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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]

Metal clusters often exhibit superior chemical, electronic, and geometrical properties and can show exciting catalytic performance. The catalytic behaviour of the clusters is strongly affected by their size and composition, offering unique opportunities to fine-tune such materials for a specific application. In this study, atomically precise [Au6(dppp)4](NO3)2, [Au9(PPh3)8](NO3)3, [Au13(dppe)5Cl2]Cl3 and Au101(PPPh3)21Cl5 clusters were synthesised, characterised and their activity for electrocatalytic CO2 reduction is compared. These Au clusters were deposited onto carbon paper to serve as the cathode for the electrochemical reduction of CO2. The experimental studies suggest that the clusters remain intact upon deposition on the carbon paper but undergo agglomeration during CO2 electrolysis. The cluster-based catalysts demonstrated high selectivity (75%—90%) for CO production over hydrogen evolution reaction. Upon calcination, the activity of the cluster-based electrodes decreases, which can be attributed to the agglomeration of small clusters into larger bulk-like nanoparticles, as suggested by XPS, XAS and SEM. A series of phosphine-protected gold clusters supported on carbon paper were studied as CO2RR electrocatalysts. The CO2RR activity was dependent on their size and ligand density. Thermal annealing of the catalysts invariably lowered CO selectivity due to agglomeration of the clusters into larger nanoparticles. [ABSTRACT FROM AUTHOR]

The structural determination of ultrasmall clusters remains a challenge due to difficulties in crystallisation. Often the atomically precise clusters undergo structural change under the influence of the environment. X-ray absorption spectroscopy (XAS) can be an attractive tool to study the electronic and geometric properties of such clusters deposited onto various supports under in situ conditions. Herein, [Au6(dppp)4](NO3)2, [Au9(PPh3)8](NO3)3, [Au13(dppe)5Cl2]Cl3, and Au101(PPPh3)21Cl5 clusters were studied using XAS. The clusters exhibited distinct features compared to bulk gold. XANES results show a systematic increase in the absorption edge energy and white line intensity, with a decrease in cluster nuclearity. The EXAFS of clusters are sensitive to nuclearity and ligands and were fitted with their known crystal structures. This study advances the understanding of the phosphine-ligated metal clusters relevant to practical applications in catalysis and sensing. [ABSTRACT FROM AUTHOR]