Effects of endurance training on the serum level of sex hormones and sperm parameters after diabetic induction by streptozotocin-nicotinamide

Background and aims: The aim of the present study was to investigate the effects of endurance training on the serum levels of sex hormones and sperm parameters in the induced diabetic rats by Streptozotocin-Nicotinamide. Methods: In this experimental study, 36 male Wistar rats in the weight range of 200±48 g, assigned randomly in three groups: Healthy control, diabetic control and diabetic edurance training. For diabetic induction, intraperitoneal injection of nicotinamide solution (120 mg/kg) and Streptozotocin (STZ) solution (65 mg/kg) method was used after 12 hours of food starvation. One week after injection of STZ, nicotinamide solution, the endurance training protocol was performed for ten weeks and 24 hours after the last training session, left epididymis of the rats was collected for studying sperm parameters and blood serum samples to evaluate sex hormones. Data were analyzed using one-way ANOVA and Turkey’s Post Hoc test at the level of P<0.05. Results: Ten weeks of resistance training caused a significant decrease in blood glucose in the endurance training group in comparison to the diabetic group (P=0.013). Also, endurance training in the endurance training group led to a significant increase in the serum levels of testosterone (P=0.000) LH (P=0.002) and FSH (P=0.029 in comparison to the diabetic control group. In addition, it was not observed no significant difference in the endurance training group compared to the health control group in the sperm parameters such as sperm count (P=0.065), and normal morphology (P=0.067). Conclusion: It seems endurance training can improve sperm parameters, including sperm count and normal morphology through increasing the serum level of testosterone hormones, LH and FSH in rats with Type 2 diabetes mellitus

Study of optical absorbance in porous silicon nanowires for solar cell applications

International audiencePorous silicon nanowires (PSiNWs) layers fabrication was reported. Reflectance spectra were measured as a function of the nanowire length and were inferior to 0.1% and a strong photoluminescence (PL) signal was measured from samples. Models based on cone shape of nanowires located in circular and rectangular bases were used to calculate the reflectance using the Transfert Matrix Formalism (TMF) of PSiNWs layer. The modeling of the reflectance permits to explain this value by taking account into the shape of the nanowires and its porosity. Optical absorbance and transmission were also theoretically studied. The absorbance was superior to that obtained with silicon nanowires and the ultimate efficiency was about equal to 25% for normal incidence angle. These results could be applied to the potential application in low-cost and high efficiency PSiNWs based solar cells

Propriétés optiques et physiques des couches de nanofils de silicium poreux pour des applications photovoltaïques

National audienceDes nanofils verticaux en silicium poreux présentant une forte densité ont été élaborés sur substrat de silicium en utilisant un procédé électrochimique de gravure. Ces couches ont été observées par MEB et MET ce qui a permis d'en déduire que les nanofils de silicium poreux ont une forme conique. La réflectance de ces couches a été mesurée et est inférieure à 0.1% pour des épaisseurs supérieures à 10 µm. La réflectance de ces couches a été modélisée en utilisant le formalisme des matrices de transfert associé au modèle de Bruggeman et en considérant la forme conique observée de ces nanofils. Les résultats théoriques sont discutés et confirment ceux expérimentaux. La remarquable diminution de la réflectivité des ces couches montrent que les couches de nanofils en silicium poreux ont une forte potentialité comme couche antireflet pouvant être utilisée dans le domaine des cellules solaires

A new ductile moment-resisting connection for precast concrete frames in seismic regions: An experimental investigation

A new ductile moment-resisting beam–column connection is developed for precast reinforced concrete (RC) frames in high seismic zones. The proposed connection provides good structural integrity in the connections and can reduce construction time by eliminating the need for formworks and welding, and minimizing cast-in-place concrete volume. A series of cyclic loading tests were carried out on six full-scale interior and exterior precast connections and two monolithic connections, all designed for use in high seismic zones. Test variables included the type of stirrups (open and closed) and the stirrup spacing in the beam connection zone. Test specimens were subjected to a constant axial load and a reverse cyclic loading based on a given displacement history. Flexural strength, ductility, strength degradation and energy dissipation capacity of the precast and monolithic connections are compared. The proposed interior and exterior moment-resisting connections proved to be efficient at improving the seismic performance of precast concrete frames in high seismic zones. While the precast connections provided adequate flexural strength, strength degradation and drift capacity, they exhibited considerably higher ductility and energy dissipation compared to similar monolithic specimens

Ultra-low reflection porous silicon nanowires for solar cell applications

International audienceHigh density vertically aligned Porous Silicon NanoWires (PSiNWs) were fabricated on silicon substrate using metal assisted chemical etching process. A linear dependency of nanowire length to the etching time was obtained and the change in the growth rate of PSiNWs by increasing etching durations was shown. A typical 2D bright-field TEM image used for volume reconstruction of the sample shows the pores size varying from 10 to 50 nm. Furthermore, reflectivity measurements show that the 35% reflectivity of the starting silicon wafer drops to 0.1%, recorded for more than 10 µm long PSiNWs. Models based on cone shape of nanowires located in a circular and rectangular bases were used to calculate the reflectance employing the Transfert Matrix Formalism (TMF) of the PSiNWs layer. Using TMF, the Bruggeman model was used to calculate the refractive index of PSiNWs layer. The calculated reflectance using circular cone shape fits better the measured reflectance for PSiNWs. The remarkable decrease in optical reflectivity indicates that PSiNWs is a good antireflective layer and have a great potential to be utilized in radial or coaxial p-n heterojunction solar cells that could provide orthogonal photon absorption and enhanced carrier collection

Shape optimization of cold-formed steel beam-columns with practical and manufacturing constraints

Peer reviewedPostprin

Clarifying of Quality of Care in Abdominal and Pelvic Trauma Based on the Nursing Managers' Perspective

Introduction: Abdominal trauma is one major causes of mortality and its prevalence is increasing. Despite the researches conducted in quality of care, review of literature show that no study has done about the quality of care in abdominal and pelvic trauma. This study aimed to clarify the quality of care in abdominal and pelvic trauma based on the nurse managers' perspective. Method: In this descriptive qualitative study, 14 nurse managers employed in emergency department of one of the health centers in Rasht City, Iran, were selected purposefully. Semi-structured interviews were used to collect the data. Sampling continued until data saturation. Data were analyzed using qualitative content analysis via MAXQDA 2007 software. Results: Data analysis led to extraction of 321 primary codes, 8 subcategories, 3 categories, and 1 main theme. The main theme named "convergence of comprehensive health care services" consists of three categories entitled “life-saving care", "essential care", and "foundations of service quality". Conclusion: Despite the implementation of specific aspects of abdominal and pelvic trauma care as "lifesaver care", there are significant deficiencies in relation to certain aspects of "essential care", especially in communication with patients require necessary actions, which should be modified or eliminated by the relevant authorities. Keywords: Quality of care, Nursing care, Abdominal injuries, Trauma, Nurse manager

Constrained optimization of anti-symmetric cold-formed steel beam-column sections

CRediT authorship contribution statement Hossein Parastesh: Methodology, Supervision, Resources. Seyed Mohammad Mojtabaei: Conceptualization, Methodology, Software, Formal analysis, Investigation, Visualization, Writing - original draft. Hamed Taji: Conceptualization, Methodology, Software, Formal analysis, Investigation. Iman Hajirasouliha: Conceptualization, Validation, Writing - review & editing, Supervision. Alireza Bagheri Sabbagh: Methodology, Validation, Supervision.Peer reviewedPostprin