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This study delves into the multifaceted challenges confronting children from vulnerable or fragile families, with a specific focus on learning disabilities, resilience (measured by grit), and material hardship--a factor intricately linked with children's disabilities. Leveraging the predictive capabilities of machine learning (ML), our research aims to discern the determinants of these outcomes, thereby facilitating evidence-based policy formulation and targeted interventions for at-risk populations. The dataset underwent meticulous preprocessing, including the elimination of records with extensive missing values, the removal of features with minimal variance, and the imputation of medians for categorical data and means for numerical data. Advanced feature selection techniques, incorporating mutual information, the least absolute shrinkage and selection operator (LASSO), and treebased methods, were employed to refine the dataset and mitigate overfitting. Additionally, we addressed the challenge of class imbalance through the implementation of the Synthetic Minority Over-sampling Technique (SMOTE) to enhance model generalization. Various ML models, encompassing Random Forest, Neural Networks [multilayer perceptron (MLP)], Gradient-Boosted Trees (XGBoost), and a Stacking Ensemble Model, were evaluated on the Future of Families and Child Wellbeing Study (FFCWS) dataset, with fine-tuning facilitated by Bayesian optimization techniques. The experimental findings highlighted the superior predictive performance of Random Forest and XGBoost models in classifying material hardship, while the Stacking Ensemble Model emerged as the most effective predictor of grade point average (GPA) and grit. Our research underscores the critical importance of tailored policy interventions grounded in empirical evidence to address childhood disabilities within fragile families, thus offering invaluable insights for policymakers and practitioners alike. [ABSTRACT FROM AUTHOR]

Asymmetric cell division generates two daughter cells with distinct characteristics and fates. Positioning different regulatory and signaling proteins at the opposing ends of the predivisional cell produces molecularly distinct daughter cells. Here, we report a strategy deployed by the asymmetrically dividing bacterium Caulobacter crescentus where a regulatory protein is programmed to perform distinct functions at the opposing cell poles. We find that the CtrA proteolysis adaptor protein PopA assumes distinct oligomeric states at the two cell poles through asymmetrically distributed c-di-GMP: dimeric at the stalked pole and monomeric at the swarmer pole. Different polar organizing proteins at each cell pole recruit PopA where it interacts with and mediates the function of two molecular machines: the ClpXP degradation machinery at the stalked pole and the flagellar basal body at the swarmer pole. We discovered a binding partner of PopA at the swarmer cell pole that together with PopA regulates the length of the flagella filament. Our work demonstrates how a second messenger provides spatiotemporal cues to change the physical behavior of an effector protein, thereby facilitating asymmetry. [ABSTRACT FROM AUTHOR]

There is an increasing use of near-infrared lasers in biomedical applications operating in the spectrum between 1300 and 1400 nm. To corroborate and expand the existing safety data for skin exposure to lasers in this wavelength region, the in-vivo ED50 damage thresholds were determined in Guizhou miniature pigs for 1319-nm laser radiation. Exposure durations of 0.4, 1.0, and 3.0 s and 1/e² beam diameters of 0.98 and 1.96 cm were employed. Damage lesion determinations were performed at 1- and 24 h post exposure. The Bliss probit analysis was employed to establish the ED50 damage thresholds. Histopathological studies of skin damage were performed at 48 h after irradiation to reveal the damage characteristics. The skin damage thresholds at 1 h post exposure, given in peak radiant exposure, were 35.5, 36.1, and 37.1 J/cm² at exposure durations of 0.4, 1.0, and 3.0 s with the spot diameter of 0.98 cm, and 28.6 J/cm² at exposure duration of 3.0 s with the spot diameter of 1.96 cm. At 24 h post exposure, the ED50s increased slightly. Histologically, the thermal damage characteristics at the near-threshold level included gathering of the nuclear chromatin and cell vacuolation in the epidermis and deposition of blood cells in the capillary vessels. However, at the apparently above-threshold level, the damage characteristics included obvious stretching of the nuclear chromatin in the epidermis, closing of the capillary lumen, structural change of collagen fibers, and coagulative necrosis of the hair follicle cells. The damage induced by this laser could go deep into the fatty tissue. The obtained results may contribute to the knowledge base for the damage mechanisms and expand the database for the refinement of laser safety standards in the wavelength range of 1300 to 1400 nm. [ABSTRACT FROM AUTHOR]

The cell cycle-regulated methylation state of Caulobacter DNA mediates the temporal control of transcriptional activation of several key regulatory proteins. Temporally controlled synthesis of the CcrM DNA methyltransferase and Lon-mediated proteolysis restrict CcrM to a specific time in the cell cycle, thereby allowing the maintenance of the hemimethylated state of the chromosome during the progression of DNA replication. We determined that a chromosomal DNA-based platform stimulates CcrM degradation by Lon and that the CcrM C terminus both binds to its DNA substrate and is recognized by the Lon protease. Upon asymmetric cell division, swarmer and stalked progeny cells employ distinct mechanisms to control active CcrM. In progeny swarmer cells, CcrM is completely degraded by Lon before its differentiation into a replication-competent stalked cell later in the cell cycle. In progeny stalked cells, however, accumulated CcrM that has not been degraded before the immediate initiation of DNA replication is sequestered to the cell pole. Single-molecule imaging demonstrated physical anticorrelation between sequestered CcrM and chromosomal DNA, thus preventing DNA remethylation. The distinct control of available CcrM in progeny swarmer and stalked cells serves to protect the hemimethylated state of DNA during chromosome replication, enabling robustness of cell cycle progression. [ABSTRACT FROM AUTHOR]

Short tool service life is always a major concern when milling hard materials, such as Ni-based superalloy. In the current research of tool life optimization in multi-axis machining of freeform surfaces, the focus is mostly on choosing suitable cutting parameters and better application of coolant. In this paper, aiming at averaging the tool wear on the entire cutting edge and hence prolonging the tool service life, we report a study on how to generate a multilayer toolpath with a varying tool lead angle for multi-axis milling of an arbitrary freeform surface from an initial raw stock. The generated toolpath is guaranteed to be free of chatter, which is well known for its detrimental effect on the cutting edge. In this study, we first experimentally construct the chatter stability lobe diagram, which reveals the relationship between the lead angle and the cutting depth. With the chatter stability lobe diagram as the major constraint, we then generate the machining toolpath by selecting a proper pair of the best lead angle and cutting depth along the toolpath. While the proposed algorithm currently is restricted to the iso-planar type of toolpath, it can be adapted to other types of milling. The physical cutting experiments performed by us have convincingly confirmed the advantage of the proposed machining strategy as compared to the conventional constant lead angle and constant cutting depth strategy--in our tests the maximum wear on the cutting edge is reduced by as much as 39%. [ABSTRACT FROM AUTHOR]

We report the dynamic spatial organization of Caulobacter crescentus RNase E (RNA degradosome) and ribosomal protein L1 (ribosome) using 3D single-particle tracking and superresolution microscopy. RNase E formed clusters along the central axis of the cell' while weak clusters of ribosomal protein L1 were deployed throughout the cytoplasm. These results contrast with RNase E and ribosome distribution in Escherichia coli, where RNase E colocalizes with the cytoplasmic membrane and ribosomes accumulate in polar nucleoid-free zones. For both RNase E and ribosomes in Caulobacter, we observed a decrease in confinement and clustering upon transcription inhibition and subsequent depletion of nascent RNA' suggesting that RNA substrate availability for processing, degradation, and translation facilitates confinement and clustering. Importantly, RNase E cluster positions correlated with the subcellular location of chromosomal loci of two highly transcribed rRNA genes, suggesting that RNase E's function in rRNA processing occurs at the site of rRNA synthesis. Thus, components of the RNA degradosome and ribosome assembly are spatiotemporally organized in Caulobacter, with chromosomal readout serving as the template for this organization. [ABSTRACT FROM AUTHOR]

The corneal damage effects induced by 1319-nm transitional near-infrared laser have been investigated for years. However, the damage threshold dependence on exposure duration has not been revealed. The in vivo corneal damage thresholds (ED50s) were determined in New Zealand rabbits for 1319-nm laser radiation for exposure durations from 75 ms to 10 s. An additional corneal ED50 was determined at 1338 nm for a 5-ms exposure. The incident corneal irradiance diameter was fixed at 2 mm for all exposure conditions to avoid the influence of spot size on threshold. The ED50s given in terms of the corneal radiant exposure for exposure durations of 5 ms, 75 ms, 0.35 s, 2 s, and 10 s were 39.4, 51.5, 87.2, 156.3, and 311.1 J/cm², respectively. The 39.4 J/cm² was derived from the ED50 for 1338 nm (27.0 J/cm²). The ED50s for exposure durations of 75 ms to 10 s were correlated by a power law equation, ED50 128.9t 0.36 in J/cm², where t was the input in the unit of second, with correlation coefficient (R) of 0.997. Enough safe margins existed between the ED50s and the maximum permitted exposures from current laser safety standard. [ABSTRACT FROM AUTHOR]

Bacterial riboswitches couple small-molecule ligand binding to RNA conformational changes that widely regulate gene expression, rendering them potential targets for antibiotic intervention. Despite structural insights, the ligand-mediated folding mechanisms of riboswitches are still poorly understood. Using single-molecule fluorescence resonance energy transfer (smFRET), we have investigated the folding mechanism of an H-type pseudoknotted preQ1 riboswitch in dependence of Mg2+ and three ligands of distinct affinities. We show that, in the absence of Mg2+, both weakly and strongly bound ligands promote pseudoknot docking through an induced-fit mechanism. By contrast, addition of as low as 10 µM Mg2+ generally shifts docking toward conformational selection by stabilizing a folded-like conformation prior to ligand binding. Supporting evidence from transition-state analysis further highlights the particular importance of stacking interactions during induced-fit and of specific hydrogen bonds during conformational selection. Our mechanistic dissection provides unprecedented insights into the intricate synergy between ligand- and Mg2+-mediated RNA folding. [ABSTRACT FROM AUTHOR]

Flow dynamics in bubbling and turbulent fluidized beds containing both Geldart-A and B particles were investigated in this research. The numerical model was validated against experimental data, with a 6.16% average deviation. Results show that binary mixture segregation is enhanced as superficial gas velocity decreases. A larger flotsam packing ratio promotes homogeneous flotsam distribution; Second, bed density decreases with increasing bed height or superficial gas velocity. As the flotsam packing ratio decreases from 81.10 to 10.70%, bed density reaches the maximum at 41.50%, indicating the most severe volume contraction; Third, when the flotsam packing ratio decreases, the local mixing index's variances between upper and lower sections in dense phase first increases, then decreases, with stronger radial fluctuation detected; Fourth, as superficial gas velocity or flotsam packing ratio increases, the full mixing height ratio improves; Finally, multivariate correlations for dense phase bed expansion are established, yielding a 3.94% average error. [Display omitted] • A modified EMMS drag model was adopted to examine flow features in a bidisperse fluidized bed. • The quantified impacts of superficial gas velocity and packing state on flow are obtained. • Multivariate correlations for dense phase bed expansion were fitted with high accuracy. [ABSTRACT FROM AUTHOR]

Here we report synthesis and characterization of early transition-metal(TM)-substituted decaniobates as a continuation of our previous report of tetramethylammonium (TMA) salt of FeNb9 and NiNb9: TMA6[H2CrIIINb9O28]·14H2O (1, CrNb9), TMA8[MnIIINb9O28]·29H2O (2, MnNb9) and TMA7 [H2CoIINb9O28]· 25H2O (3, CoNb9). Among the TM-substituted decaniobates, CoNb9 or NiNb9 exhibit a higher photocatalytic H2 evolution activity in methanol-water mixtures than others. [ABSTRACT FROM AUTHOR]

A new tellurium-substituted Lindqvist-type polyoxoniobate [H2TeNb5O19]5- was synthesized as a tetramethylammonium salt. When irradiated with a Xe lamp, a water-methanol solution of this cluster showed exceptionally high H2-evolution activity suggesting cocatalysis by the hexaniobate cluster and metallic tellurium, both of which are formed as photodecomposition products. [ABSTRACT FROM AUTHOR]

In social interactions, people frequently encounter gain (i.e., all outcomes are gains from the status-quo) or loss (all outcomes are losses from the status-quo) social dilemmas, where their personal interests conflict with social interests. We ask whether there are any behavioral differences in social interactions when it comes to gains and losses. Using the Prisoner's Dilemma games, in three studies we observed that participants were less cooperative in the loss domain than in the gain domain. This effect was robust, not moderated by payoff amount (Study 1), cooperation index (Study 1), domain comparison (Studies 1 and 2), and personal loss aversion (Study 3). Social motive and belief explained this effect: compared to the gain domain, participants in the loss domain aroused more pro-self motive and less prosocial motive, and showed stronger beliefs that their partner would defect, which led them to cooperate less. These findings suggest that gain and loss domains affect individual motivation and belief, subsequently affecting strategic choices in social dilemmas. [ABSTRACT FROM AUTHOR]

Water oxidation on magnetic catalysts has generated significant interest due to the spin-polarization effect. Recent studies have revealed that the disappearance of magnetic domain wall upon magnetization is responsible for the observed oxygen evolution reaction (OER) enhancement. However, an atomic picture of the reaction pathway remains unclear, i.e., which reaction pathway benefits most from spin-polarization, the adsorbent evolution mechanism, the intermolecular mechanism (I2M), the lattice oxygen-mediated one, or more? Here, using three model catalysts with distinguished atomic chemistries of active sites, we are able to reveal the atomic-level mechanism. We found that spin-polarized OER mainly occurs at interconnected active sites, which favors direct coupling of neighboring ligand oxygens (I2M). Furthermore, our study reveals the crucial role of lattice oxygen participation in spin-polarized OER, significantly facilitating the coupling kinetics of neighboring oxygen radicals at active sites. [ABSTRACT FROM AUTHOR]

Climate change is a global concern for all life on our planet, including humans and plants. Plants' growth and development are significantly affected by abiotic stresses, including adverse temperature, inadequate or excess water availability, nutrient deficiency, and salinity. The circadian clock is a master regulator of numerous developmental and metabolic processes in plants. In an effort to identify new clock-related genes and outputs through bioinformatic analysis, we have revealed that CIRCADIAN CLOCK ASSOCIATED 1 (CCA1) and LATE ELONGATED HYPOCOTYL (LHY) play a crucial role in regulating a wide range of abiotic stress responses and target ABSCISIC ACID RESPONSIVE ELEMENTS-BINDING FACTOR3 (ABF3), a key transcription factor in the plant hormone Abscisic acid (ABA)-signaling pathway. Specifically, we found that CCA1 and LHY regulate the expression of ABF3 under diel conditions, as well as seed germination under salinity. Conversely, ABF3 controls the expression of core clock genes and orchestrates the circadian period in a stress-responsive manner. ABF3 delivers the stress signal to the central oscillator by binding to the promoter of CCA1 and LHY. Overall, our study uncovers the reciprocal regulation between ABF3 and CCA1/LHY and molecular mechanisms underlying the interaction between the circadian clock and abiotic stress. This finding may aid in developing molecular and genetic solutions for plants to survive and thrive in the face of climate change. [ABSTRACT FROM AUTHOR]

A high rate of 2.23 mmol h-1 g-1 (quantum efficiency of 6.67% at 400 nm) for visible light driven photocatalytic H2 evolution can be achieved with g-C3N4 by alkalization of the solution to a pH of 13.3, due to accelerated transfer of photoholes to the sacrificial donor. [ABSTRACT FROM AUTHOR]

Superresolution fluorescence microscopy and cryogenic electron tomography (CET) are powerful imaging methods for exploring the subcellular organization of biomolecules. Superresolution fluorescence microscopy based on covalent labeling highlights specific proteins and has sufficient sensitivity to observe single fluorescent molecules, but the reconstructions lack detailed cellular context. CET has molecular-scale resolution but lacks specific and nonperturbative intracellular labeling techniques. Here, we describe an imaging scheme that correlates cryogenic single-molecule fluorescence localizations with CET reconstructions. Our approach achieves singlemolecule localizations with an average lateral precision of 9 nm, and a relative registration error between the set of localizations and CET reconstruction of ~30 nm. We illustrate the workflow by annotating the positions of three proteins in the bacterium Caulobacter crescentus: McpA, PopZ, and SpmX. McpA, which forms a part of the chemoreceptor array, acts as a validation structure by being visible under both imaging modalities. In contrast, PopZ and SpmX cannot be directly identified in CET. While not directly discernable, PopZ fills a region at the cell poles that is devoid of electron-dense ribosomes. We annotate the position of PopZ with singlemolecule localizations and confirm its position within the ribosome excluded region. We further use the locations of PopZ to provide context for localizations of SpmX, a low-copy integral membrane protein sequestered by PopZ as part of a signaling pathway that leads to an asymmetric cell division. Our correlative approach reveals that SpmX localizes along one side of the cell pole and its extent closely matches that of the PopZ region. [ABSTRACT FROM AUTHOR]

Fertilization mode affects soil quality and ecological health. The effects of four fertilization regimens on lignocellulose content, readily degradable carbohydrate decomposition, and potential microbial functions in the topsoil of a wheat--maize rotation system between 2012 and 2017 were investigated. The fertilization regimens of control (control NFNB), high chemical fertilizer (HCF), high biochar plus low chemical fertilizer (HBLCF), and biochar-based fertilizer (BBF) were compared on soil fundamental properties, microbial structure, and potential function in soil carbohydrate degradation based on metagenome analysis. The diversity of carbohydrate-active enzyme genes in the topsoil microbial consortia in the four trials was primarily distributed within the ten ecologically most dominant phyla. Application of BBF was associated with the lowest decline in total nitrogen and P2O5 (2012-2017: 6.5% and 28.1%, respectively) and the most effective carbohydrate decomposition (2015-2017: 67.0% for cellulose and 59.9% for readily degradable carbohydrate). Carbohydrate transport and metabolism accounted for 6.0% of reads assigned functional classification under the BBF regimen. These findings reveal the ecologically functional diversity of topsoil microorganisms and suggest BBF application as a promising strategy for sustainable agriculture and beneficial to soil health. [ABSTRACT FROM AUTHOR]

A nationwide survey of organic fertilizer was carried out in China, and 263 samples were collected to be analyzed for maturity indices (moisture content (MC), pH, electrical conductivity (EC), E4/E6, and germination index (GI)) and 7 heavy metals (Cu, Zn, Cd, Pb, Cr, As and Ni). The MC, pH, EC, E4/E6 and GI showed large variations among the organic fertilizer samples with ranges of 6.9%-66.68%, 4.40-9.19, 0.76-13.38 mS/cm, 1.07-9.40, and 10%-150%, respectively. The concentrations of 7 heavy metals (Cu, Zn, Cd, Pb, As, Cr, Ni) were also with large variations at7.53-580.4, 0-2818, 0.02-149.3, 0 (not detected)-1321, 0.14-26.9, 3.70-1237, and 0 (not detected)-214.6 mg/kg dry weight. Compared with the limit values of the Chinese standard for organic fertilizers (NY525-2012), 9.51%, 73.4%, 3.19%, and 3.04% of the samples exceeded the limit values of Cd, Pb, As and Cr, respectively. No limits have been set for Cu, Zn and Ni in China, and 35.0%, 13.3% and 16.7% of the samples exceeded the Cu, Zn and Ni limits for composts in Germany, respectively. Monte Carlo simulations indicated that with the continuous application of organic fertilizer, Cu, Zn, Cd, Pb and Cr would accumulate to the risk control standard for soil contamination of agricultural land (GB15618-2018) within a relatively short period. It is urgent to establish suitable limits of heavy metals in organic fertilizer in China to control the risk of heavy metal pollution in agricultural land. [ABSTRACT FROM AUTHOR]

[Objectives] To observe the protective effect of Cordyceps cicadae polysaccharides on acute liver injury induced by D-galactosamine (D-GlaN) in mice, ad to explore its mechanism. [Methods] Seventy-five male Kunming mice were randomly and evenly divided into 5 groups according to the digital table method: normal group (CK) (injected intraperitoneal with saline solution), model group (injected intraperitoneall with D-GlaN), low-dose C. cicadae polysaccharides group (administered with 0.5 g/kg of C. cicadae polysaccharides solution by gavage), middle-dose C. cicadae polysaccharides group (administered with 1.0 g/kg of C. cicadae polysaccharides solution by gavage) ad high-dose C. cicadae polysaccharides group (administered with 2.0 g/kg of C. cicadae polysaccharides solution by gavage). Ater 12 d of administration, the liver histopathological score, liver homogenate indexes (superoxide dismutase, SOD; malondialdehyde, MDA; glutathione peroxidase, GSH-Px; nitric oxide, NO) and serum markers (aspartate transaminase, AST; alanine transaminase, ALT; alkaline phosphatase, ALP; cholinesterase, CHE) of mice in each group were detected. The expression levels of nuclear factor-κB (NF-κB) and tumor necrosis factor-α (TNF-α) in liver tissues were detected by immunohistochemistry. [Results] The liver histopathological score and the MDA, NO, AST, ALT, ALP, NF-κB and TNF-α levels were significantly higher (P<0.05) and the SOD, GSH-Px and CHE levels were significantly lower (P<0.05) in the model group compared with the normal group. Compared with those in the model group, the liver tissue histopathological scores in the low-, middle- and high-dose C. cicadae polysaccharides groups were H significantly reduced (P<0.05). With the increase of treatment dose, the liver tissue histopathological scores showed a significant decrease (P<0.05). Compared with the model group, the levels of MDA, NO, AST, ALT, ALP, NF-κB and TNF-α were significantly lower (P <0.05), and the levels of SOD, GSH-Px and CHE were significantly higher (P<0.05) in the low-, middle- and high-dose C. cicadae polysaccharides groups. With the increase of treatment dose, the levels of MDA, NO, AST, ALT, ALP, NF-κB and TNF-α declined significantly (P<0.05), while the levels of SOD, GSH-Px and CHE rose signiicanty (P<0.05). [Conclusions] C. cicadae polysaccharides have a significant protective effect on D-GlaN-induced acute liver injury in mice in a dose-dependent manner, and the mechanism may be related to the inhibition of NF-κB inflammatory signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: The major challenge of chemotherapy is the disease resistance for many lung cancer patients. Integrated microfluidic systems offer many desirable characteristics and can be used in cellular biological analysis. This work aimed to study the correlation between the expression of Glucose Regulated Protein-78 (GRP78) and the resistance to anticancer drug VP-16 in human lung squamous carcinoma cell line SK-MES-1 using an integrated microfluidic gradient chip device. We used A23187, a GRP78 inducer, with a gradient concentration in the upstream network of the device to induce the expression of GRP78 in the cells cultured in the downstream before the addition of VP-16. The expression of GRP78 was detected by immunofluorescence, the apoptosis for the cells treated by VP-16 was assessed morphologically by 4′,6-diamidino-2-phenylindole (DAPI) staining. The results indicated that the expressions of GRP78 increased greatly for the cells under the induction of A23187 with a dose-depended manner, while the percentage of apoptotic cells decreased significantly after being treated by VP-16. Our results from this study confirmed the role of GRP78 played in the chemotherapy resistance to VP-16 in SK-MES-1 cell line, suggesting that the integrated microfluidic systems may be an unique approach for characterizing the cellular responses. [Copyright &y& Elsevier]