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We have investigated the infrared reflectivity, UV-visible spectra and electrical property of polycrystalline RFeO3 (R = La, Nd, Gd, Dy, Er) synthesized by sol–gel method. Analysis of IR reflectivity spectra through Lorentz oscillator model has led to the observation of 14 IR active phonon modes out of 25 predicted modes. The results have been discussed in terms of different phonon bands related to the origin of atomic vibrations, which provides information about the structural evolution. The energy bandgap ≃ 1.67–1.90 eV estimated from optical conductivity ( σ ( ω )) spectrum is found consistent both with that calculated from UV-visible spectra and estimated from electrical measurements. [ABSTRACT FROM AUTHOR]

This paper presents the design and testing of a control system for the robotic flight of tethered kites. The use of tethered kites as a prime mover in airborne wind energy is undergoing active research in several quarters. There also exist several additional applications for the remote or autonomous control of tethered kites, such as aerial sensor and communications platforms. The system presented is a distributed control system consisting of three primary components: an instrumented tethered kite, a kite control pod, and a ground control and power takeoff station. A detailed description of these constituent parts is provided, with design considerations and constraints outlined. Flight tests of the system have been carried out, and a range of results and system performance data from these are presented and discussed. [ABSTRACT FROM AUTHOR]

We have investigated the optical and electrical properties of polycrystalline DyMn2O5 synthesized by sol-gel method. Analysis of the reflectivity spectrum has led to the observation of 18 infrared (IR) active phonon modes out of 36 predicted ones. We discuss the results in terms of different phonon bands originated as a result of atomic vibrations. Moreover, the optical energy band gap of Eg(OC)~1.78 eV has been estimated from optical conductivity (σ1(ω)) spectrum. The energy band gap and optical transitions were also determined from UV-visible absorption spectrum and band gap of Eg(UV)~1.57 eV was estimated. Moreover, DC electrical resistivity shows the p-type polaronic conduction above room temperature. [ABSTRACT FROM AUTHOR]

Higher grain Zn concentration is desirable to combat human Zn deficiency. A total of 58 farmers' fields were surveyed from districts of Multan and Lodhran to represent cotton-wheat rotation zone of Punjab. Soils were sampled separately from the surface (0–15 cm depth) and subsurface (15–30 cm depth) layers. Within 5 m2 of soil sample, about 100 spikes from mature tillers of wheat were also collected. Nearly all subsurface and 76% of the collected surface soil samples were deficient in plant available Zn resulting in grain Zn concentration of 20 µg g–1, on average. The inherent capacity of subsurface soil layer to supply Zn positively correlated with grain Zn concentration (r=0.33, n=58; P=0.01). Organic matter content (r=0.32, n=58; P=0.02) in subsurface layer and soil salinity (ECe) of both layers (r=–0.53, n=58; P<0.01 for ECe of both layers) were the other major soil characteristics that significantly correlated with grain Zn concentration. Zinc bioavailability in wheat grains, estimated by [phytate]:[Zn] ratios and trivariate model of Zn absorption, was low. Present study indicated a need to reduce current grain [phytate]:[Zn] ratio (46, on average) and to increase the current trivariate model based estimated Zn bioavailability (1.5 mg Zn for 300 g flour, on average) by about 2-folds. Conclusively, Zn fertilization strategy for southern Punjab was suggested as a solution to human Zn deficiency and low grain yields. [ABSTRACT FROM AUTHOR]

The seismic provisions for the Building Code of Pakistan were revised after the 2005 Kashmir earthquake and these have resulted in the introduction of a macrozonation ground motion hazard map in the seismic provisions. The macrozonation map proposes a peak ground acceleration (PGA) for the return period of 475 yr for Pakistan for flat rock sites. After the macrozonation, the next step is to develop the surface ground motion assessment studies for the cities, districts and tehsils of Pakistan. In this study, the probabilistic seismic hazard analysis (PSHA) approach is used for the Peshawar District. The PSHA, consistent with the classical Cornell approach, is carried out to obtain the seismic hazard curves and uniform hazard spectra of PGA values for the return periods of 150, 475, 975 and 2475 yr at a grid spacing of 0.1∘×0.1∘. The PGA for Peshawar at 150, 475, 975 and 2475 yr return period is estimated as 0.23, 0.34, 0.39 and 0.45g, respectively, for rock flat outcrop site conditions. The surface ground motion maps proposed in this study incorporate the local soil effects using amplification factors based on shear wave velocity obtained as a proxy to the topographic slope. The resultant ground surface hazard assessment proposes the PGA value of 0.63g for the return period of 475 yr and 0.89g for the return period of 2475 yr. The maps developed in the current study are important inputs for the structural designing, risk assessment and land use planning of the Peshawar District. [ABSTRACT FROM AUTHOR]

Prediction of mesiodistal width of unerupted buccal segment teeth is crucial for treatment planning in mix dentition. The aim of this study was to validate the applicability of a regression equation proposed by Melgaco for prediction of mesiodistal width of unerupted canine and premolars in mandibular arch (PSCP) in class II division 1 occlusal relations. The study was conducted on one hundred dental casts of class II division 1 patients that were collected after sample size calculation. Actual mesiodistal widths of the mandibular permanent canines and premolars (ASCP) was measured with the help of Vernier calipers. Mesiodistal width of erupted first molar and incisor was also measured. The predicted mesiodistal width of unerupted canine and premolars were determined by Melgaco equation. Descriptive statistics were generated for age, gender, predicted (PSCP) and the actual size of canine and premolars (ASCP). Pearson correlation was used to check the correlation coefficient (r value) and test whether significant correlation exist between the predicted and actual mesiodistal dimensions. A p-value < 0.05 was taken as significant. The study consisted of 37 males and 63 females with mean age of 17.74 ± 2. 14 years. Significant correlation, p-value <0.001 was found between predicted and actual mesiodistal width of canine and premolars in the entire sample along with terms of gender stratification. In conclusion, Melgaco equation shows positive correlation with actual mesiodistal width of the teeth in both genders having class II div I malocclusion with females having higher correlation coefficient. [ABSTRACT FROM AUTHOR]

Objective: To identify the most common allergy type among patients visiting an urban allergy centre., Methods: The descriptive cross-sectional study was conducted at the Allergy Centre of the National Institute of Health, Islamabad, Pakistan, from December 2019 to June 2020, and comprised subjects of either gender aged 20-50 years. Skin prick test was used to determine the skin reactivity for 11 common allergen extracts. Patients with a wheal diameter >3mm were considered positive. Data was analysed using SPSS 22., Results: Of the 100 patients, 55(55%) were males and 45(45%) were females. The overall mean age was 34.03±8.16 years. Majority of the respondents 93(93%) were sensitive to aeroallergen, 7(7%) to food allergens, and 2(2%) exhibited sensitivity against both types of allergens. Poly-sensitisation was found among 86(86%) respondents., Conclusion: Aeroallergens were found to be the main triggering factor for allergies compared to the food allergens.