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During a survey on Myxobolus infection of pond-cultured common carp in Syria three Myxobolus spp. were found. Myxobolus dispar infected the gill arteries, forming large elongated plasmodia in the gill filaments. The plasmodia of M. basilamellaris were located in the gill arches at the base of the filaments. Elongated filiform plasmodia of M. encephalicus were found in the blood vessels of the brain. Despite the common occurrence of the above parasites, no disease symptoms were observed in the infected fish specimens. This is the first report on myxosporean infection of fish from Syrian waters.

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Abstract  

Mössbauer measurements were performed at different temperatures in order to examine the dynamic behavior of iron in the glass system: 42.5% P2O5, 42.5% Na2O, 15% Fe2O3. Variation of the dynamic behavior was traced by substituting B2O3 for P2O5 [30 P2O5, 12.5 B2O3, 42.5 Na2O, 15 Fe2O3] and by increasing the amount of iron at the expense of Na2O [42.5 P2O3, 15 Na2O, 42.5 Fe2O3]. The Mössbauer measurements gave the values of Debye temperature ( D), mean square displacement < 2>, mean square velocity <v 2 > of oscillation, the lattice time () and the strength parameter (B) for each glass. These values were discussed with the results of DTA, density, hardness and D. C. conductivity.

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Abstract  

Water hyacinth (Eichhornia crassipes) is known to accumulate elements from rivers and a good tool for water monitoring. To test the usefulness of such an aquatic plant as a bioindicator, we have determined the levels of Na, Ca, Cr, Fe, Co, Zn, As, Rb, Zr, Sb, Cs, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, Th, and U in water hyacinth around industrial facilities and along the studied area by instrumental neutron activation analysis. The concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cd, and Pb were determined in upstream river water and effluent factories. Contamination factor, and pollution load index was calculated. The results show that higher concentrations as well as bioaccumulation factors of these elements were observed in water hyacinth samples around the industrial facilities. On the other hand a decrease in calcium concentration was observed as a result of the thermal pollution of Nile river water. The pollution load index for the studied area was estimated to be 4.2.

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Two parts of the plant Capparis aegyptia, leaves and fruits, were extracted successfully with 4 different solvents. These solvents namely n-hexane, diethyl ether, ethyl acetate and ethanol. These extracts were tested for their toxicity against eggs and adult females of the two-spotted spider mite, Tetranychus urticae Koch. Extracts of both parts of the plant, prepared from various solvents were affected the behavior, toxicity and fecundity of females under laboratory conditions. Ethyl acetate extract of leaves and fruits was the most potent extract tested against eggs and adult females of T. urticae. In contrast, ethanol extract of fruits was the least effective extract against both tested stages. The egg stage was less susceptible to most different extracts of both parts of C. aegyptia. Leaf discs treated with LC50 concentration of various extracts showed a high percentage of repellency in case of ethanol extract from leaves and fruits (86.67 and 96.42%), respectively. Treated females with LC50 concentration of different extracts showed a higher remarkable percentage of mortality as well as a reduction in the total number of eggs laid during 15 days with fruit extracts than that with leaves extract.

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Pollack Periodica
Authors:
Maher F. Al Lebban
,
Ameer A. Alraie
,
Qusay A. Jabal
,
Laith Abdul Rasool Alasadi
,
Rawa Shakir Muwashee
, and
Waseem H. Mahdi

Abstract

Progress in building construction requires more durable concrete with higher strength. Polymer and water reducer liquids can improve concrete strength and durability. This research aims to improve the mechanical properties of polymer-modified concrete by using anti-slip sand and silica fume to achieve more durable concrete against sulfate attack and higher mechanical properties. The study shows an increase in compressive strength from 25.7 MPa for reference mix to 45.5 MPa using 15% silica fume and 30% Anti-slip sand; tensile strength increased from 2.72 to 4.4 MPa. Flexural strength also increased, and durability to sulfate attack also increased. The study includes the increment of durability against freezing-thawing cycles for different mixes.

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Acta Microbiologica et Immunologica Hungarica
Authors:
Sajith Vellappally
,
Darshan Devang Divakar
,
Abdulaziz Abdullah Al Kheraif
,
Ravikumar Ramakrishnaiah
,
Amer Alqahtani
,
M. H. N. Dalati
,
Sukumaran Anil
,
Aftab Ahmed Khan
, and
P. R. Harikrishna Varma

Oral streptococci are the major group of microbes isolated from oral microflora. They represent frequent pathogens of infective endocarditis (IE), and it is assumed that in most of the cases oral streptococci are acquired via mucosa layer of oral cavity. Staphylococcus aureus is also frequently isolated from IE as it accounts for 20%–30% of all cases. Vancomycin has been the most reliable therapeutic agent against infections caused by methicillin-resistant S. aureus (MRSA). The main objective of this study was to examine the occurrence of S. aureus species in dental caries specimens. Antimicrobial susceptibility testing of S. aureus to four antibiotics namely vancomycin, linezolid, teicoplanin, and daptomycin was performed. Detection of vancomycin resistance was conducted using polymerase chain reaction. Among the tested 150 strains, 98 were MRSA and of that 54 were vancomycin sensitive and 27 were resistant. All 98 MRSA strains were positive for mecA and 36 yielded pvl, whereas 13 carried vanA and only 2 were positive for vanB. Majority of the isolates showed sensitivity toward daptomycin and linezolid. Strains of S. aureus exhibiting decreased susceptibility to different antibiotics like vancomycin, daptomycin, and linezolid severely compromise the therapeutic alternatives and require a considerable amount of time, public awareness, and integrative health-care strategies to prevent the emergence of resistance to these compounds.

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