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South Africa is a country that combines considerable coal mines, coal reserves and natural resources, environmental issues, and water scarcity. Increasing concerns with the carbon footprint and carbon dioxide emissions worldwide have led to a growing number of scholars studying the coal mining field. According to the research, the influences of coal mining in South Africa are dissected. The positive influence is that coal mining improves the South African economy, expressive of impacts on export, domestic consumption, GDP, and employment. However, coal mining damages the environment, evidently in water and air, which harms people’s and animals’ health. Depending on the backgrounds and facts of South Africa, the environmental issues should be given more consideration because they may threaten South Africa in the long term. Fortunately, two environmental policies, including damage land tax (DLT) and environmental bonds, are referred to solve the issue brought about by coal mining. Therefore, the economic effects of coal mining are the benefits for South Africa; the environmental influences are the cost.

Isobavachalcone (IBC) is one of the flavonoid components in Fructus Psoraleae, and has been found multiple pharmacological effects. However, the hepatotoxicity of IBC has been overlooked and not been carefully studied. We aim to find out the cytotoxicity of IBC on HepG2 cells, and explore the underlying mechanisms. HepG2 cells were treated with IBC for 24 h, then MTT assay and LDH assay were used to detect the cell viability. The apoptosis and reactive oxygen species (ROS) production were reflected by the flow cytometry. Using Seahorse Analyzer, we measured the mitochondrial respiratory capacity. The expression of oxidative stress and mitochondrial apoptosis-related proteins were determined by Western blot. The results showed that IBC induced the cell death and apoptosis of HepG2 cells. IBC initiated the accumulation of ROS in cells and impaired the mitochondrial function, triggered apoptosis and suppressed the phosphorylation of Akt. Additionally, scavenging ROS by the antioxidant N-acetyl-l-cysteine (NAC) reduced IBC-induced mitochondria damage and increased Akt phosphorylation. Taken together, IBC caused mitochondrial damage and induced hepatotoxicity by ROS accumulation and Akt suppression. Targeting oxidative stress and depressing mitochondrial damage may provide a theoretical basis for the treatment and prevention of IBC-induced hepatotoxicity in clinic.

Herbivorous insects are exceptionally diverse, accounting for a quarter of all known eukaryotic species, but the genetic basis of adaptations that enabled this dietary transition remains poorly understood. Many studies have suggested that expansions and contractions of chemosensory and detoxification gene families – genes directly mediating interactions with plant chemical defenses – underlie successful plant colonization. However, this hypothesis has been challenging to test because the origins of herbivory in many lineages are ancient (>150 million years ago [mya]), obscuring genomic evolutionary patterns. Here, we characterized chemosensory and detoxification gene family evolution acrossScaptomyza,a genus nested withinDrosophilathat includes a recently derived (Scaptomyzahave among the smallest chemosensory and detoxification gene repertoires across 12 drosophilid species surveyed. Rates of gene turnover averaged across the herbivore clade were significantly higher than background rates in over half of the surveyed gene families. However, gene turnover was more limited along the ancestral herbivore branch, with only gustatory receptors and odorant binding proteins experiencing strong losses. The genes most significantly impacted by gene loss, duplication, or changes in selective constraint were those involved in detecting compounds associated with feeding on plants (bitter or electrophilic phytotoxins) or their ancestral diet (yeast and fruit volatiles). These results provide insight into the molecular and evolutionary mechanisms of plant-feeding adaptations and highlight strong gene candidates that have also been linked to other dietary transitions inDrosophila.

Mendelian susceptibility to mycobacterial disease (MSMD) is a rare monogenetic disease, which is characterized by susceptibility to some weakly virulent mycobacteria. Here, we explored the pathogenic genes and molecular mechanisms of MSMD patients. We recruited three patients diagnosed with MSMD from two families. Two novel mutations (c.1228A > G, p.K410E and c.2071A > G, p.M691V) in STAT1 gene were identified from two families. The translocation of K410E mutant STAT1 protein into nucleus was not affected. The binding ability between gamma-activating sequence (GAS) and K410E mutant STAT1 protein was significantly reduced, which will reduce the interaction between STAT1 protein with the promoters of target genes. The M691V mutant STAT1 protein cannot translocate into the nucleus after IFN-γ stimulation, which will affect the STAT1 protein form gamma-activating factors (GAF) and bind the GAS in the promoter region of downstream target genes. Taken together, our results showed that the mutation of K410E led to impaired binding of STAT1 to target DNA, and the mutation of M691V prevented the transport of STAT1 into the nucleus, which led to MSMD. Together, we identified two novel mutations (c.1228A > G, p.K410E and c.2071A > G, p.M691V) in STAT1 gene in MSMD patients, and deciphered the molecular mechanism of MSMD caused by STAT1 mutations.

The field of biocatalysis is expanding owing to the increasing demand for efficient low-cost green chemical processes. However, a feasible strategy for achieving product separation, enzyme recovery, and high catalytic efficiency in biocatalysis remains elusive. Herein, we present thermoresponsive Pickering high internal phase emulsions (HIPEs) as controllable scaffolds for efficient biocatalysis; these HIPEs demonstrate a transition between emulsification and demulsification depending on temperature. Ultra-high-surface-area Pickering HIPEs were stabilized by Candida antarctica lipase B immobilized on starch particles modified with butyl glycidyl ether and glycidyl trimethyl ammonium chloride, thus simplifying the separation and reuse processes and significantly improving the catalytic efficiency. In addition, the switching temperature can be precisely tuned by adjusting the degree of substitution of the modified starches to meet the temperature demands of various enzymes. We believe that this system provides a green platform for various interfacial biocatalytic processes of industrial interest.

Current manufacturing and development processes for therapeutic monoclonal antibodies demand increasing volumes of analytical testing for both real-time process controls and high-throughput process development. The feasibility of using Raman spectroscopy as an in-line product quality measuring tool has been recently demonstrated and promises to relieve this analytical bottleneck. Here, we resolve manual calibration effort by engineering an automation system capable of collecting Raman spectra on the order of hundreds of calibration points from two to three stock seed solutions using controlled mixing. We used this automated system to calibrate multi-product quality attribute models that accurately measured product concentration and aggregation every 9.3 seconds using an in-line flow-cell. We demonstrate the application of a non-linear calibration model for monitoring product quality in real-time during a biopharmaceutical purification process intended for clinical and commercial manufacturing. These results demonstrate potential feasibility to implement quality monitoring during GMP manufacturing as well as to increase CMC understanding during process development, ultimately leading to more robust and controlled manufacturing processes.

An engineered platelet-based delivery cyto-carrier was developed with a homing ability toward tumors and bleeding injury sites, as well as increased affinity mediated by glucose and GLUT1 to achieve accurate drug delivery to tumors.

Sound field reproduction algorithms require loudspeaker directivity, which is usually measured at discrete frequencies. A time domain model of loudspeaker directivity benefits broadband applications. This Letter proposes the concept of a directional wave front in the time domain, which could be linked to loudspeaker impulse responses measured on a spherical surface. The observed signal in the time domain at the boundary of a spherical region due to a propagating directional wave front is illustrated using a geometric model. Based on the geometric model, the spherical harmonic decomposition of the observed signal in the time domain is also derived.

The integrated energy system (IES) is recognized as a promising energy utilization approach enabled to both improve the energy efficiency and reduce pollutant emissions. Although the economic-environmental dispatch (EED) problem of the IES has been widely studied, the fact that the IES is operated under off-design conditions, having a significant influence on the efficiency of energy devices, is neglected usually, resulting in the scheduled operations, for the IES could not be accurate enough in many actual situations. This study investigates the EED problem of the IES under off-design conditions. Technically, by integrating an efficiency correction process into the traditional energy hub (EH) model, a dynamic energy hub (DEH) model is first formulated for adapting itself to variable energy conversion efficiencies. Then, a deep neural network (DNN)-based efficiency correction method is proposed to predict and correct the time-varying efficiency of energy devices based on three main off-design conditions including the load rate, air temperature, and pressure. A multi-objective EED model is finally formulated for the IES, with the framework of the DEH model, aiming at establishing a trade-off between operational cost and emitted pollutants. Case studies show that the proposed approach helps in enhancing the accuracy of IES dispatch while having a good performance in both the operational cost and pollutant emission reduction.

Coal spontaneous combustion often occurs in storage processes, especially for low-rank coal with high volatile materials, which may lead coal yard caught fire and coal thermal energy losses. Therefore, it is important to accurately predict the spontaneous combustion tendency under coal storage status in real time. In order to determine the ignition point, the existing methods are all using pulverized coal samples, adding special oxidant artificially and then heating to accelerate the oxidation process. The particle size and the test conditions of those methods were quite different from the real coal storage condition. This research developed a new test method to evaluate the spontaneous combustion tendency. The method used granular coal samples, which the particle size is similar to its storage process, to test its temperature increasing under the humidity, pressure and air flow which are similar to its storage conditions. The spontaneous combustion tendency was judged by the temperature rise rate V70 of the sample at 69°C–71°C in adiabatic heating condition. 10 samples of different rank of Chinese coals were used to study. The results show that lignite had the largest low-temperature oxidation heating rate, and anthracite has the minimum. The lower coal moisture, the greater low-temperature oxidation heating rate. When the environment temperature is 70°C, with the increase of air flow rate, the rate of temperature rise increases firstly and then decreases. As environment temperatures rise, the temperature rise rate increases firstly and then decrease for the three types of coal samples, lignite has the maximum temperature rise rate, while anthracite has minimal temperature rising rate. Six kinds of coal samples were selected in order to verify the method precision. It was found that the temperature rise rate and repeatability limit of coal samples have linear correlation, and the basis for judgment and repeatability limit of the method are also provided. The method has high sensitivity and resolution of different coal ranks. According to the research, coal could be divided into three categories: strong spontaneous combustion tendency, medium spontaneous combustion tendency and weak spontaneous combustion tendency according to their temperature rise rate V70. The method could give great practical significant guidance for the scientific storage, blending, safety and efficient utilization of coal.

An organocatalyzed reversible Michael reaction has been implemented for the α-position deuteration of enals with a high level of deuterium incorporation.

Water electrolysis is a promising technique for carbon neutral hydrogen production. A great challenge remains at developing robust and low-cost anode catalysts. Many pre-catalysts are found to undergo surface reconstruction to give high intrinsic activity in the oxygen evolution reaction (OER). The reconstructed oxyhydroxides on the surface are active species and most of them outperform directly synthesized oxyhydroxides. The reason for the high intrinsic activity remains to be explored. Here, a study is reported to showcase the unique reconstruction behaviors of a pre-catalyst, thiospinel CoFe2 S4 , and its reconstruction chemistry for a high OER activity. The reconstruction of CoFe2 S4 gives a mixture with both Fe-S component and active oxyhydroxide (Co(Fe)Ox Hy ) because Co is more inclined to reconstruct as oxyhydroxide, while the Fe is more stable in Fe-S component in a major form of Fe3 S4 . The interface spin channel is demonstrated in the reconstructed CoFe2 S4 , which optimizes the energetics of OER steps on Co(Fe)Ox Hy species and facilitates the spin sensitive electron transfer to reduce the kinetic barrier of O-O coupling. The advantage is also demonstrated in a membrane electrode assembly (MEA) electrolyzer. This work introduces the feasibility of engineering the reconstruction chemistry of the precatalyst for high performance and durable MEA electrolyzers. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version The authors thank the support from the Singapore Ministry of Education Tier 2 Grant (MOE-T2EP10220-0001) and the Singapore National Research Foundation under its Campus for Research Excellence and Technological Enterprise (CREATE) programme, through the Cambridge Center for Carbon Reduction in Chemical Technology (C4T) and eCO2EP programmes.

Tissue engineering technology provides a new treatment to the cartilage damage. Recent progress has focused on coating strategies with the printed scaffold surface, using various materials such as bioactive nanocomposites. However, the fracture and exfoliation of printed scaffolds remain challenges due to their poor adhesion on smooth substrates. These limitations can be offset by developing a versatile film. Here, inspired by the mechanism of the wet adhesion of snails, we introduced a biomimetic nanoscale gelatin film between a smooth conductive slide and a scaffold, which enhanced early cell adhesion rates through water absorption, swelling and adhesion. A bionic technique of preparing gelatin nanofilms and PVP/PCL 3D scaffolds, which involved E-Jet atomization deposition and E-Jet printing techniques based on the electrohydrodynamic effect, was investigated. It is found that the composite scaffold with 400 nm gelatin nanofilm significantly enhances cell attachment (from 62 % to 87 %) and proliferation (increased 6.5 times in 7 days). Collectively, this study highlights the combination of biomimetic nanoscale adhesive film in promoting cell adhesion and cartilage differentiation, which benefiting from water absorption and swelling of gelatin nanofilm. This work provides a new idea for the potential application in the orthopedics field.