JBAS Articles
JBASV8N2A64-Exponential Sum Modeling of Reswick and Rogers Pressure-Duration Curve: A New Analysis and Model
Journal of Basic and Applied Sciences - Volume 8 Number 2
Exponential Sum Modeling of Reswick and Rogers Pressure-Duration Curve: A New Analysis and Model
Oscar A. Linares, Darko Stefanovski and Raymond C. Boston
http://dx.doi.org/10.6000/1927-5129.2012.08.02.64
Abstract: Reswick and Rogers model is not valid for predicting the effects of short- and long-time tissue exposures to contact pressures because it lacks intercepts. A different model, without those asymptotic properties, that could fit the shape of the curve well, could potentially provide useful information. We used modeling to test the hypotheses that an exponential model could fit Reswick and Rogers pressure-duration curve, and, if so, to determine the order of the best fit exponential model. Up to four exponential sum models were fit. Three exponentials provided the best fit [Weighted sum-of-squared residuals 72, Akaike Information Criterion 89, r=0.997]. Thereby identifying three homogeneously distinct anatomical pressure-load containing tissue compartments: skin, fat, and muscle. A fourth compartment, bone, could not be identified because of limited resolution of the data. Our results suggest that the fat pressure-load containing compartment may play an adaptive compensatory preventive role in response to pressure loads—“a cushion effect.” Exponential sum modeling of pressure-duration curves provides a new approach for studying the dynamics of compression in normal and disease states in humans, and it may be useful for practical application at the point-of-care to assist with prevention and treatment of pressure ulcers.
Keywords: Nonlinear regression, curve fitting, parameter estimation, modeling, pressure sores, pressure ulcers, wounds, pressure-duration curve, SAAM, WinSAAM.
JBASV8N2A65-Dosimetric Evaluation and Verification of External Beam 3-D Treatment Plans in Humanoid Phantom Using Thermoluminescent Dosimeters (TLDs)
Journal of Basic and Applied Sciences - Volume 8 Number 2
Dosimetric Evaluation and Verification of External Beam 3-D Treatment Plans in Humanoid Phantom Using Thermoluminescent Dosimeters (TLDs)
Rizwana Siddique, Zaheer Uddin and Muzaffar Hussain
http://dx.doi.org/10.6000/1927-5129.2012.08.02.65
Abstract: Dosimetric 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.
Keywords: Thermoluminescent (Tlds) Dosimeters, anthromorphic phantom, vitro Dosimetry, vivo Dosimetry, Linear accelerator.
JBASV8N2A63-Effect of Application of Plant Growth Regulators on Earias vittella (Fabricius), Infestation and Yield Components of Cotton
Journal of Basic and Applied Sciences - Volume 8 Number 2
Effect of Application of Plant Growth Regulators on Earias vittella (Fabricius), Infestation and Yield Components of Cotton
S. Shahzad Ali, G.H. Abro, M.A. Rustamani and Shafi Mohammad Nizamani
http://dx.doi.org/10.6000/1927-5129.2012.08.02.63
Abstract: Studies were carried out on the effect of plant growth regulators on bollworm infestation and plant growth of cotton under field conditions. New cotton variety (CRIS-134) was sown in randomized block design with seven treatments including control (check) and was replicated three times on May 22, 2004. Mepiquate chloride, Acetyl salicylic acid and Naphthalene acetic acid (plant growth regulators) were applied on 10th, 25th August and 9th September 2004.The results indicated that there was no significant effect of either removal of leaves and fruiting bodies of cotton plant and application of plant growth regulators on cotton plant height but significantly effect on volume of bolls and yield in comparison to control. Moreover, application of hormones significantly delayed the maturity of cotton. There was also significant effect of application of plant growth regulators on bollworm infestation compared with control treatments.
Keywords: Earias vittella (F.) infestation, Plant growth regulators, New cotton variety CRIS-134.
JBASV8N2A62-Insecticidal Efficiency of Intergeneric Recombinants between Bacillus thuringiensis and Bacillus subtilis Against Viability of Cotton Leafworm
Journal of Basic and Applied Sciences - Volume 8 Number 2
Insecticidal Efficiency of Intergeneric Recombinants between Bacillus thuringiensis and Bacillus subtilis Against Viability of Cotton Leafworm
Saad A. Alotaibi
http://dx.doi.org/10.6000/1927-5129.2012.08.02.62
Abstract: Bacillus thuringiensis is the most widely applied biological insecticide and is used to manage insects that affect forestry and agriculture. This ubiquitous spore-forming bacterium kills insect larvae largely through the action of insecticidal crystal proteins and is commonly deployed as a direct bacterial spray. Moreover, this study aimed to measuring recombinant efficiency of recombinant bioinsecticides (Bacillus thuringiensis x Bacillus subtilis) against Spodoptera litoralis. For decades, the mechanism of insect killing has been assumed to be toxin-mediated lysis of the gut epithelial cells, which leads to starvation, or B. thuringiensis septicemia. In the present work, two strains of Bacillus strains belonging to two serotypes and four of their transconjugants were screened with respect to their insecticidal activity against lepidopterous cotton pest. Two strains of Bacillus were screened for their drug resistance to be used as a genetic markers to identify bacterial strains in the conjugation process. B. subtilis was found to be resistant to crystal violet and sensitive to hiconcil. Although, B. thuringiensis was found to be sensitive to crystal violet, except for it was resistant to hiconcil. Bacterial transconjugants isolated from conjugation between both strains were more resistant to both crystal violet and hiconcil. Two groups of crystals and spores have been isolated within Bacillus strains and their transconjugants. The results appeared a highly potent recombinant efficiency in reducing leaves consumption at 72h (crystals), 120h (crystals + endospores) and 144h (crystals + endospors). However, transcongugants B and c was more effective in reducing the rate of consumption at all different times of larval ages. The weight of surviving larvae feeding on leaves sprayed with recombinants of Cry, Cry + End. was markedly reduced especially at 48h of larval age. However, ransconjugants A, B and C appeared recombinant efficiency in reduced survival percentage of larvae at 96h, 120h, 144h and 168h in response to recombinants of both cry, cry + endospores. The same trend was also shown by transconjugant C at 48h and 72h in response to both recombinant bioinsecticides. The results indicated that recombinant endotoxin preparations containing crystals + endospores was more effective against Spodoptera litoralis than that containing crystals.
Keywords: Bioinsecticides, Recombinant efficiency, Insecticidal activity, Recombinants, Spodoptera littoralis.
