49 research outputs found
Groundwater Contamination in Jaffna Red Beds Mainly Focused on Nitrate and Trace Elements
The Jaffna peninsula is dependent on groundwater for all its water requirements andpredominantly for agricultural activities. Studies on effect of fertilisation and groundwaterpollution in such an area are of prime importance. Especially, nitrate rich drinking water ispotentially harmful to human health, particularly to infants. It is recommended that pregnantwomen and lactating mothers should limit nitrate consumption. According to the Jaffnahospital sources, people living in red bed area mostly affected by water bone diseases.Therefore, this study mainly focused on behaviours of nitrate and associated trace elements(Li, Cs, Cu, Sr, Zn, Mn, Fe, K, Mg and Na) in the wells around the red bed in order toinvestigate source and mobility.Physical parameters of water also can be determined the quality of water. The pH wasanalysed by using pH meter. The results were along the study area in WHO and SLS limit.Electric Conductivity is considered as an important water quality parameter in assessingdrinking and surface water. According to the SLS Standards, most of the sources had it abovethe permissible level. The source for the Salinity may be sea water intrusion in thisagricultural land area. Therefore, the water not suitable for the drinking purpose.Seventy randomly collected groundwater samples were analysed using atomic absorptionspectrometer (AAS, Varian 240). Results indicated that most of the wells were highlycontaminated with nitrate in red bed area than in the other regions. It was noted that, overdosage of fertiliser and agrochemicals cause for higher nitrate contamination. It is furtherobserved that the red bed in the area is unconsolidated and mainly formed by iron courtedsands with lower level of organic matter. This further concluded that nature of the red bedprovides favourable conditions for leaching nitrate to groundwater rather than retaining in thesoil. The trace elements such as K, Mg, Ca, Na, Sr, Li and Cu exceeded the permissible levelfor drinking water for all the wells. This may be due to sea water mixing with groundwaterthrough the groundwater flow or by wind spray. Especially, element Ca and Sr may haveaccumulated by weathering of shell fragments in the calcareous deposits in the area.Conversely element Cu may have leached from agrochemicals. However, Zn, Fe, and Bawere in lower concentrations. In general, there were significant correlations between theelements which clearly concluded that the sources for the contaminations are diverse andanthropogenic.Keywords: Fertilisation, Nitrate, Red bed, Groundwate
Mining the Vavilov wheat diversity panel for new sources of adult plant resistance to stripe rust
Multi-year evaluation of the Vavilov wheat diversity panel identified new sources of adult plant resistance to stripe rust. Genome-wide association studies revealed the key genomic regions influencing resistance, including seven novel loci
The speedup of distributed iterative solution of systems of linear equations
The main objective of this research is to study the performance of distributed solvers for large sparse systems of linear equations. The relationship between the speedup and the number of processors is the main characteristic of distributed computing for this study. -- Systems of linear equations can be solved using either direct or iterative methods. For large and sparse systems of equations, iterative methods are often more attractive than direct methods. In distributed implementations of iterative solvers, the number of operations are equally divided among the available processors with the intention that all the sections are processed concurrently (i.e., by different processors). -- The iterative approach repeats the following sequence of steps until the required convergence condition is satisfied: -- 1. distribute the current approximation to all the processors, -- 2. determine a new approximation to the solution, -- 3. collect parts of the new approximation and check the convergence conditions. -- The implementation is based on the message passing paradigm, which is used widely on certain classes of multiprocessor machines, especially systems with distributed memory. It is expected that this study will determine the optimal number of processors for distributed linear solvers
A randomised placebo-controlled trial of topical steroid in presumed viral conjunctivitis
Aims To assess whether topical steroids improve patient comfort compared with hypromellose in acute presumed viral conjunctivitis.Methods Patients presenting with acute follicular conjunctivitis, presumed viral in origin, were randomised to receive either dexamethasone 0.1% or hypromellose 0.3% drops four times daily for 1 week. At review after 5-7 days patients completed questionnaires on whether they thought the treatment had helped and on their level of discomfort. A physician assessed conjunctival hyperaemia using a grading scale.Results 111 patients were randomised: 56 received dexamethasone drops and 55 received hypromellose lubricant drops. Eighty-eight returned for review. Most patients (39/45 (87%)) receiving dexamethasone and most of those receiving hypromellose 30/43 (70%) felt that the treatment helped. Analysis of all responses showed a significant difference between treatments (p = 0.0248, rank sum test). No significant differences between dexamethasone and hypromellose arms were found in the patients' perceived level of discomfort or the physician grading of conjunctival hyperaemia. No patient experienced a serious complication.Conclusions There us now evidence to support the use of a short course of topical dexamethasone for patients presenting with acute follicular conjunctivitis presumed to be viral in origin. Where topical dexamethasone is prescribed we have not found it to be harmful
How the built environment matters in recovery after neurotrauma: a qualitative examination of first-person experiences across two inpatient settings
Architectural risk of buildings and occupant safety: an assessment protocol
Architectural risk of buildings relates to the possibility that technical and environmental elements of buildings interiors and outdoor spaces, may create dangerous situations for health and safety of occupants due to their engineering properties and their state of preservation, maintenance and use. Despite dangerous situations arising from architectural features of buildings are mentioned but undervalued in safety regulations, and a limited number of built environment aspects are currently analyzed in standard assessments of health and safety on work, many evidences demonstrate the strong relation between injuries or diseases of occupants and technical and environmental features of life and work environments. From this background, the study presents a Protocol for the Assessment of Architectural Risk (ARAP) for working environment proposed by Laboratory of Applied and Experimental Ergonomics of University of Naples Federico II (LEAS), with the Campania Chapter of INAIL, the Italian National Institute for Insurance against Accidents at Work. Main results of an application of the ARAP Protocol to an office building are also presented