Exponential Sum Modeling of Reswick and Rogers Pressure-Duration Curve: A New Analysis and Model
Oscar A. Linares, Darko Stefanovski and Raymond C. Boston
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.
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
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 9thSeptember 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.
Insecticidal Efficiency of Intergeneric Recombinants between Bacillus thuringiensis and Bacillus subtilis Against Viability of Cotton Leafworm
Saad A. Alotaibi
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 Bacillusstrains 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 litoralisthan that containing crystals.
Keywords: Bioinsecticides, Recombinant efficiency, Insecticidal activity, Recombinants, Spodoptera littoralis.
Effect of Different Photo Periods on the Biological Parameters of Chrysoperla carnea under Laboratory Conditions
Qadeer Ahmed, Raza Muhammad, Nazir Ahmad, Javed Ahmed, Shahnaz Naz, Hayder Ali and Nazia Suleman
Abstract: Many insects are known to give response in adaptive way for seasonal changes in day lengths. Photoperiod control’s many developmental responses and allows insects to survive periods of unfavorable environmental conditions. An experiment was conducted to study the effect of different photoperiod lengths on biological parameters of green lacewing, Chrysoperla carnea. Four different photoperiod regimes were selected with varying lengths of light/dark hours (8/16, 10/14, 24/0 and 0/24) at a constant 26±2°C temperature with 70 % RH (relative humidity) in the laboratory. Photoperiod regimes affected the development of C. carnea from egg to adult. In complete darkness (L: 0 D: 24), minimum egg laying, hatching, larval survival and adult emergence were recorded. Incubation period for eggs, larval period and pupal duration were also significantly longer in complete darkness as compared to other treatments 8L: 16D and 10L: 14D. Whereas, the treatment with complete light hours (L: 24, D: 0) resulted in maximum egg laying hatching, larval survival and adult emergence. The incubation period for eggs, larval and pupal duration significantly shortened as compared to other treatments.Sex ratios skewed towards female when full light hours were provided for development.
Keywords: Chrysoperla carnea, photoperiod regimes, hatching, larval survival, sex ratios.
Surgical Management of Congenital TEV in Children at PMC Hospital Nawabshah
Saeed Samo, Zulfiqar Soomro, Zamir Soomro and Mehtab Pirwani
Abstract: Introduction: Talipes equino varus TEV is one of the most common congenital anomaly. It is managed by some common ways i-e., conservative & surgical methods. Among surgical methods are Turco’s posterior medial release, posterior soft tissue release operation (Attenborough), four quadrant release (Mc Kay). Objective of this study was to determine the reliability of surgical option like postero medial release in children having congenital TEV.
Material & Methods: This study was carried out during the period from October 2002 to March 2005 in the Deptt. of Orthopaedics of PMCH Nawab Shah. The inclusion criteria were children 2 months to 30 months of age having moderate to severe club foot. Clubfoot secondary to some other disorder such as cerebral palsy, arthrogryposis multiplex congenital, myeldysplasia or DDH were not included in this study. The deformity was treated surgically in all cases by postero medial release. Follow-up period was one & half year.
Results: A total 57 patients were included in this study with the age range of 2 months-2.5 yrs with moderate to severe deformity. Forty two were male (73.7%) and 15 patients (26.3%) were female, seventeen patients (29.8%) had bilateral club foot while the rest the rest of 40 patients (67.1%) had unilateral deformity. Positive family history of club foot was in 10 patients (17.5%). Results were concluded on 57 patients who completed one & half year follow-up. Excellent results were observed in 41 patients (71.9%), good in 11 patients (19.2%), fair in 2 children (3.5%). No patients lost to follow up.
Conclusion: Children up to 30 months (2 months – 2.5 years) age with congenital TEV can be treated with surgery successfully.
Keywords: Talipes equino varus, Postero medial release, Deformity.
Use of Distally Based Sural Artery Flap to Manage the Soft Tissue Defects of Lower Tibia and Ankle
Saeed Samo, Zulfiqar Soomro and Zamir Soomro
Abstract: Objective: To present experience of soft tissue cover of lower one third of tibia and ankle treated by an orthopaedic surgeon without the presence of a plastic surgeon but of course, depending on the reliability of this flap.
Patients and Methods: Nineteen patients, fifteen males and four females, with soft tissue defect of lower one third tibia and ankle requiring soft tissue cover were treated from April 2002 to September 2005. The flap was outlined at the posterior aspect of junction of upper and middle 1/3 leg.
The pivot point of the pedicle was at least 5cm i.e., 3 fingers’ breadth above the lateral mallelous to allow anastomosis with the peroneal artery. Skin incision was started along the line in which the fascial pedicle would be taken. The sub dermal layer was dissected to expose the sural nerve, accompanying superficial sural vessels and short saphenous vein. The subcutaneous fascial pedicle was elevated, with a width of 2cm to include the nerve and these vessels. At the proximal margin of the flap, the nerve and the vessels were ligated and severed. The skin island was elevated with the deep fascia. The donor site defect was closed directly when the flap was less than 3cm wide. A larger donor site defect along with the pedicle was covered with a split thickness skin graft.
Results: All flaps except two survived. Most flaps showed slight venous congestion which cleared in a few days. There was no loss of split skin graft & none was lost to follow up.
Conclusion: Distally based Sural artery flap remains the choice for reconstruction of soft tissue defects of lower 1/3 tibia and ankle. The dissection is easy, quicker and can be done by an orthopaedic surgeon already involved in flap surgery; without the presence of plastic surgeon.
Keywords: Soft tissue defects, distally based sural artery flap, Lower third of tibia & ankle.
Effect of Some Micronutrients on Damage Compensation and Yield Parameters in Okra.
Syed Shahzad Ali, Wazhar Ali Pusio, Huma Rizwana, S. Shahbaz Ali, Shifarash Ghouri and S. Sohail Ahmad
Abstract: The effect of micronutrients on damage compensation and yield components of okra was investigated, using three foliar sprays (at 15 days interval) of Effective microorganisms (EM-1), Wokozim and Kissan Supreme Tonic (KST). Weekly observations on sucking complex (thrips, jassid, whitefly) and pod borers were carried out. The yield ha-1 of green pods was recorded to ascertain the compensation of the damage done by the insect pests. The damage done by sucking complex and borers was markedly compensated by the micronutrients, and okra pod yield in EM-1, Wokozim and KST sprayed plots were 10911, 9507 and 8948 kg ha-1, respectively as compared to 8034 kg ha-1 in control. The effect of micronutrients on crop growth and subsequently on sucking complex infestation was significant and thrips, jassid, whitefly and borer infestation was relatively lesser in plots sprayed with micronutrient as compared to the control. KST was most effective in damage compensation of sucking complex and borers with highest okra green pod yield (P<0.01), followed by Wokozim and EM-1 when compared with control.
Keywords: Okra, micronutrients, sucking complex, okra yield.
On the Spectral Expansions Connected with Schrödinger’s Operator of Continuous Functions in a Closed Domain
Abdumalik A. Rakhimov, Kamran Zakaria and Nazir Ali Khan
Abstract: Present paper is devoted to study of uniformly convergence of spectral expansions in a closed domain. We consider here as a spectral expansions eigenfunction expansions connected with one Schrodinger’s operator with singular potential in two dimensional domains with smooth boundary.
Keywords: Eigenfunction, Eigenvalues, Expansions, Regularization, Riesz means, Mean value formula, Singular potential, Boundary problem, Hamiltonian, Sobolev spaces.
Micro Vertical Axis Wind Turbine Design Integrated with Wind Accelerating Techniques
Abdul Latif Maghanhar, Saleem Raza Samo and Altaf Hussain Rajpar
Abstract: Power generation from natural wind is the crucial issue due to rapid depletion of non-renewable energy resources and their pollution demerits. Most observers agreed that long-term economic growth will require technical innovation to make wind energy more competitive with other forms of energy. One among the key trends is the push to improve productivity. Vertical axis wind turbines are capable of extracting power from wind regardless of direction of natural wind flow. Very less work is devoted to improve the characteristics of wind to make it more useable for power generation. Major portion of the research is related to the wind energy system design that caters the domestic needs. A micro vertical axis wind turbine system with integrated wind accelerating techniques is proposed. At the outer of the turbine a wind accelerating convergent duct with larger wind area is proposed, that will perform as a nozzle action to accelerate the natural wind when it strikes on the front half portion of the turbine blades. Proposed micro wind turbine is also integrated with satellite dish type parabolic structure, mounted at the top of the turbine. The parabolic concentrator surface is coated with sun rays reflecting mirrors, sunlight striking on paraboliod surface is directed to words a heat absorbing hollow cylinder, erected at the center of the paraboliod concentrator. Hollow cylinder is the path channel for air leaving the turbine. Air molecules passing through this channel will be heated up, moving rapidly up word creating momentum in air leaving from the turbine. Design of the proposed vertical axis wind turbine system integrated with wind accelerating techniques and experimental study of wind accelerating duct composed of various section is reported in this research work.
Screening and Characterization of Luminescent Bacterial Strain
Uzma Badar, Erum Shoeb, Komal Daredia, Durr-e-Shawar, Jameela Akhtar and Maqsood A. Ansari
Abstract: Several samples of sea water and sea organisms were collected for the isolation of luminescent bacterial strain. The samples were collected from Clifton, Hawksbay, fisheri at Landhi and Jeti at Korangi, Karachi, Pakistan, the sea organisms such as Crab, Prawn, Fish, Eel, Fish Gut, Electric Fish were collected. Three different media were used for enrichment of samples that is BOSS, Luminescent Agar (LA) and nutrient broth. A total of twenty one different bacterial strains were selected for further studies on the basis of different colonial morphologies. They were designated as DGU101 to DGU116, DGU221-DGU224 and DGU227. These strains were checked for luminescent and tolerance against antibiotics and heavy metal salts. Only one strain isolated from sea water (Clifton beach) designated as DGU227 showed luminescent on Luminescent Agar (LA) medium. It also exhibited multiple metal and antibiotic resistances. The two large plasmids were isolated from DGU227 which were more than 10 kb in size. The luminescence, growth, quorum sensing phenomenon of bioluminescent bacteria is affected by the presence of metal and antibiotics in environment, which act as inducer, and substrate in activating and enhancing these natural activities. Mostly Luminescent was observed after 24 hours of incubation it enhanced while growing in presence of antibiotic Ampicillin. The strain DGU227 was further identified by 16S rRNA gene analysis and exhibited 98% homology with Vibrio chigassi bacterial strain.
Keywords: Bacteria, luminescent, metal resistance, antibiotic resistance, plasmid, Vibrio chigassi.