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The reliability of hourly PM2.5 data obtained from air quality monitoring stations is compromised as a result of the missing values, thereby impeding the thorough examination of crucial information. In this paper, we present a spatiotemporal (ST) stacking machine learning (ML) method with daily‐cycle restrictions for reconstructing missing hourly PM2.5 records. First, the ST neighbors for the target station with missing values are selected at a daily scale. Subsequently, the non‐null data within the ST neighbors undergo an iterative P‐BSHADE interpolation process for re‐interpolation. Next, a stacking ML model is constructed using the re‐interpolation values and several environmental factors associated with PM2.5 as the predictors, while the observed PM2.5 is taken as the independent variable. Finally, the missing values are reconstructed by inputting the predictors into the trained stacking model. The study utilized hourly PM2.5 data in the Beijing‐Tianjin‐Hebei region as a case study to assess the effectiveness of the proposed method, using daily missing ratios of 10%, 30%, and 50%, respectively. The accuracy of the proposed method was then compared to four contemporary ST interpolation methods. The results indicate that the proposed method exhibits superior performance compared to the classical methods. Specifically, it achieves a reduction in the average root mean square error and mean absolute error by at least 40.6% and 40.1%, respectively. Additionally, the proposed method demonstrates the successful recovery of extreme values in the hourly PM2.5 records, in contrast to the classical methods which often exhibit a tendency to overestimate low values and underestimate high values. Overall, the proposed method presents a viable and efficient approach to recover missing values in the hourly PM2.5 records that demonstrate evident daily periodic patterns. [ABSTRACT FROM AUTHOR]

Determining the minimum supercooling temperature (Tsc) of unsaturated saline soils is the key scientific problem in cold‐region agricultural and engineering, and theoretical models with good predictability are urgently needed. This study establishes a framework for pore solution freezing nucleation in unsaturated saline soils, the chemical potential energy balance equation was established by determining phase transition driving force and potential energy barrier for the formation of stable crystal embryos. Finally, the physical model was constructed. By citing 46 sets of data from different researchers, the validity of the prediction results of this paper's model under different soil types and cooling rates is demonstrated, and the microscopic mechanism of supercooling occurring in the pore solution of positive permafrost is elucidated. The analysis found that electrolyte action restricts the free diffusion of molecules and promotes nucleation to occur, so that a maximum value of Tsc exists during the growth of salinity (in NaCl saline soils occurs at a solution concentration of 0.26 mol/L). Too fast cooling rate will lead to a lag in crystallization time and an increase in supercooling. The combined water content determines the Tsc when rc < 1 μm (pore size), and the effect of changes in water content and cooling rate on supercooling is more significant in small pores; the electrolyte concentration determines the Tsc when rc > 1 μm, Tsc‐max from concentration changes will be more significant in large pores. This study can provide theoretical reserves for controlling the freezing process of soils, studying the mechanism of freezing‐thawing hysteresis, and improving the related numerical calculation models. Plain Language Summary: Permafrost and seasonal permafrost cover more than 50% of land area in the world. The engineering problems caused by freezing‐thawing cycles seriously affect engineering safety and people's well‐being in many countries. Therefore, an in‐depth study of the soil freezing‐thawing cycle is necessary. The water in the soil pore space remains sometimes in liquid state when it is below the freezing temperature. This phenomenon is usually referred to as supercooling. There is still a lack of quantitative studies on the minimum temperature that can be reached by this phenomenon. In this paper, a model that can reasonably predict the minimum subcooling temperature of soil is developed based on thermodynamic methods. The model is verified to be of good accuracy by means of measured data from different researchers. Subsequently, the supercooling characteristics of the soil are discussed based on the model and the microscopic mechanism of the gradual development of freezing in the supercooling state is described. This study will help to recognize and control the soil freezing process in engineering and agricultural construction, and serve to protect engineering structures. Key Points: A physical model is proposed to quantify the supercooling degree of unsaturated saline soilsA maximum value of soil minimum supercooling temperature will occur with increasing salt concentrationToo fast cooling rate will lead to a lag in crystallization time and an increase in supercooling [ABSTRACT FROM AUTHOR]

The clarification of freezing in a soil‐water system is critical for assessing the formation of a freezing zone and liquid water flow. The supercooling phenomenon of soil pore solutions has been found during the freezing process, but the mechanism remains poorly understood. In this study, we propose a free energy function of soil‐water systems based on the Classical Nucleation Theory. The analytical solution of the critical nucleation problem of saline soil‐water system is obtained by combining the initial freezing temperature model and Pitzer activity coefficients model in electrolyte solutions. Then, the freezing‐thawing experiments of saline soil with various salt contents were conducted for verifying the analytical solution. The derived boundary nucleation rate is the quantitative solution of the critical condition for the supercooling. The findings suggested that the theory results agreed well with the experiment results. For the salt‐free soil‐water system, the critical maximum radius of supercooling was 7.15 nm. We compared eight classical ice‐water interfacial tension models, and the "Reinhardt & Doye" and "DeMott & Rogers" models showed excellent performance when using the new free energy theoretical framework to predict the crystallization nucleation rate of soil‐water systems. A positive correlation between the boundary nucleation rate and soil‐water potential is detected. According to the influencing factors, the boundary nucleation rate of soil‐water system can be divided into three zones: salt nature control zone (R > 100 μm), salt‐pore mixed control zone (100 μm > R > 100 nm), and pore size control zone (R < 100 nm). Plain Language Summary: Unfrozen water refers to the soil moisture that still exists in the form of liquid water in the soil at negative temperatures, which is critical for determining the material properties of frozen soil. The phenomenon of soil water not being able to freeze as soon as the temperature falls below the freezing temperature is referred to as "supercooling." However, the critical condition of supercooling is still unclear. In this paper, we developed a nucleation model that can be applied to saline soils based on the thermodynamic approach. Subsequently, the critical conditions were verified by freezing‐thawing tests of soil samples with different salt contents. We further optimized the model of this paper by selecting the best model for the intermediate variables. Quantitative relationships between the initiation condition of supercooling and soil properties were established. We also delineated pore size intervals for distinguishing differences in supercooling properties at different pore sizes. The proposed theoretical framework is developed from Classical Nucleation Theory, which may provide a theoretical reference for revealing the freezing‐thawing mechanism of soil‐water systems. Key Points: There is supercooling in the freezing process and not supercooling‐jump phenomenon in the melting processThe boundary nucleation rate is proportional to the soil water potentialThere exists a critical pore size for the non‐saline soil where supercooling‐jump occurs, and the value is at the 10 nm level (7.15 nm) [ABSTRACT FROM AUTHOR]

ALAS1 is a member of the α‐oxoamine synthase family, which is the first rate‐limiting enzyme for heme synthesis and is important for maintaining intracellular heme levels. In the ovary, ALAS1 is associated with the regulation of ovulation‐related mitochondrial P450 cytochromes, steroid metabolism, and steroid hormone production. However, there are few studies on the relationship between ALAS1 and reproductive traits in goats. In this study, a mutation located in the promoter region of ALAS1 (g.48791372C>A) was found to be significantly (p < 0.05) associated with the kidding number of Yunshang black goats. Specifically, the mean kidding number in the first three litters and the kidding numbers of all three litters were significantly (p < 0.05) higher in individuals with the CA genotype or AA genotype than in those with the CC genotype. To further investigate the regulatory mechanism of ALAS1, the expression of ALAS1 in goat ovarian tissues with different genotypes was verified by real‐time quantitative PCR. The results showed that the expression of ALAS1 was significantly higher in the ovaries of individuals with AA genotype than those with AC and CC genotypes (p < 0.01), and the expression trend of transcription factor ASCL2 was consistent with ALAS1. Additionally, the ALAS1 g.48791372C>A mutation created a new binding site for the transcription factor ASCL2. The luciferase activity assay indicated that the mutation increased the promoter activity of ALAS1. Overexpression of the transcription factor ASCL2 induced increased expression of ALAS1 in goat granulosa cells (p < 0.05). The opposite trend was shown for the inhibition of ASCL2 expression. The results of real‐time quantitative PCR, EdU and Cell Counting Kit‐8 assays indicated that the transcription factor ASCL2 increased the proliferation of goat granulosa cells by mediating the expression of ALAS1. In conclusion, the transcription factor ASCL2 positively regulated the transcriptional activity and expression levels of ALAS1, altering granulosa cell proliferation and the kidding number in goats. [ABSTRACT FROM AUTHOR]

The principal function of inflammation is cellular defence against 'danger signals' such as tissue injury and pathogen infection to maintain the homeostasis of the organism. The initiation and progression of inflammation are not autonomous as there is substantial evidence that inflammation is known to be strongly influenced by 'neuroimmune crosstalk', involving the production and expression of soluble signalling molecules that interact with cell surface receptors. In addition, microbiota have been found to be involved in the development and function of the nervous and immune systems and play an important role in health and disease. Herein, we provide an outline of the mechanisms of neuroimmune communication in the regulation of inflammation and immune response and then provide evidence for the involvement of microbiota in the development and functions of the host nervous and immune systems. It appears that the nervous and immune systems in multicellular organisms have co‐evolved with the microbiota, such that all components are in communication to maximise the ability of the organism to adapt to a wide range of environmental stresses to maintain or restore tissue homeostasis. [ABSTRACT FROM AUTHOR]

All living organisms have developed processes to sense and address environmental changes to maintain a stable internal state (homeostasis). When activated, the p53 tumour suppressor maintains cell and organ integrity and functions in response to homeostasis disruptors (stresses) such as infection, metabolic alterations and cellular damage. Thus, p53 plays a fundamental physiological role in maintaining organismal homeostasis. The TP53 gene encodes a network of proteins (p53 isoforms) with similar and distinct biochemical functions. The p53 network carries out multiple biological activities enabling cooperation between individual cells required for long‐term survival of multicellular organisms (animals) in response to an ever‐changing environment caused by mutation, infection, metabolic alteration or damage. In this review, we suggest that the p53 network has evolved as an adaptive response to pathogen infections and other environmental selection pressures. [ABSTRACT FROM AUTHOR]

Because there is no effective treatment for late‐stage prostate cancer (PCa) at this moment, identifying novel targets for therapy of advanced PCa is urgently needed. A new network‐based systems biology approach, XDeath, is developed to detect crosstalk of signaling pathways associated with PCa progression. This unique integrated network merges gene causal regulation networks and protein‐protein interactions to identify novel co‐targets for PCa treatment. The results show that polo‐like kinase 1 (Plk1) and DNA methyltransferase 3A (DNMT3a)‐related signaling pathways are robustly enhanced during PCa progression and together they regulate autophagy as a common death mode. Mechanistically, it is shown that Plk1 phosphorylation of DNMT3a leads to its degradation in mitosis and that DNMT3a represses Plk1 transcription to inhibit autophagy in interphase, suggesting a negative feedback loop between these two proteins. Finally, a combination of the DNMT inhibitor 5‐Aza‐2'‐deoxycytidine (5‐Aza) with inhibition of Plk1 suppresses PCa synergistically. [ABSTRACT FROM AUTHOR]

Reported is a highly chemoselective intermolecular annulation of indole‐based biaryls with bromoalkyl alkynes by using palladium/norbornene (Pd/NBE) cooperative catalysis. This reaction is realized through a sequence of Catellani‐type C−H alkylation, alkyne insertion, and indole dearomatization, by forming two C(sp2)−C(sp3) and one C(sp2)−C(sp2) bonds in a single chemical operation, thus providing a diverse range of pentacyclic molecules, containing a spiroindolenine fragment, in good yields with excellent functional‐group tolerance. Preliminary mechanistic studies reveal that C−H bond cleavage is likely involved in the rate‐determining step, and the indole dearomatization might take place through an olefin coordination/insertion and β‐hydride elimination Heck‐type pathway. [ABSTRACT FROM AUTHOR]

Abstract: Reported is a highly chemoselective intermolecular annulation of indole‐based biaryls with bromoalkyl alkynes by using palladium/norbornene (Pd/NBE) cooperative catalysis. This reaction is realized through a sequence of Catellani‐type C−H alkylation, alkyne insertion, and indole dearomatization, by forming two C(sp2)−C(sp3) and one C(sp2)−C(sp2) bonds in a single chemical operation, thus providing a diverse range of pentacyclic molecules, containing a spiroindolenine fragment, in good yields with excellent functional‐group tolerance. Preliminary mechanistic studies reveal that C−H bond cleavage is likely involved in the rate‐determining step, and the indole dearomatization might take place through an olefin coordination/insertion and β‐hydride elimination Heck‐type pathway. [ABSTRACT FROM AUTHOR]

B 2021 b , I 8 i , 2101458 DOI: 10.1002/advs.202101458 In the original published article, the name of Jianlin Wang was spelt incorrectly. The updated author byline is shown above. Co-Targeting Plk1 and DNMT3a in Advanced Prostate Cancer. [Extracted from the article]

The chemical shifts of the aromatic hydrogens of 12 symmetrical imidazolium salts were determined in different deuterated solvents. Based on the magnitude of the chemical shift change for the hydrogens of the imidazolium ion in the various solvents, relationships were developed to determine the relative solute/solvent interactions for these compounds. Owing to different degrees of interactions involving the aromatic hydrogens of the imidazolium cations and anions, there is a variation in the interaction of the hydrogens with the solvent molecules. The intimate interaction that exists between the hydrogens of the imidazolium cation and the BF4- anion results in the BF4- salts being less solvated compared with salts containing BF6- and SbF6- anions. For imidazolium salts that contain C2H5, C4H9 and C8H17 side-chains bonded in the 1 and 3 positions, the interaction between H2 and the solvents was observed to be greater than for imidazolium salts with C16H33 substituents. On the other hand, for imidazolium salts that have C16H33 substituents the interaction between H2 and the solvents is similar to that for H4 and H5. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]