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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]

The thermal state of the early Earth's interior and its way of cooling are crucial for its subsequent evolution. Earth is initially hot as it acquired enormous heat in response to violent processes during its formation, e.g., the Moon-forming giant impact, the segregation and formation of its metallic core, the tidal interaction with the early Moon, and the decay of radioactive elements, etc. In the meantime, the cooling mechanisms of early Earth's mantle remain elusive despite their importance, and the previously proposed cooling models of the mantle are controversial. In this paper, we first reviewed several prevalent parameterized thermal evolution models of the early mantle. The models give unrealistic predictions since they were established solely based on a single tectonic regime, such as the stagnant-lid regime, or relied on the disputable existence of the plate tectonics prior to ~ 3.5 Ga. Then we argue that the mantle should have started to cool down from a very hot state after the solidification of the ferocious magma ocean. Instead of using one single scaling law to describe a single-stage model, we suggest that an episodic multi-stage cooling model (EMCM) of the early mantle could be more plausible to account for the mantle's early cooling process. The model reconciles with the fact that the mantle cools down from a hot state prior to ~ 3.5 Ga and can also explain the well-constrained post-3.5 Ga thermal history of the mantle. [ABSTRACT FROM AUTHOR]

Soil total nitrogen (STN) is a crucial component of the ecosystem's nitrogen pool, and accurate prediction of STN content is essential for understanding global nitrogen cycling processes. This study utilized the measured STN content of 126 sample points and 40 extracted remote sensing variables to predict the STN content and map its spatial distribution in the northeastern coastal region of Hebei Province, China, employing the random forest (RF), gradient boosting machine (GBM), and extreme gradient boosting (XGBoost) methods. The purpose was to compare the ability of remote sensing images (Landsat-8, Sentinel-1, and Sentinel-2) with different machine learning methods for predicting STN content. The research results show the following: (1) The three machine learning methods accurately predicted the STN content and the optimal model provided by the XGBoost method, with an R2 of 0.627, RMSE of 0.127 g·kg−1, and MAE of 0.092 g·kg−1. (2) The combination of optical and synthetic aperture radar (SAR) images improved prediction accuracy, with the R2 improving by 45.5%. (3) The importance of optical images is higher than that of SAR images in the RF, GBM, and XGBoost methods, with optical images accounting for 87%, 76%, and 77% importance, respectively. (4) The spatial distribution of STN content predicted by the three methods is similar. Higher STN contents are distributed in the northern part of the study area, while lower STN contents are distributed in coastal areas. The results of this study can be very useful for inventories of soil nitrogen and provide data support and method references for revealing nitrogen cycling. [ABSTRACT FROM AUTHOR]

The inevitable incidents (including accidents and near misses) that occur on construction sites provide opportunities to extract experience, optimize positive outcomes, and decrease the reoccurrence of unwanted events. Learning from incidents (LFI) is defined as an organizational capability to extract experience from incidents and convert them into preventive safety measures. Safety information flow (SIF) and resilient safety culture (RSC) have been found to be closely related to critical aspects of organizational safety management, such as reasoning incident causes and organizational learning. However, the interaction of LFI, SIF, and RSC and how it affects safety performance remain unclear. This study designed a questionnaire to investigate their interrelations. The questionnaire was distributed to construction companies from the Chinese mainland and Hong Kong, and the collected valid responses were analyzed using partial least-squares structural equation modeling (PLS-SEM). The results showed that LFI directly affects the reactive measures of safety performance, i.e., the occurrence frequency of accidents, near misses, and similar events on construction worksites. SIF positively impacts LFI, and RSC plays a mediating role in their relationship. The findings deepen the theoretical interpretation of SIF, RSC, and LFI. SIF facilitates LFI by reasoning the causes of incidents, and RSC provides a supportive environment for upgrading LFI. The findings also guide practitioners to improve LFI and construction safety performance by taking measures to ensure nondefective safety information and smooth information flow within the resilient cultural context. [ABSTRACT FROM AUTHOR]

The consolidation solutions of the foundation penetrated by the concrete-cored gravel (CCG) columns have been proposed based on a single-column model under the axisymmetric condition. A CCG column consists of a precast concrete pile inserted at the center of sand or gravel materials. Numerical modeling is commonly adopted for multicolumn field applications. Converting the axisymmetric unit cell into the plane strain model saves computation load and numerical simulation time. This study proposed a plane strain conversion method for the foundation penetrated by CCG columns. The plane strain conversion goes through a geometric transformation, stiffness equivalence, and consolidation equivalence. The consolidation equivalence is conducted by equating the consolidation degree at any depth of the plane strain model to that of the axisymmetric model. The penetration effect of the converted inner wall is used to modify the equal strain assumption of the plane strain model. The validity of the proposed method is examined by comparing it with 3D numerical simulation results and the field data from an embankment case history. The comparison reveals that the proposed plane strain conversion method enables the numerical simulation of the CCG column-reinforced foundation to be handled easily and largely saves the computation resources. [ABSTRACT FROM AUTHOR]

A concrete‐cored gravel (CCG) column is composed of a precast concrete pile inserted at the center of sand or gravel materials. This technique has been experimentally adopted to support the soft soils in China. However, there has been limited investigation on the consolidation characteristics of a CCG column improved foundation under embankment loading. This study develops analytical solutions for the consolidation of a composite foundation partially penetrated by the CCG columns. The rigid pile's upward and downward piercing effects were considered to improve CCG column‐soil equal strain relationship. The partially penetrated consolidation problem was addressed by assuming the seepages in the unpenetrated layers to be vertical or horizontal and vertical combined. A simplified approximate method was also provided, enabling the users to quickly evaluate the consolidation process of a foundation partially penetrated by the CCG columns. The proposed solution was applied to a case history of an anti‐flood embankment on soft soil with partially‐penetrated CCG columns, and a good agreement was found between predictions and the field measurements. [ABSTRACT FROM AUTHOR]

A surface plasmon resonance imaging (SPRi) platform integrated with a smartphone was constructed for the simultaneous and sensitive detection of acute kidney injury (AKI) biomarkers. The smartphone SPRi platform was developed without the requirement of additional light and power sources. The LED flash of the smartphone was used as the light source for the excitation of surface plasmon resonance of a gold sensor chip based on the Kretschmann configuration, while the reflected light was collected by the camera of the smartphone. This smartphone SPRi system was conveniently fabricated by 3D printing and showed a sensitivity of 1.78 × 10−5 refractive index unit (RIU). In addition, based on a magnetic nanoparticle-enhanced sandwich immunoassay, the smartphone SPRi system with a gold array chip was employed for the detection of multiple AKI biomarkers, with a low limit of detection (LOD) of 0.19 ng ml−1, 0.51 ng ml−1 and 0.7 ng ml−1 for the simultaneous detection of neutrophil gelatinase-associated lipocalin (NGAL), interleukin-18 (IL-18) and retinol-binding protein (RBP) in urine, respectively. The biosensors demonstrated high specificity and sensitivity for the simultaneous detection of multiple AKI biomarkers in PBST and urine. The smartphone SPRi system provided a portable and cost-effective platform for point-of-care diagnosis, in-field healthcare and environmental monitoring. [ABSTRACT FROM AUTHOR]

The Earth's core is composed of iron, nickel, and a small amount of light elements (e.g., Si, S, O, C, N, H and P). The thermal conductivities of these components dominate the adiabatic heat flow in the core, which is highly correlated to geodynamo. Here we review a large number of studies on the electrical and thermal conductivity of iron and iron alloys and discuss their implications on the thermal evolution of the Earth's core. In summary, we suggest that the Wiedemann–Franz law, commonly used to convert the electrical resistivity to thermal conductivity for metals and alloys, should be cautiously applied under extremely high pressure–temperature (P–T) conditions (e.g., Earth's core) because the Lorentz number may be P–T dependent. To date, the discrepancy in the thermal conductivity of iron and iron alloys remains between those from the resistivity measurements and the thermal diffusivity modeling, where the former is systematically larger. Recent studies reconcile the electrical resistivity by first-principles calculation and direct measurements, and this is a good start in resolving this discrepancy. Due to an overall higher thermal conductivity than previously thought, the inner core age is presently constrained at ~1.0 Ga. However, light elements in the core would likely lower the thermal conductivity and prolong the crystallization of the inner core. Meanwhile, whether thermal convection can power the dynamo before the inner core formation depends on the amounts of the proper light elements in the core. More works are needed to establish the thermal evolution model of the core. [ABSTRACT FROM AUTHOR]

The Archean continents, primarily composed of the felsic tonalite–trondhjemite–granodiorite (TTG) suite, were formed or conserved since ~ 3.8 Ga, with significant growth of the continental crust since ~ 2.7 Ga. The difficulty in direct differentiation of the felsic crustal components from Earth's mantle peridotite leads to a requirement for the presence of a large amount of hydrated mafic precursor of TTG in Earth's proto-crust, the origin of which, however, remains elusive. The mafic proto-crust may have formed as early as ~ 4.4 Ga ago as reflected by the Hf and Nd isotopic signals from Earth's oldest geological records. Such a significant time lag between the formation of the mafic proto-crust and the occurrence of felsic continental crust is not reconciled with a single-stage scenario of Earth's early differentiation. Here, inspired by the volcanism-dominated heat-pipe tectonics witnessed on Jupiter's moon Io and the resemblances of the intensive internal heating and active magmatism between the early Earth and the present-day Io, we present a conceptual model of Earth's early crust-mantle differentiation, which involves an Io-like scenario of efficient extraction of a mafic proto-crust from the early mantle, followed by an intrusion-dominating regime that could account for the subsequent formation of the felsic continents as Earth cools. The model thus allows an early formation of the pre-TTG proto-crust and the generation of TTG in the continent by providing the favorable conditions for its subsequent melting. This model is consistent with the observed early fractionation of the Earth and the late but rapid formation and/or accumulation of the felsic components in the Archean continents, thus sheds new light on the early Earth's differentiation and tectonic evolution. [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]

Although previous studies explored the effect of relationships between some factors on hazard identification performance, there is still a need to better understand the interactive mechanisms among factors in the hazard recognition process. This study explored the interactions among factors in the search and decision phases on hazard identification performance. A safety inspection experiment was conducted in a civil engineering laboratory, during which the eye movements of the participants were recorded. The experimental data were entered into a three-way analysis of variance (ANOVA) model to examine the factors' interactions. The results revealed that experience and risk tolerance interactively affect hazard identification performance, and visual clutter and time to first fixation respectively have main effects on hazard identification performance. The findings theoretically supplement knowledge about the interactive mechanisms of factors during the hazard recognition process and will play a critical role in providing practical guidance for safety training. [ABSTRACT FROM AUTHOR]

• We investigate a bipedal inverted pendulum (BIP) model for human–structure interaction. • Model comparison is carried out to show the effect of leg damping on BIP's gaits. • Measured and simulated ground reaction forces are compared in both time and frequency domains. • The ability of the proposed model to cover gait diversity is verified. The bipedal inverted pendulum with damping has been adopted to simulate human–structure interaction recently. However, the lack of analysis and verification has provided motivation for further investigation. Leg damping and energy compensation strategy are required for the bipedal inverted pendulum to regulate gait patterns on vibrating structures. In this paper, the Hunt–Crossley model is adopted to get zeros contact force at touch down, while energy compensation is achieved by adjusting the stiffness and rest length of the legs. The damped bipedal inverted pendulum can achieve stable periodic gait with a lower energy input and flatter attack angle so that more gaits are available, compared to the template, referred to as spring-load inverted pendulum. The measured and simulated vertical ground reaction force-time histories are in good agreement. In addition, the dynamic load factors are also within a reasonable range. Parametric analysis shows that the damped bipedal inverted pendulum can achieve stable gaits of 1.6 to 2.4 Hz with a reasonable first harmonic dynamic load factor, which covers the normal walking step frequency. The proposed model in this paper can be applied to human–structure interaction analysis. [ABSTRACT FROM AUTHOR]

Mycobacterium tuberculosis (Mtb) remains a great threat to global health, killing more people than any other single infectious agent and causing uncontrollable inflammation in the host. Poorly controlled inflammatory processes can be deleterious and result in immune exhaustion. The current tuberculosis (TB) control is facing the challenge of drugs deficiency, especially in the context of increasingly multidrug resistant (MDR) TB. Under this circumstance, alternative host-directed therapy (HDT) emerges timely which can be exploited to improve the efficacy of TB treatment and disease prognosis by targeting the host. Here, we established the in vitro infection model of Mtb macrophages with H37Ra strain to seek effective anti-TB active agent. The present study showed that Guttiferone K, isolated from Garcinia yunnanensis, could significantly inhibit Mtb-induced inflammation in RAW264.7 and primary peritoneal macrophages. It was evidenced by the decreased production of inflammatory mediators, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). Further studies with immunoblotting and immunofluorescence revealed that Guttiferone K obviously inhibits the nuclear factor-kappa B (NF-κB) both in RAW264.7 and primary peritoneal macrophages relying on the TLR/IRAK-1 pathway. Guttiferone K could also suppress the NLRP3 inflammasome activity and induce autophagy by inhibiting the protein kinase B (p-Akt) and mammalian target of rapamycin (mTOR) phosphorylation at Ser473 and Ser2448 in both cell lines. Thus, Guttiferone K possesses significant anti-inflammatory effect, alleviating Mtb-induced inflammation with an underlying mechanism that targeting on the TLR/IRAK-1 pathway and inhibiting the downstream NF-κB and Akt/mTOR signaling pathways. Together, Guttiferone K can be an anti-inflammatory agent candidate for the design of new adjunct HDT drugs fighting against tuberculosis. [ABSTRACT FROM AUTHOR]

Unbalanced snow loads on roofs have been a turbulent and significant problem for the building industry. Gables are one of the most common roof shapes, which are widely adopted as the roof shape for family residences, factories, ware houses, and garages. Series of experiments on an isolated gable-roof with or without scuttles and different roof pitches were done for the purpose of exploring the unbalanced patterns of snow loads. The model buildings made of wood have the same floor space, 2000 × 2000 mm but different roof pitches. A new open air snow–wind combined experimental facility was adopted in the experiments. The facility, which is like an open air wind tunnel with a snowfall simulator, can produce a stable wind field and snowfall environment for a specific duration. Artificial snow was used in the experiments, and particles properties were compared with natural snow previously proposed by the other authors. The experiment results indicated that the unbalanced snow loads were strongly connected with various wind velocities and roof pitches and a scuttle or other salient on the roof would bring an evident influence of patterns of snow distribution on the roofs. [ABSTRACT FROM AUTHOR]

The modified single-walled carbon nanotubes (m-SWCNTs)/poly(ether ether ketone) (PEEK) composites were prepared by solution blending and melt blending, respectively. The mechanical, dielectric, and frictional performances of the m-SWCNTs/PEEK composites obtained by different processing technic were investigated. The poly(aryl ether ketone)s with pyrene (PAEK-Pys) were synthesized through iridium-catalyzed C−H borylation followed by Suzuki coupling. PAEK-Pys were characterized using ultraviolet–visible spectroscopy, proton nuclear magnetic resonance spectroscopy, and gel permeation chromatography. The polymers were then used for surface modification of pristine SWCNTs. Finally, the m-SWCNTs were used to prepare m-SWCNTs/PEEK composites via co-blending in solution or melt. The mechanical, frictional, and dielectric performance of the m-SWCNTs/PEEK composite by solution blending were better than these in m-SWCNTs/PEEK composite by melt blending. These results suggest that the method of solution blending is more favorable for the dispersion of the SWCNTs in PEEK. [ABSTRACT FROM AUTHOR]

The discrepancy between livestock breeding and crop planting in integrated crop-livestock system (ICLSs) usually cause nutrients surpluses to the arable land. Evaluation of regional land bearing capacity and identification of environmental critical regions associated with livestock in China are benefit to nationally- and regionally-specific livestock rearing. This study was conducted to demonstrates the changes in livestock industry from 1996 to 2016 in China and identify the environmentally critical regions of livestock farming by calculating the indexes of bearing capacity of cropland based on nitrogen (I N) and phosphorus (I P). The results revealed that the scale of livestock and poultry farming, manure production, and manure nutrients has increased over the past two decades. The livestock and poultry breeding quantity was 1290.8 million heads with a manure production of 4238.0 million tons in 2016. The manure N and P were 12.0 and 1.9 million tons with an increase of 5.8% and 5.9%, respectively. The N and P demand of crops from manure were 29.1and 4.5 million tons with an increase of 31.5% and 27.2%, respectively. The bearing capacities based on N and P were 2668.9 and 2554.7 million heads in pig equivalent, respectively. On the national level, the I N and I P were 0.43 and 0.45, respectively, which is categorized as Grade II. Livestock rearing in China was still within the bearing capacity of cropland. Both the Northeast and Northwest regions were categorized as Grade I, while Southeast region, Southwest region, the Middle and Lower Reaches of the Yangtze River and the North China were categorized in Grade II. There is still enough space for expansion of livestock and poultry farming in the Northeast and Northwest regions. In the North China region, Southwest region, the Middle and Lower Reaches of the Yangtze River, and the Southeast region, manure generated can be accommodated without any expansion in livestock breeding quantity. While livestock industry in Sichuan, Yunnan, Beijing and Tianjin need to be strictly controlled because of the grade of IV and V. Image 1 • Livestock rearing in China was highly imbalanced among regions due to changes in livestock species abundances. • Nearly 4238.0 million tons of manure contained 12.0 and 1.9 million tons of N and P were generated in 2016. • The livestock bearing capacities based on N and P were 2668.9 and 2554.7 million heads in 2016. • Livestock rearing in China was within the bearing capacity, while some regions faced with potential livestock pollution. [ABSTRACT FROM AUTHOR]

A novel microencapsuled thermal energy storage phase change material (MicroEPCM) based on n‐nonadecane core and CaCO3 shell were synthesized via a self‐assembly method. The chemical structure, surface morphology and thermal properties of the MicroEPCM were investigated by X‐ray diffractometer (XRD), Fourier‐transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetric analyzer (TGA), respectively. The effects of core/shell mass ratios, stirring speed, temperature and emulsifier concentration on the morphology and thermal properties of the MicroEPCM were investigated to confirm the most suitable CaCO3‐encapsulated n‐nonadecane reaction conditions. The results showed that the optimal spherical morphology and the highest latent heat were obtained when the stirring rate is 800 rpm, the temperature is 45 °C, the emulsifier concentration is 15 mmol/L and the core/shell mass ratio is 3:1. The latent heat and encapsulation rate of MicroEPCM as above‐mentioned are 134.83 J/g and 59.68%, respectively. The thermal conductivity of MicroEPCM is improved up to 3.56 times than that of prinstine n‐nonadecane. The MicroEPCM did not leak after being heated at 80 °C for 20 h, which proves that the CaCO3 shell is compact. The MicroEPCM present a good thermal stability after 200 thermal cycling. The MicroEPCM also has been proved to maintain high mechanical strength. [ABSTRACT FROM AUTHOR]

Abstract A general forming method for super-long span mega-latticed structures has been developed, based on the key parameters for five types of structure, together with a finite element model. The method combines the molding idea for universal spherical mega-latticed structures and the geometric topological relations of the improved traditional single-layer reticulated shell. The static and economic indexes of six kinds of 800 m span mega-latticed structures, with the same geometry, control parameters and loads, were calculated, and the force law for these structures under static load identified. Then structures suitable for spans of 1000 m and 1200 m were considered. The static performance and economic indexes showed that the mechanical and economic performance of the Geodesic type mega-latticed structure and the Three-dimensional grid type mega-latticed structure were excellent. In order to promote the engineering application of these structures, the influence of four key parameters on the performance of 1000 m structures was studied, and a reasonable range of indicative parameters obtained. Highlights • It is proved that the modeling method is universal for spherical mega-latticed structures. • The paper can better explain the static properties and the stability of super-long mega-latticed structures. • It is proved that the structure types selected have good mechanical properties and economic performance. • It is proved that through the method of parameter analysis, economic and reasonable structures can be obtained. [ABSTRACT FROM AUTHOR]

Highlights • 7 temperature-based R s models were adopted to improve the Makkink model for ET 0 estimation in Northwest China. • The applicability of the 7 MK i models, original Makkink model, Jensen-Haise and Irmak model were evaluated on different time scales. • The 7 MK i models were more accurate than the 3 physical models. • The M5 model with temperature and relative humidity as input data has the best accuracy. Abstract Reference evapotranspiration (ET 0) is an important parameter for climatological and hydrological studies, as well as for agricultural water resources management. In this study, 7 temperature-based solar radiation models were adopted to improve the Makkink model for ET 0 estimation in Northwest China. The temperature-based models only require air temperature as input data, which can be easily monitored in most areas around the world. The applicability of the improved Makkink models (M1-M7), the original Makkink (MK) model, the Jensen-Haise (JH) model as well as the Irmak (IK) model were evaluated on different time scales using meteorological data obtained from 12 weather stations in Northwest China. The results showed that the 7 improved Makkink (MK i) models (R 2 ranged 0.71–0.86) were more accurate than the 3 physical models (R 2 ranged 0.64–0.76) for daily ET 0 estimation at the 4 sub-zones of Northwest China, and the M4, M5, M6 and M7 models were superior to the other models. The M5 model had the best estimation accuracy for daily ET 0 on daily scale, followed by M7 and M6, with the R 2 median of 0.83, 0.83 and 0.82, the RMSE median of 0.86, 0.88 and 0.89 mm/d, and the GPI median of 1.03, 0.90 and 0.87, respectively. On monthly scale, the 7 MK i models (with relative error almost less than 20%) were also better than the 3 physical models (with relative error usually more than 20%) at the 4 sub-zones. The M5 model also showed the best performance for monthly average daily ET 0 estimation, followed by M7 and M6, with the R 2 median of 1.00, 1.00 and 1.00, the RMSE median of 0.13, 0.16 and 0.19 mm/d, and the GPI median of 0.25, 0.05 and 0.02, respectively. Overall, the estimation accuracy of the Makkink model was much improved by using the temperature-based solar radiation models, and in Northwest China, M5 model which only requires temperature and relative humidity as input data is highly recommended to estimate ET 0 on both daily and monthly scales. [ABSTRACT FROM AUTHOR]

Mn 2 O 3 as a typical Mn based semiconductor has attracted growing attention due to its peculiar 3 d electron structure and stability, and the multi-valence Mn on the surface is the key to peroxydisulfate activation. Herein, an octahedral structure of Mn 2 O 3 with (111) exposed facet was synthesized by a hydrothermal method, which was further sulfureted to obtained a variable-valent Mn oxide for the high activation efficiency of peroxydisulfate under the light emitting diode irradiation. The degradation experiments showed that under the irradiation of 420 nm light, S modified manganese oxide showed an excellent removal for tetracycline within 90 min, which is about 40.4% higher than that of pure Mn 2 O 3. In addition, the degradation rate constant k of S modified sample increased 2.17 times. Surface sulfidation not only increased the active sites and oxygen vacancies on the pristine Mn 2 O 3 surface, but also changed the electronic structure of Mn due to the introduce of surface S2−. This modification accelerated the electronic transmission during the degradation process. Meanwhile, the utilization efficiency of photogenerated electrons was greatly improved under light. Besides, the S modified manganese oxide had an excellent reuse performance after four cycles. The scavenging experiments and EPR analyses showed that •OH and 1O 2 were the main reactive oxygen species. This study therefore provides a new avenue for further developing manganese-based catalysts towards high activation efficiency for peroxydisulfate. [Display omitted] • The S-modified manganese oxide were synthesized by hydrothermal process. • ·OH and 1O 2 were the main ROS in the M-1S-90/PDS/LED light system. • The introduction of S greatly promoted the LED light response and valence cycle of Mn. • A reasonable PDS activation mechanism was put forward. [ABSTRACT FROM AUTHOR]

Complete and accurate global solar radiation (Rs) data at a specific region are crucial for regional climate assessment and crop growth modeling. The objective of this paper was to evaluate the capability of 12 solar radiation models based on meteorological data obtained from 21 meteorological stations in China. The results showed that the estimated and measured daily Rs had statistically significant correlations (P<0.01) for all the 12 models in 7 subzones of China. The Bahel model showed the best performance for daily Rs estimation among the sunshine-based models, with average R2 of 0.910, average RMSE of 2.306 MJ m−2 d−1, average RRMSE of 17.3%, average MAE of 1.724 MJ m−2 d−1, and average NS of 0.895, respectively. The Bristow-Campbell (BC) model showed the best performance among the temperature-based models, with average R2 of 0.710, average RMSE of 3.952 MJ m−2 d−1, average RRMSE of 29.5%, average MAE of 2.958 MJ m−2 d−1, and average NS of 0.696, respectively. On monthly scale, Ögelman model showed the best performance among the sunshine-based models, with average RE of 5.66%. The BC model showed the best performance among the temperature-based models, with average RE of 8.26%. Generally, the sunshine-based models were more accurate than the temperature-based models. Overall, the Bahel model is recommended to estimate daily Rs, Ögelman model is recommended to estimate monthly average daily Rs in China when the sunshine duration is available, and the BC model is recommended to estimate both daily Rs and monthly average daily Rs when only temperature data are available. [ABSTRACT FROM AUTHOR]

In previous studies, snowdrifts around different buildings have been investigated in wind or water tunnels, or in the outdoor environment, to ensure proper accessibility and the safety of structures. The pattern of snowdrifts is strongly connected to the speed and incidence angle of the wind. Two sets of experiments have been undertaken to investigate the influence of wind on snowdrift accumulation around a model and another set of experiments have been undertaken to explore the influence on two separated models. The building model is a wooden cube with dimensions of 0.5 × 0.5 × 0.5 m. The experiments are carried out in an open air snow-wind combined experimental facility, which is situated outdoors, like an open air wind tunnel with a snowfall simulator. The facility can produce a stable wind field and snowfall environment for a specific duration. During the experiments, environmental conditions, like temperature and humidity were measured on a PC-4 automatic weather station. The snow used in the experiments came from the natural snowfall on 01/19/2016-01/22/2016. After each experiment, the snowdrift geometry was measured by surveying approximately 300 points around the model. The results reveal that the patterns of snow distribution show a close relationship with the surrounding wind field of buildings. [ABSTRACT FROM AUTHOR]

The aggregation of amyloid-β peptides is associated with the pathogenesis of Alzheimer’s disease, in which the 30–36 fragments play an important part as a fiber-forming hydrophobic region. The fibrillar structure of Aβ30–36 has been detected by means of X-ray diffraction, but its oligomeric structural determination, biophysical characterization, and pathological mechanism remain elusive. In this study, we have investigated the structures of Aβ30–36 hexamer as well as its G33V and L34T mutants in explicit water environment using replica-exchange molecular dynamics (REMD) simulations. Our results show that the wild-type (WT) Aβ30–36 hexamer has a preference to form β-barrel and bilayer β-sheet conformations, while the G33V or L34T mutation disrupts the β-barrel structures: the G33V mutant is homogenized to adopt β-sheet-rich bilayers, and the structures of L34T mutant on the contrary get more diverse. The hydrophobic interaction plays a critical role in the formation and stability of oligomeric assemblies among all the three systems. In addition, the substitution of G33 by V reduces the β-sheet content in the most populated conformations of Aβ30–36 oligomers through a steric effect. The L34T mutation disturbs the interpeptide hydrogen bonding network, and results in the increased coil content and morphological diversity. Our REMD runs provide structural details of WT and G33V/L34T mutant Aβ30–36 oligomers, and molecular insight into the aggregation mechanism, which will be helpful for designing novel inhibitors or amyloid-based materials. [ABSTRACT FROM AUTHOR]

A comparison was made of the static behavior of a double-layer reticulated shell, a local triple-layered reticulated shell, a ribbed type mega-latticed structure and a Kiewitt type mega-latticed structure with the same geometrical parameters and loads. The results show that the Kiewitt type mega-latticed structure has the best structural performance. Then a complex structural configuration was analyzed in detail, using CAD 3D modeling, and a command-flow was developed to create the new structure automatically by ANSYS Parameter Design Language as an innovative structural-programming method. The static analysis and comprehensive stability analysis were conducted. The reasonable values of parameters for the overall buckling mode were summarized and the ultimate bearing capacity was accurately obtained by considering geometrical nonlinear, material nonlinear and initial curvature of the members. The nonlinear equilibrium paths were traced using the Arc-length method. Results indicate that the 800 m Kiewitt type mega-latticed structure has a very low sensitivity to geometrical nonlinear and a low sensitivity to initial curvature of members, but a high sensitivity to material nonlinear. Therefore, the Kiewitt type mega-latticed structure could be regarded as a reasonable super-large span structure with several advantages, including reasonable stresses, clear force transmission lines, economic steel consumption, high stiffness and good bearing capacity. [ABSTRACT FROM AUTHOR]

Previous studies on hazard recognition focused on single-mode neuropsychological responses using eye tracking or neuroimaging techniques, reflecting a limited understanding of the interaction between ocular and brain activities. This study explores the construction workers' meta-cognitive processes underpinning first target fixations using co-registration of eye movement (EM) and electroencephalography (EEG). The authors conducted a hazard recognition experiment to collect EM and EEG signals under free viewing conditions and examined the relationship between visual attention and cognitive processing. The results show that the workers allocated cognitive resources first to processing targets' visual features and then to discriminating safe or hazardous characteristics. Visual perception and conscious discrimination within first fixations are related to the prior detection of surroundings and affect the subsequent refixations. This study promotes evaluating the hazard recognition process in view of synchronous visual search and brain activity and advances the workers' hazard search patterns. • EM and EEG co-registration technique is applied in construction hazard recognition. • The workers' cognitive processes within first attention periods are decoded. • The effects of hazard features on fixation metrics and FRP components are examined. • Interaction of visual attention and cognitive processing is analyzed. [ABSTRACT FROM AUTHOR]

This paper demonstrates a new nanoemulsion NA-R, is an oil-in-water emulsion. It shows the natural distribution of <100 nm particle size. NA-R is able to provide ultralow surface tension of 33 mN/m and ultralow interfacial tension of 1.35 mN/m. When using it to remove the oil from the cuttings, it is able to reduce the contact angle and capillary force on the cuttings particle surface, subsequently, allowed water to penetrate and wet the particle surface and accessible pores. Once the particles surfaces are water-wet, oil will instantly repel from it and easily segregate through centrifuge force. It was found that the oil removal rate in the cuttings after treatment with nanoemulsion cleaning process was able to reach 95.7%. [ABSTRACT FROM AUTHOR]

Mycobacterium tuberculosis (Mtb) remains a significant menace to global health as it induces granulomatous lung lesions and systemic inflammatory responses during active tuberculosis (TB). Micheliolide (MCL), a sesquiterpene lactone, was recently reported to have a function of relieving LPS-induced inflammatory response, but the regulative role of MCL on the immunopathology of TB still remains unknown. In this experiment, we examined the inhibitory effect of MCL on Mtb-induced inflammatory response in mouse macrophage-like cell line Raw264.7 by downregulating the activation of nuclear factor kappa B (NF-κB) and NLRP3 inflammasome. Evidences showed that MCL decreased the secretion of Mtb-induced inflammatory cytokines (IL-1β and TNF-α) in a dose-dependent manner. Meanwhile, MCL dramatically suppressed Mtb-induced activation of iNOS and COX2 as well as subsequent production of NO. Furthermore, MCL inhibited Mtb-induced phosphorylation of Akt (Ser 473) in Raw264.7. According to our results, MCL plays an important role in modulating Mtb-induced inflammatory response through PI3K/Akt/NF-κB pathway and subsequently downregulating the activation of NLRP3 inflammasome. Therefore, MCL may represent as a potential drug candidate in the adjuvant treatment of TB by regulating host immune response. [ABSTRACT FROM AUTHOR]

The susceptibility of purple soil and intensive tillage render the land prone to erosion under heavy precipitations in a sloping cropland in southwestern China. This study aimed to improve the evaluation of the potential benefits of surface protection tillage and organic matter addition to decreasing nutrient losses. A field plot experiment under natural rainfall conditions was conducted, which employed four management practices: conventional downslope tillage system as control (CK), contour tillage (CT) with organic matter addition (CT + OM), CT with wheat straw mulching (CT + SM), and CT combining straw mulching and organic matter addition (CT + OM + SM). Runoff depth, nutrient loads, and soil erodibility were used to estimate the effects of straw mulching and organic matter addition. Results indicated that the runoff depth under CK was largest during the experimental period, with an average of 16.91 mm, and runoff coefficient average was 32%. Compared with CK, the runoff depth under CT + OM, CT + SM, and CT + OM + SM were reduced by 19%, 34%, and 50%, respectively. A significant difference in soil erodibility indicator among the four treatments was indicated (p < 0.05); CK achieved the highest value, whereas CT + OM + SM obtained the least value. In addition, the contour cultivation (i.e., CT approaches) were more sustainable than the downslope tillage system (i.e., CK). Soil erodibility under CK was 9.83 kg ha −1 mm −1 . Meanwhile, soil erodibility under CT + OM, CT + SM, and CT + OM + SM were 8.49, 6.99, and 6.87 kg ha −1 mm −1 , respectively. These values were 14%, 29%, and 30% lower than that of CK, respectively. CK was more susceptible to accelerated erosion compared with the plots with a surface cover or organic addition. This greater erodibility resulted in higher runoff, sediment yield, and associated nutrient loss for CK. The runoff-associated nitrogen losses were mainly controlled by the runoff rate and soil erodibility (p < 0.05). Variations in NO 3 − –N and NH 4 + –N concentration in runoff water were markedly affected by rainfall events and agricultural practice. A significant logarithmic correlation between NO 3 − –N load and runoff depth was identified. NO 3 − –N was proven to be the main form of inorganic nitrogen loss; therefore, fertilizer application of NO 3 − –N should be reduced in the purple soil region. Soil erodibility significantly influenced the available N losses (p < 0.01), which was best described by a positive logarithmic correlation. Soil nutrient concentration also played an important role in nitrogen loss. However, further research is needed to understand the dynamic interactions between soil erodibility as well as soil and nutrient losses. Results indicated that surface protection by CT + OM + SM is one of the good management practices to reduce soil loss by water erosion in regions with intense agricultural activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydroxylamine significantly enhances persulfate activation by copper tailings. • The leached Fe and Cu is below the limits of surface water standards. • Hydroxylamine and Cu(I) mediate the Fe(III)/Fe(II) cycle. • DFT calculations indicate enhanced adsorption of persulfate by hydroxylamine. Solid waste used as a catalyst to treat wastewater is a feasible solution to achieve "waste treating waste", but its treatment efficiency needs to be further improved. This study used waste copper tailings (CT) as a catalyst and hydroxylamine (HA) as an intensifier to construct a new type of persulfate-based advanced oxidation process (CT/HA/PS) to achieve continuous and efficient degradation of organic pollutants. The introduction of HA significantly increased the degradation efficiency of organic pollutants in wastewater. Besides, the presence of HA increased the TOC removal efficiency from 32.55% to 68.26%, and the cyclic degradation efficiency increased from 43.7% to 87.41%. Density functional theory (DFT) calculation and experiments together confirmed that HA not only enhanced the adsorption efficiency of CT and the utilization of PS, but also accelerated the Fe(III)/Fe(II) and Cu(II)/Cu(I) cycling on the CT surface, thereby generating more SO 4 -. XPS analysis suggested that the sulfides on CT surface also provided active sites for PS activation. More importantly, the concentration of metal elements leached from CT is negligible and will not cause secondary pollution. Therefore, this research not only proposes a new type of advanced oxidation process that efficiently degrading organic pollutants in wastewater, but also a new possible way of resource utilization and stabilization of tailings. [ABSTRACT FROM AUTHOR]

The meteorological conditions determine snow evolutions on and around buildings. Those climatic impacts have been independently considered in the current design codes of buildings, namely the wind pressure and the snow load. But snow load estimates are only based on precipitation assessments without considering the joint effect of wind and snow precipitation which lead to wind dominated deposition and snow transport. Thus, the statistics-based data provided by those building codes seem practically inadequate or at least incomplete. Using the data provided by upper-air and ground meteorological stations in northern China, including snowfall, wind velocity, and temperature, as indicators, we propose a series of statistical relationships covering aspects of snow precipitation and snow drifting. For those meteorological indicators that can affect building snow evolutions, more detailed analyses on their spatial and temporal changes have been achieved. The regionalization of snow precipitation features in northern China has also been proposed based on the clustering analysis on meteorological joint effects. The result shows that the snowfall in most northern regions of China is generally not heavy and in the form of a uniform deposition. The wind dominated depositions around buildings are more likely to appear in the regions around the Bohai Sea. • The simultaneousness of wind and precipitation in the snow load code is considered. • Climate impacts on snow evolutions on roofs are assessed via meteorological methods. • Regionalization of snow deposition features in northern China is acquired. [ABSTRACT FROM AUTHOR]

The genus Glycyrrhiza is a small perennial herb that has been traditionally used to treat many diseases across the world. Licorice (Gancao in Chinese) is the dried root and rhizome of G. glabra , G. uralensis or G. inflata. Licorice plays an important role in traditional Chinese medicine (TCM), and is the most frequently used in Chinese herbal formulas. Isoliquiritigenin (ISL) is a flavonoid extracted from licorice, and has been evaluated for its various biological activities, including anti-inflammatory, anti-tumor and anti-oxidant activities. Excessive and persistent inflammation in the Mycobacterium tuberculosis (Mtb) infection is not conducive to the elimination of Mtb, but contributes to serious pulmonary dysfunction. This study aimed to examine the anti-inflammatory effects of ISL in the Mtb infection. In vitro models of Mtb-infected macrophages were established. Murine macrophage Raw 264.7 cells and primary peritoneal macrophages were used in this study. Cell viability was determined by the cell counting kit-8 (CCK-8) assay. The effects of ISL on the secretion levels of interleukin -1β (IL-1β), tumor necrosis factor -α (TNF-α), and interleukin −6 (IL-6) were detected by the enzyme-linked immunosorbent assay (ELISA). The expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) were measured by the real time quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blot. Western blot was used to assess the effects of ISL on the activation of NLRP3 inflammasome and Notch1/NF-κB and MAPK signaling pathways. Immunofluorescence assays was used to detected the translocation of phosphorylation of p65 subunit of NF-κB. It was revealed that ISL inhibited the secretion of IL-1β and the activation of pore-forming protein (gasdermin D, GSDMD) by suppressing the activation of NLPR3 inflammasome induced by Mtb infection. ISL was also shown to have promising inhibitory effects on inflammatory factors, such as TNF-α, IL-6, iNOS and COX2. Regarding the anti-inflammatory mechanism of ISL, it was found that ISL exerted its anti-inflammatory effects by inhibiting the activation of Notch1/NF-κB and MAPK signaling pathways. ISL reduced Mtb-induced inflammation through the Notch1/NF-κB and MAPK signaling pathways. ISL might be used as a potential adjuvant drug to treat tuberculosis by adjusting host immune responses. [Display omitted] • Isoliquiritigenin is a flavonoid from licorice, which is mainly used to treat respiratory and gastrointestinal symptoms. • Isoliquiritigenin exerted its anti-inflammatory effects by Notch1/NF-κB and MAPK signaling pathways in Mtb infection. • Isoliquiritigenin might be used as a potential adjuvant drug to treat tuberculosis by adjusting host immune responses. [ABSTRACT FROM AUTHOR]

A molecularly imprinted film was incorporated on a surface plasmon resonance sensor for the determination of estradiol. The nanometer-imprinted film was synthesized by a grafting approach. First, the gold sensor chip was modified using an iniferter ofN,N-diethylaminodithiocarbamoylmethylstyrene to create the grafted surface. The molecularly imprinted film was grafted on the sensor by ultraviolet light-initiated copolymerization of methacrylic acid and ethylene glycol dimethacrylate in the presence of estradiol as the template. The template was removed to form a molecularly imprinted film with specific recognition sites for estradiol. This approach avoided self-aggregation in solution, and grafting polymerization was confined to the chip surface. The grafting was implemented with in situ monitoring by surface plasmon resonance that provided excellent control of the film thickness. Substrate surfaces modified with and without an estradiol-imprinted film were characterized by contact-angle measurements and scanning electron microscopy. The estradiol-imprinted film was incorporated on a surface plasmon resonance sensor for the determination of estradiol from 10−10to 10−6 mol/L in phosphate-buffered saline. The lowest determined concentration was 10−10 mol/L. Testosterone was used as an analog; suitable selectivity and specificity were obtained for the determination of estradiol. Furthermore, this sensor possessed high reproducibility for analytical measurements. [ABSTRACT FROM PUBLISHER]

A modified Eulerian method for snowdrifts was proposed by introducing the snow particle capture efficiency. The relationships between the modified method and the previous methods were discussed, the results showed that the previous methods are special cases of the modified method. Based on the modified method, the impacts of the location and the height of the interfering building on the snow distribution on the target building were studied. The location of the interfering building seriously affects the snow distribution on the roof of the target building. Four typical interference modes were found through simulations. Significant interference effects on snow load occur when the interfering building is higher than the target building, and it becomes more powerful with the increase of the height of the interfering building. • A modified erosion and deposition model is proposed, introducing the capture efficiency of the falling snow phase. • The Impacts of the location of the interfering building on the snow distribution on the target building are investigated. • The Impacts of the height of the interfering building on the snow distribution on the target building are investigated. [ABSTRACT FROM AUTHOR]

This study conducted experiments on the wind-induced snow drifting around two adjacent cube models, using artificial snow in an open air snow-wind combined experimental facility constructed at the Harbin Institute of Technology (HIT). In particular, 20 experiments were conducted on two adjacent cubes with three different wind directions, three different wind speeds, and four different spacings. They were compared with contrast experiments with a single cube under the same inflow condition. The cube models were two wooden cubes having dimensions of 0.5 × 0.5 × 0.5 m. The drift process of natural snowfall was simulated by scattering snow particles. After snowfall for 25 min in each experiment, the snowdrifts were measured by surveying approximately 300 points around the cubes. Contour maps of the normalized snow depths were drawn and analyzed. The experiments show that the wind direction and speed have a certain influence on a snowdrift. Based on the wind-snow movement mechanism, the relationship between the snowdrift pattern around two cubes and the snowdrift pattern around a single cube was explored. Under the same condition, the snowdrift pattern around the multiple cubes can be deduced from the snowdrift pattern around the single cube. The snowdrift pattern around the downstream cube depends on its spatial position relative to the upstream cube. Moreover, the snowdrift between two adjacent cubes seems to be dependent on a funneling effect. • The process of wind-induced snow drifting was simulated by scattering artificial snow particles in an open air snow-wind combined experimental facility. • The influence of wind direction and wind speed on the snowdrift pattern around the cubes was studied. • Based on wind-snow movement mechanism, the relationship between snowdrift pattern around two cubes and snowdrift pattern around single cube was explored. Under the same conditions, the snowdrift pattern around the multiple cubes can be deduced from the snowdrift pattern around the single cube. • The effect of funneling has a profound effect on the snowdrift pattern between two adjacent cubes. • The snowdrift pattern around the downstream cube depends on its spatial position relative to the upstream cube. [ABSTRACT FROM AUTHOR]

Injection molding is the most widely used process in manufacturing polymer products. The warpage induced during injection molding process has an important influence on the mechanical performance of injection molded products. Therefore, how to optimize process parameters becomes the key issue in improving the mechanical performance of the product towards the expected service conditions. In this paper, a combined artificial neural network and particle swarm optimization (PSO) algorithm method is proposed to optimize the injection molding process. An integrated finite element analysis of the injection molding process, the warpage-induced residual stresses during assembly, and mechanical performance of serviced product is firstly proposed. A back propagation neural network model is then developed to map the complex nonlinear relationship between process parameters and mechanical performance of the product. The PSO algorithm is interfaced with this predictive model to optimize process parameters and thereby significantly improve the mechanical performance. A case study of vehicle window made of polycarbonate (PC) is presented. Optimum values of process parameters are determined to minimize the maximum von Mises stress within the PC vehicle window under impact loading. [ABSTRACT FROM AUTHOR]

Summary Ephemeral gullies or rills are major sediment sources and the primary channel to convey runoff and sediments from hillslopes. Quantifying the detachment rate is important for understanding the erosion process of ephemeral gullies. This study suggests a method to estimate the detachment rate for use in WEPP model, using sediment distribution data along an eroding rill or ephemeral gully under controlled flume experiments, conducted at four slope gradients (8.74%, 17.62%, 26.78%, and 36.38%) and four flow rates (32, 64, 128 and 256 L min −1 ). The experimental soil materials were packed into the flume of 0.5 m wide, 0.6 m deep and 12 m long, to a thickness of 0.5 m at a bulk density of 1300 kg m −3 . Regulated water flow was introduced to soil surface at the upper end of flumes. The detachment rate was calculated from the spatial distribution data of sediment concentrations measured with sediment-laden water samples simultaneously taken along the gullies at one meter intervals. Results showed that the detachment rate was well fitted with downslope distance along the rill or ephemeral gully by an exponential equation. The regression parameters indicated that detachment rate decreases linearly with sediment load in the gully flow. The feedback relationship between sediment load and detachment rate in rill or ephemeral gullies could be adequately represented by the first-order coupling equation for loess soil under steep slopes and high flow rates. The detachment rates along the rills or ephemeral gullies were found to increase with slope gradient and flow rate and the detachment rate was positively related to unit stream power and the deficit between max sediment load and the local sediment load. [ABSTRACT FROM AUTHOR]

V-RAF murine sarcoma viral oncogene homologue B1 ( BRAF) is the most frequently mutated protein kinase in human cancers. The most common mutant BRAF V600E constitutively activates the RAS/ RAF/ MEK/ ERK signaling pathway. BRAF has been validated as an important therapeutic target in human cancers. Phenylaminopyrimidine and unsymmetrical diaryl urea are two privileged pharmacophores in kinase inhibitor drug discovery. Herein, we describe the design of a novel hybrid pharmacophore, 4-phenylaminopyrimidine urea, using the above two pharmacophores. A new series of compounds were in turn synthesized and evaluated to successfully identify selective inhibitors of BRAF and oncogenic BRAF V600E. Once daily oral dosing of lead compound 3 demonstrated sustained antitumor efficacy in A549 human non-small-cell lung cancer xenograft model. Molecular docking suggested that compound 3 might be a type II kinase inhibitor binding to the DFG-out conformation of BRAF. [ABSTRACT FROM AUTHOR]

To investigate the interference effects of building groups with flat roofs on snow load, a modified Eulerian-Eulerian model was proposed and verified by three typical cases. Based on the verified model, the impact of wind velocity on snow distribution on an isolated building with a flat roof was discussed first, and then a series of CFD simulations were carried out to investigate the snow distribution on building groups with the regular and staggered arrangement. The results showed that the amount of snow on the isolated building decreases significantly with the increase of wind velocity. The critical building density of the building group with the regular and staggered arrangement is about 0.25, above which the interference effects of the building groups on snow load are not significant. The interference effects of the building groups with the staggered arrangement on snow load are weaker than that of the building group with the regular arrangement. • A modified Eulerian model of snowdrift is proposed and verified. • The snow distribution on the isolated building is sensitive to wind velocity. • The interference effects on snow load are significant when building density is high. • The interference effects on snow load are seriously affected by building arrangement. [ABSTRACT FROM AUTHOR]

Abstract: Rapid detection of hormones at sub-ng/ml concentrations is of tremendous importance for diagnostic purposes, quality control, and environmental monitoring. In this respect, we report a novel label-free biosensor based on hydrogel optical waveguide spectroscopy (HOWS) for the sensitive detection of 17β-estradiol (E2). This approach was implemented by using a thin hydrogel layer of a carboxylated poly(N-isoproprylacrylamide) (PNIPAAm) terpolymer that was attached to a metallic sensor surface in order to simultaneously serve as a binding matrix and an optical waveguide. Refractive index changes that are accompanied with the specific capture of biomolecules from an aqueous sample on the sensor surface were probed by resonantly excited hydrogel optical waveguide modes. To optically excite and interrogate these waves, an optical setup based on Kretschmann configuration of attenuated total reflection (ATR) method that is compatible with surface plasmon resonance (SPR) was used. We demonstrate that HOWS offers a higher binding capacity, good anti-fouling properties, improved figure of merit, and E2 detection limit of 50pg/ml which is seven times better than that obtained by a regular surface plasmon resonance (SPR) biosensor. [Copyright &y& Elsevier]

Abstract: Chemical N input is essential for high rice yields. However, low recovery efficiency of chemical fertilizer N with flooding irrigation in the anthropogenic-alluvial soil resulted in N lost from the rice field in Ningxia Irrigation Region in the upper reaches of the Yellow River. With the technique of stable isotope 15N-traced urea, we conducted two years experiment to estimate the recovery efficiency and loss of applied chemical fertilizer in a rice field. The three fertilizer N treatments included 300kgha−1 (N300, the conventional application rate), 240kgha−1 (the optimized N application amount, N240) and no N fertilizer application treatment (CK). We estimated the recovery of 15N-labelled urea in grain, straw and root of rice and residues in soil profile. The 15N not accounted for in the plant and soil was presumably lost. The results showed that more efficient use of N fertilizer could allow current N application rates to reduce by 20%. This would still maintain crop yields while substantially reducing N losses to the environment. The high N fertilizer application increased the N uptake by rice derived from fertilizer, and the amount of N rice taken up from soil reduced correspondingly, which resulted in the higher N surplus in soil. Under the conventional irrigation and fertilizer management level, the recovery rate of 15N-labelled urea in rice–soil system was about 48–49%. The 15N-labelled fertilizer recovery in rice plant (N dff ) was 26–30%. In the paddy soil profiles of 0–90cm, the residual of 15N-labelled fertilizer in soil (N dfs) were 54–70kgha−1, and N residual rate in soils were 18–23%. The annual N loss from the rice field in the Irrigation Region was 28,865tons. The distribution of 15N abundance variability in different soil profile indicated that fertilizer N leached into the deep soil layers along with irrigation water as a result of continuous yearly rice planting. Optimization of nitrogen fertilizer can significantly reduce the amount of N residuals and N loss from the paddy field. Compared with N300, optimized nitrogen fertilizer application could decrease the loss of fertilizer N by 22–34kgha−1, and reduce the amount of N surplus by 26–33kgha−1 while the dry matter of rice increased 8–15% and N uptake by rice increased 2–6%. Considering the high food production and the minimum environmental threat, we should fully take into account the optimization application by reducing fertilizer N inputs. However, the interaction between irrigation management and N application rate on N use efficiency in alkaline anthropogenic-alluvial soil needs to be further studied. [Copyright &y& Elsevier]

Abstract: Rill erosion can be a serious problem on cultivated slopes. Understanding the mechanisms of the detachment process in eroding rills is important in developing and improving process-based erosion prediction models. The detachment rate, defined as the sediment amount detached from a unit area in a unit time, is a crucial parameter in most physical erosion prediction models. Most current studies on rill detachment rates use spatially averaged soil erosion data, which provides little information about soil erosion dynamics due to the lack of spatially distributed, contemporaneous rill erosion data. The objective of this study was to estimate the net detachment rate in eroding rills using a rare earth element (REE) tracing method. Flume experiments were conducted with ten REE oxides (Ho2O3, Tb4O7, Eu2O3, Yb2O3, Dy2O3, Sm2O3, La2O3, Tm2O3, CeO2, and Nd2O3) as tracers mixed with soil in different sections of five slopes (8.74%, 17.62%, 26.78%, 36.38%, and 46.6%) exposed to three water flow rates (2, 4, and 8 L min− 1). Regulated water flow was introduced to the upper end of flumes, 8 m long and 0.1 m wide, which were divided into 10 equal segments, each containing a different REE–soil mixture. The net detachment rate from each rill segment was calculated from the REE concentrations in the eroded and transported material. The detachment rates from different segments along the rills, at different slope gradients and flow rates, were compared with those estimated directly from previous studies, and were found to increase with increasing slope gradient and flow rate. Results also showed that the net rill detachment rates decreased linearly with an increase in sediment concentration, and decreased exponentially with an increase in rill length. The REE-derived detachment data and their relationship with sediment concentrations are consistent with the detachment function used in the WEPP model, and are helpful in understanding the processes of rill erosion. Using REEs to trace detachment rates in continuous rills is a valid and advantageous technique for estimating the spatial distribution of the rill detachment rates. [Copyright &y& Elsevier]

We explore the process of modeling aeolian snow transport around buildings by proposing a set of similarity requirements on simulating a single snow fall event with drifting. The similarity criteria are used to guide our wind tunnel tests from the particle selection to the simulation set-up, including the determination of test wind speed, snowfall intensity and transported snow profile. In parallel, a specific field experiment on snow precipitation and drift around a 1-m prototype cube was achieved in Harbin to serve as the reference for the subsequent test validation. After reproducing a target wind and snow environment with a scale of 1:4 versus that of the prototype measurement, two verification tests were put forward using snow and substitution particles, which can mimic the effects of changing wind directions on the snow distribution. Herein, the wind tunnel and outside prototype results show good qualitative agreement in our limited range of length scales and particle properties. In future work, the range of scales and range of parameter values should be increased. [ABSTRACT FROM AUTHOR]

Interactions between the cotton bollworm,Helicoverpa armigera(Hübner) (Lepidoptera: Noctuidae), its larval parasitoidMicroplitis mediator(Haliday) (Hymenoptera: Braconidae), and the Cry1Ac toxin ofBacillus thuringiensisBerliner were evaluated under laboratory conditions. The growth ofH. armigeralarvae was delayed and its pupal rate and pupal weight decreased when they were fed on a diet containing Cry1Ac toxin. Due to the lowered growth rate of the host larvae, the time available for parasitization ofH. armigerabyM. mediatorincreased when the host larvae were reared on a diet containing Cry1Ac toxin at concentrations of 0.5, 1, 2, and 4 µg g−1. The longevity of female and male parasitoids was not significantly affected when newly emerging wasps fed on honey solutions containing three different concentrations of Cry1Ac toxin (125, 250, and 500 µg ml−1). When female parasitoids were fed on honey solutions containing Cry1Ac, their offsprings’ egg and larval development period, pupal weight, length of pupation, adult weight, and adult longevity did not change significantly in most of the treatments compared with controls. When the female parasitoids parasitized host larvae that had been fed on a diet containing 0.5, 1, 2, 4, and 8 µg g−1 Cry1Ac toxin, their offsprings’ eggs and larvae were significantly delayed. Their pupal weight, adult weight, and adult longevity were also significantly less than controls. [ABSTRACT FROM AUTHOR]

The application of the two-dimensional frequency domain least squares (2D-FD-LS) algorithm to parametric-based airborne radar detection is discussed herein. Several issues such as model order selection and model stabilization are considered. The frequency-domain version of the test statistic is also derived here. Simulation-based results demonstrate that good performance can be obtained. [ABSTRACT FROM AUTHOR]

Unbalanced snow distribution is one of the main reasons for the collapse of multi-span arch roofs due to excessive snow loads in the valley and leeward areas. The formation of uneven snowdrifts is closely related to the shape of the building as it seriously affects the turbulent structure and snow drifting process. This study aims to investigate the snowdrift characteristics of multi-span arch roofs based on a multiphase snowdrift approach. Firstly, the prediction accuracy of the flow field is tested to select a reasonable turbulence model. Then, the reliability of this multiphase approach is validated by comparing the results with a wind tunnel experiment of snowdrifts on a multi-span arch roof. The result preliminarily proves that this approach could well reproduce the unbalanced snowdrift on each span roof and at the trough. The snowdrift characteristics of multi-span arch roofs are investigated under different rise/span ratio and span number conditions based on the validated approach. The formation mechanism and characteristics of snowdrifts on different roofs are clarified by analysis. Finally, several typical distribution patterns are derived based on the statistical analysis of results. It is found that the middle-span roof bears a larger snow load than the roofs at both ends. • The paper proposes a multiphase approach that could accurately predict the snowdrifts on arch roofs. • The multiphase approach could well reproduce the snow drifting process and the sliding effect at roof edge. • Two kinds of unbalanced triangular snow loads are formed on the single-span arch roof according to the rise/span ratio. • The stacking snow load at the trough of the multi-span roof is about twice the peak snow load of the single-span roof. • The middle-span arch roof bears a larger snow load than the roofs at both ends of the multi-span building. [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]