245 research outputs found

    Floristic Composition, Life Form and Chorology of Plant Life at Al-Saoda, Asir Region, South-Western Saudi Arabia

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    Asir highlands constitute a major part of south-western Saudi Arabia, and have a temperate climate at elevations above 2500 m a.s.l. This area has a complicated topography. The variations in elevation and topography have resulted in distinctive vegetational zones.  Floristic composition, life form and chorology of plant life at Al-Saoda region south – western Saudi Arabia was studied. Three  major  wadis (sites) were investigated , every site was represented by three localities representing up-stream , mid-stream and down-stream portions of each site. Nine field trips were carried out during 18 months  .Vegetation of  three localities ( Wadi Tahlal , Wadi Al-Moght  and Beni Mazen ) was studied .  Results revealed that the region considers a hot-spot in the Kingdom in term of plant diversity and more diverse compared with other well studied regions in Saudi Arabia. A total of 103 plant species belonging to 40  families were recorded in study area. The major plant families that contributed in the formation of vegetation of the area in question were Asteraceae ( 22.3%) followed by Papilionaceae( 8.7%) ,poaceae,  ( 6.7%), Lamiaceae  ( 5%), Mimosoaceae ( 4%) while other families each was represented by two or one species. Therophytes exhibited the maximum number of species (35%), followed by chaemophytes (32%), hemicryptophytes (15%) and phanerophytes (9.8%), while the least frequent life form class was geophytes and epiphytes .Chorological characteristic of the recorded flora showed that Saharo-Arabian and Sudanian elements constitute % of  the total flora. Keywords: dsfloristic composition , vegetation , Asir region ,chorology , diversit

    Fish Classification Using Deep Learning

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    Abstract: Fish are important for both nutritional and economic reasons. They are a good source of protein, vitamins, and minerals and play a significant role in human diets, especially in coastal and island communities. In addition, fishing and fish farming are major industries that provide employment and income for millions of people worldwide. Moreover, fish play a critical role in marine ecosystems, serving as prey for larger predators and helping to maintain the balance of aquatic food chains. Overall, fish play a vital role in supporting human well-being and the health of our planet. . Fishes have a lots of types such that: Red Mullet, Sea Bass, Striped Red Mullet and Shrimp. Each of them has its own shape and characteristics that differ from other types. We proposed a system that recognize nine types of fishes using deep learning. We trained the model with a dataset that contain 9000 images that were slit into 6300 images for training, 1350 for validation and 1350 for testing. The proposed model achieved accuracy (99.68%), precision (99.69%), recall (99.68%), and f1-score (99.68%). This indicates that our proposed model can effectively predicate and classify different types of fish with very high accuracy

    Synthesis and biological assessment of new benzothiazolopyridine and benzothiazolyl- triazole derivatives as antioxidant and antibacterial agents

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    ABSTRACT. A novel series of benzothiazolopyridine derivatives was synthesized via interaction of -2-(benzothiazol-2-yl)-3-(4-chlorophenyl)acrylonitrile (2) with a diverse of commercially available reagents (indandione, thiobarbituric acid, and malononitrile). Moreover, a novel group of benzothiazole linked substituted 1,2,3-triazole derivatives were synthesized by exploring the chemical behavior of 5-benzothiazolyl-2-(4-chlorophenyl)-triazol-4-amine through refluxing in glacial acetic acid, condensation with phthalic anhydride, and cyanoacetylation reactions. All newly synthetized compounds have been tested for their antioxidant and antibacterial activities compared with ascorbic acid and Ampicillin as reference drugs, respectively. The benzothiazolo- pyridopyrimidine compound 6 was found the most potent antioxidant agent with IC50 = 0.015 mg/mL compared to the results of ascorbic acid (IC50 = 0.022 mg/mL). The investigated compounds showed no antibacterial properties against Gram-negative bacterial species, Pseudomonas aeruginosa and Escherichia coli. Benzothiazolopyridine derivative 5 displayed the best growth inhibition against Gram-positive bacteria, Staphylococcus aureus and Bacillus cereus with inhibition zones 24 and 20 mm, respectively.   KEY WORDS: Benzothiazole, Pyridobenzothiazole, 1,2,3-Triazole, Naphtharidine, Antioxidant   Bull. Chem. Soc. Ethiop. 2022, 36(2), 451-463.                                                              DOI: https://dx.doi.org/10.4314/bcse.v36i2.17                                                     &nbsp

    Investigating neutron-proton pairing in sd -shell nuclei via (p, He 3) and (He 3,p) transfer reactions

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    Neutron-proton pairing correlations are investigated in detail via np transfer reactions in N = Z sd-shell nuclei. In particular, we study the cross-section ratio of the lowest 0+ and 1+ states as an observable to quantify the interplay between T = 0 (isoscalar) and T = 1 (isovector) pairing strengths. The experimental results are compared to second-order distorted-wave Born approximation calculations with proton-neutron amplitudes obtained in the shell-model formalism using the universal sd-shell interaction B. Our results suggest underestimation of the nonneglible isoscalar pairing strength in the shell-model descriptions at the expense of the isovector channel.Séptimo Programa Marco de la Comisión Europea-FP7/2007-2013 00376National Science Foundation (NSF) de los Estados Unidos-PHY-1404442US Department of Energy, Office of Science, Office of Nuclear Physics-DE-AC02-05CH1123

    Search for {\eta}'(958)-nucleus bound states by (p,d) reaction at GSI and FAIR

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    The mass of the {\eta}' meson is theoretically expected to be reduced at finite density, which indicates the existence of {\eta}'-nucleus bound states. To investigate these states, we perform missing-mass spectroscopy for the (p, d) reaction near the {\eta}' production threshold. The overview of the experimental situation is given and the current status is discussed.Comment: 6 pages, 3 figures; talk at II Symposium on applied nuclear physics and innovative technologies, September 24th - 27th, 2014, Jagiellonian University, Krak\'ow Poland; to appear in Acta Physica Polonica

    Spectroscopy of η\eta'-nucleus bound states at GSI and FAIR --- very preliminary results and future prospects ---

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    The possible existence of \eta'-nucleus bound states has been put forward through theoretical and experimental studies. It is strongly related to the \eta' mass at finite density, which is expected to be reduced because of the interplay between the UA(1)U_A(1) anomaly and partial restoration of chiral symmetry. The investigation of the C(p,d) reaction at GSI and FAIR, as well as an overview of the experimental program at GSI and future plans at FAIR are discussed.Comment: 7 pages, 3 figures; talk at the International Conference on Exotic Atoms and Related Topics (EXA2014), Vienna, Austria, 15-19 September 2014. in Hyperfine Interactions (2015

    Microscopic View on Short-Range Wetting at the Free Surface of the Binary Metallic Liquid Gallium-Bismuth: An X-ray Reflectivity and Square Gradient Theory Study

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    We present an x-ray reflectivity study of wetting at the free surface of the binary liquid metal gallium-bismuth (Ga-Bi) in the region where the bulk phase separates into Bi-rich and Ga-rich liquid phases. The measurements reveal the evolution of the microscopic structure of wetting films of the Bi-rich, low-surface-tension phase along different paths in the bulk phase diagram. A balance between the surface potential preferring the Bi-rich phase and the gravitational potential which favors the Ga-rich phase at the surface pins the interface of the two demixed liquid metallic phases close to the free surface. This enables us to resolve it on an Angstrom level and to apply a mean-field, square gradient model extended by thermally activated capillary waves as dominant thermal fluctuations. The sole free parameter of the gradient model, i.e. the so-called influence parameter, κ\kappa, is determined from our measurements. Relying on a calculation of the liquid/liquid interfacial tension that makes it possible to distinguish between intrinsic and capillary wave contributions to the interfacial structure we estimate that fluctuations affect the observed short-range, complete wetting phenomena only marginally. A critical wetting transition that should be sensitive to thermal fluctuations seems to be absent in this binary metallic alloy.Comment: RevTex4, twocolumn, 15 pages, 10 figure
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