Transpiration Cooling System in Al-Co Open-celled Foam having PPI of 13

One-dimensional transpiration cooling system in open-celled foam has been conducted experimentally and numerically to investigate the heat transfer characteristics of combined convection and radiation. The Alumina–Cordierite (Al-Co) open-cell foam having porosity of 0.87 and pores per inch (PPI) of 13 was employed. The upper surface of porous plate was heated by the heat flux of incoming radiation (qRx,f) varying from 0.97 - 16.59 kW/m2 whereas air injection velocity (uf) fed into the lower surface was varied from 0.364 - 1.274 m/s, and then uf was converted as Reynolds number (Re). The results show that the temperature efficiency (hT), indicating how close the mean temperature of a porous heat plate to that of inlet air, increased rapidly with the air injection velocity (Re). It was then saturated and had a constant value at Re higher than 30. The conversion efficiency (hC), which was regarded as the ability of porous material in transferring energy by convection after absorbed from heat radiation, decreased slightly with increasing of qRx,f and uf (Re). The numerical predictions also agreed well with experimental data. Keyword: Open-cell foam, Radiation, Transpiration cooling, Reynolds numbe

CFD modelling of a two-phase closed thermosyphon charged with R134a and R404a

This paper examines the application of CFD modelling to simulate the two-phase heat transfer mechanisms in a wickless heat pipe, also called a thermosyphon. Two refrigerants, R134a and R404a, were selected as the working fluids of the investigated thermosyphon. A CFD model was built to simulate the details of the two-phase flow and heat transfer phenomena during the start-up and steady-state operation of the thermosyphon. The CFD simulation results were compared with experimental measurements, with good agreement obtained between predicted temperature profiles and experimental temperature data, thus confirming that the CFD model was successful in reproducing the heat and mass transfer processes in the R134a and R404a charged thermosyphon, including the pool boiling in the evaporator section and the liquid film in the condenser section

Transpiration Cooling System using Open-cellular Alumina-Cordierite Porous Media having Pore Per Inches (PPI) of 6.0

AbstractAnalysis of numerical model and experimental study on steady-state heat transfer characteristics of combinedconvection and radiation of the air transpiration cooling system using the open-cellular porous material was investigated.The Alumina-Cordierite (Al-Co) open - cellular plates, having porosity of 0.873 and pores per inch (PPI) of 6.0, was usedas porous media. The upper surface of porous plate was heated by the heat flux (qR) of incoming radiation varying from0.988 to 16.560 kW/m2 whereas air injection velocity fed into the lower surface was varied from 0.212 to 1.486 m/s. Toreport the results in the paper, the air velocity was rearranged as Reynolds number (Re). From study, the results showedthat the temperature profile of both gas and solid phase increased when qR, increased and Re decreased. The temperature efficiency (ηT) increased first and then was taken to constant level about of 97% for Re > 70. The conversion efficiency (ηC) increased slightly with Re but depend strongly with qR. The agreement between theoretical and experiential data wassatisfactory

Assessing Walking Ability in People with HTLV-1-Associated Myelopathy Using the 10 Meter Timed Walk and the 6 Minute Walk Test

Five to ten million persons, are infected by HTLV-1 of which 3% will develop HTLV-1-associated myelopathy (HAM) a chronic, disabling inflammation of the spinal cord. Walking, a fundamental, complex, multi-functional task is demanding of multiple body systems. Restricted walking ability compromises activity and participation levels in people with HAM (pwHAM). Therapy aims to improve mobility but validated measures are required to assess change.Prospective observational study.To explore walking capacity in pwHAM, walking endurance using the 6 minute walk (6MW), and gait speed, using the timed 10m walk (10mTW).Out-patient setting in an inner London Teaching hospital.Prospective documentation of 10mTW and 6MW distance; walking aid usage and pain scores measured twice, a median of 18 months apart.Data analysis was completed for twenty-six pwHAM, (8♂; 18♀; median age: 57.8 years; median disease duration: 8 years). Median time at baseline to: complete 10m was 17.5 seconds, versus 21.4 seconds at follow up; 23% completed the 6MW compared to 42% at follow up and a median distance of 55m was covered compared to 71m at follow up. Using the 10mTW velocity to predict the 6MW distance, overestimated the distance walked in 6 minutes (p<0.01). Functional decline over time was captured using the functional ambulation categories.The 10mTW velocity underestimated the degree of disability. Gait speed usefully predicts functional domains, shows direction of functional change and comparison with published healthy age matched controls show that these patients have significantly slower gait speeds. The measured differences over 18 months were sufficient to reliably detect change and therefore these assessments can be useful to detect improvement or deterioration within broader disability grades. Walking capacity in pwHAM should be measured using the 10mTW for gait speed and the 6MW for endurance

Comparing the efficacy of metronome beeps and stepping stones to adjust gait: steps to follow!

Acoustic metronomes and visual targets have been used in rehabilitation practice to improve pathological gait. In addition, they may be instrumental in evaluating and training instantaneous gait adjustments. The aim of this study was to compare the efficacy of two cue types in inducing gait adjustments, viz. acoustic temporal cues in the form of metronome beeps and visual spatial cues in the form of projected stepping stones. Twenty healthy elderly (aged 63.2 ± 3.6 years) were recruited to walk on an instrumented treadmill at preferred speed and cadence, paced by either metronome beeps or projected stepping stones. Gait adaptations were induced using two manipulations: by perturbing the sequence of cues and by imposing switches from one cueing type to the other. Responses to these manipulations were quantified in terms of step-length and step-time adjustments, the percentage correction achieved over subsequent steps, and the number of steps required to restore the relation between gait and the beeps or stepping stones. The results showed that perturbations in a sequence of stepping stones were overcome faster than those in a sequence of metronome beeps. In switching trials, switching from metronome beeps to stepping stones was achieved faster than vice versa, indicating that gait was influenced more strongly by the stepping stones than the metronome beeps. Together these results revealed that, in healthy elderly, the stepping stones induced gait adjustments more effectively than did the metronome beeps. Potential implications for the use of metronome beeps and stepping stones in gait rehabilitation practice are discussed

Muscle Activity and Co-Activation of Gait Cycle during Walking in Water and on Land in People with Spastic Cerebral Palsy

Background: The purpose of this study was to investigate the differences in the muscle activity and co-activation index (CoA) of the rectus femoris (RF), biceps femoris (BF), gastrocnemius medialis (GM,) and tibialis anterior (TA) during walking on land and in water in healthy adolescents compared with those with spastic diplegia cerebral palsy (CP) adolescents. Methods: Four healthy individuals (median; age: 14 years, height: 1.57 cm, BMI: 16.58 kg/m2) and nine CP individuals (median; age: 15 years, height: 1.42 cm, BMI: 17.82 kg/m2) participated in this study and performed three walking trials under both conditions. An electromyography (EMG) collection was recorded with a wireless system Cometa miniwave infinity waterproof device, and the signals were collected using customized software named EMG and Motion Tools, Inc. software version 7 (Cometa slr, Milan, Italy) and was synchronized with an underwater VDO camera. Results: A significant decrease in the muscle activity of all muscles and CoA of RF/BF muscles, but an increase in TA/GM was observed within the CP group while walking in water during the stance phase. Between groups, there was a lower CoA of RF/BF and a greater CoA of TA/GM during the stance phase while walking in water and on land in the CP group. A non-significant difference was observed within the healthy group. Conclusion: Walking in water can decrease muscle activity in lower limbs and co-activation of thigh muscles in people with spastic CP, whereas CoA muscles around ankle joints increased to stabilize foot weight acceptance

Gamma-aminobutyric Acid (GABA) Producing Probiotic Lactiplantibacillus Pentosus Isolated from Fermented Spider Plant (Pak Sian Dong) in Thailand

Psychobiotics are defined as the organisms that can provide the mental health benefit. The possible mechanism of psychobiotics is manipulation of neurotransmitter production and neurotransmitter production by the microbes. The lactobacillus group has been reported for the potential of neurotransmitter production, especially g-aminobutyric acid (GABA) which is an important inhibitory neurotransmitter. Therefore, GABA can be used for relaxation and applied in various psychiatric disorders. The aim of this study was determination of lactic acid bacterial isolates from Pak Sian Dong in Thailand for GABA producing ability. The results found that there were 3 isolates, SF66, SF80 and SF82, which revealed the ability to produce glutamic acid decarboxylase (GAD) enzyme. The GABA were detected by thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) in the bacterial culture containing 3% monosodium glutamate. The survival in gastrointestinal synthetic condition found that only SF66 isolate showed the authentic percentage of survival then this isolate was selected. From the identification, the isolate was identified as Lactiplantibacillus pentosus and was designated as L. pentosus SF66 which exhibited with the potential for further investigation and development to be psychobiotics

Validity and reliability of a thoracic kyphotic assessment tool measuring distance of the seventh cervical vertebra from the wall

Background: In primary healthcare (PHC) service, community residents, village health volunteers (VHVs), and healthcare professionals need to work in partnership to facilitate universal and equitable healthcare services. However, these partnerships may need an appropriate tool helping them to execute an effective health-related activity. Objectives: To investigate the reliability and validity of a simple kyphosis measure using a perpendicular distance from the seventh cervical vertebra (C7) to the wall (C7WD). Methods: Elderly people with different degrees of kyphosis (n = 179) were cross-sectionally investigated for the intra- and interrater reliability of the measurement by a physical therapist (PT), VHV, and caregiver. The validity was assessed in terms of concurrent validity as compared with the Flexicurve, and discriminative validity for functional deterioration in participants with mild, moderate, and severe kyphosis. Results: The method showed excellent reliability among PT, VHV, and caregivers (ICC > 0.90, p < 0.001), and excellent correlation to the data from the Flexicurve. Results of the assessment were greater than a level of minimal detectable change and could clearly discriminate functional deterioration in participants with different severity of kyphosis (p < 0.001). Conclusion: C7WD is valid and reliable, thus it can be used to promote the standardisation of kyphosis measures among PHC members