814 research outputs found
Quantitative characteristics and chemical composition in Caspian roach (Rutilus rutilus caspicus) sperm
In this study, quantitative characteristics and chemical composition of in roach (Rutilus rutilus caspicus) sperm were investigated. Sperm traits included sperm movement duration, percentage of motile spermatozoa, sperm density, spermatocrit and sperm volume. Some seminal plasma characteristics (sodium, potassium, calcium, magnesium and chloride) were investigated. In addition, some metabolites of seminal plasma (glucose, cholesterol and protein) were measured. The Na+ and K+ ions correlated negatively with spermatozoa motility (r = -0.0518, p<.05 and r =-0.3597, p<.01) respectively. Also, there were significant positive correlations between Ca2+ and Cl- ions with spermatozoa motility (r = 0.2945, p<.05 and r= 0.1379, p<.01), respectively. Mg+2 was positively correlated with glucose and protein (r = 0.046, p<.05 and r = 0.694, p<.05), respectively. On the other hand, a significant positive relationship was found between Na+ and K+ (r = 0.548, p<.01). These parameters can be used to evaluation of sperm quality and collecting information about developing procedures for artificial fertilization of roach
Optical properties of the ZnSe nanocrystals embedded in PMMA matrix
In this paper we report linear and nonlinear optical properties of the thin films based on nanocrystals ZnSe embedded in centrosymmetric matrix PMMA, deposited by spin coating technique. Absorption and emission spectroscopy are shown respectively a blue shift and a strong band emission near the band gap of bulk material ZnSe, which is tunable with particles size. Blue shift of the absorption edge used to evaluate the average size of nanoparticles by using the E.M.A model. The size of NCs of ZnSe was estimated to 1.98 nm, compared to the exciton Bohr radius of bulk material. We established a strong quantum confinement state for the NCS ZnSe. Using Nd:YAG laser at 1064 nm in picoseconds regime, Second order susceptibilities were measured by SHG technique. The obtained value was four order of magnitude larger compared with the bulk (ZnSe) value
Development of Acid-Soil Tolerant Corn (Zea Mays L.) with High-Quality Protein
Corn is an important food crop in Indonesia. Plant expansion has been hampered by soilacidity problem and the protein content of many corn varieties was low. This research initiates development of soil-acid-tolerant corn with highquality- protein content. Research was done on 12 factorial treatments and 3 replications as blocks in RCBD. The first factor was corn populations: Toray-1(G1), Toray-2(G2), GS- 5(G3) and GS-10(G4). The second factor was fertilizations: P1(69 kg N+36 kg P2O5+15 kg K2O per ha)); P2(115 kg N+54 kg P2O5+30 kg K2O per ha); and P3(161 kg N+72 kg P2O5+45 kg K2O per ha). The observed variables consisted of several agronomic traits, including the protein content. Results indicated that the corn populations, in general, showed good agronomic traits. The differences were mostly between populations, not between fertilizations, and no interaction was observed. The yield potential ranged from 4.25 to 6.47 ton dry seeds per ha. The protein content of seed resulted from cross ranged from 9.84% to 11.30%, as compared to the parents of 9.11% and 12.62%. This research concludes that genetic factors play an important role as confirmed by heritability estimate (h2)=0.75
Linear and nonlinear optical properties of the CdSe nanocrystals embedded in PMMA matrix
CdSe nanocrystals (NCs) were prepared using a colloidal solution and dispersed in polymethylmethacrylate (PMMA) matrix. Using spin coating technique, thin films deposited on glass substrates were prepared. Their structural and optical properties were investigated by X-ray diffraction, atomic force microscopy (AFM) and UV-visible absorption, respectively. The absorption spectra of these dispersed NCs exhibit excitonic peaks resulting from the electron-hole coupling transitions. Due to a quantum confinement effect, a blue shift is deduced by comparison of such transition with respect to reported bulk band gap. Assuming a spherical like shape for these NCs, the crystallites radius (R) was estimated by applying the effective mass approximation model and was about 2.92 nm. Such a weak radius value compared to Bohr radius (RB = 5.5 nm) leads to a strong quantum confinement regime. Moreover, the influence of this confinement effect on nonlinear optical (NLO) properties was also studied. Quadratic and cubic NLO properties were investigated by second and third harmonic generation techniques (SHG and THG) with a Q-switched Nd:YAG laser working at 1064 nm fundamental wavelength. The NLO susceptibilities Χ<2>eff, Χ<3>eff were measured to be equal to 2.27.10-10(m/V) and 2.28.10-20(m2/V2), respectively
Analysis of Microwave Heating Process for Demulsification of Water-in-Crude Oil Emulsions
In this investigation, the process of microwave heating technology was evaluated to measure the effect of some important parameters such as dielectric properties (έ and ɛʺ), rate of temperature increase (dT/dt), volume rate of heat generation (Qmw), wavelength (λ) and penetration depth (Dp) during the microwave irradiation on crude oil emulsions. Two types of Malaysian crude oil mixed together at a volume ratio of 50-50% and applied for further investigations. In order to ensure the efficiency of the process, the improvement of existing techniques and the development of new technology different ratios of water and oil were utilized to prepare the emulsions of water-in-crude oil (W/O). The emulsion samples were heated under 360 watt and 540 watt for 3 to 5 minutes. The findings of the microwave heating demulsification showed that higher microwave power (540 watt) along with the radiation time (5 min) were not much effective for water separation. This is because of the over boiling of the samples. Consequently, for microwave heating demulsification the best water separation efficiency was achieved at 3 (minutes), 360 (watt). Based on the result of microwave parameter’s calculations, it was found that parameters such as; dT/dt, Qmw, έ and ɛʺ, were inversely proportional to the radiation time. However, parameters such as λ and Dp were directly proportional to the time of the radiation
Phenotypic and genotypic evaluation of fluoroquinolone resistance in clinical isolates of Staphylococcus aureus in Tehran
Background: Fluoroquinolones are broad-spectrum antibiotics widely used in the treatment of bacterial infections such as Staphylococcus aureus isolates. Resistance to these antibiotics is increasing. Material/Methods: The occurrence of mutations in the grlA and gyrA loci were evaluated in 69 fluoroquinolone-resistant S. aureus isolates from 2 teaching hospitals of Tehran University of Medical Sciences. Results: Out of the 165 S. aureus isolates, 87 (52.7) were resistant to methicillin and 69 (41.8) were resistant to fluoroquinolone. Fluoroquinolone-resistant S. atoms isolates had a mutation at codon 80 in the grlA gene and different mutational combinations in the gyrA gene. These mutational combinations included 45 isolates at codons 84 and 86,23 isolates at codons 84,86 and 106 and 1 isolate at codons 84, 86 and 90. Fluoroquinolone-resistant S. aureus isolates were clustered into 33 PFGE types. Conclusions: The findings of this study show that the fluoroquinolone-resistant S. aureus strains isolated in the teaching hospitals in Tehran had multiple mutations in the QRDRs region of both grlA and gyrA genes
No sex scandals please, we're French: French attitudes towards politicians' public and private conduct
The notion of distinct ‘public’ and ‘private’ spheres underpins much normative and practical engagement with political misconduct. What is less clear is whether citizens draw distinctions between misdemeanours in the ‘public’ and ‘private’ spheres, and whether they judge these in systematically different ways. This paper explores attitudes to political misconduct in France. French citizens are often said to be particularly relaxed about politicians’ private affairs, but there has been little empirical evidence for this proposition. Drawing on original survey data, this paper demonstrates clearly that French citizens draw a sharp distinction between politicians’ public and private transgressions, and are more tolerant of the latter
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