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Investigating the Influence of Cosmic Rays on Ozone Layer Depletion at Beijing, China
Get PDFIn the present study monthly and annually data of ozone depth and cosmic rays (CRs) intensity at China Beijing during the period of 1984-2010 have been analyzed to investigate the effects of cosmic rays intensity on ozone layer depletion (OLD). This communication implements statistical analysis on the data sets for the specified period mentioned above. The analyses exhibit that mean monthly variation of cosmic rays intensity increases. Our investigation claims that in the month of May (1984-2010) changes occurred in the decrease the ozone depth due to the increase in cosmic rays intensity .This sort of study confirms cosmic rays influence on the ozone layer depletion
Troubleshooting Techniques of Complex Multi-Layered PCBs
Get PDFIn this modern era where technology is rapidly changing and is being advanced day by day, Pakistan is dependent on foreign OEM (Original Equipment Manufacturer) for the functional supportability of the systems because most of the commercial and non-commercial systems are foreign OEM based. In the case of any defect of the systems and to reduce the dependency on OEM, the simplest way is to troubleshoot the PCBs (Printed Circuit boards) of the system locally instead of purchasing new PCB or sending it back to OEM for repair until we are able to design our own systems. Thus, it won’t be wrong saying “time, tide and technology wait for none”. The purpose of this research is to achieve self-reliance in PCB troubleshooting, thereby reducing dependability on foreign OEMs, equipment downtime and high costs being acquired in PCB repairs, secondly to highlight the importance of this field so that universities may adopt it as a subject. This research paper is based on some troubleshooting techniques for repair of complex multilayered PCBs
Gamma Dosimetric Response of Sandalfix Golden Yellow CRL Dye Solutions for Gamma Dosimetry Using Cs137 in the Range 0-1KGy
Get PDFThe effect of gamma radiation source (Cs137) on the aqueous solutions of the Sandalfix Golden Yellow CRLdye was determined in the range 0-1kGy. ?max of the dye was determined by UV/VIS spectrophotometer before the exposure of gamma radiations and was found to be 422 nm. Absorbance of the sample solutions was studied at ?max of the dye at pre and post irradiation. It was determined that the Absorbance of the sample solutions was decreased with increasing absorbed dose. The exposed dye solutions were found to be discolored due to the structural changes in the dye solutions and the discoloration of the dye was found linear with respect to absorbed dose
Dosimetric Evaluation and Verification of External Beam 3-D Treatment Plans in Humanoid Phantom Using Thermoluminescent Dosimeters (TLDs)
Get PDFDosimetric Evaluation & Verification Of External Beam 3-D Treatment Plans In Humanoid Phantom have been carried out. In this study male anthromorphic phantom, model no.702 D, manufactured by Atom Ltd has been used. The plan was delivered to phantom and TLD- 100 was placed in cavities to evaluate and verify the dose delivered by implementing 3D treatment plans. TLD 100 was calibrated using SIEMENS PRIMUS PLUS Linear Accelerator with calibrated 6 MV X ray beam. We chose phantom skull, abdomen and pelvis region for making treatment plans and then doses by treatment plans have been verified by TLDs. 4%, 3.5% and 3% variation in the results was found for skull, pelvis and abdomen region respectively which is within the safe limit of accuracy i-e from 3% to 5 %. Before working with TLDs, it has also been found that thermoluminescent dosimeters were showing the linear response and results are reproducible for the dose range from 50 cGy to 200 cGy. This study has been performed at Karachi Institute of Radiotherapy and Nuclear Medicine (KIRAN) during the year 2010-2011
Invasion, Impact and Control Techniques for Invasive Ipomoea hildebrandtii on Maasai Steppe Rangelands
No full textThe ecosystem integrity of the Simanjiro Maasai steppe rangeland in Tanzania is threatened by the invasive plant Ipomoea hildebrandtii Vatke. However, its invasion status, impact and control techniques are unclear in the country. We conducted a study in Terrat and Sukuro villages in Simanjro District, Tanzania, to assess its invasion status and impact across grassland–woodland habitats using point sampling techniques. Key informant interviews and questionnaires were used to assess techniques used by the Maasai pastoralists to control I. hildebrandtii. A total of 10 plots (70 m2 each) with 9 quadrats (1 m2 each) in the invaded and non–invaded sites were established to study I. hildebrandtii invasions. The impact of I. hildebrandtii on rangelands was investigated by comparing herbage (herbaceous vegetation) species composition, richness, basal cover and biomass productivity between invaded and non–invaded plots. Results revealed that I. hildebrandtii invasion was higher in grass woodland habitats (90%) than in non-invaded plots. Non–invaded plots exhibited higher biomass productivity (0.289 ± 0.03 t DM/ha) than invaded plots (0.202 ± 0.02 t DM/ha). Furthermore, non–invaded plots had a higher basal cover (grasses: 54.71 ± 1.95%, forbs: 45.29 ± 1.95%) compared with invaded plots. We also recorded high native plants abundance in quadrats with low I. Hildebrandtii density (22.00 ± 1.36). Additionally, 81% of Maasai pastoralists reported to manually (uproot) control I. hildebrandtii. Based on the results of our study, we recommend further research and novel control techniques coupled with education to be implemented in the Simanjiro
Genetic Retrospect of Seedcotton Yield and its Components from a 6-Parent Gossypium hirsutum Diallel Cross Under Water Stress Conditions
Get PDFA six-by-six complete F1 Gossypium hirsutum, L. diallel cross of three pre-screened drought tolerant and three drought susceptible varieties (CRIS-134, CRIS-342, SINDH-1, NIAB-78, SADORI and BH-160) was evaluated for genetic parameters during 2009 at Sindh Agriculture University farm, Tandojam. The characters studied were number of bolls per plant, sympodial branches per plant, seedcotton yield per plant and lintcotton yield per plant. The objective of such study was to assess the effect of irrigation stress on the genetic inheritance pattern of above quantitative traits as to how far the genetic parameters are affected due to irrigation stress in the F1 diallel generation. Irrigation treatments were four; normal seven irrigations schedule, five irrigations, four irrigations (medium stress) and three irrigations up to 150 days of crop maturity (stress conditions). CRIS-134 in seven, Sadori in five and CRIS-342 in four and three irrigations treatments were the most recessive parents contributing increasing boll number into their progenies while BH-160 in seven, CRIS-342 in five and Sindh-1 in four and three irrigations treatments proved to be the most dominant parents responsible for contributing decreased boll number per plant into their progenies. Seedcotton per plant was partial dominant in seven irrigations treatment while it inherited as an overdominant trait in five, four and three irrigations respectively. BH-160 was the most recessive of all with increased sympodia contributing attributes in seven and four irrigations whereas Niab-78 in five and CRIS-342 in stress were the most recessive parents. Sindh-1 was the most dominant parent in seven, five and three irrigation treatments while CRIS-342 in four irrigations yielded decreased sympodia contributing attributes into their progenies. Sindh-1 in seven, BH-160 in five and three and CRIS-342 in four irrigations treatments proved to be the most recessive parents with increasing seedcotton yield attributes while CRIS-342 in seven and five and Sindh-1 in four and three irrigations were the most dominant parents contributing decreased seedcotton yield into their progenies. Inheritance trend of lintcotton per plant was similar to that of seedcotton yield per plant
Socio-Agricultural Correlation and Regionalization: A Case of the Districts of Pakistan
Get PDFThe main economic activity of a large segment of population in Pakistan is agriculture. The contrasting pattern of topography and uneven distribution of resources create a wide difference in socio-agricultural relationship among the different administrative districts of the country. The study aims to investigate the correlation based on a number of variables extracted from different sectors of Pakistan’s agriculture and social infrastructure. In order to study the regionalization multivariate analysis has been done for hundred districts of Pakistan. The results produced, show sharp variation of regional disparity among the different districts of Pakistan. A clear cut longitudinal east-west divide is visible from the outcome of the study. The provinces of Punjab and Sindh, consisting of fertile plains of river Indus and its tributaries stand out with better socio-agricultural correlation. The western provinces of Khyber Pakhtoonkhwa and Balochistan, surrounded by mountains and plateau depict a deprived scene in terms of socio-agricultural well-being. In Pakistan districts are very vital for resource planning and development. These administrative units have a mix of both rural and urban activities that is why this study becomes more significant for future district planning decisions
Determination of Angstrom Coefficients for Masvingo and Makoholi Stations, Zimbabwe
Get PDFCoefficients of the first order and second order Angstrom model were obtained for Masvingo and Makoholi stations in Zimbabwe. Long term average ground measurements of sunshine hours and global horizontal solar radiation from the meteorological services were used as input data. Monthly average values of the clearness index, and the fraction of sunshine hours, were determined. Regression analysis was used to obtain the first and second order coefficients of the Angstrom model for the two locations. The estimates from the developed models were tested against measured values and results obtained were in agreement to within +/- 5%. The results also showed that the models performed better with these coefficients compared with coefficients suggested in previous researches. Also the first order model was found to perform better than the second order model for Makoholi station while the second order model works well for Masvingo
Digestive Discomforts and Effect of Ingested Food in People Performing Hajj
Get PDFA variety of health issues have been investigated in the Hajj pilgrims (HPs) in KSA. However, it is still obscure to decide which meals contribute to health related issues specifically gastrointestinal disorders and allergies. Hence present study was planned to compare the effect of using different meals on GIT disorders and allergies.
The data was categorized into two groups. Group 1 of age matched HPs comprised a Functional Digestive System Questionnaire (FDSQ) to study digestive disorders. Group 2 HPs were compared for those received Toafa Corporation Meals (TCM) and those did not received Toafa Corporation Meals (NTCM).
The FDSQ showed some of the gastrointestinal symptoms in male and female Hajj pilgrims differing significantly (p<0.05). The efficacy of the treatment was evaluated by subject recovery scoring (SRS). The 61.7% HPs taking TCM revealed various discomforts and food allergy and the 50.6% HPs using NTCM did not suffer from any disorders. However, the pilgrims taking the meals provided by the Toafa corporation but not showing allergy were more significant in number (p=0.0002).
The existing study presents a new method (construction of a FDSQ) for comparing gastrointestinal and other disorders. The present study recommends that Toafa Corporation should provide suitable meals for thepilgrims to meet their actual needs during Hajj and health situation
Spatial Appraisal of the Impacts of Drought on Agricultural Patterns in Karachi
Get PDFThis paper is aimed at studying the spatial changes in agricultural patterns practiced in the suburbs of Karachi, which is the most densely populated city of Pakistan with high food demands of the inhabitants. This study deals mainly with Physical factors primarily climatic indicators to observe and analyze the changes in the pattern of agricultural production and the types of crops in last 20-30 years. Variability of climate when coupled with anthropogenic factors play important role in the acceleration of problems for farmers. Trends of associated agricultural output observed in different years of high and low rainfall. This study has successfully demonstrated inquisitive approach by using published secondary data from governmental sources and ground verification in recent times. Temporal variation in biomass, was found dependent upon pattern of rainfall and temperature etc. Study reveals that there are clear signs of desertification and drought in the study area