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• We construct a measure of managerial optimism using textual and nonparametric estimation. • We explore the impact of managerial sentiment on company operational efficiency. • Managerial optimism positively influences stock price returns over the subsequent year. • This research offers practical implications for management at the firm-level. This study constructs a measure of managerial optimism using textual and nonparametric estimation methods, exploring its impact on company operational efficiency and market reactions. Findings indicate that managerial optimism positively influences stock price returns over the subsequent year by enhancing internal operational efficiency and reducing analyst forecast dispersion, with a more pronounced effect in state-owned enterprises. Utilizing information from the MD&A (Manager Discussion and Analysis) section of annual reports, this research demonstrates the role of managerial optimism in company operations and market reactions, offering empirical evidence for corporate behavioral finance research and practical implications for management practice. [ABSTRACT FROM AUTHOR]

Reconfigurable pixel antennas are crucial for advancing wireless communication. However, the increasing number of switches results in exponentially growing complexity in antenna configurations. While the complexity holds promise for performance improvements, it also introduces challenges in physical implementation and requires extensive numerical calculations. Thus, an effective design methodology is essential to address these issues. This paper introduces a novel pixel antenna strategy that utilizes the whale optimization algorithm (WOA) and the minimum percentage of useful configurations (MPUC). As a pioneering concept, MPUC explores the impacts of switches on antenna reconfigurability and evaluates their contributions across different topologies. Dynamically assessing switches, the MPUC determines their statuses cyclically. Ultimately, the most reconfigurable antenna is achieved by optimizing switch configurations while enhancing overall reconfigurability. Leveraging WOA, the final antenna configuration is optimized and derived to meet design specifications. Additionally, a comparison is made between antenna configurations derived from traditional optimization methods and the final antenna configuration. Results reveal the superiority of the proposed method, demonstrating a threefold enhancement in design efficiency and reduced switch configurations to achieve comparable electrical performance. These findings validate the efficacy of the WOA and MPUC based strategy in effectively designing larger-scale pixel antennas. [ABSTRACT FROM AUTHOR]

Hard carbons are perceived as promising anode materials in sodium-ion batteries, while their practical implementation is largely impeded by the insufficient initial Coulombic efficiency (ICE). Hard carbons with self-supporting architecture are intriguing to enhance ICE owing to the omission of binder and conductive agent; whereas elaborate architecture and microstructure design are still required to further raise the ICE to the level of commercial graphite in lithium-ion batteries, especially under high areal capacity. Herein, we propose a graphite-assisted pressurization strategy during carbonization to achieve remarkable ICE and high areal capacity in resulting self-supporting cellulose tissue derived hard carbon anode. The intimate contact of graphite plate enables suitable local ordering of pseudo-graphitic nanodomains with low intrinsic defects, responsible for enhanced ICE. While the pressure-reinforced dense yet self-interwoven fibrous networks render high areal capacity. Consequently, the as-prepared self-supporting hard carbon anode displays remarkable ICE to 95% and areal capacity of 2.4 mAh cm−2, far exceeding the reported value of less than 0.8 mAh cm−2. Meanwhile, the rate and durability are not scarified under such superior ICE due to the well-manipulated pseudo-graphitic nanodomains and porous fibrous networks. The practicality is further demonstrated in coin-type and pouch-type full cells delivering high capacity and long-term stability. Our finding offers an impetus for the development of high ICE and areal capacity for sodium-ion battery anode. [Display omitted] [ABSTRACT FROM AUTHOR]

In this article, a finite-time thermodynamic model of solar-driven two-stage multi-element thermoelectric generator is developed. Considering external heat transfers, radiation loss of collector, Joule heat and Fourier heat leakage, analytical formulas for heat balance equations, power and efficiency are derived. Working temperatures of thermoelectric device are obtained by solving four equations simultaneously, and basic performance of the system is explored. Performance optimization is executed by adjusting electrical current, thermoelectric element distribution and heat exchanger inventory distribution. The optimal allocations for different total thermoelectric element numbers are given by the enumeration method. Influences of various factors on maximal power and efficiency are analyzed, and the upper bounds of power and efficiency are given. Results show that an optimal collector temperature exists to achieve optimal performance for this solar power device. Power and efficiency show the same variation trend, and the efficiency is maximal when power reaches its maximum. The system performance is optimal when external heat transfers and inner structure parameters are optimal. At this time, the corresponding junction temperatures reach their optimal values, the total thermal conductance should be divided in a half to two heat exchangers, and the corresponding thermoelectric element is allocated nearly half to upper generator. [Display omitted] • Power and efficiency of solar-driven two-stage thermoelectric generator are optimized. • External heat transfers, collector radiation loss, Joule heat and heat conduction are considered. • Collector temperature, electrical current, distributions of thermoelectric element and heat exchanger inventory are variables. • Total thermal conductance should be divided in a half to two heat exchangers. • Thermoelectric element should be allocated nearly half to upper generator. [ABSTRACT FROM AUTHOR]

[Display omitted] • A biosensor for sensing intracellular FMN concentration was constructed. • Enabling continuous evolution and screening of gene in vivo. • Successfully create a high-throughput screening platform. • The mutants increased the yield of FMN by more than 8-fold. Flavin mononucleotide (FMN) is the active form of riboflavin. It has a wide range of application scenarios in the pharmaceutical and food additives. However, there are limitations in selecting generic high-throughput screening platforms that improve the properties of enzymes. First, the biosensor in response to FMN concentration was constructed using the FMN riboswitch and confirmed the function of this sensor. Next, the FMN binding site of the sensor was saturated with a mutation that increased its fluorescence range by approximately 127%. Then, the biosensor and the base editing system based on T7RNAP were combined to construct a platform for rapid mutation and screening of riboflavin kinase gene ribC mutants. The mutants screened using this platform increased the yield of FMN by 8-fold. These results indicate that the high-throughput screening platform can rapidly and effectively improve the activity of target enzymes, and provide a new route for screening industrial enzymes. [ABSTRACT FROM AUTHOR]

Approximate multipliers are widely used in error-tolerant applications to improve circuit performance. For signed multiplication, previous approximate Booth multipliers usually have a large relative error with operands around "0", while approximate leading one detector based (LOD-based) multipliers are not energy-efficient due to the extra preprocessing module. In this paper, a low relative error leading one/zero detector based approximate multiplier (LOZDAM) is proposed for signed multiplication, which dynamically truncates the operands according to the location of their most significant bits for signed complement data. Its accuracy can be configured to suit fault-tolerant applications with different accuracy requirements. A compensation strategy is proposed to reduce the calculation error of LOZDAMs at a low cost. All proposed designs are evaluated in 28nm/0.9 V/TT/25 °C CMOS. Compared with the exact design, the proposed LOZDAM6/7/8/9 with the width of Booth multiplier being 6/7/8/9-bit reduces average power by 64%/43%/33%/21%, with the mean relative error distance by 2.94%/1.46%/0.73%/0.36%, respectively. Case studies of image sharpening and serial Fast Fourier Transform system both show acceptable error and good power/area savings, which verifies the feasibility of our designs. In general, our proposed LOZD-based approximate multipliers achieve both high accuracy and low power. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple and safe liquid seal approach for oxygen-tolerant ATRP. • No deoxygenation operations and post-treatment. • Sufficient heat and mass transfer allowed at a high stirring speed. • Obtained well-defined polymers on a large scale with high conversion. Trace oxygen is fatal to the conventional reversible deactivation radical polymerization (RDRP), so it is necessary to eliminate the influence of oxygen through some strict deoxygenation operations or by adding external components (post-treatment required). Here, we report the effective barrier of oxygen dissolution in an open system built by a liquid seal. Two different liquid seal materials, liquid paraffin and lithium grease, are used in this work. Lithium grease materials can stably isolate oxygen at a high stirring speed (450 rpm) to intensify the heat and mass transfer processes during the reaction. An effective atom transfer radical polymerization (ATRP) could be assisted by simply adding liquid seal materials with a thickness of 5 mm, providing polymers with high conversion (≥90 %), controlled molecular weight, narrow molecular weight distribution (M w / M n ≤ 1.15) and high end-group fidelity. With this liquid seal strategy, dozens of grams of the polymer were obtained, which is expected to have potential industrial applications under ambient atmosphere and conditions. [ABSTRACT FROM AUTHOR]

Flexible composites with manganese oxides (MnO x ) nanocrystals encapsulated in electropun carbon nanofibers were successfully fabricated via a simple and practical combination of electrospinning and carbonization process. The as-formed MnO x /carbon nanofibers composites have a rough surface with MnO x nanoparticles well embedded in the carbon nanofibers backbones. When used as electrodes for supercapacitor, the resulting MnO x /carbon nanofiber composites exhibit good electrochemical performance with a specific capacitance of 174.8 F g −1 at 2 mV s −1 in 0.5 M Na 2 SO 4 electrolyte, a good rate capability at high current density and long-term cycling stability. It is expected that such freestanding composites could be promising electrodes for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

High temperature titanium alloys are being urgently developed owing to the requirements of advanced aerospace industry. Performance of the alloys in service under high-temperature environments always attracts great attention. In this study, variations of microstructure and mechanical property in TC25 (Ti-6.5Al-2Mo-1Zr-1Sn-1 W-0.2Si) dual-phase high temperature titanium alloy subjected to thermal exposure have been systematically investigated by coupling microstructural characterization, compositional analyses and mechanical measurement. It is found that strength is significantly enhanced while ductility is sharply degraded when the alloy is thermally exposed at 550 °C for a long duration of 100 h. Microstructural observations manifest that ternary α -needles (α t) are drastically precipitated from β -ligaments inside transformed β -matrix (β trans) whilst α 2 (Ti 3 Al)-phase is produced from primary α- phase (α p) through ordered transformation. The precipitation of α t -needles is promoted by β -phase metastability resulting from insufficient element partitioning in the initial microstructure. The β -phase stability also renders α t -precipitation encounter size effect of β -ligaments, where the precipitation is suppressed when β -ligaments are thin in size. Both precipitation of α t -needles and α 2 -phase triggers precipitation-hardening effect, which results in strain localization and thereby regresses alloy ductility. However, further analysis indicates that compared with α 2 -phase, α t -precipitation plays more adverse role in embrittlement in the current alloy. This is different from thermal-exposed behavior of most of high temperature titanium alloys reported in literatures. These findings enrich our fundamental understanding on thermal stability of high temperature titanium alloys, and provide plausible implication to improve high temperature performance via controlling phase precipitation. • Thermal stability of TC25 high-temperature titanium alloy was investigated. • α t -needles and α 2 -particles are respectively precipitated from β -matrix and α p -phase. • Both α t and α 2 -precipitation results in strain localization and alloy embrittlement. • α t -precipitation plays more adverse role in alloy embrittlement than α 2 -phase. [ABSTRACT FROM AUTHOR]

Previous studies have shown that dependent individuals (DIs) have higher rates of childhood maltreatment and poorer cognitive performance compared with healthy controls. However, little attention has been paid to the cognitive dysfunction of DIs with childhood maltreatment. The purpose of this study was to explore the cognitive deficits of maltreated methamphetamine-dependent individuals (METH-DIs) using a cross-sectional and case-control design. In addition, we aimed to examine the prevalence of childhood maltreatment and the demographic and clinical characteristics of Chinese male METH-DIs. 330 METH-DIs and 143 healthy controls were recruited and completed a detailed questionnaire on demographic and drug-related variables. Childhood abuse data were collected from the Childhood Trauma Questionnaire-Short Form (CTQ-SF). Cognitive function was assessed by the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The Beck Depression Inventory, Beck Anxiety Inventory, and Visual Analogue Scale (VAS) were used to assess the clinical state of the METH-DIs. 166 of 326 (50.9%) METH-DIs had experienced at least one type of childhood maltreatment. Maltreated METH-DIs were more likely to have a lower level of education (t 324 = 5.81, p < 0.001), a higher level of depression(t 324 = －2.68, p < 0.01), and a younger onset age of drug use (t 324 = 3.58, p < 0.01) than METH-DIs who had no experience of childhood maltreatment. Maltreated METH-DIs also performed worse on the RBANS attention score than METH-DIs who did not experience maltreatment (F 1,324 = 15.41, p < 0.001, partial η 2 = 0.05). Our findings revealed that some demographic and clinical variables were associated with maltreatment among METH-DIs. Moreover, attention dysfunction was found in maltreated METH-DIs, which conforms to the theory of latent vulnerability. [ABSTRACT FROM AUTHOR]

Abstract Background This study aimed to evaluate the performance of HbA1c measurement systems quantitatively with sigma metric and promote the quality improvement. Methods 1066 laboratories enrolled external quality assessment (EQA) and reported their internal quality control (IQC) data for HbA1c in 2017 were included in this study. The bias and coefficient of variation were collected from EQA and IQC program designed by the National Center for Clinical Laboratory. The σ values was used to assess the performance of HbA1c, and combine Westgard Sigma Rules™ to select proper quality control rules in every laboratory. Results Totally, There were 388,190,185,100,59,55,89 participants used Bia-Rad HPLC, TOSOH G7/G8, ARKRAY HA8160/8180, HUIZHONG MQ-2000/2000PT, Roche, Primus HPLC and "Others" system, respectively. "HUIZHONG MQ-2000/2000PT" group had the smallest variation of bias. 56.19% (599/1066) of laboratories met bias criterion and 55.63% (593/1066) satisfied imprecision criterion. However, sigma metrics indicated that 80.21% (855/1066) of 1066 laboratories needed to improve their performance of HbA1c. Moreover, "TOSOH G7/G8" group had the highest constituent ration of σ ≥ 3. Conclusions The analytical quality of HbA1c in most laboratories need improving. Laboratories should pay more attention on the performance of HbA1c, and EQA organizers in China should improve evaluation criteria and push standardization work for HbA1c. Highlight • 80.21% of laboratories need to improve performance of HbA1c and only 2.63% of laboratories reached the top level (σ≥6). • 56.19% of laboratories satisfied bias criteria, and 55.63% of laboratories obtained intra-laboratory CV less than 1/3TEa. • TOSOH G7/G8 had the highest constituent ration of σ≥3 among all groups. • Laboratories should focus more on performance of HbA1c, and use six sigma metric to improve the quality level. • EQA organizers should improve the evaluation criteria and push standardization work for HbA1c. [ABSTRACT FROM AUTHOR]

Confined catalysis is an effective strategy to deal with the low utilization of active sites and poor cyclic stability in metal catalysts. However, the impact of confinement effect on the catalytic degradation process of organic pollutants is unclear. A hollow sulfur doped multilayer carbon shell wrapped cobalt iron alloy catalyst (CoFe@CS) is designed here to activate peroxymonosulfate (PMS) for bisphenol A (BPA) degradation. The hollow porous multilayer carbon shell provides a confined space for the rapid interface adsorption of PMS and in-situ degradation of BPA, which contribute to the superior BPA removal rate of nearly 100% within 20 min. Moreover, confinement catalysis favors the anti-interference ability to cope with changes in solution conditions like pH, organic matter, inorganic anions, etc., which favors the application in realistic wastewater. X-ray photoelectron spectroscopy (XPS) results demonstrate that the crucial Co2+ sites are regenerated by sulfur reduction, ensuring the sustainable use. Electrochemical analysis and density functional theory (DFT) calculations reveal that S doping improves the electron transfer capability and chemical reactivity of CoFe@CS, which drives direct oxidation as the dominant pathway for BPA degradation. The CoFe@CS/PMS system could efficiently mineralize BPA (up to 87.74%) and reduce residual toxicity. This work not only provides a reference for the design of efficient and stable transition metal catalysts but also offers a new insight into the confined degradation research of BPA in advanced oxidation technologies. [Display omitted] • Multilayer carbon shell enhances the adsorption energy of PMS on the catalyst. • The hollow structure provides a confined space for PMS activation and BPA degradation. • The dominant pathway of direct oxidation is systematically confirmed. • CoFe@CS exhibits excellent anti-interference ability. [ABSTRACT FROM AUTHOR]

To date, the pattern of heroin- and methamphetamine-induced cognitive impairment is unclear, especially in the Chinese population. The aim of this study was to compare the similarity and heterogeneity of cognitive impairment between heroin and methamphetamine-dependent patients and to link cognitive impairment to drug-related variables. 567 pure methamphetamine patients, 78 pure heroin patients and 201 healthy volunteers participated in this study. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was used to assess cognitive function including immediate memory, visuospatial/constructional index, language, attention, delayed memory, and total scores. Methamphetamine-dependent and heroin-dependent patients performed significantly worse on all RBANS subtest and total scores (all p < 0.05). Moreover, methamphetamine-dependent patients had more delayed memory impairment than heroin-dependent patients (p = 0.02). In addition, some drug-related variables, such as duration of abstinence, age at first drug use, and duration of drug use, were independently associated with memory and visuospatial/constructional index in methamphetamine patients (all p < 0.05). In contrast, none of the drug-related variables were associated with cognitive performance in heroin patients (all p > 0.05). Chronic heroin and methamphetamine patients may exhibit different patterns of cognitive deficits. • Methamphetamine and heroin patients overlapped in some cognitive impairments. • Methamphetamine patients performed worse on delayed memory. • Methamphetamine and heroin patients may have different patterns of cognitive deficits. [ABSTRACT FROM AUTHOR]

Abstract: This study aimed to generate a monoclonal antibody (mAb) targeting both tumor necrosis factor-α (TNF-α) and receptor activator of NF-κB ligand (RANKL) and to evaluate the therapeutic effects of this antibody on acute inflammation and osteoporosis. We used hybridoma techniques to generate potential mAbs and enzyme-linked immunosorbent assay (ELISA) to determine their specificity. Crystal violet staining was performed to measure the effective dose of the candidate mAbs. The neutralizing effect of the mAbs was evaluated by TNF-α-mediated cytotoxicity and RANKL-induced osteoclastogenesis assays. We further assessed the therapeutic effect of the mAbs in BALB/c mice with carrageenan-induced acute inflammation and ovariectomy-induced osteoporosis. We successfully generated an IgG1 isotype mAb that recognizes human TNF-α and RANKL, which we named 8G12. The 50% effective dose of 8G12 was approximately 1μg/mL. L929 cells treated with 8G12 exhibited decreased levels of apoptosis (20.04% compared to 63.28% in the positive controls). In addition, treatment with 8G12 inhibited osteoclastogenesis in a dose-dependent manner in vitro. Carrageenan-induced paw edema was significantly reduced in the 8G12-treated mice compared to the positive controls. Treatment with 8G12 also reduced the number of infiltrating leukocytes by more than 50%. The 8G12 treatment not only prevented bone loss but also increased the number, thickness and volume of trabeculae and reduced trabecular separation in ovariectomized mice. Our data suggest that the 8G12 effectively neutralizes the bioactivity of TNF-α and RANKL, ameliorating osteoporosis and inflammation. We therefore propose that 8G12 could be a candidate for generating therapeutic antibodies for treating inflammatory bone diseases. [Copyright &y& Elsevier]

[Display omitted] • Hypoxia induced down regulation of purine metabolism related genes and up regulation of nitrogen metabolism genes tnrA and glnR in B. subtilis. • Knockout of the purR and knockdown of the tnrA and glnR genes significantly increased the production of riboflavin. • Dynamically control the expression of the vgb gene, and further increase the production of riboflavin by increasing the utilization of oxygen by the cells. • The final engineered strain had increased riboflavin production by 45.51% compared to the initial strain. Riboflavin, an essential vitamin for animals, is used widely in the pharmaceutical industry and as a food and feed additive. The microbial synthesis of riboflavin requires a large amount of oxygen, which limits the industrial-scale production of the vitamin. In this study, a metabolic engineering strategy based on transcriptome analysis was identified as effective in increasing riboflavin production. First, transcriptional profiling revealed that hypoxia affects purine, and nitrogen metabolism. Next, the precursor supply pool was increased by purR knockout and tnrA and glnR knockdown to balance intracellular nitrogen metabolism. Finally, increased oxygen utilization was achieved by dynamically regulating vgb. Fed-batch fermentation of the engineered strain in a 5-liter bioreactor produced 10.71 g/l riboflavin, a 45.51% higher yield than that obtained with Bacillus subtilis RF1. The metabolic engineering strategy described herein is useful for alleviating the oxygen limitation of bacterial strains used for the industrial production of riboflavin and related products. [ABSTRACT FROM AUTHOR]