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Purpose: Anastomotic recurrence leads to poor prognosis in patients with Siewert II or III adenocarcinoma who undergo radical gastrectomy and do not receive neoadjuvant therapy. We aimed to establish a prognostic model to evaluate the risk of postoperative anastomotic recurrence in patients with Siewert II or III adenocarcinoma who did not receive neoadjuvant therapy. Methods: We included 366 patients with Siewert II or III adenocarcinoma who were treated with radical gastrectomy without neoadjuvant therapy at Fujian Provincial Hospital (FPH) between 2012 and 2018 as the development cohort. Cox regression was used to verify prognostic factors for anastomotic recurrence, and a nomogram was established. The nomogram was externally validated using a combined cohort of two external centers. Patients were classified into high- or low-risk groups according to the diagnostic threshold and nomogram scores, and recurrence-related survival analysis was analyzed. Results: The average age was 64.6 years, and 285 patients were male. All surgeries were successfully performed (185 open vs 181 laparoscopic). The 3-year anastomotic recurrence rate was significantly lower in the low-risk group (3.5% vs 18.8%, P < 0.001). The predictive performance was verified in the external validation cohort. This model better stratified patient survival than the American Joint Committee on Cancer (AJCC) TNM staging system. Conclusions: This novel nomogram with surgical margin, postoperative tumor node metastasis (pTNM) stage, and neural invasion as prognostic factors has a significant predictive performance for the risk of anastomotic recurrence after radical gastrectomy in patients with Siewert II or III adenocarcinoma. [ABSTRACT FROM AUTHOR]

Transition metal-catalyzed asymmetric hydrofunctionalizations of unsaturated bonds via π-ƞ3 substitution have emerged as a reliable method to construct stereogenic centers, and mainly rely on the use of heteroatom-based or carbon nucleophiles bearing acidic C-H bonds. In comparison, sp2 carbon nucleophiles are generally not under consideration because of enormous challenges in cleaving corresponding inert sp2 C-H bonds. Here, we report a protocol to achieve asymmetric formal sp2 hydrocarbonations, including hydroalkenylation, hydroallenylation and hydroketenimination of both 1,3-dienes and alkynes via hydroalkylation and Wittig reaction cascade. A series of unachievable motifs via hydrofunctionalizations, such as di-, tri- and tetra-substituted alkenes, di-, tri- and tetra-substituted allenes, and tri-substituted ketenimines in allyl skeletons are all facilely constructed in high regio-, diastereo- and enantioselectivities with this cascade design. Stereodivergent synthesis of all four stereoisomers of 1,4-diene bearing a stereocenter and Z/E-controllable olefin unit highlights the power of present protocol. An interesting mechanistic feature is revealed that alkyne actually undergoes hydrocarbonation via the formation of conjugated diene intermediate, different from conventional viewpoint that the hydrofunctionalization of alkynes only involves allene species. Sp2 carbon nucleophiles are generally not considered for transition metal-catalyzed asymmetric hydrofunctionalizations of unsaturated bonds due to challenges in cleaving corresponding inert sp2 C-H bonds. Here, the authors report a protocol to achieve asymmetric formal sp2 hydrocarbonations, including hydroalkenylation, hydroallenylation and hydroketenimination of both 1,3-dienes and alkynes via hydroalkylation and Wittig reaction cascade [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, effect of PEDOT:PSS content on structure and properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/poly(vinyl alcohol) (PVA) composite conducting fiber was systematically investigated for the first time. PEDOT:PSS/PVA composite conducting fibers with various PEDOT:PSS loadings were successfully fabricated via wet-spinning technique. Correlation between PEDOT:PSS loading and performance of composite fibers was investigated by analyzing changes in chemical constitution, morphology, thermal property, conductivity, and tensile property of composite fibers. Formation of hydrogen bonding interactions was observed between PVA matrix and PEDOT:PSS conducting filler, and the interaction was enhanced with increasing PEDOT:PSS loading. As PEDOT:PSS loading increased in composite fiber, fiber conductivity increased monotonically, and surface morphology of composite fibers became regularly circular. Young's modulus and tensile strength of composite fibers also increased with increasing PEDOT:PSS loading, while elongation at break decreased. In addition, thermal stability of composite fibers improved with increasing PEDOT:PSS loading. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present study, novel strong and conductive blended fibers composed of poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) and polyvinyl alcohol (PVA) were successfully fabricated via a wet-spinning process using spinning formulation prepared by doping DMSO into PVA/PEDOT:PSS aqueous solution. The effects of DMSO on structure and properties of PVA/PEDOT:PSS blended fibers were systematically investigated in detail by analyzing the changes in electrical conductivity, aggregation structure, conformational PEDOT chains, morphology and mechanical properties. The results showed that doping of DMSO induced significant conformational changes in PEDOT chains which in turn led to significant enhancement in electrical conductivity and smoother surface morphology as well as better mechanical properties of PVA/PEDOT:PSS blended fibers. The resultant DMSO-doped PVA/PEDOT:PSS blended conductive fibers exhibited an enhanced electrical conductivity up to 21.16 S cm. In addition, as the doping concentration of DMSO increased, the surface of blended fibers became less fluted and smoother. The Young's modulus and tensile strength increased from 3.5 GPa and 115 MPa to 4.95 GPa and 145 MPa respectively, while the elongation at break decreased from 25 % to 17 %. [ABSTRACT FROM AUTHOR]

Amorphous silica was modified by doping with titania through a surface sol–gel process and applied as the support for depositing gold. These doped silica-supported gold catalysts were tested in the selective cyclohexane oxidation to cyclohexanone and cyclohexanol using oxygen. Under the oxidation conditions of 150 °C, 1.5 MPa and 3 h, a selectivity of 91.7% for cyclohexanone and cyclohexanol could be reached over the gold catalyst, affording a cyclohexane conversion of 8.4% and a turnover frequency up to 40,133 per hour. Moreover, the catalytic activity and selectivity could be well retained in 4 recycling oxidation reactions, showing a high stability of the gold catalyst supported on titania-doped silica. [ABSTRACT FROM AUTHOR]

The selective oxidation of cyclohexane to cyclohexanone and cyclohexanol has been investigated over Au/Al2O3 catalysts using molecular oxygen in a solvent-free system. The catalysts were prepared by a modified direct anionic exchange method and characterized by AAS, N2 adsorption and TEM. The results showed that the catalytic performance of Au/Al2O3 is very high in terms of turnover frequency. Moreover, the nano-size effect of gold is also reported in the reaction. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates on the biological components of nonalkaloid portions of Ervatamia yunnanensis. The study used a plant material from Xishuangbanna, Yunnan province identified as stems of Ervatamia yunnanensis Tsiang which were extracted and suspended in 2% hydrochloric (HCL) solution. It says that the fractions were subjected to chromatography and 14 compounds, including flavonoids, vanillin, and lignans, were isolated.

In this study, blend fibers composed of poly(vinyl alcohol) and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) were prepared via wet-spinning technology. Ethylene glycol (EG) vapor annealing was employed to improve the electrical conductivity and tensile properties of blend fibers. The effects of EG vapor annealing on structures and properties of blend fibers were investigated in detail by analyzing the changes in chemical constituent and structure, molecular structure, surface morphology, surface chemical composition, electrical conductivity, and tensile properties. FTIR spectroscopy indicates that EG vapor annealing does not change the chemical constituent and structure of blend fibers. Raman spectroscopy shows that vapor annealing leads to conformational changes of PEDOT chains from benzoid structure to quinoid structure. AFM and SEM images show that surface morphology of blend fibers become smoother after vapor annealing. XPS measurement shows that EG vapor annealing induces significant phase separation between PEDOT and PSS, forming an enriched PSS layer on the surface of blend fibers, thus leading to a thinner insulating PSS layer between PEDOT grains. This conformational change is beneficial to improve the electrical conductivity of blend fibers. The resultant blend fiber reached conductivity up to 20.4 S cm−1. The mechanical properties of blend fibers were also improved by EG vapor annealing, with the Young’s modulus and tensile strength increasing from 3.6 GPa and 112 MPa to 4.4 GPa and 132.7 MPa, respectively.In this study, blend fibers composed of poly(vinyl alcohol) and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) were prepared via wet-spinning technology. Ethylene glycol (EG) vapor annealing was employed to improve the electrical conductivity and tensile properties of blend fibers. The effects of EG vapor annealing on structures and properties of blend fibers were investigated in detail by analyzing the changes in chemical constituent and structure, molecular structure, surface morphology, surface chemical composition, electrical conductivity, and tensile properties. FTIR spectroscopy indicates that EG vapor annealing does not change the chemical constituent and structure of blend fibers. Raman spectroscopy shows that vapor annealing leads to conformational changes of PEDOT chains from benzoid structure to quinoid structure. AFM and SEM images show that surface morphology of blend fibers become smoother after vapor annealing. XPS measurement shows that EG vapor annealing induces significant phase separation between PEDOT and PSS, forming an enriched PSS layer on the surface of blend fibers, thus leading to a thinner insulating PSS layer between PEDOT grains. This conformational change is beneficial to improve the electrical conductivity of blend fibers. The resultant blend fiber reached conductivity up to 20.4 S cm−1. The mechanical properties of blend fibers were also improved by EG vapor annealing, with the Young’s modulus and tensile strength increasing from 3.6 GPa and 112 MPa to 4.4 GPa and 132.7 MPa, respectively.In this study, blend fibers composed of poly(vinyl alcohol) and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) were prepared via wet-spinning technology. Ethylene glycol (EG) vapor annealing was employed to improve the electrical conductivity and tensile properties of blend fibers. The effects of EG vapor annealing on structures and properties of blend fibers were investigated in detail by analyzing the changes in chemical constituent and structure, molecular structure, surface morphology, surface chemical composition, electrical conductivity, and tensile properties. FTIR spectroscopy indicates that EG vapor annealing does not change the chemical constituent and structure of blend fibers. Raman spectroscopy shows that vapor annealing leads to conformational changes of PEDOT chains from benzoid structure to quinoid structure. AFM and SEM images show that surface morphology of blend fibers become smoother after vapor annealing. XPS measurement shows that EG vapor annealing induces significant phase separation between PEDOT and PSS, forming an enriched PSS layer on the surface of blend fibers, thus leading to a thinner insulating PSS layer between PEDOT grains. This conformational change is beneficial to improve the electrical conductivity of blend fibers. The resultant blend fiber reached conductivity up to 20.4 S cm−1. The mechanical properties of blend fibers were also improved by EG vapor annealing, with the Young’s modulus and tensile strength increasing from 3.6 GPa and 112 MPa to 4.4 GPa and 132.7 MPa, respectively. [ABSTRACT FROM AUTHOR]