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Abstract The phase transitions in IrTe2 have been extensively studied but the symmetry at each phase is yet to be settled. Employing second harmonic generation (SHG) measurements over a temperature range of 4 –300 K, we probe the evolution of the symmetry of IrTe2. Our results indicate shifts in two distinct transition temperatures (Ts1 and Ts2 with Ts1 > Ts2) through thermal cycling, providing an explanation for the variations of reported values in literature. The SHG polarimetry measurements identify symmetries in different temperature ranges, confirming the trigonal symmetry above Ts1, the triclinic symmetry between Ts1 and Ts2, and the coexistence of multiple stripe phases below Ts2. The most striking feature is the reemergence of a trigonal phase as reflected by six-fold symmetry below ~ 10 K which is likely responsible for phenomena observed at low temperatures.

Although the SNARC effect in the processing of most magnitude stimuli and sequence stimuli has been reported for the past 30 years, it remains unclear whether this effect is caused by the spatial representation or polarity encoding of stimuli. In the present study, we designed five experiments using a four-way classification task to evaluate the ability of spatial representation theory and polarity encoding theory to explain the SNARC effect in the processing of number and sequence stimuli. In all five experiments in the present study, stimuli (Experiments 1 and 4: four different Arabic numbers, Experiment 2: sequence stimuli, Experiment 3: ordinal sequences relevant to working memory, Experiment 5: Chinese characters without any implicit spatial information) were centrally presented. Participants were asked to respond to specific number or sequence stimuli by pressing the A, S, K, and L keys in consistent trials (or the L, K, S, and A keys in inconsistent trials). The results showed that (1) the SNARC effect occurred in the processing of number and sequence stimuli both when only one specific number was mapped to one specific key (Experiments 1, 2 and 3) and when two numbers were mapped to one specific key (Experiment 4). (2) There was not a SNARC effect when the numbers were replaced with Chinese characters without any implicit spatial information (Experiment 5). The results of these five experiments imply that the SNARC effect in the processing of magnitude stimuli, including numbers and sequences, originates from the spatial representation of stimuli, supporting spatial representation theory.

Abstract The detection of anomalies in high-dimensional time-series has always played a crucial role in the domain of system security. Recently, with rapid advancements in transformer model and graph neural network (GNN) technologies, spatiotemporal modeling approaches for anomaly detection tasks have been greatly improved. However, most methods focus on optimizing upstream time-series prediction tasks by leveraging joint spatiotemporal features. Through experiments, we found that this modeling approach not only risks the loss of some original anomaly information during data preprocessing, but also focuses on optimizing the performance of the upstream prediction task and does not directly enhance the performance of the downstream detection task. We propose a spatiotemporal anomaly detection model that incorporates an improved attention mechanism in the process of temporal modeling. We adopt a heterogeneous graph contrastive learning approach in spatio modeling to compensate for the representation of anomalous behavioral information, thereby guiding the model through thorough training. Through validation on two widely used real-world datasets, we demonstrate that our model outperforms baseline methods. We also explore the impact of multivariate time-series prediction tasks on the detection task, and visualize the reasons behind the benefits gained by our model.

In recent years, contamination of mineral oil hydrocarbons (MOH) in milk powder, especially infant formula, has become a public concern, and related international regulation has gradually escalated. However, there is no standard method for the determination of MOH in milk powder. In this paper, the sample pretreatment method based on the EU limits and analytical requirements were improved and optimized, and the saponification method, hexane extraction, silica gel clean-up, epoxidation reaction method in order were used, and a highly sensitive method for the determination of mineral oils of saturated hydrocarbons (MOSH) and mineral oils of aromatic hydrocarbons (MOAH) in milk powder by on-line high performance liquid chromatography-gas chromatography (HPLC-GC) were established. Results showed that, the method achieved a limit of quantification (LOQ) of 0.5 mg/kg and recoveries of 81.1%~112.0% (RSD=0.3%~3.8%), meeting the method requirements of the European Joint Research Center (JRC). The method was applied to analyze the international proficiency testing samples, and the results showed the detection results of MOSH and MOAH from C16 to C25 and C25 to C35 were close to the true values, and the absolute values of their z'-scores were less than 2. This indicated that the method passed the validation, and the method could be referred to as the standard for the determination of MOSH and MOAH in milk powder.

Abstract Neuroplasticity research supports the idea that varied practice and new environments promote cognitive engagement and enhance learning. Expanding on a meta-analysis of the effect of physical activity interventions on cognition and academic outcomes, we reviewed and quantified the impact of task and environmental factors that foster creative physical activity. Interventions were considered as fostering creative physical activity to a greater extent if (1) they were varied, (2) relied less on technical acquisition, instruction or demonstration, (3) involved open spaces, props, or open-ended instructions, and (4) involved interactions with peers. A wide range of physical activities were considered, from dance to aerobic exercise across 92 studies in 5–12-year-old children. Creativity ratings of physical activity interventions were varied but did not associate with greater beneficial effects on executive functions (k = 45), academic achievement (k = 47), or fluid intelligence (k = 8). Studies assessing on-task behaviour (k = 5) tended not to foster creativity, while reversely studies assessing creativity tended to foster creative physical activities (k = 5). As a group, three studies that fostered more creative PA showed a small significant negative summary effect on cognitive flexibility. Considering qualitative differences in the physical activities performed in schools will improve our understanding of their mechanisms of impact. Future research should consider using more varied measures, including more proximal outcomes that involve body movements (e.g., a Simon Says task to measure inhibitory control).

A method for the high-sensitive determination of mineral oil hydrocarbons (MOH) in vegetable oil-based canned fish was established, and applied in some commercial products. The samples were extracted and purified by saponification and epoxidation, and were fractionated, concentrated and quantitatively determined by on-line high performance liquid chromatography coupled with gas chromatography (HPLC-GC) for mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH). The results showed that the limit of quantification (LOQ) of the method was 0.5 mg/kg and the spiked recovery was 90.0%~106.0%, and the precision (RSD) was 1.6%~12.7%, which met the requirements of the European Joint Research Center (JRC) for the analysis of MOH in the higher-fat/oil-content foods. This method was applied to detect ten canned fish products sold in Beijing. It was found that all of those contained MOSH with contents of 2.6~53.7 mg/kg, of which five detected MOAH with a content of 0.7~5.5 mg/kg. The MOH chromatographic profiles indicated that the contaminants were closely related to the sources of the vegetable oils and fish meat in those products.

Abstract Microbial weathering processes can significantly promote soil properties and reduce rock-to-soil ratio. Some soil-inhabiting bacteria exhibit efficient rock-dissolution abilities by releasing organic acids and other chemical elements from the silicate rocks. However, our understanding of the molecular mechanisms involved during bacterial rock-dissolution is still limited. In this study, we performed silicate rock-dissolution experiments on a Pseudomonas sp. NLX-4 strain isolated from an over-exploited mining site. The results revealed that Pseudomonas sp. NLX-4 strain efficiently accelerates the dissolution of silicate rocks by secreting amino acids, exopolysaccharides, and organic acids. Through employing genome and transcriptome sequencing (RNA-seq), we identified the major regulatory genes. Specifically, 15 differentially expressed genes (DEGs) encoding for siderophore transport, EPS and amino acids synthesis, organic acids metabolism, and bacterial resistance to adverse environmental conditions were highly up-regulated in silicate rock cultures of NLX-4 strain. Our study reports a potential bacterial based approach for improving the ecological restoration of over-exploited rock mining sites. Graphical Abstract

Abstract The biological pretreatment for the enzymatic hydrolysis of lignocellulosic biomasses depends exclusively on the effective pretreatment process. Herein, we report a significant enhancement of enzymatic saccharification obtained with corn stover using a bacterial strain Bacillus sp. P3. The hemicellulose removal from corn stover by the strain Bacillus sp. P3 was evaluated for enhancing subsequent enzymatic hydrolysis. Therefore, our study revealed that an alkaline-resistant xylanase as well as other enzymes produced by Bacillus sp. P3 in fermentation broth led to a substantially enhanced hemicellulose removal rate from corn stover within pH 9.36–9.68. However, after a 20-day pretreatment of corn stover by the strain P3, the glucan content was increased by 51% and the xylan content was decreased by 35%. After 72 h of saccharification using 20 U/g of commercial cellulase, the yield of reducing sugar released from 20-day pretreated corn stover was increased by 56% in comparison to the untreated corn stover. Therefore, the use of the strain P3 could be a promising approach to pretreat corn stover for enhancing the enzymatic hydrolysis process of industrial bioenergy productions.

Lead-free perovskites of Cs3Sb2X9 (X = Cl, Br, or I) have attracted wide attention owing to their low toxicity. High pressure is an effective and reversible method to tune bandgap without changing the chemical composition. Here, the structural and photoelectric properties of Cs3Sb2X9 under high pressure were theoretically studied by using the density functional theory. The results showed that the ideal bandgap for Cs3Sb2X9 can be achieved by applying high pressure. Moreover, it was found that the change of the bandgap is caused by the shrinkage of the Sb-X long bond in the [Sb2X9]3− polyhedra. Partial density of states indicated that Sb-5s and X-p orbitals contribute to the top of the valence band, while Sb-5p and X-p orbitals dominate the bottom of the conduction band. Moreover, the band structure and density of states showed significant metallicity at 38.75, 24.05 GPa for Cs3Sb2Br9 and Cs3Sb2I9, respectively. Moreover, the absorption spectra showed the absorption edge redshifted, and the absorption coefficient of the Cs3Sb2X9 increased under high pressure. According to our calculated results, the narrow bandgap and enhanced absorption ability under high pressure provide a new idea for the design of the photovoltaic and photoelectric devices.

The present study investigated the multi-scale structure of starch derived from acorn kernels and the effects of the non-starch nutrients on the physicochemical properties and in vitro digestibility of starch. The average polymerization degree of acorn starch was 27.3, and the apparent amylose content was 31.4%. The crystal structure remained as C-type but the relative crystallinity of acorn flour decreased from 26.55% to 25.13%, 25.86% and 26.29% after the treatments of degreasing, deproteinization, and the removal of β-glucan, respectively. After the above treatments, the conclusion temperature of acorn flour decreased and had a significant positive correlation with the decrease in the crystallinity. The aggregation between starch granules, and the interactions between starch granules and both proteins and lipids, reduced significantly after degreasing and deproteinization treatments. The endogenous protein, fat, and β-glucan played key roles in reducing the digestibility of acorn starch relative to other compounds, which was dictated by the ability for these compounds to form complexes with starch and inhibit hydrolysis.

Abstract Background Cellulases played an important role in the production of bioenergy and bio-products. Cellulases from bacteria with some special characteristics drew great attention due to its fast growth speed, wide adaption to harsh environment, and production of multi-function cellulases. Results An endoglucanase gene egls from Bacillus velezensis A4 was cloned and expressed in Escherichia coli BL21 (DE3). The recombinant enzyme Egls was partially purified using aqueous two-phase system. The highest recovery rate of the enzyme was 90.39% at PEG 4000 (25% w/w), phosphate buffer 8.08% (w/w) (pH 6.0), and NaCl (5% w/w). The enzyme molecular weight was 55 KD estimated by zymogram. The optimal pH and temperature of recombinant enzyme Egls were pH 6.0 and 55 °C, respectively. The enzyme was stable at pH range of 5.0–7.0 at 55 °C for 60 min. The enzyme exhibited K m, V max, K cat values as 63.38 mg/ml, 55.6 mg/min, and 3.93 × 103/S, respectively. The addition of 10 mM of Mg2+, Mn2+, or 5% (w/w) of Triton-X 100 in the reaction system enhanced the enzyme activity significantly. The enzyme showed both endoglucanase and exoglucanase activity. Conclusions An endoglucanase gene egls from B. velezensis A4 was cloned and expressed in E. coli BL21 (DE3). The recombinant enzyme Egls was purified by aqueous two-phase system and characterized. The enzyme can be applied for the efficient pretreatment of lignocellulosic biomass for bioenergy and bio-products production.

The transfer of surface heat between a building and the outdoor environment is the energy transfer channel and it is important for the energy efficiency of buildings. Early stage building design is a critical stage and it can directly determine the energy consumption by a building. Therefore, selecting appropriate surface heat transfer coefficients (SHTCs) is a key issue in building energy consumption prediction. In this study, EnergyPlus was employed to investigate the building load in Chinese cities with different SHTCs: (1) constant SHTCs based on national standards; and (2) dynamically changing SHTCs based on the Thermal Analysis Research Program (TARP). Based on investigations of the hourly load, daily cumulative load in a typical day, and annual cumulative load with different SHTCs, corrections for the annual cumulative load were obtained according to the relative deviations between the results produced with the TARP model and traditional SHTCs. The greatest relative deviations were 67.5% and 25.3% for the building shape factor φ = 0.49 and 0.29 in Lhasa. The relative deviations were 13.3% and 12.0% for φ = 0.49 in Xi’an and Beijing, respectively. Corrections were not essential for other conditions because the relative deviations were lower than 5.0%. Considering the current characteristics of engineering calculations and the need to obtain more accurate design results, dynamically changing SHTCs should be applied. These correction factors can obtain more accurate results for the current building energy efficiency system with traditional SHTCs.

Abstract Background Changes in platelet concentration are common in severe burn patients. Platelets play a key role in the course of disease. This study aims to explore the significance of platelet concentration during the course of the disease in victims of a mass burn casualty. Methods A total of 180 patients were involved in the “8.2” Kunshan explosion accident in China. The examined data included age, gender, total burn area (% TBSA), third-degree burn area (% TBSA), and platelet concentration within the first 5 days after the burn injury. The patients were divided into two groups according to four indicators (resuscitation, acute respiratory distress syndrome, acute kidney injury, septic shock). We collected several types of data for the patients and divided the patients into a complication group and non-complication group according to the diagnostic criteria. We analyzed the platelet concentration of the two groups using t tests to determine whether significant differences were present. P values

Low-toxicity, air-stable cesium bismuth iodide Cs3Bi2X9 (X = I, Br, and Cl) perovskites are gaining substantial attention owing to their excellent potential in photoelectric and photovoltaic applications. In this work, the lattice constants, band structures, density of states, and optical properties of the Cs3Bi2X9 under high pressure perovskites are theoretically studied using the density functional theory. The calculated results show that the changes in the bandgap of the zero-dimensional Cs3Bi2I9, one-dimensional Cs3Bi2Cl9, and two-dimensional Cs3Bi2Br9 perovskites are 3.05, 1.95, and 2.39 eV under a pressure change from 0 to 40 GPa, respectively. Furthermore, it was found that the optimal bandgaps of the Shockley–Queisser theory for the Cs3Bi2I9, Cs3Bi2Br9, and Cs3Bi2Cl9 perovskites can be reached at 2–3, 21–26, and 25–29 GPa, respectively. The Cs3Bi2I9 perovskite was found to transform from a semiconductor into a metal at a pressure of 17.3 GPa. The lattice constants, unit-cell volume, and bandgaps of the Cs3Bi2X9 perovskites exhibit a strong dependence on dimension. Additionally, the Cs3Bi2X9 perovskites have large absorption coefficients in the visible region, and their absorption coefficients undergo a redshift with increasing pressure. The theoretical calculation results obtained in this work strengthen the fundamental understanding of the structures and bandgaps of Cs3Bi2X9 perovskites at high pressures, providing a theoretical support for the design of materials under high pressure.

Ultrathin inorganic halogenated perovskites have attracted attention owing to their excellent photoelectric properties. In this work, we designed two types of Ruddlesden–Popper hybrid perovskites, Csn+1SnnBr3n+1 and CsnSnn+1Br3n+2, and studied their band structures and band gaps as a function of the number of layers (n = 1–5). The calculation results show that Csn+1SnnBr3n+1 has a direct bandgap while the bandgap of CsnSnn+1Br3n+2 can be altered from indirect to direct, induced by the 5p-Sn state. As the layers increased from 1 to 5, the bandgap energies of Csn+1SnnBr3n+1 and CsnSnn+1Br3n+2 decreased from 1.209 to 0.797 eV and 1.310 to 1.013 eV, respectively. In addition, the optical absorption of Csn+1SnnBr3n+1 and CsnSnn+1Br3n+2 was blue-shifted as the structure changed from bulk to nanolayer. Compared with that of Csn+1SnnBr3n+1, the optical absorption of CsnSnn+1Br3n+2 was sensitive to the layers along the z direction, which exhibited anisotropy induced by the SnBr2-terminated surface.

Abstract Background Occupational stress is an important risk factor for mental health among occupational population. Exploring related mediators of workers’ mental health are important to improve their health and performance. Our study aims to explore the relationships between work stress, positive psychological resources, burnout and well-being. Methods The study was performed during the period of June and July in 2015. A questionnaire that consisted of the Effort-reward Imbalance Scale, the Maslach Burnout Inventory-General Survey, the Psychological Capital Questionnaire, the Rosenberg Self-esteem Scale, the Flourishing Scale, as well as demographic and working factors. Results Psychological capital mediated the associations of effort-reward imbalance and emotional exhaustion, cynicism, professional efficacy and well-being. Self-esteem mediated the associations of effort-reward imbalance ratio with cynicism, professional efficacy and well-being, and mediated the associations of overcommitment and cynicism, professional efficacy and well-being. Conclusions The findings indicated that enhancing positive psychological resources could be considered in developing intervention strategies for psychological health among manufacturing employees.

Abstract We report longer surface plasmon polariton propagation distance based on crystalline crystal silver at low temperature. Although enhanced plasmonic performance at low temperature has been predicted for a long time, it has not been directly observed on polycrystalline silver films which suffer from significant plasmonic losses due to grain boundaries and rough silver surface. Here we show that longer propagation distance can be achieved with epitaxial silver at low temperature. Importantly, the enhancement at low temperature are consistent across silver films grown with different methods.

The current study investigated how the spatial position of nonsymbolic numbers on the mental number line influenced responses when stimuli contained spatial (orientation) and magnitude information. Different numbers of rectangles (Experiment 1), leftward and rightward arrows (Experiments 2, 3 and 4), or double-headed arrows (Experiment 5) were centrally presented to participants who were asked to classify these stimuli according to the parity (i.e., evenness) of the number of rectangles (Experiment 1), arrow orientation (Experiment 2), parity of the number of arrows (Experiment 3), numbers of leftward and rightward arrows (Experiment 4), or parity of the number of double-headed arrows (Experiment 5). The results showed that (a) the spatial-numerical association of response codes (SNARC) effect was present in the rectangle parity (Experiment 1) and the double-headed arrow parity (Experiment 5) classification, but that (b) despite the association between arrow orientation and response, no SNARC effect was observed in the arrow orientation (Experiment 2), arrow parity (Experiment 3) or arrow magnitude (Experiment 4) classification tasks. These results indicate that spatial cues and nonsymbolic numbers interact to create systematic spatial-numerical associations. [ABSTRACT FROM AUTHOR]