21 research outputs found

    Electronic Absorption Spectra of New y-Keto-dimethine Cyanine Dyes and Apocyanines

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    New asymmetrical y-keto-dimethine cyanines (2.-f) were prepared through the condensation of phenyl glycosal derivatives (l.-e) with 2-methyl pyridinium (quinolinium)- 2yl salts. Such dyes were converted into the corresponding dyes (3a-g and 4a-d) by cyclocondensation with hydrazines or hydroxylamine hydrochloride under suitable conditions. The new synthesized cyanines were identified by elemental and spectral analyses. The U\u27V-visible absorption spectra of some selected dyes were investigated in pure and mixed solvents as well as in aqueous buffer solutions. Molecular complex formation with ethanol was verified by mixed solvent studies. Electronic transitions were attributed to either locally excited or predominantly charge transfer states. The spectral shifts were discussed in relation to molecular structure and in terms of medium effects. The variation of absorbance with pR was utilized for the determination of the pK. value for aselected compound (2e). The photostability of some selected Ä‘yes (2e, 3g and 4d) was investigated

    Effect of Tadalafil on Penile Duplex parameters in Erectile Dysfunction Patients

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    Background: Tadalafil is a PDE-5 (phosphodiesterase inhibitor) inhibitor that supports endogenous nitric oxide's vasodilatory actions and aids in erection maintenance. The penile duplex has proven to be very useful for imaging superficial structures and for determining the reasons of erectile dysfunction (ED). Objectives: To assess the effect of daily oral tadalafil 5mg for 3 months on penile duplex parameters in erectile dysfunction patients. Patients and Methods: A case control study involved 30 Egyptian patients ED. Appropriate clinical history and penile duplex examination before and after treatment with daily oral tadalafil mg for 3 months were performed. Results: The mean age of the patients was 53.17 ± 7.8 years. We founded that there was significant (p < 0.001) improvement in the level of erection after treatment. The rate of erection E1 and E2 was decreased from 53.3% to 3.3%. Likewise, the rate of E3-E5 was increased from 46.7% to 96.7%. Moreover, the mean duration of erection was elongated from 24.7 ± 5.3 to become 37.4 ± 3.8 and this was statistically significant (p < 0.001). Also, the mean peak systolic volume (PSV) was significantly (p = 0.001) increased after treatment (38.4 ± 9.1 cm/s) compared with the pre-treatment levels (23.9 ± 6.1 cm/s). Unlikely, the mean end diastolic volume (EDV) was insignificantly (p = 0.340) lower in post-treatment (2.25 ± 0.5 mL) compared with pre-treatment levels (2.97 ± 0.4 mL). Likely, the mean resistant index (RI) showed insignificant difference (p = 0.965) after treatment (0.9 ± 0.02) compared with before treatment (0.9 ± 0.08). For penile artery diameter, there was significant (p = 0.009) increase in the diameter after treatment (0.9 ± 0.1 mm) compared with before treatment (0.8 ± 0.1 mm). Conclusion: Oral daily tadalafil 5mg for 3 months is considered an effective treatment for ED according to penile duplex parameters

    Dystocia in Friesian cows and its effects on postpartum reproductive performance and milk production

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    A total of 1,243 records for 585 dairy Friesian cows from 1997–2004 were used to study the factors affecting dystocia and its effects on reproductive performance and milk production. The overall incidence of dystocia was 6.9%. The percentage of dystocia decreased with increasing live body weight, age, and parity of cows (P < 0.05); however, it increased with increasing birth weight of calves (P < 0.05). The highest percentage of dystocia was detected in winter season, but the least percentage was in summer season (P < 0.05). The percentage of incidence of dystocia was significantly (P < 0.05) higher with winter feeding compared to summer ration (8.2% vs. 5.1%). The percentage of incidence of dystocia was significantly (P < 0.05) higher with twinning than single calving (15.5% vs. 6.5%), while not significantly affected by the sex of born calves. Incidence of dystocia had adverse effects on reproductive performance and milk yield. The service interval, service period, days open, and calving interval were significantly (P < 0.05) longer in cows afflicted with dystocia compared to normal cows. The conception rate was lower (P < 0.05), but the number of service per conception was higher (P < 0.05) in cows afflicted with dystocia compared to normal cows (60.5% vs. 73.0% and 3.4 vs. 2.7, respectively). Average daily milk yield was lower (P < 0.05) by 1 kg for cows with incidence of dystocia compared to normal cows

    Buckling strength of tapered bridge girders under combined shear and bending

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    This paper represents the finite element results for the local buckling of tapered plate girders subjected to combine pure bending and shear stresses. An idealized model is developed representing the loading of the tapered panel that generates uniform normal stresses due to flexure, or uniform and constant shear stresses in the case of shear. Eigen-value analysis was performed for several tapered web plate girders that have different geometric parameters. A parametric study is made to reduce the FE model size showing the effect of decreasing the tapered panel adjacent straight panels, maintaining the same result accuracy as a complete girder model. The combined buckling capacity of bending and shear is determined by applying all possible load pattern combinations, together with different interaction ratios. An analysis study is presented to investigate the effect of the tapering angle on the combined bending–shear capacity of the girder. The study also includes the effect of the flange and web slenderness on the local buckling of the girder. Considering residual stresses as part of the loading stresses, the analysis procedure is repeated for some cases, and the effect of combining of the residual stresses together with the external loads is found. Empirical approximate formulae are given to estimate the combined flexure–shear buckling resistance of the tapered girder safely

    Computational Study of Cold-Formed-Steel X-Braced Shear Walls

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    The aim of this paper was to present a verified finite element method that represents the full-scale-braced shear walls under seismic loads and to study their ductility. The models account for different types of material and geometric nonlinearities. The screws that connect the cold-formed-steel (CFS) studs, tracks, gusset plates, and braces are considered explicitly in the model. The deformation of the hold-downs under the horizontal load is considered. The finite element program ANSYS (2012) is used to model and analyze the case studies. A parametric study is performed to investigate the response modification factor (R) of the CFS-braced shear walls. The parametric study showed that the North American Specification is about 20% conservative in estimating the (R) factor

    Isolation, Identification, and In Vitro Antifungal Susceptibility Testing of Dermatophytes from Clinical Samples at Sohag University Hospital in Egypt

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    Aim: The objective of this study was to isolate, identify, and explore the in-vitro antifungal susceptibility pattern of dermatophytes isolated from clinically suspected cases of dermatophytosis (tinea infections) attending the Dermatology Outpatient Clinic. Methods: This study was conducted at Sohag University Hospital from December 2014 to December 2015. Clinical samples (e.g., skin scrapings and hair stumps) were collected under aseptic precautions. The identification of dermatophytes was performed through microscopic examination using 10% potassium hydroxide (KOH) with 40% dimethyl sulphoxide (DMSO) mounts and culture on Sabouraud dextrose agar (SDA) and on Dermasel agar base media, both supplemented with chloramphenicol and cycloheximide. All dermatophytes isolates were subjected to antifungal susceptibility testing using the agar-based disk diffusion (ABDD) method against Clotrimazole, Miconazole, Fluconazole, and Griseofulvin. Data were analyzed via SPSS 16, using Chi square and a screening test (cross-tabulation method). Results: A total of 110 patients of dermatophytosis were studied. The patients were clinically diagnosed and mycologically confirmed as having tinea capitis (49), tinea corporis (30), tinea pedis (16), tinea cruris (9), or tinea barbae (6). The dermatophytes isolates belonged to 4 species: Microsporum canis 58 (52.7%), Microsporum gypseum 23 (20.9%), Trichophyton mentagrophytes 18 (16.4%), and Microsporum audouinii 11 (10%). The most effective antifungal drugs tested were Clotrimazole, followed by Miconazole (95.5% and 84.5% of isolates were susceptible, respectively). Conclusion: Every patient with a tinea infection should be properly studied for a mycological examination and should be treated accordingly. Dermasel agar is more useful as an identification medium in the isolation of dermatophytes. The ABDD method appears to be a simple, cost-effective, and promising method for the evaluation of antifungal susceptibility of dermatophytes

    Buckling strength of axially loaded cold formed built-up I-sections with and without stiffened web

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    This paper presents a numerical procedure using finite element analysis for the calculation of axial strength of cold formed steel built-up I-sections composed of two back-to-back channels or stiffened web sigma (Σ). The material nonlinearity of the plane and curved parts of the section were considered in the model. The effects of initial local and global geometric imperfections as well as the membrane residual stresses have been taken into consideration in the FE model. The results of the nonlinear FEA were compared with the available experimental data, and with the calculated theoretical buckling capacities based on the AISI design provisions. A parametric study was performed using the developed FE model to investigate the effects of member and geometries and imperfection values on the capacity of CFS built-up I-columns. A comparison is performed between the member’s axial capacities results from the parametric study and the design capacities calculated using the AISI. The results of the parametric study state that the design specification noted in the AISI are generally conservative for long and medium length columns, but may give un-conservative estimates for some of the short columns. Keywords: Cold-formed-steel, Nonlinear parametric columns, Finite-element, Bucklin
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