151 research outputs found
In situ XRD studies of the effect of catalyst pre-treatment strategies on the bulk structure and performance of Mo-V-Te-Nb catalysts for selective oxidation of propane.
Current research efforts are concentrated towards utilizing propane rather than propylene as the feedstock in the industrial process for producing acrylic acid because of its significant lower price. The discovery of the MoVTe family of catalysts has brought this goal within sight. This study investigates the effect of different calcination protocols using in situ XRD. A series of catalyst precursors were treated at different calcination temperatures and atmospheres, while analysing their structures with XRD. The conditions necessary for crystallization of known active phases were determined. The activity of the same catalysts was also tested using a nanoflow high throughput reactor. A structure – activity study leads to correlations between synthesis, phase equilibria and performance of these Mo-V-Te-Nb catalysts for selective oxidation of propane
Analysis of structural transformations during the synthesis of a MoVTeNb mixed oxide calalyst
This work presents a detailed investigation of the preparation routine for the multi-metal oxide Mo1V0.30Te0.23Nb0.125Ox used as catalyst for the selective oxidation of propane to acrylic acid. In situ Raman spectroscopy on the initial aqueous polyoxometalate solution prepared from ammonium heptamolybdate, ammonium metavanadate and hexaoxotelluric acid reveals the coexistence of Anderson-type anions [TeM6O24]n−, M = Mo, V; n ≥ 6 and protonated decavanadate species [HxV10O28](6−x)−. Raman analysis showed that the monomeric motif of the Anderson-type tellurate is preserved after addition of the Nb precursor and the subsequent spray-drying process. Calcination of the X-ray amorphous spray-dried material in air at 548 K seems to be the essential step, leading to a re-arrangement of the tellurate building blocks, generating nanocrystalline precursors of the phases finally established during treatment in helium at 873 K
Field evaluation of a simple fluorescence method for detection of viable Mycobacterium tuberculosis in sputum specimens during treatment follow-up.
Simple tuberculosis (TB) treatment monitoring tools are needed. We assessed the performance of fluorescein-diacetate (FDA) smear microscopy for detection of viable Mycobacterium tuberculosis in sputum specimens (n = 288) of TB cases under treatment compared to culture (17.4% culture positivity). FDA sensitivity was moderate (83.7% [95% confidence interval {CI}, 70.3 to 92.6]), and specificity was low (66.1% [59.5 to 72.2]). The good negative predictive value (94.8% [90.1 to 97.8]) and negative likelihood ratio (0.2) suggest using this method to rule out treatment failure in settings without access to culture
The Influence Of Geometrical Dimensions On Electromechanical Performance In Stretchable Circuit
Stretchable conductive ink (SCI) had been extensively studied for fabricating stretchable electronic devices. In this study, silver conductive ink and thermoplastic polyurethane (TPU) were used as substrate. The ink was printed on the substrate using screen printing with different shaped patterns varied by the widths of 1 mm, 2 mm and 3 mm: (a) straight, (b) zig-zag, (c) square and (d) sinusoidal. The measurement of resistance was performed using four-point measurement during unloaded and loaded conditions of the shape pattern. This study revealed that width had influenced the resistivity in all shape patterns, where the narrow the width, the higher the resistance is. Comparative studies of electromechanical analysis of the shaped patterns had showed that a 3 mm width of zig-zag pattern had a better electromechanical performance by having stretchability to maximum of 7.78%. Straight and square shape patterns, however, exhibited the poor tolerate deformation as both failed to conduct electricity upon straining at the minimum elongation of 1.11%
Electrocardiographic ECG characteristics among Malaysian athletes
The electrocardiogram (ECG) is a graphic representation of the heart’s electrical activity. Although it has some limitations as a diagnostic or prognostic tool, it contains a wealth of information necessary for the proper care of a patient with a potential cardiovascular disease. Understanding the ECG changes among athletes would allow medical practitioners to distinguish between normal physiological adaptations and abnormal changes. However, there is limited data on the ECG characteristics among multi-ethnic athletes such as in Malaysia. This study aimed to determine the ECG
characteristics and its associated factors among Malaysian national athletes. Malaysian national athletes annual preparticipation medical records were retrieved. Information on sociodemographic, sports and medical history including the 12-lead resting ECG tracings were extracted. ECG were assessed and categorised into normal, physiological adaptation changes, and abnormal ECG using the standardised ‘Seattle criteria’. Differences in ECG characteristics
between genders, ethnic background, and type of sports was investigated. Additionally, factors associated with the ECG characteristics were assessed using multiple logistic regression. Majority of Malaysian national athletes had physiological adaptation ECG changes (61%). The most frequent changes were early repolarization, sinus bradycardia and isolated left ventricular hypertrophy. We found significantly higher prevalence of physiological adaptation changes among men (χ2 (2,371) = 18.9; p = 0.001) and athletes of Chinese ethnicity (both genders) (χ2
(2,356) = 13.8; p = 0.002). Factors associated with physiological ECG changes were men (OR=2.67; 95% CI= 1.68, 4.27; p<0.001) and Chinese
ethnicity (OR=2.92; 95% CI=1.68, 4.27; p=0.039). Most athletes had physiological adaptation ECG changes which were significantly associated with male gender and Chinese ethnicity. This information would facilitate the development of a specific guideline in interpreting ECG among Malaysian athletes
EXAMINING AND CORRELATION ANALYZE OF THE RELATIONSHIP BETWEEN FUNCTIONAL MOVEMENT SCREENING TEST (FMS) AND UPPER LIMB FUNCTION IN ELITE BASKETBALL PLAYERS AL- RAFIDAIN SPORTS CLUB
Background Functional Movement Screening (FMS) becomes more and more popular in identifying functional limitations in basic functional movements. This experimental study was conducted to confirm the feasibility of implementing FMS among active Elite Basketball Players Al-R afidain Sports Club. The purpose of this study is to investigate the relationship between the functional sports screen (FMS) of Elite Basketball Players Al- Rafidain Sports Club and upper limb`s function Methods It is essential to have more practical and comprehensive alternatives of exercise screening for understanding human function and identifying impairments and dysfunctional exercise patterns that reduce functional quality. In many cases, weakness or tension in muscles or muscle groups is usually found, then treated with separate stretching or strengthening activities, rather than using standard exercise patterns that can solve multiple injuries at the same time. Likewise, many professionals usually focus on specific areas of complaint, rather than starting with identifying comprehensive motor characteristics and correlating that characteristic with dysfunction. The study group consisted of 60 Elite Basketball Players from Al- Rafidain Sports Club; with age between 17 and 36. Their height was 175–220 cm, weight – 65–85 kg, BMI was calculated and recorded digitally for later analysis. The inclusion criterion was absence of a history of musculoskeletal injury at least 3 months before investigation. FMS consists of 7 component tests to evaluate different basic movement modes (squat, hurdle step, overhead squat, inline lunge, shoulder flexibility, straight leg elevation test, trunk stability push-up test). Arm Disability Assessment Questionnaire (DASH) has been used to assess upper limb function as an evaluation tool for the prevention of sports injuries. Pearson correlation coefficient with significance p ≤ 0.05 was used to test the relationship between variables Resulte: The results show that there is a difference between the performance screening test scores for measuring arm disability and the high scores. (P = 0.01, R = –.068) There is a strong relationship. Conclusion It seems necessary for coaches and sports experts to choose suitable tests for athletes to prevent sports injuries. This could effectively reduce the cost of treatment and improve the level of exercise. Therefore, based on the results of this study, it can be said that the test which has been introduced could be used as an assessment tool for injury prevention. However, its relationship with other functional tests and some factors of physical fitness has not been studied
Electrocardiographic (ECG) characteristics among Malaysian athletes
The electrocardiogram (ECG) is a graphic representation of the heart’s electrical activity. Although it has some limitations as a diagnostic or prognostic tool, it contains a wealth of information necessary for the proper care of a patient with a potential cardiovascular disease. Understanding the ECG changes among athletes would allow medical practitioners to distinguish between normal physiological adaptations and abnormal changes. However, there is limited data on the ECG characteristics among multi-ethnic athletes such as in Malaysia. This study aimed to determine the ECG characteristics and its associated factors among Malaysian national athletes. Malaysian national athletes annual pre-participation medical records were retrieved. Information on sociodemographic, sports and medical history including the 12-lead resting ECG tracings were extracted. ECG were assessed and categorised into normal, physiological adaptation changes, and abnormal ECG using the standardised ‘Seattle criteria’. Differences in ECG characteristics between genders, ethnic background, and type of sports was investigated. Additionally, factors associated with the ECG characteristics were assessed using multiple logistic regression. Majority of Malaysian national athletes had physiological adaptation ECG changes (61%). The most frequent changes were early repolarization, sinus bradycardia and isolated left ventricular hypertrophy. We found significantly higher prevalence of physiological adaptation changes among men (χ2(2,371) = 18.9; p = 0.001) and athletes of Chinese ethnicity (both genders) (χ2(2,356) = 13.8; p = 0.002). Factors associated with physiological ECG changes were men (OR=2.67; 95% CI= 1.68, 4.27; p<0.001) and Chinese ethnicity (OR=2.92; 95% CI=1.68, 4.27; p=0.039). Most athletes had physiological adaptation ECG changes which were significantly associated with male gender and Chinese ethnicity. This information would facilitate the development of a specific guideline in interpreting ECG among Malaysian athletes
Health Extension Workers Improve Tuberculosis Case Detection and Treatment Success in Southern Ethiopia: A Community Randomized Trial
Background: One of the main strategies to control tuberculosis (TB) is to find and treat people with active disease. Unfortunately, the case detection rates remain low in many countries. Thus, we need interventions to find and treat sufficient number of patients to control TB. We investigated whether involving health extension workers (HEWs: trained community health workers) in TB control improved smear-positive case detection and treatment success rates in southern Ethiopia. Methodology/Principal Finding: We carried out a community-randomized trial in southern Ethiopia from September 2006 to April 2008. Fifty-one kebeles (with a total population of 296, 811) were randomly allocated to intervention and control groups. We trained HEWs in the intervention kebeles on how to identify suspects, collect sputum, and provide directly observed treatment. The HEWs in the intervention kebeles advised people with productive cough of 2 weeks or more duration to attend the health posts. Two hundred and thirty smear-positive patients were identified from the intervention and 88 patients from the control kebeles. The mean case detection rate was higher in the intervention than in the control kebeles (122.2% vs 69.4%, p,0.001). In addition, more females patients were identified in the intervention kebeles (149.0 vs 91.6, p,0.001). The mean treatment success rate was higher in the intervention than in the control kebeles (89.3% vs 83.1%, p = 0.012) and more for females patients (89.8% vs 81.3%, p = 0.05). Conclusions/Significance: The involvement of HEWs in sputum collection and treatment improved smear-positive case detection and treatment success rate, possibly because of an improved service access. This could be applied in settings with low health service coverage and a shortage of health workers
Are 'Village Doctors' in Bangladesh a curse or a blessing?
<p>Abstract</p> <p>Background</p> <p>Bangladesh is one of the health workforce crisis countries in the world. In the face of an acute shortage of trained professionals, ensuring healthcare for a population of 150 million remains a major challenge for the nation. To understand the issues related to shortage of health workforce and healthcare provision, this paper investigates the role of various healthcare providers in provision of health services in Chakaria, a remote rural area in Bangladesh.</p> <p>Methods</p> <p>Data were collected through a survey carried out during February 2007 among 1,000 randomly selected households from 8 unions of Chakaria <it>Upazila</it>. Information on health-seeking behaviour was collected from 1 randomly chosen member of a household from those who fell sick during 14 days preceding the survey.</p> <p>Results</p> <p>Around 44% of the villagers suffered from an illness during 14 days preceding the survey and of them 47% sought treatment for their ailment. 65% patients consulted Village Doctors and for 67% patients Village Doctors were the first line of care. Consultation with MBBS doctors was low at 14%. Given the morbidity level observed during the survey it was calculated that 250 physicians would be needed in Chakaria if the patients were to be attended by a qualified physician.</p> <p>Conclusions</p> <p>With the current shortage of physicians and level of production in the country it was asserted that it is very unlikely for Bangladesh to have adequate number of physicians in the near future. Thus, making use of existing healthcare providers, such as Village Doctors, could be considered a realistic option in dealing with the prevailing crisis.</p
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