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A high-quality Sn-based perovskite absorption layer and effective carrier transport are the basis for high-performance Sn-based perovskite solar cells. The suppression of Sn2+ oxidation and rapid crystallization is the key to obtaining high-quality Sn-based perovskite film. And interface engineering is an effective strategy to enhance carrier extraction and transport. In this work, tin fluoride (SnF2) was introduced to the perovskite precursor solution, which can effectively modulate the crystallization and morphology of Sn-based perovskite layer. Furthermore, the hole-transporting layer of PEDOT:PSS was modified with CsI to enhance the hole extraction and transport. As a result, the fabricated inverted Sn-based perovskite solar cells demonstrated a power conversion efficiency of 7.53% with enhanced stability. [ABSTRACT FROM AUTHOR]

[Display omitted] The efficiency and durability of perovskite solar cells (PSCs) are closely related to the property and stability of each functional layer involved in device. Owing to the excellent hole transport properties, the additive-doped Spiro-OMeTAD (2,2′,7,7′-tetrakis (N, N -di-p-methoxyphenylamine) 9,9′-spirobifluorene) has become an excellent hole-transporting material for obtaining highly efficient PSCs. However, the hygroscopic nature of additives and the pinholes caused by poor film-forming capability inevitably impair the performance and long-term stability of Spiro-OMeTAD and the resulting PSCs. In this study, the hydrophobic polymer polystyrene (PS) was incorporated to improve the hydrophobicity and film-forming capability of the additive-doped Spiro-OMeTAD films. Based on the PS-modified Spiro-OMeTAD and carbon electrodes, the derived planar carbon-based PSCs exhibited significantly enhanced long-term stability, which can maintain 92% of its initial efficiency after aging for 2500 h under ambient atmosphere without encapsulation. In addition, the PS-modified Spiro-OMeTAD exhibited improved morphology with reduced pinholes, contributing to significantly enhanced interfacial carrier transport. Finally, a champion power conversion efficiency of 21.06% was obtained, which is one of the highest efficiencies reported for the planar carbon-based PSCs to date. [ABSTRACT FROM AUTHOR]

Sternal wound infection (SWI) is the most common complication of the median sternal incision. The treatment time is long, and the reconstruction is difficult, which causes challenges for surgeons. Plastic surgeons were often involved too late in such clinical scenarios when previous empirical treatments failed and the wound damage was relatively serious. Accurate diagnosis and risk factors against sternal wound infection need to be in focus. Classification of different types of sternotomy complications post-cardiac surgery is important for specific categorization and management. Not familiar with this kind of special and complex wound, objectively increasing the difficulty of wound reconstruction. The purpose of this comprehensive review is to review the literature, introduce various SWI risk factors related to wound nonunion, various classification characteristics, advantages and disadvantages of various wound reconstruction strategies, to help clinicians understand the pathophysiological characteristics of the disease and choose a better treatment method. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the scientific productivity of China's science system. This paper employs the Malmquist productivity index (MPI) based on Data Envelopment Analysis (DEA). The results reveal that the overall efficiency of Chinese universities increased significantly from 2009 to 2016, which is mainly driven by technological progress. From the perspective of the functions of higher education, research and transfer activities perform better than the teaching activities. As an implication, the indicator selection mechanism, investigation period and the MPI model can be further extended in the future research. The results indicate that Chinese education administrative departments should take actions to guide and promote the teaching activities and formulate reasonable resource allocation regulations to reach the balanced development in Chinese universities. This paper selects 58 Chinese universities and conducts a quantified measurement during the period 2009–2016. Three main functional activities of universities (i.e. teaching, researching, and application) are innovatively categorized into different schemes, and we calculate their performance, respectively. [ABSTRACT FROM AUTHOR]

Highlights • Extensively evaluate pixel-level image fusion based on CNN pedestrian detectors. • Study effective methods to combine pixel-level fusion and CNN-fusion architectures. • Three state-of-the-art CNN-based object detectors are evaluated. Abstract Vision-based pedestrian detection that can last all day is crucial in advanced driver-assistance systems (ADAS), autonomous vehicles and video surveillance. Based on the fact that the wavelength of human body radiation falls around 9.3 μm, thermal images have distinctive advantages for pedestrian detection in the nighttime. With the recent success of convolutional neural networks (CNNs) in the vision community, how to properly explore information in color and thermal images using CNNs-based methods attracts the attention of researchers. Previous CNN-based multispectral pedestrian detectors focus on the design of network architectures. The main contributions of this paper are as follows. First, pixel-level image fusion are also extensively evaluated based on a state-of-the-art CNNs-based framework in the daytime and nighttime for pedestrian detection. Second, the effective strategies to combine pixel-level fusion methods and CNN-fusion architectures are studied based on extensive experimental results. Two combination strategies are designed and an exhaustive experimental analysis is performed to evaluate different combinations for all-day pedestrian detection. Extensive results based on a multispectral pedestrian benchmark show that some pixel-level image fusion methods can achieve similar or even better performance than CNN-fusion architectures, which emphasizes the importance of pixel-level fusion in CNN-based pedestrian detectors. The combination of both can usually more properly exploit multispectral information and further boost detection performance. [ABSTRACT FROM AUTHOR]

Coilin is a marker protein of the Cajal body (CB). Cajal bodies, functional nuclear structure, play important roles for the maturation of telomerase mRNAs. However, whether CB participates in the process of cell senescence is unknown. Cisplatin is a frequently used drug for the chemotherapy for various cancers, which was recently reported to be able to induce premature senescence of tumor cells. In this study, we found that when HeLa cells were treated with 2 μg/ml cisplatin for 4 days, stagnant cell growth, especially in cells stained positive of SA-β-gal, was accompanied with significant changes in CB morphologies. The removal of cisplatin allowed the recovery of normal CB appearance, but was not able to restore cells from senescent states. Knocking down coilin expression by siRNA attenuated the growth and reduced the viability of treated cells, and the decreased rate of CB formation correlated with increased staining of SA-β-gal. Interestingly, when coilin knocked-down cells exposed to cisplatin, the drug sensitivity as shown by the reduction of cell viability was significantly increased compared to the control siRNA transfection groups. Overexpression of coilin phosphomutants increased SA-β-gal fluorescence following treatments with cisplatin as compared to the wild type coilin transfection. Our results indicated that coilin was an important functional player that involved in cisplatin-induced premature cell senescence. It suggested that the modulation of coilin expression could be considered as a potential anti-tumor strategy to increase the sensitivity of chemotherapy through which drug-induced cell senescence was accelerated. [ABSTRACT FROM AUTHOR]

The zeolitic imidazolate framework (ZIF−8)@polyacrylonitrile (PAN) nanofiber membrane was prepared and carbonized for heavy metal cadmium ion (Cd2+) adsorption in aqueous medium. Zinc oxide (ZnO) was first sputtered onto the surface of the PAN electrospun nanofiber membrane to provide a metal ion source. Then, the ZIF−8@PAN nanofiber membrane was prepared via in situ solvothermal reaction and carbonized in a tube furnace at 900 °C under a N2 atmosphere to enhance adsorption performance. The synthesized ZIF−8 particles with polyhedral structure were uniformly immobilized on the surface of the PAN electrospun nanofiber membrane. After being heated at 900 °C, the polygonal ZIF−8 shrank, and the carbonized ZIF−8@PAN nanofiber membrane was obtained. Compared with the nanofiber membrane without being carbonized, the adsorption capacity of the carbonized ZIF−8@PAN nanofiber membrane reached 102 mg L−1, and its Cd2+ adsorption efficiency could be more than 90% under the adsorption temperature of 35 °C and solution of pH = 7.5 conditions. According to the adsorption thermodynamics analysis, the Cd2+ adsorption process of the carbonized ZIF−8@PAN nanofiber membrane was spontaneous. The whole Cd2+ adsorption process was more suitably described by the pseudo second-order adsorption kinetics model, indicating that there exists a chemical adsorption mechanism besides physical adsorption. [ABSTRACT FROM AUTHOR]

Objective: The high levels of oxidative stress and apoptosis of pancreatic islet cells after severe burns lead to the dysfunction of islets and glucose metabolism disorders. Silent information regulator of transcription 1 (SIRT1) can decrease oxidative stress and apoptosis of islets in diabetes mellitus. This study aimed to investigate the role of SIRT1 on pancreatic islets and whether nicotinamide mononucleotide (NMN) can impact the function of pancreatic islets after severe burns.Methods: A 30% total body surface area full-thickness burn model was established using male C57BL/6 mice, and mice were randomized into sham group, burn group, burn + NMN group and burn + NMN + EX-527 group. The concentration of nicotinamide adenine dinucleotide (NAD), the expression of SIRT1, apoptosis induction, mitochondrial function and related signalling pathways of pancreatic islets at 24 h after severe burns were tested.Results: Severe burns led to decreased NAD level and SIRT1 expression of pancreatic islets, increased apoptosis rate, and mitochondrial dysfunction of pancreatic islets. NAD repletion by NMN and upregulation of SIRT1 expression reduced the phosphorylation and acetylation levels of NF-κB p65 and burn-induced apoptosis. Meanwhile, the mitochondrial function of islets was rescued by NMN treatment through the SIRT1/UCP2 axis and SIRT1/PGC1-α axis. In addition, the fasting blood glucose decreased and glucose-stimulated insulin secretion was improved with NMN treatment after severe burns. This protective effect of NMN could be abolished by EX-527, the inhibitor of SIRT1.Conclusion: NMN can increase the concentration of NAD+ of pancreatic islets and regulate SIRT1 and its downstream targets, thereby reducing apoptosis, maintaining mitochondrial function and improving pancreatic islet function after severe burn injury. [ABSTRACT FROM AUTHOR]

This paper attempts to examine whether the environmental Kuznets curve (EKC) hypothesis is supported in MENA countries. We use, a novel RAM (range-adjusted measure)-based global Malmquist-Luenberger productivity index, accounting for slacks of inputs as well as desirable and undesirable outputs, to evaluate and decompose "green" productivity growth rates into technical change, pure efficiency change and scale change. By employing a panel smooth transition regression (PSTR) model, we investigate the income elasticity of environmental performance with respect to the decomposition factors. Our empirical results show that there are double thresholds when technical change and scale change are taken as transition variables, then leading to an inverted N-shaped curve between income and environmental performance. A single threshold is found when pure efficiency change is considered as a transition variable, yielding to an inverted U-shaped curve. Thus, our research does not find support for the EKC hypothesis. [ABSTRACT FROM AUTHOR]

A new acceptor-donor-acceptor (A-D-A) type small molecular donor named as DRTB-CT was designed and synthesized by replacing the fluorine atoms of DRTB-FT with chlorine atoms. Such a small change plays an important role in inhibiting the strong molecular crystallinity and excessive self-aggregation in donor phase due to the larger radius of chlorine atom, which leads to optimized morphology of the active layer. Based on the same nonfullerene acceptor (F–2Cl), the optimal device of DRTB-CT exhibits a higher power conversion efficiency (PCE) of 9.05% compared with that of the fluorinated molecule (7.66%), benefiting from the increased fill factor (FF, 0.568) and short-circuit current density (J sc , 15.07 mA cm−2). The results indicate that the introduction of chlorine atoms is an effective strategy in developing new small molecular donors with high device performances. [Display omitted] • A new small molecular donor named DRTB-CT with two chlorinated side chains was synthesized. • DRTB-CT exhibits better photoelectric properties compared with fluorinated counterpart. • The steric effect of large radius prevents the excessive self-aggregation in donor phases. • DRTB-CT based all-small-molecule organic solar cells gave a high PCE of 9.05%. • Introduction of chlorine atoms is favorable for designing new materials with high performances. [ABSTRACT FROM AUTHOR]