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Two different sizes of graphene oxide (GO) produced by the Hummers method had been incorporated into epoxy resins and used to fabricate GO modified carbon fiber reinforced epoxy resin composites (GO/CF/EP) by compression molding method, and the composite material was processed under damp and heat conditions. The modification effects of dry and wet composite materials were investigated through interlayer shear performance, dynamic thermomechanical properties and microscopic morphology. The results indicate that GO has a good improvement on the interlaminar shear strength and glass transition temperature of composite materials. In the dry state at room temperature, two sizes of GO have basically the same improvement effect on the interlaminar shear strength of the composite. With the increase of GO content, the small size of GO makes the hygrothermal interlaminar shear strength of composites decrease faster. When the GO content is 0.1%(mass fraction, the same as below), the improvement of the interlaminar shear performance of the composite material is better, however, the glass transition temperature of the composite material is better when the GO content is 0.2%. With the increase of GO content, the exothermic peak of the GO-EP composite resin matrix shifts to low temperature, and the small size of GO shortens the gel time of the composite resin. The micro-morphology analysis shows the presence of GO is beneficial for increasing the crack propagation path during the failure of composite material, thereby more conducive to the dissipate the crack tip energy by the material.

Objective: To explore the microstructural damage of extrapyramidal system gray matter nuclei in Parkinson disease (PD) using diffusion kurtosis imaging (DKI).Materials and Methods: We enrolled 35 clinically confirmed PD patients and 23 healthy volunteers. All patients underwent MR examination with conventional MRI scan sequences and an additional DKI sequence. We subsequently reconstructed the DKI raw images and analyzed the data. A radiologist in our hospital collected the Mini-Mental State Examination (MMSE) score of all subjects.Results: In the PD group, the mean kurtosis and axial kurtosis level decreased in the red nucleus (RN) and thalamus; the radial kurtosis increased in the substantia nigra (SN) and globus pallidus (GP). Fractional anisotropy decreased in the putamen. The largest area under the ROC curve of mean diffusion in GP was 0.811. Most kurtosis parameters demonstrated a positive correlation with the MMSE score, while several diffusion parameters showed a negative correlation with the same.Conclusion: DKI can qualitatively distinguish PD from healthy controls; furthermore, DKI-derived parameters can quantitatively evaluate the modifications of microstructures in extrapyramidal system gray matter nucleus in PD.

Four optimizing methods of equipment cost structure were detailedly analyzed based on their theories. The strengths and weaknesses of the four optimizing methods were analyzed and compared each other. And the characteristics of system dynamics were introduced. It was found that the weaknesses of the four optimizing methods were just made up by the characteristics of system dynamics. It was put forward that system dynamics is better than the four methods in optimizing equipment cost structure at the moment. This viewpoint not only enriches the categories of optimizing methods for equipment cost structure, but also explores a new way for optimizing equipment cost structure in practice.

Burkholderia semiarida has only been reported as a plant pathogen causing onion sour skin (1). The Burkholderia genus encompasses >120 bacterial species that are typically reported to inhabit soil and [...]

Objective To analyze the factors affecting the bowel preparation effect of polyethylene glycol electrolyte powder （PEG-ELP） combined with dimethicone in hospitalized patients. Methods Clinical data of bowel preparation of 200 hospitalized patients who underwent colonoscopy were retrospectively analyzed. The influencing factors of bowel cleaning effect were analyzed. Results Univariate analysis showed that hypertension，dyslipidemia，positive urine ketone body，and colonoscopy scheduled in the afternoon were influencing factors of the cleanliness of bowel preparation，respectively （all P < 0.05）. Multivariate regression analysis indicated that dyslipidemia（OR = 2.312，95%CI（1.245，4.293），P = 0.008），hypertension （OR = 2.270，95%CI（1.193，4.318），P = 0.013），and colonoscopy scheduled in the afternoon （OR = 2.377，95%CI（1.279，4.416），P = 0.006） were the risk factors for low quality of bowel preparation，respectively. Conclusion For hospitalized patients receiving bowel preparation with PEG-ELP combined with dimethicone，hypertension，dyslipidemia and colonoscopy scheduled in the afternoon are the independent risk factors affecting bowel preparation before colonoscopy.

Allene (C3H4) gas is produced and separated on million-metric-ton scale per year during petroleum refining but is rarely employed in organic synthesis. Meanwhile, the addition of an allyl group (C3H5) to ketones is among the most common and prototypical reactions in synthetic chemistry. Herein, we report that the combination of allene gas with inexpensive and environmentally benign hydrosilanes, such as PMHS, can serve as a replacement for stoichiometric quantities of allylmetal reagents, which are required in most enantioselective ketone allylation reactions. This process is catalyzed by copper salts and commercially available ligands, operates without specialized equipment or pressurization, and tolerates a broad range of functional groups. Furthermore, the exceptional chemoselectivity of this catalyst system enables industrially relevant C3 hydrocarbon mixtures of allene with methylacetylene and propylene to be applied directly.

Background and Hypothesis The gut-brain axis plays important roles in both gastrointestinal diseases (GI diseases) and schizophrenia (SCZ). Moreover, both GI diseases and SCZ exhibit notable abnormalities in brain subcortical volumes. However, the genetic mechanisms underlying the comorbidity of these diseases and the shared alterations in brain subcortical volumes remain unclear. Study Design Using the genome-wide association studies data of SCZ, 14 brain subcortical volumes, and 8 GI diseases, the global polygenic overlap and local genetic correlations were identified, as well as the shared genetic variants among those phenotypes. Furthermore, we conducted multi-trait colocalization analyses to bolster our findings. Functional annotations, cell-type enrichment, and protein-protein interaction (PPI) analyses were carried out to reveal the critical etiology and pathology mechanisms. Study Results The global polygenic overlap and local genetic correlations informed the close relationships between SCZ and both GI diseases and brain subcortical volumes. Moreover, 84 unique lead-shared variants were identified. The associated genes were linked to vital biological processes within the immune system. Additionally, significant correlations were observed with key immune cells and the PPI analysis identified several histone-associated hub genes. These findings highlighted the pivotal roles played by the immune system for both SCZ and GI diseases, along with the shared alterations in brain subcortical volumes. Conclusions These findings revealed the shared genetic architecture contributing to SCZ and GI diseases, as well as their shared alterations in brain subcortical volumes. These insights have substantial implications for the concurrent development of intervention and therapy targets for these diseases. [ABSTRACT FROM AUTHOR]

A long-standing challenge in synthetic chemistry is the development of the transamidation reaction. This process, which involves the conversion of one amide to another, is typically plagued by unfavourable kinetic and thermodynamic factors. Although some advances have been made with regard to the transamidation of primary amide substrates, secondary amide transamidation has remained elusive. Here we present a simple two-step approach that allows for the elusive overall transformation to take place using non-precious metal catalysis. The methodology proceeds under exceptionally mild reaction conditions and is tolerant of amino-acid-derived nucleophiles. In addition to overcoming the classic problem of secondary amide transamidation, our studies expand the growing repertoire of new transformations mediated by base metal catalysis.

In this paper, we present a novel multi-target feature selection algorithm that incorporates adaptive graph learning and target correlations. Specifically, our proposed approach introduces the low-rank constraint on the regression matrix, allowing us to model both inter-target and input–output relationships within a unified framework. To preserve the similarity structure of the samples and mitigate the influence of noise and outliers, we learn a graph matrix that captures the induced sample similarity. Furthermore, we introduce a manifold regularizer to maintain the global target correlations, ensuring the preservation of the overall target relationship during subsequent learning processes. To solve the final objective function, we also propose an optimization algorithm. Through extensive experiments on eight real-world datasets, we demonstrate that our proposed method outperforms state-of-the-art multi-target feature selection techniques. [ABSTRACT FROM AUTHOR]

Protein tyrosine kinase 6 (PTK6), also known as breast tumor kinase (BRK), serves as a non-receptor intracellular tyrosine kinase within the Src kinases family. Structurally resembling other Src kinases, PTK6 possesses an Src homology 3 (SH3) domain, an Src homology 2 (SH2) domain, and a tyrosine kinase domain (SH1). While considerable efforts have been dedicated to designing PTK6 inhibitors targeting the SH1 domain, which is responsible for kinase activity in various pathways, it has been observed that solely inhibiting the SH1 domain does not effectively suppress PTK6 activity. Subsequent investigations have revealed the involvement of SH2 and SH3 domains in intramolecular and substrate binding interactions, which are crucial for PTK6 function. Consequently, the identification of PTK6 inhibitors targeting not only the SH1 domain but also the SH2 and SH3 domains becomes imperative. Through an in silico structural-based virtual screening approach, incorporating drug repurposing and a consensus docking approach, we have successfully identified four potential ligands capable of concurrently inhibiting the tyrosine kinase domain and SH2/SH3 domains of PT6K simultaneously. This finding suggests potential pathways for therapeutic interventions in PTK6 inhibition. [ABSTRACT FROM AUTHOR]

Global routing plays a crucial role in printed circuit board (PCB) design and affects the cost of the design significantly. Conventional methods based on rectangular grids have some limitations, whereas this paper introduces a new algorithm that employs a triangular grid model, which offers a more efficient solution to the problem. Firstly, we present a technique to sort all unconnected two-pin nets. Next, a triangular grid graph is constructed to represent the routing resources on the printed circuit board. Finally, we use the concept of maximum flow to identify the paths for global routing and apply detailed routing for the completion of wires. Results from experiments demonstrate that our algorithm is faster than two state-of-the-art routers and does not have any design rule violations for all industrial PCB instances. [ABSTRACT FROM AUTHOR]

A strategy for optimizing the rolling resistance, wet skid and cut resistance of reinforced rubber simultaneously using a supramolecular filler is demonstrated. A β-alanine trimer-grafted Styrene Butadiene Rubber (A3-SBR) pristine polymer was designed and mechanically mixed with commercially available styrene butadiene rubber to help the dispersion of a β-alanine trimer (A3) supramolecular filler in the rubber matrix. To increase the miscibility of A3-SBR with other rubber components during mechanical mixing, the pristine polymer was saturated with ethanol before mixing. The mixture was vulcanized using a conventional rubber processing method. The morphology of the assembles of the A3 supramolecular filler in the rubber matrix was studied by Differential Scanning Calorimetry (DSC) and Transmission Electron Microscopy (TEM). The Differential Scanning Calorimetry study showed that the melting temperature of β-sheet crystals in the vulcanizates was around 179 °C and was broad. The melting temperature was similar to that of the pristine polymer, and the broad melting peak likely suggests that the size of the crystals is not uniform. The Transmission Electron Microscopy study revealed that after mixing the pristine polymer with SBR, some β-sheet crystals were rod-like with several tens of nanometers and some β-sheet crystals were particulate with low aspect ratios. Tensile testing with pre-cut specimens showed that the vulcanizate containing A3-SBR was more cut-resistant than the one that did not contain A3-SBR, especially at a large cut size. The rolling resistance and wet skid were predicted by dynamic mechanical analysis (DMA). DMA tests showed that the vulcanizates containing A3-SBR were significantly less hysteretic at 60 °C and more hysteretic at 0 °C based on loss factor. Overall, the "magic triangle" was expanded by optimizing the rolling resistance, wet-skid, and cut resistance simultaneously using a β-alanine trimer supramolecular filler. The Payne effect also became less severe after introducing the β-alanine trimer supramolecular filler into the system. [ABSTRACT FROM AUTHOR]