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In this article, a high-gain two-stage boost converter with improved control is proposed. In order the increase the regulation quality and power density a common control strategy introduced. In the proposed control method, each boost stage is controlled by the same controller. This method provides easy control and low cost and allows the use of lower voltage capacitors at the output of first boost stage. The converter is designed in two stages to increase from 12 VDC input voltage to 42 VDC and 150 VDC. Detailed theoretical analysis of the proposed converter is carried out and validated with a prototype having 100 W output power. Using the results obtained from the application circuit, the proposed boost converter with improved control is compared with the conventional two-stage boost converter operated under the same conditions. [ABSTRACT FROM AUTHOR]

Summary: A novel capacitor‐voltage reduced bidirectional (CVRB) PWM DC‐DC buck‐boost converter is presented in this study. Compared to the conventional bidirectional buck‐boost converter, the proposed converter has a lower voltage rating filter capacitor. Accordingly, the given converter has a lower cost and higher power density than the conventional buck‐boost converter. Additionally, the proposed converter is more efficient due to the direct power transfer feature. Besides, the semiconductor switches have no extra voltage/current stress. The theoretical analysis of the converter is made, and its mathematical analysis is presented. The novel converter is experimentally operated in both the buck and boost modes. The experimental waveforms are shown for both operations. The proposed converter is operated in 100 W output power and 20 kHz switching frequency conditions. The efficiency of the proposed converter is 95.6% for the boost mode operation and 95.1% for the buck mode operation at the nominal output power. [ABSTRACT FROM AUTHOR]

Aim: To investigate the bisphenol A (BPA) levels, which may be a risk factor in the etiology of endometrioma, in patients diagnosed laparoscopically with endometrioma with and without bowel involvement. Method: In the prospective cross-sectional case control study, 47 cases were included in the study, which were admitted to the gynecology and infertility services with and without bowel involvement endometrioma who were operated and diagnosed histopathologically. 43 patients were included in the control group. For serum BPA value, blood samples taken immediately before the operation were studied in laboratory. Patients and controls were compared with controls in terms of serum BPA values. Results: The mean age of the patients was 35 ± 2 in the endometriosis group and 36 ± 2 in the control group which was and not statistically significant. There was no statistical difference between the patient and control groups in terms of menstruation periods. Serum BPA levels were significantly higher in the bowel involvement group compared to the non-bowel involvement group, as the distribution width was higher due to excessive values, and only 5 patients with bowel involvement did not reach statistically significant levels. Serum BPA level was 1084±1132 ng/L in the endometriosis group and 269±99 ng/L in the control group which was statistically significant (p<0,001). Conclusions: BPA levels were showing very wide range especially in the patient group. Serum BPA levels was statistically significantly higher in the endometrioma group compared to the control group. Therefore, in the etiology of endometriosis BPA may take a definite place. [ABSTRACT FROM AUTHOR]

Summary: In this paper, soft switching isolated half‐bridge converter with a new active snubber cell that uses switched capacitor for renewable energy applications is proposed. The proposed snubber cell does not consist any magnetic element so that its structure is quite simple. Furthermore, the auxiliary switches in the proposed active snubber cell are exposed to only half of the input voltage. There is no additional voltage and current stress on any semiconductor devices. All semiconductor power devices in the proposed converter are operated by soft switching. The proposed converter is analyzed thoroughly, and the theoretical analyzes are affirmed by an implementation having 300‐VDC input, 20‐VDC output, 75‐W output power, and 150‐kHz switching frequency. The overall hard switching efficiency of the converter is increased from 86.4% to 92.9% by aid of the proposed soft switching snubber cell. [ABSTRACT FROM AUTHOR]

Background: Inflammatory processes have been considered to be involved in the pathogenesis of endometriosis. However, the predictive role of inflammatory hematological parameters in endometriosis is not clear. The aim of this study was to analyze the clinical value of hematologic markers in the differential diagnosis of endometriomas in younger and older reproductive age women.Materials and Methods: A retrospective chart review was done for 502 patients who underwent surgery: 267 with endometriomas (endometrioma group) and 235 with other benign adnexal cysts (control group). Patients were placed into subgroups as younger (adolescents/young adults, aged <25 years) and older (aged ≥25 years) women. Total and differential white blood cell count, neutrophil-to-lymphocyte ratio, platelet indices and platelet-to-lymphocyte ratio (PLR) were evaluated with receiver operating characteristic curve analysis for differential diagnosis of endometriomas.Results: The mean serum levels of PLR, plateletcrit (PCT), platelet count and CA-125 (reference range below 35 IU/mL) were significantly higher in the endometrioma group (p < 0.001). The area under the curve (AUC) for CA-125 was 0.85 [95% confidence interval (CI), 0.82-0.88] (p < 0.001) for the entire group. However, platelet count, PLR, and PCT showed poor discriminative ability for detecting endometriomas with AUC values of 0.59 (95% CI, 0.55-0.65, p < 0.001), 0.58 (95% CI, 0.53-0.63, p = 0.002) and 0.61 (95% CI, 0.56-0.66, p < 0.001), respectively. In age-stratified analysis, these platelet indices had also low diagnostic performance in both age groups.Conclusions: Hematologic markers do not adequately differentiate ovarian endometriomas from other benign cysts in neither adolescents/young adults nor older women. [ABSTRACT FROM AUTHOR]

This paper introduces a novel modular active snubber cell for isolated half-bridge converters with ease of control. The novel snubber cell can achieved soft switching for all semiconductors at the proposed converter. The switches in the converter are derived simultaneously by the normal pulse-width modulation signals. The introduced snubber cell has a quite simple structure and ease of control. In this converter, the main switches turn on with zero current switching and turn off with zero voltage switching. Besides, there is no extra voltage stresses on the power elements. The proposed half-bridge DC–DC converter is analyzed in detail and its theoretical analysis is verified with a prototype having 50 A–25 V output values at 80 kHz frequency. [ABSTRACT FROM AUTHOR]

In this paper, a new modular and active snubber cell, easily applicable, and attractive for converters, especially have many switches proposed. This snubber cell is implemented on the single phase of a grid-connected three-phase T-type three-level inverter (T-3LI). In this new converter, the main switches turn-on under zero-voltage transition and turn-off under zero-voltage switching (ZVS). Also, auxiliary switches turn-on under zero-current switching and turn-off under ZVS. All snubber diodes operate under soft switching (SS). There are no additional current and voltage stresses on the main switches. During an SS operation, the switching energies are transferred to a dc voltage source. Then, these energies are processed to input with an independent dc–dc converter. Thus, all switching energies are recycled. In this paper, the principle operation and steady-state analysis of the modular and active snubber cell for a single-phase T-3LI are presented and experimental results, rated 1 kW and 100 kHz, are provided to verify theoretical analysis. [ABSTRACT FROM AUTHOR]

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We report the case of the women who has vaginal evisceration after hysterectomy with history of abdominoplasty. A 45-year-old female presented to the emergency department complaining of a mass protruding through her vagina. Clinical examination revealed vaginal vault rupture with intestinal herniation per vagina. Gynecologists as well as all involved caregivers should be aware of this rare, but potentially life-threatening condition, as early recognition is crucial for a favorable outcome. [ABSTRACT FROM AUTHOR]

Background: Inflammatory processes have been considered to be involved in the pathogenesis of endometriosis. However, the predictive role of inflammatory hematological parameters in endometriosis is not clear. The aim of this study was to analyze the clinical value of hematologic markers in the differential diagnosis of endometriomas in younger and older reproductive age women., Materials and Methods: A retrospective chart review was done for 502 patients who underwent surgery: 267 with endometriomas (endometrioma group) and 235 with other benign adnexal cysts (control group). Patients were placed into subgroups as younger (adolescents/young adults, aged <25 years) and older (aged ≥25 years) women. Total and differential white blood cell count, neutrophil-to-lymphocyte ratio, platelet indices and platelet-to-lymphocyte ratio (PLR) were evaluated with receiver operating characteristic curve analysis for differential diagnosis of endometriomas., Results: The mean serum levels of PLR, plateletcrit (PCT), platelet count and CA-125 (reference range below 35 IU/mL) were significantly higher in the endometrioma group (p < 0.001). The area under the curve (AUC) for CA-125 was 0.85 [95% confidence interval (CI), 0.82-0.88] (p < 0.001) for the entire group. However, platelet count, PLR, and PCT showed poor discriminative ability for detecting endometriomas with AUC values of 0.59 (95% CI, 0.55-0.65, p < 0.001), 0.58 (95% CI, 0.53-0.63, p = 0.002) and 0.61 (95% CI, 0.56-0.66, p < 0.001), respectively. In age-stratified analysis, these platelet indices had also low diagnostic performance in both age groups., Conclusions: Hematologic markers do not adequately differentiate ovarian endometriomas from other benign cysts in neither adolescents/young adults nor older women., (©2018 Walter de Gruyter GmbH, Berlin/Boston.)

Background: Relationships between poor prognosis of ovarian malignancies and changes in complete blood count parameters have been proposed previously. In this work, we aimed to evaluate clinicopathologic features in adolescents with adnexal masses and sought to establish any predictive value of the platelet to lymphocyte ratio (PLR) in diagnosis., Materials and Methods: This retrospective study was conducted on 196 adolescent females with adnexal masses. Three groups were constituted with respect to clinical or histopathology results: group 1, non-neoplastic patients (n:65); group 2, neoplastic patients (n:68); and group 3 expectantly managed patients (n:63). The main parameters recorded from the hospital database and patient files were age, body mass index (BMI), chief symptoms, diameter of the mass (DOM), tumor marker levels, complete blood count values including absolute neutrophil, lymphocyte, and platelet counts, mean platelet volume, platelet distribution width, and platecrit, surgical features, and postoperative histopathology results., Results: The expectantly managed patients were younger than the other groups (p=0.007). The mean body mass index (BMI) was higher in the neoplastic group (p=0.016). Preoperative DOM, CA125, mean platelet volume and PLR were statistically significantly different between the groups (p<0.05). ROC curve analysis demonstrated that increased PLR (AUC, 0.609; p=0.011) and BMI (AUC, 0.611; p=0.011) may be discriminative factors in predicting ovarian neoplasms in adolescents preoperatively. When the cut-off point for the PLR level was set to 140, the sensitivity and specificity levels were found to be 65.7% and 57.6%, respectively., Conclusions: We suggest that beside a careful preoperative evaluation including clinical characteristics, ultrasonographic features and tumor markers, PLR may predict ovarian neoplasms in adolescents.

Background: To evaluate factors for predicting the granulosa cell tumor of the ovary (GCTO) pre-operatively., Materials and Methods: This retrospective designed study was conducted on 34 women with GCTO as the study group and 76 women with benign ovarian cysts as the control group. Data were recorded from the hospital database and included age, body mass index (BMI), parity, serum estradiol (E2) levels, diameter of the mass, ultrasonographic features, serum CA125 level, risk of malignancy index (RMI), duration of menopause, postoperative histopathology result, and the neutrophil/lymphocyte ratio (NLR)., Results: The demographic parameters showed no statistically significant difference between the groups. Preoperative diameter of the mass, CA125, duration of menopause, and neutrophil/lymphocyte ratio were significantly different between the groups. ROC curve analysis demonstrated that diameter of the mass, serum estradiol and Ca125 levels, RMI and NLR may be discriminative factors in predicting GCTO preoperatively., Conclusions: In conclusion, we think that a careful preoperative workshop including diameter of the mass, serum estradiol (E2) and Ca125 levels, RMI and NLR may predict GCTO and may prevent incomplete approaches.