Metal halide perovskite solar cells (PSCs), with their exceptional properties, show promise as photoelectric converters. However, defects in the perovskite layer, particularly at the grain boundaries (GBs), seriously restrict the performance and stability of PSCs. Now, a simple post‐treatment procedure involves applying 2‐aminoterephthalic acid to the perovskite to produce efficient and stable PSCs. By optimizing the post‐treatment conditions, we created a device that achieved a remarkable power conversion efficiency (PCE) of 21.09 % and demonstrated improved stability. This improvement was attributed to the fact that the 2‐aminoterephthalic acid acted as a cross‐linking agent that inhibited the migration of ions and passivated the trap states at GBs. These findings provide a potential strategy for designing efficient and stable PSCs regarding the aspects of defect passivation and crystal growth.

Lead-free tin-based perovskites have attracted widespread research interest due to their nontoxicity and potential commercialization. However, their practical application is limited by high density of intrinsic defects and easy oxidation of Sn 2+ in ambient environment. To address these issues, we demonstrate an environment-friendly stable broadband photodetector based on CsSnI 3 perovskite with conventional SnF 2 and reducing agent ascorbic acid additive.Through optimizing the concentration of ascorbic acid, the optimal device reveals high responsivity (0.257 A W −1 ), fast response speed (0.35/1.6 ms), and excellent stability. The properties are comparable to most previously reported lead-free perovskite photodetectors. The enhanced performance is mainly due to the fact that ascorbic acid promotes the crystal growth, suppresses the formation of Sn 4+ , and makes it have good semiconductivity rather than metallicity.

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Patients with diabetes often experience multiple disease complications. Hypoglycemic agents can have both positive and negative effects on diabetic complications, which should be carefully assessed when personalized treatment strategies are developed. In this study we report that dipeptidyl peptidase 4 inhibitors (DPP-4is), a group of widely used antihyperglycemic agents, can improve diabetic wound healing, independent of their beneficial effects on glycemic control. In particular, DPP-4is promoted the migration and epithelial-mesenchymal transition of keratinocytes, directly and indirectly, by inducing stromal cell-derived factor 1α production of fibroblasts in vitro and in diabetic mice. In addition, DPP-4is attenuated collagen synthesis and deposition, which may diminish scar formation. Furthermore, the results of a randomized clinical trial (NCT02742233) involving 67 patients with type 2 diabetes supported the role of DPP-4i treatment in diabetic wound healing. Our findings support the application of DPP-4i as a preferred option for treating ulcers in patients with diabetes.

Construction of C–C bonds via alkoxy radical-mediated remote C(sp3)–H functionalization is largely unexplored, as it is a formidable challenge to directly generate alkoxy radicals from alcohols due to the high bond dissociation energy (BDE) of O–H bonds. Disclosed herein is a practical and elusive metal-free alcohol-directed heteroarylation of remote unactivated C(sp3)–H bonds. Phenyliodine bis(trifluoroacetate) (PIFA) is used as the only reagent to enable the coupling of alcohols and heteroaryls. Alkoxy radicals are readily generated from free alcohols under the irradiation of visible light, which trigger the regioselective hydrogen-atom transfer (HAT). A wide range of functional groups are compatible with the mild reaction conditions. Two unactivated C–H bonds are cleaved and one new C–C bond is constructed during the reaction. This protocol provides an efficient strategy for the late-stage functionalization of alcohols and heteroaryls.

Background/Aims: Geriatric nutritional risk index (GNRI) was developed as a “nutrition-related” risk index and was reported in different populations as associated with the risk of all-cause and cardiovascular morbidity and mortality. Therefore, GNRI can be used to classify patients according to a risk of complications in relation to conditions associated with protein-energy wasting (PEW). However, not all reports pointed to the prognostic ability of the GNRI. The purpose of this study was to assess the associations of GNRI with mortality in chronic hemodialysis patients. Methods: We electronically searched original articles published in peer-reviewed journals from their inception to September 2018 in The PubMed, Embase, and the Cochrane Library databases. The primary outcome was all-cause and cardiovascular mortality. We pooled unadjusted and adjusted odds ratios (ORs) with 95% confidence intervals (95% CIs) using Review Manager 5.3 software. Results: A total of 10,739 patients from 19 cohort studies published from 2010 to 2018 were included. A significant negative association was found between the GNRI and all-cause mortality in patients with chronic hemodialysis (OR, 0.90; 95% CI, 0.84-0.97, p=0.004) (per unit increase) and (OR, 2.15; 95% CI, 1.88-2.46, p＜0.00001) (low vs. high GNRI). Moreover, there was also a significant negative association between the GNRI (per unit increase) and cardiovascular events (OR, 0.98; 95% CI, 0.97-1.00, p=0.01), as well as cardiovascular mortality (OR, 0.89; 95% CI, 0.80-0.99, p=0.03). Conclusion: Our findings supported the hypothesis that the low GNRI is associated with an increased risk of all-cause and cardiovascular mortality in chronic hemodialysis patients. Based on our literature review, GNRI has been found to be an effective tool for identifying patients with nutrition-related risk of all-cause and cardiovascular disease.

Thanks to the tunable bandgap and excellent photoelectric characteristics, perovskites have been widely used in semitransparent solar cells (ST‐SCs). Most works present unsatisfactory power conversion efficiencies (PCEs) through reducing the thickness of the perovskite films because there is a trade‐off between PCE and average visible transmittance (AVT). As a consequence, most PCEs are less than 12% when the AVT is higher than 20% due to the limited voltage (Voc) and short‐circuit current (Jsc). Herein, a strategy of intermediate adduct (IMAT) engineering is developed to improve the film quality of the inorganic perovskite CsPbI2Br, which is a challenging issue to limit its performance of efficiency and stability. A normal n–i–p‐structured PSC based on the optimal CsPbI2Br film delivers a PCE of 16.02% with excellent stability. Furthermore, through optimizing the electrode type and interface, the ST‐PSC shows a high Voc larger than 1.2 V and the PCE reaches 14.01% and 10.36% under an AVT of 31.7% and 40.9%, respectively. This is the first demonstration of a CsPbI2Br ST‐PSC, and it outperforms most of other types of perovskites.

Cesium lead mixed‐halide perovskite (CsPbIBr2), as one of the all‐inorganic perovskites, has attracted great attention owing to its great ambient stability and suitable bandgap. Unfortunately, due to its low film coverage, high density of defects and unfavorable band energy level, the CsPbIBr2 based solar cells suffer from low efficiency. In this work, the Lewis base poly(ethylene glycol) (PEG) is adopted as additive to modify the pure CsPbIBr2. By optimizing the molecular weight and dosage of PEG, the resultant PEG:CsPbIBr2 film possesses suppressed non‐radiative electron–hole recombination, a favorable energy band structure and a weaker sensitive to the moisture. As a result, the device based on the PEG:CsPbIBr2 yields a champion power conversion efficiency (PCE) of 11.10%, with a open‐circuit voltage of 1.21 V, a short‐circuit current of 12.25 mA cm−2, and a fill factor of 74.82%, which is 44.3% higher than its counterpart without PEG. Moreover, the PEG modified device shows excellent long‐term stability, retaining over 90% of the initial efficiency after 600 h storage in ambient condition without encapsulation. In comparison, the device without PEG shows an inferior stability with PCE sharply dropping to 0% within 50 h.