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This study investigates the beta irradiation's impact on the electrical features of interfacial nanostructures composed of poly(vinyl alcohol) (PVA) doped with graphene. The integration of graphene, a 2D carbon allotrope renowned for its exceptional electrical conductivity, into PVA nanostructures holds significant promise for advanced electronic applications. Beta irradiation, as a controlled method of introducing radiation, offers a unique avenue to modulate the properties of these nanostructures. Therefore, this study examines the Au/3% graphene(Gr)-doped PVA/n-type Si structure with and without beta (ß) radiation. The effect of beta radiation on the electrical properties of the Au/3% graphene(Gr)-doped PVA/n-type Si structure has been researched by utilizing the current-voltage (I-V) data. The studied structures were exposed to a 90Sr ß-ray source at room temperature to show the effect of beta radiation. The series resistance (R s), shunt resistance (R sh), ideality factor (n), barrier height (BH) (ΦB0), and saturation current (I o) were computed using the I-V data after 90Sr ß-ray irradiation (0, 6, and 18 kGy) and before using the thermionic emission, Norde, and Cheung methods. The BH, ideality factor, and series resistance were calculated using the I-V data as follows: 0.888 eV, 3.21, and 5.25 kΩ for 0 kGy; 0.782 eV, 5.30, and 3.47 for 6 kGy; 0.782 eV, 5.46, and 2.63 kΩ for 18kGy. The BH, ideality factor, and series resistance were also calculated using the Cheng Methods, and the following results were found respectively: 7.22, 0.74, and 3.97 kΩ (Cheng I), and 3.22 kΩ (Cheng II) for 0 kGy; 5.14, 0.813, and 2.72 kΩ (Cheng I), and 2.14 kΩ (Cheng II) for 6 kGy; 6.78, 0.721, and 1.96 kΩ (Cheng I), 1.64 kΩ (Cheng II) for 18 kGy. The BH and series resistance were defined as 0.905 and 16.12 kΩ for 0 kGy, 0.859 and 5.31 kΩ for 6 kGy, and 0.792 and 2.49 kΩ for 18 kGy, respectively. Interface states density (N ss) as a function of E c-E ss was also attained by taking into account the voltage dependence of n, ΦB, and R s. Experimental results showed that the values of n and N ss increased with an increase in the ß-ray radiation dose. On the other hand, the saturation current (I o), ΦB0, and R s values decreased with the increase in the ß-ray radiation dose. The obtained results indicate a nuanced interplay between ß irradiation dose and the nanostructure's overall electrical properties. Insights gained from this study contribute to the understanding of radiation-induced effects on graphene-doped polymer nanostructures, providing valuable information for optimizing their performance in electronic applications.
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Objective: To compare the rates of blastocyst stage development between embryos fertilized after one (MPN) or more than two pronucleus (PN) (3PN, 4PN-multiPN) with those after 2PN in the same patients. Material and Methods: The embryos of patients who had both abnormal PN (MPN, 3PN or 4PN) and normal fertilized (2PN) embryos after intracytoplasmic sperm injection (ICSI) fertilization, were followed with a time-lapse system following the ICSI procedure. The rates of reaching the blastocyst stage were compared between normal and abnormally fertilized embryos. Results: One thousand eight hundred and twenty oocytes were collected from 140 patients and 1280 (70.3%) of them were fertilized. MPN, 2PN and 3PN, 4PN (multiPN) ratios of the embryos in the pronuclear stage were 11.4%, 83.13% and 5.47%, respectively. The rates of reaching the blastocyst stage among these embryos were 17.1%, 60.8% and 42.8% for MPN, 2PN and multiPN, respectively. The proportion reaching blastocyst development was significantly higher following 2PN compared to those after MPN and multiPN (p<0.05). Embryos developing after multiPN had significantly higher rates of reaching the blastocyst stage compared to those after MPN (p<0.01). Conclusion: The majority of abnormally pronucleated embryos arrest without reaching the blastocyst stage. MultiPN embryos have a higher rate of blastocyst development than MPN embryos.
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BACKGROUND: T- shaped uterus may be associated with infertility and adverse pregnancy outcomes. Hysteroscopic metroplasty may improve the reproductivity for these cases. To our knowledge, there is no data in literature about the clinical consequences of in vitro fertilization (IVF) in patients undergoing hysteroscopic metroplasty for T-shaped uterus. The principal objective of the current study is to assess the impact of hysteroscopic metroplasty for T-shaped uterus on the reproductive outcomes of IVF. METHODS: IVF outcomes of 74 patients who underwent hysteroscopic metroplasty for T- shaped uterus and 148 patients without any uterine abnormalities and with diagnosis of unexplained infertility (control group) were retrospectively analyzed. RESULTS: Patients in metroplasty and control groups were comparable with respect to age, BMI, partner's age and duration of infertility. Number of patients with a history of pregnancy beyond 20 weeks of gestation was significantly lower in the metroplasty group (4.1% vs 18.2%; p < 0.05). Number of previous unsuccessful cycles and percentage of patients with ≥3 unsuccessful IVF cycles (35.1% vs 17.6%; p < 0.05) were significantly higher in the metroplasty group. There were no significant differences in the reproductive outcomes such as the pregnancy rate, clinical pregnancy or live birth rate between the metroplasty and control groups. There were non-significant trends for higher rates of miscarriage (18.8% vs 8%, p > 0.05) and biochemical pregnancy (20.0% vs 10.7%, p > 0.05) in the metroplasty group compared to the control group. CONCLUSIONS: Reproductive results of the IVF cycles after hysteroscopic correction of T-shaped uterus were comparable to those of the patients without any uterine abnormalities and with diagnosis of unexplained infertility. Hysteroscopic metroplasty may contribute to improved IVF outcomes in patients with T-shaped uterus.
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While patients with obstructive sleep apnea (OSA) or multiple sclerosis (MS) are at high risk of developing postoperative complications, both of them have special anesthetic considerations in intraoperative and postoperative periods. A careful preoperative evaluation, use of the optimal anesthetic regimen and close postoperative care is essential for these patients. Rarity of coexistence of both obstructive sleep apnea and multiple sclerosis in a surgical patient necessitates careful anesthetic management. We here report anesthetic management of a female patient with OSA and MS who underwent anesthesia three times for surgery and review the literature.
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AIMS: The purpose of this study was to investigate correlations between first trimester placental volume (PV) and blood flow indexes (FIs), bilateral uterine artery pulsatility indexes, notching, and biochemical parameters: pregnancy-associated plasma protein-A (PAPP-A), free beta-human chorionic gonadotropin (f-ß-hCG), and insulin-like growth factor-1 (IGF-1) to predict the high-risk pregnancies in the first trimester. METHODS: We prospectively examined 310 patients at 11-14 weeks of pregnancy using transabdominal 3D gray scale and power Doppler ultrasound for assessing PV, vascularization index, FI, and vascularization FI (VFI). The acquired volumes were analyzed using VOCAL™ imaging software. The results were correlated with biochemical parameters. RESULTS: We found significant correlations between PV and biochemical parameters, and between placental blood flow studies and other parameters. Finally, PV/crown-rump length so called the placental quotient is also related to both PAPP-A and VFI. CONCLUSIONS: Placental volumetry, uterine artery Doppler studies, blood flow calculations and biochemical parameters, such as f-ß-hCG, PAPP-A, and IGF-1 could be important in the early and rapid diagnosis of high-risk pregnancies. Thus, they may be useful in first trimester prediction of fetal growth restriction presenting with alterations in PV and vascularity.
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Gonadotropina Coriônica Humana Subunidade beta/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Proteína Plasmática A Associada à Gravidez/metabolismo , Adulto , Velocidade do Fluxo Sanguíneo , Estatura Cabeça-Cóccix , Feminino , Retardo do Crescimento Fetal/diagnóstico , Humanos , Imageamento Tridimensional , Valor Preditivo dos Testes , Gravidez , Primeiro Trimestre da Gravidez , Gravidez de Alto Risco , Estudos Prospectivos , Fatores de Risco , Ultrassonografia Doppler , Ultrassonografia Pré-Natal , Artéria Uterina/diagnóstico por imagem , Adulto JovemRESUMO
Pyometra is the accumulation of purulent material in the uterine cavity. Its reported incidence is 0.01-0.5% in gynecologic patients; however, as far as elderly patients are concerned, its incidence is 13.6% [3]. The most common cause of pyometra is malignant diseases of genital tract and the consequences of their treatment (radiotherapy). Other causes are benign tumors like leiomyoma, endometrial polyps, senile cervicitis, cervical occlusion after surgery, puerperal infections, and congenital cervical anomalies. Spontaneous rupture of the uterus is an extremely rare complication of pyometra. To our knowledge, only 21 cases of spontaneous perforation of pyometra have been reported in English literature since 1980. This paper reports an additional case of spontaneous uterine rupture.
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Dor Abdominal/etiologia , Ruptura Espontânea/complicações , Doenças Uterinas/complicações , Ruptura Uterina , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , SupuraçãoRESUMO
BACKGROUND: Although seasonal variation of birth weight has been reported previously, contributing factors such as the meteorological factor and its specific period of exposure remain unclear. AIM: To investigate the effect of season on birth weight and to determine the meteorological factor and its specific period of exposure which can contribute to any seasonal variation in birth weight. METHODS: Retrospective analysis of 3333 singleton live births after 36 completed weeks of pregnancy. Maternal age, parity, route of delivery, sex and individual meteorological variables for the first, second, and third trimesters of each pregnancy were analysed using multiple regression analysis with the birth weight as the dependent variable. RESULTS: A seasonal pattern was observed with lowest birth weights in women who had their last menstrual periods in summer and autumn. Upon multiple regression analysis, sex, parity, mode of delivery, and the temperature which the mother was exposed to in the second trimester were the independent determinants of birth weight. CONCLUSION: Exposure to low outdoor ambient temperature in the midtrimester can be associated with low birth weight.