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Corrosion of reinforcement bar caused by chloride ions diffusion is a crucial durability problem for concrete structures. Deoxyribonucleic acid (DNA) is a new type of corrosion inhibitor. Previous research has concentrated primarily on the influence of DNA on the corrosion of reinforcement bar caused by chloride salts in simulated concrete pore solution and cement-based materials, with scant attention to the chloride diffusion behavior of cement-based materials with DNA. In this work, the chloride diffusion behavior of cement-based materials with DNA was studied using chloride binding isotherm, chloride rapid migration (RCM), and natural diffusion tests. The composition, content, and morphology of the hydration products and pore structure were monitored using X-ray diffraction (XRD), thermogravimetry (TG), scanning electron microscopy (SEM), and mercury intrusion porosimetry (MIP) tests. The results show that DNA can improve the chloride-binding capacity and enhance the chloride diffusion resistance in cement-based materials. The lowest chloride migration coefficient and chloride diffusion coefficient were found in cement mortar with 4% by weight DNA, which were 45.58% and 42.36% lower than those of the reference group, respectively. DNA can stimulate the cement hydration reaction to produce more C-S-H gels and can increase the Ca/Si ratio of C-S-H. This is conducive to physical chloride adsorption. DNA can be combined with calcium ions to form insoluble aggregates that can fill the pore structure of mortar. Mortar with 4% by weight DNA maintained the lowest porosity, which effectively enhanced the chloride diffusion resistance. [ABSTRACT FROM AUTHOR]

This study aimed to examine the ability of classical test theory (CTT) and item response theory (IRT) scores assessed by Patient-Reported Outcomes Measurement Information System® (PROMIS®) measures to identify significant individual changes in the setting of clinical studies, using both simulated and empirical data. We used simulated data to compare the estimation of significant individual changes between CTT and IRT scores across different conditions and a clinical trial data set to verify the simulation results. We calculated reliable change indexes to estimate significant individual changes. For small true change, IRT scores showed a slightly higher rate of classifying change groups than CTT scores and were comparable with CTT scores for a shorter test length. Additionally, IRT scores were found to have a prominent advantage in the classification rates of change groups for medium to high true change over CTT scores. Such an advantage became prominent in a longer test length. The empirical data analysis results using an anchor-based approach further supported the above findings that IRT scores can more accurately classify participants into change groups than CTT scores. Given that IRT scores perform better, or at least comparably, in most conditions, we recommend using IRT scores to estimate significant individual changes and identify responders to treatment. This study provides evidence-based guidance in detecting individual changes based on CTT and IRT scores under various measurement conditions and leads to recommendations for identifying responders to treatment for participants in clinical trials. • Both classical test theory (CTT) and item response theory (IRT) have been used in scoring patient-reported outcome measures. • This study shows IRT scores have a prominent advantage in identifying significant individual changes in patient-reported outcomes over CTT scores. • This study provides evidence-based guidance in detecting individual changes based on CTT and IRT scores under various measurement conditions and leads to recommendations for identifying responders to treatment for participants in clinical trials. [ABSTRACT FROM AUTHOR]

Efficiency and stability are key factors determining the final cost of electricity that perovskite solar cells (PSCs) generate. To date, effective strategy to progress in achieving efficient and stable PSCs is still a difficult problem that researchers continue to explore. This study reports a useful way to improve the quality of SnO2 film by introducing potassium citrate (PC) into SnO2 nanoparticles solution. PC passivates interface defects between perovskite and SnO2 layers via the interactions of functional groups (K+, −COO−) in PC with undersaturated Pb and I ions in perovskite and Sn4+ in SnO2. The resultant photovoltaic (PV) device achieves a champion power conversion efficiency (PCE) of 22.79 %. The introduction of PC interface also significantly suppress the degradation of PSCs, by which 87.6 % of initial PCE is maintained after 2850 h storage in ambient environment. Moreover, the devices retained 95.5 % of initial PCE under 1‐sun continuous illumination for 1000 h. [ABSTRACT FROM AUTHOR]

A linking procedure establishes a "bridge" between the scores from different patient-reported outcome (PRO) instruments that measure similar constructs. After developing a linking relationship however, it is critical to evaluate whether this relationship can be generalized to different groups. Our study aims to validate a published crosswalk for score conversion between the Brief Symptom Inventory Depression subscale and the Patient-Reported Outcomes Measurement Information System Depression 8a using an independent sample. Data were from a sample of young men who have sex with men (MSM), which differs in terms of participant age, race, and ethnicity from the sample used to develop the existing crosswalk. The validity of the newly derived crosswalk was evaluated in terms of the correlation, mean difference and standard deviation between the observed and the linked scores. The two crosswalks were further compared to evaluate if the difference was within an acceptable range. More than half of the item parameters obtained from the two samples were found to overlap in their confidence intervals. Differences between each pair of scores in the two crosswalks was within three T-score points, well within the range of each crosswalk score's standard error. This study concludes that an existing crosswalk is replicable on a sample that differs from that used for crosswalk development, but future research should continue to examine the generalizability of the linked parameters and evaluate the reproducibility of this crosswalk to other populations. [ABSTRACT FROM AUTHOR]

Two-dimension MXene was applied in cement to fabricate MXene cement-based sensor used in structural health monitoring. The effect of MXene content on the piezoresistive performance of MXene cement-based composites (MCBC) was investigated. The fractional change in resistivity (FCR) under different loading rate, water content and failure load were also measured. Microanalysis results proves that MXene can construct electrical network in cement composites. The results demonstrated that the stress sensitivity has a maximum at 1.0 wt% MXene content. When loading rate increases, the sensitivities of composites decrease linearly, while the water content increases, the decrease of sensitivities is not completely linear. The relationship between compressive stress and fractional change in resistivity conforms to quadratic polynomial under failure load. [ABSTRACT FROM AUTHOR]

Electron transfer pathways have been verified as overriding regimes when peroxydisulfate (PDS) was activated by porous carbon. The incorporation of graphitic structure into carbon matrix was favorable to the rapid electron transfer, but excessive graphitization would deteriorate the specific surface area (SSA), weakening the catalytic performance. The reasonable trade-off between SSA and graphitization degree was necessary and challenging for the preparation of efficient carbon based PS-activators. Herein, a series of graphitic porous carbon with discrepant SSA and graphitic structure were fabricated. The incorporation of graphitization tracks into ultra-thin edges on porous carbon film was verified by multifarious structural characterization. After trade-off, the optimum catalyst exhibited superior catalytic performance with degradation rate constant (k obs) exceeding that of ungraphitized precursor by up to 16.0 times. Mechanistic investigations substantiated that the sufficient SSA of catalyst provided favorable conditions for its affinity towards PDS and sulfadiazine (SDZ), resulting in the formation of PDS* complexes and SDZ adsorption, while the appropriate graphitization degree ensured the reinforced electron transfer rate, which collectively accelerated SDZ oxidation through electron-transfer pathway. The multivariate linear regression model linking k obs to SSA and graphitization degree was established providing basis to construct efficient catalysts for PDS activation. [Display omitted] • A series of graphitic porous carbon were fabricated. • The sufficient SSA of catalyst accelerated its affinity to PDS and SDZ. • The appropriate graphitization degree ensured the reinforced electron transfer rate. • Reactive complexes were the foremost active species for catalytic oxidation. • The multivariate linear regression model was established. [ABSTRACT FROM AUTHOR]

This work investigated the effect of layered double hydroxides (LDHs) on the calcium leaching of cement pastes. The mass loss, porosity, leaching depth, compressive strength, and Vickers hardness were applied to evaluate the resistance to calcium leaching. Electrochemical impedance spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, and mercury intrusion porosimetry were conducted to investigate changes of cement hydrates and microstructure in cement pastes. The results demonstrate that the resistance to calcium leaching improves with increasing the content of LDHs and calcined LDHs (C-LDHs), and C-LDHs perform better resistance than LDHs. It is due to the filling effect of LDHs and C-LDHs in cement pastes. Additionally, they promote cement hydration, increasing the content of cement hydrates. As a result, LDHs and C-LDHs decrease the porosity and refine the pore structure, increasing the resistance to calcium leaching. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to link scores of the Revised Child Anxiety and Depression Scale short version (RCADS-25) to the metric of the PROMIS pediatric item banks Anxiety and Depressive Symptoms in a general Dutch population sample. Methods: The RCADS-25 and PROMIS pediatric item banks Anxiety and Depressive Symptoms were administered online to 2,893 Dutch children and adolescents aged 8–18. Assumptions for linking methods were checked. Linking was achieved by using three item response theory (IRT) and two equipercentile methods. For each method, the observed PROMIS metric scores were compared to the ones predicted from the RCADS-25 subscale scores using correlations, mean and SD of differences, and RMSD. Results: The assumptions for IRT-based and equipercentile linking were met. The IRT-based method using separate calibration with Stocking-Lord constants was considered the optimal choice for linking both RCADS-25 subscales to the PROMIS metric. Based on this Stocking-Lord approach, we created item parameters for RCADS-25 items and two crosswalk tables. Conclusion: The RCADS-25 item parameters and crosswalk tables presented in this study are sufficiently valid. Researchers can use these products to translate the RCADS-25 anxiety and depression subscales scores to the PROMIS metric in order to ensure comparability with the previous research. [ABSTRACT FROM AUTHOR]

Background: An increased focus on patient-reported outcome measures (PROMs) has led to a proliferation of these measures in orthopaedic surgery. Mandating a single PROM in clinical and research orthopaedics is not feasible given the breadth of data already collected with older measures and the emergence of psychometrically superior measures. Creating crosswalk tables for scores between measures allows providers to maintain control of measure choice. Furthermore, crosswalk tables permit providers to compare scores collected with older outcome measures with newly collected ones. Given the widespread use of the newer Patient-reported Outcome Measure Information System Physical Function (PROMIS PF) and the established Knee Outcome and Osteoarthritis Score (KOOS), it would be clinically useful to link these two measures.Question/purpose: Can the KOOS Function in Activities of Daily Living (ADL) subscale be robustly linked to the PROMIS PF to create a crosswalk table of equivalent scores that accurately reflects a patient's reported physical function level on both scales?Methods: We sought to establish a common standardized metric for collected responses to the PROMIS PF and the KOOS ADL to develop equations for converting a PROMIS PF score to a score for the KOOS-ADL subscale and vice versa. To do this, we performed a retrospective, observational study at two academic medical centers and two community hospitals in an urban and suburban healthcare system. Patients 18 years and older who underwent TKA were identified. Between January 2017 and July 2020, we treated 8165 patients with a TKA, 93% of whom had a diagnosis of primary osteoarthritis. Of those, we considered patients who had completed a full KOOS and PROMIS PF 10a on the same date as potentially eligible. Twenty-one percent (1708 of 8165) of patients were excluded because no PROMs were collected at any point, and another 67% (5454 of 8165) were excluded because they completed only one of the required PROMs, leaving 12% (1003 of 8165) for analysis here. PROMs were collected each time they visited the health system before and after their TKAs. Physical function was measured by the PROMIS PF version 1.0 SF 10a and KOOS ADL scale. Analyses to accurately create a crosswalk of equivalent scores between the measures were performed using the equipercentile linking method with both unsmoothed and log linear smoothed score distributions.Results: Crosswalks were created, and adequate validation results supported their validity; we also created tables to allow clinicians and clinician scientists to convert individual patients' scores easily. The mean difference between the observed PROMIS PF scores and the scores converted by the crosswalk from the KOOS-ADL scores was -0.08 ± 4.82. A sensitivity analysis was conducted, confirming the effectiveness of these crosswalks to link the scores of two measures from patients both before and after surgery.Conclusion: The PROMIS PF 10a can be robustly linked to the KOOS ADL measure. The developed crosswalk table can be used to convert PROMIS PF scores from KOOS ADL and vice versa.Clinical Relevance: The creation of a crosswalk table between the KOOS Function in ADL subscale and PROMIS PF allows clinicians and researchers to easily convert scores between the measures, thus permitting greater choice in PROM selection while preserving comparability between patient cohorts and PROM data collected from older outcome measures. Creating a crosswalk, or concordance table, between the two scales will facilitate this comparison, especially when pooling data for meta-analyses. [ABSTRACT FROM AUTHOR]

Background Context: When different health care providers use different patient-reported outcome (PRO) instruments, it is challenging to integrate findings that describe particular patient groups or to establish treatment effectiveness across studies. It is therefore critical to develop accurate ways to convert scores between various instruments for clinicians and researchers to make comparisons across health outcomes.Purpose: To develop a common metric so that scores on the Oswestry Disability Index (ODI) and scores on the PROMIS Physical Function can be converted interchangeably.Study Design/setting: Data were collected from a prospective study. A single-group linking design was used.Patient Sample: The study population included 9020 patients presented to an orthopedic spine clinic from November 2013 to March 2019.Outcome Measures: Patients completed the ODI and the PROMIS Pain Interference scale delivered by Computerized Adaptive Testing (CAT) at the same time prior to their visit with a spine clinician.Methods: Equipercentile linking methods based on log-linear smoothing approach and non-smoothing approach were used to establish a common metric across the two measures.Results: The two measures assess the similar contruct of pain. The correlation between the scores of the ODI and the PROMIS PI was 0.81. The standardized Root Expected Mean Square Difference (REMSD) values for gender, ethnic, and racial groups ranged from 3.55% to 4.81%. Hence, the assumptions for the equipercentile linking method were met. The crosswalk derived linked scores based on the log-linear smoothing method yielded small deviations (Δ = 0.09) from the observed scores. We then identified linked PROMIS-PI scores corresponding to the benchmark ODI scores for the five disability levels and for various categories of patients.Conclusions: This study is the first to create crosswalks to interchangeably convert scores between the ODI to the PROMIS-PI in a large population of spine patients using the equipercentile linking method. The results of this study provide confidence in the validity and usefulness of the derived crosswalks based on the equipercentile linking approach. The crosswalks are helpful for comparing new and old studies on the two measures and identifying benchmark scores for various diseases and disability levels. [ABSTRACT FROM AUTHOR]

Depression is a leading mental health concern across the U.S. and worldwide. There are myriad assessments to evaluate depressive symptoms, including the Edinburgh Postnatal Depression Scale (EPDS), which is widely used to evaluate women's pre- and postnatal depression but not as prevalent at other timepoints in adulthood, limiting its utility for longitudinal research. As part of the National Institutes of Health's (NIH) Environmental influences on Child Health Outcomes (ECHO) Research Program, the current study sought to develop a common metric so that scores on the EPDS can be converted to the standardized Patient-Reported Measurement Information System (PROMIS®) T-score metric. Drawing on data from the ECHO—Prenatal Alcohol in SIDS and Stillbirth cohort, this study used a single-group linking design, where 1,263 mothers completed the EPDS and PROMIS-Depression measures at the same time. Score linking was conducted using equipercentile and item response theory (IRT) methods. Results showed both linking methods provide robust, congruent results, and subgroup invariance held across age, race, ethnicity, education, and geographic location. The IRT-based unidimensional fixed-parameter calibration was selected due to its model simplicity, and a crosswalk table was established to convert scores from the EPDS to PROMIS T-scores. Overall, this study provides a way to aggregate data across various depression measures and timepoints, such that researchers and clinicians now have the ability to directly compare and combine EPDS data with PROMIS and other depression measures already score-linked to PROMIS. Public Significance Statement: This study provides a way for researchers and clinicians to combine and compare data from two commonly-used measures of adult depression. Using the crosswalk table generated through this research, scores on the Edinburgh Postnatal Depression Scale can now be converted to the same T-score metric as the Patient-Reported Outcome Measurement System (PROMIS®) Depression measure. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the agreement in substance use on both binary and ordinal scales between 3-month and 6-month recall periods with samples from different communities, demographic backgrounds, and HIV status. We administered the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) to 799 participants from three different North American cohorts focused on substance use and HIV. We conducted a within-person agreement analysis by calculating the agreement levels and Kappa statistic between data collected using the 3-month recall ASSIST and 6-month custom substance use surveys as well as different terminology for each substance in multiple cohorts. For all drugs studied, the agreement on the binary use or ordinal frequency of use metrics showed a high agreement level between 80.4% and 97.9% and an adequate adjusted kappa value between 0.61 and 0.96, suggesting substantial agreement. According to the agreement criteria we proposed, substance use data collected using different recall periods and with variation in drug names can be harmonized across cohorts. This study is the first to evaluate the feasibility of data harmonization of substance use by demonstrating high level of agreement between different recall periods in different cohorts. The results can inform data harmonization efforts in consortia where data are collected from cohorts using different questions and recall periods. • This study conducted an agreement analysis of substance use questions. • Self-reported substance use can be harmonized between different recall periods. • Self-reported substance use can be harmonized across cohorts. • An agreement criterion was proposed to determine the potential for data harmonization. [ABSTRACT FROM AUTHOR]

• This study applies the autoregressive latent trajectory model to probe longitudinal reading achievement in early elementary years and its relationships with classroom behavior and gender. • The autoregressive latent trajectory model performs better than the latent growth model and the autoregressive model. • Classroom behavior and gender status have a mix of positive and negative relationships with K-4 reading growth. Elementary students' ability to regulate classroom behavior is believed to play an important role in their reading ability. To date, there is some evidence articulating this relationship, but much of the research has not addressed how classroom behavior may predict the longitudinal reading achievement. The present study used data from the Early Childhood Longitudinal Study—Kindergarten Class of 2010–2011 to examine the associations of self-control, attentional focusing, and externalizing problem behaviors with reading development for elementary students from kindergarten through fourth grade. A combination of the latent growth model and the autoregressive model – the Autoregressive Latent Trajectory model is applied to describe children's increasing but later leveling off reading growth. Results from the Autoregressive Latent Trajectory model conditional on classroom behaviors show that they have a mix of positive and negative associations with reading growth. Further, a multigroup analysis reveals the gender differences in such associations. Implications for educators, researchers and policy makers are discussed. [ABSTRACT FROM AUTHOR]

In applications of item response theory (IRT) models, it is known that empirical violations of the local independence (LI) assumption can significantly bias parameter estimates. To address this issue, we propose a threshold-autoregressive item response theory (TAR-IRT) model that additionally accounts for order dependence among the item responses of each examinee. The TAR-IRT approach also defines a new family of IRT models for polytomous item responses under both unidimensional and multidimensional frameworks, with order-dependent effects between item responses and relevant dimensions. The feasibility of the proposed model was demonstrated by an empirical study using a polytomous response data. A simulation study for polytomous item responses with order effects of different magnitude in an education context shows that the TAR modeling framework could provide more accurate ability estimation than the partial credit model when order effect exists. [ABSTRACT FROM AUTHOR]

SnTe, as a lead-free analog of PbTe, shows limited thermoelectric performance because of the high hole concentration arising from intrinsic Sn vacancies and its high thermal conductivity. Herein, we show a significantly improved thermoelectric performance in p-type SnTe through NaBiTe2 alloying, by which carrier concentration optimization, band structure engineering, and thermal conductivity reduction are simultaneously realized. Band modification is confirmed by transport coefficient analysis based on the single parabolic band model. The low lattice thermal conductivity of SnTe−NaBiTe2 solid solutions is ascribed to point defect scattering. As a result, a zT value of ∼1.1 at 834 K is achieved in the sample with the nominal composition of (SnTe)0.96(NaBiTe2)0.04. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous carbonaceous material (CMs) were fabricated via various porogenic agents. • The increase in total pore volume of CMs facilitated the catalytic process. • Defect category in carbon skeleton induced by porogenic action was revealed. • Reactive complexes were the foremost active species for catalytic oxidation. • The inner-sphere interaction between CMs and peroxydisulfate was inferred. Porous carbonaceous materials (CMs) have been praised as superior candidates in activating persulfate for antibiotic wastewater decontamination. Whereas, as one of the frequently reported nonradical pathways, the formation mechanism of the reactive complexes and their correlation with physicochemical properties of CMs have not been comprehensively unveiled. Herein, a series of carbonaceous materials (CMs) with different specific surface area (SSA) and defect structures were fabricated by using KCl, MgCl 2 , KHCO 3 and K 2 C 2 O 4 as porogenic agents to activate peroxydisulfate (PDS) for sulfadiazine (SDZ) degradation. Results showed that the total pore volume of CMs exhibited a good linearity with degradation rate, attributing to the combined effect of SSA, defect degree and oxygen-containing functional groups according to multiple regression model. The reactive complexes (CM/PDS*) were proved as the foremost active species for SDZ oxidation via a suite of solid evidences. Compared with that after PS addition, the current direction was reversed after SDZ addition in i-t curves shedding light on the sharp enhanced potential of CM/PDS* and much low potential of SDZ. Furthermore, the inner-sphere CM/PDS* originating from the formation of new covalent bonds between CMs and PDS was inferred due to the poor dependence between electron-donating capacity and SDZ degradation result. The CM/PDS* with considerably higher potential can extract electron from SDZ based on the excellent positive relationship between electron-accepting capacity of CMs and SDZ degradation effect. This study advances the mechanistic comprehension of nonradical PDS activation, and provides a multiple regression model to predict degradation effects of carbon materials. [ABSTRACT FROM AUTHOR]

Sample pretreatment is important for chemical phase analysis of elements. In this study, the geological samples of the Laozuoshan gold mine are chosen to pretreat by ultrasonic centrifugation and cyclotron oscillation, and the content of gold in eight chemical phases (water-soluble, ion exchange and clay adsorption, organic matter bound, iron-manganese oxide bound, naked or seminaked, carbonate bound, sulfide bound, and insoluble silicate states) is determined by atomic absorption spectrometry. The results show that the gold content of water-soluble, ion exchange and clay adsorption, iron-manganese oxide, and naked or seminaked states in the rock and ore samples is low, and some samples have high gold content of insoluble silicate states in the two methods. However, the gold content of organic matter bound, carbonate bound, and sulfide bound states obtained by ultrasonic centrifugation and cyclotron oscillation methods is significantly different. According to the X-ray fluorescence spectrometry data and the actual geological condition, the result given by the cyclotron oscillation method is more reasonable. The gold content of sulfide bound state in sediment samples is the highest and consistent with the mineral information, which could be applied to preliminarily predict the rock and ore conditions in the corresponding mining areas. In contrast with ultrasonic centrifugation, the cyclotron oscillation method has the advantages of simplicity, high efficiency, practicality, and environmental protection, and it can be better used for the determination of gold chemical phase state in geological samples by atomic absorption spectrometry. [ABSTRACT FROM AUTHOR]

Cr2Ge2Te6-based compounds with a layered structure and high symmetry hold a great promise for thermoelectric applications. Our studies have been committed to improve their electrical properties considering the low power factor of only ∼0.23 mW/mK2 in pristine samples. In this work, various doping contents on the site that has less influence on the charge-conducting band have been investigated to enhance the power factor. The results show that Fe-doping is the most favorable among elements we applied. According to the first-principles calculation, the Fe doping on the Cr site leads to the increment of the density of states around the Fermi level. By tuning the carrier concentration via Fe doping, the peak power factor rises from 0.23 mW/mK2 to 0.37 mW/mK2 and zT rises from 0.3 to 0.4 at 830 K for Cr1.9Fe0.1Ge2Te6 along the pressing direction. These results shed lights for designing high performance thermoelectric materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous carbonaceous material (PCM) was made via different pretreatment strategies. • PCM made via ball milling for 60 min possessed the optimal PDS activation ability. • The sulfadiazine degradation positively correlated to defective degree of PCM. • C O groups were the active sites for sulfadiazine degradation by PCM/PDS system. Metal-free porous carbonaceous materials (PCM) are compelling for peroxydisulfate (PDS) activation. However, pore-creating processes are multifarious and their influences on PDS activation performance for organic degradation have not been elucidated. Herein, several PCM were synthesized via different pretreatment strategies, including manual grinding (MG), impregnation (IP) and ball milling (BM), to probe their influence on PDS activation efficiency. Therein, the PCM fabricated via BM for 60 min (BM60) was superior to all other varieties. The quantitative structure–activity relationship (QSAR) unveiled that BM accelerated the vertical expansion of turbostratic domains on PCM. The rate constant (k obs) of sulfadiazine (SDZ) degradation in PCM/PDS system positively correlated to the defective degree over PCM and C O content, indicating that the abundant defective structures over PCM contributed to enhance the PDS activation capacity by exposing more C O active sites. The C O groups can efficiently donate electrons to S 2 O 8 2− inducing the breakage of peroxy bond because of the brilliant electron donating capacities of BM60, which resulted in the generation of radicals. Robust mechanism studies by multiple electrochemical methods and in situ Raman technology suggested metastable intermediates (BM60/PDS*) with a higher redox potential was the predominant oxidant which can extract electrons from SDZ via a one-electron-transfer regime, while radicals were the secondary oxidants. This finding for the first time explicitly illuminated the electron transfer direction in the nonradical pathways of PDS activation for organics degradation by PCM and deepened the fundamental understanding on the electron-transfer pathway. [ABSTRACT FROM AUTHOR]

In this work, we successfully synthesized p -type Mg 2(1-x) Li 2x Si 0.4 Sn 0.6 (x = 0.00, 0.01, 0.03, 0.07, 0.09) samples using a home-made melt spinning system combined with spark plasma sintering. Compared with the samples prepared by a traditional method, the processing time is reduced from typically several days to less than one hour. It is found that the electrical conductivity rises rapidly with the increase of Li content owing to the enhanced carrier density, while the Seebeck coefficient decreases concomitantly to some extent. Meanwhile, Li doping dramatically reduces the thermal conductivity, leading to an enhanced figure of merit ZT ~ 0.58 at 760 K. [ABSTRACT FROM AUTHOR]

• Fe 2 MnGa alloys subject to rapid cooling and annealing treatment form magnetic isomers. • The magnetic phases in the samples are modulated by the degree of atomic disorder. • The ferromagnetic-antiferromagnetic transition and metamagnetic transitions are analyzed. • The possible atomic configuration and the path of atomic diffusion during annealing in the magnetic isomers are deduced. The magnetic properties of isomorphic heterogeneous γ -Fe 2 MnGa alloys were investigated by means of experiments and calculations. Fe 2 MnGa alloys subject to rapid cooling and annealing treatment show the same face-centered cubic structure at room temperature, but significantly different magnetic properties: the molecular magnetic moments are 2.11 and 4.49 μ B , while the Curie temperatures are 500 and 785 K. By combining the experimental and theoretical calculation results, it can be determined that disordered atomic occupation results in magnetic diversity in the same matrix structure. Rapid solidification introduces dislocated atoms, speculated to be due to partial interchange of Mn and Fe atoms with Ga atoms, which leads to an antiferromagnetic phase, while annealing can improve the degree of atomic order and transform the antiferromagnetic into a ferromagnetic phase. The change in the atomic occupation also leads to variation of the coercivity and a magnetic phase transition. [ABSTRACT FROM AUTHOR]

Sudan dyes are strictly prohibited from being added to edible products as carcinogens and tetracycline hydrochloride (TC) remaining in animal-derived food may cause harm to the human body. Therefore, it is necessary to establish a high-sensitivity, simple and convenient method for the detection of Sudan dyes and TC in foods for safety purposes. In this work, multifunctional blue fluorescent carbon dots (B-CDs) were prepared by a one-step hydrothermal synthesis using glucose as the carbon source. The results show that the fluorescence intensity of B-CDs was significantly affected by the acidity of the solution and can be quenched by Sudan I, IV and TC through selective studies. Interestingly, the fluorescence quenching intensities of B-CDs have a good linear relationship with the concentration of Sudan I and IV at pH = 3–7. The wide range of pH is beneficial to broaden the application of B-CDs in a practical samples analysis. The method has been successfully applied to real food samples of tomato paste, palm oil and honey, and the detection limits are 26.3 nM, 54.2 nM and 31.1 nM for Sudan I, Sudan IV and TC, respectively. This method integrates Sudan dyes and TC into the same multifunctional B-CDs, which shows that the sensor has a great potential in food safety detection. [ABSTRACT FROM AUTHOR]

A facile starch-assisted sol-gel method combined with freeze-drying technique has been developed to synthesize K-doped Li2 ZrO3 sorbents. SEM, TEM, and XRD techniques have been applied to characterize the morphology and structure of the synthesized K-doped Li2 ZrO3 samples. The CO2 capture-regeneration properties of the prepared K-doped Li2 ZrO3 sample were investigated using thermogravimetric analysis at different CO2 partial pressures. The K-doped Li2 ZrO3 synthesized using the starch-assisted sol-gel method combined with the freeze-drying technique shows excellent CO2 capture properties. At 823 K and a CO2 partial pressure of 0.25 bar, the uptake of CO2 reaches 22 wt% within 20 min, which is approximately 87% of the stoichiometric sorption capacity (25.3 wt%) of CO2 in the K-doped Li2 ZrO3 with a K: Li: Zr composition of 0.2:1.6:1 in molar ratio. Furthermore, the sorbent shows a good stability, confirmed using capture-regeneration cycles. [ABSTRACT FROM AUTHOR]

Abstract: K-doped Li2ZrO3 sorbents with excellent CO2 capture properties were synthesized via a citrate route. The CO2 capture–regeneration properties of these synthesized K-doped Li2ZrO3 sorbents were investigated by thermogravimetric analysis (TGA) at different temperatures and CO2 partial pressures. The synthesized K-doped Li2ZrO3 sorbents possess a better CO2 capture performance than reported Li2ZrO3-based ones, especially at low CO2 partial pressures. At 823K and a CO2 partial pressure of 0.25bar, the uptake of CO2 in the K-doped Li2ZrO3 with an optimized K:Li:Zr composition of 0.2:1.6:1 in molar ratio can reach 23wt.% within 15min. Furthermore, the sorbent displays a good stability, confirmed by CO2 capture–regeneration cycles. [Copyright &y& Elsevier]

Abstract: A novel C60 derivative-1,4-bis(pentafluorobenzyl)[60]-fullerene (C60(CH2C6F5)2) has been recently synthesized and can be utilized for high-performance organic photovoltaic devices. Its charge transport properties have been systemically investigated by band model and hopping model, respectively. Both models demonstrate that both electron and hole are favor of transporting, and C60(CH2C6F5)2 has the potential to be used as ambipolar transport material. The density of states, frontier molecular orbitals, and transfer integrals in main pathways show that it is the fullerene–fullerene face-to-face interaction, not C6F5–fullerene interaction determines the charge transport properties. [Copyright &y& Elsevier]

Abstract: A flow injection (FI) on-line preconcentration procedure for ultra-trace inorganic selenium was developed with detection by atomic fluorescence spectrometry. Selenium (IV) is co-precipitated with lanthanum hydroxide and collected on a PTFE beads packed column, the precipitate is afterwards dissolved with hydrochloric acid followed by hydride generation with reduction by tetrahydroborate. A thorough scrutiny was made for chemical variables and FI parameters. With a sampling volume of 3.4 ml, quantitative retention of selenium (IV) was obtained, along with an enrichment factor of 11 and a sampling frequency of 38 h−1. The detection limit, defined as 3 times the blank standard deviation (3σ), was 5 ng l−1. The precision was characterized by a RSD value of 1.2% (at the 0.5 μg l−1 level, n =11). The enrichment factor was further enhanced to 20 along with a detection limit of 3 ng l−1, with a sample loading volume of 6.8 ml. The procedure was validated with certified reference materials and biological samples. It was also applied to the speciation of inorganic selenium in surface waters. [Copyright &y& Elsevier]

At present, the direct gold determination in geological samples by inductively coupled plasma mass spectrometry (ICP-MS) is still an arduous challenge due to both spectral and background interferences. It is very important and necessary to study the pretreatment processes; therefore, the polyurethane foam treatment and sample digestion methods are explored and compared here. The experimental results showed that the gold adsorption rate of treated foam was significantly improved as the impurities in the foam were cleaned up, and the potential difference of the liquid membrane was increased. Meanwhile, the combination of the foam enrichment and thiourea desorption achieved the selective adsorption and desorption of gold ions, eliminated the interference of coexisting ions, and perfected the detection limits. Compared with the traditional electric heating plate digestion method, microwave digestion, a closed digestion method, had the advantages of less sample and reagent dosage, short time consumption, high degree of automation, thorough digestion, good security, and environmental friendliness and met the requirements of green chemistry development. The proposed microwave digestion-foam enrichment-thiourea desorption-ICP-MS determination method was applied to the gold test in soil samples of the actual gold mining area. It has the great potential as a routine laboratory procedure. [ABSTRACT FROM AUTHOR]

With the increasing attention to Computational Thinking (CT) in education, there has been a concomitant rise of needs and interest in investigating how to assess CT skills. This study systematically reviewed how CT has been assessed in the literature. We reviewed 96 journal articles to analyze specific CT assessments from four perspectives: educational context, assessment construct, assessment type, and reliability and validity evidence. Our review results indicate that (a) more CT assessments are needed for high school, college students, and teacher professional development programs, (b) most CT assessments focus on students' programming or computing skills, (c) traditional tests and performance assessments are often used to assess CT skills, and surveys are used to measure students' CT dispositions, and (d) more reliability and validity evidence needs to be collected and reported in future studies. This review identifies current research gaps and future directions to conceptualize and assess CT skills, and the findings are expected to be beneficial for researchers, curriculum designers, and instructors. • A review of current CT assessments about context, construct, assessment type, and psychometric evidence. • Fewer CT assessments were examined in high school, college, and professional development than in elementary school. • Most CT assessments focused on students' programming or computing skills. • Traditional and portfolio assessments were often used to assess CT, and surveys were used to measure CT dispositions. • Half of the studies reported reliability and validity evidence of their CT assessment. [ABSTRACT FROM AUTHOR]

Salient object detection (SOD), one of the most important applications in the field of computer vision, aims to extract the most visually appealing regions of scenes. However, the improvement of the accuracy of existing salient object detection in optical remote sensing images (ORSI‐SOD) is usually accompanied by an increase of network complexity, which affects the application of these models. Motivated by this, a novel lightweight edge‐supervised neural network for ORSI‐SOD is proposed, named CSFFNet. Specifically, the backbone (ResNet34) is first lightened by feature encoding module (FEM), building a lightweight subnet for feature extraction. Then, in the transformer‐based feature pyramid enhancement module (FPEM), the convolutional features obtained in the FEM are enhanced by long‐distance dependence to obtain multi‐scale features containing rich saliency cues. Based on this, the feature fusion module (FFM) is designed to capture cross‐scale long‐range dependencies and effectively fuse high‐level semantic information with low‐level detail information. Thus, the increase in network complexity due to multi‐level decoding is avoided. Finally, the segmentation results are optimized by using salient edges as auxiliary information, which effectively improves the contrast and completeness of the results. Experimental results on two public datasets demonstrate that the lightweight CSFFNet achieves competitive or even better performance compared with state‐of‐the‐art methods. [ABSTRACT FROM AUTHOR]

Computational thinking (CT) is believed to be a critical factor to facilitate STEM learning, and a vital learning objective itself. Therefore, researchers are continuing to explore effective ways to improve and assess it. Makerspaces feature various hands-on activities, which can attract students with diverse interests from different backgrounds. If well designed, scaffolded maker activities have the potential to improve students' CT skills and STEM learning. In this study, we explore ways to improve and assess physics and engineering integrated CT skills through developing maker activities and assessments, which are applicable in both informal and formal educational settings. Our paper presents our work on improving and assessing CT in maker activities with two primary goals. First, it introduces the maker activities and instruments we developed to improve and assess CT that are integrated in physics and engineering learning. Second, it presents the students' CT skill and disposition change from pretest to posttest in two summer academies with CT enhanced maker activities, which was respectively led by after school educators and formal educators in a public library. [ABSTRACT FROM AUTHOR]

Substance use severity is frequently measured using generic (i.e., non-drug specific) items. Yet, the measurement properties of these items must be evaluated for measurement invariance across inidividuals who use differing substances to ensure total scores can be compared across groups. This study used data from two independent samples (n 1 = 474; n 2 = 5183) and two measures of general substance use severity with generic items, the Patient Reported Outcomes Measurement Information System (PROMIS) Severity of Substance Use and DAST-10, to examine for differential item functioning (DIF) across substances (i.e., sedatives, opioids, amphetamines, cocaine, and cannabis). We utilized moderated nonlinear factor analysis to estimate DIF. Finally, we compared factor scores across estimation methods with and without accounting for DIF to examine the impact of DIF. A minority of items showed statistically significant DIF in each scale (Items with DIF: PROMIS Sample 1: 5/37; PROMIS Sample 2: 7/20; DAST-10 Sample 2: 3/10). Factor scores across scoring methods showed extremely high correlations (0.994 – 0.999), estimates of mean differences across substance groups did not vary considerably across scoring methods, but measurement differences were correlated with factor scores. These findings suggest that these two measures of substance use severity can be used across individuals using different substances. Factor scores appear similar across scoring methods and mean differences do not appear to be substantially biases. Measures with generic items may offer a parsimonious alternative to measures with drug specific items but more research is needed to evaluate the robustness of these findings. • Measures of substance use severity with generic items must be evaluated across drugs. • This study used moderated nonlinear factor analysis to evaluate such items. • Significant differential item functioning was identified across drug types. • Differential item functioning did not substantially impact factor scores. • Substance use severity can be measured across drug types using generic items.. [ABSTRACT FROM AUTHOR]

Background: Studies have reported mixed findings regarding the impact of the coronavirus disease 2019 (COVID-19) pandemic on pregnant women and birth outcomes. This study used a quasi-experimental design to account for potential confounding by sociodemographic characteristics. Methods: Data were drawn from 16 prenatal cohorts participating in the Environmental influences on Child Health Outcomes (ECHO) program. Women exposed to the pandemic (delivered between 12 March 2020 and 30 May 2021) (n = 501) were propensity-score matched on maternal age, race and ethnicity, and child assigned sex at birth with 501 women who delivered before 11 March 2020. Participants reported on perceived stress, depressive symptoms, sedentary behavior, and emotional support during pregnancy. Infant gestational age (GA) at birth and birthweight were gathered from medical record abstraction or maternal report. Results: After adjusting for propensity matching and covariates (maternal education, public assistance, employment status, prepregnancy body mass index), results showed a small effect of pandemic exposure on shorter GA at birth, but no effect on birthweight adjusted for GA. Women who were pregnant during the pandemic reported higher levels of prenatal stress and depressive symptoms, but neither mediated the association between pandemic exposure and GA. Sedentary behavior and emotional support were each associated with prenatal stress and depressive symptoms in opposite directions, but no moderation effects were revealed. Conclusions: There was no strong evidence for an association between pandemic exposure and adverse birth outcomes. Furthermore, results highlight the importance of reducing maternal sedentary behavior and encouraging emotional support for optimizing maternal health regardless of pandemic conditions. [ABSTRACT FROM AUTHOR]

To compare NFOSI-18 Disease Related Symptoms – Physical (DRS P), Total score, and side effect bother between maintenance rucaparib (600 mg twice daily) vs. placebo in the phase III ARIEL3 trial. ARIEL3 (NCT01968213) included patients with ovarian carcinoma who responded to second-line or later platinum-based chemotherapy. The NFOSI-18 DRS-P and Total scales were secondary endpoints. The NFOSI-18 contains a side effect impact item (GP5): "I am bothered by side effects of treatment." We compared treatment arms on change from baseline of DRS-P and Total scores using mixed models with repeated measures (MRMM). Time to first and confirmed deterioration of NFOSI-18 DRS-P and Total scales were analyzed using Cox regression. We also calculated the proportion of patients reporting moderate to high side effect bother on GP5. In the intention-to-treat (ITT) cohort, mean change from baseline favored the placebo. Compared to placebo, rucaparib was associated with higher risk of deterioration [e.g., 4-point deteriorator definition hazard ratio (HR): 1.85; 95% CI: 1.46, 2.36; median time to first deterioration on DRS P: 1.9 vs. 7.0 months]. Confirmed deterioration results resembled those for first deterioration. Proportions of patients reporting moderate/high side effect bother on GP5 fluctuated around 20% across treatment cycles. Results in BRCA mutant and homologous recombination deficient cohorts were generally similar to those from the ITT cohort. This placebo-controlled study in the maintenance therapy setting provides a unique view of the impact of PARP inhibition on the patient-reported outcomes that are commonly used in ovarian cancer clinical trials. Information regarding the adverse side effect impact of PARP inhibitors should be weighed against their clinical benefit. • This study used the NFOSI-18, which has more questions on relevant side effects of rucaparib than other QOL measures. • On the NFOSI-18, patients receiving rucaparib had a higher risk of deterioration than those receiving the placebo. • Patients receiving rucaparib reported high-moderate side effect bother on the FACT item GP5 approximately 20% of the time. [ABSTRACT FROM AUTHOR]

Ternary organic solar cells based on polymer donor PBDB-T, non-fullerene acceptor IDTCN-S and fullerene acceptor PC 71 BM can achieve enhanced charge transfer and improved the ternary blend film morphology. [Display omitted] • The enhanced charge transfer can be achieved via ternary blend strategy. • PC 71 BM as the third component can also effectively improve the blend morphology. • The ternary devices demonstrate an elevated PCE compared with two binary devices. Ternary organic solar cells (OSCs) based on one donor/one non-fullerene acceptor/one fullerene acceptor have been proven to be a promising method to boost photovoltaic performance. Herein, we report high-efficiency ternary OSCs fabricated with polymer donor PBDB-T, non-fullerene acceptor IDTCN-S and fullerene acceptor PC 71 BM, which possess complementary absorption spectra. The introduction of PC 71 BM as the third component into PBDB-T:IDTCN-S binary system can form cascade energy level alignment, which can facilitate charge transfer in the ternary blend films. Meanwhile, the addition of PC 71 BM also improve the ternary thin film morphology. As a result, ternary solar cells greatly boost the photovoltaic performance from 10.86% (PBDB-T:IDTCN-S) to 12.03%. Our research indicates that fullerene acceptor PC 71 BM is the efficiently third component for the construction of high-efficiency ternary OSCs. [ABSTRACT FROM AUTHOR]

Background: Soil salinization is a major abiotic environmental stress factor threatening crop production throughout the world. Salt stress drastically affects the growth, development, and grain yield of rice (Oryza sativa L.), and the improvement of rice tolerance to salt stress is a desirable approach for meeting increasing food demand. Receptor-like cytoplasmic kinases (RLCKs) play essential roles in plant growth, development and responses to environmental stresses. However, little is known about their functions in salt stress. Previous reports have demonstrated that overexpression of an RLCK gene SALT TOLERANCE KINASE (STK) enhances salt tolerance in rice, and that STK may regulate the expression of GST (Glutathione S-transferase) genes. Results: The expression of STK was rapidly induced by ABA. STK was highest expressed in the stem at the heading stage. STK was localized at the plasma membrane. Overexpression of STK in rice increased tolerance to salt stress and oxidative stress by increasing ROS scavenging ability and ABA sensitivity. In contrast, CRISPR/Cas9-mediated knockout of STK increased the sensitivity of rice to salt stress and oxidative stress. Transcriptome sequencing analysis suggested that STK increased the expression of GST genes (LOC_Os03g17480, LOC_Os10g38140 and LOC_Os10g38710) under salt stress. Reverse transcription quantitative PCR (RT-qPCR) suggested that four stress-related genes may be regulated by STK including OsABAR1, Os3BGlu6, OSBZ8 and OsSIK1. Conclusions: These findings suggest that STK plays a positive regulatory role in salt stress tolerance by inducing antioxidant defense and associated with the ABA signaling pathway in rice. [ABSTRACT FROM AUTHOR]

Metal-free porous biochars are popularly utilized as catalysts for peroxydisulfate (PDS) activation. The enhancement effect of PDS activation of porous biochars fabricated by employing both hard template and alkali metal activating agent has not been explored completely. In addition, the role of the inherent carbon defect in PDS activation has not been clearly elucidated. Hence, a series of carbonaceous catalysts were fabricated using a sole template (KCl), a sole activating agent (Na2S2O3) or a combination of template and activating agent (KCl/Na2S2O3, KCl/KHCO3, KCl/NaHCO3, and KCl/Na2C2O4), to systematically investigate the effect of specific surface area (SSA) and intrinsic defect of porous biochar on its PDS activation ability. The biochar synthesized by KCl and Na2S2O3 (SK-C) exhibited the optimum degradation performance. The SK-C was found to possess an interconnected hollow cage with three-dimensional mesh structure showing the largest surface area, pore volume and C-sp3 edge defect content among all the catalysts, which explained its paramount catalytic ability. The SSA and C-sp3 content together can determine the catalytic performance in a quantitative relationship. The single electron transfer pathway from SDZ to inner-sphere bound SK-C/PDS* was the protagonist of pollutant oxidation. The degradation intermediates were detected and recognized and their toxicities were evaluated. This study for the first time comprehensively identified the synergistic effect between the SSA and inherent defects on improving the catalytic performance of biochar for PDS activation to removal contaminants. Highlights: Several porous biochars with various surface area and defect degree were fabricated. These catalysts were used for peroxydisulfate activation to degrade sulfadiazine. The catalyst made by employing Na2S2O3 and KCl exhibited the optimum performance. The surface area and C-sp3 together determined quantitatively the catalytic effect. The single electron transfer from organic to inner-sphere catalyst/peroxodisulfate* was dominant. [ABSTRACT FROM AUTHOR]

To fundamentally explore the correlation between crop nutritional quality and mineral elements, specific tests and accurate analysis were carried out on all organs and root soil of watermelon (Citrullus lanatus). The results showed that the distribution patterns of nitrogen and phosphorus at watermelon maturity were similar, and the average nitrogen and phosphorus contents were in the orders of leaf and seed > stem, peel, root > pulp > root soil, and peel > seed > root, stem, leaf > root soil > pulp, respectively. From the perspective of element geochemistry, biophile and lithophile elements had the strongest correlation with nitrogen and phosphorus, and watermelon did not antagonize soil nitrogen and phosphorus uptake. The prediction model of nitrogen translocation factor in watermelon organs to total acid was established by partial least squares with R2 = 0.81. Significantly, when the isometric log-ratio of nitrogen to phosphorus in watermelon leaves was 1.97 to 2.19, the watermelon pulp showed better quality with total acid > 0.5%, total sugar > 5% and soluble solids > 10%. Therefore, the characterization of nitrogen and phosphorus in watermelon leaves can serve as a non-destructive analysis to predict watermelon fruit quality. [ABSTRACT FROM AUTHOR]

Hydropower has transitioned from base-load generation into an energy regulator in the hydro-wind-solar integrated systems, resulting in prolonged turbine operation under off-design conditions. Inspired by the new requirements of operation mode, an innovative Francis draft tube with inclined conical diffuser is presented to mitigate the pressure fluctuations and fatigue damage induced by flow instabilities. The design is optimized and comprehensively investigated to improve the operational flexibility. Computational fluid dynamics combined with design of experiments, artificial neural network and multi-objective optimization process lead to two optimal designs denoted as Opt-1 and Opt-2 from the Pareto fronts. Corresponding maximum pressure fluctuation amplitude is reduced by 15 % and 20 % compared to the traditional, respectively. An 81 % decrease of the fluctuating pressure recovery for the modified draft tube is obtained, leading to a steadier runner torque and consequently lower power swing. The asymmetric design of inclined daft tube is mainly targeted at the mitigation of the synchronous component as well as the attenuation of interaction between the swirling flow and elbow, accompanied with the mitigated energy of first-order vortex structure. The proposed innovative draft tube and optimization technique are found useful to broaden the operating range of hydraulic turbine in a computationally affordable way. • An innovative draft tube design allowing a wider operation of turbine is optimized. • An intelligent optimization framework is applied to the innovative draft tube. • Lower pressure fluctuations and power swing are achieved with optimization. • The mitigating mechanism of the optimized draft tube is explained. [ABSTRACT FROM AUTHOR]

Due to the complex characteristics of geological structures, identifying geochemical anomalies in valuable deposits using regional geochemical datasets of stream sediments is challenging. In this study, an effective combined method was proposed to solve the problem of anomaly identification in multibackground areas. First, samples were classified into different clusters through the k-means clustering method using major elements/minerals (such as SiO 2 and Na 2 O) that can reflect the lithology and were chosen as classification indicators. Considering the double restriction of the contour coefficient and lithological background, each sample within the same cluster was considered to have the same background. Then, the residual value between each sample and the mean data of adjacent samples within the same cluster was calculated, and the original data of each sample were replaced with the ratio (a new parameter defined as the residual contrast value) of the residual value and the anomaly threshold obtained for the corresponding cluster. Finally, geochemical maps and anomaly maps were generated using the residual contrast values. A practical example involving a regional geochemical dataset of stream sediments in Hunan, China, was examined in detail to clarify the procedure. Moreover, a comparative analysis through success rate curves of the percentage of deposits correctly determined was performed between the traditional method, singularity method and new combined method. The results showed that the anomalies identified by the proposed method were closely associated with known deposits, and the residual contrast value, which considers the effects of the lithological background, random error, and structural anomalies, could eliminate the influence of lithology and enhance weak anomalies. Moreover, the geological significance of this method is clear, and the calculation procedure is simple. Thus, this method could be applied for identifying regional geochemical anomalies in multibackground areas and could be used as a guide for new exploration targets. • Proposed an effective combined method for geochemical anomaly identification in multibackground areas. • Proposed a new parameter: residual contrast value • Lithological, random error, and structural anomaly are considered in the method. • Anomalies identified by this method has stronger association with the known deposits. • A comparative analysis was made through success rate curves of the percentage of deposits correctly determined among different methods. [ABSTRACT FROM AUTHOR]

Soil mercury (Hg) contamination has long been a problem that threatens the environment and organisms. Thus, exploring the migration and transformation of Hg from soil to vegetable is vital. In this study, different Hg solutions were employed in greenhouse experiments. The Hg contents in soil and vegetable samples were determined by inductively coupled plasma – mass spectrometry. The results showed that the Hg accumulation depended on its concentration and form. A greater accumulation of inorganic Hg was observed in the roots (2.2–27.4 mg/kg) than in the aerial parts (0.6–6.0 mg/kg). A similar trend was also found in the methyl mercury (MeHg) and ethyl mercury (EtHg) irrigated groups. The MeHg contents were 0.7–8.0 μg/kg in roots and 0.1–3.7 μg/kg in aerial parts. The EtHg concentrations were 0.5–3.3 μg/kg in roots and 0.3–1.1 μg/kg in aerial parts. The translocation factors of inorganic Hg and organic Hg for both vegetables in most treatments were less than 0.5, which suggested that Hg primarily accumulated in the roots. The biological concentration factors of inorganic Hg were less than 0.4, and those for MeHg and EtHg were between 0.4 and 0.95, which indicated that the vegetables were more likely to absorb organic Hg from the soil. The methylation of inorganic Hg occurred in the roots. The potential hazards of Hg on food safety and human health must be considered in regions with serious Hg pollution. [ABSTRACT FROM AUTHOR]

Objectives: MTHFR C677T and A1298C have been associated with the risk of preeclampsia (PE), but with conflicting results. We performed this meta-analysis to derive a more precise estimation of the association between MTHFR polymorphisms and PE. Study design: An electronic search of PubMed and Chinese Biomedicine database was conducted to select studies for meta-analysis. 54 case controlled studies containing MTHFR C677T and A1298C gene polymorphisms were chosen, and odds ratio (OR) with confidence interval (CI) was used to assess the strength of this association. Result: These studies evaluated 7398 cases and 11230 controls for MTHFR C677T. The overall results suggested that MTHFR C677T was associated with the risk of PE. (T vs. C: OR = 1.157, 95 % CI: 1.057-1.266, p=0.002; TT+CT vs. CC: OR=1.165, 95 % CI : 1.049-1.293, P = 0.004; TT vs. CT + CC: OR = 1.371, 95 % CI: 1.153-1.63, p < 0.001). We also evaluated 1103 cases and 988 controls for MTHFR A1298C but could not demonstrate an increased risk of PE for this polymorphism ( p=0.667). A symmetric funnel plot, the Egger's test ( p = 0.819) suggested a lack of publication bias. Conclusion: This meta-analysis supports the idea that MTHFR C677T genotype is associated with increased risk for PE, especially in the case of Asians and Caucasians. [ABSTRACT FROM AUTHOR]

Highlights: [•] Relationship between intermolecular interactions and charge transport properties. [•] Intermolecular π–π interactions have much effect on the hole transport. [•] Hydrogen bonding interactions are mainly responsible for the electron transport. [ABSTRACT FROM AUTHOR]

Human gut microbiota shows high inter-subject variations, but the actual spatial distribution and co-occurrence patterns of gut mucosa microbiota that occur within a healthy human instestinal tract remain poorly understood. In this study, we illustrated a model of this mucosa bacterial communities' biogeography, based on the largest data set so far, obtained via 454-pyrosequencing of bacterial 16S rDNAs associated with 77 matched biopsy tissue samples taken from terminal ileum, ileocecal valve, ascending colon, transverse colon, descending colon, sigmoid colon and rectum of 11 healthy adult subjects. Borrowing from macro-ecology, we used both Taylor's power law analysis and phylogeny-based beta-diversity metrics to uncover a highly heterogeneous distribution pattern of mucosa microbial inhabitants along the length of the intestinal tract. We then developed a spatial dispersion model with an R-squared value greater than 0.950 to map out the gut mucosa-associated flora's non-linear spatial distribution pattern for 51.60% of the 188 most abundant gut bacterial species. Furthermore, spatial co-occurring network analysis of mucosa microbial inhabitants together with occupancy (that is habitat generalists, specialists and opportunist) analyses implies that ecological relationships (both oppositional and symbiotic) between mucosa microbial inhabitants may be important contributors to the observed spatial heterogeneity of mucosa microbiota along the human intestine and may even potentially be associated with mutual cooperation within and functional stability of the gut ecosystem. [ABSTRACT FROM AUTHOR]

A simple low-molecular-mass organic gelator based on salicylaldehyde acylhydrazone had been synthesized and carefully studied. This gelator could form a thermo-reversible supramolecular organogel in many solvents by self-assembling them into nanofibers. Notably, it could even solidify crude oil floating on seawater. Moreover, the gelator was triggered to form a yellow metallogel with blue-green fluorescence by adding Y3+. In addition, it could act as an efficient fluorescent probe for the selective sensing of Y3+ in the solution containing water. The detection limit of Y3+ was 1.039 μM. Furthermore, test strips containing this compound were prepared, successfully used for on-site monitoring of Y3+ in water. [Display omitted] • A simple gelator based on salicylaldehyde acylhydrazone has been developed. • The compound exhibits excellent gel properties, including solidifying crude oil. • The compound can act as a highly selective fluorescent probe for Y3+. • The test strip containing the compound can detect Y3+ in water. [ABSTRACT FROM AUTHOR]

[Display omitted] • A D-D-type wide bandgap polymer PBDBP based on dibenzopyran unit are designed and synthesized. • The polymer PBDBP possesses a wide optical bandgap of 2.18 eV. • The PBDBP : Y6 based device can exhibit a high PCE of 11.43%. Pyran units as a six-membered heterocyclic nonaromatic containing one sp3 hybridized carbon and an oxygen have been widely employed to exploit donor and acceptor materials, and excellent power conversion efficiencies (PCEs) can be achieved for polymer solar cells (PSCs). In this work, a dibenzopyran (DBP) building block and a benzodithiophene (BDT) derivative as donor unit were utilized to successfully prepare a novel donor–donor (D-D)-type wide bandgap polymer PBDBP. The polymer PBDBP possesses an ultra-wide optical bandgap of 2.18 eV due to the weak intramolecular charge-transfer effect. Meanwhile, a low-lying HOMO energy of −5.41 eV is achieved, which is beneficial to realize a high V oc. Additionally, PBDBP also exhibits a complementary absorption with a narrow bandgap Y6 ranging from 300 to 950 nm, which can facilitate to improve light-harvesting ability for high J sc. Finally, PBDBP : Y6 based device exhibits a high PCE of 11.43 % (V oc = 0.89 V, J sc = 23.14 mA/cm2, and FF = 55.66 %). Our research indicates that the D-D-type polymer PBDBP based on dibenzopyran unit is a promising wide bandgap donor material for PSCs. [ABSTRACT FROM AUTHOR]

• A novel organic compound aminophylline (APL) is found to effectively passivate the electron transport layer. • APL can not only enhance crystal grain size, but also passivate the anti-site Pb (lead) defect. • The hydrogen bond formed by ethylenediamine (in APL) and iodide ions can assist the passivation of lead defects. Herein, we report highly efficient and stable triple cation perovskite solar cells (PSCs) with the structure of FTO/TiO 2 /perovskite/spiro-OMeTAD/Ag, in which we introduce aminophylline (APL) as an additive into the perovskite precursor solution to improve efficiency and stability. The APL additive results in increased device current density (J SC) (23.07–23.86 mA/cm2), fill factor (FF) (77.9–81.82%) and open-circuit voltage (V OC) (1.09–1.13 V), leading to an improved power conversion efficiency (PCE) of 22.11% compared to control devices (19.62%). It is worth noting that unpackaged devices employing the APL additive can remain 60% of their initial PCE in the air (at a humidity of 25–30%) after 100 days, whereas control devices merely retain less than 14% of the initial efficiency. [ABSTRACT FROM AUTHOR]

To provide technical support and theoretical guarantee for the prevention and control of soil heavy metal pollution, the main types of topsoil and parent material in Jilin Province were systematically collected, accurately tested by atomic fluorescence spectrometry and inductively coupled plasma mass spectrometry, and comprehensively evaluated through five indexes. By principal component analysis, it was initially judged that there were 2 or 3 major heavy metal sources in topsoil, which could be attributed to the parent material, soil-forming process, and/or anthropogenic factor. The pH of surface soil mainly depended on its parent material, and changed to a certain extent during its formation. The contents of heavy metals As, Hg, Cd, Cr, Cu, Ni, Pb, and Zn in surface soils were both significantly influenced by parent materials and soil-forming processes. Here the geo-accumulation index calculated by corresponding background value of parent material was more suitable for pollution assessment than the other four indexes, and the heavy metal contamination degree in each type of soil basically followed the order: Hg > Cd > Cu, Pb, Zn, As > Cr, Ni. Furthermore, the heavy metal contamination level in the types of soils was ranked as follows: cambisol, phaeozem > podzol, planosol > chernozem. The health risk assessment indicated that the soil in the study area had no significant carcinogenic or non-carcinogenic risks. Excluding the influence of parent material and soil-formation process, the comprehensive evaluation of soil heavy metal pollution will be more reasonable. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) based on nonfused ring electron acceptors (NFREAs) have shown great potential for future commercial applications due to their reduced synthesis complexity and low cost, and ternary strategy is a promising path for further boosting the development of NFREAs-based OSCs. Herein, two NFREAs FO-4Cl and FO-N with similar molecular structure are employed to fabricate high-performance ternary OSCs via combining a commonly used polymer donor PBDB-T. The PBDB-T:FO-4Cl and PBDB-T:FO-N binary devices can exhibit PCEs of 12.05% and 11.33%, respectively. Incorporating FO-N into the binary blend PBDB-T:FO-4Cl, the PBDB-T:FO-4Cl:FO-N ternary device can achieve a significantly improved PCE of 13.15% with a V oc of 0.87 V, a J sc of 20.59 mA/cm2 and an FF of 73.02%, which is 9% and 16% higher than the PBDB-T:FO-4Cl and PBDB-T:FO-N based binary devices, respectively. The enhanced J sc and FF can be ascribed to the enhanced photon harvesting, improved film morphology and high and balanced charge transport. Meanwhile, the V oc of ternary devices are gradually improved after the introduction of the high-lying LUMO component FO-N, which demonstrates that the two acceptors may form alloy state in the blend system. Our results demonstrate that ternary strategy is an effective path for further boosting the performance of NFREA-based OSCs by incorporating isogenous acceptors. [Display omitted] • Two nonfused ring electron acceptors FO-4Cl and FO-N are employed to fabricate ternary solar cells. • FO-N as ternary component could effectively improve blend morphology and charge mobilities. • The PBDB-T:FO-4Cl:FO-N ternary device can achieve a significantly enhanced PCE of 13.15%. [ABSTRACT FROM AUTHOR]

Maker activities are drawing increasing attention in the field of science, technology, engineering and mathematics (STEM) education. Researchers have developed various assessments for maker activities to examine students' learning outcomes. However, a systematic review of research on such assessments is lacking. To fill this gap, we reviewed empirical studies on maker-based assessments in education. We systematically examined 60 studies regarding the overall features of the maker activities, the learning outcomes that were measured, the assessment formats, and the psychometric evidence of the assessments. Our review results indicate that more than 20 types of maker platforms have been employed in the activities, with e-textiles and LilyPad Arduino being the most popular. Five types of assessment tools have been used prevalently to examine students' diverse learning outcomes, specifically artifact assessments, tests, surveys, interviews, and observations. Most assessments are used in STEM-related maker activities, especially technology-centric activities, to measure STEM-related learning outcomes. Only 15% of the studies provide psychometric evidence of reliability and validity for the assessments. Based on the findings, we provide suggestions for future research which include developing more low-tech maker activities for students in lower-grades and with lower technology proficiency. In addition, future studies should improve rubrics for artifact assessment and explore more assessment tools for non-STEM subjects. • More than 20 types of maker platforms have been employed in the maker activities. • Five types of assessment tools are prevalently used to examine students' diverse learning outcomes. • Most assessments were used in STEM-related maker activities to measure STEM-related learning outcomes. • Future studies should explore more assessment tools to measure all kinds of learning outcomes in maker activities. [ABSTRACT FROM AUTHOR]

The original version of this article unfortunately contained mistakes. [ABSTRACT FROM AUTHOR]