Optimal-Dimensionality Sampling on the Sphere: Improvements and Variations

For the accurate representation and reconstruction of band-limited signals on the sphere, an optimal-dimensionality sampling scheme has been recently proposed which requires the optimal number of samples equal to the number of degrees of freedom of the signal in the spectral (harmonic) domain. The computation of the spherical harmonic transform (SHT) associated with the optimal-dimensionality sampling requires the inversion of a series of linear systems in an iterative manner. The stability of the inversion depends on the placement of iso-latitude rings of samples along co-latitude. In this work, we have developed a method to place these iso-latitude rings of samples with the objective of improving the well-conditioning of the linear systems involved in the computation of the SHT. We also propose a multi-pass SHT algorithm to iteratively improve the accuracy of the SHT of band-limited signals. Furthermore, we review the changes in the computational complexity and improvement in accuracy of the SHT with the embedding of the proposed methods. Through numerical experiments, we illustrate that the proposed variations and improvements in the SHT algorithm corresponding to the optimal-dimensionality sampling scheme significantly enhance the accuracy of the SHT.Comment: 5 Pages, 4 figure

Low prevalence of asthma among textile workers in Karachi, Pakistan

Objective: To determine the prevalence of asthma in textile workers through post-bronchodilator spirometry and to compare the differences in prevalence based on different criteria used to assess asthma.Methods: The cross-sectional study was conducted between July and December 2013 in Karachi, Pakistan, and comprised workers from15 textile mills in the city and its outskirts. Asthma and associated respiratory symptoms were assessed using the American Thoracic Society Division of Lung Diseases Questionnaire, and post-bronchodilator spirometry. SPSS 19 was used for statistical analysis.Results: Among the 372 workers in the study, asthma was found in 19(5%) as diagnosed on post-bronchodilator spirometry. The prevalence of self-reported and physician-diagnosed asthma was 15(4%) and 8(2%) respectively. Work in the spinning section, age ≥38 years, duration of work ≥10 years in textile industry, history of smoking, and ≥10 pack years of smoking were found to be important predictors of asthma.Conclusions: Textile industry workers had low prevalence of asthma, assessed through post-bronchodilator spirometry, compared to estimates for the general population. This could possibly be due to some protective effect of endotoxin exposure although further evaluation with better exposure assessment is warranted

Fabrication and characterization of CNT/ZnO thin film junction for photovoltaic application

Concern about energy supply and climate change has been brought into the essential discussion. There is a clear need to make energy cheap, readily accessible and green. The Photovoltaic cell (PV) is the energy source in the development of solar cell technology that can deliver low cost electricity generation. Therefore, this research work is conducted on the fabrication and characterization of CNT/ZnO thin films junction for photovoltaic application. The preparation procedure includes two parts: deposition of ZnO by the electrodeposition technique and coating of CNTs by the doctor-blade technique. Effect of different deposition temperatures at 60°C, 75°C and 90°C on the structural and morphological ZnO films was studied and the optimum deposition conditions have been outlined. XRD shows that the product presents a good crystallinity. The characterization of structural and morphological of CNT films were studied by using XRD and FESEM. The XRD results showed the crystalline size of CNTs in nano size. CNTs have been used as the component devices to help the charge conduction, improve electrode flexibility and in some cases as active light absorbing materials. The ultimate goal is to gain deeper understanding of the cathodic processes involved and to facilitate the optimization of operating conditions

Optimization of TiO2 thin film thickness for dye sensitized solar cell applications

Dye sensitized solar cells (DSSCs) rely on the absorption of photons by the dye molecules which are transported to the conduction band of the TiO2 electrode. The microstructure, energy gap and the absorption spectra of the TiO2 electrodes highly affects the efficiency of the cell. In this paper, the absorption spectra and energy gap has been studied by varying the thickness of the TiO2 paste. Nanocrystalline TiO2 thin films were deposited on ITO glass substrate with three different thickness (4.54μm, 7.12μm and 12.3μm) by using doctor blade method. After deposition all the samples were sintered at 450°C after deposition to enhance the particle bonding and for achieving better adhesion. The samples were characterized by UV-VIS spectra for determining the absorption spectra and Scanning Electron Microscopy (SEM) for investigating the thickness and the surface morphology. Fabricating the electrodes with different thickness showed significant changes in the energy gap and from the results it can be concluded that the energy gap increases with the increased thickness. The highest energy gap of 2.25ev and absorption 3.791 was achieved by 12.3μm thick sample. The absorption spectra also shows better absorption throughout the whole visible light range but the SEM images suggests that 12.3μm thick sample shows cracks all over the deposited region which will cause current leakage when the cell is assembled. Therefore, the optimum result was achieved by 7.12μm thick sample providing 1.9 ev energy gap and 3.91 absorption peak

Effects of city wastewater on the characteristics of wheat with varying doses of nitrogen, phosphorus, and potassium

Rapidly growing India is not only facing the problem of water scarcity, but also the mismanagement of tremendous amount of wastewater produced every day. Moreover, food sufficiency has also become challenge to feed the ever increasing population leading to excessive use of chemical fertilizers in agriculture. Therefore, the study was carried out in Aligarh City of India on wheat crop (Triticum aestivum L.) var. PBW 343 to check the suitability of city wastewater as a source of irrigation water as well as source of nutrients. Three pot experiments were conducted in the winter season of 2006-2008. In Experiment I, nitrogen (N) at the rate of 0, 40, 80, 120 kg ha-1; Experiment II, phosphorus (P) at the rate of 0, 20, 40, 60 kg ha-1; and in Experiment III, potassium (K) at the rate of 0, 15, 30 and 45 kg ha-1 were applied along with the basal doses under the three levels of water; ground water (GW), 50% wastewater (WW) and 100% WW. Lower fertilizer doses, 80 kg N ha-1, 40 kg P ha-1 and 30 kg K ha-1 together with 100%WW proved optimum in three experiments, respectively, enhancing tiller number plant-1, fresh mass plant-1, dry matter plant-1, leaf area, total chlorophyll content, photosynthetic rate (PN), nitrate reductase (NR) activity, yield parameters (ear number plant-1, length ear-1, spikelet number ear-1, grain number ear-1 and 1000 grain weight), ultimately resulting in improved grain yield as well as grain carbohydrate and protein content as compared to control as well as higher fertilizer doses. Thus wastewater application not only provided stable supply of water, but also saved fresh water and contributed to environmental security. Moreover, it reduced the use of chemical fertilizers without showing any adverse effect on the yield and quality of wheat. Physicochemical characteristics of wastewater along with microbiological and some heavy metals were analyzed, and most of them were within the permissible limits set by Food and Agriculture Organization (FAO)

Synthesis of heterogeneous catalyst for the production of biodiesel from soybean oil

This study explore the comparison of a suitable heterogeneous catalyst for conversion of triglyceride into fatty acid methyl ester. A series of heterogeneous cerium, manganese, and zinc oxide catalyst supported at mixture of cinder was prepared by co-precipitation and applied for conversion of triglyceride in oil to biodiesel using methanol as solvent. Results showed that a maximum TG conversion of 99% was obtained in the transesterification reaction catalyzed by CeSO4+MnSO4+K2CO3  catalyst calcinated in 5 h at 600oC under the optimal conditions as catalyst amount of 3%, Ce:Mn:K molar ratio of 1:1:1. The catalytic activity of catalyst at 70 ºC reaction temperature was over 90% after 6h. The experimental data were satisfactorily predicted at 99% confidence level. However, due to high and efficient yield CeSO4+MnSO4+K2CO3 catalyst was identified as the most potential catalyst.Keywords: biodiesel fuel; heterogeneous; trans-esterification; rare earth metals; eco-friendly regent; used oi

The key roles of salicylic acid and sulfur in plant salinity stress tolerance

The salinization of agriculture soils over the globe has become one of the most devastating stresses and is significantly limiting cultivated land area, and crop productivity and quality. It is very imperative to explore both salinity tolerance in plants and insights into approaches (and underlying mechanisms) for effectively controlling salinity impacts. To this end, the role of phytohormone salicylic acid (SA) and plant nutrient sulfur (S) in promoting salinity tolerance has been researched in isolated studies, and SA–S interaction results have been little discussed. Given this, taking into account recent literature on SA, S and soil salinity, this paper aimed to (i) overview of the major impacts of soil salinity on plant health; (ii) highlight the significance of SA and S in improving plant salinity tolerance; (iii) discuss the role and underlying mechanism of SA, S and their interaction in the modulation of plant growth and development under salinity stress; and also to (iv) appraise the discussed literature and enlighten the major prospects

Deriving a Preference-Based Measure for Myelofibrosis from the EORTC QLQ-C30 and the MF-SAF

AbstractBackgroundUtility values are required for economic evaluation using cost-utility analyses. Often, generic measures such as the EuroQol five-dimensional questionnaire are used, but this may not appropriately reflect the health-related quality of life of patients with cancer including myelofibrosis.ObjectiveTo derive a condition-specific preference-based measure for myelofibrosis using appropriate existing measures, the Myelofibrosis-Symptom Assessment Form and the European Organisation for Research and Treatment of Cancer Quality of Life 30 Questionnaire.MethodsData from the Controlled Myelofibrosis Study with Oral JAK Inhibitor Treatment trial (n = 309) were used to derive the health state classification system. Psychometric and factor analyses were used to determine the dimensions of the classification system. Psychometric and Rasch analyses were then used to select an item to represent each dimension. Item selection was validated with experts. A selection of health states was valued by members of the general population using time trade-off. Finally, health state values were modeled using regression analysis to produce utility values for every state.ResultsThe Myelofibrosis 8 dimensions has eight dimensions: physical functioning, emotional functioning, fatigue, itchiness, pain under ribs on the left side, abdominal discomfort, bone or muscle pain, and night sweats. Regression models were estimated using time trade-off data from 246 members of the general population valuing a total of 33 states. The best performing model was a random effects maximum likelihood model producing utility values ranging from 0.089 to 1.ConclusionsThe Myelofibrosis 8 dimensions is a condition-specific preference-based measure for myelofibrosis. This measure can be used to generate utility values for myelofibrosis for any data set containing the Myelofibrosis-Symptom Assessment Form and the European Organisation for Research and Treatment of Cancer Quality of Life 30 Questionnaire data