A highly enantioselective conjugate addition reaction of 3-substituted benzothiophen-2-ones to 2-phthalimidoacrylates has been developed using a bifunctional tertiary-amine thiourea catalyst. A ...number of chiral 3-substituted benzothiophen-2-one compounds were obtained with excellent yields (up to 99%) and very good stereoselectivities (up to >19 : 1 dr and up to 92% ee). The reaction was proved to be an efficient strategy for the synthesis of enantioenriched α-amino acid derivatives with 1,3-nonadjacent stereogenic centers.
The Box–Behnken design response surface methodology (BBD-RSM) was utilized to model and optimize electrodialysis process for lead (Pb(II)) removal from seaweed extracts. The experiments were ...conducted with three influential variables including the operational voltage and initial lead concentration and flow rate using a full 24 factorial experimental design. According to the ridge and canonical analysis, the effect of major factors on Pb(II) removal in ED process follows the order: operational voltage > flow rate > initial lead concentration. Under the optimized parameters, the lead removal of 76.52% was acquired which showed good agreement with model predicted (75.45%) result. The feasibility of RSM model for lead removal response was verified by analysis of variance (ANOVA), which indicated a good reproducibility and fit of the experimental data with a high value coefficient (R2= 0.9945 and R2adj = 0.9874). The results suggested that electrodialysis with Box–Behnken design response surface methodology is regarded as the promising technology for lead removal from seaweed extracts.
Phenol, zinc acetate dihydrate and paraformaldehyde are firstly performed to synthesize thermoplastic phenolic resin (PR), then phenylboronic acid (PBA) and other two boron compounds (4-hydroxymethyl ...phenylboronic acid & boronic acid) are introduced to fabricate the boron-containing thermoplastic phenolic resins (BPRs). The corresponding molecular structure, softening points, thermal decomposition temperature and char yield ratio of the BPRs are characterized and investigated by FTIR, NMR, XPS and TGA. Compared to pure thermoplastic PR, all the BPRs present relatively higher softening points, more excellent thermal decomposition temperature and higher char yield values. BPR-a exhibits the optimal thermal decomposition temperature (
T
5
of 317.4 °C) and char yield ratio at 800 °C (69.6 %).
Dynamic disasters in Chinese coal mines pose a significant threat to coal productivity. Thus, a thorough understanding of the deformation and failure processes of coal is necessary. In this study, ...the energy dis-sipation rate is proposed as a novel indicator of coal deformation and failure under static and dynamic compressive loads. The relationship between stress-strain, uniaxial compressive strength, displacement rate, loading rate, fractal dimension, and energy dissipation rate was investigated through experiments conducted using the MTS C60 tests (static loads) and split Hopkinson pressure bar system (dynamic loads). The results show that the energy dissipation rate peaks are associated with stress drop during coal deformation, and also positively related to the uniaxial compressive strength. A higher displacement rate of quasi-static loads leads to an initial increase and then a decrease in energy dissipation rate, whereas a higher loading rate of dynamic loads results in larger energy dissipation rate. Theoretical analysis indi-cates that a sudden increase in energy dissipation rate suggests partial fracture occurring within coal under both quasi-static and dynamic loads. Hence, the energy dissipation rate is an essential indicator of partial fracture and final failure within coal, as well as a prospective precursor for catastrophic failure in coal mine.
Finding new immune-related biomarkers is one of the promising research directions for tumor immunotherapy. The
gene could stimulate the WNT pathway and regulate the progression of various tumors. ...Recent studies have partially revealed the relationship between
and tumor immunity, but the correlation and underlying mechanisms in pan-cancer remain obscure. Thus, we conducted this study aiming to characterize the prognostic value and immunological portrait of
in cancer.
The data obtained from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), and Cancer Cell Line Encyclopedia (CCLE) databases was utilized to analyze
expression levels by Kruskal-Wallis test and correlation to prognosis by Cox regression test and Kaplan-Meier test, while the data was also used to study the association between
expression and immune microenvironment, immune neoantigens, immune checkpoints, tumor mutational burden (TMB), and microsatellite instability (MSI) in pan-cancer. Gene set enrichment analysis (GSEA) was used to clarify the relevant signaling pathways. The R package was used for data analysis and to create the plots.
The pan-cancer analysis revealed that the expression level of
is generally elevated in most tumors (19/34, 55.88%), and high
expression was correlated with poor prognosis in esophageal carcinoma (ESCA, P<0.05), low-grade glioma (LGG, P<0.01), adrenocortical carcinoma (ACC, P<0.01), pancreatic adenocarcinoma (PAAD, P<0.01), and head and neck squamous cell carcinoma (HNSC, P<0.05). In addition,
expression was positively associated with immune infiltration, stromal score, and immune checkpoints in most cancers, and correlated to immune neoantigens, TMB, and MSI. Finally, GSEA indicated that
is implicated in the transforming growth factor β (TGFβ), Notch, and Hedgehog signaling pathways, which may be related to tumor immunity.
The expression of
is elevated in most tumors and associated with tumor prognosis. Furthermore,
is associated with tumor immunity and may be an immunological biomarker in cancer.
The surface treatment of high modulus poly(
p
-phenylene-2,6-benzobisoxazole) (HMPBO) fibers was performed by using a solution of polyphosphoric acid (PPA)/absolute alcohol (EtOH) (1:1, vol:vol) ...under ultrasonic vibration. The chemical compositions, crystallinity, and surface morphologies of HMPBO fibers were characterized by contact angles, XRD, XPS, TGA, and SEM. Results showed that the hydrophilicity of treated HMPBO fibers was improved, and the contact angles between treated HMPBO fibers and water were decreased. The treated HMPBO fibers exhibited the slight reduction in the single fiber pull-out strength and crystallinity.
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