Vol. 8 Issue 1
Abdallah M. Al-Rashed and Neyamat Zaheer
We obtain a general theorem on the location of null-sets of certain types of abstract polynomials in vector spaces of arbitrary dimension (finite, or otherwise). This theorem generalizes Walsh’s two-circle theorem concerning the critical points of rational functions of the form f/g, where f and g are complex-valued polynomials of the same degree; and it offers an extension of Laguerre’s theorem on polar-derivatives
Salim S. Al-Showiman
Seeds of five date palm cultivars (Phoenix dactylifera L.) namely Barhey, Maktomey, Sekkeri, Fankha and Kasba, were chemically analyzed for their content of some organic and inorganic compounds. Qualitative phytochemical screening showed important contents. Fatty acids, sugars, minerals and other significant organic compounds were observed.
Aly M. El-Sayed, Mohamed A. Al-Yahya, Mahmoud M.A. Hassan
The essential oil of E. arabicus was prepared from the aerial parts and analyzed by capillary GC/MS. Several mono- and sesquiterpenoids were tentatively identified in this plant for the first time by mass spectral comparison with reference compounds. The activity of the oil against Staphylococcus aureus and Bacillus subtilis may predict some interesting antimicrobial agents in this Saudi plant.
Faig El Schami
The spring Ain bu Sukhanah is artesian in character and has an average discharge of (160 l/sec). The water reaches the spring along fractured beds of the underlying Miocene gypsum sequence. The spring water is brackish with the type of Ca-Sodium-Chloride. The hydro chemical composition of the spring water reflects an old marine genesis.
Mixing of spring water with the circulating meteoric water is reflected in the hydro chemical composition.
S. Ayyash and M. Rasas
Crop production in greenhouses in Kuwait is constrained in summer by the prevailing harsh weather conditions, characterized by high solar irradiance and ambient temperature, and scarce freshwater resources. The harsh weather conditions and inefficient evaporative cooling systems cause excessive water consumption for greenhouse cooling. It is shown that the ambient temperature has a particularly significant effect on water consumption, which varies exponentially with temperature. The efficiency of the cooling system has also a significant effect on water consumption. It is argued that substantial water saving can be achieved by improving the efficiency of the cooling system and controlling solar irradiance transmitted into the greenhouse.
J.S. Saif and A.H. Awad
The effect of the three phonon scattering on the phonon drag thermoelectric power of As and Sb doped Ge has been studied in the temperature range 2-20 K.
At very low temperatures, it is found that the effect of the Umklapp processes are very small and can be ignored while the Normal processes are in a good agreement with the calculated values up to 10K. Above 10K both kinds of scatterings should be included in the calculations.
The study has shown that the most important scattering mechanisms in such samples are the electron-phonon and the point-defects scatterings.
A.A. Fahad
Leaching of sodium was investigated in columns of loam and clay saline soils in relation to different methods and initial water content. Non-destructive measurement for the distribution of the applied radio sodium was made during the leaching course by gamma spectrometry. The results indicated that the method of leaching appeared the most important factor in altering the Na distribution. Based on the magnitude of the Na peak displacement with respect to water applied, the efficiency methods in leaching of the loam soil followed the order: simulated rain (SR) > continuous ponding (CP)> intermittent ponding (IP) at air dry and CP> SR>IP at both field capacity and near saturation initial water content. The results were reserved in the clay soil.
Pre-wetting the loam soil slowed down the movement of sodium. In the clay soil, no consistent effect on Na movement occurred with increasing initial water content. The efficiency in displacement was explained on the basis of the effective fraction of water participating in solute transport.
F.D. El-Nouty, A.A. Al-Haidary and M.S. salah
Effects of summer and winter season were studied in two groups of 15 non-pregnant Holstein cows. Each group included 5 dry cows, 5 high-yielders and 5 average-yielders. The rise in air temperature and temperature-humidity index (THI) during summer compared with winter caused a significant (p< 0.01) rise in rectal temperature (RT) and respiratory rate (RR) of lactating cows compared with the early morning, and in the high-yielders compared with the average-yielders. Diurnal rhythms in RT and RR were found in winter but not in summer. Productivity status was found to exert greater effect on plasma thyroid hormone levels than did the season. Regardless of season effect, thyroxine (T4) and triiodothyronine (T3) concentrations were significantly (p<0.01) lower in lactating cows than in dry cows. In summer, dry cows had higher T4:T3 ratio and blood glucose concentration compared with winter season, meanwhile the lactating cows showed an opposite trend. Among the two lactating groups, T3 level was significantly (p< 0.01) reduced in the high-yielding cows only during the winter season. The decline in the milk yield of the high producing cows for each unit rises in THI, air temperature and RT were 0.92, 0.15 and 3 kg/day, respectively.
R. El-Ghareeb, N. Saber and L. Bidak
The study demonstrates spatial and temporal variations in the crude protein content in the organs of three desert species of different growth forms in five habitats in the northwestern desert of Egypt.
The crude protein content in the annual grass Cutandia dichotoma is higher than that in the perennial herb Plantago albicans and the perennial subshrub Helianthemum lippii. The ranges of variations in the crude protein content in the selected species are comparable to those of the important range species in other arid regions. The contents are higher than in some cultivated fodder crops and foodstuffs. The contents in the photosynthetic organs of the two perennial species are highest during the early vegetative stage and are lowest during the dormant stage.
The crude protein content in the selected species exhibits notable ranges of variation with habitat. In Helianthemum lippii, the content increases from 4.13% to 8.75% in old branches during summer as the total soluble salts increases from 0.36 mmhos/cm in the coastal dunes to 1.46 mmhos/cm in the transitional area between the ridge and the saline depression. It also increases from 7.05% to 8.31% in leaves and from 3.06% to 5.06% in roots as the total soluble salts increased from the first to the second habitat. An opposite trend is exhibited by the content of crude protein in Plantago albicans and Cutandia dichotoma.
Ahmad A. El-Oqlah and Fawzi M. Karim
On the basis of a study of 22 of 30 species representing 12 sections of Silene in Jordan, we find that the seed coats exhibit considerable anatomical diversity, particularly the exotesta and mestotesta. Equivocal relationships are demonstrated for species with essentially identical seed features and seed coat sculpturing. Outer layers of the seed appear to be more open to adaptive modifications than inner ones.