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1.
An Ordovician stratigraphically admixed palynomorph assemblage that contains palynomorphs eroded from Middle through Upper Ordovician strata characterizes the Hawban Member (restricted) of the Sarah Formation in central Saudi Arabia. This distinctive assemblage, combined with detailed sedimentology, helps identify the presence of Hirnantian Gondwanan glacial sediments on the Arabian Plate. Similar Ordovician admixed assemblages have been recognized from Upper Ordovician glacial sediments elsewhere along the Gondwanan margin. Within Saudi Arabia the composition of reworked assemblages depends upon the stratigraphic succession exposed to glacial erosion. Sylvanidium? hawbanense, which is one of the acritarchs found in glacial sediments, is newly described from Arabian Upper Ordovician strata.  相似文献   

2.
Abstract

Red date palm weevil Rhynchophorus ferrugineus Oliv. is a widespread major pest of date palm in the Kingdom of Saudi Arabia. Three different forms (black and brown with and without spots on thoracic region) were investigated using PCR-based RAPD technique. Although weevils were collected from the same geographical region of Al-Hassa in Saudi Arabia, the banding profile acquired suggested that black and brown colored morphs are genetically closer compared to the brown with spots. Intra color variation remained minimum in black but brown and brown spotted morphs exhibited more genetic variation. This genetic variation may be either due to the generation of new mutants from the non-spotted or spotted weevil or they may belong to a different race.  相似文献   

3.
Uredinia and urediniospores of six Puccinia species growing on Poaceae in southwestern Saudi Arabia were morphologically compared by light and scanning electron microscopy (SEM). Puccinia cenchri, P. fragosoana and P. isiacae were recorded for the first time in Saudi Arabia. Many differences between uredinia and urediniospores of studied Puccinia species were recorded. These differences are not related to host plant but may be due to the species of Puccinia itself. Observations by SEM led to more information in distinguishing between these Puccinia species particularly the presence of paraphyses and density and length of spines.  相似文献   

4.
Dr. Saleh M. Okla 《Facies》1992,27(1):217-223
Summary Late Permian bioclastic calcarenite beds of the middle Khuff Formation were sampled for their algal constituents near the city of Unayzah, Quassim district in central Saudia Arabia. The algal flora includes two species of udoteacean algae (Succodium difficile andSuccodium sp.), the dasycladacean algaMizzia velebitana and two species of red algae (Gymnocodium bellerophontis, Permocalculus plumosus). Other algal floral remains found forming isolated single layers which have generally been named algal microfacies. These include a phylloid microfacies, an oncoid microfacies and algal stromatolites. The Khuff Formation is well-known for its accumulation of non-associated gas and particularly for its oil accumulation in eastern Saudi Arabia and the Arabian Gulf states.  相似文献   

5.
Aerial exposure of patch reef corals occurred in Tarut Bay, western Arabian Gulf, (Saudi Arabia) between December 1991 and May 1992, and coincided with extreme low spring tides (below the predicted lowest astronomical tide-LAT). Colonies of Acropora and Stylophora occurring at the highest levels on the tops of patch reef platforms were most affected by the low tides. Corals fully exposed to air suffered total mortality, whereas those not fully exposed suffered tissue damage to their upper parts. Exposure occurred during winter months when air and water temperatures are at their lowest in the gulf. Coupling of extremely low spring tides with wind-induced negative surges (below LAT) are not regular events but are not infrequent. Cold temperatures and exposure may act in concert to produce disproportionate mortalities of reef flat corals in the shallow coastal areas of eastern Saudi Arabia. It is highly unlikely that the Gulf War oil spill played any role in the observed damage to reef corals in the Gulf in 1992.  相似文献   

6.
Purpose: Children with Down’s syndrome (DS) are considered sedentary and less engaged in recommended physical activity (PA) levels. This study compared the PA levels between children with DS and healthy children in Saudi Arabia.

Methods: The study included 85 children divided into two groups. The DS group comprised 37 children with DS aged 8–12?years recruited from the Down Syndrome Charitable Association and Al-Nahda Schools for DS. The healthy group comprised 41 healthy children aged 8–12?years recruited from regular schools in the same region. PA levels were measured over 7?days using a pedometer.

Results: The healthy group was more active than the DS group (p?p?p?Conclusions: The DS group had a high body mass index and physical inactivity compared with the second group. Obesity and physical inactivity among Saudi Arabian children with and without DS are major health concerns. Therefore, concerted efforts are needed to combat childhood obesity, promote PA, improve patient quality of life, and reduce the sedentary lifestyle among Saudi children and adolescents.  相似文献   

7.
Three genera and seven species belonging to the subfamily Zigzagiceratinae (family Perisphinctidae) are described from the Lower Bathonian of France and Saudi Arabia. Intraspecific dimorphism is recognized. A revision of the genus Franchia proposed by Sturani (1967), based on the syntypes and new specimens from south‐east France, is presented. Franchia arkelli Sturani, Franchia subalpina sp. nov., Protozigzagiceras torrensi (Sturani), Protozigzagiceras tethycum sp. nov., Protozigzagiceras flexum sp. nov. and Protozigzagiceras densum sp. nov. are described from the Digne–Castellane region of south‐east France. Megazigzagiceras subarabicum, gen. et sp. nov. is described from the Dharma region of Saudi Arabia. The successive Early Bathonian species of Franchia and Protozigzagiceras herein identified in West Tethyan areas, as members of the Mediterranean–Caucasian Subrealm, formed lasting separate peramorphoclines characterized by increasing hydrodynamic coiling of the shell. In contrast, rapid proterogenesis originated and diversified the earliest Bathonian zigzagiceratin lineages, giving paedomorphic members, commonly neotenic and more scarcely progenetic. ProceritesSiemiradzkia seems to be the oldest zigzagiceratin member in the French Subalpine, Iberian and Lusitanian basins, branched off by paedomorphosis from leptosphinctins at the Bajocian–Bathonian transition. The Mediterranean–Caucasian genera Franchia, Zigzagiceras, Zigzagites and Wagnericeras branched from successive species of Protozigzagiceras, in turn, a direct derivative of Procerites. The oldest lineages of the clade Zigzagiceratinae evolved by iterative, rapid, paedomorphic changes and additional, lasting, peramorphic modifications during the Early Bathonian.  相似文献   

8.
Samples were collected from southern, central and eastern regions of Saudi Arabia using Malaise traps and sweep nets. Nine species of Tabanidae were identified, two for the first time from Saudi Arabia, Hybomitra peculiaris (Szilády) and Atylotus pulchellus (Loew).Therefore, the total number of Tabanidae in Saudi Arabia is 31 species. Remarks of the species recorded in this study were given. A key to the genera of Tabanidae occurring in the Arabian Peninsula is also provided. Available literature for Saudi Arabian Tabanidae is summarized and provided. It is concluded that the tabanid fauna of Saudi Arabia is more similar to that of the Palaearctic region than to the Afrotropical region.  相似文献   

9.
Aerobiological studies to identify Ganoderma basidiospores were conducted using Burkard Volumetric 7-Day Recording Sampler (Burkard Manufacturing Co. Ltd., England) at three separate cities in Saudi Arabia. At one site, Jizan, close to the coast of Red Sea, up to 17% of all basidiospores counted were identified as Ganoderma spp. while less than 1% Ganoderma spp. were identified at the two non-coastal sites. A clear seasonal pattern from late autumn to early summer (October-March) with a peak in December was recorded at Jizan and the maximum concentration of Ganoderma basidiospores reached 1.9×103?m?3 in December followed by 1.2×103?m?3 in January. The diurnal pattern of Ganoderma spore concentrations, when averaged over the year had late-evening maxima (a nocturnal pattern). However, other sites that showed low concentrations of Ganoderma basidiospores did not exhibit any peak or a high maximal level. The study demonstrates that even in a desert environment, airborne activities of Ganoderma basidiospores can be recorded. The impact of Ganoderma on asthmatic patients, particularly in such environments, needs to be investigated.  相似文献   

10.
Thirty-four genera and 80 species in addition to one variety of A. nidulans were identified from 40 soil samples colleted from different places in desert of Saudi Arabia. More than forty-two species are new records from Saudi Arabian soils. Aspergillus and Penicillium contributed the greatest number of species (15 species + 1 variety and 13 species respectively).The most frequent genera were Aspergillus, Penicillium, Botryotrichum, and Ulocladium followed by Macrophomina, Rhizopus, Fusarium, Alternaria and Cladosporium from which A. fumigatus, A. terreus, A. niger, A. flavus, P. citrinum, P. corylophilum, B. atrogriseum, U. botrytis, M. phaseoli, R. stolnifer, F. moniliforme, A. alternata and C. herbarum were the most common.Comparison between the present results and those of the other studies showed that there is no fungal flora characteristic of desert soils of Saudi Arabia.  相似文献   

11.
BackgroundThe patients who require transfusion are prevalent in the Jazan Province, Saudi Arabia. Therefore, it is essential to know the frequency of blood group antigens in such a population. The Kidd blood group system (JK) has two antithetical antigens, Jka and Jkb. Antibodies to these antigens may result in delayed hemolytic transfusion reactions. The present study investigated the frequencies of Jka and Jkb and the phenotypes among Saudi blood donors living in the Jazan Province.MethodsOne hundred and forty-three samples from anonymous Saudi volunteer blood donors in the Jazan Province were serotype to detect Jka and Jkb using gel card technology and determine the phenotypes of the JK blood group system.ResultsThe prevalence of Jka and Jkb antigens were 90.64% (n = 126) and 69.40% (n = 93), respectively. The JK phenotypes were 34.96% Jk(a + b ? ) (n = 51), 12.59% Jk(a ? b + ) (n = 18), 52.45% Jk(a + b + ) (n = 75), and 0% Jk(a ? b ? ). The frequencies of the JK phenotypes in the Jazan population were significantly different from those in the Asian population (P < 0.05).ConclusionsWe reported the frequencies of the Jka and Jkb antigens and the distribution of the JK phenotypes in a group of Saudi blood donors in the Jazan Province, Saudi Arabia. The phenotype Jk(a + b + ) was the most common among the study population. Furthermore, this study emphasizes the significance of identifying the frequency of JK antigens and phenotypes in the provinces of Saudi Arabia.  相似文献   

12.
Abstract

In this study, human exposure and risks of metals through fish ingestion were predicted. Concentrations of 10 metals (Cd, As, Cr, Cu, Hg, Mn, Ni, Pb, V, and Zn) in 17 commonly eaten fish species in Saudi Arabia were characterized. Using the fish ingestion patterns, chronic daily intakes of metals among the Saudi and expatriate populations were predicted to be in the ranges of 8.89?×?10?06–1.08?×?10?02 and 6.59?×?10?06–7.97?×?10?03?mg/kg/day, respectively. The average cancer risks from inorganic arsenic were 2.76?×?10?05 and 2.09?×?10?05 for Saudi and expatriate, and the ranges were 1.61?×?10?09–1.58?×?10?03 and 2.64?×?10?09–1.27?×?10?03, respectively. The predicted risks were much lower than the previously reported risks. There were 47.4% and 42.4% chances that cancer risks would be higher than 1.0?×?10?05 (10 per million) among Saudi and expatriate, respectively. The average cumulative hazard index (HI) for Saudi and expatriate were 0.324 and 0.239 with the ranges of 0.0142–7.26 and 0.017–6.43, respectively. Approximately 3.06% and 1.56% cases among Saudi and expatriate had HI greater than unity, indicating possible health concern, respectively. Through comprehensive understanding of exposure and risks, strategies can be adopted to protect human health.  相似文献   

13.
《Mammalian Biology》2014,79(6):409-413
This work represents the most extensive genetic study of the grey wolf (Canis lupus Linnaeus, 1758) in Arabia and the first considering genetic data from multiple locations within Saudi Arabia. Previous suggestion of the occurrence of two subspecies of wolves in Arabia is not supported by this study. The genetic evidence suggests that the wolves of Saudi Arabia are genetically variable and more closely related to the Eurasian wolf Canis lupus group (dog included) than to the Indian wolf C. l. pallipes. The genetic diversity observed for C. lupus in Saudi Arabia indicates that the subspecific status C. l. arabs should be retained for the Arabian wolf. What remains unclear is the degree to which genetic introgression from domestic dogs has influenced the composition and integrity of C. lupus in Saudi Arabia.  相似文献   

14.
Electrophoresis for SDS-proteins and isoenzymes was applied to investigate the genetic variability within the tropical grasshopper Poecilocerus bufonius, which inhabits Saudi Arabia. Samples were selected from different localities that are encompassing the Sarawat Mountains in the west and An-Nafud desert in the north and middle. A range of 2 to 14 protein bands were recorded in the studied samples as measured by SDS-polyacrylamide gel electrophoresis, from which only two were common. The maximum number of protein bands has been recorded in the samples from the west and the minimum number has been recorded in the samples from the north and middle. Six arbitrary chosen enzymes were examined by native-polyacrylamide gel electrophoresis. They were peroxidase (Px), aldehyde oxidase (Ao), acid phosphatase (Acph), alcohol dehydrogenase (Adh), á and â ePsterase (Est). Fourteen presumptive gene loci and 26 polymorphic alleles have been recorded with the highest number of alleles in Taif and minimum number of alleles in Qassim. Adh, Px and Acph have not been recorded in samples from the localities of An-Nafud desert. The samples from Taif (Sarawat Mountains) were more genetically variable than the samples from other localities. Most of alleles were monomeric but only the Px-1 showed trimeric alleles in samples from Taif.  相似文献   

15.
Turaif area located in the Northern border region of Saudi Arabia is one of the most important regions of the Kingdom. This work was proposed to throw light on the diversity of lizard fauna investigated through the collection and subsequent identification of specimens from different localities of Turaif region of Kingdom of Saudi Arabia. Sixteen species of lizards belonging to 5 families (Agamidae, Gekkonidae, Lacertidae, Scincidae and Varanidae) were recorded. Lacertidae was the most common family. Three species of lizards namely Acanthodactylus orientalis, Acanthodactylus scutellatus and Acanthodactylus grandis were reported for the first time in the Turaif region of Saudi Arabia. The geographical distribution of the collected species within this province was mapped.  相似文献   

16.
Lappet-faced Vultures Torgos tracheliotus utilizing a 2200-km2, fenced, protected area in western Saudi Arabia were studied over 4 years. Numbers fluctuated seasonally from minima of c. 30 individuals in the spring to maxima of 160 birds in the autumn. All birds foraged predominantly on domestic livestock carrion outside the Reserve. In each year, up to 17 pairs attempted to breed, with 81% of pairs laying eggs, typically in large Maerua crassifolia trees. In all, 81% of the eggs hatched and 85% of nestlings fledged. Most eggs were laid in December, when mean daily air temperatures were lowest, and young usually fledged c. 180 days later. Overall, 56% of nesting attempts fledged young. Juvenile mortality over the first 3 months after fledging was at least 17%. The numbers and proportion of breeders appeared to be stable, but it is not known whether the establishment of the Reserve concentrated the nesting and roosting of vultures in the area or has attracted birds from elsewhere. Breeding success was higher than in most well-studied African populations and probably those nesting elsewhere in Arabia. Four pairs reared 52% of the fledglings observed in the Reserve over 4 years. The Saudi Arabian Lappet-faced Vultures probably belong to the subspecies negevensis and, because of the extinction of this subspecies in the wild in Israel, the well-being of the Saudi Arabian population is critical to the subspecies' conservation.  相似文献   

17.
Attention deficit hyperactivity disorder (ADHD) is one of the most common childhood behavioral disorders characterized by inattention, hyperactivity and impulsivity. In Saudi Arabia the prevalence of combined ADHD is 16.4?%. ADHD etiology is not clear and not completely understood. There are several evidences for involvement of dopaminergic, serotonergic and noradrenergic neurotransmitter systems in the pathogenesis of ADHD. Monoamine Oxidase A (MAOA) is involved in the degradation of all three of these neurotransmitters. Dopamine Transporter 1 (DAT1) plays an important role in controlling blood levels of dopamine. The aim of the present study is to investigate the association between ADHD and polymorphisms of MAOA 30?bp-promoter VNTR and DAT1 40?bp 3′ UTRVNTR in Saudi population. PCR technique was employed to detect polymorphisms of MAOA and DAT1 genes in a sample of 120 ADHD subjects and 160 controls. Alleles and genotypes frequencies for both of MAOA and DAT1 polymorphisms were compared among ADHD subjects against controls. Association between ADHD and alleles as well as genotypes for each studied polymorphisms was tested by odds ratio (OR) test and the magnitude of this association was estimated by 95?% confidence interval (95?% CI). A significant association was found between two MAOA genotypes 3/4 and 3/2 with ADHD (P?<?0.01, OR?=?3, 4.9) as a risk effect. No significant association was found with MAOA alleles. Among DAT1 polymorphisms two alleles (7 and 11 repeats) (P?<?0.01, OR?=?2.5 and 3.3) as well as two genotypes (11/11 and 11/7) (P?<?0.01, OR?=?4, 3) showed significant association with ADHD as a risk effect. On the contrary, 9 and 10 repeats revealed significant association as a protective effect as well as 10/10 and 10/9 genotypes. These findings support the hypothesis that some of the MAOA and DAT1 polymorphisms have a causative role in the development of ADHD in the Saudi population. Another polymorphism did not give rise to support this hypothesis. This is the first report investigated the association between MAOA and DAT1 polymorphism at molecular level in Saudi Arabia population as well as Arab world. Therefore further studies are needed to generalize obtained results at Saudi Arabia.  相似文献   

18.
Members of the Eurasian (or Common) Reed Warbler complex, Acrocephalus scirpaceus, are widespread across much of Europe, Africa, the Middle East and Central Asia. With its relatively complex taxonomy, the identity of several local (and sometimes remote) populations remains somewhat unresolved. In Saudi Arabia, populations of reed warblers were first identified in mangroves at Yanbu’ on the Red Sea coast in 1984, with several subsequent records up to 900 km further south toward the Yemen border. We took morphological data from 51 individuals and genetic material from three individuals captured near Jazan in southwest Saudi Arabia. Both genetic and morphometric data confirmed that these birds belong to the taxon A. scirpaceus avicenniae, sometimes referred to as the Mangrove or Red Sea Reed Warbler.  相似文献   

19.
Abdulrahman Alasmari 《Phyton》2020,89(4):1059-1081
In the Kingdom of Saudi Arabia (KSA), thousands of plants are considered to have therapeutic value. The ambiguous use of identification mainly morphological characteristics of many plants has resulted in the adulteration and displacement of plant products which undermine their therapeutic value and weak documentation of plant resources. The aims of this study were therefore to evaluate genetic variability and explore the phylogeographic architecture for Saudi medicinal plant samples using rbcL and matK genes as barcodes for genomic identification. The matK and rbcL sequences collected for these samples were used as key markers for examining the relationship between Saudi medicinal plant species based on genetic diversity. During our study we were successful in identifying and documenting 4 different species (Foeniculum vulgare, Nitraria retusa, Dodonaea viscosa, and Rumex nervosus) located in Saudi Arabia using DNA barcoding technique. A total number of 8 sequences were obtained with a total sequence length of 6176 bp, where it ranged from 617 bp to 878 bp with an average length of 772 bp. The total number of rbcL sequences length is 2801 bp, where it ranges from 617 bp to 807 bp with an average length of 700.2 bp. Out of the 4 plant samples used, only three samples were identified correctly on the species level with an identity percentage higher than 95% using rbcL gene. Additionally, 4 matK sequences have been retrieved belong to 4 species. The total number of matK sequences length is 3375 bp, where it ranges from 819 bp to 878 bp with an average length of 843.8 bp. Out of the 4 plant samples used, only two samples were identified correctly on the species level with an identity percentage higher than 98% using matK gene. Both rbcL and matK have been able to identify most of our collected plant samples by genus, and some by species. Using only one DNA-barcoding technique was not reliable for plant identification, where matK and rbcL must be used as a dual DNA-barcoding procedure.  相似文献   

20.
High sulfur content of crude oil leads to poor quality of oil products and many other negative consequences such as corrosion, catalyst poisoning and environmental pollution. Saudi Arabia is seeking to reduce sulfur content in diesel and gasoline to 10 ppm and to lower benzene content in gasoline to 1%. Biotechnological processes such as biodesulfurization can be considered an alternative or complement to conventional oil refining technologies. So, the objective of the present project is to isolate and identify endogenous fungal isolates capable of oil biodesulfurization. From 60 oil-contaminated soil samples collected from Saudi Arabia, 15 species belonged to 9 fungal genera were collected and identified morphologically and with ITS sequencing. Members of Aspergillus, Penicillium and Fusarium were the most prevalent in the investigated samples. Among the collected fungal species, only Stachybotrys bisbyiisolates were able to utilize dibenzothiophene (DBT) as the sole sulfur source. Stachybotrys bisbyi TUSb1 could desulfurize 99% of the DBT (0.3 mM) as the sulfur source by a co-metabolism reaction with other carbon sources through the same pathway as 4S (involves sequential oxidation of the sulfur part and cleaving of the C–S bonds), and produced 2-hydroxy biphenyl (2-HBP) during 7 days of incubation at 30°C and 180 rpm. Stachybotrys bisbyi TUSb1 showed broad specificity for removing sulfur in different sulfur-containing compounds.  相似文献   

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