Bacterial wilt caused by Ralstonia solanacearum is a major production constraint of solanaceous crops in tropical and sub tropical areas of the world including Pakistan. Therefore the biology of this disease was studied to elaborate current status of bacterial wilt in the country. The disease was mainly found distributed in Punjab and Islamabad Capital Territory. R. solanacearum was found to be associated with tomato, pepper, brinjal and potato. High prevalence of the disease was noticed in pepper, especially sweet pepper. During the surveys, other diseases of solanaceous crops were observed i.e Verticillium and Fusarium wilt, root knot nematodes (Meloidogyne spp), Phytophthora rot (Phytophthora capsici), stem rot/southern blight of tomato (Sclerotium rolfsii), pepper leaf curl virus, bacterial blights (Xanthomonas compestris and Pseudomonas syringae). According to farmers, bacterial wilt has been present in some fields of Punjab province for the past 20 years where out breaks of the disease were observed during monsoon season each year. Most of the farmers were not aware about bacterial wilt symptomology and its causal organism. Most of the commercial varieties used by farmers were imported whose disease resistance information was not known. Bacterial wilt was found in areas with diverse soil, pH, temperature, relative humidity, rainfall and topographical patterns. Mostly wilt affected soils were alkaline, calcareous in nature. Based on biochemical, serological and host tests specified for the identification of R. solanacearum, out of 326 isolates 45 (13.8%) were found to be R. solanacearum. The tests further revealed that biovar 2 and 3 were more prevalent in Pakistan with 80 % of strains belonging to biovar 3. The predominant biovar associated with potato was biovar 2. Studies further revealed that the rest of strains obtained from tomato, sweet pepper, hot pepper and brinjal were mainly biovar 3. Majority of R. solanacearum strains were isolated from plant and soil samples. In addition, some biovar 3 strains were also found to be associated with sweet pepper and hot pepper seeds. The strains obtained from sweet pepper formed a distinct cluster (based on serological and pathogenicity tests) as compared to the rest of strains. Studies further indicated that soil inhabiting bacteria (Pseudomonas aeroginosa, Klebsiella pneomoniae, Pseudomonas entomophila) or possible phenotypic conversion affect detection of R. solanacearum from soil. Enrichment ELISA combined with PCR proved to be a useful tool for detection of R. solanacearum from soil. Local pepper varieties i.e Sanam, Sangri and Ghotki showed good resistance to bacterial wilt. On the other hand local tomato varieties Roma and Rio Grande, and imported commercial sweet pepper variety California Wonder was found to be highly susceptible to bacterial wilt. UW 585 (Phylotype 1 American strain) was significantly distinct from UW 371 (Phylotype 1 Asian strain). Asian strain GMI 1000 and American strain K60 were equally aggressive on all tomato varieties. Results of these studies will provide basis for improved diagnosis, monitoring of bacterial wilt and formulation of management strategies.
Background and Aim: Headache is a very common condition worldwide. Cervicogenic headache is a secondary type of headache. Dentistry requires both, the concentration and precision and dentists have to work in constricted zones for extended period of time so it is important to evaluate headache among dental population. The objective of this study was to screen Cervicogenic headache among dentists working in Lahore Medical and Dental College, Lahore.
Methodology: The Descriptive Cross-sectional study, of 6 months duration, was conducted on 125 dentists. The data was collected from Lahore Medical and Dental College, Lahore. Non-Probability convenience sampling technique was used. Dentists working for at least 2 years and more than 5 hours daily, with the known cases of headache were included and those who were diagnosed with any other condition that cause headache like acute sinusitis, High blood pressure etc. were excluded. Data was collected by using cervical Flexion Rotation test whose validity is 0.81. Data was entered by using Statistical package for Social Sciences (SPSS) version 21 and the same software was used for data analysis.
Results: The findings showed that, out of 125 dentists, 36.8% (n=46) were male and 63.2% (n=79) were female and cervical flexion rotation test was positive in 30.4% (n=38) dentists.
Conclusion: This study concluded that cervicogenic headache is present in 30.4% dentists working in Lahore Medical and Dental College.
This work focuses on the modeling and numerical approximation of population balance models (PBMs) for simulating dispersed systems, especially the batch crystallization pro- cess. Apart from applying the existing numerical schemes, new numerical techniques are introduced for solving these models efficiently and accurately. The effects of nucleation, growth, aggregation, breakage, and fines dissolution phenomena on the crystal size distri- bution (CSD) are investigated. An alternative quadrature method of moments (QMOM) is introduced for solving the single-variate length-based PBM incorporating simultaneous nucleation, growth, aggregation and breakage phenomena. In the proposed QMOM, or- thogonal polynomials, formed by lower order moments, are used to find the quadrature points and weights. To ensure better accuracy of the scheme, a third order orthogonal polynomial, utilizing the first six moments, is selected to calculate the quadrature points (abscissas) and corresponding quadrature weights. Therefore, at least a six moment sys- tem is needed to solve. This choice of polynomial gives a three-point Gaussian quadrature rule which generally yields exact results for polynomials of degree five or less. A mathe- matical model is derived for simulating batch crystallization process incorporating crystals nucleation, size-dependent growth and dissolution of small nuclei below certain critical size in a recycling pipe. Moreover, a time delay in the dissolution unit is also incorporated in the model. The dissolution of small crystals (fines dissolution) is helpful to further improve the product CSD. It withdraws and dissolve excessive fines from the quiescent zone of crystallizer which are generated during periods of high supersaturation. This ef- fectively shifts the CSD towards right and often makes the distribution narrow. A new numerical scheme is introduced for simulating this model. The method of characteristics, the Duhamel’s principle, and the QMOM are employed together to devise the proposed numerical scheme. Several test problems are considered and the numerical results are val- idated against available analytical solutions and the finite volume scheme (FVS). It was found that the suggested numerical methods have capability to solve the given models efficiently and accurately.