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The recent tremendous progress in monolithic perovskite-based double-junction solar cells is just the start of a new era of ultra-high-efficiency multi-junction photovoltaics. We report on triple-junction perovskite-perovskite-silicon solar cells with a record power conversion efficiency of 24.4%. Optimizing the light management of each perovskite sub-cell (∼1.84 and ∼1.52 eV for top and middle cells, respectively), we maximize the current generation up to 11.6 mA cm -2 . Key to this achievement was our development of a high-performance middle perovskite sub-cell, employing a stable pure-α-phase high-quality formamidinium lead iodide perovskite thin film (free of wrinkles, cracks, and pinholes). This enables a high open-circuit voltage of 2.84 V in a triple junction. Non-encapsulated triple-junction devices retain up to 96.6% of their initial efficiency if stored in the dark at 85 °C for 1081 h., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Monolithic two-terminal (2T) perovskite/CuInSe 2 (CIS) tandem solar cells (TSCs) combine the promise of an efficient tandem photovoltaic (PV) technology with the simplicity of an all-thin-film device architecture that is compatible with flexible and lightweight PV. In this work, we present the first-ever 2T perovskite/CIS TSC with a power conversion efficiency (PCE) approaching 25% (23.5% certified, area 0.5 cm 2 ). The relatively planar surface profile and narrow band gap (∼1.03 eV) of our CIS bottom cell allow us to exploit the optoelectronic properties and photostability of a low-Br-containing perovskite top cell as revealed by advanced characterization techniques. Current matching was attained by proper tuning of the thickness and bandgap of the perovskite, along with the optimization of an antireflective coating for improved light in-coupling. Our study sets the baseline for fabricating efficient perovskite/CIS TSCs, paving the way for future developments that might push the efficiencies to over 30%., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Recent advances in solution processing of micrometer-thick perovskite solar cells over textured silicon bottom solar cells allowed a new promising approach for the fabrication of 2T perovskite/silicon tandem photovoltaics, combining optimal light management in the textured bottom cell with the ease of solution processing. Detailed simulations are needed to assess the performances of this morphology configuration (thick perovskite configuration). In this work, in-depth optical and energy yield (EY) simulations are performed to compare the thick perovskite configuration with other relevant morphology configurations for 2T perovskite/silicon tandem photovoltaics. Under standard test conditions, the total photogenerated current of the thick perovskite configuration is 1.3 mA cm -2 lower (-3.4% relative) than the one of the conformal perovskite on textured silicon configuration for non-encapsulated cells and only 0.8 mA cm -2 (-2.1% relative) for encapsulated cells. Under realistic outdoor conditions, EY modelling for a wide range of locations shows that, while conformal perovskite on textured silicon configuration remains the optimal configuration, thick perovskite configuration exhibits a mere ∼2.5% lower annual EY. Finally, intermediate scenarios are investigated with the angle of the perovskite front-side texture differing from the silicon texture and critical angles for efficient light management in these configurations are identified.

Markers of viral replication are fundamental tools for understanding the mode of transmission, diagnosis and management of hepatitis C virus (HCV) infection. A new enzyme-linked immunosorbent assay for quantitative detection of free and complexed HCV core antigen (HCV Ag) has been developed. The aim of this study is to evaluate the clinical performance of the new test and compare it with the most widely used commercially available RT-PCR-based assay. To determine the cut-off value we tested 60 samples from anti-HCV negative samples and selected a qualitative cut-off value of 3 pg/ml. To evaluate the usefulness of the new assay in confirming serologically indeterminate results we collected 62 sera. To evaluate the HCV Ag and HCV-RNA relationship we tested 245 samples from patients with different clinical conditions. The results of 61 out of 62 (98.4%) anti-HCV indeterminate samples were found to agree, whereas only one serum was found to be RT-PCR positive and HCV Ag negative. We also found the results to agree in 77.6% (190/245) of the samples from infected patients, while we observed higher agreement in untreated patients, both with and without evidence of liver damage. The correlation coefficient (r) observed between HCV Ag and HCV-RNA was 0.88. The regression line meets the cut-off value at an HCV-RNA concentration of approximately 40,000 IU/ml. In conclusion, we found that the results from the total HCV Ag test agree with the RT-PCR results and therefore we believe that this test could become a useful tool for the diagnosis and management of HCV infection.

Hepatitis C virus (HCV) infection remains a major problem in haemodialysis units despite the risk decrease provided by anti-HCV screening of blood. The exact mode of transmission of HCV in the dialysis units remains unclear. To identify the route of the virus and the mechanisms of transmission an investigation into the outbreak of HCV infection in a haemodialysis unit on a molecular level was held: 12 newly infected patients and 14 already infected were investigated by sequencing the 5' untranslated region of the viral genome. The results showed that 3 strains infected new cases and these strains matched those sequenced in already infected patients. Transmission occurred between patients treated on the same shift and also between different rooms. Console and blood or blood product contamination was excluded. Our study gave molecular evidence of patient-to-patient transmission of HCV in a haemodialysis unit. Our data underline the importance of the strict enforcement of standard precautions to prevent HCV transmission and failure of the isolation of anti-HCV positive patients as preventive measure.

An account is given of methods used in the detection of HBs antigen in the serum of blood donors. It is felt that the microelisa (microenzyme-linked immunosorbent assay) method is the most sensitive, leaving aside the RIA. Its easy execution and low cost make it a sound alternative to the more sensitive, yet more complex RIA.

Total transfusion practice in hospitals is examined and reference is made to the methods regarded as indispensable in avoiding damage to the newborn.

The results of a study showing correlations between the behaviour of complement serum level, the presence of antigen Au, variations in serum immunoglobulin and the behaviour of transaminases in the cases of hepatitis examined are reported. It was found that the reduction in complement level during the initial stage of the disease coincides directly with antigenaemia positivity, increased IgM production, large increases in transaminase activity and inversion of the SGOT/SGPT ratio.

The differential diagnosis of type A and B viral hepatitis is discussed and guidelines for the prevention of post-transfusional hospital hepatitis are proposed. Methods for the immunological demonstration of HBs antigen are illustrated, together with the respective positivity percentages in blood donors.

The usefulness of determining G.O. and G.P. transaminase is examined and techniques described. Such studies take on particular importance for the selection of particular importance for the selection of donors, some with preclinical viral hepatitis.

Reference is made to the indications for platelet transfusions, the way in which they are prepared, and the criteria used in assessment of their therapeutic results.

A serological analysis of alpha and beta agglutinin titres has been carried out in cancer patients. Statistics of the patients' blood groups were also taken. The study showed an increased agglutinin titre, the expression of the functioning of the organism's defensive powers. Only in the terminal stage of the neoplastic disease were antibody titres low, the sign of low antibody reactivity of the affected organism.

Following a description of factor Du, a variant of factor D, a personal series of about 3% is described and the technique using indirect Coombs test is indicated. Identification of factor Du takes on importance in the prophylaxis of post-transfusional isoimmunization as donors of Rh negative blood with Du positive must be considered Rh positive donors.