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An onboard charger segment is currently dominated by two-stage charger designs, which suffer from drawbacks such as large size, low efficiency due to a high component count, elevated cost, and intricate controller requirements. To address these challenges, this work explores the implementation of an isolated bridgeless version of a modified single-ended primary inductor converter (SEPIC). This innovative approach aims to develop a single-stage, high-power factor battery charger tailored for light electric vehicles (LEVs). In addition to achieving high power factor operation, maintaining continuous input and output currents, and enabling high voltage conversion ratios, this charger utilizing modified SEPIC converter is specifically engineered to alleviate voltage stress on power switches within the converter circuit. This charger operates in discontinuous conduction mode (DCM), offering several notable advantages. These include inherent power factor correction capability, reduced control effort, minimized size of magnetic components, and fewer sensors, ultimately leading to a significant reduction in overall implementation cost. This article aims to validate charger's operation, elaborate on design of its components, outline control algorithm design, and demonstrate performance of both components and control logic through test results from hardware prototype developed, for a power level of 500 W.

This article presents a modified single-ended primary inductance converter based single-stage ac–dc converter designed specifically for low voltage electric vehicles (LVEVs) charger applications. The rectifier showcases in this article demonstrates a high-step down buck gain, making it ideal for charging low-voltage battery packs commonly found in LVEVs. By utilizing a bridgeless structure at the input side with simultaneously operated switches, the converter reduces control complexity and eliminates the need for input voltage polarity sensing, a requirement in conventional continuous inductor current mode converters. The converter's extended step-down gain is achieved through switched-inductor structures, enabling it to deliver the required battery charging profile for low-voltage battery packs. Operating the inductors in discontinuous inductor current mode not only facilitates intrinsic power factor correction capabilities at the grid side but also reduces the size of magnetic components. DICM operation also provides zero-current turn-on for switches and zero-current turn-off capability for high-frequency diodes, thereby minimizing losses associated with diode reverse-recovery transitions. During testing on a proof-of-concept testbench at a power level of 450 W, the converter demonstrated a peak efficiency of 94.2% at rated power. In addition, the total harmonic distortion in input current was measured at 3.4%, showcasing a unity power factor and good power quality (PQ) indices at the grid. These results highlight the effectiveness of the converter in maintaining proper battery charging profiles while ensuring high efficiency and PQ standards in LVEV charging applications.

A single-switch modified SEPIC bridgeless coupled switched inductor-based charger, for charging applications of low voltage electric vehicles (LVEVs) is demonstrated in this work. Presented charger achieves higher step-down gain between the AC grid and the DC battery pack output without requirement of a step-down transformer, using a coupled switched inductor structure. The discontinuous inductor current mode (DICM) operation of charger reduces the magnetic volume, thus making it compact. The DICM operation adds advantages of inherent power factor correction (PFC) at the input side, without requirement of additional input sensing circuitry. Added to this, DICM operation facilitates zero current turn-on and zero-current turn off for switches and diodes in the charger, respectively, which reduces switching losses associated with high frequency components. Lastly, the design, operating modes and performance of charger is verified through development of a prototype and results obtained are presented in this work.

A charger topology using a single stage and transformer-less design employing bridgeless semi quadratic voltage gain with high power factor (HPF) AC-DC converter, is demonstrated in this article for light electric vehicles (LEVs). In order to achieve transformer-less structure and wide voltage gain (particularly step-down gain) between high AC input and low DC output (LEVs battery packs), an integrated structure comprising of a bridgeless SEPIC (single ended primary inductor converter) and a buck converter, is effectively utilized to achieve desired charging characteristics at the battery end and maintaining high power factor at AC end of the charger. The bridgeless along with the transformer less structure, together helps in reducing the size, and the cost of the charger and to improve its overall efficiency. Further, the discontinuous inductor current mode (DICM) operation optimizes the volume of magnetics, facilitates power factor correction inherently at the input and ensures zero current switching of semiconductor devices, without having to provide additional control or circuit modifications. This work gives a comprehensive, theoretical, and mathematical analysis of the concepts and advantages of the presented topology, with proper design of its active and passive components. Lastly, the performance of the charging circuitry is verified using a proof-of-concept hardware setup and corresponding results are discussed for performance verification. Moreover, the comparative analysis of the presented charger with state-of-art chargers and converter topologies is carried out to justify the distinctive properties of former one compared to the latter one.

Purpose: To find out whether additional interstitial component provides better dose distribution and less organ at risk (OAR) doses compared to treatment plan without needles for locally advanced carcinoma cervix cases with residual disease after chemoradiation. Methods: Nine patients with residual disease after chemoradiation for locally advanced cancer cervix were selected for MRI-based brachytherapy planning with hybrid intracavitary/interstitial (IC/IS) Utrecht applicator. The doses of external beam radiotherapy and brachytherapy were added and converted to 2 Gy dose equivalent (EQD2). Two additional sets of plans were created for each patient with and without optimization, before incorporating the interstitial component. A dosimetric comparison was carried out between the plans. Results: The mean high-risk clinical target volume (HRCTV) D90 dose was 87.78 Gy, and HRCTV D98 was 77.4 Gy for the combined IC/IS plans. The mean 2 cc rectal, bladder, and sigmoid doses were 61.3 Gy, 82.2 Gy, and 57.02 Gy, respectively. The mean D90 and D98 doses for plans without optimization were 90.01 Gy and 78.61 Gy, and for optimized plans were 89.8 Gy and 78.03 Gy, respectively. The corresponding 2 cc rectal, bladder, and sigmoid doses were 76.54 Gy, 99.48 Gy, and 69.58 Gy, respectively, for non-optimized plans and 76.1 Gy, 101.94 Gy, and 69.5 Gy, respectively, for optimized plans. The differences of doses of OAR were significantly favoring IC/IS plans with p-value of 0.027, 0.025, and 0.044 for D2cc of bladder, rectum, and sigmoid, respectively. Conclusion: The combined IC/IS plans with optimization resulted in statistically significant lower OAR doses while maintaining the optimal HRCTV doses compared to the intracavitary alone plans with or without optimization.

A single-stage AC-DC converter, which uses a quadratic buck-boost voltage gain, for LEVs’ (Light Electric Vehicles) battery charging is presented in this work. Unlike conventional BCs (Battery Chargers), which employ transformer (low or high frequency) based approaches to charge low voltages LEVs’ batteries, the presented charger utilizes transformerless single-stage power architecture. In order to realize desired charging of LEVs and to maintain proper transformerless voltage gain, the presented quadratic buck-boost AC-DC converter ensures high step-down gain characteristics between AC mains and low voltage battery packs. Besides realizing desired battery charging profile, the presented single-stage BC ensures high PQ (Power Quality) indices (low input current distortions and unity power factor operation) at the supply side. Notably, the presented quadratic buck-boost AC-DC converter exhibits an intrinsic power factor correction (PFC) feature at the AC input mains under discontinuous inductor current mode (DICM) operation, thereby, incurring minimum complexities during the control implementation, which further reduces the cost of the charger. The DICM operation facilitates negligible switch turn-on and diode reverse recovery losses, and therefore, ensures an improved conversion efficiency of the BC. Even if, the presented AC-DC converter employs two switching devices, the simultaneous switching of both switches shrinks the cost and complexity of driving circuitry even further. Finally, a comprehensive operational analysis, component selection criteria, and modelling of the presented quadratic buck-boost AC-DC converter-based LEVs BC are carried out and its performance is validated through a test bench set-up in a laboratory environment. Relevant results are presented to validate the efficacy of the presented quadratic buck-boost AC-DC converter for LEVs charging applications.

Abstract: Uterine sarcomas are heterogeneous group of tumours comprising 1% of gynaecological malignancies. There is lack of concences on optimal treatment of uterine sarcomas. This is because of lack of randomised controlled trials due to rarity of these tumours. Surgical management without spill remains the standard primary treatment. Most of the times uterine sarcomas are diagnosed postoperatively from histopathology report of either myomectomy or hysterectomy. This retrospective study analysed the clinico pathological characteristics, prognostic factors, treatment details and survival outcome of different types of uterine sarcomas. Materials and methods: This is a retrospective analysis of 59 patients of uterine sarcomas. All patients underwent surgery. Adjuvant chemotherapy or radiation treatment were given according to histopathological report and FIGO stage. Patients were followed up every three months for first two years and then every six months. Disease free survival (DFS) and Overall survival (OS) were calculated. Statistical analysis: The data were summarized using descriptive statistics as mean, percent and range. Survival probabilities were estimated using Kaplan–Meier method and the significance of difference between the survival curves were calculate using log-rank test. Results: Uterine sarcomas are rare and aggressive tumours of uterus. Majority of these tumours present in early stage. Surgery remains the main treatment modality. Role of adjuvant radiation treatment remains controversial. Tumour stage is the most important prognostic factor.

Though survival in bilateral retinoblastoma (RB) has improved due to advancement in diagnostics and treatment modalities, children require long-term follow-ups for recurrence and second malignancies. We report a case of bilateral RB in a 7-month-old baby who was treated with chemotherapy, transpupillary thermotherapy, and periocular carboplatin for both eyes following which there was complete regression of tumour. Six and a half years after treatment, the child presented with metastatic recurrence of tumour in the left ulna. He was treated successfully with chemotherapy, extracorporeal radiation and reimplantation therapy. A less aggressive treatment approach for isolated bone relapse may be considered in selected cases.

•The proposed improved power quality charger is designed and implemented for a wide input-output voltage range condition, and therefore, it provides a general purpose charging solution to different categories of E2Ws and E3Ws.•The presented charger incorporates design and control simplicity, high efficiency and cost effectiveness, and therefore, realize high performance low cost compact charging solution for E2Ws and E3Ws.•Notably, the presented charger exerts minimum stress on existing power system by realizing low supply current harmonics distortions and high operating power factor charactiersics at AC end over wide range of operating condition.•Considering these features, the working principle, design, control, and implementation of the presented charging solution is carried out comprehensively and discussed in the attached manuscript.

Adenoid cystic carcinoma of vulva (ACC-vulva) is an extremely rare entity with <100 cases reported in the literature so far. To study the clinical profile and outcome of ACC-vulva treated at a tertiary cancer care centre in South India. This is a retrospective, record-based study of histopathologically confirmed cases of ACC-vulva treated at our centre from January 2005 to March 2016. Only four patients were diagnosed with ACC-vulva during the 11-year period under study. The longest duration of follow-up was 129 months. The age at diagnosis ranged from 32 to 43 years, with a median of 40 years. All patients were married, parous and premenopausal and presented with a painless unilateral vulval swelling. All patients had involvement of the Bartholin’s gland site with normal overlying skin. In all patients, wide excision was performed. Unilateral inguinal node dissection was done in one case. Perineural infiltration was documented in two cases, while positive excision margins were present in three cases. None of the patients had any lymph node involvement at diagnosis or during follow-up. Two patients had recurrence of disease. The disease-free interval was 23 months for one patient and 118 months for the other. In both, local (vulval) and distant (multiple lung) metastases were detected simultaneously. Adenoid cystic carcinoma of vulva is an extremely rare, slowly progressing neoplasm mostly involving the Bartholin’s gland. The usual treatment includes wide excision and adjuvant radiotherapy (if required). There may be late local and distant recurrence.

Purpose: To analyze the feasibility of fertility-sparing surgery in patients who received neoadjuvant therapy for advanced malignant germ cell tumor of the ovary and to assess the menstrual and reproductive function in such patients. Methods: A retrospective study of 28 patients who underwent cytoreductive surgery following neoadjuvant chemotherapy for advanced germ cell tumor of the ovary from January 2008 to March 2019. Results: The median age of the patients was 16.5 years. All patients responded well to neoadjuvant chemotherapy. Twenty-four patients underwent fertility-sparing surgery. Two patients opted for hysterectomy and bilateral salpingo-oophorectomy as they had completed their family and two patients underwent bilateral salpingo-oophorectomy for residual disease. One patient underwent completion surgery at a later date for a large benign cyst of the remaining ovary. Two patients were lost to follow-up, one of whom was pregnant at the time of the last follow-up. One patient, who initially presented with stage IV Dysgerminoma died due to disease recurrence. Of the remaining patients, 16 reported regular menstrual cycles and one patient has irregular cycles. Two patients were diagnosed with primary amenorrhea and two are still premenarchal. Three patients tried for pregnancy and had a total of four pregnancies. Conclusion: When fertility preservation is not feasible, neoadjuvant chemotherapy followed by surgery might be considered in patients with advanced malignant germ cell tumor. Neoadjuvant chemotherapy followed by surgery can result in complete cytoreduction, with high chance of fertility preservation and good menstrual and reproductive outcome.

Purpose: The purpose of the study was to identify the clinicopathological factors associated with recurrence in patients who underwent primary surgical management for carcinoma endometrium stage I to IVA. Methods: Retrospective analysis of data of 642 patients who underwent surgery with or without adjuvant therapy for carcinoma endometrium during the period January 2009 to December 2013 was performed. The five-year disease-free survival (DFS) and locoregional relapse-free survival (LR-RFS) were calculated using the Kaplan–Meier method. Log-rank test, univariate cox regression analysis, and multivariate analysis were conducted to find out the significance of different factors on outcome. Results: The five-year DFS of the study population was 82.1%, and LR-RFS was 93.2%. Age more than 60 yrs, high-grade tumor, advanced stage, deep myometrial invasion, cervical stromal invasion, and negative PR status were independent prognostic factors for disease-free survival for carcinoma endometrium in multivariate analysis. Locoregional relapse-free survival was affected by cervical stromal invasion, negative PR status, and the lack of adjuvant treatment. Conclusion: Traditional clinicopathological risk factors stage, grade, age, and lack of PR expression were predictive of recurrence and can guide us in deciding adjuvant treatment until newer molecular classifications are proved better.

Yellow phosphorous is one of the most common toxins reported to cause fulminant hepatic failure. Yellow phosphorous is a component of rodenticides and fireworks, and is freely available over the counter. The mortality rate as high as 27% from fulminant hepatic failure has been reported following ingestion of yellow phosphorous.1Multisystem toxicity affecting gastrointestinal, cardiac, renal and central nervous systems occurs.2There is a paucity of literature on its haematological toxicity. In this case report, we highlight the clinically significant myelosuppression observed in a patient resulting from yellow phosphorous; a small literature review has also been done on this rare complication.

Objective: The objectives were to study the pattern of expression of PD-L1 in patients with carcinoma cervix and find out any relation with the various patient- and disease-related factors like histology, FIGO stage, lymph node metastasis and response to treatment. Methods: One hundred cervical cancer patients registered during 2018 who were suitable for radical treatment were identified. The paraffin-embedded, formalin-fixed cervical biopsy specimens of these patients were collected. Immunohistochemical staining for PD-L1 expression was performed on the cervical biopsy material. The test was considered positive if 50 per cent or more tumour cells or less than 50 per cent with intense staining were present. Results: PD-L1 was positive in 25 of 99 (25.3%) cervical carcinoma samples. PD-L1 was positive in 18 of 81 (22%) squamous cell carcinomas, 7 of 16 (43.7%) adenocarcinomas and 0 out of 2 adenosquamous carcinomas. Twenty-nine per cent of patients with positive pelvic nodes expressed PD-L1 positivity. None of the patients with paraaortic node metastasis expressed PD-L1 positivity. No statistically significant associations were found between PD-LI positivity and menopausal status, haemoglobin level, histology, tumour size, FIGO stage, nodal involvement and response to treatment. Conclusions: One out of four patients had evidence of PD-L1 positivity in their cervical cancer. No association was found between PD-L1 expression and various clinicopathological factors and response to treatment. But follow-up studies are needed to observe any effect on disease-free or overall survival. Validation of scoring of PD-L1 expression and uniform reporting is required.