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In this work, we demonstrated the supercapacitor performance of pristine and composites of spinel NiCo2O4 with a multi-walled carbon nanotube (MWCNT) assembled in a two-electrode cell configuration. Spinel NiCo2O4 and NiCo2O4@MWCNT composites were synthesized via a facile hydrothermal method. The supercapacitive performance of as-synthesized NiCo2O4 and NiCo2O4@MWCNT fabricated on Ni-foam was studied in a 0.5M K2SO4 electrolyte using electrochemical measurement techniques. The symmetric cell configuration of NiCo2O4@MWCNT delivers high specific capacitance (374 F/g at 2 A/g) with high energy density and power density (95 Wh/kg and 3 964 W/kg, respectively) compared to that of pristine NiCo2O4 electrodes (137 F/g at 0.6 A/g). Furthermore, the energy storage performance of the asymmetric cells of NiCo2O4//MWCNT and NiCo2O4@MWCNT//MWCNT was studied to enhance cycling stability (retention of 74.85% over 3000 cycles). We have also theoretically studied the supercapacitance performance of pristine NiCo2O4 and NiCo2O4@SWCNT hybrid structures through its structural and electronic properties using density functional theory predictions. The higher specific capacitance of the NiCo2O4@SWCNT hybrid system with high power density and energy density is supported by the enhanced density of states near the Fermi level and increased quantum capacitance of the hybrid structure. We have theoretically computed the diffusion energy barrier of K+ ions of the K2SO4 electrolyte in the NiCo2O4 layer and compared it with the diffusion barrier for Na+ ions. The lesser diffusion energy barrier for K+ ions in the NiCo2O4 layer contributes toward higher energy storage capacity. Thus, owing to superior electrochemical performance of NiCo2O4 composites with MWCNTs, it can serve as a high-performance electrode material for supercapacitor applications.
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OBJECTIVE: The use of hand held devices (HHD) such as mobile phones, game controls, tablets, portable media players and personal digital assistants have increased dramatically in past decade. While sending a text message or using the controls of the HHD the users need to use their thumb and other palm muscles extensively. The objective of this study was to describe the risk factors and clinical features of the musculoskeletal disorders (MSDs) arising due to usage of hand held devices and to evaluate the effectiveness of a sequenced rehabilitation protocol. METHODS: A retrospective report analysis of 70 subjects, who were diagnosed to have a MSD affecting the upper extremities, was conducted. Medical charts from a tertiary level rehabilitation centre from 2005-2013 were analysed. All the subjects reported pain in their upper extremities following extensive usage of HHD and were examined and diagnosed to have a MSD by an orthopaedic and rehabilitation physician. After the assessment and diagnosis, all the patients underwent rehabilitation using a sequenced protocol. RESULTS: All the subjects reported pain in the thumb and forearm with associated burning, numbness and tingling around the thenar aspect of the hand, and stiffness of wrist and hand. 43 subjects had symptoms on the right side; 9 on left and 18 had bilateral symptoms. Correlation was found between hand dominance and MSD. 33 subjects complained of onset of symptoms following extensive text messaging. All the subjects were diagnosed to have tendinosis of Extensor Pollicis Longus and Myofascial Pain Syndrome affecting the 1st interossei, thenar group of muscles and Extensor Digitorum Communis. 23 of the subjects were senior executives, among these 7 were CEO's of major multinational companies in India. All the subjects recovered completely following the rehabilitation. CONCLUSIONS: The study concluded that mobile phones and gadgets that promoted the predominant usage of thumb or only one finger while texting or using the controls were associated with a higher prevalence of MSDs. Treatment using a sequenced rehabilitation protocol was found to be effective.
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OBJECTIVES: The objective of this study was to identify the musculoskeletal co-morbidities of neck pain of myofascial origin among IT professionals. METHODS: A retrospective report analysis of 5357 IT professionals from various IT companies in India was conducted. Demographic details, type and intensity of the musculoskeletal problems, employee feedbacks on status of musculoskeletal health and physician's diagnosis were analysed. Descriptive statistics were used to describe the age, gender, body area affected and nature of work. Chi square test was used to find the association between musculoskeletal co-morbidities and myofascial neck pain (MNP). RESULTS: The study participants were predominantly males (71%). 41% of the population used laptops, 35% desktops and 24% both. Neck pain was the commonest reported symptom, followed by low back, shoulder and arm pain respectively. Statistical analysis also revealed that low back pain and shoulder pain, had a significant association with neck pain. Further analysis revealed that there was a significant association between the presence of MNP and thoracic outlet syndrome (p < 0.001) and fibromyalgia syndrome (p < 0.001). Other than the listed co-morbidities, eye strain was also found to be associated with MNP. CONCLUSIONS: Low back pain and shoulder pain was found to be co morbid symptoms noted among IT professionals with MNP. Thoracic outlet syndrome and fibromyalgia were found to be the most commonly associated disorders with MNP among IT professionals.
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Workrelated musculoskeletal disorders among the IT professional is a common area of concern worldwide. This study was taken up to analyze the prevalence of risk factors, clinical features and outcome of treatment in onsite clinics in vaious information technology companies in India. Result revealed poor office ergonomics (54%), lack of keyboard tray (25%), lack of mouse tray (35%), lack of foot rest (60%), improper monitor height (80%) were the major self reported risk factors. Major identified MSD were Myofascial Pain Syndrome (49.20%), Thoracic outlet syndrome (25.02%), Fibromyalgia syndrome (8.5%). Majorly affected body regions were neck (64.9%), shoulder (42.1%), lower back (56.5%) and thigh (34.2%). The results were comparable with the literature. Feedback of the participants also revealed most of the participants were well satisfied with SHARAN's protocol.
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Enfermedades Musculoesqueléticas/etiología , Enfermedades Profesionales/etiología , Servicios de Salud del Trabajador , Adulto , Terminales de Computador , Ergonomía , Humanos , India , Enfermedades Musculoesqueléticas/diagnóstico , Enfermedades Musculoesqueléticas/terapia , Estudios Retrospectivos , Factores de Riesgo , Tecnología , Adulto JovenRESUMEN
INTRODUCTION: Work-related musculoskeletal disorders are common in computer professionals. Workstyle may be one of the risk factors in the development of musculoskeletal discomfort. The objective of this retrospective study was to examine the prevalence of adverse workstyle in computer professionals from India and to evaluate if workstyle factors were predictors of pain and loss of productivity. METHODS: Office workers from various information technology (IT) companies in India responded to the short-form workstyle questionnaire and pain questionnaire. Correlation analyses were conducted to examine the associations between different variables followed by a multivariate logistic regression to understand the unique predictors of pain and loss of productivity. RESULTS: 4,500 participants responded to the workstyle and pain questionnaire. 22% of participants were reported to have a high risk of an adverse workstyle. 63% of participants reported pain symptoms. Social reactivity, lack of breaks, and deadlines/pressure subscales of workstyle questionnaire were significantly correlated with pain and loss of productivity. Regression analyses revealed that workstyle factors and duration of computer use per day were significant predictors of pain. CONCLUSION: Workstyle seems to be a mediating factor for musculoskeletal pain, discomfort, and loss of productivity. Based on the study findings, it is recommended that intervention efforts directed towards prevention of musculoskeletal disorders should focus on psychosocial work factors such adverse workstyle in addition to biomechanical risk factors.