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AbstractCalibration refers to the statistical estimation of unknown model parameters in computer experiments, such that computer experiments can match underlying physical systems. This work develops a new calibration method for imperfect computer models, Sobolev calibration, which can rule out calibration parameters that generate overfitting calibrated functions. We prove that the Sobolev calibration enjoys desired theoretical properties including fast convergence rate, asymptotic normality and semiparametric efficiency. We also demonstrate an interesting property that the Sobolev calibration can bridge the gap between two influential methods: L2 calibration and Kennedy and O’Hagan’s calibration. In addition to exploring the deterministic physical experiments, we theoretically justify that our method can transfer to the case when the physical process is indeed a Gaussian process, which follows the original idea of Kennedy and O’Hagan’s. Numerical simulations as well as a real-world example illustrate the competitive performance of the proposed method. Supplementary materials for this article are available online, including a standardized description of the materials available for reproducing the work. [ABSTRACT FROM AUTHOR]

In recent years, organic-inorganic hybrid lead halide perovskite materials have attracted much attention in the world because of their excellent photoelectric properties, and have been successfully applied in many fields such as solar photovoltaic, photoelectric detection, electroluminescence and so on. At present, most of the device research focuses on perovskite polycrystalline materials, but perovskite single crystal materials have excellent properties such as lower defect state density, higher carrier mobility, longer carrier recombination lifetime, wider light absorption range and higher stability, which can effectively reduce the scattering loss during carrier transport and non-radiative recombination at the grain boundary, and inhibit the hysteresis effect caused by ion migration. Using perovskite single crystal thin film as the active layer of the device is expected to produce more efficient and stable perovskite photoelectric devices. At present, many preparation methods of perovskite single crystal films have been reported, mainly including solution-processed space-confined method, chemical vapor deposition method, top-down processing method, etc. Among them, solution-processed space-confined method is the most widely developed and applied. This paper focuses on the preparation of high-quality perovskite single crystal thin films by solution-processed space-confined method, and the research progress of perovskite single crystal thin films in photodetectors, solar cells, field effect transistors, light-emitting diodes and other related devices, and prospects the future development trend of perovskite single crystal thin films and photoelectric devices. [ABSTRACT FROM AUTHOR]

Organic material input can improve soil health and mitigate adverse environmental consequences; however, there is controversy regarding the promoting effects of organic material inputs on soil health due to a lack of quantitative information on the effects of different organic materials from agricultural sources on soil health. This study proposed a novel soil health evaluation method using tree-structured machine learning algorithms to quantitatively assess the effects of animal-sourced (AS) and plant-sourced organic materials (PS) on soil health. The results demonstrated that in the testing set, the two ensemble models, random forest regressor (RFR) and light gradient boosting machine regressor (LightGBMR), showed high coefficient of determination (R 2) of 0.879 and 0.877, respectively, and relative percent deviation (RPD) of 2.83 and 2.84, respectively (P < 0.001). Our findings indicated that the application of AS resulted in superior improvement of soil health for rice, wheat, and maize in comparison to PS. Compared with chemical fertilizer (CF), AS improved soil health indices (SHIs) for rice, wheat, and maize by 23.8–39.8%, PS improved SHIs for rice, wheat, and maize by 13.4–24.4%, and AS + PS improved SHIs for rice, wheat, and maize by 16.0–35.4% (P < 0.001). In addition, the positive effect of AS on SHIs was greater than that of PS. Compared with PS, the SHIs for rice, wheat, and maize increased by 7.34–14.9% for AS (P < 0.001). The reasonable nitrogen (N) application rates for rice, wheat, and maize were 262–290, 235–259, and 299–331 kg ha−1 year−1, respectively. Based on the positive feedback effects on soil health, the reasonable AS substitution rates for rice, wheat, and maize were 26.4–29.2%, 27.0–29.8%, and 29.6–32.8%, respectively. This study confirmed that organic materials improve soil health through optimized substitution, thus contributing to sustainable agricultural management and reducing adverse environmental impacts. [Display omitted] • A novel soil health assessment method using machine learning algorithms was explored. • Manure showed a better effect on soil health indices than plant-sourced materials. • Ideal manure substitution rates for rice, wheat, and maize were 27.8, 28.4, and 31.2%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tetracycline is effectively decontaminated by Mn 2 O 3 @ZIF-8 via PS activation. • OH, O 2 −, 1O 2 and reactive MnII (s) -S 2 O 8 2−* are involved tetracycline degradation. • Zn-O-Mn electron transport channel facilitates the electron transfer in PS activation. • MnII (s) on Mn 2 O 3 @ZIF-8 surface is the dominant sites for active species generation. Advanced oxidation processes (AOPs) based on persulfate (PS) activation is an extremely effective method to removal antibiotics in wastewater. In this process, endowing abundant active sites and rapid electron transfer channel over catalyst are two essential factors for high performance towards decontamination. Herein, a novel core–shell catalyst Mn 2 O 3 @ZIF-8 with large specific surface area was prepared to remove antibiotics via PS activation under visible light irradiation. Intriguingly, the removal efficiency of tetracycline (TC) by Mn 2 O 3 @ZIF-8 with optimal compound ratio was 3.2 times that of original Mn 2 O 3. The characterizations and density functional theory calculations proved that a Zn-O-Mn electron transfer channel was constructed in Mn 2 O 3 @ZIF-8 heterostructure, which greatly promoted electron transport and photogenerated electron-hole separation. In addition, the activation of PS and degradation of pollutants by Mn 2 O 3 @ZIF-8 was a highly surface-dependent reaction. The correlation between surface physicochemical properties and pollutant removal was further established to uncover the dominant active sites for PS activation. The quenching experiments and electron paramagnetic resonance (EPR) tests confirmed that PS was mainly activated by surface active MnII (s) and dissociated into reactive oxygen species OH, O 2 −, and 1O 2 , or formed reactive complexes MnII (s) -S 2 O 8 2−* to induce electron transfer and achieve TC oxidation. Besides, Mn 2 O 3 @ZIF-8 exhibited satisfactory removal of multiple pollutants and actual pharmaceutical wastewater as well as effective detoxification due to the coexistence of the above radicals and non-radicals pathways. The study provides novel insights into the design of high efficiency of Mn-based catalysts for antibiotic wastewater purification. [ABSTRACT FROM AUTHOR]

In this paper, a novel equilibrium-based form-finding approach for a mega-latticed structure is presented based on vector-based 3D graphic statics and the Combinatorial Equilibrium Modelling (CEM). This approach can be effectively applied to the conceptual design phase of the structures with various design objectives under conservative loads. It allows us to adjust the design parameters in real time during the design phase and to obtain the resultant forms immediately. Based on a certain selection strategy, the forms have a better state of internal membrane forces compared to the original spherical structure. An ANSYS Parameter Design Language (APDL)-based automatic geometric modelling method for mega-latticed structures with various surface forms is developed. The proposed method solves the problem that the existing modelling methods are only available for spherical structures. It is highly applicable for modelling mega-latticed structures with spherical, cylindrical, and other heterogeneous surfaces. Furthermore, a complete design workflow that combines the proposed form-finding approach (for conceptual design), the automatic geometric modelling method (for transformation), and the finite element method (for deepening design and analysis), is discussed. This paper provides a reference for the design of mega-latticed structures and similar truss-based spatial structures. • A new equilibrium-based form-finding approach for a mega-latticed structure is proposed. • An automatic geometric modelling method for mega-latticed structures is improved. • A design workflow combining the form-finding approach and finite element method is discussed. • A case study is performed to verify the validity of the whole structural design process. [ABSTRACT FROM AUTHOR]

The adverse effects of antimony (Sb) pollution on ecosystems and human health caused by its use, enrichment, and bioaccumulation have become global environmental problems, particularly in China. Based on a scientometric analysis of the research topics and evolution of Sb pollution, 210 peer-reviewed articles across 264 locations in China were selected to analyze Sb concentrations, changes, and risks in different environments (i.e., soil, sediment, and water). Substantially elevated concentrations were reported in the chosen environments throughout the studied literature, with approximately 36.6%, 41.3% and 20.8% of the soil, water and sediment sampling sites, respectively, exceeding the national and international guidelines. Although Sb concentrations were stable in water and sediment, those in soil slightly increased slightly over the past two decades. The majority of studies and the highest Sb concentrations were typically concentrated in Hunan, Guangxi, and Guizhou, where most Sb deposits and intensive mining and smelting activities are concentrated. A temporal analysis over three crucial periods of the Sb industry further indicated that Sb concentrations and pollution had increased in several provinces in recent years. The estimated risk quotient, using Monte Carlo simulations, indicated that species were markedly affected by Sb contamination, with 21.6% of events occurring in the high-risk category. The ingestion of contaminated soils posed the highest potential health risk to the population, with 47.9% of the events indicated to represent at least a low risk. Risks of water ingestion were estimated to exist in 4.9% of the simulated exposure events. More environmental campaigns for Sb pollution control are urgently needed, especially in Sb hotspots, to reduce environmental pressure and avoid direct and indirect hazards to organisms and populations. [ABSTRACT FROM AUTHOR]

Due to their high electronegativity and small atomic radius without undesirable steric hindrance, the incorporation of fluorine atoms onto a conjugated backbone has been proven to be a very effective way to tune the energy levels of organic semiconductors. In this paper, 5-fluorobenzo[c][1,2,5]thiadizole was adopted as the electron-deficient unit, thiophene and alkylthiophene as donor units, and further, thiophene and EDOT were taken as peripheral donor units, and one D–A–D and two D–π–A–π′–D fluorinated electrochromic polymer precursors were successfully synthesized via a Stille coupling reaction, namely F-BT, F-BT-Th, and F-BT-EDOT. Due to the elongation of the π-conjugated systems of precursors with the stronger electron-donating ability of the EDOT unit, the oxidation potential of the F-BT-EDOT precursor was further reduced to 0.56 V vs. Ag/AgCl accompanied by red-shifted electronic spectra. As-electropolymerized P(F-BT-EDOT) also showed favorable redox activity and excellent redox stability (<2.33% electroactivity loss after 1000 cycles). At the same time, the optical band gap of P(F-BT-EDOT) (1.37 eV) is much lower than that of P(F-BT-Th) and P(F-BT) (1.62 eV), and a stable reversible electrochromic change from dark green to dark blue was achieved with a fast response time. In the near-infrared region, P(F-BT-EDOT) shows intriguing overall electrochromic performance with a high optical contrast of up to 33% and a coloration efficiency of 196.3 cm2 C−1 at 1100 nm. It can be seen that the introduction of a strong electron-donor EDOT unit could bring about a new breakthrough in the electrochromic performance of 5-fluorobenzo[c][1,2,5]thiadizole-based fluorinated D–A polymers and enhancement in their stability, and it is expected to be applied in near-infrared electrochromic devices. [ABSTRACT FROM AUTHOR]

Chlorination has proved to be an efficient method in tuning energy levels and optoelectronic properties of organic semiconducting materials with cheaper synthesis and low-cost raw materials when compared with the fluorinated analogues. Herein, in this work, 5-chlorobenzo[c][1,2,5]thiadizole (Cl-BT) unit was chosen as a new acceptor unit to design two new D-A type electrochromic conjugated polymer: P(Cl-T) and P(Cl-EDOT). The electrochemical behavior and electrochromic performances of above-mentioned chlorinated polymers were studied by electrochemical polymerization techniques and spectroelectrochemistry. Thanks to the strong electron-withdrawing ability of Cl-BT unit and the strong electron-donating properties of EDOT unit, the resultant Cl-EDOT precursor could electropolymerize into high quality hybrid polymer films at lower potential (0.71 V vs. Ag/AgCl) with favorable redox activity and better redox stability. Spectroelectrochemistry shown that as-formed lower band gaps P(Cl-EDOT) exhibits reversible color-changing nature from pale blue to gray accompanied with the moderate optical contrast (13.9%), fast response time (0.6 s), and favorable coloration efficiency (126.4 cm2 C−1) in the NIR region that was measured from the kinetic studies. By optimizing the tested electrolyte and solution, its electrochromic performance is further improved (optical contrast: 25.6%, response time: 0.25 s, coloration efficiency: 275.9 C−1 cm2). The favorable redox stability and electrochromic performance of P(Cl-EDOT) make it a good candidate to construct electrochromic device, and Cl-BT unit should be a promising building block in designing high performance near infrared electrochromic materials. [Display omitted] • Two electrochromic precursor based on 5-chlorobenzo[c][1,2,5]thiadizole unit were synthesized by Stille coupling reaction. • Different donor brings different influence on the photophysical properties of the chlorinated precursors and its polymers. • The introduction of EDOT unit is beneficial for the preparation of better-quality chlorinated polymers. • P(Cl-EDOT) exhibit better redox activity and stability, and satisfied electrochromic performances. • Chlorinated benzothiadiazole could be a promising building blocks in constructing high performance D-A conjugated polymers. [ABSTRACT FROM AUTHOR]

Highly diverse exoenzymes mediate the energy flow from substrates to the multitrophic microbiota within the soil decomposer micro‐food web. Here, we used a "soil enzyme profile analysis" approach to establish a series of enzyme profile indices; those indices were hypothesized to reflect micro‐food web features. We systematically evaluated the shifts in enzyme profile indices in relation to the micro‐food web features in the restoration of an abandoned cropland to a natural area. We found that enzymatic C:N stoichiometry and decomposability index were significantly associated with substrate availability. Furthermore, the higher Shannon diversity index in the exoenzyme profile, especially for the C‐degrading hydrolase, corresponded to a greater microbiota community diversity. The increased complexity and stability of the exoenzyme network reflected similar changes with the micro‐food web networks. In addition, the gross activity of the enzyme profile as a parameter for soil multifunctionality, effectively predicted the substrate content, microbiota community size, diversity, and network complexity. Ultimately, the proposed enzymic channel index was closely associated with the traditional decomposition channel indices derived from microorganisms and nematodes. Our results showed that soil enzyme profile analysis reflected very well the decomposer food web features. Our study has important implications for projecting future climate change or anthropogenic disturbance impacts on soil decomposer micro‐food web features by using soil enzyme profile analysis. Highlights: Soil enzyme profile analysis for indicating decomposer micro‐food web features was first proposed.Diversity indication utilities for contrasting enzyme profiles were different.Protozoa channel index and enzymatic channel index were proposed. [ABSTRACT FROM AUTHOR]

The aggregation of transactive response deoxyribonucleic acid (DNA) binding protein of 43 kDa (TDP-43) into ubiquitin-positive inclusions is closely associated with amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration, and chronic traumatic encephalopathy. The 370–375 fragment of TDP-43 (370GNNSYS375, TDP-43 370-375), the amyloidogenic hexapeptides, can be prone to forming pathogenic amyloid fibrils with the characteristic of steric zippers. Previous experiments reported the ALS-associated mutation, serine 375 substituted by glycine (S375G) is linked to early onset disease and protein aggregation of TDP-43. Based on this, it is necessary to explore the underlying molecular mechanisms. By utilizing all-atom molecular dynamics (MD) simulations of 102 μs in total, we investigated the impact of S375G mutation on the conformational ensembles and oligomerization dynamics of TDP-43 370-375 peptides. Our replica exchange MD simulations show that S375G mutation could promote the unstructured conformation formation and induce peptides to form a loose packed oligomer, thus inhibiting the aggregation of TDP-43 370-375. Further analyses suggest that S375G mutation displays a reduction effect on the number of total hydrogen bonds and contacts among TDP-43 370-375 peptides. Hydrogen bonding and polar interactions among TDP-43 370-375 peptides, as well as Y374-Y374 π-π stacking interaction, are attenuated by S375G mutation. Additional microsecond MD simulations demonstrate that S375G mutation could prohibit the conformational conversion to β-structure-rich aggregates and possess an inhibitory effect on the oligomerization dynamics of TDP-43 370-375. This study offers for the first time of molecular insights into the S375G mutation affecting the aggregation of TDP-43 370-375 at the atomic level, and may open new avenues in the development of future site-specific mutation therapeutics. [Display omitted] • S375G mutation alters the distribution of free energy landscape of TDP-43 370-375 peptides. • S375G mutation possesses an inhibitory effect on the H-bonds formation. • S375G mutation results in a weaker Y374-Y374 π-π stacking interaction. • S375G mutation displays an inhibitory effect on the oligomerization dynamics of TDP-43 370-375. [ABSTRACT FROM AUTHOR]

• Two new D-π-A-π-D type monomers based on mono-chlorinated benzothiadiazole acceptor unit were synthesized. • Types of donor units caused significant effects on the photophysical properties of the chlorinated monomers and its polymers. • Lower oxidation potential of Cl-EDOT was beneficial for the chlorinated polymer's optoelectronic properties. • Lower band gaps P(Cl-EDOT) revealed favorable redox activity and stability, reversible electrochromic nature, and outstanding electrochromic performances. • Chlorinated benzothiadiazole could be a promising building block in designing high-performance D-A electrochromic polymers. Chlorinated benzothiadiazole (Cl-BT) unit, as a new type of electron-accepting building block with the advantages of easy large-scale synthesis in high yields, has been found to be very promising in designing high performance electroactive polymers with decent optoelectronic properties. Most recently, the Cl-BT unit-based D-A polymers have been applied in many organic electronic devices, but little attention was paid to their electrochromic applications. Herein, in this work, to further evaluate the electrochromic performances of the Cl-BT unit-based chlorinated D-A polymers, two new D-π-A-π-D type chlorinated monomers (Cl-Th and Cl-EDOT) which using mono-chlorinated benzothiadiazole unit as the acceptor unit and thiophene/3,4-ethylenedioxythiophene (EDOT) as the donor unit, was successfully synthesized by Stille coupling reaction and then yield their corresponding chlorinated polymer films (P(Cl-Th) and P(Cl-EDOT)) by electrochemical deposition method. Due to the stronger electron donor ability of EDOT unit, the monomer Cl-EDOT has red-shifted UV–Vis and emission spectra and more significant Stoke's shifts. The lower oxidation potential of Cl-EDOT was very beneficial for improving its resultant D-A chlorinated polymer's optoelectronic properties. As a result, as-formed lower band gap P(Cl-EDOT) (∼1.31 eV) showed reversible color change from the neutral dark green to the oxidized dark blue accompanied with outstanding electrochromic properties, including high optical contrast (24.3%), speedy response time (0.6 s), and high coloration efficiency (170.8 cm2/C), as well as favorable redox stability (70% activity retention after 1000 cycles). The favorable electrochromic performances and good optical stability of P(Cl-EDOT) make it a promising candidate in electrochromic devices. Overall, the chlorinated benzothiadiazole and its derivatives were promising building blocks in constructing high-performance D-A electrochromic polymers. [Display omitted] [ABSTRACT FROM AUTHOR]

Correction for 'Effects of polymer precursor conjugation length on the optoelectronic properties of fluorinated benzothiadiazole-based D–A systems' by Daize Mo et al., New J. Chem., 2024, https://doi.org/10.1039/d4nj00131a. [ABSTRACT FROM AUTHOR]

Colon cancer ranks among the most prevalent malignancies worldwide, trailing only lung and breast cancer in incidence. Despite the availability of numerous therapeutic strategies, the burden of new cases and fatalities remains high in countries undergoing socioeconomic transitions. Natural products offer promising avenues for developing more effective and less toxic anticancer agents, expanding the clinical arsenal. In this investigation, we isolated a triterpenoid, (21 S,23 R,24 R)-21,23-epoxy-24-hydroxy-21-methoxytirucalla-7,25-dien-3-one (EHMT), from the fruits of Melia azedarach L., which exhibited significant inhibitory activity against colon cancer cells while sparing normal cells. EHMT effectively curtailed colony formation and induced apoptosis and cell cycle arrest in the HCT116 cell line. Furthermore, EHMT prompted the generation of reactive oxygen species (ROS) and the depolarization of mitochondrial membrane potential. Notably, EHMT treatment triggered ROS-mediated cell apoptosis via activation of the JNK signaling pathway in HCT116 cells. Additionally, our findings extended to Caenorhabditis elegans , where EHMT induced ROS accumulation and apoptosis. Collectively, these findings position EHMT as a promising candidate for the development of anticancer agents in the treatment of colon cancer, offering new hope in the battle against this formidable disease. [Display omitted] (21 S ,23 R ,24 R)-21,23-epoxy-24-hydroxy-21-methoxytirucalla-7,25-dien-3-one (EHMT) was isolated from the fruit of M. azedarach L. EHMT caused ROS generation and induces apoptosis both in vivo and in vitro, triggered ROS-modulated cell apoptosis associated with JNK signaling pathway activation in colon cancer cells. • Natural products represent the biggest source of small molecules, providing a great potential to develop new anticancer agents. • EHMT, a novel anit-cancer triterpenoid isolated from Melia azedarach L. fruits, triggers ROS-modulated cell apoptosis and activates the JNK signaling pathway in colon cancer cells. • EHMT demonstrates a pronounced ability to inhibit the proliferation of colon cancer cells while exerting minimal impact on normal colon cells. • The findings in this study shed light on the potential of EHMT as a promising candidate for colon cancer therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • AgNWs@PB core–shell aerogel possessed simultaneously strong activity and high conductivity. • The aerogel-based wearable biosensor integrated with the microfluidic channel was highly sensitive to sweat uric acid. • The wearable biosensor presented a satisfactory accuracy in dynamic monitoring of sweat uric acid. Wearable sweat sensors have shown promise for noninvasive and dynamic monitoring of uric acid (UA), a key indicator in gout management. However, limited UA sensors are reported due to the low concentration in sweat and the inefficient sweat collection. Here, we presented a core–shell aerogel comprised by strongly conductive Ag nanowires (AgNWs) and highly active Prussian blue (PB) to continuously and accurately track sweat UA with the assistance of the microfluidic channel. The AgNWs@PB aerogel possessed a high intrinsic activity, a large active area and ample electron transfer pathways. In addition, the porous structure of the aerogel also provided abundant accessible channels, facilitating the diffusion of electrolyte and UA molecules. Therefore, the AgNWs@PB composite aerogel as a sensing unit demonstrated a high sensitivity of 50.6 µA mM−1 cm−2 towards UA detection, as well as a wide linear range. By integrating the microfluidic channel as a sweat collection unit, we tested the performance of the AgNWs@PB aerogel-based sensor in subjects before and after a purine-rich diet, the results of which were consistent with those detected by a commercial colorimetric assay kit. Furthermore, the as-prepared wearable sensor possessed a satisfactory accuracy in dynamic on-body monitoring of sweat UA within 12 h, which presented a good correlation with blood UA measured with a commercial UA meter. The personalized wearable sweat sensor has a great potential to provide the effective evidence for noninvasive UA control in future. [ABSTRACT FROM AUTHOR]

Biosensing assays involving antibody-antigen interactions have been widely applied in diagnostics and healthcare in virtue of their superior selectivity and sensitivity. However, antibodies typically suffer from complex and fragile functional structures, tedious preparation (resource-intensive and time-consuming), and large molecular size. As a result, the application of antibody-based biosensors tends to be constrained by short shelf-life and limited on-site/remote applicability. To date, AuNP-based colorimetric assays have been widely employed for point-of-care diagnostics in virtue of their user-friendly nature, low cost, chemical versability, and great potential in naked-eye detection. In this review, recent advances in the development of colorimetric assays based on gold nanoparticles (AuNPs) functionalized/combined with non-antibody recognition elements (e.g., liposomes, peptides, aptamers, other chemical molecules) for naked-eye detection of various analytes (e.g., enzymes, viruses, DNAs and bacteria) are discussed in terms of performances and characteristics. Additionally, challenges and future opportunities of these assays are explored. • Colorimetric assays based on gold nanoparticles functionalized/combined with non-antibody recognition elements are reviewed. • Naked-eye detection of different analytes by such assays are discussed. • Advantages, disadvantages, challenges and future opportunities of different colorimetric assays are explored. [ABSTRACT FROM AUTHOR]

Accurately describing the soil erosion process is crucial for improving the accuracy of existing simulation models of ephemeral gully erosion. However, a laboratory experimental strategy for simulating sediment distribution along slope lengths of an ephemeral gully is lacking. This limitation greatly hinders the development of simulation models for ephemeral gully erosion. In this study, we constructed six soil flumes with 12 m in length, 0.1 m in width, and 0.5 m in depth, which were filled with cultivated loess soils. Four flow rates (5.33, 10.67, 21.33, and 42.67 × 10−3 m3 s−1 m−1), four slope gradients (5°, 10°, 15°, and 20°), and six gully lengths (2, 4, 6, 8, 10 and 12 m) were adopted to perform a series of laboratory scouring experiments. The measured sediment concentrations at the outlet ranged from 23.39 kg m−3 to 534.60 kg m−3. The trend of exponential increase in sediment concentrations along slope lengths of an ephemeral gully was similar to that observed in a rill. According to the fitting equation, the maximum sediment concentrations (A e) ranged from 358.05 kg m−3 to 910.88 kg m−3. The attenuation coefficients (B e) indicated the rate of increase in sediment load with slope length, which ranged from 0.042 m−1 to 0.185 m−1. By combining the measured sediment loads along the slope length (8 m) with the sediment transport capacity, the sediment distribution along slope lengths of an ephemeral gully could be accurately quantified. Moreover, the results confirmed that a flume with a short slope length (4/6 m) could effectively determine the sediment distribution along slope lengths at gentle slope of 5° and 10°. However, a minimum length of 8 m was advisable at steep slope of 15° and 20°. In summary, our experimental strategy provides an efficient method for determining the sediment distribution along slope lengths of an ephemeral gully. [ABSTRACT FROM AUTHOR]

The expansion and intensification of human activities have resulted in excessive nitrogen (N) in rivers, causing worldwide concern. To effectively manage agricultural non-point source pollution and ensure a safe drinking water supply in watersheds, it is crucial to trace and quantify the primary sources and spatial distribution patterns of N. In response to the challenge of unclear sources and agricultural non-point source pollution, this study utilised the Bayesian isotope mixing model and Soil and Water Assessment Toolmodel to identify the dominant nitrate sources and transformation processes. These models were employed to quantify N retention by the mainstream and tributaries in the Bai River Basin, which directly impacts the safety of drinking water in Beijing. Total N (TN) concentrations in the Yunzhou Reservoir (4.22 ± 0.04 mg.L˗1) and Miyun Reservoir (2.88 ± 0.62 mg.L˗1) inlets in autumn and winter were V class (2 mg.L˗1) category as per GB 3838–2002 standards. This implies higher risks of eutrophication and algal blooms exceeding the standards at individual points and seasons in the Bai River. Fertilisers were the main nitrate source in the Bai River Basin, contributing 44.6% during the dry season and 62.9% during the wet season, suggesting that nitrate is more susceptible to leaching and runoff during rainy periods. Rainfall was not a major contributor, with only 3.2% and 2.9% originating from the Hebei and Beijing areas of the Bai River, respectively. Annually, the Bai River Basin exports loads of approximately 629.3 t.a˗1 of TN and 433.7 t.a˗1 of organic N (Org-N) from the Bai River Basin land to the river. The TN and Org-N loads at the final destination in the Miyun Reservoir were 521.3 t.a˗1 and 100.3 t.a˗1, respectively. Of the exported TN and Org-N, 17.16% and 76.87%, respectively, were retained in the river network. Consequently, N transformation occurred in the Bai River, with nitrification–denitrification being particularly dominant. Nitrification was more evident in the nitrate-enriched river. • Pollution risks persist in the Bai River during certain seasons. • Nitrification is more evident in the nitrate-enriched river. • Mainstream had a significant retention effect on the Organic N in the Bai River • Fertiliser is the dominant source of nitrate in the Bai River Basin [ABSTRACT FROM AUTHOR]

Exploring efficient catalyst and unveiling relevant intrinsic mechanism for pollutants control based on periodate (PI) activation is urgently required. Herein, an effective catalyst Cu 2 O with peculiar exposed facets and crystal edges was firstly developed to activate PI towards antibiotic wastewater degradation. Intriguingly, Cu 2 O nanocrystals with {100}+ {111} co-exposed facets together with their shared crystal edges exhibited the intrinsic high catalytic activity, and 88.90% of tetracycline (20 mg L−1) could be rapidly degraded within 5 min with k obs = 0.378 min−1, which outperformed the {100}, {110}, {111} solely exposed ones or {100}+ {110}, {100}+ {110}+ {111} co-exposed ones. A comprehensive mechanism study revealed that the crystal edges of {100}/{111} in Cu 2 O nanocrystals are conducive to better electron transfer, charge separation, and PI adsorption properties, thus triggering highly efficient PI activation over other crystal edges exposed nanocrystals. Besides, {100}/{111} crystal edges in Cu 2 O crystal made the PI activation-induced antibiotic degradation change from the non-radical/radical mixed reaction to 1O 2 (75.71%) dominated nonradical reaction. This work provides systematical insights into constructing effective catalysts for wastewater treatment via structure engineering. [Display omitted] ● A series of Cu 2 O with different facets and crystal edges is synthesized. ● Cu 2 O with {100}+ {111} co-exposed facets exhibits the prominent PI activation. ● {100}/{111} edges makes for electron transfer, charge separation, and PI adsorption. ● {100}/{111} edges switch the active species from mixed radical/non-radical to 1O 2. [ABSTRACT FROM AUTHOR]

Inhibiting tau protein aggregation has become a prospective avenue for the therapeutic development of tauopathies. The third microtubule-binding repeat (R3) domain of tau is confirmed as the most aggregation-favorable fragment of the whole protein. As dimerization is the first step of the aggregation of tau into amyloid fibrils, impeding the dimerization of the R3 domain is critical to prevent the full-length tau aggregation. Natural polyphenol small molecules epigallocatechin gallate (EGCG), quercetin (QE) and gallic acid (GA) are proven to inhibit the aggregation of the full-length recombinant tau (For EGCG and QE) or the R3 domain (For GA) of tau in vitro. However, the underlying molecular mechanisms of the inhibitive effects on the R3 domain of tau remain largely unknown. In this study, we conducted numerous all-atom molecular dynamics simulations on R3 dimers with and without EGCG, QE or GA, respectively. The results reveal that all three molecules can effectively decrease the β structure composition of the R3 dimer, induce the dimer to adopt loosely-packed conformations, and weaken interchain interactions, thus impeding the dimerization of the R3 peptide chains. The specific preferentially binding sites for the three molecules exhibit similarities and differences. Hydrophobic, π-π stacking and hydrogen-bonding interactions collectively drive EGCG, QE and GA respectively binding on the R3 dimer, while QE also binds with the dimer through cation-π interaction. Given the incurable nature of tauopathies hitherto, our research provides helpful knowledge for the development of drugs to treat tauopathies. [Display omitted] • EGCG, QE and GA can inhibit the formation of β-sheet of the R3 domain of tau. • EGCG, QE and GA can impede the interchain interaction of the R3 peptide chains. • Hydrophobic, π-π stacking and hydrogen-bonding interactions are the common driving forces inducing EGCG, QE and GA binding on the R3 dimer. • EGCG displays stronger interaction on the R3 dimer than QE and GA. [ABSTRACT FROM AUTHOR]

The typical resolution for long-term wind speed records that are publicly available in China is daily, this is too coarse for a sound analytical simulation of snowdrift on building roofs. Take Harbin, China as an example, an algorithm was proposed in this study to address this issue, where the commonly-used 2-parameter Weibull distribution was applied to fit the distribution of 10-min mean wind speed. A parameter estimation method, which combines the method of moment and cumulative probability, was proposed to estimate the parameters of Weibull distribution using very limited information on wind speed. The fitted probability model was validated using high-resolution wind speed data by comparing the snowdrift estimated by the modeled wind speed and that estimated by the actual wind speed. Finally, an analytical simulation of snowdrift on a flat roof was carried out to illustrate the application of the proposed model, and the probabilistic characteristic of the derived ground-to-roof conversion factors for snow loads were analyzed. It is indicated that the proposed model is easy to implement and provides a good estimation of the snowdrift on building roofs, and the derived conversion factors could be satisfactorily modeled using a Generalized Extreme Value (GEV) distribution or a normal distribution. • An algorithm was proposed to incorporate very limited wind information into the analytical simulation of roof snow load. • The proposed algorithm is the first of its kind. • An analytical simulation of snowdrifts on a flat roof was carried out using the proposed algorithm. • Probabilistic characteristics of the derived ground-to-roof conversion factors were analyzed. [ABSTRACT FROM AUTHOR]