Baghdad Science Journal
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Embryonic Development of Eye Lens in Mosquito fish Gambusia affinis (Baird and Girard, 1853)
No full textThe embryonic development of the Mosquito fish(Gambusia affinis) eye lens was investigated using light microscopy .The results indicated that the embryonic development of the lens does not correspond to that of the non spherical lenses of terrestrial vertebrates .This study showed that a very small cavity in the lens vesicle appears during development ,but it differs from that of the mammalian lens.
The most important aspect in this study is that ,the posterior edge of the simple cuboidal epithelium which covers the anterior half of the surface of the lens is situated well beyond the equatorial region of the lens .As a result , the germinal and transitional zones became closer to the posterior pole rather than the anterior pole of the lens.
This might be an important factor in causing the lens to be spherical rather than being biconvex
Evaluation of humoral immunity in Golden Hamsters experimentally infected with Leishmania donovani
No full textThis study has evaluated the humoral immune response in Golden Hamsters experimentally infected with Leishmania donovani along (4) times of follow up (15, 30, 60, 90) days after infection. Indirect haemagglutination test was used to determine the antibody titer through the various stages of the study. Also the progress of the infection was studied depending on some of the visceral changes caused by the parasite, like weight of liver, length & weight of spleen & the count of Leishmania parasites in spleen were measured. Results has shown that there was an increase in antibody titer & the maximum value was recorded at the 4th day of follow up (90 days after infection) as well as that there was an increase in the length of the spleen, weight of liver & spleen comparing with the control animals, also the count of the parasites in the spleen was increasing gradually through the 4 times of follow up
THIAMINE – INDUCED FORMATION OF THE MONOPYRROLE MOIETY OF PRODIGIOSIN
Get PDFThiamine stimulates the production of a red pigment , which is chromatographically and spectrophotometrically identical to prodigiosin , by growing cultures of serratia marcescens mutant 9-3-3 . this mutant is blocked in the formation of 2- methyl -3- amyl pyrorol( MAP),the monopyrrole moiety of prodigiosin , but accumulates 4-methoxy-2, 2-bipyrrole -5- carboxaldehyde (MBC) and can couple this compound with( MAP) to form prodigiosin .
Addition of thiamine caused production of( MAP) , and as little as 0.02 mg of thiamine / ml in peptone- glycerol medium stimulated production of measurable amounts of prodigiosin. Phosphate saltes and another type of peptone decreased the thiamine- induced formation of prodigiosin ,yeast extract and glycerol enhanced formation of this substance.
Thiamine also enhanced production of prodigiosin by wiled – type Strain Nima of S. marcescens .
The pyrimidine moiety of thiamine was also 10% as effective as the vitamin ; the thiazol moiety only 4% , and the two moieties together , 25% .
Thiamine did not stimulate production of prodigiosin biosynthesis as strain 9-3-3 .
This is not surprising since strain 9-3-3 originated as a result of two mutational events one event may involve thiamine directly , and the other may involve the biosynthesis of( MAP)
Synthesis of Novel N-Substituted Dimethylmaleimidyl Esters and Their Applications as Plasticizers for Poly(Vinyl Chloride)
Get PDFThree N-(hydroxylphenyl) dimethylmaleimides were directly prepared in good yields (81-86)% from the reaction of dimethylmaleic anhydride with amino phenols.
The prepared imides were esterified to the corresponding benzoates, methacrylates and cinnamates via their reaction with different acid chlorides in the presence of triethylamine.
The prepared esters were tested as plasticizers for PVC via preparing of thirty six samples of PVC with the prepared esters in certain weight ratio followed by recording their softening points. Comparison the results with the universal plasticizers for PVC (DOP) and (DBP) indicated that the prepared esters in general have high plasticizing efficiency
Bilinear System Identification Using Subspace Method
Get PDFIn this paper, a subspace identification method for bilinear systems is used . Wherein a " three-block " and " four-block " subspace algorithms are used. In this algorithms the input signal to the system does not have to be white . Simulation of these algorithms shows that the " four-block " gives fast convergence and the dimensions of the matrices involved are significantly smaller so that the computational complexity is lower as a comparison with " three-block " algorithm
Study the effect of thickness and annealing temperature on the Electrical Properties of CdTe thin Films
Get PDFThe electrical properties of polycrystalline cadmium telluride thin films of different thickness (200,300,400)nm deposited by thermal evaporation onto glass substrates at room temperature and treated at different annealing temperature (373, 423, 473) K are reported. Conductivity measurements have been showed that the conductivity increases from 5.69X10-5 to 0.0011, 0.0001 (?.cm)-1 when the film thickness and annealing temperature increase respectively. This increasing in ?d.c due to increasing the carrier concentration which result from the excess free Te in these films
A Fixed Point Theorem for L-Contraction in Generalized D-Metric Spaces
Get PDFWe define L-contraction mapping in the setting of D-metric spaces analogous to L-contraction mappings [1] in complete metric spaces. Also, give a definition for general D- matric spaces.And then prove the existence of fixed point for more general class of mappings in generalized D-metric spaces
Effect the combination of antibiotics on clinical isolates of Staphylococcus aureus
No full textAtotal of 75 different clinical samples were collected from different hospitals in Baghdad Biochemical and morphological characterization tests showed that forty isolates were identified as Staphylococcus aureus Antibiotic susceptibility tests of all isolates towards ten antibiotics were carried out and results showed that many isolates (97.5 %) were resistant to ?-lactam antibiotic , 70 % were resistant to Tetracyclinee , 62.5% were resistant to co-trimoxazole , 60 % were resistant to ciprofloxacin , 55% were resistant both of chloramphenicol and erythromycin , 52.5% were resistant to gentamicin , 35% were resistant to rifampicin , 10% were resistant to vancomycin . According to the above results the S.aureus I1 which is isolated from patients with osteomyelitis showed resistant to all ten antibiotics therefore was used in the followed experiments. The minimum inhibitory concentration (MIC) of S.aureus I1 vancomycin, cefotaxim , penicillin G, amoxicillin , ciprofloxacin , co-trimoxazole ,gentamicin, rifampicin was checked.The results showed that isolates had MIC between (390-12500) ?g/ml. The combination of different antibiotics with vancomycin showed synergistic effect based on the Fractional inhibitory concentration index (FIC)
Best estimation for the Reliability of 2-parameter Weibull Distribution
No full textThis Research Tries To Investigate The Problem Of Estimating The Reliability Of Two Parameter Weibull Distribution,By Using Maximum Likelihood Method, And White Method. The Comparison Is done Through Simulation Process Depending On Three Choices Of Models (?=0.8 , ß=0.9) , (?=1.2 , ß=1.5) and (?=2.5 , ß=2).
And Sample Size n=10 , 70, 150 We Use the Statistical Criterion Based On the Mean Square Error (MSE) For Comparison Amongst The Methods
Synthesis and Characterization of (Fe(II),Co(II),Ni(II) and Cu(II)) Complexes with Schiff Base derived from [benzoyl hydrazine] with [benzyl mono oxime]
No full textThe reaction of [Benzoyl hydrazine] with [Diphenyl mono oxime] and Glacial acetic acid was carried out in methanol gave a new tridentate ligand [Benzoic acid (2-hydroxyimino- 1, 2-diphyneylethylidene) - hydrazide]. This ligand was reacted with some metal ions (Fe(II), Co(II), Ni(II), and Cu(II)) in methanol with (1:1) metal : ligand ratio to give a series of new complexes of the general formula [M(L)Cl2.H2O], where M= Fe(11), Co(11), Ni(11) and Cu(11).
All compounds were characterized by spectroscopic methods (I.R, UV-Vis), elemental microanalysis (C.H.N), atomic absorption, magnetic susceptibility, and conductivity measurements. From the obtained data the proposed molecular structures were suggested for the complexes of Fe (II), Co (II), Ni (II) and Cu (II) are of geometric octahedral