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Narrowband photodetector (NB‐PD) with selective light detection is critical for artificial vision and imaging. Intrinsic (optical‐filter‐free) NB‐PDs using conjugated organics or halide perovskite materials have been developed for eliminating the current complex filtering systems in NB‐PDs. However, the poor performance and external driving circuit of organic NB‐PDs as well as complex doping and uncontrollable recombination reactions in typical perovskite NB‐PDs have limited their applicational diversification. A p‐type self‐doped perovskite for intrinsic NB detection is reported which exhibits unique unbalanced electron–hole transfer kinetics. In conjunction with the optical field distribution, an unbalanced charge transport within the self‐doped perovskite triggers a wavelength‐dependent photo‐carrier collection, resulting in a novel spontaneous internal quantum efficiency narrowing mechanism. As a result, by reverting the device architectural polarity, an NB detection at a monochromic light of either red or UV is observed. Using such a revertible asymmetric device design, self‐powered NB‐PDs are successfully achieved. Briefly, the corresponding NB‐PDs exhibit excellent narrow response with a response window of ≈100 nm, high detectivity ≈1011 Jones, and fast response speed (f−3dB ≈ 60 kHz) at zero bias. These results demonstrate a new strategy of manipulating internal charge transport to realize power‐free and filter‐free intrinsic NB‐PDs. [ABSTRACT FROM AUTHOR]

With the power conversion efficiencies of perovskite solar cells (PSCs) exceeding 25%, the PSCs are a step closer to initial industrialization. Prior to transferring from laboratory fabrication to industrial manufacturing, issues such as scalability, material cost, and production line compatibility that significantly impact the manufacturing remain to be addressed. Here, breakthroughs on all these fronts are reported. Carbon‐based PSCs with architecture fluorine doped tin oxide (FTO)/electron transport layer/perovskite/carbon, that eliminate the need for the hole transport layer and noble metal electrode, provide ultralow‐cost configuration. This PSC architecture is manufactured using a scalable and industrially compatible electrospray (ES) technique, which enables continuous printing of all the cell layers. The ES deposited electron transport layer and perovskite layer exhibit properties comparable to that of the laboratory‐scale spin coating method. The ES deposited carbon electrode layer exhibits superior conductivity and interfacial microstructure in comparison to films synthesized using the conventional doctor blading technique. As a result, the fully ES printed carbon‐based PSCs show a record 14.41% power conversion efficiency, rivaling the state‐of‐the‐art hole transporter‐free PSCs. These results will immediately have an impact on the scalable production of PSCs. [ABSTRACT FROM AUTHOR]

The discounted {0–1} knapsack problem (D{0–1}KP) is a kind of knapsack problem with group structure and discount relationships among items. It is more challenging than the classical 0–1 knapsack problem. A more effective hybrid algorithm, the discrete hybrid teaching-learning-based optimization algorithm (HTLBO), is proposed to solve D{0–1}KP in this paper. HTLBO is based on the framework of the teaching-learning-based optimization (TLBO) algorithm. A two-tuple consisting of a quaternary vector and a real vector is used to represent an individual in HTLBO and that allows TLBO to effectively solve discrete optimization problems. We enhanced the optimization ability of HTLBO from three aspects. The learning strategy in the Learner phase is modified to extend the exploration capability of HTLBO. Inspired by the human learning process, self-learning factors are incorporated into the Teacher and Learner phases, which balances the exploitation and exploration of the algorithm. Two types of crossover operators are designed to enhance the global search capability of HTLBO. Finally, we conducted extensive experiments on eight sets of 80 instances using our proposed approach. The experiment results show that the new algorithm has higher accuracy and better stability than do previous methods. Overall, HTLBO is an excellent approach for solving the D{0–1}KP. [ABSTRACT FROM AUTHOR]

Background: Early dysphagia is a frequent complication of anterior cervical (AC) spine surgery. However, there are no reports that have discussed the correlation between early dysphagia and the positional relationship between thyroid cartilage and the surgical level. Methods: We retrospectively enrolled 82 patients in our hospital who underwent single-level AC discectomy performed by the same surgeon using the same internal fixation apparatus from 2015 to 2017. Swallowing difficulty was rated during the first five postoperative days using a 10-point scoring system. The positional relationship between the thyroid cartilage and the surgical level was defined as discectomy within the thyroid cartilage (IN group) or outside the thyroid cartilage (OUT group) using preoperative computed tomography (CT) images. The confounding factors such as gender, age, body mass index (BMI), hypertension, diabetes mellitus, drinking, smoking, operative level, operative time, and blood loss were analyzed by a binomial logistic regression. Results: The thyroid cartilage was most commonly located above the C5 level (65.1%). Early dysphagia developed in 47.6% of the patients during the first five postoperative days. The IN and OUT groups each contained 41 cases. The difference in the cumulative postoperative early dysphagia score between the IN and OUT groups was statistically significant (p <.05). The factors of gender, age, BMI, hypertension, diabetes mellitus, drinking, smoking, operative level, operative time, blood loss did not significantly influence the incidence of postoperative early dysphagia. Conclusions: We found that early dysphagia, which is a self-limiting complication, was correlated with surgery performed at levels outside the thyroid cartilage region. Preoperative review of the positional relationship between the thyroid cartilage and the surgical level can predict the incidence of postoperative transient dysphagia. [ABSTRACT FROM AUTHOR]

Objective: To develop anthropometric prediction equations for estimating appendicular skeletal muscle (ASM) in Chinese knee osteoarthritis patients. Methods: Subjects were divided into the model development group (MD group: 104 cases, 47 men and 57 women) and cross‐validation group (CV group: 69 cases, 38 men and 31 women). Stepwise multiple linear regression analyses were undertaken in the MD group to identify the best equations. Agreement between the estimated ASM and ASM measured by dual‐energy X‐ray absorptiometry (DXA) was tested in the CV group. Results: Two models were developed in the MD group. Validation in the CV group showed that our models (R2 = 0.83 and R2 = 0.90) had a high coefficient of determination. The mean bias of ASM estimated by the two models from the ASM measured by DXA in the CV group showed no significant difference (P > 0.05). Conclusion: These models could be useful for older Chinese patients with knee osteoarthritis to estimate ASM. [ABSTRACT FROM AUTHOR]

The set-union knapsack problem (SUKP) is a variation of the 0–1 knapsack problem (KP) in which each item is a set of elements, each item has a nonnegative value, and each element has a nonnegative weight. The weight of one item is given by the total weight of the elements in the union of the items' sets. The SUKP accommodates a number of real-life applications and is more complicated and computationally difficult than the 0–1 KP. In this paper, we propose a novel hybrid Jaya algorithm with double coding (DHJaya) to solve the SUKP. In the DHJaya, double coding is used to represent the individual, which includes the solutions for solving the SUKP by adopting a mapping function. The Jaya algorithm and differential evolution algorithm are combined to improve the exploration ability. To enhance the exploitation ability, the Cauchy mutation is performed on some individuals. Meanwhile, an improved repairing and optimization algorithm (MS-GROA) is proposed to repair the infeasible solutions and optimize the feasible solutions. We test the DHJaya using three sets of SUKP instances to demonstrate its efficiency, and the obtained results are compared with those in the previous study. Extensive experiments show a remarkable performance of the proposed approach. [ABSTRACT FROM AUTHOR]

A micro-scale finite element method (FEM) was proposed to precisely calculate the heat conduction between mortar and aggregate, and thus to accurately predict the non-uniformity of concrete pouring temperature. The concrete temperature feld during vibration was also precisely calculated by accurate description of heat absorption characteristics of different parts of concrete when vibration. Based on the above method, the prediction model was used to predict the pouring temperature of a practical engineering. The comparison between actual results and simulated values shows that this method can be adopted to accurately predict the non-uniformity of concrete pouring temperature and the influence of mechanized vibration on concrete pouring temperature, and thus accurately predict pouring temperature. The control of casting temperature is crucial for preventing concrete fracture. The study provides a new method for predicting the pouring temperature of concrete structures, which has great practical value in engineering application. [ABSTRACT FROM AUTHOR]