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The rational design of metal–organic framework adsorbents is crucial for target gas separation. Herein, we report two three-dimensional MOFs with different topologies by regulating metal ions with amino-functionalized V-type ligands. Adsorption isotherms and Grand Canonical Monte Carlo simulation reveal that UPC-122 with channel-cavity structure has the potential to separate C2H2/C2H4 at room temperature with a separation ratio of 2.35 (50/50). [ABSTRACT FROM AUTHOR]

MgO carbonization is a green and low-carbon soil improvement technology. The use of MgO carbonization to solidify dredged sediment and transform it into road-building materials has significant environmental sustainability advantages. A series of microscopic characterization tests, including X-ray Diffraction (XRD), Scanning Electron Microscope–Energy Dispersive Spectrometer (SEM-EDS), and Mercury-in-Pressure (MIP) tests, were conducted to elucidate the evolution characteristics of mineral composition, microscopic morphology, and pore structure of sediment under carbonation. Based on the results, the mechanism of MgO carbonation–solidification of dredged sediment was explored. In order to verify the improvement of carbonation on the road performance of sediment, comparative tests were carried out on sediment, non-carbonated sediment, and carbonated sediment. The results indicate a significant improvement in the solidification of MgO-treated sediment through carbonation, with enhanced macroscopic strength and densified microscopic structure. This can be attributed to the encapsulation, cementation, and pore-filling effects of the hydration products and carbonation products of MgO on soil particles. The rebound modulus and splitting strength of carbonated sediment were 3.53 times and 2.16 times that of non-carbonated sediment, respectively. Additionally, the carbonated sediment showed improved saturated stability, resistance to salt solution wet–dry cycles, and resistance to freeze–thaw cycles. [ABSTRACT FROM AUTHOR]

The growing problems of soil erosion and sedimentation due to plantation and construction activities highlight the importance of reliable information on sediment sources with the objectives of designing and implementing targeted management practices. However, reliable information is unavailable for mountainous catchments in southern China. Accordingly, the fingerprinting approach was adopted to quantitatively identify sediment sources in a typical mountainous catchment disturbed by plantation and construction activities in the Dadingshan catchment, Guangdong Province, China. Sensitivity tests were conducted to evaluate the effect of correction factors on the modified model. The results indicated that geochemical elements could be applied for identifying sediment sources within the study catchment. However, the coarse sediment in the catchment posed challenges to the conservative behaviour of tracers. The findings suggested that the primary sediment source is exposed subsoil (51.5 ± 10.0%), followed by plantation topsoil (35.3 ± 16.2%) and wind farms (13.2 ± 10.2%). The mean goodness‐of‐fit value for all sediment samples was 87.1 ± 5.7%. The sediment contributions of various sources varied significantly due to differences in the extent and intensity of human intervention and the main erosion type of each source. Sensitivity analysis revealed that considering the assumption of source normality improved the source apportionment accuracy. However, particle size correction and tracer within‐source variability weighting in the modified mixing model resulted in unusual estimates of the source contributions. This contribution highlights the significance of considering uncertainties in key fingerprinting‐related aspects and emphasizes the need for implementing sediment control strategies in degraded forest environments. [ABSTRACT FROM AUTHOR]

The use of computational modeling algorithms to guide the design of novel enzyme catalysts is a rapidly growing field. Force-field based methods have now been used to engineer both enzyme specificity and activity. However, the proportion of designed mutants with the intended function is often less than ten percent. One potential reason for this is that current force-field based approaches are trained on indirect measures of function rather than direct correlation to experimentally-determined functional effects of mutations. We hypothesize that this is partially due to the lack of data sets for which a large panel of enzyme variants has been produced, purified, and kinetically characterized. Here we report the kcat and KM values of 100 purified mutants of a glycoside hydrolase enzyme. We demonstrate the utility of this data set by using machine learning to train a new algorithm that enables prediction of each kinetic parameter based on readily-modeled structural features. The generated dataset and analyses carried out in this study not only provide insight into how this enzyme functions, they also provide a clear path forward for the improvement of computational enzyme redesign algorithms.

The circadian clock system orchestrates daily behavioral and physiological rhythms, facilitating adaptation to environmental and internal oscillations. Disruptions in circadian rhythms have been linked to increased susceptibility to various diseases and can exacerbate existing conditions. This review delves into the intricate regulation of diurnal gene expression and cell function by circadian clocks across diverse tissues.. Specifically, we explore the rhythmicity of gene expressions, behaviors, and functions in both immune and non‐immune cells, elucidating the regulatory effects and mechanisms imposed by circadian clocks. A detailed discussion is centered on elucidating the complex functions of circadian clocks in regulating key cellular signaling pathways. We further review the circadian regulation in diverse diseases, with a focus on inflammatory diseases, cancers, and systemic diseases. By highlighting the intimate interplay between circadian clocks and diseases, especially through clock‐controlled cell function, this review contributes to the development of novel disease intervention strategies. This enhanced understanding holds significant promise for the design of targeted therapies that can exploit the circadian regulation mechanisms for improved treatment efficacy. [ABSTRACT FROM AUTHOR]

Using a data set from our laboratory, we assessed the effects of several factors on pig cloning efficiency. The results demonstrated that cells at high confluence (>90%) used as donor cell resulted in higher pregnancy rate, delivery rate and overall cloning efficiency (number of live offspring born per reconstructed embryo transferred to recipients) compared with the cells at 60% to 79% confluence and 80% to 89% confluence. Cells with four, five and six passages compromised the pregnancy and delivery rates compared with first passage cells. The number of blastocysts transferred by somatic cell nuclear transfer (SCNT) did not significantly affect the cloning efficiency, but transfer of blastocyst derived from in vitro culture 5 d after SCNT achieved a significantly higher pregnancy rate compared with one to two cell SCNT embryos from overnight culture. The highest pregnancy rate, delivery rate and the largest litter size were obtained when Bama Miniature pig fibroblasts were used as donor cells and Landrace/Yorkshire hybrid gilts were used as recipients. Recipients treated with chemicals for estrus synchronization had higher pregnancy rates compared with untreated recipients. Our data might be helpful for improving SCNT efficiency in pigs.