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Wide-bandgap perovskite solar cells (WBG-PSCs) are critical for developing perovskite/silicon tandem solar cells. The defect-rich surface of WBG-PSCs will lead to severe interfacial carrier loss and phase segregation, deteriorating the device’s performance. Herein, we develop a surface reconstruction method by removing the defect-rich crystal surface by nano-polishing and then passivating the newly exposed high-crystallinity surface. This method can refresh the perovskite/electron-transporter interface and release the residual lattice strain, improving the charge collection and inhibiting the ion migration of WBG perovskites. As a result, we can achieve certified efficiencies of 23.67% and 21.70% for opaque and semi-transparent PSCs via a 1.67-eV perovskite absorber. Moreover, we achieve four-terminal perovskite/silicon tandem solar cells with a certified efficiency of 33.10% on an aperture area of one square centimeter. The defect-rich surface of wide-bandgap perovskite solar cells leads to severe interfacial carrier loss and phase segregation. Here, the authors reconstruct the surface through nano-polishing followed by passivation, achieving certified efficiency of 33.1% for perovskite/silicon tandem solar cells.

This paper presents comprehensive research of the advantages and applicability of various concrete carbonation detection methods. Employing a combination of Phenolphthalein indicator (PI), Thermogravimetric analysis (TGA), X-ray phase analysis (XRD), Fourier transform infrared spectroscopy (FTIR), and Quantitative calcium carbonate analysis (CA), a detailed comparison to determine the carbonation depth in the partial carbonation zone of concrete specimens is conducted. Among the quantitative analysis methods, CA measures CaCO 3 content based on chemical reactions, while TGA obtains the concentration distribution of Ca(OH) 2 and CaCO 3 . Among qualitative analysis methods, XRD tested the intensity distribution of Ca(OH) 2 and CaCO 3 , while FTIR traced the characteristic peaks of C-O functional groups in a specific spectral range to determine the depth of carbonation of concrete. Results indicate that the depth of carbonation values measured by CA, TGA, XRDA, and FTIR are 2–3 times higher than those measured by PI. This research may provide valuable insights for the design of carbonation detection in concrete.

HighlightsThree bulky cation chlorides (PMACl, PEACl and NMACl) are used to modify the perovskite surface and form pure-anion 2D (PMA)2PbCl4, mixed-anion 2D (PEA)2Pb(IxCl4-x), and non-2D NMAI passivation layers, respectively.Intermolecular interactions between the bulky cations and the strength of cation-halide hydrogen bonds are critical to forming the three distinct passivation layers.Semi-transparent wide-bandgap perovskite solar cells (WBG-PSCs) with ITO as the back electrode show hysteresis-free PCE of 18.60% and VOC deficit of 0.49 V.Wide-bandgap (WBG) perovskite solar cells suffer from severe non-radiative recombination and exhibit relatively large open-circuit voltage (VOC) deficits, limiting their photovoltaic performance. Here, we address these issues by in-situ forming a well-defined 2D perovskite (PMA)2PbCl4 (phenmethylammonium is referred to as PMA) passivation layer on top of the WBG active layer. The 2D layer with highly pure dimensionality and halide components is realized by intentionally tailoring the side-chain substituent at the aryl ring of the post-treatment reagent. First-principle calculation and single-crystal X-ray diffraction results reveal that weak intermolecular interactions between bulky PMA cations and relatively low cation-halide hydrogen bonding strength are crucial in forming the well-defined 2D phase. The (PMA)2PbCl4 forms improved type-I energy level alignment with the WBG perovskite, reducing the electron recombination at the perovskite/hole-transport-layer interface. Applying this strategy in fabricating semi-transparent WBG perovskite solar cells (indium tin oxide as the back electrode), the VOC deficits can be reduced to 0.49 V, comparable with the reported state-of-the-art WBG perovskite solar cells using metal electrodes. Consequently, we obtain hysteresis-free 18.60%-efficient WBG perovskite solar cells with a high VOC of 1.23 V.

In patients with ST-segment elevation myocardial infarction (STEMI) and multivessel disease (MVD), the treatment strategy for non-infarct-related artery (non-IRA) remains controversial. Quantitative flow ratio (QFR) is a new angiography-based physiological assessment index. However, there is little evidence on the practical clinical application of QFR. Two hundred and twenty-nine patients with STEMI and MVD were recruited for this study. Patients were randomly assigned to either receive QFR-guided complete revascularization (QFR-G-CR) of non-IRA or receive no further invasive treatment. The primary (1°) endpoint analyzed included death due to all causes, non-fatal myocardial infarction (MI), and ischemia-induced revascularization at 12 months post-surgery. Secondary (2°) endpoints included cardiovascular death, unstable angina, stent thrombosis, New York Heart Association (NYHA) class IV heart failure, and stroke at 1 year post surgery. Massive bleeding and contrast-associated acute kidney injury (CAKI) were used as safety endpoints. Around the 12 month follow up, the 1o outcome was recorded in 11/115 patients (9.6%) in the QFR-G-CR population, relative to 23/114 patients (20.1%) in the IRA-only PCI population (hazard ratio [HR]: 0.45; 95% confidence interval [CI]: 0.22-0.92; p = 0.025). Unstable angina in 6 (5.2%) and 16 (14.0%) patients (HR: 0.36; 95% CI: 0.14-0.92; p = 0.026), respectively. No marked alterations were found in the massive bleeding and CAKI categories. In conclusion, STEMI and MVD patients can benefit from QFR-G-CR of non-IRA lesions in the initial stages of acute MI. This can help reduce incidences of major adverse cardiovascular events and unstable angina, relative to IRA treatment only. Chinese Clinical Trial Registration number: ChiCTR2100044120.

Background: Exercise is one of the effective ways to improve cognition. Different forms of exercises have different effects on the improvement of cognitive impairment. In recent years,exergames based on Non-Immersive Virtual Reality(NIVR-Exergames) have gradually been applied to clinical rehabilitation. However, the mechanism of NIVR-Exergames on improving motor cognition has not been clarified. Therefore, the aim of this study is to find whether NIVR-Exergames result in a better neural response mechanism to improve the area of the cerebral cortex related to motor cognition under fNIRS dynamic monitoring in comparison with resistance exercise . Methods: 26 healthy young subjects (18–24 years old) were randomly divided into group A (n = 10) and group B (n = 10) according to a computerized digital table method. Task 1 was an NIVR-Exergame task, and Task 2 was resistance band stretching. Group A first performed Task 1, rested for 30 minutes (i.e., a washout period), and then performed Task 2. Group B had the reverse order. The fNIRS test was synchronized in real time during exercise tasks.The primary outcomes were beta values from the general linear model (GLM) in different regions of interest (ROIs), and the secondary outcomes were heart rate, blood pressure, reaction time of 2-back , and accuracy rate of 2-back . Results: The activation differences of Task 1 and Task 2 in the right premotor cortex (PMC) (P = 0.025) and the left PMC (P = 0.011) were statistically significant. There were statistically significant differences in the activation of the right supplementary motor area (SMA) (P = 0.001) and right PMC (P = 0.001) between baseline and Post-task 1. The differences in systolic pressure (SBP) between the two groups at three time points among women were statistically significant (P1 = 0.009, P2 < 0.001, P3 = 0.044). Conclusions: In this study, we found that NIVR-Exergames combined with motor and challenging cognitive tasks can promote the activation of SMA and PMC in healthy young people compared with resistance exercise alone, providing compelling preliminary evidence of the power for the rehabilitation of motor and cognitive function in patients with central nervous system diseases.

The Poly( N -isopropylacrylamide) (PNIPAm) hydrogel has gained significant interest in the realms of tissue engineering and regenerative medicine due to its biocompatible characteristics and ability to replicate the properties of the natural extracellular matrix (ECM). The given environment possesses three-dimensional attributes that facilitate the proliferation and specialization of cells, making it suitable for the use of tissue engineering applications. The temperature-responsive nature of PNIPAm hydrogel enables it to encapsulate and release therapeutic ingredients in response to temperature fluctuations. This characteristic exhibits potential for the advancement of drug administration systems in regenerative medicine. PNIPAm hydrogel exhibits thermoresponsive properties that make it very suitable for applications in biofabrication techniques, such as 3D printing, and for replicating intricate tissue structures. Moreover, it shows significant potential in stem cell engineering by establishing a favorable setting that promotes cell growth and specialization. The material has the potential to be used as a scaffold for tissue regeneration, allowing its porosity structure and mechanical properties to be customized to meet various tissue needs. Researchers are currently studying the integration of bioactive compounds into PNIPAm hydrogel scaffolds to enhance tissue regeneration and cellular responses. This review provides a comprehensive overview of the uses of PNIPAm in tissue engineering, specifically highlighting its strengths in additive manufacturing.

Background Type-2 diabetes has become a major disease and is known to seriously impair people’s health worldwide. Prediabetes includes impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) and is the most critical period for preventing type-2 diabetes, as it can be identified and reversed. Studies in the past decade have indicated that acupuncture and Chinese herbal medicine may be beneficial for treating prediabetes. However, a randomized controlled trial (RCT) should be conducted to obtain more clinical evidence on this topic. Methods/design An RCT will be implemented in this study, using a72-week study period (24 weeks for the intervention and 48 weeks for follow-up). Participants will be recruited from the Fifth Affiliated Hospital of Guangzhou Medical University in China. Eighty participants will be randomized to the treatment group (acupuncture plus herbal medicine and health education) or the control group (health education only), 40 participants in each. People included in this study must have been diagnosed with prediabetes using Western medicine criteria. The endpoint indices include the incidence of diabetes mellitus and the reversion rate. The primary outcome is fasting plasma glucose (FPG) level, 2-h plasma glucose (2-hPG) level after a 75-g oral glucose tolerance test (OGTT), and glycosylated hemoglobin (HbA 1c ) level. Secondary outcomes include the following: Body Mass Index (BMI); hemorheology, including shear rates of whole-blood viscosity and plasma viscosity. Safety indices include hepatic (ALT, AST) and renal function (BUN, Cr) and records of adverse events, including diarrhoea, colds, pharyngitis, and sleep disorders. Quality control will be implemented, including quality control of the laboratory, researchers, participants, investigational drugs, data and documents, occurrence of bias, supervision, among others, according to uniform standard operating procedures (SOPs) which have been established by the Good Clinical Practice (GCP) office of the Fifth Affiliated Hospital of Guangzhou Medical University. Discussion The aim of this study is to evaluate the efficacy and safety of acupuncture paired with herbal medicine for the treatment of patients with prediabetes. Trial registration Chinese clinical trials register ChiCTR-INR-16008891 . Registered on 23 July 2016.

Semi-transparent perovskite solar cells (ST-PSCs) have broad applications in building integrated photovoltaics. However, the stability of ST-PSCs needs to be improved, especially in n-i-p ST-PSCs since the doped 2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenyl-amine)-9,9′-spirobifluorene (Spiro-OMeTAD) is unstable at elevated temperatures and high humidity. In this work, a π-conjugated polymer poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophene-2-yl)-benzo[1,2-b:4,5-b′]dithiophene))-alt-(5,5-(1′,3′-di-2-thienyl-5′,7′-bis(2-ethylhexyl)benzo[1′,2′-c:4′,5′-c′]dithiophene-4,8-dione)] (PBDB-T) is selected to form a polymer composite hole transport layer (HTL) with Spiro-OMeTAD. The sulfur atom of the thiophene unit and the carbonyl group of the polymer interact with the undercoordinated Pb 2+ at the perovskite surface, which stabilizes the perovskite/HTL interface and passivates the interfacial defects. The incorporation of the polymer also increases the glass transition temperature and the moisture resistance of Spiro-OMeTAD. As a result, we obtain ST-PSCs with a champion efficiency of 13.71% and an average visible light transmittance of 36.04%. Therefore, a high light utilization efficiency of 4.94% can be obtained. Moreover, the encapsulated device can maintain 84% of the initial efficiency after 751 h under continuous one-sun illumination (at 30% relative humidity) at the open circuit and the unencapsulated device can maintain 80% of the initial efficiency after maximum power tracking for more than 1250 h under continuous one-sun illumination.

The geopolymerization of aluminosilicate materials in alkaline environments is a complex physicochemical process that greatly influences the microstructure and engineering performances. This work aims to reveal the geopolymerization process of metakaolin-based geopolymer (MKG) in the first 5 d. Physicochemical characteristics of different evolution stages are disposed of in chronological order. The evolutions of electrical resistivity, dehydration process, volume deformation, and ionic concentration are comprehensively analyzed. Results show that chemical dissolution produces large dismantled fragments rather than small free monomers. The formation of a solid matrix follows the “spatial filling rule”, which means that gels grow by locking swelling fragments to form a framework, then densely filling residual space. Based on chemical models, early geopolymerization of MKG can be divided into six stages from the physicochemical perspective as dismantling, locking fixation, free filling, limited filling, second dissolution, and local mending. Those findings expand the understanding of the phase evolution of the early geopolymerization process; thus, the microstructure of MKG can be better manipulated, and its engineering performances can be improved.