP powders were calcined at 600 ℃ for 6 h and subsequently sintered at 900 ℃ for 2 h. FT-IR, XRD and SEM techniques were employed for the characterization of the synthesized particles. Moreover, the influence of reaction temperature on the HAP formation was also studied. The results have shown successful formation of the crystalline, uniform sized, uniform shaped and stoichiometric HAP powders at a reaction temperature of 75 ℃ which was found to be the optimum temperature for the preparation. The grain size of the synthesized sample was 680 nm in length and 440 nm in width.

Promoting medicinal plants cultivation as a tool for biodiversity conservation and livelihood enhancement in Indian Himalaya

Prakash C. Phondani,Indra D. Bhatt,Vikram S. Negi,Bhagwati P. Kothyari,Arvind Bhatt,Rakesh K. Maikhuri 국립중앙과학관 2016 Journal of Asia-Pacific Biodiversity Vol.9 No.1

The present paper discusses the development of a participatory approach to promote medicinal and aromatic plant (MAP) cultivation as a tool for biodiversity conservation and livelihood enhancement in Champawat district of Uttarakhand state in India. People perception analysis revealed that farmers were dependent solely on the wild collection of MAPs before the initiation of the National Agriculture Innovation Project. However, they later engaged in cultivation practices. During the course of study, the propagation protocols of 11 selected MAPs of that area were developed and a cost-benefit analysis was performed. A series of meetings and exposure visits were organized and a memorandum of understanding was simultaneously signed between farmers and traders for promoting a buy-back system of MAPs. One hundred thirty-two farmers adopted MAP cultivation in 14 hectares of land. This approach provides opportunities for farmers to build skills, knowledge, and self confidence, and conserve MAP diversity in their natural habitat.

QTLs Associated with Resistance in Soybean PI567516C to Synthetic Nematode Population Infecting cv. Hartwig

Prakash R. Arelli,Vergel C. Concibido,Lawrence D. Young 한국작물학회 2010 Journal of crop science and biotechnology Vol.13 No.3

Worldwide, soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is the most destructive pathogen of soybean [Glycine max (L.) Merr.]. Crop losses are primarily mitigated by the use of resistant cultivars. Nematode populations are variable and have adapted to reproduce on resistant cultivars over time because resistance primarily traces to two soybean accessions, Plant Introduction (PI) 88788 and Peking. Soybean cultivar Hartwig, derived primarily from PI437654, was released for its comprehensive resistance to most SCN populations. A synthetic nematode population (LY1) was recently selected for its reproduction on Hartwig. The LY1 nematode population currently infects known sources of resistance except soybean PI567516C; however, the resistance to LY1 has not been characterized. The objective of this study was to identify quantitative trait loci (QTLs) underlying resistance to the LY1 SCN population in PI567516C, identify diagnostic DNA markers for the LY1 resistance, and confirm their utility for markerassisted selection (MAS). Resistant soybean line PI567516C was crossed to susceptible cultivar Hartwig to generate 105 recombinant inbred lines (F2-derived F5 families). QTLs were mapped using simple sequence repeats (SSRs) covering 20 Linkage Groups (LGs) and three diagnostic markers, Satt592, Satt331, and Sat_274, were identified on LG O. These markers have a combined efficacy of 90% in identifying resistant lines in a second cross that has been generated by crossing a susceptible cultivar 5601T with resistant PI567516C. F2-derived F4 segregating population was used in MAS to identify resistant lines.

Is Weight-Based Adjustment of Automatic Exposure Control Necessary for the Reduction of Chest CT Radiation Dose?

Priyanka Prakash,Mannudeep K. Kalra,Matthew D. Gilman,Jo-Anne O. Shepard,Subba R. Digumarthy 대한영상의학회 2010 Korean Journal of Radiology Vol.11 No.1

Objective: To assess the effects of radiation dose reduction in the chest CT using a weight-based adjustment of the automatic exposure control (AEC) technique. Materials and Methods: With Institutional Review Board Approval, 60 patients (mean age, 59.1 years; M:F = 35:25) and 57 weight-matched patients (mean age, 52.3 years, M:F = 25:32) were scanned using a weight-adjusted AEC and nonweight-adjusted AEC, respectively on a 64-slice multidetector CT with a 0.984:1 pitch, 0.5 second rotation time, 40 mm table feed/rotation, and 2.5 mm section thickness. Patients were categorized into 3 weight categories; < 60 kg (n = 17), 60-90 kg (n = 52), and > 90 kg (n = 48). Patient weights, scanning parameters, CT dose index volumes (CTDIvol) and dose length product (DLP) were recorded, while effective dose (ED) was estimated. Image noise was measured in the descending thoracic aorta. Data were analyzed using a standard statistical package (SAS/STAT) (Version 9.1, SAS institute Inc, Cary, NC). Results: Compared to the non-weight-adjusted AEC, the weight-adjusted AEC technique resulted in an average decrease of 29% in CTDIvol and a 27% effective dose reduction (p < 0.0001). With weight-adjusted AEC, the CTDIvol decreased to 15.8, 15.9, and 27.3 mGy for the < 60, 60-90 and > 91 kg weight groups, respectively, compared to 20.3, 27.9 and 32.8 mGy, with non-weightadjusted AEC. No significant difference was observed for objective image noise between the chest CT acquired with the non-weight-adjusted (15.0 ± 3.1) and weight-adjusted (16.1 ± 5.6) AEC techniques (p > 0.05). Conclusion: The results of this study suggest that AEC should be tailored according to patient weight. Without weight-based adjustment of AEC, patients are exposed to a 17 - 43% higher radiation-dose from a chest CT. Objective: To assess the effects of radiation dose reduction in the chest CT using a weight-based adjustment of the automatic exposure control (AEC) technique. Materials and Methods: With Institutional Review Board Approval, 60 patients (mean age, 59.1 years; M:F = 35:25) and 57 weight-matched patients (mean age, 52.3 years, M:F = 25:32) were scanned using a weight-adjusted AEC and nonweight-adjusted AEC, respectively on a 64-slice multidetector CT with a 0.984:1 pitch, 0.5 second rotation time, 40 mm table feed/rotation, and 2.5 mm section thickness. Patients were categorized into 3 weight categories; < 60 kg (n = 17), 60-90 kg (n = 52), and > 90 kg (n = 48). Patient weights, scanning parameters, CT dose index volumes (CTDIvol) and dose length product (DLP) were recorded, while effective dose (ED) was estimated. Image noise was measured in the descending thoracic aorta. Data were analyzed using a standard statistical package (SAS/STAT) (Version 9.1, SAS institute Inc, Cary, NC). Results: Compared to the non-weight-adjusted AEC, the weight-adjusted AEC technique resulted in an average decrease of 29% in CTDIvol and a 27% effective dose reduction (p < 0.0001). With weight-adjusted AEC, the CTDIvol decreased to 15.8, 15.9, and 27.3 mGy for the < 60, 60-90 and > 91 kg weight groups, respectively, compared to 20.3, 27.9 and 32.8 mGy, with non-weightadjusted AEC. No significant difference was observed for objective image noise between the chest CT acquired with the non-weight-adjusted (15.0 ± 3.1) and weight-adjusted (16.1 ± 5.6) AEC techniques (p > 0.05). Conclusion: The results of this study suggest that AEC should be tailored according to patient weight. Without weight-based adjustment of AEC, patients are exposed to a 17 - 43% higher radiation-dose from a chest CT.

Crystallite Size Effect on Voltage Tunable Giant Dielectric Permittivity of Nanocrystalline CuO

T. Prakash,B.S. Murty,A.R. Kaskhedikar,P.D. Peshwe 대한금속·재료학회 2013 ELECTRONIC MATERIALS LETTERS Vol.9 No.1

The effect of crystallite size and applied DC bias voltage on dielectric permittivity of CuO was studied using impedance spectroscopy. The measurements were performed at room temperature in a wide frequency range of 1 Hz to 1 MHz under applied DC bias voltages from 0 to 3 V in the periodic increment of 0.2 V. The observed applied DC bias voltage effect on giant dielectric constant (ε' = 104) were analyzed with ‘grain boundary double Schottky potential barrier height model’. The percentage of tunability (T %) at the frequency 100 Hz is found to be 45.5% for the case of nanocrystalline CuO in contrast to 0% tunability in bulk CuO.

Comparison of outcomes of free-hand 2-dimensional ultrasound-guided versus navigated 3-dimensional ultrasound-guided biopsy for supratentorial tumours: a single-institution experience with 125 cases

Aditya D. Patil,Vikas Singh,Prakash M. Shetty,Aliasgar V. Moiyadi 대한초음파의학회 2019 ULTRASONOGRAPHY Vol.38 No.3

Purpose: The purpose of this study was to evaluate the relative utility and benefits of free-hand 2-dimensional intraoperative ultrasound (FUS) and navigated 3-dimensional intraoperative ultrasound (NUS) as ultrasound-guided biopsy (USGB) techniques for supratentorial lesions. Methods: All patients who underwent USGB for suspected supratentorial tumours from January 2008 to December 2017 were retrospectively analyzed. The charts and electronic medical records of these patients were studied. Demographic, surgical, and pathological variables were collected and analyzed. The study group consisted of patients who underwent either FUS or NUS for biopsy. Results: A total of 125 patients (112 adults and 13 children) underwent USGB during the study period (89 FUS and 36 NUS). NUS was used more often for deep-seated lesions (58% vs. 18% for FUS, P<0.001). The mean operating time for NUS was longer than for FUS (156 minutes vs. 124 minutes, P=0.001). Representative yield was found in 97.7% of biopsies using FUS and in 100% of biopsies using NUS (diagnostic yield, 93.6% and 91.3%, respectively). The majority of lesions (89%) were high-grade gliomas or lymphomas. Postoperative complications were more common in the NUS group (8.3% vs. 1.2%), but were related to the tumour location (deep). Conclusion: Despite the longer operating time and higher rate of postoperative complications, NUS has the benefit of being suitable for biopsies of deep-seated supratentorial lesions, while FUS remains valuable for superficial lesions.

Shrinkage estimation in exponential type-II censored data under LINEX loss

Gyan Prakash,D.C. Singh 한국통계학회 2008 Journal of the Korean Statistical Society Vol.37 No.1

This paper deals with the study of the performance of the shrinkage testimators under the invariant version of LINEX lossfunction for the scale parameter of an exponential distribution when type-II censored data are available.