2,225 research outputs found
The pattern of paediatric respiratory illnesses admitted in Ebonyi state university teaching hospital south east Nigeria
Background: Reports from the developed nations reveal respiratory tract infections as the leading cause of childhood hospital admissions. Children may be admitted for a variety of respiratory illnesses. Data on the spectrum of pediatric respiratory illnesses admitted in the hospital is scarce. Aim: To determine the pattern of pediatrics respiratory illness admissions, seasonal frequency, underlying risk factors and outcome. Subjects and Methods: A retrospective assessment of respiratory cases admitted in the pediatric ward from 2005 to 2010 was conducted using case notes. Parameters considered included month of presentation, age, sex, immunization and nutritional status, tools of diagnosis and patient outcome. Results were analyzed using the Statistical Package for the Social Sciences with the level of significance P ≤ 0.05. Results: Of the 239 cases admitted, there were more males than females (1.4:1). The commonest case was Bronchopneumonia, 71.6% (171/239 out of which 161 were uncomplicated, 5 had effusions and 6 were associated with measles). Other cases were Pulmonary Tuberculosis, 10.9% (26/239), Lobar pneumonia 8.8% (21/239), Bronchiolitis, 5% (12/239), Aspiration pneumonitis 2.1% (5/239) and Bronchial asthma, 0.8% (2/239). Mortality was 7.5% (18/239) mostly from Bronchopneumonia amongst the 1–5 years old. Mortality was significantly associated with malnutrition (P < 0.001) and poor immunization status (P < 0.01). Conclusion: Bronchopneumonia was found to be the commonest illness with significant mortality and peak occurrence in the rainy season. More emphasis must be laid on anticipatory guidance and prevention by encouraging the immunization, good nutrition and increased attention on children even after 1 year of age.Keywords: Admissions, Ebonyi, Nigeria, Pattern, Respiratory illnes
Improvement of performance of InAs quantum dot solar cell by inserting thin AlAs layers
A new measure to enhance the performance of InAs quantum dot solar cell is proposed and measured. One monolayer AlAs is deposited on top of InAs quantum dots (QDs) in multistack solar cells. The devices were fabricated by molecular beam epitaxy. In situ annealing was intended to tune the QD density. A set of four samples were compared: InAs QDs without in situ annealing with and without AlAs cap layer and InAs QDs in situ annealed with and without AlAs cap layer. Atomic force microscopy measurements show that when in situ annealing of QDs without AlAs capping layers is investigated, holes and dashes are present on the device surface, while capping with one monolayer AlAs improves the device surface. On unannealed samples, capping the QDs with one monolayer of AlAs improves the spectral response, the open-circuit voltage and the fill factor. On annealed samples, capping has little effect on the spectral response but reduces the short-circuit current, while increasing the open-circuit voltage, the fill factor and power conversion efficiency
Grout rheological properties for preplaced aggregate concrete production
yesThis paper investigates the effect of cement based grout rheology on the injection process through coarse aggregate for producing preplaced aggregate concrete. Four different sands were used in the grout production at different water-cement ratios and cement-sand ratios. Superplasticiers and pulverised fuel ash were also employed in the grout production. Coarse aggregate of known weight was compacted into 150 mm cubic forms, and then the grout was injected through a plastic pipe under self weight into the stone ‘skeleton’. It has been found that there are threshold values of the rheological parameters beyond which full injection is not possible. In particular, all grout mixes with and without additives and admixtures exhibited the same yield stress threshold value for full injection, whereas the threshold values for other rheological properties including the grout plastic viscosity, flow time and speed were different according to the materials added to the mix
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The influence of community factors on the engagement of residents in place promotion: Empirical evidence from an Italian heritage site
The engagement of community residents in place promotion is increasingly recognized as desirable for ensuring effective and reliable communication with tourists. The study investigated the effects of community factors on residents' engagement in the promotion of an Italian heritage site. Community commitment, environmental attitudes, and perceptions of the effectiveness of existing place marketing communications were found to be decisive in influencing residents' engagement in the promotion of the Amalfi Coast. The paper helps to shed light on collaboration in place promotion, thus enriching the debate on the ambassadorship role of residents and suggesting useful insights for policy makers/destination management organization
Cycling comfort on asphalt pavement: Influence of the pavement-tyre interface on vibration
Attainment of cycling comfort on urban roads encourages travelers to use bicycles more often, which has social and environment benefits such as to reduce congestion, air pollution and carbon emissions. Cycling vibration is responsible for the cyclists’ perception of (dis)comfort. How asphalt pavement's surface characteristics relate to cycling comfort, however, remains undiscovered. In this study, the cycling vibration intensity on 46 sections of 24 urban roads was tested using a dynamic cycling comfort measure system while the cyclists’ perception of vibration was identified via questionnaires; the cycling comfort was then defined based on the cycling vibration. To record the accurate pavement-tyre interface under a stable environment, a total of 19 pavement sections were scanned using a 3D digital camera. These 3D models were then 3D printed, which are used to conduct the pressure film test using a self-developed pavement-tyre interface test system. Three ranges of pressure films were adopted to characterize the pavement-tyre interface via 9 parameters, namely contact area (A c ), unit bearing area (B u ), stress intensity (S i ), stress uniformity (S u ), kurtosis (S ku ), spacing (Sp a ), maximum peak spacing (Sp max ), radius ratio (R r ) and fractal dimension (F d ), in consideration of the area characteristics, pressure amplitude, peak spacing and shape of the interface. Finally, the significant interface parameters were identified, and the regression model between interface parameters and cycling comfort was established. Results show that the cycling vibration was described to be ‘very comfortable’ when the human exposure to vibration level (a wv ) was less than 1.78 m/s 2 ; ‘comfortable’ when the a wv was between 1.78 m/s 2 and 2.20 m/s 2 ; and ‘uncomfortable’ when the a wv was greater than 2.20 m/s 2 . The average stress on rear wheel-pavement interface is higher than that of the front wheel. B u-0.6 , Sp a-0.6 , and F d-0.6 are significant to cycling vibration. The 2LW pressure film is recommended for use to measure the bicycle pavement-tyre interface. The recommended interface characteristics are less than 7 mm 2 of the unit bearing area, 6 mm of average spacing and 2.38 of fractal dimension. Finally, dense asphalt mixture performs better in providing cycling comfort than the gap-graded asphalt mixture. Results of this study contribute to current knowledge on bike lane comfort and pavement design, the findings should be interested in cyclists, transport planners, and road authorities
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Mechanical properties of martensitic alloy AISI 422
HT9 is a martensitic stainless steel that has been considered for structural applications in liquid metal reactors (LMRs) as well as in fusion reactors. AISI 422 is a commercially available martensitic stainless steel that closely resembles HT9, and was studied briefly under the auspices of the US LMR program. Previously unpublished tensile, fracture toughness and charpy impact data on AISI 422 were reexamined for potential insights into the consequences of the compositional differences between the two alloys, particularly with respect to current questions concerning the origin of the radiation-induced embrittlement observed in HT9. 8 refs, 8 figs
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