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FUS-mediated alternative splicing and METTL3-regulated RNA methylation play crucial roles in RNA processing. The purpose of this study was to investigate the interactive roles of FUS and METTL3 in gastric cancer (GC) progression. RNA sequencing data were obtained from the TCGA-STAD dataset. Differentially expressed genes (DEGs) were analyzed across groups stratified by the medians of FUS, METTL3, and NEAT1, respectively. Endoplasmic reticulum (ER) stress markers PERK, IRE1, pIRE1, Bip, and CHOP, as well as related apoptosis stress markers PARP, cleaved-PARP, (Cleaved) Caspase 7, and (Cleaved) Caspase 3, were assessed through western blotting. Alternative splicing and N6-methyladenosine (m(6)A) methylation of specific genes were detected with MeRIP-PCR. Finally, in vivo experiments were conducted using nude mice bearing sh-FUS-transfected HGC27 xenograft tumors. FUS and METTL3 expression levels were elevated in GC tissues. A significant overlap of DEGs was observed between the FUS- and METTL3-stratified groups. These overlapping DEGs were predominantly enriched in mRNA processing and protein processing in the ER. ER stress and apoptosis were induced by sh-FUS or sh-METTL3, which was further enhanced by ER stress inducer tunicamycin in both MKN45 and HGC27 cells. Similarly, DEGs for NEAT1 high- and low-expressed groups were enriched in protein processing in the ER and spliceosome. To a lesser extent, ER stress was also induced by sh-NEAT1 and enhanced by tunicamycin in HGC27 cells. Furthermore, sh-FUS or sh-METTL3 influenced alternative splicing and methylation of specific mRNAs, including FUS, NEAT1, PCNA, MCM2, and BIRC5. Tumor progression was inhibited by sh-FUS in mice, and ER stress and apoptosis were induced, which were further enhanced by tunicamycin. FUS and METTL3 collaborate to facilitate RNA maturation. Inhibiting FUS or METTL3 promoted ER stress and apoptosis and inhibited progression in GC. Aberrant levels of FUS and METTL3 can evoke endoplasmic reticulum (ER) stress and apoptosis by generating splicing and methylation variants of mRNAs in gastric cancer, supporting the therapeutic potential of inducing ER stress [ABSTRACT FROM AUTHOR]

In the geological field, recognizing rock thin section images under a microscope is of great significance to geological research and mineral resources exploration. Compared with other images, the rock thin section microscope image has complex features and rich information. When classifying for them, the redundant information and features that are useless for classification tasks will affect the model classification effect. Thus this paper proposes a rock image classification algorithm based on depth residuals shrinkage network and attention mechanism to suppress the useless information. The subnetwork of obtaining threshold value is improved, and the global maximum pooling of features is added as information representation, and the soft threshold function is improved by adding the weight coefficient which is based on attention mechanism to distinguish the importance of different features. Moreover, three rock thin section microscopic image classification algorithms fusing multidimensional information are designed, and the orthogonal polarized image and single polarized image of rock thin section are input as the base data, which make full use of the multidimensional information of rock thin section microscopic image. This study used 20,242 images of 12 kinds of rock thin sections as samples to train and verify the above method. The results show that the method proposed in this paper can effectively improve the recognition accuracy of rock thin section images under a microscope. [ABSTRACT FROM AUTHOR]

Objective : Our study aimed to investigate the correlations between microstructural changes of cingulum and patients with mild cognitive impairment (MCI) by diffusion kurtosis imaging (DKI) technique. Method: A total of 104 patients with cerebral small vessel diseases (cSVD) were retrospectively enrolled in this study. According to Montreal Cognitive Assessment Scale (MoCA) scores, these patients were divided into MCI group (n = 59) and non-MCI group (n = 45). The general clinical data was collected and analyzed. The regions of interests (ROIs) were selected for investigation in cingulum. The values of DKI parameters were measured in each ROI and compared between the two groups, the correlations between DKI parameters and MoCA scores were examined. Results: Compared to non-MCI group, MCI patients had more severe white matter hyperintensities (WMHs) (P = 0.038) and lower MoCA scores (P < 0.01). MCI patients showed significantly decreased fractional anisotropy (FA), axial kurtosis (AK), mean kurtosis (MK), radial kurtosis (RK), and kurtosis fractional anisotropy (KFA) in the left cingulum in the cingulated cortex (CgC) region (all P < 0.0125). In the left CgC region, FA, AK, MK, RK, and KFA were positively correlated with MoCA scores (r = 0.348, 0.409, 0.310, 0.441, 0.422, all P < 0.001). Meanwhile, FA, AK, MK, RK, and KFA were also positively correlated with MoCA scores (r = 0.338, 0.352, 0.289, 0.380, 0.370, all P < 0.001) in the right CgC region. Conclusion: DKI technique could be used to explore the microstructural changes of cingulum in MCI patients and DKI-derived parameters might be feasible to evaluate MCI patients. [ABSTRACT FROM AUTHOR]

In this paper, comparative experiments were conducted to investigate the relationship between the welding procedure used (autogenous and non-autogenous welding) and the mechanical properties in association with the corresponding microstructures of laser beam welded AA2915 plates without the removal of surface oxide layer. The results showed that significant reduction in quantity and size of hydrogen-induced pores could be obtained by using conventional filler wire AA4047 (Al12Si) in comparison with the autogenous welds which led to relatively higher mechanical properties with the tensile strength approaching 59.5% of the base metal along the rolling orientation. The morphologies and distribution feature of the solidified structures of the experimental workpieces were analyzed in the light of 3D finite element model. Deep etching was incorporated to induce the contrast for clear observation of secondary phases. The results indicate that the grain structure of non-autogenous welded joints was more stable against the changes in welding process parameters due to the relatively higher constitutional undercooling at the growth front of the solidifying grains. The addition of Si was believed to decrease the absorbed hydrogen volume via diluting the content of Cu and Li in the welded seam, thereby decreasing the porosity and improving the mechanical properties. [ABSTRACT FROM AUTHOR]

This paper presents a method to improve the laser bonding joint strength between carbon fiber reinforced thermoplastic composite (CFRTP) and aluminum alloy (Al). In this method, the CFRTP with preset aluminum alloy sheet is attained by the compression molding method after the aluminum alloy sheet is preset between the polyetheretherketone (PEEK) and carbon cloth. The CFRTP with preset aluminum alloy sheet is connected to the aluminum alloy by laser heat source, and the maximum load of the joint can reach 4264 N. Microstructure and fracture surface morphology of joint are observed and analyzed. The results indicate that the interface of the preset aluminum alloy sheet and CFRTP reveals an extensive diffusion of elements compared with the interface of aluminum alloy and CFRTP due to the effect of hot pressing. The fracture failure mode of the lap structure between aluminum alloy and CFRTP is mixed fracture with adhesion fracture as the main component. The fracture position of preset aluminum alloy sheet and aluminum alloy lap structure is observed near the weld seam fusion line, and numerous dimples are found on the fracture surface of aluminum alloy. The increase in joint bonding force is mainly attributed to the collective effect of two lap structures; during the stretching process, the interface between aluminum alloy and CFRTP first undergoes fracture, and then, preset aluminum alloy sheet undergoes plastic fracture failure. [ABSTRACT FROM AUTHOR]

Restarting of antiplatelet therapy (AT) for patients with a history of intracerebral hemorrhage (ICH) is still a clinical dilemma in China. We aimed to investigate the association between low-dose AT and the long-term clinical outcome in Chinese ICH patients. A total of 312 patients with a history of ICH were retrospectively enrolled and followed. The ischemic vascular events, recurrent ICH, and all-cause death were reviewed retrospectively. We explored the predictors of ischemic vascular events and recurrent ICH from all patients using Cox proportional hazard regression model. One hundred fifty-one (48.4%) patients were treated with low-dose AT, and the median duration of follow-up was 4.0 years (interquartile range, 2.5–5 years). Compared to 30 (19.8%) of 151 participants who restarted low-dose AT had ischemic vascular events, 51 (31.7%) of 161 participants who did not receive AT showed ischemic vascular events (p=0.025). Eighteen (11.9%) of 151 participants treated with low-dose AT had recurrent ICH and 21 (13.0%) of 161 in non-AT participants (p=0.830). Cox regression analysis also showed that diabetes mellitus was an independent risk factor for ischemic vascular events (p=0.029). Uncontrolled blood pressure (BP) was independently associated with the risk for both ischemic vascular events (p=0.025) and recurrent ICH (p=0.001). Atrial fibrillation (AF) was an independent risk factor for recurrent ICH among patients with a history of ICH (p=0.018). In a Chinese population of patients with predominantly deep, mild to moderate severity ICH, restarting of low-dose AT at a median of 6.2 months was associated with a lower risk of ischemic vascular events without increased risk of recurrent ICH. [ABSTRACT FROM AUTHOR]

Dual laser-beam bilateral synchronous welding is introduced to produce the 2.5 mm thick 5A90 Al–Li alloy T-joint. The grain morphology and grain size of weld metal (WM) in the T-joint are analyzed and calculated. The tensile experiment, scanning electron microscopy and energy disperse spectroscopy are respectively employed to study the tensile strength, fracture morphology and chemical composition of the T-joint. The results reveal that when the laser power is increased from 2500 to 3000 W, the grain sizes of fine-grained layers and columnar dendrites near the fusion line are significantly reduced. Conversely, that of equiaxed dendrites at the WM center is not sensitive to the variety of laser power. Moreover, the degree of elemental segregation in WM near the fusion line is also aggravated with the increasing of the laser power. The tensile strength of the T-joint with the laser power of 2500 W is significantly higher than that with the laser power of 3000 W. The tensile fracture locations are occurred in the weld toe with obvious pores, shear dimples and tear ridges, which are the typical characteristics of ductile fracture. Besides, the chemical compositions of the second phase particles in the WM are more sensitive to than the variation of laser power compared with that of the matrix. [ABSTRACT FROM AUTHOR]

The aim of this study is to characterize demographic and morphologic characteristics of aneurysms located in the anterior communicating artery (ACoA) and to investigate possible associations between these characteristics and aneurysm rupture. We investigated 112 consecutive patients (72 ruptured and 40 unruptured) with ACoA aneurysms from a single-center database. The effects of demographic and morphologic characteristics on the risk of rupture in ACoA aneurysms were tested using univariate and multivariate logistic regression analyses, respectively. We found that larger size, greater size ratio, larger flow angle, irregular shape, and smoking of the patient were associated with the rupture of ACoA aneurysms based on univariate analysis. Size ratio (OR = 3.890, P = 0.003), irregular shape (OR = 1.068, P = 0.001), flow angle (OR = 1.054, P = 0.001), and current smoking (OR = 4.435, P = 0.009) were the strongest factors related to ruptured ACoA aneurysms based on multivariate logistic regression analysis. The areas under the curves for the flow angle and size ratio were 0.742 (95% CI 0.646–0.838; P = 0.001) and 0.736 (95% CI 0.621–0.796; P = 0.001), respectively. The strongest risk factors for rupture include size ratio, irregular shape, flow angle, and current smoking. These features should be taken into consideration to aid in the prediction of the rupture risk of ACoA aneurysms. [ABSTRACT FROM AUTHOR]

Stereospecific polymerization of polar olefins has always been an attractive but challenging project because the Lewis basic polar groups of monomers are usually poisonous to the Lewis acidic metal centers of the catalysts. In this contribution, thiophene-fused cyclopentadienyl scandium complexes 1—3 were successfully synthesized. Combined with alkylaluminium and organoborate, these complexes showed extremely low activity and no selectivity for 1-hexene polymerization. Surprisingly, highly stereo-selective coordination polymerization of unprotected polar 4-methylthio-1-butene has been achieved in high activity for the first time under the same polymerization conditions. High-molecular-weight (Mn=110×103) and perfectly syn-diotactic (rrrr>99%) poly(4-methylthio-1-butene) (P(MTB)) was afforded. Thus the methylthio-group-assisted mechanism that the unmasked methylthio group promoted the polymerization through σ-π chelation to the active scandium center together with the vinyl group was proposed. Moreover, the methylsulfonyl functionalized syndiotactic poly(1-butene) was also easily prepared by the oxidation of P(MTB). These results provided a new route for the synthesis of functionalized stereo-regular polyolefins. [ABSTRACT FROM AUTHOR]

The aryldiimine NCN-pincer stabilized neodymium dichloride combined with aluminum alkyls established a new type of homogeneous binary neutral Ziegler-Natta catalyst system. This system exhibited high activity and high cis-1,4 selectivity for the polymerization of isoprene ( T = 20 °C, 98.2%; T = −20 °C, > 99%). Such catalytic performances remained under a broad range of polymerization temperatures and monomer-to-neodymium ratios (from 500 to 8000), reaching high number-average molecular weight ( M = 1582 kg/mol) and relatively narrow molecular weight distribution (PDI = 1.68), which was, however, influenced by the amount and bulkiness of aluminum alkyls. Dynamic investigation of the polymerization was performed, which showed the number-average molecular weight of the resultant polyisoprene had an almost linear correlation with the conversion, suggesting, in some degree, the polymerization with this catalytic system was controllable. [ABSTRACT FROM AUTHOR]