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We present state of art first-principles study on the static and dynamic properties of BaTiO3, a typical ferroelectric material. Here, structure, equation of state, phase stability, and phase transformations of BaTiO3 studied in Generalized Gradient Approximation. Furthermore, properties such as, Born effective charges, optical dielectric constant and phonon spectra are calculated from Density Functional Perturbation Theory. [ABSTRACT FROM AUTHOR]

We present state of art first-principles study on the static and dynamic properties of BaTiO3, a typical ferroelectric material. Here, structure, equation of state, phase stability, and phase transformations of BaTiO3 studied in Generalized Gradient Approximation. Furthermore, properties such as, Born effective charges, optical dielectric constant and phonon spectra are calculated from Density Functional Perturbation Theory. [ABSTRACT FROM AUTHOR]

The rapid solidification of Pd-Ni alloys is studied with the constant-pressure and constant-temperature (TPN) and the constant-volume and constant-temperature (TVN) molecular dynamics technique to obtain an atomic description of glass formation in the alloy. Quantum Sutton-Chen potential for Pd-Ni binary system is applied in the simulations. We present some thermodynamic and structural results from simulations of such glasses over a range of compositions. The structural properties are analyzed by means of pair distribution function, volume, and enthalpy as a function of temperature and concentration at the cooling rates ranging from 5 K/ps to 0.05 K/ps to see whether the Pd-Ni alloy goes into glass formation or it crystallizes. The relation between the cooling rate and glass transition temperature is revealed. We have also investigated shear viscosity in the supercooled regime. Its temperature dependence indicates fragile-liquid behavior, typical of binary metallic glasses. The results shows that the atomic mismatch and having the eutectic composition are important parameters to form glassy state. [ABSTRACT FROM AUTHOR]

Background: So far, many studies investigated factors that affect pregnancy rates after intrauterine insemination (IUI). Various investigators have not agreed on the nature and ranking of these criteria., Objective: The aim of this study was to assess the predictive factors for pregnancy rate after controlled ovarian hyperstimulation (COH)/ IUI., Materials and Methods: Retrospective study of all patients undergoing IUI at Zeynep Kamil Gynecologic and Pediatric Training and Research Hospital from January 2006 to December 2009. In total 980 IUI cycles in 569 couples were analyzed. All women in the study underwent ovarian stimulation using gonadotropin and IUI was performed 36 h after triggering ovulation. The primary outcome measure was clinical pregnancy rates. Predictive factors evaluated were female age, body mass index (BMI), duration of infertility, type of infertility, follicle stimulating hormone (FSH) level and estradiol (E2) on third day of the cycle, number of preovulatory follicles, endometrial thichness, total motil sperm (TMS) count, and ratio of progressive motile sperm., Results: The overall clinical pregnancy rate was 4.7%. Among the predictive factors after multivariate logistic regression analysis level of BMI (<25 kg/m²), number of preovulatory follicles (≥2), level of FSH (<9.4 IU/L), level of E2 (<80 pg/ml) and the ratio of progressive motile sperm (>50%) significantly influenced the clinical pregnancy rate., Conclusion: Level of BMI, FSH, estradiol, number of preovulatory follicles and the ratio of progressive motile sperm may determine IUI procedure as optimum treatment model.

Objective: Gonadotropins used in controlled ovarian stimulation have been increasing in number. Beside the recombinant preparations such as rec-FSH, rec-LH and h-hMG human-derived preparations have entered the market. We decided to compare the effects of rec-FSH and HP-hMG with GnRHa on embryo quality and pregnancy outcome in women undergoing an IVF cycle., Material and Methods: In this study, data of 87 patients who had applied to our center from 2007 to 2008 and who had met all inclusion criteria, were analyzed. The patients underwent controlled ovarian hyperstimulation with HP-hMG, rec-FSH following down-regulation with a GnRHa in a long protocol, selected according to determined criteria and acquired embryo via IVF transfer., Results: Of the 87 patients, 44 were stimulated with rec-FSH and 43 with HP-hMG. Distribution of infertility causes was similar between the groups. Duration of gonadotropin administration (p=0.677, Student's t-test) and the total dose of gonadotropin received (p=0.392, Student's t-test) were similar between the two groups. The fertilization rate of the rec-FSH group was significantly higher than the HP-hMG group (p=0.001, Mann-Whitney U test). No significant differences were observed between the study groups in biochemical, clinical and ongoing pregnancy parameters., Conclusion: The higher oocyte yield with rec-FSH does not result in higher quality embryos. LH activity in combination with FSH activity positively affected the oocyte and embryo maturation. Therefore, when we consider the clinical and ongoing pregnancy rates there is no inferiority of HP-hMG in controlled ovarian stimulation.

Objective: Iniencephaly is a rare neural tube defectwith consisting of a defect in the occipital bone,spina bifida of many vertebrae, and retroflexion of the head on the spine. In majorty of cases it is a le-\thal condition., Methods: We present the first case of iniencephalywith large bronchogenic cyst diagnosed prenatally., Results: At 19 week's gestation showed that fetalcardiac activity was present with normal placentaand amniotic fluid, fetus had occipital bone defect, anencephaly, retroflexion of the head, abnormally short cervicothoracic spine and posterior mediastinal unilocular anechoic cyst. Therapeutic abortion was induced., Conclusion: Iniencephaly is a rare condition during prenatal life. When diagnosed early in pregnancy amultidisciplinary approach is firmly suggested.

Objective: To examine and to compare postpartum maternal and neonatal complications and morbidities in women with HELLP syndrome (HELLP group) and women with severe preeclampsia without HELLP syndrome (severe preeclamptic group)., Methods: In this retrospective study, 111 patients in the HELLP group were matched with 467 patients in the severe preeclamptic group according to maternal and neonatal complications and morbidities., Results: The rate of transfusion of blood products and acute renal failure was significantly greater in women with HELLP syndrome. One maternal mortality (0.9 % ) was found in women withHELLP syndrome, and no maternal mortality in women in severe preeclamptic group a. There were significant differences between the HELLP group and the severe preeclamptic group in neonatal mortality and morbidity. It was found that HELLP syndrome cases had significantly lower gestational age and fetal bodyweight. The simultaneous presence of HELLP syndrome and preeclampsia, along with oliguria, ascites, thrombocytopenia, elevated liver enzymes and caesarean delivery, was associated with post-partum complications., Conclusion: This study shows that maternal and neonatal morbidity and mortality are increased in pregnancies complicated by severe preeclampsia with HELLP syndrome. Neonatal mortality and morbidity appear to be influenced primarily by gestational age at delivery.

Iniencephaly is a rare but almost always lethal neural tube defect with the following cardinal features: occipital bone defect, partial or total absence of cervicothoracal vertebrae and fetal retroflexion. Iniencephaly is associated with malformations of the central nervous system, gastrointestinal and cardiovascular system. Prenatally diagnosed cases of iniencephaly are rare because careful and early ultrasonographic evaluation is necessary. The present cases of iniencephaly were found to carry associated malformations such as atrioventricular septal defect and club foot. We present an iniencephaly prenatally diagnosed by sonography, in which therapeutic abortion was induced, with a review of the published literature.

A 32-year-old woman, gravida 4, para 2, was diagnosed with a benign right ovarian mucinous cystadenoma. It was diagnosed in the tenth week of pregnancy, measured 47 x 69 mm, and reached 190 x 152 mm at 23 weeks of gestation. Laparotomy was performed and the ovarian cystic mass was removed in the second trimester. The patient had postoperative tocolytic therapy and progesterone medication. She is at the 35th gestation week and no other antenatal complication has been reported. A case of giant mucinous cystadenoma is presented with clinical follow-up details.