nitin choudhary - Academia.edu (original) (raw)
Papers by nitin choudhary
International Journal of Clinical Trials, 2021
Background: Low backache (LBA) with lumbosacral radiculopathy is the most challenging musculoskel... more Background: Low backache (LBA) with lumbosacral radiculopathy is the most challenging musculoskeletal problem for its therapeutic management and cause of LBA with radiculopathy is a prolapsed disc. Epidural steroidal injection (ESI) are used in the management of the patients with sub-acute or chronic LBA with radiculopathy, not responding to conservative treatment. The most common cause being, lumbar disc disease, is confirmed via magnetic resonance imaging having high sensitivity and specificity. The aim of study was to check the efficacy of ESI in patients of sub-acute or chronic low backache with radiculopathy due to herniated disc.Methods: The study was conducted over 200 patients reporting our OPD during Dec 2017- Feb 2018 with complaints of LBA with radiculopathy, not responding to conservative treatment. Maximum of 3 ESI were given with two weeks of interval in between. The patients were assessed using VAS scoring system.Results: 77.5% patients got improvement in symptoms, a...
The community-developed, free and open-source solar data analysis environment for Python.
Saudi Journal of Anaesthesia, 2021
As the motivation to potentially allow for a more expansive role of opioid-sparing anaesthesia in... more As the motivation to potentially allow for a more expansive role of opioid-sparing anaesthesia in various surgical specialities transpire with new zeal, promising evidence needs to be accumulated to substantiate the same. Appropriate to this context, the index case series highlight the beneficial effects of an intraoperative magnesium sulphate infusion on perioperative hemodynamic profile and postoperative recovery in patients undergoing intracranial cerebral aneurysm surgery.
physica status solidi (RRL) – Rapid Research Letters, 2021
Harnessing the recently discovered ferroelectricity in scandium aluminum nitride (ScxAl1−xN) for ... more Harnessing the recently discovered ferroelectricity in scandium aluminum nitride (ScxAl1−xN) for the realization of integrated electronic and electromechanical devices requires a low‐temperature growth process that enables versatile control over film thickness, stoichiometric composition, and stress. Herein, a reactive magnetron sputtering process that enables extreme scaling of film thickness and tuning of composition and residual stress is reported on. Highly crystalline ScxAl1−xN films with thicknesses of over 25–250 nm with scandium concentrations of over 22–30 at% are sputtered using a segmented target created from scandium and aluminum tiles. The residual stress in the films is widely tuned from highly compressive to tensile using a pressure‐ and gas‐flow‐independent approach based on adjusting the electrical termination of the targets. The crystallinity, texture, and ferroelectric characteristics are measured for ScxAl1−xN films with different thicknesses, compositions, and residual stresses. The results highlight the consistent crystallinity and ferroelectric properties despite extreme thickness miniaturization to sub‐50 nm, and the large dependence of the coercive field on the residual stress and Sc concentration.
IEEE Electron Device Letters, 2021
This letter reports intrinsically switchable ultra- and super-high-frequency Lamb-mode resonators... more This letter reports intrinsically switchable ultra- and super-high-frequency Lamb-mode resonators based on the use of ferroelectricity in scandium aluminum nitride (Sc<sub>x</sub>Al<sub>1−x</sub>N) films. Highly crystalline 200nm-thick Sc<sub>0.22</sub>Al<sub>0.78</sub>N film is sputtered using segmented-target reactive magnetron sputtering, and interdigitated electrodes are patterned to create one-port resonators operating in symmetric Lamb modes. The resonators are intrinsically switched using the ferroelectric behavior in Sc<sub>0.22</sub>Al<sub>0.78</sub>N film and through polarization switching at one of the terminals, resulting in a zero-sum electromechanical coupling factor (<inline-formula> <tex-math notation="LaTeX">${k}_{t}^{2}$ </tex-math></inline-formula>). Resonators with frequencies over 0.45 – 6 GHz, frequency <inline-formula> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> quality factor product (<inline-formula> <tex-math notation="LaTeX">${f}_{s}\times {Q}$ </tex-math></inline-formula>) as high as <inline-formula> <tex-math notation="LaTeX">$4\times 10^{12}$ </tex-math></inline-formula>, and and <inline-formula> <tex-math notation="LaTeX">$k_{t}^{2} \times Q$ </tex-math></inline-formula> product exceeding29 aredemonstrated. The intrinsic switchability of resonators is characterized using 100ms triangular monopolar pulses, resulting in an admittance switching isolation as high as 15dB.
International Journal of Research in Orthopaedics, 2020
Background: Fractures of the lateral condyle of the humerus in children are common injuries. If d... more Background: Fractures of the lateral condyle of the humerus in children are common injuries. If displaced or unstable they may require surgical reduction and fixation with Kirschner wires (K-wires). These may be passed through the skin and left exposed or buried subcutaneously.Methods: A prospective study was carried out in department of orthopaedics at my college from January 2019 to March 2020. A total number of 37 subjects were included in the study.Results: Patients were followed for a period of 3 months and results were drawn on basis of union, infection, carrying angle at the elbow, and range of motion (ROM) which was assessed by clinico-radiological means.Conclusions: Buried wire group has shown better union rate than exposed group, wires could be removed under local anaesthesia thereby avoiding any major procedure and also the risk of infection is low making this a better option than the exposed cohort.
Indian Journal of Clinical Anaesthesia, 2020
Large retrosternal goitre is a challenge to the anaesthesiologist and the surgeon. We describe th... more Large retrosternal goitre is a challenge to the anaesthesiologist and the surgeon. We describe the successful anaesthetic management of a 44 year old male patient with extensive retrosternal goitre with severe tracheal compression, operated for total thyroidectomy under general anaesthesia by combined cervical approach and sternotomy. A multidisciplinary team approach with surgical colleagues allowed successful management of the patient.
Indian Journal of Clinical Anaesthesia, 2020
Introduction: Central venous line placement is one of the essential procedures in the treatment o... more Introduction: Central venous line placement is one of the essential procedures in the treatment of critically ill patients admitted in the intensive care unit. Central venous catheterization is required not only for providing a route for delivery of the caustic or critical medications but it also allows for the measurement of central venous pressure. Being an invasive procedure it has a learning curve and is associated with many complications. Hence, we conducted the study comparing catheterization of internal jugular vein by ultrasound guided versus landmark approach, with respect to the ease of insertion and related complications in Intensive Care Unit (I.C.U.) patients. Materials and Methods: 150 patients admitted in the I.C.U, fulfilling the inclusion criteria were divided into two groups based on computer generated randomization table namely: group A (landmark technique) and group B (USG technique) comprising of 75 patients in each group. In landmark approach, the internal jugular vein was located at the apex of triangle formed by the sterna and clavicular heads of sternocleidomastoid muscle and needle was directed towards the ipsilateral nipple when advanced through skin, lateral to the carotid artery pulsations with artery being pushed medially. In USG guided approach, the linear USG probe of 7 MHz connected to a real-time Kontron Medical ultrasound unit, was used with standard two-dimensional (2D) ultrasound imaging to identify the IJV. Catheterization was performed real-time by placing the transducer of the ultrasound parallel and superior to clavicle, over the groove between the two heads of the sternocleidomastoid muscle (SAX view). A postprocedure x-ray of chest was done as early as possible to assess the placement of CVC and rule out any complication. Results: The two groups were comparable in age, sex and body mass index. There was no statistically significant difference in the mean number of attempts taken for catheterization of IJV between the two groups (p-value=0.124). However, the mean time taken for cannulation of IJV was found to be significantly lower in the USG group as compared to the landmark group (p-value=0.03). The overall rate of complications was significantly higher in group A (p=0.012). Conclusion: Ultrasonography guidance significantly reduced the total procedural time and the rate of complications during internal jugular vein cannulation compared to the landmark technique.
International Journal of Research in Medical Sciences, 2020
Background: COVID-19 pandemic effects are still being elucidated. Stay-at-home orders issued duri... more Background: COVID-19 pandemic effects are still being elucidated. Stay-at-home orders issued during peak of COVID-19 and social distancing as lockdown measures compounded with COVID-19 concerns have caused significant disruptions in daily life. One notable effect of these variables may be a change in the number of emergency department (ED) visits. This study aims to investigate the effects of COVID-19 on ED visits, and possible reasons for changes.Methods: Retrospective analysis using data for ED visits and procedures performed in the orthopaedics department of GMC Jammu were collected from the record section of GMC Jammu for four months prior and post implementation of lockdown and results were deduced with regards to the comparison in the number of visits, admissions and surgeries done pre and post-lockdown period.Results: The mean number of ED visits/admissions per day for the last four months of available data post lockdown due to COVID-19 pandemic was significantly less than th...
Applied Physics Letters, 2019
Emulating the human brain's circuitry composed of neurons and synapses is an emerging area of... more Emulating the human brain's circuitry composed of neurons and synapses is an emerging area of research in mitigating the “von Neumann bottleneck” in present computer architectures. The building block of these neuromorphic systems—the synapse—is commonly realized with oxide-based or phase change material-based devices, whose operation is limited by high programming currents and high reset currents. In this work, we have realized nonvolatile resistive switching MoS2/graphene devices that exhibit multiple conductance states at low operating currents. The MoS2/graphene devices exhibit essential synaptic behaviors, such as short and long-term potentiation, long-term depression, and the spike timing dependent plasticity learning rule. Most importantly, they exhibit a near-linear synaptic weight update, without any abrupt reset process, allowing their use in unsupervised learning applications. These electronic synapses are built with chemical vapor deposited MoS2 and graphene, demonstr...
Madridge Journal of Nanotechnology & Nanoscience, 2018
We studied the influence of titanium dioxide (TiO 2) concentration on the structural and optical ... more We studied the influence of titanium dioxide (TiO 2) concentration on the structural and optical properties of vanadium pentoxide (V 2 O 5) thin films deposited on amorphous glass substrate using pulsed laser deposition technique. TiO 2 doping into V 2 O 5 matrix revealed an interesting morphological change from an array of high density pure V 2 O 5 nanorods (~140 nm) to granular structure inTiO 2-doped V 2 O 5 thin films. The results showed a significant improvement in the transmittance and refractive index in TiO 2 doped V 2 O 5 thin films.
Scientific Reports, 2019
With the ever-increasing demand for low power electronics, neuromorphic computing has garnered hu... more With the ever-increasing demand for low power electronics, neuromorphic computing has garnered huge interest in recent times. Implementing neuromorphic computing in hardware will be a severe boost for applications involving complex processes such as image processing and pattern recognition. Artificial neurons form a critical part in neuromorphic circuits, and have been realized with complex complementary metal–oxide–semiconductor (CMOS) circuitry in the past. Recently, metal-insulator-transition materials have been used to realize artificial neurons. Although memristors have been implemented to realize synaptic behavior, not much work has been reported regarding the neuronal response achieved with these devices. In this work, we use the volatile threshold switching behavior of a vertical-MoS2/graphene van der Waals heterojunction system to produce the integrate-and-fire response of a neuron. We use large area chemical vapor deposited (CVD) graphene and MoS2, enabling large scale rea...
Materials Letters, 2018
Two-dimensional (2D) MoS 2 has recently emerged as an efficient hydrogen evolution reaction (HER)... more Two-dimensional (2D) MoS 2 has recently emerged as an efficient hydrogen evolution reaction (HER) catalyst due to its unique atomic layered structure and stability in harsh acidic environment. However, the high electrochemical performance of MoS 2 is still limited to edges of its 2D layers. Here, we report the synthesis of highly porous MoS 2 films exhibiting a large density of edge sites by using a direct sputter deposition method. Interestingly, the as-deposited MoS 2 films resulted into a 3R phase with nano porous structure which is attributed to the lattice relaxation and high energy of sputtered ions. The as-synthesized porous MoS 2 nanostructures demonstrate an excellent electrocatalytic performance with a low HER onset potential of 0.2V,long−termcyclingstability,andalowTafelslopeintherangeof0.2 V, long-term cycling stability, and a low Tafel slope in the range of 0.2V,long−termcyclingstability,andalowTafelslopeintherangeof80-90 mV/decade at a high cathodic current density.
Scientific reports, Jan 2, 2017
Two-dimensional molybdenum disulfide (2D MoS2) presents extraordinary optical, electrical, and ch... more Two-dimensional molybdenum disulfide (2D MoS2) presents extraordinary optical, electrical, and chemical properties which are highly tunable by engineering the orientation of constituent 2D layers. 2D MoS2 films with vertically-aligned layers exhibit numerous 2D edge sites which are predicted to offer superior chemical reactivity owing to their enriched dangling bonds. This enhanced chemical reactivity coupled with their tunable band gap energy can render the vertical 2D MoS2 unique opportunities for environmental applications that go beyond the conventional applications of horizontal 2D MoS2 in electronics/opto-electronics. Herein, we report that MoS2 films with vertically-aligned 2D layers exhibit excellent visible light responsive photocatalytic activities for efficiently degrading organic compounds in contaminated water such as harmful algal blooms. We demonstrate the visible light-driven rapid degradation of microcystin-LR, one of the most toxic compounds produced by the algal b...
Nano Letters, 2017
Two-dimensional (2D) transition metal dichalcogenides (TMDs) such as molybdenum or tungsten disul... more Two-dimensional (2D) transition metal dichalcogenides (TMDs) such as molybdenum or tungsten disulfides (MoS 2 or WS 2) exhibit extremely large in-plane strain limits and unusual optical/electrical properties, offering unprecedented opportunities for flexible
Advanced materials (Deerfield Beach, Fla.), Jan 28, 2017
The world is recently witnessing an explosive development of novel electronic and optoelectronic ... more The world is recently witnessing an explosive development of novel electronic and optoelectronic devices that demand more-reliable power sources that combine higher energy density and longer-term durability. Supercapacitors have become one of the most promising energy-storage systems, as they present multifold advantages of high power density, fast charging-discharging, and long cyclic stability. However, the intrinsically low energy density inherent to traditional supercapacitors severely limits their widespread applications, triggering researchers to explore new types of supercapacitors with improved performance. Asymmetric supercapacitors (ASCs) assembled using two dissimilar electrode materials offer a distinct advantage of wide operational voltage window, and thereby significantly enhance the energy density. Recent progress made in the field of ASCs is critically reviewed, with the main focus on an extensive survey of the materials developed for ASC electrodes, as well as cover...
Journal of Nanoscience and Nanotechnology, 2015
The present review explores an overall view of the vibration damping materials ranging from tradi... more The present review explores an overall view of the vibration damping materials ranging from traditionally used viscoelastic materials for macroscale damping to hybrid thin film heterostructures for micro-electro-mechanical systems (MEMS). Vibration damping materials like rubbers, polymers, metals, metal-matrix composites and smart materials are reviewed in terms of damping capacity, stiffness, mechanical strength and figure of merit. Nanoscale shape memory alloys, piezoelectric materials, carbon nanotubes, their composites and thin films are promising materials for future nanoscale damping devices. The main focus of this article is on our development of new vibration damping approach for MEMS structures comprising of ferroelastic/ferroelastic thin film heterostructures. For the first time, nanoindentation has been explored as an alternative tool to evaluate the damping capability of actual components (e.g., thin films for MEMS) where production of dynamic mechanical analyzer (DMA) test samples is not feasible. A comprehensive insight on the existing vibration damping materials and our new approach would definitely trigger some important applications in nano- and micro-electro-mechanical systems.
ACS Applied Materials & Interfaces, 2014
Two-dimensional MoS 2 is a promising material for next-generation electronic and optoelectronic d... more Two-dimensional MoS 2 is a promising material for next-generation electronic and optoelectronic devices due to its unique electrical and optical properties including the band gap modulation with film thickness. Although MoS 2 has shown excellent properties, wafer-scale production with layer control from single to few layers has yet to be demonstrated. The present study explored the large-scale and thicknessmodulated growth of atomically thin MoS 2 on Si/SiO 2 substrates using a two-step sputtering−CVD method. Our process exhibited wafer-scale fabrication and successful thickness modulation of MoS 2 layers from monolayer (0.72 nm) to multilayer (12.69 nm) with high uniformity. Electrical measurements on MoS 2 field effect transistors (FETs) revealed a p-type semiconductor behavior with much higher field effect mobility and current on/off ratio as compared to previously reported CVD grown MoS 2-FETs and amorphous silicon (a-Si) thin film transistors. Our results show that sputter−CVD is a viable method to synthesize large-area, high-quality, and layer-controlled MoS 2 that can be adapted in conventional Si-based microfabrication technology and future flexible, high-temperature, and radiation hard electronics/optoelectronics.
Handbook of Nanomaterials Properties, 2014
The present chapter explored the advancement of research in carbon nanomaterials (graphene and ca... more The present chapter explored the advancement of research in carbon nanomaterials (graphene and carbon nanotubes), in the areas of synthesis, properties and applications including electronics, field emission, biological and energy applications. The reported properties and applications of these carbon nanomaterials have opened up new opportunities for the future devices and materials. The knowledge presented here should lead to a better understanding of the key factors that can influence the future research directions.
Nanomaterials and Energy, 2015
In this study, the authors report on the structural and optical properties of vanadium pentoxide ... more In this study, the authors report on the structural and optical properties of vanadium pentoxide (V2O5) nanocrystalline thin films at different substrate temperatures ranging from room temperature to 450°C on glass substrates using vacuum evaporation technique. The deposition temperature was found to have significant effect on the structural, morphology and optical properties of these films. The X-ray diffraction pattern showed the formation of highly (001)-oriented, orthorhombic V2O5 films with high degree of crystallinity. Interestingly, field-emission scanning electron microscopy and atomic force microscopy analyses revealed the formation of uniformly distributed V2O5 nanorods (≈138 nm) at a deposition temperature of 350°C. A significant decrease in transmittance was observed in the V2O5 films deposited above 350°C, which could be attributed to the scattering light loss caused by the increase in surface roughness of the films at high deposition temperatures. The optical parameter...
International Journal of Clinical Trials, 2021
Background: Low backache (LBA) with lumbosacral radiculopathy is the most challenging musculoskel... more Background: Low backache (LBA) with lumbosacral radiculopathy is the most challenging musculoskeletal problem for its therapeutic management and cause of LBA with radiculopathy is a prolapsed disc. Epidural steroidal injection (ESI) are used in the management of the patients with sub-acute or chronic LBA with radiculopathy, not responding to conservative treatment. The most common cause being, lumbar disc disease, is confirmed via magnetic resonance imaging having high sensitivity and specificity. The aim of study was to check the efficacy of ESI in patients of sub-acute or chronic low backache with radiculopathy due to herniated disc.Methods: The study was conducted over 200 patients reporting our OPD during Dec 2017- Feb 2018 with complaints of LBA with radiculopathy, not responding to conservative treatment. Maximum of 3 ESI were given with two weeks of interval in between. The patients were assessed using VAS scoring system.Results: 77.5% patients got improvement in symptoms, a...
The community-developed, free and open-source solar data analysis environment for Python.
Saudi Journal of Anaesthesia, 2021
As the motivation to potentially allow for a more expansive role of opioid-sparing anaesthesia in... more As the motivation to potentially allow for a more expansive role of opioid-sparing anaesthesia in various surgical specialities transpire with new zeal, promising evidence needs to be accumulated to substantiate the same. Appropriate to this context, the index case series highlight the beneficial effects of an intraoperative magnesium sulphate infusion on perioperative hemodynamic profile and postoperative recovery in patients undergoing intracranial cerebral aneurysm surgery.
physica status solidi (RRL) – Rapid Research Letters, 2021
Harnessing the recently discovered ferroelectricity in scandium aluminum nitride (ScxAl1−xN) for ... more Harnessing the recently discovered ferroelectricity in scandium aluminum nitride (ScxAl1−xN) for the realization of integrated electronic and electromechanical devices requires a low‐temperature growth process that enables versatile control over film thickness, stoichiometric composition, and stress. Herein, a reactive magnetron sputtering process that enables extreme scaling of film thickness and tuning of composition and residual stress is reported on. Highly crystalline ScxAl1−xN films with thicknesses of over 25–250 nm with scandium concentrations of over 22–30 at% are sputtered using a segmented target created from scandium and aluminum tiles. The residual stress in the films is widely tuned from highly compressive to tensile using a pressure‐ and gas‐flow‐independent approach based on adjusting the electrical termination of the targets. The crystallinity, texture, and ferroelectric characteristics are measured for ScxAl1−xN films with different thicknesses, compositions, and residual stresses. The results highlight the consistent crystallinity and ferroelectric properties despite extreme thickness miniaturization to sub‐50 nm, and the large dependence of the coercive field on the residual stress and Sc concentration.
IEEE Electron Device Letters, 2021
This letter reports intrinsically switchable ultra- and super-high-frequency Lamb-mode resonators... more This letter reports intrinsically switchable ultra- and super-high-frequency Lamb-mode resonators based on the use of ferroelectricity in scandium aluminum nitride (Sc<sub>x</sub>Al<sub>1−x</sub>N) films. Highly crystalline 200nm-thick Sc<sub>0.22</sub>Al<sub>0.78</sub>N film is sputtered using segmented-target reactive magnetron sputtering, and interdigitated electrodes are patterned to create one-port resonators operating in symmetric Lamb modes. The resonators are intrinsically switched using the ferroelectric behavior in Sc<sub>0.22</sub>Al<sub>0.78</sub>N film and through polarization switching at one of the terminals, resulting in a zero-sum electromechanical coupling factor (<inline-formula> <tex-math notation="LaTeX">${k}_{t}^{2}$ </tex-math></inline-formula>). Resonators with frequencies over 0.45 – 6 GHz, frequency <inline-formula> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> quality factor product (<inline-formula> <tex-math notation="LaTeX">${f}_{s}\times {Q}$ </tex-math></inline-formula>) as high as <inline-formula> <tex-math notation="LaTeX">$4\times 10^{12}$ </tex-math></inline-formula>, and and <inline-formula> <tex-math notation="LaTeX">$k_{t}^{2} \times Q$ </tex-math></inline-formula> product exceeding29 aredemonstrated. The intrinsic switchability of resonators is characterized using 100ms triangular monopolar pulses, resulting in an admittance switching isolation as high as 15dB.
International Journal of Research in Orthopaedics, 2020
Background: Fractures of the lateral condyle of the humerus in children are common injuries. If d... more Background: Fractures of the lateral condyle of the humerus in children are common injuries. If displaced or unstable they may require surgical reduction and fixation with Kirschner wires (K-wires). These may be passed through the skin and left exposed or buried subcutaneously.Methods: A prospective study was carried out in department of orthopaedics at my college from January 2019 to March 2020. A total number of 37 subjects were included in the study.Results: Patients were followed for a period of 3 months and results were drawn on basis of union, infection, carrying angle at the elbow, and range of motion (ROM) which was assessed by clinico-radiological means.Conclusions: Buried wire group has shown better union rate than exposed group, wires could be removed under local anaesthesia thereby avoiding any major procedure and also the risk of infection is low making this a better option than the exposed cohort.
Indian Journal of Clinical Anaesthesia, 2020
Large retrosternal goitre is a challenge to the anaesthesiologist and the surgeon. We describe th... more Large retrosternal goitre is a challenge to the anaesthesiologist and the surgeon. We describe the successful anaesthetic management of a 44 year old male patient with extensive retrosternal goitre with severe tracheal compression, operated for total thyroidectomy under general anaesthesia by combined cervical approach and sternotomy. A multidisciplinary team approach with surgical colleagues allowed successful management of the patient.
Indian Journal of Clinical Anaesthesia, 2020
Introduction: Central venous line placement is one of the essential procedures in the treatment o... more Introduction: Central venous line placement is one of the essential procedures in the treatment of critically ill patients admitted in the intensive care unit. Central venous catheterization is required not only for providing a route for delivery of the caustic or critical medications but it also allows for the measurement of central venous pressure. Being an invasive procedure it has a learning curve and is associated with many complications. Hence, we conducted the study comparing catheterization of internal jugular vein by ultrasound guided versus landmark approach, with respect to the ease of insertion and related complications in Intensive Care Unit (I.C.U.) patients. Materials and Methods: 150 patients admitted in the I.C.U, fulfilling the inclusion criteria were divided into two groups based on computer generated randomization table namely: group A (landmark technique) and group B (USG technique) comprising of 75 patients in each group. In landmark approach, the internal jugular vein was located at the apex of triangle formed by the sterna and clavicular heads of sternocleidomastoid muscle and needle was directed towards the ipsilateral nipple when advanced through skin, lateral to the carotid artery pulsations with artery being pushed medially. In USG guided approach, the linear USG probe of 7 MHz connected to a real-time Kontron Medical ultrasound unit, was used with standard two-dimensional (2D) ultrasound imaging to identify the IJV. Catheterization was performed real-time by placing the transducer of the ultrasound parallel and superior to clavicle, over the groove between the two heads of the sternocleidomastoid muscle (SAX view). A postprocedure x-ray of chest was done as early as possible to assess the placement of CVC and rule out any complication. Results: The two groups were comparable in age, sex and body mass index. There was no statistically significant difference in the mean number of attempts taken for catheterization of IJV between the two groups (p-value=0.124). However, the mean time taken for cannulation of IJV was found to be significantly lower in the USG group as compared to the landmark group (p-value=0.03). The overall rate of complications was significantly higher in group A (p=0.012). Conclusion: Ultrasonography guidance significantly reduced the total procedural time and the rate of complications during internal jugular vein cannulation compared to the landmark technique.
International Journal of Research in Medical Sciences, 2020
Background: COVID-19 pandemic effects are still being elucidated. Stay-at-home orders issued duri... more Background: COVID-19 pandemic effects are still being elucidated. Stay-at-home orders issued during peak of COVID-19 and social distancing as lockdown measures compounded with COVID-19 concerns have caused significant disruptions in daily life. One notable effect of these variables may be a change in the number of emergency department (ED) visits. This study aims to investigate the effects of COVID-19 on ED visits, and possible reasons for changes.Methods: Retrospective analysis using data for ED visits and procedures performed in the orthopaedics department of GMC Jammu were collected from the record section of GMC Jammu for four months prior and post implementation of lockdown and results were deduced with regards to the comparison in the number of visits, admissions and surgeries done pre and post-lockdown period.Results: The mean number of ED visits/admissions per day for the last four months of available data post lockdown due to COVID-19 pandemic was significantly less than th...
Applied Physics Letters, 2019
Emulating the human brain's circuitry composed of neurons and synapses is an emerging area of... more Emulating the human brain's circuitry composed of neurons and synapses is an emerging area of research in mitigating the “von Neumann bottleneck” in present computer architectures. The building block of these neuromorphic systems—the synapse—is commonly realized with oxide-based or phase change material-based devices, whose operation is limited by high programming currents and high reset currents. In this work, we have realized nonvolatile resistive switching MoS2/graphene devices that exhibit multiple conductance states at low operating currents. The MoS2/graphene devices exhibit essential synaptic behaviors, such as short and long-term potentiation, long-term depression, and the spike timing dependent plasticity learning rule. Most importantly, they exhibit a near-linear synaptic weight update, without any abrupt reset process, allowing their use in unsupervised learning applications. These electronic synapses are built with chemical vapor deposited MoS2 and graphene, demonstr...
Madridge Journal of Nanotechnology & Nanoscience, 2018
We studied the influence of titanium dioxide (TiO 2) concentration on the structural and optical ... more We studied the influence of titanium dioxide (TiO 2) concentration on the structural and optical properties of vanadium pentoxide (V 2 O 5) thin films deposited on amorphous glass substrate using pulsed laser deposition technique. TiO 2 doping into V 2 O 5 matrix revealed an interesting morphological change from an array of high density pure V 2 O 5 nanorods (~140 nm) to granular structure inTiO 2-doped V 2 O 5 thin films. The results showed a significant improvement in the transmittance and refractive index in TiO 2 doped V 2 O 5 thin films.
Scientific Reports, 2019
With the ever-increasing demand for low power electronics, neuromorphic computing has garnered hu... more With the ever-increasing demand for low power electronics, neuromorphic computing has garnered huge interest in recent times. Implementing neuromorphic computing in hardware will be a severe boost for applications involving complex processes such as image processing and pattern recognition. Artificial neurons form a critical part in neuromorphic circuits, and have been realized with complex complementary metal–oxide–semiconductor (CMOS) circuitry in the past. Recently, metal-insulator-transition materials have been used to realize artificial neurons. Although memristors have been implemented to realize synaptic behavior, not much work has been reported regarding the neuronal response achieved with these devices. In this work, we use the volatile threshold switching behavior of a vertical-MoS2/graphene van der Waals heterojunction system to produce the integrate-and-fire response of a neuron. We use large area chemical vapor deposited (CVD) graphene and MoS2, enabling large scale rea...
Materials Letters, 2018
Two-dimensional (2D) MoS 2 has recently emerged as an efficient hydrogen evolution reaction (HER)... more Two-dimensional (2D) MoS 2 has recently emerged as an efficient hydrogen evolution reaction (HER) catalyst due to its unique atomic layered structure and stability in harsh acidic environment. However, the high electrochemical performance of MoS 2 is still limited to edges of its 2D layers. Here, we report the synthesis of highly porous MoS 2 films exhibiting a large density of edge sites by using a direct sputter deposition method. Interestingly, the as-deposited MoS 2 films resulted into a 3R phase with nano porous structure which is attributed to the lattice relaxation and high energy of sputtered ions. The as-synthesized porous MoS 2 nanostructures demonstrate an excellent electrocatalytic performance with a low HER onset potential of 0.2V,long−termcyclingstability,andalowTafelslopeintherangeof0.2 V, long-term cycling stability, and a low Tafel slope in the range of 0.2V,long−termcyclingstability,andalowTafelslopeintherangeof80-90 mV/decade at a high cathodic current density.
Scientific reports, Jan 2, 2017
Two-dimensional molybdenum disulfide (2D MoS2) presents extraordinary optical, electrical, and ch... more Two-dimensional molybdenum disulfide (2D MoS2) presents extraordinary optical, electrical, and chemical properties which are highly tunable by engineering the orientation of constituent 2D layers. 2D MoS2 films with vertically-aligned layers exhibit numerous 2D edge sites which are predicted to offer superior chemical reactivity owing to their enriched dangling bonds. This enhanced chemical reactivity coupled with their tunable band gap energy can render the vertical 2D MoS2 unique opportunities for environmental applications that go beyond the conventional applications of horizontal 2D MoS2 in electronics/opto-electronics. Herein, we report that MoS2 films with vertically-aligned 2D layers exhibit excellent visible light responsive photocatalytic activities for efficiently degrading organic compounds in contaminated water such as harmful algal blooms. We demonstrate the visible light-driven rapid degradation of microcystin-LR, one of the most toxic compounds produced by the algal b...
Nano Letters, 2017
Two-dimensional (2D) transition metal dichalcogenides (TMDs) such as molybdenum or tungsten disul... more Two-dimensional (2D) transition metal dichalcogenides (TMDs) such as molybdenum or tungsten disulfides (MoS 2 or WS 2) exhibit extremely large in-plane strain limits and unusual optical/electrical properties, offering unprecedented opportunities for flexible
Advanced materials (Deerfield Beach, Fla.), Jan 28, 2017
The world is recently witnessing an explosive development of novel electronic and optoelectronic ... more The world is recently witnessing an explosive development of novel electronic and optoelectronic devices that demand more-reliable power sources that combine higher energy density and longer-term durability. Supercapacitors have become one of the most promising energy-storage systems, as they present multifold advantages of high power density, fast charging-discharging, and long cyclic stability. However, the intrinsically low energy density inherent to traditional supercapacitors severely limits their widespread applications, triggering researchers to explore new types of supercapacitors with improved performance. Asymmetric supercapacitors (ASCs) assembled using two dissimilar electrode materials offer a distinct advantage of wide operational voltage window, and thereby significantly enhance the energy density. Recent progress made in the field of ASCs is critically reviewed, with the main focus on an extensive survey of the materials developed for ASC electrodes, as well as cover...
Journal of Nanoscience and Nanotechnology, 2015
The present review explores an overall view of the vibration damping materials ranging from tradi... more The present review explores an overall view of the vibration damping materials ranging from traditionally used viscoelastic materials for macroscale damping to hybrid thin film heterostructures for micro-electro-mechanical systems (MEMS). Vibration damping materials like rubbers, polymers, metals, metal-matrix composites and smart materials are reviewed in terms of damping capacity, stiffness, mechanical strength and figure of merit. Nanoscale shape memory alloys, piezoelectric materials, carbon nanotubes, their composites and thin films are promising materials for future nanoscale damping devices. The main focus of this article is on our development of new vibration damping approach for MEMS structures comprising of ferroelastic/ferroelastic thin film heterostructures. For the first time, nanoindentation has been explored as an alternative tool to evaluate the damping capability of actual components (e.g., thin films for MEMS) where production of dynamic mechanical analyzer (DMA) test samples is not feasible. A comprehensive insight on the existing vibration damping materials and our new approach would definitely trigger some important applications in nano- and micro-electro-mechanical systems.
ACS Applied Materials & Interfaces, 2014
Two-dimensional MoS 2 is a promising material for next-generation electronic and optoelectronic d... more Two-dimensional MoS 2 is a promising material for next-generation electronic and optoelectronic devices due to its unique electrical and optical properties including the band gap modulation with film thickness. Although MoS 2 has shown excellent properties, wafer-scale production with layer control from single to few layers has yet to be demonstrated. The present study explored the large-scale and thicknessmodulated growth of atomically thin MoS 2 on Si/SiO 2 substrates using a two-step sputtering−CVD method. Our process exhibited wafer-scale fabrication and successful thickness modulation of MoS 2 layers from monolayer (0.72 nm) to multilayer (12.69 nm) with high uniformity. Electrical measurements on MoS 2 field effect transistors (FETs) revealed a p-type semiconductor behavior with much higher field effect mobility and current on/off ratio as compared to previously reported CVD grown MoS 2-FETs and amorphous silicon (a-Si) thin film transistors. Our results show that sputter−CVD is a viable method to synthesize large-area, high-quality, and layer-controlled MoS 2 that can be adapted in conventional Si-based microfabrication technology and future flexible, high-temperature, and radiation hard electronics/optoelectronics.
Handbook of Nanomaterials Properties, 2014
The present chapter explored the advancement of research in carbon nanomaterials (graphene and ca... more The present chapter explored the advancement of research in carbon nanomaterials (graphene and carbon nanotubes), in the areas of synthesis, properties and applications including electronics, field emission, biological and energy applications. The reported properties and applications of these carbon nanomaterials have opened up new opportunities for the future devices and materials. The knowledge presented here should lead to a better understanding of the key factors that can influence the future research directions.
Nanomaterials and Energy, 2015
In this study, the authors report on the structural and optical properties of vanadium pentoxide ... more In this study, the authors report on the structural and optical properties of vanadium pentoxide (V2O5) nanocrystalline thin films at different substrate temperatures ranging from room temperature to 450°C on glass substrates using vacuum evaporation technique. The deposition temperature was found to have significant effect on the structural, morphology and optical properties of these films. The X-ray diffraction pattern showed the formation of highly (001)-oriented, orthorhombic V2O5 films with high degree of crystallinity. Interestingly, field-emission scanning electron microscopy and atomic force microscopy analyses revealed the formation of uniformly distributed V2O5 nanorods (≈138 nm) at a deposition temperature of 350°C. A significant decrease in transmittance was observed in the V2O5 films deposited above 350°C, which could be attributed to the scattering light loss caused by the increase in surface roughness of the films at high deposition temperatures. The optical parameter...