14 research outputs found

    Integration of wind and tidal turbines using spar buoy floating foundations

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    Floating platforms are complex structures used in deep water and high wind speeds. However, a methodology should be defined to have a stable offshore structure and not fail dynamically in severe environmental conditions. This paper aims to provide a method for estimating failure load or ultimate load on the anchors of floating systems in integrating wind and tidal turbines in New Zealand. Using either wind or tidal turbines in areas with harsh water currents is not cost-effective. Also, tidal energy, as a predictable source of energy, can be an alternative for wind energy when cut-in speed is not enough to generate wind power. The most expensive component after the turbine is the foundation. Using the same foundation for wind and tidal turbines may reduce the cost of electricity. Different environment scenarios as load cases have been set up to test the proposed system's performance, capacity and efficiency. Available tidal records from the national institute of Water and Atmospheric Research (NIWA) have been used to find the region suitable for offshore energy generation and to conduct simulation model runs. Based on the scenarios, Terawhiti in Cook Strait with 110 m water height was found as the optimized site. It can be seen that the proposed floating hybrid system is stable in the presence of severe environmental conditions of wind and wave loadings in Cook Strait and gives a procedure for sizing suction caisson anchors

    L'accouchement des grossesses gémellaires et pronostic materno-fœtal dans un Centre Universitaire Tunisien de niveau 3: étude rétrospective à propos de 399 cas

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    En dépit des progrès obstétricaux et pédiatriques, les grossesses gémellaires représentent une situation à haut risque aussi bien pour le déroulement de la grossesse que pour l´accouchement et reste encore une situation angoissante pour l´équipe obstétricale. Le but de cette étude était de décrire la pratique des accouchements des grossesses gémellaires au service de gynécologie obstétrique de Sousse, de décrire le pronostic maternel et fœtal et d´analyser les facteurs pouvant l´influencer. Nous avons réalisé une étude descriptive, rétrospective portant sur les accouchements des grossesses gémellaires sur une période de deux ans. Ont été incluses dans l´étude les grossesses gémellaires ayant atteint au moins 28 semaines d´aménorrhée (SA) et les femmes ayants une grossesse gémellaire compliquée d'une mort fœtale in utéro. Ont été exclues les femmes ayant une grossesse gémellaire et accouchés avant 28 SA. Les grossesses bi-choriales bi-amniotiques représentaient 67% des cas, contre seulement 11,5% de grossesses mono-choriales bi-amniotiques et 3% de grossesses mono-choriale mono-amniotique. Nous avons recensés 52 césariennes programmées. Le travail a été spontané dans 304 cas. Il a été déclenché dans 43 cas. Au total 178 parturientes ont accouché par voie basse (44,6%), contre 215 par voie haute (53,9%). Le taux de césarienne pour le deuxième jumeau était de 1,5%. Quand l'accouchement était par voie basse, 19 cas de complications ont été observés (10,7%). Nous avons analysé le score d'Apgar du premier jumeau et du deuxième jumeau en fonction du mode d'accouchement. Il n'y a pas eu de différence statistiquement significative du score d'Apgar entre les deux voies d'accouchement. La morbi-mortalité périnatale est plus importante pour le deuxième jumeau que pour le premier jumeau. La morbidité maternelle en cas d´accouchement par voie basse était supérieur à la morbidité en cas d´accouchement par césarienne. Il n´y a pas de différences significatives dans le score d´Apgar selon que les enfants sont nés par voie basse ou par césarienne

    Fertility Preservation :A Big Dilemma For Patients With Breast Cancer

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    Introduction : Breast cancer is one of the most common malignancies in women. Cytotoxic chemotherapy or drugs exert a negative effect on fertility potential. Techniques,such as ovarian suppression, oocyte and embryo freezing, InVitro Maturation, and ovarian tissue freezing, are necessary to preserve fertility. Methods: To conduct this study, a query was conducted on Persian and English sources databases as Scoupus, Google Scholar, Pub Med, and Science Direct during the last 24 years using the following keywords: breast cancer, infertility, fertility preservation, oocyte freezing, and embryo freezing. Results: Based on the result15% to 25% of patients are young premenopausal women. Chemotherapy or radiation therapy can lead to infertility or early menopause. As suggested by evidence, the success rate of embryo freezing is much higher than oocyte freezing and In Vitro Maturation. Among the fertility preservation methods, ovarian tissue freezing and 3D bioprinting are in the laboratory research stage and have received much attention. Correct counseling and providing accurate information to patients and their timely referral have have a marked impact on improving their mental and physical condition and treating their underlying disease. Conclusion: As evidence by the result of this study, early diagnosis of breast cancer and timely referral to a fertility specialist enable , breast cancer patients to maintain their fertility and experience their biological child after aggressive cancer treatments

    Power Maximisation of Wind Energy Using Wind Speed Sensors on Stewart Island

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    This paper evaluates the feasibility of using wind power for power supply to coastal communities isolated from the main supply grid. The case study is Stewart Island, where the cost of electricity provided by a central diesel power station is higher than the grid network in New Zealand. The Princeton Ocean Model (POM) conducted by MetOcean Solutions Limited (MSL) is used to find Foveaux as an optimized site for generating wind power. Global Wind Atlas is used to plot the wind rose of current wind patterns in New Zealand. In the next step, wind speed data from each site are imported from the NASA database to WRPLOT view software and Homer Pro to find wind frequency distribution and output power in the area. The maximum annual power can be seen in WSW (32,299 kW hours/year), SW (20,111 kW hours/year) and W (15,622 kW hour/year) directions, respectively

    Comparison of prescribing indicators of academic versus non-academic specialist physicians in Urmia, Iran

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    Objective: As chief prescribers, physicians could have a key role in rational drug use. Core prescribing indicators of all physicians have been evaluated in the Islamic Republic of Iran for several years, but no study has assessed the effects of academic status of doctors on their prescribing behaviors. We aimed to compare prescribing indicators of two groups of academic and non-academic specialist physicians working in Urmia, Iran. Methods: In this cross-sectional study, prescribing indicators of the total number of 37 academic and 104 non-academic specialist physicians in six medical specialties (infectious diseases, psychiatry, otorhinolaryngology, gynecology, pediatrics and general surgery) were studied during 2012 using Rx-analyzer, a dedicated computer application. A set of five quality indicators was used based on the World Health Organization and International Network for Rational Use of Drugs recommendations. Findings: Totally, 709,771 medications in 269,660 prescriptions were studied. For academic and non-academic specialist physicians, the average number of medications per prescription was 2.26 and 2.65, respectively. Similarly, patients′ encounters with injectable pharmaceuticals were 17.37% and 26.76%, respectively. The corresponding figures for antimicrobial agents were 33.12% and 45.46%, respectively. The average costs of every prescription were 6.53 and 3.30 United States Dollar for academic and non-academic specialist physicians, respectively. All the above-mentioned differences were statistically significant. Conclusion: Better prescribing patterns were observed in academic specialist physicians. However, they prescribed medications that were more expensive, while the reason was not investigated in this study. Further studies may reveal the exact causes of these differences

    Multi-Agent System Based Wireless Sensor Network for Crisis Management

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    Study of ultrastructure and apoptosis in the endometrium of women with or without endometriosis

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    Background: More than 40% of infertilities are due to endometriosis. Ultrustructural and histochemical study of endometrium will help to clarify the etiology of endometriosis. Objective: The aim of the present study was to investigate the ultrastructure and occurrence of apoptosis in endometrial cells of women with or without endometriosis. Materials and Methods: In the present case-control study, endometrial specimens from 12 women without endometriosis (as control) and 12 women with endometriosis (as case) were examined. Specimens for control group were obtained from the patients that were referred to gynecology hospital for hysterectomy due to various reasons. In case group the endometriosis was diagnosed according to laparoscopy and endometrial samples were taken using pippel biopsy. The specimens from both case and control groups were processed for Transmission Electron Microscopy (TEM), TUNEL reaction technique and morphometric studies. Results: The results show that endometrial epithelium lost its continuity in women with endometriosis and endometrial cells have euchromatic nucleus in comparison to those from non–endometriosis. There were several apoptotic cells in the luminal and glandular endometrial epithelium and stroma from endometrium of control group. However, apoptotic cells were rarely seen in the endometrium from women with endometriosis. The difference in number of apoptotic cells between two groups statically was significant (p<0.001).Conclusion: Regarding the ultrastructural characteristics of endometrial epithelial cells and comparison of apoptotic occurrence in control and case groups it is concluded that endometrial cells in endometriosis group have higher potential to survive and possibly implant
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