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Background Time perspective is strongly associated with depression. However, the characteristics and associations between trait and state time perspective in adolescents with depression remain unknown. Methods A total of 211 adolescents with depression (mean age: 14.60 ± 1.69 years) and 215 healthy controls (mean age: 14.66 ± 1.73 years) were selected and assessed using the Chinese version of the Zimbardo Time Perspective Inventory to quantify their trait time perspective. Thirty adolescents were randomly selected from each group to create nine-grid sandplay productions to assess their state time perspective. Results (1) Regarding the trait time perspective, depressed adolescents scored significantly higher on past negative, present fatalistic, present impulsive, and deviation-balanced time perspective (p < 0.001) and significantly lower on past positive and future (p < 0.05) compared to the control group. (2) In terms of state time perspective, depressed adolescents showed a significantly higher number of squares related to past negative, present negative, and future negative in their nine-grid sandplay productions compared to the control group (p < 0.01).Conversely, they had significantly fewer squares associated with past positive, present positive, future positive than the control group (p < 0.05). (3) Past negative, present fatalistic, and deviation from balanced time perspective traits were negatively correlated with positive state time perspective and positively correlated with negative state time perspective. Past positive and future traits were positively correlated with positive state time perspective and negatively correlated with negative state time perspective. Conclusion Adolescents with depression are characterized by dwelling on the past, having a severely negative attitude toward the past, being pessimistic about the future, and having a tendency to blame fate or external forces for their problems. In the future, standardized methods for measuring state time perspective should be further explored, as well as the effectiveness of the nine-grid sandplay, for improving time perspective in patients with depression.

Abstract Garnet-type Li6.5La3Zr1.5Ta0.5O12 (LLZO) is considered a promising solid electrolyte, but the surface degradation in air hinders its application for all-solid-state battery. Recent studies have mainly focused on the final products of the LLZO surface reactions due to lacking of powerful in situ characterization methods. Here, we use ambient pressure X-ray spectroscopies to in situ investigate the dynamical evolution of LLZO surface in different gas environments. The newly developed ambient pressure mapping of resonant Auger spectroscopy clearly distinguishes the lithium containing species, including LiOH, Li2O, Li2CO3 and lattice oxygen. The reaction of CO2 with LLZO to form Li2CO3 is found to be a thermodynamically favored self-limiting reaction. On the contrary, the reaction of H2O with LLZO lags behind that of CO2, but intensifies at high pressure. More interestingly, the results provide direct spectroscopic evidence for the existence of Li+/H+ exchange and reveal the importance of the initial layer formed on clean electrolyte surface in determining their air stability. This work demonstrates that the newly developed in situ technologies pave a new way to investigate the oxygen evolution and surface degradation mechanism in energy materials.

Porous Ti–6Al–4V alloys have been widely applied in industry, serving as structural or functional materials. However, the conventional method of producing porous Ti–6Al–4V by metal injection molding (MIM) with a space holder has several drawbacks, such as long debinding time, sintering furnace contamination, uncontrolled porosity and pore size, poor mechanical properties and process instability. This study presents a novel method of fabricating porous Ti–6Al–4V by MIM without space holder that can overcome these challenges. The porosity, average pore size, tensile strength, and compressive strength were studied by scanning electron microscope characterization, optical micrograph analysis, and mechanical testing. Flexible changes in porosity (17 %–74 %), pore size (14 μm–84 μm), and tensile strength (15 MPa–457 MPa) could be achieved by adjusting the powder size and sintering temperature. A higher porosity can be achieved as compared to the previous studies. The relationships among particle size, sintering temperature, porosity, and tensile strength are investigated by multiple regression models, which facilitate the tailored design of porous Ti–6Al–4V alloys for industrial applications and enhance the combination of experimental and theoretical methods in the design of porous alloys using MIM.

Abstract Background Disinfectant towelettes are increasingly being used as a means to prevent transmission of clinically important pathogens which could lead to healthcare-associated infections (HAIs). However, the efficacy of disinfectant towelette products when tested under realistic use conditions is understudied. A test model was designed to replicate realistic wiping conditions. The objective of this study was to determine the impact of varied contact time on disinfectant towelette efficacy under these conditions. Methods Five product types were tested against Staphylococcus aureus (ATCC 6538) and Pseudomonas aeruginosa (ATCC 15,442) at five contact times (30 s, one min, two min, three min, and 10 min) on hard, non-porous laminate templates to determine the impact of contact time on disinfectant towelette efficacy when tested under realistic use. Results Product type had a significant impact on the efficacy of disinfectant towelettes when tested under conditions reflective of realistic use. The effect of contact time was limited and no differences in efficacy were seen at a contact time of one min compared with the other contact times tested. Only one disinfectant towelette product achieved a mean 5-log reduction under the tested conditions. Conclusion Efficacy of disinfectant towelettes was primarily impacted by product type when applied in a model designed to replicate realistic use in which only a limited effect of contact time was observed. There is a need for further investigation into which factors have the greatest impact on disinfectant towelette efficacy when applied in clinical settings.

Abstract There has been an increase in Candida auris healthcare-associated infections, which result from cross-contamination from surfaces and equipment. In this study, we tested the efficacies of EPA-registered disinfectant towelettes products that are increasingly used for infection control against C. auris at a range of contact times following modifications to standard EPA protocol MB-33-00. Hydrogen peroxide (HP)-based disinfectant towelettes were more efficacious against C. auris than the quaternary ammonium chloride (QAC)-alcohol-based disinfectant towelettes irrespective of tested contact times. Thirty s contact time was significantly less effective in reducing C. auris compared to 1-, 2-, 3-, and 10-min contact times. However, there were no statistically significant differences in the level of disinfection among 1-min and longer contact times regardless of product chemistry. None of the products achieved a standard six-log10 reduction at any tested contact times. Overall, the HP-based disinfectant towelette was significantly more fungicidal than the QAC-alcohol-based disinfectant towelette. For all product types, 30 s contact time did not achieve the same level of disinfection as 1-min or longer contact times. Overall, disinfectant towelette efficacy is dependent upon product formulation and contact time.

Automatic crack segmentation plays an essential role in maintaining the structural health of buildings and infrastructure. Despite the success in fully supervised crack segmentation, the costly pixel-level annotation restricts its application, leading to increased exploration in weakly supervised crack segmentation (WSCS). However, WSCS methods inevitably bring in noisy pseudo-labels, which results in large fluctuations. To address this problem, we propose a novel confidence-aware co-training (CAC) framework for WSCS. This framework aims to iteratively refine pseudo-labels, facilitating the learning of a more robust segmentation model. Specifically, a co-training mechanism is designed and constructs two collaborative networks to learn uncertain crack pixels, from easy to hard. Moreover, the dynamic division strategy is designed to divide the pseudo-labels based on the crack confidence score. Among them, the high-confidence pseudo-labels are utilized to optimize the initialization parameters for the collaborative network, while low-confidence pseudo-labels enrich the diversity of crack samples. Extensive experiments conducted on the Crack500, DeepCrack, and CFD datasets demonstrate that the proposed CAC significantly outperforms other WSCS methods.

[Introduction] Integrated Gasification Combined Cycle (IGCC) power generation technology is a high-efficiency and low-carbon power generation technology. A waste heat boiler is one of the components of IGCC. This paper aims to study the off-design operating characteristics of waste heat boilers and improve the efficiency of integrated coal gasification combined cycle power generation technology. [Method] The working principle and heat and mass transfer principle of the waste heat boiler were mainly analyzed by MATLAB software to carry out programming calculations to explore the relationship between feed water temperature, feed water pressure, liquid-phase heat transfer coefficient, gas-phase heat transfer coefficient and heat absorption in waste heat boiler. [Result] The results show that when the liquid-phase heat transfer coefficient is in the range of 200～1 000 W/(m2·K) and the gas-phase heat transfer coefficient is in the range of 20～100 W/(m2·K), as if the feed water temperature increases from 30 ℃ to 100 ℃ or the feed water pressure increases, the heat absorption of the waste heat boiler decreases continuously. In case the feed water temperature is in the range of 30～100 ℃, when the liquid phase heat transfer coefficient increases from 200 W/(m2·K) to 1 000 W/(m2·K) or the gas phase heat transfer coefficient increases from 20 W/(m2·K) to 100 W/(m2·K), the heat absorption of the waste heat boiler increases continuously.[Conclusion] Under the condition that liquid-phase heat transfer coefficient and gas-phase heat transfer coefficient remain unchanged, the feed water temperature or pressure increases, and the heat absorption capacity of the waste heat boiler will decrease; While the feed water temperature and pressure remain unchanged, the liquid-phase heat transfer coefficient or gas-phase heat transfer coefficient increases, and the heat absorption capacity of the waste heat boiler will increase.

While water electrolysis devices represent a technology for renewable energy, there are few stable catalysts that survive the acidic conditions. Here, authors enhance acidic oxygen evolution by introducing strong Brønsted acid sites into RuO2 to accelerate bridging-oxygen-assisted deprotonation.

Psychological time reveals information about an individual’s psychological state and psychopathological traits and, thus, has become a new perspective through which the occurrence and development of depression can be examined. Psychological time includes time perception, time perspective, circadian rhythms, and passage of time. Patients with depression are characterized by inaccurate time interval estimation, habitual negative thoughts about the past and future, evening-type circadian rhythms, and slow passage of time. Habitual negative thoughts about the past and future and evening-type circadian rhythms influence the formation of depression, and poor time interval estimation and slow passage of time may result from depression. Further study is needed accurately exploring psychological time and influencing factors in patients with depression, and prospective cohort studies could further clarify this complex relationship. In addition, the study of psychological time has important implications for developing effective interventions to reduce depression.

Photocatalytic nonoxidative coupling of methane (NOCM) emerges as an appealing approach for the production of value-added C2 + hydrocarbons and hydrogen. Here the authors propose a heteroatom engineering strategy to prepare Pd single atoms loaded TiO2 for active and selective photocatalytic NOCM.

This paper presents a novel piezoelectric micromachined ultrasonic transducer (PMUT) with theoretical simulation, fabrication, and testing. Conventional methods using a PCB or an external horn to adjust the PMUT acoustic field angle are limited by the need for transducer size. To address this limitation, the stepped-tube (expanded tube) backside cavity PMUT has been proposed. The stepped-tube PMUT and the tube PMUT devices have the same membrane structure, and the acoustic impedance matching of the PMUT is optimized by modifying the boundary conditions of the back cavity structure. The acoustic comparison experiments show that the average output sound pressure of the stepped-tube backside cavity PMUT has increased by 17%, the half-power-beam-width (θ-3db) has been reduced from 55° to 30° with a reduction of 45%, and the side lobe level signal is reduced from 147 mV to 66 mV. In addition, this work is fabricated on an eight-inch wafer. The process is compatible with standard complementary metal oxide semiconductor (CMOS), conditions are stable, and the cost is controllable, plus it facilitates the batch process. These conclusions suggest that the stepped-tube backside cavity PMUT will bring new, effective, and reliable solutions to ranging applications.

Meaning in Life (MIL) is a protective factor that buffers the impact of COVID-19 epidemic on emotions. Our study aimed to explore whether photographic intervention based on MIL could increase Positive Affect (PA) and mitigate Negative Affect (NA), and whether Future Self-Continuity (FSC) functioned as a mediator between them. In this study, 90 college students were randomly divided into an intervention group or a control group. Participants in the intervention group were asked to take a photo and describe it every 2 days lasting 2 weeks. All the participants in the two groups were measured by the Meaning in Life Questionnaire, Positive and Negative Affect Scale, and Future Self-Continuity Scale before and after the intervention. The results showed that: (1) Before the intervention, there were no significant differences in baseline levels of MIL, PA and NA, and FSC between intervention and control groups. (2) In the intervention group, compared to pre-test, the scores of MIL, PA, and FSC of post-test increased significantly, and the score of NA of post-test decreased significantly. (3) After the intervention, the scores of MIL, PA, and FSC in the intervention group were significantly higher than those in the control group; NA score in the intervention group was significantly lower than that in the control group. (4) In terms of the difference score (post-test minus pre-test), FSC was a mediator between MIL and PA. Our study demonstrated that photographic intervention could effectively improve college students’ MIL, PA, and FSC while mitigating NA. Moreover, MIL could significantly enhance PA by the mediating role of FSC.

BackgroundDespite the number of empirical studies identifying the helpful factors correlated with beneficial psychotherapy outcomes, there is no validated scale that measures helpful therapeutic attitudes and interventions applied by therapists within the actual therapy process in China. In the current study, we developed the Helpful Therapeutic Attitudes and Interventions Scale (HTAIS) as an accessible client-rated instrument to measure useful interventions applied by the therapist during psychotherapy sessions.Materials and methodsBased on the results of previous literature and our prior psychotherapy process studies, a 40-item measure was initially designed. Two studies with a total of 2,780 Chinese participants who received psychotherapy were carried out to evaluate the structure, reliability, and validity of the developed scale.ResultsPrincipal component analysis yielded a three-component HTAIS containing 26 items. The scale included dimensions labeled “Empathy, respect and neutrality,” “Using techniques to solve practical issues,” and “In-depth exploration and expansion.” Confirmatory factor analysis showed the construct validity of the derived three components model. And the developed scale had high internal consistency and test-retest reliability. The scale scores of the HTAIS were positively correlated with those of the Working Alliance Scale and Session Rating Scale, as well as clients’ perceived therapy satisfaction, thus supporting its concurrent validity.ConclusionThe HTAIS allows an immediate examination, as experienced by the client, of the extent to which certain useful therapeutics interventions have been conducted during therapy and could help to improve the clinician’s subsequent therapy strategies. Future research is suggested to further validate the scale, especially to assess its psychometric properties in various populations with different clinical complaints.

The development of highly active and low-cost catalysts for use in oxygen reduction reaction (ORR) is crucial to many advanced and eco-friendly energy techniques. N-doped carbons are promising ORR catalysts. However, their performance is still limited. In this work, a zinc-mediated template synthesis strategy for the development of a highly active ORR catalyst with hierarchical porous structures was presented. The optimal catalyst exhibited high ORR performance in a 0.1 M KOH solution, with a half-wave potential of 0.89 V vs. RHE. Additionally, the catalyst exhibited excellent methanol tolerance and stability. After a 20,000 s continuous operation, no obvious performance decay was observed. When used as the air–electrode catalyst in a zinc–air battery (ZAB), it delivered an outstanding discharging performance, with peak power density and specific capacity as high as 196.3 mW cm−2 and 811.5 mAh gZn−1, respectively. Its high performance and stability endow it with potential in practical and commercial applications as a highly active ORR catalyst. Additionally, it is believed that the presented strategy can be applied to the rational design and fabrication of highly active and stable ORR catalysts for use in eco-friendly and future-oriented energy techniques.

Abstract Background Pre-wetted disinfectant wipes are increasingly being used in healthcare facilities to help address the risk of healthcare associated infections (HAIs). However, HAIs are still a major problem in the US with Clostridioides difficile being the most common cause, leading to approximately 12,800 deaths annually in the US. An underexplored risk when using disinfectant wipes is that they may cross-contaminate uncontaminated surfaces during the wiping process. The objective of this study was to determine the cross-contamination risk that pre-wetted disinfectant towelettes may pose when challenged with C. difficile spores. We hypothesized that although the tested disinfectant wipes had no sporicidal claims, they will reduce spore loads. We also hypothesized that hydrogen peroxide disinfectant towelettes would present a lower cross-contamination risk than quaternary ammonium products. Methods We evaluated the risk of cross-contamination when disinfectant wipes are challenged with C. difficile ATCC 43598 spores on Formica surfaces. A disinfectant wipe was used to wipe a Formica sheet inoculated with C. difficile. After the wiping process, we determined log10 CFU on previously uncontaminated pre-determined distances from the inoculation point and on the used wipes. Results We found that the disinfectant wipes transferred C. difficile spores from inoculated surfaces to previously uncontaminated surfaces. We also found that wipes physically removed C. difficile spores and that hydrogen peroxide disinfectants were more sporicidal than the quaternary ammonium disinfectants. Conclusion Regardless of the product type, all disinfectant wipes had some sporicidal effect but transferred C. difficile spores from contaminated to otherwise previously uncontaminated surfaces. Disinfectant wipes retain C. difficile spores during and after the wiping process.

Proton-coupled electron transfer (PCET) has been observed in chemical, energy, and biological transformation processes. Here we demonstrate that the rate of PCET and oxygen evolution reaction can be dramatically enhanced by tuning crystal orientation and the correlated proton diffusion.

Abstract Background Bacterial biofilms persistent on dry environmental surfaces in healthcare facilities play an important role in the occurrence of healthcare associated infections (HAI). Compared to wet surface biofilms and planktonic bacteria, dry surface biofilms (DSB) are more tolerant to disinfection. However, there is no official method for developing DSB for in vitro disinfectant efficacy testing. The objectives of this study were to (i) develop an in vitro model of DSB of S. aureus and P. aeruginosa for disinfectant efficacy testing and (ii) investigate the effect of drying times and temperatures on DSB development. We hypothesized that a minimum six log10 density of DSB could be achieved on glass coupons by desiccating wet surface biofilms near room temperatures. We also hypothesized that a DSB produced by the model in this study will be encased in extracellular polymeric substances (EPS). Methods S. aureus ATCC-6538 and P. aeruginosa ATCC-15442 wet surface biofilms were grown on glass coupons following EPA MLB SOP MB-19. A DSB model was developed by drying coupons in an incubator and viable bacteria were recovered following a modified version of EPA MLB SOP MB-20. Scanning electron microscopy was used to confirm the EPS presence on DSB. Results Overall, a minimum of six mean log10 densities of DSB for disinfectant efficacy were recovered per coupon after drying at different temperatures and drying times. Regardless of strain, temperature and dry time, 86% of coupons with DSB were confirmed to have EPS. Conclusion A rapid model for developing DSB with characteristic EPS was developed for disinfectant efficacy testing against DSB.

Abstract Background Disinfectant products are used frequently on environmental surfaces (e.g. medical equipment, countertops, patient beds) and patient care equipment within healthcare facilities. The purpose of this study was to assess the risk of cross-contamination of Staphylococcus aureus and Pseudomonas aeruginosa during and after disinfection of predetermined surface areas with ready-to-use (RTU) pre-wetted disinfectant towelettes. Methods This study tested six disinfectant towelette products against S. aureus ATCC CRM-6538 and P. aeruginosa strain ATCC-15442 on Formica surfaces. Each disinfectant was evaluated on a hard nonporous surface and efficacy was measured every 0.5 m2 using a modified version of EPA MLB SOP-MB-33 to study the risk of cross-contamination. Results We found that all of the wipes used in this study transferred S. aureus and P. aeruginosa from an inoculated surface to previously uncontaminated surfaces. Disinfectant towelettes with certain chemistries also retained a high level of viable bacteria after disinfection of the surface area. The cross-contamination risk also varied by product chemistry and bacterial strain. Conclusion Disinfectant wipes can cross-contaminate hard nonporous surfaces and retain viable bacterial cells post-disinfection, especially over larger surface areas. This highlights a need to further investigate the risk disinfectant wipes pose during and post-disinfection and guidance on maximum surface areas treated with a single towelette.

Abstract Doping perovskite oxide with different cations is used to improve its electro‐catalytic performance for various energy and environment devices. In this work, an activated lattice oxygen activity in Pr0.4Sr0.6CoxFe0.9−xNb0.1O3−δ (PSCxFN, x = 0, 0.2, 0.7) thin film model system by B‐site cation doping is reported. As Co doping level increases, PSCxFN thin films exhibit higher concentration of oxygen vacancies (Vo••) as revealed by X‐ray diffraction and synchrotron‐based X‐ray photoelectron spectroscopy. Density functional theory calculation results suggest that Co doping leads to more distortion in FeO octahedra and weaker metaloxygen bonds caused by the increase of antibonding state, thereby lowering Vo•• formation energy. As a consequence, PSCxFN thin film with higher Co‐doping level presents larger amount of exsolved particles on the surface. Both the facilitated Vo•• formation and B‐site cation exsolution lead to the enhanced hydrogen oxidation reaction (HOR) activity. Excessive Co doping until 70%, nevertheless, results in partial decomposition of thin film and degrades the stability. Pr0.4Sr0.6(Co0.2Fe0.7Nb0.1)O3 with moderate Co doping level displays both good HOR activity and stability. This work clarifies the critical role of B‐site cation doping in determining the Vo•• formation process, the surface activity, and structure stability of perovskite oxides.

Acetaminophen (APAP) toxicity is a common cause of hepatic failure, and the development of effective therapy is still urgently needed. Farnesoid X receptor (FXR), a member of the nuclear receptor superfamily, has been identified as a master gene for regulating enterohepatic metabolic homeostasis and has proven to be a promising drug target for various liver diseases. Through high-throughput chemical screening, the natural product 2-oxokolavenol was identified as a novel and selective FXR agonist. Further investigations revealed that 2-oxokolavenol exerts therapeutic efficacy against APAP-induced hepatocyte damage in an FXR-dependent manner. Mechanistically, 2-oxokolavenol forms two hydrogen bonds with M265 and Y369 of human FXR to compatibly fit into the ligand binding pocket of FXR, which potently leads to the recruitment of multiple co-regulators and selectively induces the transcriptional activity of FXR. Our findings thus not only reveal the direct target of natural product 2-oxokolavenol, but also provide a promising hit compound for the design of new FXR modulators with potential clinical value.

The aim of the present study was to investigate relationships among epidemic risk perception, perceived stress, mental health (depression and anxiety), future time perspective, and confidence in society during the novel coronavirus disease (COVID-19) pandemic in China. Especially, we wonder that whether perceived stress mediates associations between epidemic risk perception and mental health and that whether future time perspective and confidence in society moderate the link between perceived stress and mental health. This cross-sectional study was conducted among 693 Chinese adults aged 18–60 years. The results showed that epidemic risk perception was positively related to perceived stress, depression, and anxiety. The correlations between epidemic risk perception and depression and anxiety were reduced when perceived stress was included, suggesting that perceived stress mediated these relationships. Moreover, the boundary conditions for the associations among perceived stress, depression, and anxiety were found in the study. Specifically, positive future time perspective could buffer the negative effects of perceived stress on depression, and confidence in society could weaken the negative effects of perceived stress on anxiety. Based on these findings, practical guidance and theoretical implications are provided for the public to maintain mental health during COVID-19 pandemic. Limitations and future directions are also discussed.

Since the outbreak of coronavirus disease 2019 (COVID-19) in China, people have been exposed to a flood of media news related to the pandemic every day. Studies have shown that media news about public crisis events have a significant impact on individuals' depression. However, how and when the duration of attention to pandemic news predicts depression still remains an open question. This study established a moderated mediating model to investigate the relationship between the duration of attention to pandemic news and depression, the mediating effect of risk perception, and the moderating effect of future time perspective on the relationship. In early February 2020, 701 individuals from 29 provinces, autonomous regions, and municipalities across China were asked to self-report their duration of attention to pandemic news, level of depression, risk perception, and future time perspective during the COVID-19 outbreak. Results show that there is a significant positive correlation between the duration of attention to news on COVID-19 and depression; risk perception mediates the association between the duration of attention to pandemic news and depression; and future time perspective plays a moderating role between risk perception and depression. The findings of the present study provide theoretical implications and practically throw some light on alleviating the public's depression during pandemic periods. We highlight that the individual's hope for a better future, focusing on positive news, and time perspective balance during an epidemic disease are also beneficial to promoting positive emotion and reducing depression.

The key intermediate NH2-Ile-Thr(Bzl)-Asn-Cys(Bzl)-Pro-COOH of Atosiban was prepared from N-Boc-S-Bzl-cysteine by the stepwise lengthening of the chain according to the repetitive N,O-bis(trimethylsilyl)acetamide/N-hydroxysuccinimide ester (BSA/NHS) strategy. This synthetic route required no chromatography purification and can be readily performed, yielding a highly pure pentapeptide compound.

Vehicles carrying hazardous material (hazmat) are severe threats to the safety of highway transportation, and a model that can automatically recognize hazmat markers installed or attached on vehicles is essential for intelligent management systems. However, there is still no public dataset for benchmarking the task of hazmat marker detection. To this end, this paper releases a large-scale vehicle hazmat marker dataset named VisInt-VHM, which includes 10,000 images with a total of 20,023 hazmat markers captured under different environmental conditions from a real-world highway. Meanwhile, we provide an compact hazmat marker detection network named HMD-Net, which utilizes a revised lightweight backbone and is further compressed by channel pruning. As a consequence, the trained-model can be efficiently deployed on a resource-restricted edge device. Experimental results demonstrate that compared with some established methods such as YOLOv3, YOLOv4, their lightweight versions and popular lightweight models, HMD-Net can achieve a better trade-off between the detection accuracy and the inference speed.

A green and facile preparation was used to synthesize modified lignin (ML) from alkaline lignin by using hexamethylene diisocyanate (HDI) as the modifier and tetrahydrofuran as the solvent without a catalyst. Then, the as-synthesized ML was dispersed in hydroxy acrylic resin and used to prepare modified lignin-based polyurethane composites by using HDI trimer as the curing agent and dibutyltin dilauric acid as the catalyst at room temperature. Fourier transform infrared (FTIR) and elemental analysis confirmed that the main chemical in ML was lignin urethane when the amount of HDI was 0.2 g. The tensile strength of the modified lignin-based polyurethane (MLPU-0.2) film using ML-0.2 reached 12.07 MPa, which was improved by 23.2% and 68.3% compared with that of the pure polyurethane (PU) film (9.79 MPa) and lignin-based polyurethane (LPU) film prepared using unmodified lignin (7.17 MPa), respectively. After the addition of lignin or ML, the elongation at break of the polyurethane film increased. The water contact angle of MLPU-0.2 increased up to 96°, which was higher than that of PU (74°) and LPU (68°). The pencil hardness of MLPU-0.2 (3 H) was higher than that of PU (H) and LPU (2 H). Modified lignin-based polyurethane shows promise for marine anticorrosive coatings.

Abstract Background Antimicrobial disinfectants are used as primary treatment options against pathogens on surfaces in healthcare facilities to help prevent healthcare associated infections (HAIs). On many surfaces, pathogenic microorganisms exist as biofilms and form an extracellular matrix that protects them from the antimicrobial effects of disinfectants. Disinfectants are used as all-purpose antimicrobials though very few specifically make biofilm efficacy claims. The objective of this study was to evaluate the efficacy of eight registered disinfectants (six registered by the Environmental Protection Agency and two products registered in by the European Chemical Agency) with general bactericidal claims, but currently no biofilm efficacy claims, against Staphylococcus aureus ATTC-6538 and Pseudomonas aeruginosa ATCC-15442 biofilms. We hypothesized that hydrogen peroxide and sodium hypochlorite disinfectant products would be more effective than quaternary ammonium chlorides. Methods This study tested the bactericidal efficacy of eight registered disinfectant products against S. aureus ATCC-6538 and P. aeruginosa ATCC-15442 grown on glass coupons using a Center for Disease Control (CDC) biofilm reactor and EPA MLB SOP MB-19. Bactericidal efficacy was determined after treating coupons with disinfectants following standard EPA MLB SOP MB-20. Results Overall, sodium hypochlorite and hydrogen peroxide disinfectants had significantly higher bactericidal efficacies than quaternary ammonium chloride disinfectants. We also found that all tested disinfectants except for quaternary ammonium chloride disinfectants met and exceeded the EPA standard for bactericidal efficacy against biofilms. Conclusion In general, bactericidal efficacy against biofilms differed by active ingredient. The efficacies of sodium hypochlorite and hydrogen peroxide disinfectants did not vary between strains, but there were significant differences between strains treated with quaternary ammonium chloride disinfectants.

Abstract Background Disinfectant products are often used on environmental surfaces (e.g. countertops, patient beds) and patient care equipment in healthcare facilities to help prevent the transmission of healthcare-associated infections. Ready-to-use (RTU) disinfectants in the form of pre-wetted towelettes are increasingly popular among healthcare facilities. Currently, the EPA does not require disinfectant manufacturers to include a recommended maximum surface area per towelette on their product labels. The objective of this study was to investigate the efficacy of disinfectant towelette products on a hard non-porous surface across different coverage areas using a quantitative EPA method. We hypothesized that there would be significant differences in the efficacy of disinfectant towelette products, and that the greater surface area(s) wiped would result in reduced bactericidal efficacy. Methods This study tested ten disinfectant towelette products against Staphylococcus aureus strain ATCC CRM-6538 and Pseudomonas aeruginosa strain ATCC 15442 on Formica surfaces. Defined surface areas were wiped and the towelette weighed before and after wiping to determine the amount of liquid released. Bactericidal efficacy testing was also performed after wiping following standard EPA protocols. Results We found that disinfectant product, area of surface wiped, and strain impacted the bactericidal efficacy achieved. Disinfectant product type and area of surface wiped significantly impacted the percent of liquid released per ft2from the towelette. Conclusion Overall, bactericidal efficacy varied by towelette product, surface area wiped, and strain. This study also found that wiping larger surface areas may lead to decreased bactericidal efficacy. Further research is needed to test its implication.

Two-dimensional (2D) materials attract considerable interest due to their outstanding electronic and mechanical properties. Although extensive efforts have been made on seeking of new kinds of 2D materials, individual ones can hardly offer all required properties for practical applications in nanoelectronics and optoelectronics. To integrate the advantages of each individual component, in this work, we predict the structural and electromechanical properties of 2D van der Waals (vdW) heterobilayers constructed with single-layer Janus transition metal dichalcogenides and blue phosphorus (e.g., SMoSe/BlueP and SeMoS/BlueP) by means of density-functional theory (DFT) based calculations. The vdW interactions were carefully taken into account by employing the DFT-DF correction functional. It is found that the proposed vdW heterobilayers are dynamically stable with enhanced elastic moduli. The SeMoS/BlueP heterobilayer is shown as a type-I semiconductor with an indirect bandgap of 1.55 eV, and SMoSe/BlueP is also a type-I semiconductor with a slightly larger indirect bandgap of 1.76 eV. In addition, the piezoelectronic response of the heterobilayers was also carefully explored. In particular, the out-of-plane piezoelectric response of SeMoS/BlueP that is characterized by the piezoelectric coefficient e311(d311) gets enhanced compared to the Janus MoSSe monolayer. Our findings demonstrate a great potential for their applications in energy harvesting and sensors at the nanoscale.

Two dimensional materials are promising for electronic applications, which await the exploration of cooperative phenomena. Here, Liu et al. report switchable ferroelectric polarization in thin CuInP2S6film at room temperature, demonstrating good memory behaviour with on/off ratio of ∼100 based on two-dimensional ferroelectricity.

Lesson study (LS), a teacher-oriented, student-focused professional development (PD) approach that originated in Japan, has spread globally. However, existing literature on the implementation of LS and its effectiveness provides inconsistent results, suggesting a need to review current research on LS. With a focus on LS in mathematics education, we examined 75 recent LS studies using Lewis's (ZDM Mathematics Education 48:571-580, 2016. https://doi.org/10.1007/s11858-016-0792-x) framework to understand how LS is implemented and the pathways by which LS can impact teaching practice and student learning. We found that new developments have taken place in LS implementation, although challenges persist throughout its process. Regarding the implementation of LS, even though the examined LS studies generally contained four phases (study, plan, teach, and reflect), we found many LS lacked a research question, and the study of teaching materials was sometimes invisible. Across phases, studies shared a consensus that it is most critical to focus on students' thinking and learning, yet reported challenges in maintaining this focus. In addition, the role of knowledgeable others (KOs) was recognized but inconsistently understood. Collaboration was also widely reported as a challenge. Finally, there were large variations in LS duration, with some LS implementing overly brief cycles. Regarding LS impact, the literature has more frequently reported changes in teachers' knowledge and beliefs and less frequently in curriculum, learning community/professional norms, teaching practice, and student learning outcomes. The above challenges reflect a need for culturally relevant systemic support for developing sustainable and large-scale LS. We suggest future directions for continued research and practice improvement.

In order to realize the green and low-cost industrial production of acetylated lignin, this work proposes the heterogeneous reaction to acetylated lignin (ACAL) without catalysts and solvents at high temperature. The influence of reaction temperature and reaction time were investigated by IR, UV–vis, thermogravimetric analysis and water contact angle. Results showed that the optimum technological conditions were about 150 °C and 6 h. The degree of acetylation and the amount of residual phenolic hydroxyl groups of ACAL was 2.49 and 34.2%, respectively. Compared with conventional acetylated lignin, the ACAL had similar hydrophobicity with a water contact angle of 62.0°. The DTG peak of ACAL at about 200 °C reduced to 0.07 than the traditional acetylated lignin. The tensile strength and elongation of poly-lactic acid with 5 wt% ACAL increased to 64.03 MPa and 10.80%, respectively. ACAL revealed a great potential for mass production and applications owing to the eco-friendly and cost-effective modified method.

A simple and sensitive electrochemical sensor was developed for the detection of tracelevels of luteolin. The sensoris based on a novel type of chemically modified electrode: gold nanocage (AuNCs)-modified carbon ionic liquid electrode (CILE). To construct this electrochemical sensing platform for luteolin, CILE is initially prepared by using 1-hexylpyridinium hexafluorophosphate as the binder and then AuNCs are coated on the surface of CILE to fabricate AuNCs-modified CILE (AuNCs/CILE). Electrochemical studies have shown that AuNCs/CILE can exhibit enhanced electrocatalytic activity toward the redox reaction of luteolin, therefore, the redox peak current of luteolin can be greatly improved, resulting in the high sensitivity of the developed sensor. Under the optimal conditions, the oxidation peak currents of the sensor increase linearly with an increase in the luteolin concentration in a range from 1 to 1000 nM with a detection limit of 0.4 nM, which is lower than those of most reported electrochemical luteolin sensors. Moreover, the reproducibility, precision, selectivity, and stability of this sensor are excellent. Finally, the sensing system was applied to the analysis of luteolin-spiked drug samples and the recovery in all cases was 95.0–96.7%, indicating the potential application of this simple, facile, and sensitive sensing system in pharmaceutical analysis.

Reinforcement corrosion resulting from chloride attack is one major mechanism that compromises concrete durability. Numerical methods were commonly used for tackling Fick’s diffusion equations. In this paper, we developed a Crank-Nicolson based finite difference scheme suitable for circular concrete structures. Both a time-dependent surface chloride model and diffusivity were considered. The impact of an ideal sealer on chloride redistribution was further investigated. Results suggested that the chloride threshold depth in a concrete structure is greatly affected by the radius of curvature, environment severity, and diffusivity. For sealable concrete structures, both the sealer application timing and location are of great importance.

Piezoelectric semiconductors (PSCs) find widespread applications in smart electronic devices due to their unique combination of piezoelectric and semiconductive properties. With the increasing demand for smaller and more efficient electronic devices, the performance of their components needs to be carefully optimized, especially when they are scaled down to nanoscale sizes. Pioneering studies have demonstrated that surface elastic properties play a significant role in determining the mechanical performance of nanoscale materials and structures. Therefore, it is important to comprehensively investigate the effects of surface elasticity, including surface residual stress, surface membrane stiffness, and surface bending stiffness, on the electromechanical responses of a PSC nanoplate. Additionally, it is crucial to examine the influence of flexoelectricity at the nanoscale. Our results demonstrate that surface elastic properties predominantly impact mechanical performance, while the flexoelectric effect plays a more prominent role in electric field and redistribution of charge carriers. In particular, the significance of surface bending rigidity, which was often overlooked in previous literature, becomes pronounced when the thickness of a PSC nanoplate is less than 7 nm. Furthermore, the dependence of natural vibration frequency on surface elastic moduli, flexoelectricity, and size is, respectively, explored. The redistributions of electric potential and charge carriers across the cross section are also evidently affected. Our findings provide valuable insights for improving the performance of electronic devices that utilize nanoscale PSCs. [ABSTRACT FROM AUTHOR]