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A reduced-order modeling (partitioned reduced-order modeling [P-ROM]) method for structural systems is presented, which employs recently developed displacement-only partitioned (DP) equations of motion. It is shown that the DP equations directly yield the same eigenvalues as the assembled equations of finite element model, and the corresponding eigenvectors are a partitioned form of the assembled eigenvectors. A unique feature of the proposed P-ROM method is its a priori mode selection criterion that can be utilized with the desired target accuracy assigned by the modeler. Thus, the proposed P-ROM method bypasses the arduous task of substructural mode synthesis (viz., selecting modes for each substructure) and directly constructs the ROM equations. An attractive feature of the proposed P-ROM method is that it can handle nonmatching mesh problems with ease. The performance of the present P-ROM method is illustrated through several numerical ROM examples and the ensuing transient analysis. [ABSTRACT FROM AUTHOR]

Recently, multiband metamaterial absorbers have gained considerable attention from research and development communities due to their applications in filtering, stealth, and sensing. However, these multiband absorbers are mostly comprised of multilayered metamaterial structures that make them bulky and expensive. In this paper, we investigated a novel multiband absorber made of a single layer of the tree-shaped fractal. The proposed fractal-based metamaterial absorber (FMA) shows the polarization- and angular-sensitive features of the absorption. Furthermore, it is observed that absorptivity is attained due to electric and magnetic resonance. The proposed multiband absorber would be useful for filtering, polarization- and angle-sensing, and shielding. Furthermore, the simulation results are verified by experiments. [ABSTRACT FROM AUTHOR]

The aims of this study were (i) to determine the seminal fluid parameters, levels of serum reproductive hormones, testicular size and diameter of seminiferous tubules depending on multiple testicular biopsies from non-obstructive azoospermic (NOA) patients, and (ii) to assess the effect of smoking on concentrations of serum reproductive hormones. Thirty four NOA patients were involved in the present study. The selection of patients was based on an average of 2 pelleting seminal analysis, reproductive hormones profile and diagnostic testicular biopsy. A detailed questionnaire was used to obtain a thorough history from the patients. The results of this study showed that the mean age of NOA patients with Sertoli cell only syndrome (SCOS) was 33.875 years, and 47.05 % of NOA patients have had 2-4 years duration of infertility. Macroscopic examination of seminal fluid appeared to have normal values as reported by WHO. Non-significant (P>0.05) difference was observed for testicular size and diameter of seminiferous tubules between right and left testis. High and abnormal concentrations of serum FSH were registered for NOA patients with SCOS. However, non-significant (P>0.05) differences were reported for concentrations of serum reproductive hormones between smokers and non smokers. In conclusion, testicular biopsy is the useful and predictable diagnostic tool for NOA patients with SCOS. Further studies are needed to explain the etiology, management and prognosis of NOA patients with SCOS.

Successful oocyte fertilization and normal embryonic development of mice were considered the most important diagnostic criteria for the safety of materials and tools used for human in vitro fertilization and embryo transfer (IVF-ET). Therefore, we studied the influence of cumulus cells co-culture and protein supplement within culture medium on percentages of in vitro fertilization (IVF) and normal development of early stages of mouse embryo later. Oocytes were collected and treated with hyaluronidase to remove cumulus cells. Oocytes were divided into four groups namely: Group-1: Oocytes incubated within modified Earl’s medium (MEM) supplied with 10% inactivated bovine amniotic fluid as a protein source and cumulus cells; Group-2: Oocytes incubated with MEM supplied with cumulus cells only; Group-3: Oocytes incubated with MEM supplied with 10% inactivated bovine amniotic fluid only; and Group-4: Oocytes incubated with MEM free of both protein source and cumulus cells. For IVF, 5-6 oocytes were incubated with active spermatozoa under paraffin oil for 18-20 hours at 37° oC in 5% CO2. Percentages of IVF and embryonic development were then recorded. Best results for IVF and normal embryonic development were achieved from oocytes of Group-1 when compared to the other groups. As compared to Group-1, the percentage of IVF for Group-2 and Group-3 were decreased insignificantly and significantly (P

Objective: To evaluate the effect of honey supplemented to cryoprotectant medium on post-thaw sperm motility, concentration, morphology and agglutination. Materials and methods:Thirty semen samples were collected from 30 infertile patients. After assessment of semen analysis, semen samples were divided into 3 aliquots (0.7ml for each) and mixed with 1 ml of cryopreservation solution (G1, control) alone, or enriched with 5% honey (G2) or with 10% honey (G3) for cryopreservation. Cryopreservation was done at -196°C in liquid nitrogen and thawing was performed after six months. Direct swim up technique was used for in vitro sperm preparation post-thawing. Sperm parameters were assessed and data were statistically analyzed pre- and post-thawing. Results: Results appeared that the percentage of sperm motility for G1 and G2 groups were significantly reduced (P < 0.05) post-thawing when compared to pre-cryopreservation. However, there was no significant difference in the total motility (%) of the post-thaw sperm between the G1 and G2 groups. While there was significant increased (P < 0.05) in the percentage of normal sperm morphology for G1 and G3 groups post-thawing. Post-thawing normal sperm morphology (%) for G3 group was significantly increased (P < 0.05) as compared to G1 and G2 groups. In contrast non significant differences (P > 0.05) were observed between G1 and G2 groups. Significant reduction (P < 0.05) was seen in the sperm concentration for all groups post-thawing as compared to pre-cryopreservation groups. After thawing the results reveal significant reduction (P < 0.05) in the sperm agglutination (%) for G3 group as compared to G1 and G2 groups. Conclusion: The results of this study indicated that the supplementation of honey (10%) to cryoprotectant solution results in enhancement of sperm quality post-thawing.

sildenafil citrate (SC) is widely used for the treatment of erectile dysfunction and maintains a sufficient erection for satisfactory sexual performance. Very limited literatures were published about effects of SC on histological changes of epididymes in human or laboratory animals. The aim of this study was to investigate the influence of different concentrations of SC for different administration periods on some histological parameters of mice epididymes. Seventy five male mice (7-8) weeks old, weighing (23-25)g were used in the present study. The possible effect of SC was tested through the treatment groups of mice with different doses of SC (2, 4, 8, 16)mg/Kg body weight, and for different periods (1, 3, 5) weeks. Histological examination of epididymes were carried out and compared with those belong to untreated group. Results revealed no significant differences (P>0.05) in epididymal weight, tubules diameters and thickness of epithelial layer between treated groups and control group. Conclusion in this study, SC has no effect on epididymis histology

The objectives of the present study are to determine the effect of different concentrations of aqueous and oil extracts of cottonseed on haematological parameters. Groups of male mice were orally administered aqueous extract [20mg/kg/l day (G2) and 40 mg/kg/day (G3)] and other groups were administered oil extract [20% (G5) and 40% (G6)] for six weeks. The results showed that there was a significant (P0.05) differences were shown in RBC and WBC count among G5and G6 as compared to G4. Significant (P