Showing papers by "University of Jordan published in 1991"
TL;DR: A simplified review of the theory of paracrystallinity can be found in this paper, where the analytical procedure for the determination of the distortion parameter,ghkl, and evidence of the existence of the structure in various types of materials are included.
Abstract: It has been established that “microparacrystals” are the building blocks of materials in the intermediate stage between crystalline and amorphous. A simplified review of the Theory of Paracrystallinity will be given. The analytical procedure for the determination of the paracrystalline distortion parameter,ghkl, and evidence of the existence of paracrystalline structure in various types of materials will be included.g-values > 0 and < 15% characterize the world of paracrystalline materials, which range from catalysts (g ≃ 1%) to polymers (g ≃ 3%), graphites (g ≃ 6%), glasses (g ≃ 12%) and molten metals (g ≃ 15%). Extensive studies ofg and-N, the average number of netplane layers which build up the paracrystal, have led to a fundamental empirical relationα*=N 1/2 g ≃ 0.15. This relation implies physically that the growth of paracrystals in a particular material is controlled appreciably by the level ofg in the netplane structure. Examples on the impact ofg on the behaviour of materials will be given. Relationships betweeng, the crystallinity, and the mechanical properties in polymers will be discussed. The results of our recent investigations on high-modulus Kevlar fibres will be used to demonstrate these relationships.
83 citations
TL;DR: Data suggest that the hypotensive action of garlic juice may be due, at least in part, to a direct relaxant effect on smooth muscles.
66 citations
TL;DR: The data suggest that the volatile oil of R. officinalis leaves has a calcium antagonistic property and inhibited the contractions of rabbit and guinea pig tracheal smooth muscle induced by acetylcholine and histamine stimulation, respectively, in Ca(2+)-free solution.
62 citations
TL;DR: Two siblings with features of the rare Zimmermann-Laband syndrome are described and the major aspects of this and other eponymous syndromes that may be associated with hereditary gingival fibromatosis are discussed.
Abstract: Hereditary gingival fibromatosis is frequently an isolated condition of little consequence apart from a cosmetic problem and occasional associations with hypertrichosis and/or epilepsy. There are, however, several uncommon or rare eponymous syndromes described in which gingival fibromatosis can be a feature: these include the Zimmermann-Laband, Murray-Puretic-Drescher, Rutherfurd, Cowden and Cross syndromes. This paper describes two siblings with features of the rare Zimmermann-Laband syndrome and discusses the major aspects of this and other eponymous syndromes that may be associated with hereditary gingival fibromatosis.
58 citations
TL;DR: Hyperthermostable proteases were characterized from five archaeobacterial species and these proteases, which were found to be of the serine type, exhibited a preference for phenylalanine in the carboxylic side of the peptide.
Abstract: Hyperthermostable proteases were characterized from five archaeobacterial species (Thermococcus celer, T. stetteri, Thermococcus strain AN 1, T. litoralis, Staphylothermus marinus) and the hyperthermophilic eubacterium Thermobacteroides proteolyticus. These proteases, which were found to be of the serine type, exhibited a preference for phenylalanine in the carboxylic side of the peptide. The enzymes from Thermococcus stetteri and T. litoralis hydrolysed most substrates (peptides) tested. All proteases were extremely thermostable and demonstrated optimal activities between 80 and 95°C. The pH optimum was either neutral (T. celer, Thermococcus strain AN 1) or alkaline. The protease of Thermobacteroides proteolyticus was optimally active at pH 9.5. Zymogram staining showed the presence of multiple protease bands for all strains investigated.
55 citations
TL;DR: The first case of a congenital malignant melanoma arising in the eye of a newborn girl with a large pigmented ocular tumor, hepatomegaly, and multiple pigmented skin and choroidal lesions is reported.
Abstract: Twenty-three cases of congenital malignant melanoma have previously been reported. Here the authors report the first case of a congenital malignant melanoma arising in the eye. A newborn girl had a large pigmented ocular tumor, hepatomegaly, and multiple pigmented skin and choroidal lesions. The histopathologic diagnosis was of a malignant melanoma with hepatic metastases. The skin and choroidal lesions were considered to be congenital melanocytic nevi. The most plausible pathogenetic link between these two conditions was that the malignancy had arisen as a second-hit mutation within a choroidal congenital melanocytic nevus. Despite widespread metastases the baby, treated by surgery and chemotherapy, survives in good health, aged 2 years, 10 months.
43 citations
Journal Article•
TL;DR: The numbers of traumatized children in each of the low and middle socio- economic classes were significantly higher than those in the high socio-economic class.
Abstract: The purpose of this retrospective study was to analyse firstly the prevalence of firsty fractured permanent incisors, secondly their distribution according to age, sex and socio-economic class and thirdly the location of the trauma, in a population sample of schoolchildren from Jordan. The sample consisted of 3041 children aged 7-12 years enrolled in 6 public and private schools from the city of Amman and its outskirts. The prevalence of fractured permanent incisors was 10.5% (12.1% in boys and 8.8% in girls). The largest number of injuries was observed in the 11-12 years group (15.0%) and there was an increase of the prevalence of trauma associated with the increase of age. Significantly more boys suffered injuries than girls (P less than 0.01). The teeth most commonly injured were the maxillary central incisors (79.1%) and 85.2% of children sustained one fractured tooth only. The numbers of traumatized children in each of the low and middle socio-economic classes were significantly higher than those in the high socio-economic class.
35 citations
TL;DR: Four flavonoids isolated and identified from the Jordanian Varthemia iphionoides showed little or no activity against the bacteria Staphylococcus aureus, Bacillus cereus and Salmonella typhimurium while compounds 1 and 3 were much more active against F. solani, Aspergillus parasiticus and C. tropicalis.
Abstract: Four flavonoids 5,7,4′-trihydroxy-3,3′-dimethoxyflavone (3′,3′-di-O-methylquercetin) (1), 5,4′-dihydroxy-3,7-dimethoxyflavone (kumatakenin) (2), 5,4′-dihydroxy-6,7,8,-trimethoxyflavone (xanthomicrol) (3) and 5,7,4′-trihydroxy-3,6,3′-trimethoxyflavone (jaceidine) (4) were isolated and identified from the Jordanian Varthemia iphionoides. They have not previously been reported in this genus. The aqueous alkaline solution of these compounds showed little or no activity against the bacteria Staphylococcus aureus, Bacillus cereus and Salmonella typhimurium. Compound 2 was active against the fungi Fusarium solani and Candida tropicalis while compounds 1 and 3 were much more active against F. solani, Aspergillus parasiticus and C. tropicalis.
33 citations
TL;DR: The Permian Umm Irna Formation in central Jordan consists of a 60 m thick sequence of clastic sediments which can be divided into two fluvial sedimentary facies.
32 citations
TL;DR: In this paper, the free and forced vibrations of a uniform beam elastically restrained against rotation at one end and against translation at the other end, and carrying a lumped mass with rotary inertia and external loading at an arbitrary intermediate point, are analyzed.
30 citations
TL;DR: Data show that NH4+ was essential for adventitious shoot regeneration from pear leaf explants on White's (1943) medium, and Nitsch (1969) gave significantly better regeneration in most of the experiments.
Abstract: The effect of various basal salts media, containing different nitrogen levels on in vitro adventitious shoot regeneration from leaf explants of ‘Louise Bonne Panachee’ and ‘Seckel’ pear (Pyrus communis L.) were investigated. Among the different basal salt formulae tested, Nitsch (1969) gave significantly better regeneration in most of the experiments. Shoot regeneration was altered with different NH4+-N/NO3−-N ratios. The best regeneration was obtained when NH4+:NO3− was either 1:2 or 1:3 regardless of overall N concentration. In addition, these data show that NH4+ was essential for adventitious shoot regeneration from pear leaf explants on White's (1943) medium.
TL;DR: The late Cretaceous Amman Formation in central Jordan consists of cherts, porcelanites, dolomites and phosphorites with various limestones types as mentioned in this paper, it is subdivided into five mapable lithological units: Mixed Mineralogy Unit, Porcelanite Unit, Chalk Unit, Main Chert Unit and Phosphorite Unit.
Abstract: The late Cretaceous Amman Formation in central Jordan consists of cherts, porcelanites, dolomites and phosphorites with various limestones types. It is subdivided into five mapable lithological units: Mixed Mineralogy Unit, Porcelanite Unit, Chalk Unit, Main Chert Unit and Phosphorite Unit. The microfacies indicates a deposition within a shallow-marine inner epicontinental shelf environment ranging from supratidal to deep subtidal. The depositional model of the Amman Formation differs, therefore, from that of the Monterey Formation which is generally regarded as a model for a phosphorite-chertdolomite association formed in deeper outer shelf and slope environments. Cherts and porcelanites are of biogenic origin, they were formed by an early diagenetic replacement of lime mudstones and lime packstones.
TL;DR: In this article, the theoretical analysis and performance investigation of a single, as well as double, glazed box-type solar cooker with or without reflectors is presented. And the effect of those parameters on the cooker performance was studied.
TL;DR: In this paper, anhydrous butter fat was prepared by including heat grits, turmeric, rosemary, sage, rue and fennel at a level of 75 g dry matter kg−1 butter.
Abstract: Sheep's anhydrous butter fat as prepared by including separately heat grits, turmeric, rosemary, sage, rue and fennel at a level of 75 g dry matter kg−1 butter. The product as stored at room temperature in clear glass jars for a period of one year. The storage stabilities of the anhydrous butter fat samples ere compared ith a control and ith a sample treated ith a 1:1 mixture of BHA and BHT at a level of 0.25 g kg−1.
Both storage time and type of treatment had highly significant effects (P⩽0.01) on the peroxide value and free fatty acid content of the product. None of the treatments succeeded in keeping the peroxide value belo 5 mEq O2 kg−1 beyond the fourth month of storage. The BHA-BHT mixture and rosemary helped extend the peroxide induction period to 10 and 6 months respectively.
Turmeric and heat grits ere as effective as BHA-BHT in controlling the oxidative rancidity during the first four months of storage. The rest of the herbs exhibited a pro-oxidant effect throughout the study hen they ere used separately. In a second experiment, some cases of positive synergistic interactions ere observed beteen turmeric and heat grits on one hand and the herbs used in the study on the other. This pattern as not regular as negative interactions ere also observed in some other cases.
Free fatty acid content of all the samples remained belo 10 g kg−1 as oleic acid; hoever, fennel had a significant (P⩽0.05) effect on controlling the evolution of free fatty acids.
TL;DR: The effects of an ethanol extract of Ferula sinaica roots on the smooth muscles of rabbit and guinea pig were tested in vitro using isolated segments of intestine, trachea and aorta and the inhibitions were concentration-dependent and reversible.
TL;DR: The Umm Ishrin Sandstone Formation as discussed by the authors consists of a quartz arenite facies and a subordinate heterolithic facies of siltstone and mudstone with sandy lenses.
01 Jan 1991
TL;DR: Data suggest that this Peganum Harmala Seeds Extract has Antispasmodic, Anticholinergic, Antihistaminic and Antiadrenergic Effects.
Abstract: The Effects Of An Aqueous Extract Of Peganum Harmala Seeds On The Smooth Muscles Of Rabbit and Guinea Pig Were Tested In Vitro Using Isolated Segments Of Intestine, Trachea and Aorta. The Extract Inhibited The Spontaneous Movement Of The Rabbit Jejunum and Guinea Pig Ileum and The Contractions Of Rabbit Jejunum and Guinea Pig Ileum Induced By 10−4M Acetylcholine Stimulation. The Extract Also Inhibited The Contractions Of Rabbit Tracheal Smooth Muscle Induced By 10−4M Acetylcholine Stimulation and The Contractions Of Guinea Pig Tracheal Smooth Muscle Induced By 10−4M Histamine Stimulation. Furthermore, The Extract Inhibited The Contractions Of Rabbit and Guinea Pig Aortae Induced By 10−4M Norepinephrine Stimulation. These Inhibitions Were Concentration-Dependent and Reversible. These Data Suggest That This Seed Extract Has Antispasmodic, Anticholinergic, Antihistaminic and Antiadrenergic Effects.
TL;DR: The case of the sudden unexpected death of a 21-year-old man due to embolization of segments of an aortic valve papillary fibroma to the left main and anterior descending coronary artery is presented.
Abstract: The case of the sudden unexpected death of a 21-year-old man due to embolization of segments of an aortic valve papillary fibroma to the left main and anterior descending coronary artery is presented. The literature regarding cardiac papillary fibroma is reviewed with particular reference to those cases associated with sudden death.
TL;DR: In this article, the physical aspects of yielding, fracture and dynamic relaxation of polypropylene-based composites reinforced with talc filler are studied, and the yield stress of the composites showed temperature and strain rate dependence described as a rate activated yielding process.
TL;DR: Preovulatory lobster oocytes were mechanically removed from follicles and fertilized in vitro with sperm from the vas deferens of males or the seminal receptacle of females and fixed for ultrastructural analysis at various times after insemination.
TL;DR: Glomus mosseae 2 increased the shoot growth of beans, broadbeans and chickpeas by 52, 117 and 190%, respectively, and no relation was found between shoot growth and the degree of mycorrhizal infection.
TL;DR: The effects of an ethanolic extract of Ferula sinaica roots on the uterine smooth muscles of rats and guinea pigs were tested in vitro using isolated uterine horns to suggest that this plant extract may have some antioxytocic potential.
TL;DR: Results indicate that the hypoglycemic activity of an aquous decoction of plant arial parts of E. creticum caused significant reductions in blood glucose concentration when given orally.
Abstract: E. creticum has been used in folk medicine in Jordan as a remedy for scorpion stings in the rural areas and as a hypoglycemic agent. The hypoglycemic activity of an aquous decoction of plant arial parts ofE. creticum was tested in normoglycemic and streptozocin-hyperglycemic rats. Results indicate that those extract caused significant reductions in blood glucose concentration when given orally.
TL;DR: Systematics, distribution and ecology of 4 lizards of Jordan were studied: Uromastyx aegyptius microlepis, Lacerta laevis kulzeri, lacerta trilineata israelica and Chalcides guentheri, all of which are new for Jordan.
Abstract: Systematics, distribution and ecology of 4 lizards of Jordan were studied: Uromastyx aegyptius microlepis, Lacerta laevis kulzeri, Lacerta trilineata israelica and Chalcides guentheri. All these species are new for Jordan. A revised list of the lizards of Jordan is given as an appendix.
TL;DR: Black (BPE) and clear polyethylene mulches (CPE), 0.08 and 0.06 mm thick, respectively, were compared for their effectiveness for soil solarization over three seasons during 1986–1989 in weedy fields to find out which species seemed to be enhanced by solarization.
Abstract: Summary:
Black (BPE) and clear polyethylene mulches (CPE), 0.08 and 0.06 mm thick, respectively, were compared for their effectiveness for soil solarization over three seasons during 1986–1989 in weedy fields. Solarization for 6 weeks reduced weed growth and enhanced crop yields. However, further mulching with BPE after solarization with either BPE or CPE gave the best results. Not all weeds were sensitive to solarization. Some weed species were completely controlled; others were reduced to varying degrees; yet other weed species seemed to be enhanced by solarization. Solarization without further mulching was no better than farmer-practice in reducing weed growth or in increasing crop yield. Weeds required further removal after the middle of the growing season. Any soil disturbance after solarization reduced the weed control effect of solarization. Crops grew best in plots after solarization with BPE if they were planted in the same mulch after it was perforated.
Resume:
Des mulchs de polyethylene noir (BPE) et de couleur clair (CPE) d'une epaisseur de 0,08 et de 0,06 mm respectivement ont fait l'objet d'une etude comparative d'efficacite en matiere de solarisation du sol pendant 3 saisons (1986–1989) au sein de champs enherbe's. Une solarisation d'une duree de 6 semaines a reduit la croissance des adventices et ameliore les rendements. Cependant, la poursuite du ‘mulching’ avec BPE apres solarisation avec soit BPE soit CPE a donne les meilleurs resultats. Toutes les mauvaises herbes n'etaient pas sensibles a la solarisation. Certaines especes ont ete completement detruites; d'autres ont ete reduites a des niveaux variables; cependant d'autres especes semblent avoir ete stimulees par la solarisation. La solarisation sans poursuite du mulching ne s'est pas averee etre meilleure que la pratique habituelle tant sur le plan de la croissance des adventices que des rendements. Les adventices ont exige une destruction apres le milieu de la saison de croissance. Tout derangement du sol apres solarisation a reduit l'effet herbicide de la solarisation. Les cultures ont mieux pousse dans les parcelles soumises a solarisation avec BPE si elles etaient plantees dans le meme mulch apres perforation.
Zusammenfassung:
Uber die Vegetationsperioden 1986–89 wurden schwarze (BPE) und durchsichtige (CPE) Polyethylenfolien von 0,08 bzw. 0,06 mm Starke in Hinblick auf ihre Wirksamkeit fur die Solarisation gepruft. Eine Einwirkung uUber 6 Wochen verringerte den Unkrautwuchs und vergroserte die Ertrage. Eine weitere Abdeckung mil BPE nach der Solarisation sowohl mil BPE als auch CPE ergab jedoch die besten Ergebnisse. Nicht alle Unkrautarten waren empfindlich fur die Warmeeinwirkung: Einige Arten wurden voll-standig bekampft, andere verschieden stark reduziert, und wieder andere schienen gefordert zu werden. Die o. a. kurze Solarisation war nicht wirkungsvoller als normale Unkrautbe-kampfungsmasnahmen, so das gegen Mitte der Vegetationsperiode eine weiter Bekampfung erforderlich war. Jegliche Bodenbewegung nach der Solarisation verschiechterte ihre unkrautbekampfende Wirkung. Die Kultur-pflanzen wuchsen am besten, wenn sie nach der Solarisation mit der BPE-Folie in die Folie hineingepflanzt wurden.
TL;DR: In this article, the long-term environmental pollution in Jordan, thirty two adipose tissue samples were analyzed for 15 Organochlorine Compounds using the capillary GC-ECD.
Abstract: To study the long-term environmental pollution in Jordan, thirty two adipose tissue samples were analysed for 15 Organochlorine Compounds using the capillary GC-ECD. The results were discussed in terms of clinical aspects and in terms of environmental and hygienic effects. To explain the sources of pollution, the major fat-containing food stuffs usually used in Jordan were analysed. It has been found that most of the imported foods are contaminated, especially with heptachlor and heptachlorepoxide.
TL;DR: The patterns of smoking in Jordan were determined in a sample of 3489 subjects representing various strata of society and it is apparent that a rigorous antismoking campaign is needed.
Abstract: The patterns of smoking in Jordan were determined in a sample of 3489 subjects representing various strata of society. The sample included 2103 students and 1386 nonstudents. In the nonstudent population, 58.5% of the male and 27.4% of the female subjects were smokers; overall, 96% smoked manufactures cigarettes. Males smoked an average of 25 cigarettes per day, and females an average of 16 cigarettes per day. Males had smoked for an average of 16 years and females an average of 13.4 years. Smoking was highest among skilled and non-skilled workers and illiterate persons. Among students, smoking was higher in males at the university (52.9%) and college (54.3%) level; 16.7% of high school males smoked. In female students at the university or college level, 20.3% and 9.1% smoked, respectively. In female of high school females smoked. Manufactured cigarettes were used by 99.3% of the students. Male students smoked a mean of 15.5 cigarettes per day for an average of 6.4 years. Female students smoked a mean of 9.6 cigarettes per day for an average of 6.2 years. Based on our findings, it is apparent that a rigorous antismoking campaign is needed.
TL;DR: In this article, the history and past occurrence of large mammalian species and their populations in Jordan, while also focusing on the present status of the mammalian species, and giving the reasons for extinctions and the preventive measures that are being taken to conserve the populations remaining.
Abstract: Jordan lies at a meeting-point of three zoogeographical areas: the Palaearctic, the Afrotropical, and the Oriental—circumstances which were conducive to habitat diversity in Jordan and hence the diversity and often abundant occurrence of different floral and faunal elements.The present paper gives information about the history and past occurrence of large mammalian species and their populations in Jordan, while also focusing on the present status of the large mammalian species, and gives the reasons for extinctions and the preventive measures that are being taken to conserve the populations remaining. In addition, this study gives a future prospective outlook for habitat and mammalian conservation, and the reintroduction programme that is being implemented in Jordan.The first part of the paper sheds light on the past existence of large mammals in Jordan. The historical sequence of events starting from the Upper Palaeolithic and continuing right up to the present, and the succession of civilizations, had a negative impact on the large mammalian populations. This section gives tabulated data on the past occurrence of 26 species, supported by evidence of their past existence such as bone remains, rock drawings, engravings, mosaics, and frescos, found in various archaeological sites in Jordan.The second part of the paper deals with the present status of large mammalian populations, their distribution being reflected through maps indicating recent sightings in some outstanding cases. Among those are reintroduced species such as the Arabian Oryx and the Syrian Wild Ass, and highly threatened species such as the Nubian Ibex. This part also investigates the reasons for extinction, which mainly link the destruction of habitats with the direct deterioration of mammalian populations. Habitat destruction was chiefly due to the rapid decline of the natural pasture areas, overgrazing, urban expansions, unorganized construction plans, human impact, mismanagement of the highlands, fire, and hunting. All of these factors led to deforestation and soil erosion, resulting in a patchy, fragile ecocomplex. The decrease of rainfall assisted the severe deterioration of natural forests.The future outlook of this study includes plans to restore ecosystems and, with them, much of the overall ecocomplex. For this and other reasons it also stresses the urgent need to establish more reserves, both grazing and natural. This concluding part of the paper encourages the improvement of national parks, and urges the authorities to look seriously at the often disastrous effects of mismanagement. The importance of collaboration between Jordan and the various international agencies is emphasized, as well as the need to speed up work on the National Conservation Strategy of Jordan.
TL;DR: In this paper, three simple prediction models of hourly global radiation, namely, a normal distribution model (ND), a half-sine wave model (HW), and a polynomial model (PO), are tested using data for a period of five years of the area of Amman, Jordan.
TL;DR: In this paper, the authors reported the characterization of electric properties of oilshale deposit and the results of the dielectric constants showed that the deposit is a heterogeneous composite material containing some conducting and insulating microstructural units.
Abstract: The characterization of electric properties of oilshale deposit is reported. The scanning electron microscopy and the results of the dielectric constants show that the deposit is a heterogeneous composite material containing some conducting and insulating microstructural units. The components of the equivalent input impedance measured at microwave frequencies (8 to 12 GHz) and the impedance at low frequencies (0.5 Hz to 30 kHz) showed frequency dependence. The real and imaginary components of the permittivity determined from the impedance data obtained at low frequencies showed an exponential decrease with frequency. The observed frequency dependence of the rock permittivity is ascribed generally to a Maxwell-Wagner type of mechanism. Also it was observed that the conductivity is almost independent of the frequency below 1 kHz and increases with frequency above this range. The values obtained for the conductivity at low frequencies indicate that the rock has an intermediate electrical conduction due to some mineralized metallic complexes and carbon content.