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In the powder bed fusion process, an accurate prediction of the transient temperature field of a part is essential to calculate the subsequent thermal stress evolution and microstructure propagation in that part. The experimental method is time-consuming and expensive since the temperature field is controlled by many process parameters. Numerical heat transfer models can be used to estimate the temperature field at any time point. However, traditional numerical simulation schemes are not suitable for the layer-wised fabrication process due to the extremely high computational cost. The computational cost mainly relies on the element number and time step size. This research provides a new efficient and part-level simulation scheme based on an open-source finite element library, which is able to adaptively refine and coarsen the mesh and solve finite element equations with multiple processors in a parallel way. Here, a new mesh strategy that aims to reduce the element number while keeping the solution accuracy is developed. The simulation speed is 12× to 18× faster compared with the traditional simulation scheme depending on the scale of the simulated domain and number of processors. Simulation results have been compared with the experimental results of an Inconel 718 component. It is shown that the testing point in the simulation experiences the same thermal cycles of the same point in the experiment. This simulation scheme can also be used to optimize the process parameters such as scanning pattern, scan velocity, and layer thickness and can be easily extended to other additive manufacturing processes. [ABSTRACT FROM AUTHOR]

Numerical transient thermal analysis of a part during the selective laser melting process is a great challenge due to huge computational cost. An efficient simulation scheme is proposed to estimate the temperature distribution and history in part level. The building domain is coarsely meshed at the beginning. Then, deposited elements are activated layer by layer with desired material properties. The Gaussian distributed heat flux is applied to the top surface and travels according to the predefined scanning path. With the motion of input heat flux, the mesh is continuously refined and coarsened as the laser beam moves in and out. To improve the solution accuracy, temperature-dependent thermal properties in powder and solid state are incorporated in the finite element system. To reduce the computation cost, the Gaussian line heat source with a large time step length is used to replace the traditional moving Gaussian point heat source. To achieve a compromise between the computational efficiency and the solution accuracy, the hybrid of the Gaussian line heat source and Gaussian point heat source is adopted as heat input and results are compared with that of the Gaussian point heat source. The proposed simulation scheme is validated by comparing the simulated geometry of the melt pool with experimental results. Simulation results show that the proposed simulation scheme has the ability to efficiently and accurately predict the temperature field of a part during the selective laser melting process and can be easily extended to other powder bed fusion processes. [ABSTRACT FROM AUTHOR]

Comprehensive assessments and mitigation potential of nitrous oxide (N 2 O) emissions are particularly important, especially in China. We report that the total N 2 O emissions in China increased by 140% from 1978 to 2015, with croplands being the major emitters accounting for 35–48% of the emissions. Over the last 15 years, N 2 O emissions from industry, aquaculture and waste management have grown rapidly, while those from cropland, livestock, grassland, and human consumption have grown slowly. The spatial differences in China make the assessments of N 2 O emission patterns complex. Compared with other greenhouse gas emissions (including carbon dioxide, methane, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride) reported by the World Bank, we found that N 2 O emissions contributed approximately 9–20% (carbon dioxide equivalent) of the major greenhouse gas emissions from 1978 to 2012 in China. The growth rate of N 2 O emissions in China was 1.8 times greater than that throughout the world between 1978 and 2012. Additionally, we assessed the mitigation potential for various measures from the perspectives of production and consumption. The results show that knowledge-based nitrogen management (including the application of controlled-release nitrogen fertilizer, nitrification inhibitor and urease inhibitor, and optimal nitrogen fertilizer rate based on soil nitrogen tests), large farm sizes, flue gas denitration and healthy diet habits are effective strategies to cope with the continued growth of N 2 O emissions. The results of these quantitative scenario simulations are critical for the formulation and implementation of corresponding policy measures. • Temporal and spatial variations in N 2 O emissions were quantified. • The total N 2 O emissions in China increased by 140% from 1978 to 2015. • The N 2 O emissions in China contribute 9–20% of the CO 2 -equivalent GHG emissions. • A quantitative N 2 O mitigation potential is proposed. • Knowledge-based N management is an effective scenario for mitigating N 2 O emissions. [ABSTRACT FROM AUTHOR]

Abstract: China's chemical industry has greatly altered the processes that contribute to reactive nitrogen (Nr) creation and Nr emission. However, the fluxes, fates and environmental consequences of Nr produced by the chemical industry remain poorly understood and unquantified. We report here that Nr creation and Nr emission by the chemical industry increased 47- and 37-fold from 1963 to 2015, respectively. Nr fixation in the chemical industry mainly results from the production of N fertilizer, but Nr fixation by fossil fuel combustion and chemical N products (except N fertilizer) has rapidly increased over the past 15 years. Meanwhile, the manufacture of raw chemical materials and chemical products are the main contributors to waste Nr production. Driving force analysis of Nr creation and Nr emission shows that population growth has the largest positive effect, while urbanization also has varying degrees of impact. Additionally, we propose some policy suggestions to reduce the environmental impact of Nr emissions from the chemical industry based on a brief future perspective of Nr creation and Nr emission. These findings will provide policy makers with an integrated view of Nr metabolism and environmental damage to address the significant challenges associated with reducing emissions in the chemical industry. [ABSTRACT FROM AUTHOR]

[Display omitted] Aberrant alterations of rearranged during transfection (RET) have been identified as actionable drivers of multiple cancers, including thyroid carcinoma and lung cancer. Currently, several approved multikinase inhibitors such as vandetanib and cabozantinib demonstrate clinical activity in patients with RET-rearranged or RET-mutant cancers. However, the observed response rates are only modest and the 'off-target' toxicities resulted from the inhibition of other kinases is also a concern. Herein, we designed and synthesized a series of RET inhibitors based on the structure of selective RET inhibitor BLU-667 and investigated their biological activities. We identified compound 9 as a novel potent and selective RET inhibitor with improved drug-like properties. Compound 9 exhibits a selective inhibitory profile with an inhibitory concentration 50 (IC 50) of 1.29 nM for RET and 1.97 (RET V804M) or 0.99 (RET M918T) for mutant RETs. The proliferation of Ba/F3 cells transformed with NSCLC related KIF5B-RET fusion was effectively suppressed by compound 9 (IC 50 = 19 nM). Additionally, compound 9 displayed less 'off-target' effects than BLU-667. In mouse xenograft models, compound 9 repressed tumor growth driven by KIF5B-RET-Ba/F3 cells in a dose-dependent manner. Based on its exceptional kinase selectivity, good potency and high exposure in tumor tissues, compound 9 represents a promising lead for the discovery of RET directed therapeutic agents and the study of RET-driven tumor biology. [ABSTRACT FROM AUTHOR]

Excessive anthropogenic activities have led to high-level ammonia loss and volatilization, which is regarded as a key factor in Chinese haze formation. In this study, a comprehensive analysis of ammonia emission estimations is accomplished at both temporal (1980–2016) and spatial (provincial) scales using a mass-balanced model, and emission projections through 2030 are also studied in different development scenarios. The results show that the ammonia emissions increased from 4.7 Tg N yr−1 in 1980 to 11 Tg N yr−1 in 2016, which is an approximately 2.4-fold increase. The cropland and livestock emissions are the largest contributors, as most reports show approximately 80% contributions; however, nonagriculture sources of fuel combustion, waste treatment and ammonia escape have grown rapidly in recent years, accounting for 14% in 2016. The spatial differences also reveal the complex heterogeneity in Chinese provinces. In addition, the emission intensities of major agriculture and non-agriculture sources are 0–80 kg N ha−1 yr−1 and over 100 kg N ha−1 yr−1, respectively, indicating a higher degree of ammonia concentration from non-agriculture emissions, which should attract wide concern. In terms of scenario analysis, emissions would reach 12.8 Tg N yr−1 in 2030 under the currently developed model and 7.3 Tg N yr−1 under a series of reduction policies; the spatial analysis also shows that the North China Plain has a 2.1 Tg N yr−1 reduction potential. The results of this study provide new insights into ammonia emission estimations and a better understanding of the environmental impacts of ammonia emitted from different sources. Excessive anthropogenic activities have led to high-level ammonia loss and volatilization, which is regarded as a key factor in Chinese haze formation. In this study, a comprehensive analysis of ammonia emission estimations is accomplished at both temporal (1980–2016) and spatial (provincial) scales using a mass-balanced model, revealing the temporal-spatial differences of the complex heterogeneity in China. In addition, the high-resolution sectorial emission pattern is also revealed by land-use model, indicating a higher degree of ammonia concentration from non-agriculture emissions, which should attract wider concern. Scenario analyses are also studied to reveal the emission tendency in different development scenario. The results of this study provide new insights into ammonia emission estimations and a better understanding of the environmental impacts of ammonia emitted from different sources. Unlabelled Image • Temporal and spatial variations in the ammonia emission were quantified. • The nonagriculture emissions show higher emission intensity with agriculture. • The ammonia emission to 2030 show different trends in scenario analysis. [ABSTRACT FROM AUTHOR]

The continuously increasing amount of solid waste (SW) that is being generated in China calls for environmental assessment and management strategies. However, the pattern and magnitude of the reactive nitrogen (Nr) loss associated with SW have received negligible attention. Here, we established a systematic Nr flow assessment of the generation, treatment and emissions of SW in China from 1978 to 2015. The Nr flow of SW increased by 87% during this period, with the livestock sector being the largest contributor. Composting and animal feed were the two main methods of SW treatment, accounting for more than half, whereas the two fastest growing treatments were remanufacturing and sewage treatment, which increased 13- and 62-fold, respectively. Each SW treatment method would inevitably lead to Nr emissions. Our results showed that the total Nr emissions from SW treatment increased from 8.7 Tg N yr−1 in 1978 to 18.6 Tg N yr−1 in 2015. The development of sustainable SW management requires considering both economic and environmental impacts. We use an optimization model (Solid Waste Optimization Life-Cycle Framework) and provide evidence that recycling SW resources will be an option for economic and environmental trade-offs. Image 1 • Temporal evolution in Nr flow assessment of solid waste was quantified. • Total Nr emissions from solid waste treatment increased by 114% from 1978 to 2015. • The Solid Waste Optimization Life-Cycle Framework is applied for scenario analysis. • Solid waste recycling is an option for economic and environmental trade-offs. [ABSTRACT FROM AUTHOR]

Simple Summary: Accurate farming is essential for optimal pasture management and productivity improvement. Recently, automatic sheep face detection has become a promising solution for accurate farming. In this study, we explore a novel sheep face detection scheme based on lightweight convolutional neural network. The results have shown that our proposed detection method has the characteristics of real-time and robust detection, which provides a potential solution for accurate sheep face detection on actual sheep farms. The accurate breeding of individual sheep has shown outstanding effectiveness in food quality tracing, prevention of fake insurance claims, etc., for which sheep identification is the key to guaranteeing its high performance. As a promising solution, sheep identification based on sheep face detection has shown potential effectiveness in recent studies. Unfortunately, the performance of sheep face detection has still been a challenge due to diverse background illumination, sheep face angles and scales, etc. In this paper, an effective and lightweight sheep face detection method based on an improved RetinaFace algorithm is proposed. In order to achieve an accurate and real-time detection of sheep faces on actual sheep farms, the original RetinaFace algorithm is improved in two main aspects. Firstly, to accelerate the speed of multi-scale sheep face feature extraction, an improved MobileNetV3-large with a switchable atrous convolution is optimally used as the backbone network of the proposed algorithm. Secondly, the channel and spatial attention modules are added into the original detector module to highlight important facial features of the sheep. This helps obtain more discriminative sheep face features to mitigate against the challenges of diverse face angles and scale in sheep. The experimental results on our collected real-world scenarios have shown that the proposed method outperforms others with an F1score of 95.25%, an average precision of 96.00%, a model size of 13.20 M, an average processing time of 26.83 ms, and a parameter of 3.20 M. [ABSTRACT FROM AUTHOR]

[Display omitted] A gram-scale stereoselective synthesis of next generation of Trk Inhibitor LOXO-195 is reported. Starting from two commercially available and cheap building blocks, LOXO-195 is prepared via 9 steps in 26% overall yield with excellent enantioselectivity (ee > 99%). The new synthesis reported herein features a development of an efficient Csp2-Csp3 suzuki coupling from key intermediates 19 and 16 , which allows to make LOXO-195 in a more convergent fashion compared to the reported synthetic route. [ABSTRACT FROM AUTHOR]

Ophiolite provides key information on subduction–accretion processes along convergent plate margins. The Wunuer ophiolite in the Great Xing'an Range of NE China was considered to be an accreted fragment of the Palaeo‐Oceanic Plate. Based on field investigation, we evaluate the petrotectonic assemblages, geochemical features, and formation age of the ophiolite, which comprises gabbro, diabase, metabasalt, and radiolarian bedded chert with serpentinized amphibole‐pyroxene peridotites. Zircon U–Pb dating shows ages of 346 ± 6 Ma and 341 ± 6 Ma suggesting the timing of formation of the ophiolite as Early Carboniferous. The ophiolitic mafic rocks in Wunuer can be divided into two types based on their geochemical features. Type I is characterized by high Ti and low Al, with weakly negative Nb‐Ta and positive Pb anomalies and low light rare earth elements (LREE). These rocks display MORB‐like features, and correspond to partial melting product of depleted mantle. Type II has low Ti, high Al, notably negative Nb‐Ta and positive Pb anomalies, and is obviously enriched in LREE, large‐ion lithophile elements (LILE), and depleted in high‐field‐strength elements (HFSE), characterized by IAB‐like features, and may be formed by partial melting of more depleted mantle, which was strongly metasomatized by subduction fluids, resulted in high LILE/HFSE. The two types of ophiolites belong to SSZ type, obviously influenced by subduction, and their tectonic setting is inferred to be within a spreading ridge in a back‐arc basin. Combined with regional geological background, the Wunuer ophiolite probably represents a shrinking ocean basin and may be the late product of the long‐term and mature back‐arc basin, related to the terminal stage of ridge spreading within the back‐arc basin. [ABSTRACT FROM AUTHOR]

Agriculture has played an indispensable role in the economic and social development of China. However, the inappropriate application of fertilizers in agriculture has brought about environmental pollution. Therefore, under the requirements of green development, the inevitable choice has been reducing the application amount while increasing the utilization rate of fertilizers. To solve the problems resulting from fertilizers, this research designed and made Balanced Nutrient Fertilizer based on the nutrient balance method. To test Balanced Nutrient Fertilizer, continuous planting experiments on three crops (peas, corns, and peaches) were carried out in Pinggu District, Beijing. Furthermore, a substance flow analysis (SFA) was conducted to obtain a deeper understanding of the Balanced Nutrient Fertilizer. Through a series of tests, the application of Balanced Nutrient Fertilizer was shown to increase the crop yield by 3%. The product quality was also improved. In addition, the amount of nutrients applied was significantly reduced in the experimental group (specifically, 35%–88% for nitrogen, 69%–93% for phosphorus, and 8%–82% for potassium). The results of the SFA revealed that applying the Balanced Nutrient Fertilizer could meet the required amount of nutrients for the best crop growth, greatly decrease the negative influence of chemical fertilizers on the soil and reduce agricultural non-point source pollution. Unlabelled Image • Balanced Nutrient Fertilizer can increase yield 3–7% with less fertilizer input. • The total application of NPK has been decreased by 35%–93%. • SFA was used to evaluate the influence of the fertilizer on environment. • A new calculation method of nutrient elements utilization rate [ABSTRACT FROM AUTHOR]