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An isolated interleaved boost converter (IIBC) based single-phase grid-interfaced photovoltaic system (SPGIPS) and its control are proposed in this article. The proposed double-stage SPGIPS consists of an IIBC and a single-phase full bridge voltage source converter (SPFBVSC). An IIBC is designed using a high-frequency transformer (HFT), two primary inductors, and two static switches with its emitter shared with photovoltaic (PV) panel ground. Shared emitter terminal reduces the gate control circuit complexity and HFT facilitates a galvanic isolation between PV panels and the utility grid, and thus it mitigates the appearance of leakage current. An IIBC reduces the ripple in PV panel current and voltages and therefore guarantees improved maximum power point operation (MPPO) of the PV system. To ensure the MPPO at PV panel terminals, a sliding mode control is used. The output DC terminals of IIBC are interfaced with self-commutated switches based SPFBVSC. To synchronize SPFBVSC with the utility grid, a new modified fourth-order generalized integrator (mFOGI) is developed. The mFOGI provides stable synchronization signal even under presence of noise, under/over shoot, or DC offset in the AC supply voltage. The proposed SPGIPS control and its performance are validated on Simulink and prototype system. [ABSTRACT FROM AUTHOR]

Background. Spindle cell/sclerosing rhabdomyosarcoma is a rare neoplasm and has an aggressive clinical course. Because of its rarity, we performed a multi-institutional collaboration to comprehend the overarching clinical, histopathological, and immunohistochemical characteristics of a cohort of spindle cell/sclerosing rhabdomyosarcoma. Materials and Methods. Forty-five patients with spindle cell/sclerosing rhabdomyosarcoma were identified. Demographics, clinical, histopathological, and immunohistochemistry data were reviewed and recorded. Results. The patients' age ranged from 1 to 85 years with a male to female ratio of 1.2:1. There were 15 children/adolescents and 30 adults. Eighteen (40%) tumors were located in the head and neck region. Twenty-four (53%) tumors displayed a bimorphic cellular arrangement with hypercellular areas having short, long, and sweeping fascicular and herringbone pattern, and hypocellular areas with stromal sclerosis and associated hyalinized and/or chondromyxoid matrix. Histomorphological differentials considered were leiomyosarcoma, malignant peripheral nerve sheath tumor, fibrosarcoma, nodular fasciitis, liposarcoma, synovial sarcoma, sarcomatoid carcinoma, solitary fibrous tumor, dermatofibrosarcoma protuberans, and schwannoma. Six tumors exhibited marked stromal sclerosis. The myogenic nature was confirmed by immunohistochemistry. Positivity for at least one skeletal muscle-associated marker (MyoD1 and/or myogenin) was observed. Conclusion. Spindle cell/sclerosing rhabdomyosarcoma diagnosis can be challenging as a number of malignant spindle cell neoplasm mimic this entity. Thus a correct diagnosis requires immunohistochemical work up with a broad panel of antibodies. In view of rarity of this neoplasm, further studies on a large cohort of patients with clinical follow-up data are needed for a better understanding of this tumor. [ABSTRACT FROM AUTHOR]

A study was undertaken to analyse farmers' access to various agricultural extension service sources, their preferences and to delineate underlying determinants for their access. The study used NSSO 77th survey dataset of 14,782 households of IGP states (Bihar, Haryana, Punjab, Uttar Pradesh, West Bengal). Farmers' preferences varied, with private agencies--particularly input dealers-- emerging as the top choice, followed by traditional mass media channels and the public extension system. Utility of Cooperative model, and farmer-based organizations have not yet been fully explored for information needs. The inputs (seeds, fertilizers, plant protection) were the most sought-after information. However, in an era of changing needs, farmers should strive to acquire additional information on aspects such as marketing, climate change, and post-harvest functions. The type of information sought by the farmers, influences their preferred sources of extension services. Irrespective of the source, the degree of access diminishes with the decreasing landholding. Among the five IGP states, Haryana emerged as the champion of information access for farmers, while Bihar lagged. Multivariate probit analysis reported that the likelihood of access to agricultural information sources was positively influenced by age, gender, education, size of operational landholding, irrigated area, and sale of produce at MSP. The study suggests making the extension services for small and socio-economically marginalized farmers more inclusive. Inclusiveness of extension services is essential for sustainability because it ensures that all farmers, regardless of their landholding, gender, age, caste, etc., have access to knowledge and resources they need to adopt improved agricultural practices and thus, secure prosperous livelihoods. [ABSTRACT FROM AUTHOR]

Objectives Penile squamous cell carcinomas (PCs) are rare malignancies with a dismal prognosis in a metastatic setting; therefore, novel immunotherapeutic modalities are an unmet need. One such modality is the immune checkpoint molecule programmed cell death ligand 1 (PD-L1). We sought to analyze PD-L1 expression and its correlation with various clinicopathologic parameters in a contemporary cohort of 134 patients with PC. Methods A cohort of 134 patients with PC was studied for PD-L1 immunohistochemistry. The PD-L1 expression was evaluated using a combined proportion score with a cutoff of 1 or higher to define positivity. The results were correlated with various clinicopathologic parameters. Results Overall, 77 (57%) patients had positive PD-L1 expression. Significantly high PD-L1 expression was observed in high-grade tumors (P =.006). We found that 37% of human papillomavirus (HPV)–associated subtypes and 73% of other histotype tumors expressed PD-L1, while 63% of HPV-associated tumors and 27% of other histotype tumors did not (odds ratio, 1.35; P =.002 when compared for HPV-associated groups vs all others). Similarly, PD-L1–positive tumors had a 3.61-times higher chance of being node positive than PD-L1–negative tumors (P =.0009). In addition, PD-L1 high–positive tumors had a 5-times higher chance of being p16ink4a negative than PD-L1 low–positive tumors (P =.004). The PD-L1–positive tumors had a lower overall survival and cancer-specific survival than PD-L1–negative tumors. Conclusions Overall, PD-L1 expression is associated with high-grade and metastatic tumors. Lower PD-L1 expression is observed more frequently in HPV-associated (warty or basaloid) subtypes than in other, predominantly HPV-independent types. As a result, PD-L1 positivity, including higher expression, portends lower overall and cancer-specific survival. These data provide a rational for further investigating PD-L1–based immunotherapeutics in PC. [ABSTRACT FROM AUTHOR]

This paper presents a fifth-order generalized integrator (FOGI) as an orthogonal signal generator (OSG) to obtain a grid synchronization signal for a double-stage single-phase grid-interfaced photovoltaic supply system (GIPVSS). The proposed GIPVSS consists of a single-ended primary inductor converter (SEPIC) and a H-bridge voltage source converter (HBVSC) to transfer solar power to the grid system. The SEPIC controls maximum power delivery (MPD) from the Photovoltaic (PV) array and feeds that power to the grid via an HBVSC. In this study, all energy storage elements (inductors and capacitors) of SEPIC are considered with their effective series resistance (ESR). The dynamic modeling of SEPIC is obtained using a small signal analysis. The control of VSC allows harmonics' mitigation and power factor improvements. A FOGI and a second-order adaptive filtering approach are used in controling VSC. The FOGI is used to obtain a grid synchronization signal from sensed grid voltage under disturbances. The second-order adaptive filtering approach is used to obtain an active load current component. The comparative analysis of FOGI with other reported algorithms is carried out under harmonics in sensed grid voltage. The effectiveness of the proposed system and its control is validated in a laboratory prototype using a Launch Pad TMS320F28379D digital signal processor (DSP). [ABSTRACT FROM AUTHOR]