20 research outputs found

    MICROWAVE RADIATIONS FOR HEAT-SETTING OF POLYESTER FIBERS

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    The use of radio and microwave frequency is gainingimportance for industrial applications such asheating, drying, and other processing. The mostimportant advantage of using microwave is that it isnon-contact or localized heating and the heat isproduced within the material. This can be much moreeffective than indirect heating where the heatpropagation is by heat conduction through thematerial. We have been investigating the influence ofmicrowave radiation on different fibers for the lastfew years. In the present investigation we usedmicrowave frequency of 2450 MHz to investigate itseffect on polyester fibers. The polyester fibers wereheat set in air as well as a liquid, which acted as alossy substances. The liquid was chosen on the basisof earlier experiments, which showed the maximumeffect. A comparative study was also carried outusing conventional heating in silicone oil.Using the method of X-ray Diffraction (XRD) wecalculated the changes in % crystallinity andorientation. It was found that as the time of treatmentunder microwave radiation increased from 15 sec. to120 sec. the order factor was found to increase from0.32 to 0.71.The crystalline orientation as determinedfrom the azimuthal scan was also found to increase.Such structural changes can be highly beneficial forthe processing of fabric in industry. The microwaveradiation process is fast, reliable and energy saving

    Relationship of incidence of anterior cruciate ligament injuries and body-built Index somatotype in Indian population

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    Background: Incidence of ACL injuries and physical parameters like age, sex, height, weight and BMI has been studied intensely as a risk factor. Each of them poses as a different risk factor for occurrence of ACL injuries. But body-built index-somatotype considers relative proportions of fatness, muscle mass and skeletal architecture in terms of endomorphy, mesomorphy and ectomorphy in a single individual which neutralises variables like age, sex, BMI. Methods: 100 patients were included in the study, excluding those with multiligament injuries, associated fractures around knee, mucoid degeneration of ACL and road traffic accident cases. Parameters such as skin fold thickness, circumference and epicondylar, condylar width was taken into consideration. Body built index was calculated in terms of endomorphy, mesomorphy and ectomorphy using the heath-carter anthropometric somatotype manual. Results: We found that amongst all those have ACL injury, endomorphy was higher grade (5.49), followed by mesomorphy (4.75). Lesser grades of ectomorphs i.e., slender people were having ACL injuries. Though there was low margin of grading between the two, endomorphy was higher in ACL injured people followed by mesomorphy. Conclusions: Endomorphs and mesomorphs have higher tendancy of ACL injury. Ectomorphs have lesser incidence of ACL injury

    Developmental Changes in the ECG of a Hamster Model of Muscular Dystrophy and Heart Failure

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    Aberrant autonomic signaling is being increasingly recognized as an important symptom in neuromuscular disorders. The δ-sarcoglycan-deficient BIO TO-2 hamster is recognized as a good model for studying mechanistic pathways and sequelae in muscular dystrophy and heart failure, including autonomic nervous system (ANS) dysfunction. Recent studies using the TO-2 hamster model have provided promising preclinical results demonstrating the efficacy of gene therapy to treat skeletal muscle weakness and heart failure. Methods to accelerate preclinical testing of gene therapy and new drugs for neuromuscular diseases are urgently needed. The purpose of this investigation was to demonstrate a rapid non-invasive screen for characterizing the ANS imbalance in dystrophic TO-2 hamsters. Electrocardiograms were recorded non-invasively in conscious ∼9-month old TO-2 hamsters (n = 10) and non-myopathic F1B control hamsters (n = 10). Heart rate was higher in TO-2 hamsters than controls (453 ± 12 bpm vs. 311 ± 25 bpm, P < 0.01). Time domain heart rate variability, an index of parasympathetic tone, was lower in TO-2 hamsters (12.2 ± 3.7 bpm vs. 38.2 ± 6.8, P < 0.05), as was the coefficient of variance of the RR interval (2.8 ± 0.9% vs. 16.2 ± 3.4%, P < 0.05) compared to control hamsters. Power spectral analysis demonstrated reduced high frequency and low frequency contributions, indicating autonomic imbalance with increased sympathetic tone and decreased parasympathetic tone in dystrophic TO-2 hamsters. Similar observations in newborn hamsters indicate autonomic nervous dysfunction may occur quite early in life in neuromuscular diseases. Our findings of autonomic abnormalities in newborn hamsters with a mutation in the δ-sarcoglycan gene suggest approaches to correct modulation of the heart rate as prevention or therapy for muscular dystrophies

    Gait dynamics in mouse models of Parkinson's disease and Huntington's disease

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    BACKGROUND: Gait is impaired in patients with Parkinson's disease (PD) and Huntington's disease (HD), but gait dynamics in mouse models of PD and HD have not been described. Here we quantified temporal and spatial indices of gait dynamics in a mouse model of PD and a mouse model of HD. METHODS: Gait indices were obtained in C57BL/6J mice treated with the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg/day for 3 days) for PD, the mitochondrial toxin 3-nitropropionic acid (3NP, 75 mg/kg cumulative dose) for HD, or saline. We applied ventral plane videography to generate digital paw prints from which indices of gait and gait variability were determined. Mice walked on a transparent treadmill belt at a speed of 34 cm/s after treatments. RESULTS: Stride length was significantly shorter in MPTP-treated mice (6.6 ± 0.1 cm vs. 7.1 ± 0.1 cm, P < 0.05) and stride frequency was significantly increased (5.4 ± 0.1 Hz vs. 5.0 ± 0.1 Hz, P < 0.05) after 3 administrations of MPTP, compared to saline-treated mice. The inability of some mice treated with 3NP to exhibit coordinated gait was due to hind limb failure while forelimb gait dynamics remained intact. Stride-to-stride variability was significantly increased in MPTP-treated and 3NP-treated mice compared to saline-treated mice. To determine if gait disturbances due to MPTP and 3NP, drugs affecting the basal ganglia, were comparable to gait disturbances associated with motor neuron diseases, we also studied gait dynamics in a mouse model of amyotrophic lateral sclerosis (ALS). Gait variability was not increased in the SOD1 G93A transgenic model of ALS compared to wild-type control mice. CONCLUSION: The distinct characteristics of gait and gait variability in the MPTP model of Parkinson's disease and the 3NP model of Huntington's disease may reflect impairment of specific neural pathways involved

    Gait Disturbances in Dystrophic Hamsters

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    The delta-sarcoglycan-deficient hamster is an excellent model to study muscular dystrophy. Gait disturbances, important clinically, have not been described in this animal model. We applied ventral plane videography (DigiGait) to analyze gait in BIO TO-2 dystrophic and BIO F1B control hamsters walking on a transparent treadmill belt. Stride length was ∼13% shorter (P < .05) in TO-2 hamsters at 9 months of age compared to F1B hamsters. Hindlimb propulsion duration, an indicator of muscle strength, was shorter in 9-month-old TO-2 (247 ± 8 ms) compared to F1B hamsters (272 ± 11 ms; P < .05). Braking duration, reflecting generation of ground reaction forces, was delayed in 9-month-old TO-2 (147 ± 6 ms) compared to F1B hamsters (126 ± 8 ms; P < .05). Hindpaw eversion, evidence of muscle weakness, was greater in 9-month-old TO-2 than in F1B hamsters (17.7 ± 1.2° versus 8.7 ± 1.6°; P < .05). Incline and decline walking aggravated gait disturbances in TO-2 hamsters at 3 months of age. Several gait deficits were apparent in TO-2 hamsters at 1 month of age. Quantitative gait analysis demonstrates that dystrophic TO-2 hamsters recapitulate functional aspects of human muscular dystrophy. Early detection of gait abnormalities in a convenient animal model may accelerate the development of therapies for muscular dystrophy

    Thermodynamic study of combining chemical looping combustion and combined reforming of propane

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    Existing energy generation technologies emit CO2 gas and are posing a serious problem of global warming and climate change. The thermodynamic feasibility of a new process scheme combining chemical looping combustion (CLC) and combined reforming (CR) of propane (LPG) is studied in this paper. The study of CLC of propane with CaSO4 as oxygen carrier shows thermodynamic feasibility in temperature range (400-782.95 &#176; C) at 1 bar pressure. The CO2 generated in the CLC can be used for combined reforming of propane in an autothermal way within the temperature range (400-1000 &#176; C) at 1 bar pressure to generate syngas of ratio 3.0 (above 600 &#176; C) which is extremely desirable for petrochemical manufacture. The process scheme generates (a) huge thermal energy in CLC that can be used for various processes, (b) pure N2 and syngas rich streams can be used for petrochemical manufacture and (c) takes care of the expensive CO2 separation from flue gas stream and CO2 sequestration. The thermoneutral temperature (TNP) of 702.12 &#176; C yielding maximum syngas of 5.98 mol per mole propane fed, of syngas ratio 1.73 with negligible methane and carbon formation was identified as the best condition for the CR reactor operation. The process can be used for different fuels and oxygen carriers

    Regioselectivity Switch Achieved in the Palladium Catalyzed α-Arylation of Enones by Employing the Modified Kuwajima–Urabe Conditions

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    A new regioselective approach to the synthesis of α-aryl enones is reported. This represents an important application of the Kuwajima–Urabe protocol toward the synthesis of this simple albeit complex functional array. Several α-aryl enones were synthesized by the palladium catalyzed arylation of triethylsilylenol ethers of enones with high regioselectivity and broad scope, utilizing sterically encumbered electron-rich phosphine ligands to drive the reaction

    Melanotic neuroectodermal tumor of infancy: Report of a case associated with high urinary excretion of Vanilmandelic acid

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    Melanotic neuroectodermal tumor of infancy is a rare congenital neoplasm involving the head and neck region in young patients. A case of melanotic neuroectodermal tumor of infancy is presented. This tumor occurred in right maxillary alveolar ridge in a 4-month-old infant. The present case showed an increased urinary level of vanilmandelic acid, confirming that the tumor is originated from neural crest. Clinical assessment, histologic diagnosis, and laboratory findings supported the diagnosis
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