As a result of rapid development and growth of populated areas in the Kingdom of Saudi Arabia, several high voltage power transmission systems operating at various voltages up to 380 kV have been put into service and flashover difficulties with insulators of these systems caused by pollution of different types have been experienced. In order asses the pollution behaviour of line insulators in the Western Region of the Kingdom, two insulator types (longrod and cap-and-pin) have been subjected to natural pollution at four selected localities for 100 days and 2 years periods, without voltage being applied. The naturally polluted insulators have been tested in the High Voltage Laboratory of King Abdulaziz University. The investigation has shown that heavy pollution can accumulate on the insulators operating in Jeddah areas for over two years and the tested longrod insulator which is used in some part of the system can safely be used for years without any preventive measure. The cap-and-pin type appeared to be more appropriate for the region and leakage current recorder has been recommended for a better estimation of the insulator cleaning period.

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The importance of concentric handling of cylindrical objects is stressed. Reliability of clamping is underscored as a criterion in gripper design. The need to develop grippers that are rugged, compact, and which are able to apply large grasping forces, in addition to satisfying the requirement of concentric gripping of cylindrical objects is emphasized. A pneumatically actuated, force-intensifying six-link gripper is introduced that also features concentric gripping. Optimization of the configuration of the gripper is described, and results are discussed. It is concluded that the optimized gripper possesses favorable features, when compared to the initial solution, as regards its operational range as well grip-force intensification characteristics. Several finger configurations for the gripper are addressed.

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The aluminium uptake by rat isolated hepatocytes and its effect on oxygen uptake has been investigated. The hepatocytes aluminium content has elevated after incubation in medium containing aluminium-transferrin (Al-tf) or free aluminium (ultrafiltrable). The free aluminium (Al) influx to the cell is two times more than aluminium bound transferrin. The aluminium uptake from transferrin depends on the degree of saturation of transferrin depends on the degree of saturation of transferrin with AI. Aluminium transferrin complex and ultrafiltrable fractions of aluminium lead to the reduction of oxygen uptake by 18 and 32 percent respectively. Cellular uptake of aluminium and its effect on mitochondria function has been discussed.

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In the present work data on litter production and some physico-chemical parameters, such as dissolved oxygen, salinity, pH and temperature, is presented and discussed. Study area exhibits monospecific conditions and Avicenia marina (Forsk.) Vierh. is the sole representative species. Litter production fluctuates with seasons. 74% of the total production is contributed through the leaf-fall. Remaining 26% is comprised of twigs, fruits and flowers. Total amount of production is 3.71 ± 0.36 t. ha-1. Pattern of variation is dissolved oxygen content was similar at the two sites studied except for the magnitude of values which were consistently low at the back waters. Salinity was high as that sea water indicating low influx of fresh waters. PH was generally alkaline and temperature varies with seasons.

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The effect of small doses of bromocriptine, a dopamine agonist, on morphine-induced analgesia, tolerance and dependence was investigated in mice. Bromocriptine at dose of 0.04 and 0.08 mg/Kg did not affect the base line of tail flick latency of mice but dose-dependently potentiated the morphine analgesia. Pretreatment of mice with 5 mg/Kg of sulpiride, a D-2 antagonist, not only blocked the effect of 0.08 mg/Kg of bromocriptine but also antagonized the morphine analgesia. Daily injections of 10 mg/Kg of morphine rapidly developed tolerance to the analgesic effect in control animals. Daily combined treatment of bromocriptine with morphine supperssed the development of tolerance to morphine suppressed the development of tolerance to morphine analgesia in a dose-dependent manner. However, in the animals daily treated with bromocriptine (0.08 mg/Kg) plus sulpiride (5 mg/Kg), the development of tolerance to the morphine analgesia was not significantly modified. Acute dependence was induced by administration of 100 mg/Kg of morphine. Administration of bromocriptine 30 min before naloxone significantly decreased the naloxone ED50 for inducing jumping in mice. Coadministration of sulpiride with bromocriptine to potentiate the withdrawal syndrome of morphine dependence.

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Aflatoxins at level 250g/kg was included in the diet of three different strains of commercial broiler chicken designated as A, B and C and growth of twenty chicks/group (control as well as treated), was observed for 3 weeks. Compared to controls, at least in two of the strains, significant weight loss was noted. In strain "A" and "C” respectively 33.3% and 13.2% weight loss was recorded, indicating strain difference in chicks to aflatoxin susceptibility. Use of broiler strains resistant to aflatoxin would help in minimizing this problem.

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Penicillium crustosum Thom was succesfully used for sterols production using clarified beet molasses (BM) as the sole carbon source. High yields of sterols and ergosterol were accumulated in the presence of some streol precursors (squalene or pyruvate). A cheep and economic fermentation medium that favoured maximum streol and ergostrerol yileds was found to contain the following ingredients (g/1): H2SO4-treated BM, 90; corn steep solid, 30; initial pH 7.0 and incubation period for 8 days. The GLC analyses revealed the formation of ergosterol (62.1%), stigmasterol (17.2%), fungisterol (16.4%), and lanosterol (4.3%).

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The toxicological studies performed on Bacillus isolate 310109 isolated from the Iskenderun region of Turkey, by experimental infection of mice have revealed the absence of acute and prolonged toxicity. All acute and prolonged toxicity tests produced negative results with all the various routes, subcutaneous, intraperitoneal, intravenous injection oral (gavage), inhalation and percutaneous application and eye irritation test, using 2x108 bacteria per/ml suspension for each inoculation. Neither pathological symptoms nor mortality were observed. The behaviour and weight gain of the experimentally infected animals were within the normal range and close to those of the control animals.

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Mammalian toxicity tests were carried out on mice and guinea-pigs with Bacillus thuringiensis israelensis number 330211, isolated from the Icel region of Turkey. Test animals were injected by various routes including subcutaneous intraperitoneal, intravenous, oral, percutaneous, inhalation and eye irritation test, using stock suspension of 2X108 per/ml bacteria for each inoculation. None of the animals showed any evidence of illness and behaviour, growth, average organ and body weights were normal.

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A number of functionalized polymer containing pesticide active groups have been discussed for the purpose of developing ideal controlled release formulations for herbicides, molluscicides and wood preservation. These polymers have been prepared either by polymerization of active monomers or by chemical modification. The active groups are attached directly to the polymer backbone or through a spacer group via covalent or ironic bonds. The results obtained from the hydrolysis studies of these functionalized polymers, indicated that several factors appear to be major govering the rates of release of active moieties. These factors include the environmental conditions as well as the effects of polymers compositions, properties and chemical structures such as the degree of crosslinking, the type and ratio of comonomer, the hydrophilicity, the spacer group, the type of the pesticidepolymer chemical bonds, and the simulated conditions necessary to increase the duration of the activity such as pH and temperature.

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During a 10 year period ending in July 1988, 66 patients with cardiac injury were operated at the department of Cardiovascular Surgery at Cukurova University, Faculty of Medicine. Sixtythree patients (95.45%) were male. Their ages ranged between 13 and 59 years. Fifty-four patients (81.81%) had stab wounds and nine (13.63%) gunshot wounds. Three patients (4.54%) had blunt trauma. Thirteen patients (16.69%) were in the terminal stage, 37 patints (56.60%) were in a shock state and 16 patients were hemodynamically stable (24.04%) upon hospitalization. Thirty-two patients (48.48%) had evidence of cardiac tamponade and 18 patients (22.27%) were in hemorrhagic shock at the initial examination. Overall mortality was 16.66 percent(11/66). Four of 54 patients (7.40%) with stab wounds died in comparison to 5 out of 9 patients (55.55%) with gunshot wounds (P<0.05). Mortality for the patients in terminal stage was 30.76 percent (4/13) and 13.51 percent (5/37) for those in shock stage. On the other hand, mortality rate in patients with cardiac tamponade was 9.37 percent (3/32) and 33.93 percent (6/18) for the patients with hemorrhagic shock (P<0.05).

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Lyofilized amniotic membrane in 33 patients and teflon sheet in 20 patients was used as lining in tympanic cavities. Only the patients whose contralateral ears were normal were included in the study and these contralateral ears served as control group. The patients were reexplored 1 year later and the newly formed mucosa examined histologically. The middle ear pressures of the amnion lined and teflon lined ears were measured and compared statistically with each other and with the control group. Our experience shows a normal appearing mucosa in amnion lined group on reexploration 1 year later compared to the thick, less vascularised mucosa in teflon lined group. The mobility of the tympanic embrane was better in amnion lined ears (66.6%) than teflon lined ears (60%) although the difference was not found significant statistically. In the light of these findings it can be said that liofilized human amnion membrane is a good biologic material which can be used for lining the tympanic cativies.

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Twenty-six patients with recurrent aphtous stomatitis were studied with respect to zinc and copper deficiency. Their mean serum zinc levels before treatment was 78.23 ± 2.64 g/dl and after treatment 100.31 ± 3.56 g/dl (p < 0.05). Zinc content of 1010 erythrocytes was 11.35 ± 0.41 before and 13.54 ± 0.50 g after treatment (p<0.05) while serum copper levels were maintained almost at the same level (p>0.05). Of the total series, before treatment, serum Zn levels in 20 patients, serum copper levels in 5 patients, and Zn contents of 1010 erythrocytes in 18 patients were found below normal levels. Following one, two, and three months of treatment serum Zn levels and Zn contents of 1010 erythrocytes of patients rose parallel to the improvement in clinical findings. A significant remission was observed after the 3rd month of treatment in 22 (84.6%) of 26 patients. The differences between pre-treatment and of monthly evaluation following treatment in mean serum Zn levels and Zn contents of 1010 erythrocytes were statistically significant (p<0.05).

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Blood flow to anterior alveolar and platal mucosa in 7 patients and blood flow to anterior alveolar mucosa and skin of upper arm in 7 other patients were measured by intramucosal and intradermal (for skin) injections of 133Xe. Later mandibular vestibuloplasty with mucosal grafts in the first and with skin grafts in the second group was performed. During the postoperative period, the patients were followed by clinical observation, and by blood flow measurements for 6 weeks and 1 month respectively. 133Xe clearance was measured on the 7th and 30th days, postoperatively. In normal subjects, the mean blood flows to alveolar and palatal mucosas were 49.2 ± 5.3 and 26.3 ± 3.6, respectively and to skin was 6.57 ± 0.88 ml/100 g/min. Mean blood flow to mucosal graft was 34.7 ± 5.4 and 37.9 ± 3.9 ml/100g/min on 7th and 30th days after the operation, respectively. The means of blood flow to skin grafts were 48.7 ± 5.1 and 39.6 ± 3.8 ml/100g/min on 7th and 30th days after the operation, respectively. These results were in agreement with clinical observations.

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In 12 cases with normal coronary angiogram and 29 patients with abnormal coronary angiogram, 15 mCi Tc-99m hexamibi and 2 mCi Tl-201 were injected during exercise on separate days and planar imaging was applied. A second injection of 15 mCi of Tc-99m hexamibi was performed with the patients at rest one day later. Rest Tl-201 scintigraphy was performed 3 to 4 h later following exercise imaging without a second injection. Quantitative assessment of both Tc-99m hexamibi and Tl-201 were performed in 205 left ventricle segments and coronary perfusion reserve (cpr) of each segment was calculated on Tc-99m hexamibi and Tl-201 studies, from exercise to rest. There was good correlation for the cpr of normal or abnormal myocardium with two radiopharmaceuticals Myocardial defect uptake was nearly identical, yielding agreement in 93.8% of the myocardial segments in patients with coronary artery disease (CAD) and 88.3% of the myocardial segments in normal patients. We conclude that Tc-99m hexamibi is a sensitive myocardial flow marker. However, a second injection was needed to asses regional cpr within this protocol.

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The potential of 99mTc-GP as a lung tumor scanning agent was reported. In this study, we adressed the question of whether 99mTc-GP can accumulate in various bone disease. 22 patients with various bone disease were studied by 99mTc-GP as well as by 99mTc-MDP. We report the results of the visualization and quantitation of 99mTc-GP uptake and a comparison with 99mTc-MDP. All bone pathologies demonstrated by 99mTc-MDP were also visualized with 99mTc-GP. Althoungh the target/nontarget ratios obtained by 99mTc-GP were inferior to those obtained by 99mTc-MDP, the differences were not significant for all kinds of bone pathologies (p>0.05). It was concluded that although 99mTc-GP can demostrate the bone pathologies; it is not as sensitive and specific as 99mTcMDP. The mechanism of 99mTc-GP uptake in bone pathologies is not clearly understood.

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