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The purpose of this work is to develop dual drug-loaded poly (lactic-co-glycolic acid) (PLGA) fiber-microsphere composite scaffolds with desired morphologies and dual drug loading properties, and to investigate the release kinetics of the dual drugs, both hydrophobic and hydrophilic, from the composite scaffolds. In this study, simvastatin (SIM) and bovine serum albumin (BSA) were used as model drugs, which were incorporated into the composite scaffolds by performing electrospinning and emulsion electrospraying simultaneously. The optimum condition for electrospraying (solution concentration: 0.06 g/mL; applied voltage: 15 kV; and flow rate: 0.6 mL/h) has been obtained to prepare PLGA microspheres. The release rate of SIM and BSA from the composite scaffolds fit the first order kinetics and the Higuchi model, respectively. The results indicated that fiber-microsphere composite scaffolds had the ability to load two types of drug, suggesting the scaffolds have great potential in the field of tissue engineering and combined therapies. [ABSTRACT FROM AUTHOR]

The ZrB2-SiC-graphite composite is one of the most promising ceramics, which show significant potential in manufacturing parts served in ultra-high temperature. Micro-electrical discharge machining (micro-EDM) is an effective method in machining this conductive hard ceramic. However, the recast layer characterized by craters and micro-cracks is formed on the machined surface, resulting in poor surface quality. In this paper, micro-EDM and micro-ultrasonic machining (micro-USM) combined milling is proposed for manufacturing 3D micro-cavities in the ZrB2-SiC-graphite composite. The micro-cavity is firstly machined by micro-EDM milling, followed by micro-USM finish milling to remove the recast layer in the same system without changing the micro-tool. The machining performances are investigated with consideration of the surface topography and finishing depth. It is found that the more recast layer is removed when a higher ultrasonic amplitude, larger abrasive grain size, and lower tool feedrate are employed. Based on the preliminary experiments, the proper machining parameters are obtained and applied to the fabrication of micro-cavities. The machining results show that the surface quality is improved with the low surface roughness and absence of defect layer. Meanwhile, the high machining accuracy in the depth direction and processing efficiency are achieved. It is verified that the micro-EDM and micro-USM combined milling process is feasible for fabricating 3D micro-cavities in the ZrB2-SiC-graphite composite. [ABSTRACT FROM AUTHOR]

Ni-Al2O3 functionally graded materials (FGMs) have become important for high-temperature applications due to a continuous change in graded layers. However, the manufacturing process of Ni-Al2O3 FGMs with the traditional pulse power is a long process because the pulse power cannot real-timely adjust machining parameters to adapt the change of graded layers. This paper designed a real-time monitoring module and a parameter adjustment module, which can identify different graded layers and actively adjust machining parameters to adapt the change of graded layers. By means of the monitoring module, four major discharge states, normal, arc, insufficiency, and long pulse discharge state have been discriminated real-timely. The 70% Ni/30%Al2O3 layer and 30% Ni/70%Al2O3 layer have been distinguished based on the quantitative analysis of insufficiency and long pulse discharge waveforms. Multi-layers of Ni-Al2O3 FGMs are machined to validate the machining performance of the parameter adjustment module. Experiment results demonstrate that by adjusting the open voltage, the machining efficiency of 30% Ni/70%Al2O3 layer has been increased by six times, resulting in more time-efficient EDM process of Ni-Al2O3 FGMs. [ABSTRACT FROM AUTHOR]

We investigated the roles of deformation-induced ?-martensitic transformation on strain-controlled low-cycle fatigue (LCF) through crack-propagation analysis involving a notching technique that used a focused ion beam (FIB) setup on Fe–30Mn–4Si–2Al austenitic steel. Using the FIB notch, we separated the microstructure evolution into macroscopic cyclic deformation-induced and crack-propagation-induced microstructures. Following this, we clarified the fatigue crack-propagation-induced ?-martensitic transformation to decelerate crack propagation at a total strain range of 2%, obtaining an extraordinary LCF life of 1.1 × 104cycles. [ABSTRACT FROM AUTHOR]

The term maturity value (M) can be physically defined as the equivalent heating time (min) that is required for when culinary quality reaches a degree of being cooked properly at a specific reference temperature. The M value is a dynamic function which describes the change of the food quality being fully cooked and characterizes the degree of being fully cooked in cuisine. The termination maturity value (MT) is the M value reached at the time of being fully cooked. "Huohou" can be dynamically defined as the culinary operation minimizing the over-heated value when culinary quality reaches being fully cooked. Theoretic analysis and numerical simulation were studied in previous literature; however, whether the MT value exists or not, or whether its value is steady and merely relates to dynamic parameters and thermal history, has not been verified by experiments until now. As a result, it was necessary to measure MT value and its z value and analyze the influence factors under designed experimental conditions. A method to measure the MT value was established for the selected samples—pork loin. As the judgment of being fully cooked is subjective, sensory evaluation was used in cuisine. Firstly, samples with specific M values determined by the system of data acquisition and analysis on heat transfer and kinetics were prepared under different experimental conditions, i.e. size, shape, initial temperature, temperature and type of heating medium. In addition, a selection method of sensory evaluation difference tests was used to confirm the degree of being fully cooked in samples according to color, odor and texture, respectively. Under these conditions, the corresponding MT of color, odor and texture were regarded as the average M of being fully cooked samples. Based on the color, odor and texture weight given by experts, an integrated MT was acquired by the weighted average. Finally, a set of MT was obtained in the light of a different z value under the same experimental conditions. A corresponding z was the reasonable zM of cuisine being fully cooked when this set of MT standard deviation was minimum. The results indicated that an average IMT of A and B of pork loin were 0.51 and 0.31 min respectively, and MT values were proven to be invariable under different sizes, shapes, initial temperatures, temperatures and type of heating mediums, and could only be determined only by different pork loins. Since the zM value of M represents the sensitive degree of being fully cooked to heating; the lower the zM value, the easier being fully cooked is to be reached. The zM of meat cuisine M value was close to 10℃, which was inferred, approximately, from experimental results and the z value range of protein denaturation. For the same sourced pork lion, center points had different thermal histories and being fully cooked time had the same cooked quality when samples reached the same center MT. The above experimental result has provided evidence for the M value theory. M value is merely related to thermal history and zM; therefore, it can be widely used in cuisines especially suitable for the engineered calculated process of food being fully cooked. The above-mentioned results conformed to the definition of the MT value and the relevant parameters scope. To prove the M value theory thoroughly, much more in-depth and widespread experiments will be required. [ABSTRACT FROM AUTHOR]

With the popularization of the Internet, this technology has changed the form of information dissemination. The information will spread quickly when food product harm crisis happens, and the phenomenon that information of product-harm spills over is very common. This article is based on "Erustration - Misbehaving" research paradigm, combined with the information dissemination motivation theory, discusses that the fitness betw?een the consumers ad the crisis will promote consumers' dysfunctional customer behavior. The study found that the fitness between the consumers ad the crisis has significat effect on consumers' dysfunctional customer behavior, perceived social damage has a mediator effect betAveen fitness ad consumers' misbehavior, ad the moderating effect of consumers' agrssion tendency is significant, but not the emotional tendency. The theoretical contribution ad valuable implicanons of findings for communication of crisis management are discussed at last. [ABSTRACT FROM AUTHOR]

Degradation of phosphorene due to oxidation in air is extremely harmful to its performance in electronics and optoelectronics. Origin of this phenomenon is still debated and remains elusive. Through the state‐of‐the‐art first‐principles theoretical approach, GW method, it is believed that it is actually the vacancy–oxygen complex, formed by a single vacancy and an oxygen impurity nearby, that could lead to deep defect states in the bandgap and therefore deteriorate the performance of phosphorene, while isolated oxygen defects are electronically inactive. This information will be very helpful for protecting phosphorene from deterioration. Oxygen chemisorbed at perfect lattice site is electrically inactive, however, it chemisorbed around a single vacancy will give rise to deep energy level in the bandgap, the induced deep energy level in the bandgap due to the formation of vacancy–oxygen complex would deteriorate the performance of phosphorene. [ABSTRACT FROM AUTHOR]

Background: We aimed to assess the performance of the risk assessment questionnaire and fecal immunochemical test (FIT) in a population-based colorectal cancer (CRC) screening program to provide timely evidence for tailored screening strategies in China. Methods: This analysis was conducted using data from Beijing Cancer Screening Prospective Cohort Study (BCSPCS). A risk assessment questionnaire and FIT were selected as the primary screening methods, and participants with any positive results were referred to undergo a diagnostic colonoscopy. Results: From 2015 to 2020, 148,636 Beijing residents aged 40–69 years were invited from designated communities, with 147,807 finishing the risk assessment questionnaire and 115,606 (78.2%) completing the FIT. Among the 42,969 (29.1%) high-risk CRC participants, 23,824 (55.4%) underwent colonoscopy. One year after enrollment, all subjects were linked to the Beijing Cancer Registry (BCR) database and 241 cases of CRC were confirmed. The CRC incidence rate was 58.2/100,000 for the low-risk arm and 418.9/100,000 for the high-risk arm. For participants who underwent colonoscopy, 91 CRC cases were detected, with a detection rate of 91.9% and 63.7% of them were early-stage cases. Furthermore, the sensitivities of utilizing the risk assessment questionnaire alone, FIT alone, combined risk assessment questionnaire and FIT were 75.7%, 50.1%, and 95.1%, and the specificities were 75.3%, 87.3%, and 70.7%, respectively. Conclusion: The Beijing CRC screening program can effectively detect early-onset CRC; however, the compliance with colonoscopy still needs to be improved. [ABSTRACT FROM AUTHOR]

The present paper reported an one-pot synthesis of Co nanoparticles doped amino-graphene nanocomposites (Co-amino-Gr), involving in situ generation of Co nanoparticles (NPs). The simultaneous reduction of graphene oxide (GO) and Co 2+ to produce Co-amino-Gr had been achieved under mild reaction conditions using an environmentally benign reducing agent, glycine. By combining the merits of amino-Gr and the Co NPs, a highly sensitive electrochemical sensor was erected to detect baicalin based on the Co-amino-Gr nanocomposites. Under optimum conditions, the response peak currents were linear related with baicalin concentrations in the range of 1.0×10 −8 –8.0×10 −7 mol L −1 with a lower detection limit of 5.0×10 −9 mol L −1 (S/N=3). Additionally, the proposed method was used to detect baicalin in the medicinal capsules with satisfactory results. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the association between long-term exposure to fine particulate matter (PM 2.5) and its constituents (black carbon (BC), ammonium (NH 4 +), nitrate (NO 3 −), organic matter (OM), inorganic sulfate (SO 4 2−)) and incident female breast cancer in Beijing, China. Data from a prospective cohort comprising 85,504 women enrolled in the National Urban Cancer Screening Program in Beijing (2013–2019) and the Tracking Air Pollution in China dataset are used. Monthly exposures were aggregated to calculate 5-year average concentrations to indicate long-term exposure. Cox models and mixture exposure models (weighted quantile sum, quantile-based g-computation, and explanatory machine learning model) were employed to analyze the associations. Findings indicated increased levels of PM 2.5 and its constituents were associated with higher breast cancer risk, with hazard ratios per 1-μg/m3 increase of 1.02 (95% confidence interval (CI): 1.01, 1.03), 1.39 (95% CI: 1.16, 1.65), 1.28 (95% CI: 1.12, 1.46), 1.15 (95% CI: 1.05, 1.24), 1.05 (95% CI: 1.02, 1.08), and 1.15 (95% CI: 1.07, 1.23) for PM 2.5 , BC, NH 4 +, NO 3 −, OM, and SO 4 2−, respectively. Exposure-response curves demonstrated a monotonic risk increase without an evident threshold. Mixture exposure models highlighted BC and SO 4 2− as key factors, underscoring the importance of reducing emissions of these pollutants. [Display omitted] • Long-term exposure to PM 2.5 and its constituents was linked to higher female breast cancer risk in Beijing. • Key pollutants black carbon (BC) and sulfate (SO 4 2−) were identified as significant contributors to breast cancer risk. • Effective control measures are crucial in mitigating pollutants to reduce the risk of female breast cancer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rectangular defect can induce the mechanical degradation of the monolayer PtS 2. • Enlarged the defect can promote the mechanical recovery in the same direction. • Enlarged the defect may weaken the mechanical properties in the other direction. Using the classical molecular dynamics simulations, the mechanical properties of the PtS 2 monolayer with rectangular defects have been investigated. Particularly, a counterintuitive defect enlargement method to recover from defect-induced mechanical degradation has been explored. As the rectangular defects are enlarged along the zigzag direction, the uniaxial tension has been firstly applied in the same direction. It's found that the Young's modulus (Y s) increases slightly with the size of the defects. However, both the fracture strain and stress are increased obviously as the length of the rectangular defect increasing, indicating the recovery of the mechanical properties for the defective PtS 2 monolayer. And this degradation recovery could be attributed to the higher degree of geometric asymmetry when the defect being lengthened. Then, the mechanical properties of the defective PtS 2 monolayer under uniaxial tension in the armchair direction have also been studied. The calculations show that the Y s , fracture strain and stress decrease significantly as the rectangular defect enlarging. These results suggest even though the defect itself can induce the mechanical degradation, enlargement of the defect along a direction may promote the mechanical recovery in the same direction. [ABSTRACT FROM AUTHOR]

• Forest conversion significantly increased the ammonification rate. • Forest conversion decreased the nitrification and mineralization rates. • Forest conversion altered the function of the ectomycorrhizal community. • The ectomycorrhizal community is clearly linked to the altered N dynamics. • Some taxa of ectomycorrhizas are actively driving ecosystem processes. The conversion of natural forests to plantations affects soil carbon (C) and nitrogen (N) dynamics. However, the underlying microbial mechanisms of C and N dynamics caused by forest conversion, particularly the functional role of ectomycorrhizal (ECM) fungi, remain largely unknown. Here, we investigated the soil and root-associated fungal communities, soil and ECM root enzyme activities, and C and N mineralization rates in natural forests and plantations in the western Sichuan subalpine coniferous forest. Soil fungal and root ECM fungal communities were determined by high-throughput and Sanger sequencing, respectively. ECM root surface enzymes were used to assess fungal function, while soil enzymes, C and N mineralization, were used to evaluate soil function. Our results showed that clearing natural forests and converting them to plantations led to lower soil organic carbon (SOC), total nitrogen (TN), and pH, which drove changes in ECM and saprophytic (SAP) fungal communities. After forest conversion, the main difference in the fungal community was an increase in the ratio of ECM to SAP fungi. The most apparent change in the soil ECM fungal community is the shift of the dominant genera from Russula to Cortinarius and Piloderma. Subsequently, the function of the ECM fungal community was altered. The results indicated that the conversion of the natural forest to the plantation reduced ECM community β-glucosidase (βG), β-glucuronidase (βLU), N-acetyl-β-D-glucosaminidase (NAG), and acid phosphatase (AP) activities, and soil βG, NAG, and leucine aminopeptidase (LAP) activities. Among them, the activities of βG, βLU, and NAG in the ECM fungal community were significantly correlated with the activities of βG, βLU, and NAG in soil, respectively. Finally, we show that converting natural forests to plantations significantly increased the ammonification rate while decreasing the nitrification and mineralization rates. The close relationship between the relative abundance and diversity of the ECM fungal community, ECM communities and soil NAG, and N processes indicated that the changes in soil N dynamic after forest conversion were directly related to the changes in the ECM fungal community. Our results provide insight into soil C and N dynamics mechanisms resulting from forest conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Line defect can tune the mechanical properties of the monolayer PtS 2. • Within the small tilting angle range from 0 ° to 45 ° , the mechanical property is superior in the armchair direction. • In the large tilting angle range from 45 ° to 90 ° , the mechanical property is superior in the zigzag direction. By using the classical molecular dynamics simulations, the mechanical properties of the monolayer (ML) PtS 2 with the line defect of different tilting angles have been investigated. It has been found that mechanical properties including the fracture strain, fracture stress, toughness and Young's modulus in armchair and zigzag directions have been affected in very different levels. With the tilting angle being from 0 ° to 45 ° , the mechanical properties in armchair direction is more superior compared to those in the zigzag direction. On the contrary, the mechanical properties in the zigzag direction are much stronger as tilting angle increasing from 45 ° to 90 °. Tilting angle of 45 ° has been received unrivalled attention, where the ML PtS 2 with the line defect has presented isotropic mechanical properties in armchair and zigzag directions. The systematically parametric study on the line defect has been demonstrated that the tilting angle may change the isotropic property of the ML PtS 2 , resulting from its large length–width ratio and orientation of the line defect to the loading direction. The simulations in this paper shed light on a new possibility of fine-tuning mechanical properties and the realization of the isotropy-to-anisotropy of ML PtS 2 and other two-dimensional materials via line defect, which may expand the potential application these materials in the future nanometer devices. [ABSTRACT FROM AUTHOR]

Abstract: A series of mesostructured H3PW12O40–titania materials with two-dimensional hexagonal, three-dimensional cubic, and three-dimensional interconnected sponge-like pore geometries were developed by using a single step nonionic-surfactant-templating strategy combined with evaporation-induced self-assembly (EISA) or hydrothermal treatment technique. The mesostructure, morphology, porosity, optical absorption property as well as composition and structure of as-prepared materials were well-characterized. Subsequently, the materials were successfully applied to the degradation of an aqueous diethyl phthalate (a kind of endocrine disrupting chemical) under the simulated sunlight irradiation at λ >320nm and λ >400nm region, respectively, and special attention was paid to investigate the influences of the structural orderings, pore geometries, H3PW12O40 loadings as well as calcination temperature on the photocatalytic performance of the H3PW12O40–titania materials to the target reaction. [ABSTRACT FROM AUTHOR]

Abstract: A series of ordered mesoporous H3PW12O40/TiO2 composite materials with different H3PW12O40 loadings were prepared by an evaporation-induced self-assembly (EISA) route in the presence of a triblock copolymer surfactant. The materials exhibited 2D hexagonal p6mm symmetry and anatase phase structure with large BET surface area and uniform pore size as well as narrowed bandgap with respect to neat TiO2. The photocatalytic activity of the H3PW12O40/TiO2 materials was evaluated by the degradation of an aqueous dye methyl orange under solar simulating Xe lamp irradiation, and enhanced photocatalytic activity compared to pure TiO2 was obtained for the samples with suitable H3PW12O40 loadings. [Copyright &y& Elsevier]