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Asymmetric‐type UV photodetectors have attracted extensive interest for their applications in modern optoelectronics. Conventional fabrication approaches for asymmetric metal contacts typically cause damage at the metal‐semiconductor interface, leading to Fermi level pinning and further limiting barrier height adjustability and functionality. Herein, for the first time, van der Waals (vdW) asymmetric metal contact on wide bandgap semiconductor gallium‐nitride (GaN) is successfully fabricated and achieve the mitigation of Fermi level pinning effect through the formation of a damage‐free metal‐semiconductor interface. Scanning transmission electron microscopy reveals an atomically clean and sharp interface with a distinct vdW gap between the semiconductor and metal electrode. More importantly, the absence of interface damage effectively suppresses charge recombination and results in substantial enhancement in photoresponse characteristics, demonstrating an increased responsivity from 1.8 to 56.7 A W−1 along with a significantly improved response/recovery time from 545/115 to 420/20 ms and an ultralow dark current at the picoampere‐level compared to that of the photodetector with electrodes fabricated with traditional e‐beam evaporated technique. Such simultaneously enhanced responsivity and response speed overcome the responsivity‐speed trade‐off in asymmetric photodetectors and mark a milestone in integrating asymmetric metal contacts with semiconductors through a non‐destructive manner, offering unparalleled opportunities for developing high‐performance asymmetric optoelectronic systems. [ABSTRACT FROM AUTHOR]

The elementary electronic‐logic‐gates, performing basic logic functions using electric signals as input, act as a building block of modern digital circuits. Intriguingly, the optoelectronic‐logic‐gates (OLGs), composed of optical devices, are emerging as a new logic platform which enables faster and large‐capacity data transmission and processing by using photons as input. However, the strict operation principle of classic optical devices, for example, the unidirectional photoresponse of the photodetector, restricts the functional enrichment of OLGs. Herein, reprogrammable OLGs in a photoelectrochemical (PEC)‐environment are reported by employing gallium‐nitride semiconductor p–n nanowires as photoelectrodes where bidirectional photocurrent is achieved, leading to the demonstration of various binary OLGs including "NOT", "XOR", and "OR". Strikingly, thanks to the versatile tunability of PEC‐photoelectrodes, the logic function of these OLGs is switchable by simply adjusting programming inputs including light intensity, bias voltage, electrolyte condition, and the physicochemical properties of the nanowire surface. Most importantly, unique ternary OLGs, for example, ternary "OR" gates, can also be realized based on binary ones by just tuning their applied bias for higher logic complexity applications, without changing the device architecture. Such reprogrammable binary and ternary OLGs could provide a new avenue toward next‐generation logic circuits for fast computing and data‐processing in the future. [ABSTRACT FROM AUTHOR]

Introduction: This study was to compare the prevalence of stoma‐related complications and stoma reversal perioperative complications of patients with low‐lying rectal cancer who received preventative loop ileostomy and those who underwent loop transverse colostomy. Methods: This retrospective single‐center study analyzed the clinicopathologic and surgical data of 288 patients with pathologically proven primary rectal cancer who underwent anterior resection with either preventative loop ileostomy (n = 82) or loop transverse colostomy. To achieve comparability of a propensity score matching method was used to match patients from each group in a 1:2 ratio. Determinants of stoma‐related complications were analyzed by multivariate logistic regression analysis. Results: Forty‐nine (74.3%) patients in the loop ileostomy group experienced stoma‐related complications versus 48.7% in the loop transverse colostomy group (P < 0.01). Irritant dermatitis was the most frequent complication in both groups. The loop ileostomy group had a significantly higher rate (24.24%) of stoma reversal perioperative complications than the loop transverse colostomy group. Multivariate logistic regression analysis showed that ileostomy versus loop transverse colostomy was a significant independent risk for stoma‐related complications and stoma reversal perioperative complications. Furthermore, by Clavien–Dindo classification, patients receiving loop ileostomy had an overall higher rate of complications and stoma reversal perioperative complications versus those undergoing loop transverse colostomy (P < 0.01). The rate of grade II complications was significantly higher in the loop ileostomy group (43.9%) than that of loop transverse colostomy group (13.5%, P < 0.01), whereas the rate of grade I, and grade IIIa and IIIb complications and stoma reversal perioperative complications was comparable between the two groups. Conclusion: The study has demonstrated that loop transverse colostomy is associated with significantly lower rates of stoma‐related complications and stoma reversal perioperative complications compared to loop transverse colostomy. [ABSTRACT FROM AUTHOR]

Currently, the primary method of identifying high‐ and low‐quality liquors is sensory tasting, which is prone to uncertainty caused by the biases of tasters. To address this problem, this study used color, aroma, taste, and style as four factors affecting the sensory quality of Luzhou‐flavor liquor; determined the weights of each factor; and quantitatively evaluated the sensory quality of five different Luzhou flavor liquor using fuzzy mathematical methods. The volatile aromatic substances in the liquor samples were detected by GC‐MS, and analyzed using principal component analysis. The results obtained from fuzzy mathematics and principal component analysis indicated that the comprehensive evaluation system was scientifically sound and reasonably constructed. [ABSTRACT FROM AUTHOR]

The emerging photoelectrochemical‐type photodetector (PEC‐PD), because of its unique device architecture by using an aqueous electrolyte, is naturally applicable in the pursuit of underwater optical communication without sophisticated device packaging and assembling. Unfortunately, the traditional PEC detecting process typically involves a large electrochemical workstation with long cables and wire connections for photo signal acquisition, which hinders its applications in wireless optical communication. In this work, an AlGaN nanowire‐based self‐powered PEC‐PD is fabricated that uses seawater as an electrolyte, and then an optical communication system including the PEC‐PD and a portable electrochemical workstation as the signal receiver for data communication is built. Essentially, the self‐power PEC‐PD shows a high responsivity of −15.5 mA W–1, a fast response/recovery time of ≈100 ms, and high stability operation in the seawater electrolyte. Foremost, the optical communication system shows high accuracy in wireless transmission of ASCII code signals in a seawater environment. Such a demonstration offers a new device architecture for possible under‐seawater communication systems by leveraging the unique operation principle of photoelectrochemical devices in the future. [ABSTRACT FROM AUTHOR]

Drop‐on‐demand inkjet‐printing has the advantages of high cost‐effectiveness and powerful patterning ability, which can be a promising technique for perovskite pattern deposition. However, by far most of the reported works using inkjet‐printing for perovskite films fabrication are printing solvent‐rich wet precursor layers on the high‐temperature meso‐TiO2 substrate, and subsequently require a vacuum‐assisted thermal annealing process to enhance the crystallization of perovskite precursor, which largely elevates fabrication cost and process complexity. Herein, a heat‐assisted inkjet‐printing process is developed to directly print compact and uniform crystalline perovskite films on the planar PEDOT:PSS substrate under ambient condition. The effects of precursor composition, printing temperature, solvent system, and, especially, the printing parameters on the final morphology and microstructure of the printed perovskite films are systematically studied for the first time and the related crystal growth models are revealed, which provide a constructive guidance for the future studies on ambient inkjet‐printed perovskite films and devices. Based on these studies, a champion power conversion efficiency (PCE) of 16.6% for the ambient printed PSC devices is achieved. This work provides a reliable and cost‐effective approach for the scalable fabrication of perovskite films with a low material consumption. [ABSTRACT FROM AUTHOR]