Vol. 21 Issue 1

K Adwan
We report on a study of 35 methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates collected between February and May 1998 from 4 different hospitals in Northern and Southern Palestine. The isolates were recovered from infection and carriage sites of patients and hospital environmental samples. The arbitrarily primed PCR (AP-PCR) method with two primers appears to be a useful tool, provides a fast and simple method for genetic analysis of MRSA infections and allows us to differentiate 22 different AP-PCR patterns. The major cluster, however, sharing common AP-PCR as well as a common PFGE pattern, represented 34% of all MRSA isolates. Isolates of this cluster were spread throughout the neonatal and intensive care units of Rafidya hospital during the entire period. In addition, these isolates were distributed in the southern part of Palestine as well

RM Khalil and F M Al-Nowaiser
Corrosion protection of metals and alloys in many industrial products is increasingly important from an economic and environmental point of view. Numerous chemical compounds have long been known as substances that influence the kinetics of electrode processes on which corrosion depends. Some of these compounds are found to retard electrode reactions and are termed inhibitors. The ability of the selected thiocyanate compounds as corrosion inhibitors for aluminium metal have been measured. The rate of corrosion was measured using weight loss, gas evolution and electrochemical techniques.

A. A. Malki
Profound changes are occurring in medical practice due to research, new discoveries, technological advances and different policies. The current and future changes are having a great impact on cost, health care services and ethics. Medical practitioners need to have enough knowledge of ethics to be able to practice their growing practical and research responsibilities with fairness and pride. The aim of this paper is to evaluate the abilities of a group of practitioners to explain ethics and their applications. Twenty medical practitIOners responded to a questionnaire distributed to them while attending a course on ethics, research and scientific writing. The results showed that the majority of the candidates were able to explain the meaning of ethics. There were deficiencies concerning research, authorship and writing. None of the candidates mentioned the impact of current changes and future developments on ethics in health care and research. There is a great need to expand on the knowledge and practice of ethics among health care professionals.

F FM Al-Sunni
We make use of the celebrated Kharitonov theorem to come up with a design procedure for the stabilization of uncertain systems in the parameters using low order controllers. The proposed design is based on classical design methods. A Non-Linear Programming (NLP) approach for the design of higher order controllers is also presented. We present our results and give illustrating examples.

A. A. Ammar, E.M. Abdelrahman, H. Hassanein and K.S. Soliman
The area studied, Gabal Um-Rabul, is located in the northern part of the Eastern Desert of Egypt. It is covered by different varieties of rock formations, including successions of basement and sedimentary rocks. The contact zone between them is considered as an unconformity contact. The area under consideration was included in an airborne gamma-ray spectrometric survey which was conducted by the Aero-Service Division, Western Geophysical Company of America in 1984. The present study deals with the interpretation of these aero radio spectrometric survey data, using conventional and modern statistical methods of analysis, in addition to reinvestigating the different mapped lithologies and considering them as interpreted radiometric lithologic (IRL) units. In this study, the geological map of the area was considered as a base for the radiometric lithologic interpretation of the data. The correlation between aeroradiospectrometry and lithology was conducted in two ways: the first one took into consideration the original lithological units, while the latter took into account the IRL units. The resultant interpreted radio lithologic unit (IRLU) map shows that, the study area contains four basement rock units and five sedimentary formations with various T.C radiometric levels and different radio element concentrations.

A. M. AbdelKarim
Amphiboles and biotites from some calcalkaline granitoid rocks ranging in composition from quartz-diorite (QD), through tonalite (TON), granodiorite (GD) to monzogranite (MGR) exposed at Wadi Akhdar Wadi El-Sheikh area have been analysed for major, trace and REE. Both the amphiboles and biotites cover a wide compositional range which reflects the magmatic evolution of their host rocks. The amphiboles belongs to the calcic-type, ranging from magnesio-hornblende in QD and TON, actinolite hornblende in GD, and actinolite in MGR. Biotite varies from 45 to 64 mol % phlogopite and classified as Fe-rich in QD, TON and GD and Fe-poor lepidopmelane in MGR. The proposed conditions of crystallization range from <1-3Kb and 650°-850°C for the amphibole and a lower pressure and 800-600°C for the biotite equilibrium Generally, the amphibole and biotite are characterized by an increase in Si, Fe, K and HFSE, a decrease in Ti, Ca, Mg and the third transitional element contents relative to Fe/(Fe+Mg) ratios. They also show a good parallelism with the successive enrichment of both the total REE contents and negative Eu anomalies, suggesting a progressive crystal fractionation from the more mafic melt to constitute the felsic QD- TON-GD-MGR crystallization trend. The examined amphiboles and biotites from Wadi Akhdar-Wadi El-Sheikh granitoid complex chemically similar to those from the orogenic calcalkaline (L-type) suites

Ibrahim M. Al-Helal and Ibrahim M. Al-Musalam
This research was conducted to study the effect of shading materials on greenhouse environment including inside temperature and relative humidity, and water and electricity consumption for cooling under Riyadh conditions. The study was performed on five greenhouses cooled by the fan and pad evaporative cooling system. The greenhouses were covered with single layer polyethylene. Four greenhouses were shaded with green plastic nets on the outside surfaces of covers. Shading levels were 55%, 65%, 70% and 80% according to the factory specifications. The fifth greenhouse was without shade for the purpose of comparison. Experiments were performed in two periods: the first period was from October 1 to October 30, 2000 (moderate summer conditions), and the second period was from July 16 to July 24, 2001 (extreme summer conditions). The results indicated that shade had no significant effect on inside air temperature during moderate conditions (P=0.05). But, inside relative humidity with shading levels of 55%, 70% and 80% was significantly higher than that without shade. During extreme summer conditions, shade significantly reduced air temperatures and increased relative humidity The 80% shade significantly reduced the consumption of water and electricity during moderate conditions by 16% and 19.3%, respectively. The 70% shade significantly reduced the consumption of electricity by 12.7%. Shade had no significant effect on the consumption of water and electricity during extreme conditions (P=0.05). It was shown that water and electricity consumption during extreme conditions were higher than those of moderate conditions. The increase rate of water consumption ranged from 79 to 112%, while consumption of electricity increase ranged from 12.7 to 36%.

M.S. Abido and M.S. Kurbaisa
Current status of Syrian Juniper forests in Assal Al-Ward ranges of the Anti-Lebanon Mountains was assessed. Autecology and synecology of Juniperus were characterized. Species parameters were assessed in 42 sites of various exposures and altitudes using the distance method and line transect techniques. Results obtained showed significant differences in Juniper density among sites of different exposures. Data suggested that the lowest level of species distribution was 1880 m altitude. Average Juniper density, importance value and coverage were 28.76 trees/ha, 32.5% and 10.8% respectively. Juniperus excelsa M.-Bieb.(Cupressaceae) dominated the community, whereas associated species consisted of deciduous elements most important: Amygdalus orientalis Mill. (Rosaceae), A. korschynskii (Hand-Mazzetti) Bornm. (Rosaceae), Crataegus azarolus L.(Rosaceae). Prunus sp. (Rosaceae), Pyrus syriaca Boiss. (Rosaceae), Cotoneaster nummularia Fisch. et Mey.(Rosaceae), Acer hermoneum Bornm. et Schwer. (Aceraceae), Berberis cretica L. (Berberidaceae), and Rhamnus palaestina Boiss. (Rhamnaceae). Less important species include among others: Astragalus sp (Fabaceae). Artemisia sp.(Compositae), Salvia sp. (Labiatae) and Acantholimon sp.(Plumbaginaceae). Signs of environmental stress were apparent on Juniper trees and reflected mostly in declining the increment of annual growth rings which, averaged 3.73 mm. Juniper trees attained a height of 6.5m and averaged 80 cm in diameter. Age of trees was estimated at 225 years. Juniper communities have been neglected, misused, over felled, overgrazed and deliberately set on fire. This reduced the extent of the Juniper ecosystem and demoted its ecological value. It is suggested that a management plan be put in effect to insure the ecosystem sustainability and Juniper trees conservation.