A Radiological Study of the Association of Facet Joint Tropism and Facet Angulation With Degenerative Spondylolisthesis

Ravi Ranjan Rai,Yash Shah,Siddharth Shah,Nigil Sadanandan Palliyil,Samir Dalvie 대한척추신경외과학회 2019 Neurospine Vol.16 No.4

Objective: To study the association of facet joint angulation and joint tropism with degenerative spondylolisthesis (DS) through a comparison with a matched control group. Methods: This radiographic study was carried out in 2 groups of 45 patients each. Group A contained patients with single-level DS, while group B (control) contained non-DS patients with similar age and degeneration who underwent surgery for disc prolapse or lumbar stenosis. DS was diagnosed based on translation of ≥3 mm on standing lateral radiography. Axial magnetic resonance imaging from L3 to S1 was utilized to assess the angulation of facet joints in relation to the coronal plane; a difference of ≥8° was considered to indicate tropism. Results: Among 45 patients with DS, 15 were males and 30 females. Their mean age was 62.2 years. Facet tropism was identified in 20 of 45 patients at the level of DS, 12 patients at a level proximal to DS, and 15 patients at a level distal to DS. Facet tropism was found in 7 of the 45 patients in group B. At L3–4, facet tropism was observed in 13 patients (28.88%) in group A and 2 (4.44%) in group B. At L4–5, tropism was observed in 19 patients (42.22%) in group A and 5 (11.11%) in group B. At L5–S1, tropism was seen in 17 patients (37.77%) in group A and 2 (4.44%) in group B. Group A showed a significantly higher prevalence of multilevel facet tropism and tropism at levels adjacent to the DS level. A higher average angulation of facet joints was observed in the DS group, but the difference was not statistically significant at all levels. Conclusion: The present study documented a statistically significant relationship between facet tropism and DS. A higher prevalence of facet tropism was also found in DS patients at non-DS levels, which is a novel observation. This finding supports the argument that facet tropism is a pre-existing morphological variation contributing to the development of DS, not a result of secondary remodelling.

Novel Vertical GAA-AlGaN/GaN Dopingless MIS-HEMT: Proposal and Investigation

Ravi Ranjan,Nitesh Kashyap,Ashish Raman 한국전기전자재료학회 2021 Transactions on Electrical and Electronic Material Vol.22 No.4

This paper presents a gate all around (GAA) AlGaN/GaN HEMT (GAA-MIS-HEMT) with AlN as an interfacial passivation layer. Gate all around technique is used to improve the performance of device such as carrier concentration, electric field and current density at the interface of AlGaN & GaN. The enhanced control over the 2DEG due to gate all around structure helped in attaining superior performance. Al2O3 is used as a dielectric. The results of GAA-MIS-HEMT are compared with planar-MIS-HEMT, which shows that the GAA-MIS-HEMT provides better ON-state current, OFF-state current, transconductance, cutoff frequency (11 GHz) and ON-state to OFF-state current ratio (10 11 ), ON-resistance (0.9Ω-cm2 ) and subthreshold slope (63 mV/dec). All the layers of proposed structure are dopingless.

Undescended cecum with accessory right colic artery: a rare case report

Praveen Kumar Ravi,Manisha Rajanand Gaikwad,Pravash Ranjan Mishra,Naina Santosh Wakode,Prabhas Ranjan Tripathy,E. Tripati Patro,Babita Kujur,Santosh Laxman Wakode 대한해부학회 2017 Anatomy & Cell Biology Vol.50 No.3

Midgut malrotation and incomplete rotation are common causes of neonatal intestinal obstruction. At end of 10 week of intrauterine life, cecum will be placed in subhepatic region temporarily and descends to right lower quadrant by eleventh week. Arrest of cecum in subhepatic region or undescended cecum is a rare congenital anomaly of mid gut. Usually, it remains asymptomatic and is diagnosed incidentally. If any pathology occurs in anomalous part, like appendicitis then the diagnosis and treatment will be challenging in all age groups. Variation in blood supply have also been reported with anomalies leading to iatrogenic injuries during colonoscopy and surgeries. Lack of knowledge of these rare variations may lead to delayed diagnosis of appendicitis leading to perforation and surgical emergencies. In the present case, we describe an undescended cecum and its associated variation in branching pattern of superior mesenteric artery.

BF2-Complexes of Carbazole–Benzimidazole Conjugates: Synthesis, Structures, and Spectroscopic Properties

Ranjan Dutta,Dikhi Firmansyah,유재덕,Ravi Kumar,Endale Mulugeta Beza,조홍일,옥강민,이창희 대한화학회 2017 Bulletin of the Korean Chemical Society Vol.38 No.10

A series of carbazole–benzimidazole conjugates and corresponding BF2-complexes (BODIPYs) are synthesized and characterized. Carbazole–benzimidazole conjugates are synthesized by the condensation of 1-formyl carbazole and phenylene diamines in good yields. Various substituents are introduced into the benzimidazole moiety and subsequent reaction with BF3•Et2O afforded the BF2-complexes in moderate to good yield. The structural and photophysical properties of the synthesized fluorophores are investigated with various spectroscopic techniques such as UV/Vis and fluorescence spectroscopy, cyclic voltammetry and X-ray crystallography.

Estimating Normalized Attention of Viewers on Account of Relative Visual Saliency of Faces (NRVS)

Ravi kant kumar,Jogendra Garain,Goutam Sanyal,Dakshina Ranjan Kisku 보안공학연구지원센터 2015 International Journal of Software Engineering and Vol.9 No.7

Humans psychological and behavioral understanding often lead to make natural decision which accurately identifies and remembers the faces which are highly appreciated or criticized by themselves in comparing to the normal viewed faces, in terms of beauty, ugliness or unique appearance. It happens due to human psychology of being biased towards the salient face in the process of face recognition and identification. This paper attempts a novel method to measure, how our attention is more restricted towards some particular faces in the crowd. This restricted attention is strongly guided by the relative visual saliency of these faces. In this paper, normalized relative visual saliency (NVRS) of the faces is evaluated using their intensity values modulated with respective spatial distance. Experiment has been carried out on test image dataset via bottom up approach. The experimental results are found to be encouraging and accuracy has also been measured exhibiting efficacy of the proposed approach.

Performance Analysis of Normally-on Dual Gate Algan/Gan Hemt

Manisha Rao,Ravi Ranjan,Nitesh Kashyap,Rakesh Kumar Sarin 한국전기전자재료학회 2021 Transactions on Electrical and Electronic Material Vol.22 No.5

This paper presents the novel normally-on dual gate (DG) AlGaN/GaN high electron mobility transistor. At high frequency, the dual gate structure gives superlative immunity over short channel eff ects. Multiple 2DEG channel regions in dual gate AlGaN/GaN HEMT improves the transport characteristics, charge control and gives better linearity. The high carrier mobility and electron saturation velocity contribute to the high switching frequency of DG HEMT. The drain characteristics of single gate HEMT and dual gate HEMT are compared and DG HEMT outstands in drain current. The various analog and linearity parameters are investigated for DG HEMT. The performance analysis provides better transconductance, capacitance, cut off frequency, subthreshold slope and on-resistance simulations represents the potential of DG HEMT. The DG HEMT provides 1100 mA/mm I ON , 550 mS/mm transconductance and 11 GHz cutoff frequency at V gs = 2 V. The high drain current, better transconductance and cutoff frequency results in better sensitivity of device.

Cohort Selection of Specific User Using Max-Min-Centroid-Cluster (MMCC) Method to Enhance the Performance of a Biometric System

Jogendra Garain,Ravi Kant Kumar,Goutam Sanyal,Dakshina Ranjan Kisku 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.6

Selection of cohort models plays a vital role to increase the accuracy of a biometric authentication system as well as to reduce the computational cost. This paper proposes a novel approach for cohort selection called Max-Min-Centroid-Cluster (MMCC) method. The clusters of cohorts are generated by K-means clustering technique. The union of the clusters having largest and smallest centroid value is taken as cohort subset. The cohort scores, after normalization using different cohort based score normalization techniques, are used in authentication process of the system. Evaluation has been carried out on FEI face datasets. The performance of this novel methodology is analyzed using T-norm and Aggarwal (max rule) normalization techniques. Experimental results exhibit the efficacy of the proposed method.

Defense Inducer Compounds Up-regulated the Peroxidase, Polyphenol Oxidase, and Total Phenol Activities against Spot Blotch Disease of Wheat

Puja Kumari,Chandrashekhar Azad,Ravi Ranjan Kumar,Jyoti Kumari,Kumar Aditya,Amarendra Kumar 한국식물병리학회 2023 Plant Pathology Journal Vol.39 No.2

Spot blotch disease of wheat caused by Bipolaris sorokiniana (Sacc.) Shoem is considered as an economically important disease which affects all the growing stages of wheat crop. Therefore, it is important to search some effective management strategies against the spot blotch pathogen. Some synthetic elicitor compounds (salicylic acid, isonicotinic acid, and chitosan) and nano-particles (silver and aluminum) were tested against the pathogen to observe the change in biochemical activity and defense action of wheat plant against spot blotch disease. All the tested elicitor compounds and nano-particles showed a significant increase in activity of peroxidase, polyphenol oxidase (PPO), and total phenol over control. The highest increase in activity of peroxidase was recorded at 72 h from chitosan at 2 mM and 96 h from silver nano-particle at 100 ppm. Maximum PPO and total phenol activity were recorded from chitosan at 2 mM and silver nano-particle at 100 ppm as compared to pathogen-treated and healthy control. The lowest percent disease index, lowest no. of spots/leaf, and no. of infected leaves/plant were found in silver nano-particle at 100 ppm and chitosan at 2 mM, respectively. The use of defense inducer compounds results in significantly up-regulated enzymatic activity and reduced spot blotch disease. Therefore, chitosan and silver nanoparticle could be used as alternative methods for the management of spot blotch disease.

Design and Investigation of Dual Dielectric Recessed-Gate AlGaN/GaN HEMT as Gas sensor Application

Ashish Raman,Soumya Prasanna Chattopadhyay,Ravi Ranjan,Naveen Kumar,Deepti Kakkar,Rajneesh Sharma 한국전기전자재료학회 2022 Transactions on Electrical and Electronic Material Vol.23 No.6

This paper presents a highly sensitive Recessed Gate/source/drain AlGaN/GaN HEMT (RG-AlGaN/GaN HEMT) based Carbon Monoxide gas sensors. Many types of Carbon Monoxide (CO) gas sensor have already been demonstrated experimentally. The deeply etched recessed gate based HEMT form highly sensitive 2DEG for small change in gate metal oxide. Copper Oxide and Cerium Oxide are used as a gate electrode in CO gas detection and these metal oxides are reactively sensitive to CO gas molecules. Because of the change in the work function of gate metal oxide due to the presence of gas deposition on it, there is the change in I off , I on , SS and V th which can be taken as sensitivity parameter for sensing the gas molecules. For a change in work function till 700meV using various steps sizes, RG-AlGaN/GaN HEMT based CO gas sensor shows highly sensitivity with respect to device characteristics parameters.

The Effect of Head Loading on Cervical Spine in Manual Laborers

Dave Bharat R.,Krishnan Ajay,Rai Ravi Ranjan,Degulmadi Devanand,Mayi Shivanand 대한척추외과학회 2021 Asian Spine Journal Vol.15 No.1

Study Design: A prospective case–control study.Purpose: To determine the effect of axial loading on the cervical spine when weights are carried on the head.Overview of Literature: Traditionally, carrying weights on the head has been a common practice in developing countries. The laborers working in agriculture, construction, and other industries, as well as porters at railway platforms, are required to lift heavy weights. Since controversy exists regarding carrying weights on the head, we decided to evaluate its effect on the cervical spine.Methods: The study comprised 62 subjects. Of this number, 32 subjects (group A) were unskilled laborers from the construction industry; the other 30 subjects (group B) were in the control group and had never previously carried heavy weights on their heads. Cervical spine radiographs were taken for all the 62 subjects. Subjects in group A were asked to carry a load (approximately 35 kg) on their heads and walk for about 65 m, with their cervical spine radiographs taken afterward.Results: The mean ages of patients in groups A and B were 27.17 and 25.75 years, respectively. The mean cervical lordosis observed in group A (18.96°) was dramatically less compared with group B (25.40°), showing a further decrease in head loading (3.35°). Five subjects had a reversal of lordosis (−5.61°). A statistically significant reduction in disc height and listhesis was observed when the load was carried on the head with a further decrease after walking with the load. Accelerated degenerative changes, particularly affecting the upper cervical spine, were observed in head loaders.Conclusions: Carrying a load on the head leads to accelerated degenerative changes, which involve the upper cervical spine more than the lower cervical spine and predisposes it to injury at a lower threshold. Thus, alternative methods of carrying loads should be proposed.