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1.
ChemSusChem ; 17(14): e202301708, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38436577

RESUMO

Traditional polybenzoxazine thermosets cannot be reprocessed or recycled due to the permanent crosslinked networks. The dynamic exchangeable characteristics of imine bonds can impart the networks with reprocessabilities and recyclabilities. This study reported a weldable, reprocessable, and water-resistant polybenzoxazine vitrimer (C-ABZ) crosslinked by dynamic imine bonds. It was synthesized through a condensation reaction between an aldehyde-containing benzoxazine oligomer (O-ABZ) and 1,12-dodecanediamine. The resulting C-ABZ was able to be welded and reprocessed due to the dynamic exchange of imine bonds. The tensile strengths of the welded C-ABZ and the reprocessed C-ABZ after three cycles of hot-pressing were 76.7, 81.3, 70.8, and 58.1 Mpa, with corresponding tensile strength recovery ratios of 74.1 %, 78.6 %, 68.4 %, and 56.1 %, respectively. Furthermore, the polybenzoxazine backbone significantly improved the water resistance of the imine bonds. After immersing in water for 30 days at room temperature, the weight gain of C-ABZ was less than 1 % with corresponding tensile strength and tensile strength retention ratio of 59.5 Mpa and 57.5 %, respectively. Although the heat resistance of C-ABZ decreased slightly with increased hot-pressing cycles, a glass transition temperature (Tg, tanδ) of 150 °C was retained after the third hot-pressing. Overall, these findings demonstrate that the C-ABZ possesses excellent comprehensive performances.

2.
Diabetes Care ; 47(1): 160-168, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37943529

RESUMO

OBJECTIVE: We conducted a randomized, double-blind, placebo-controlled phase 2 trial to evaluate the efficacy and safety of mazdutide, a once-weekly glucagon-like peptide 1 and glucagon receptor dual agonist, in Chinese patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: Adults with type 2 diabetes inadequately controlled with diet and exercise alone or with stable metformin (glycated hemoglobin A1c [HbA1c] 7.0-10.5% [53-91 mmol/mol]) were randomly assigned to receive 3 mg mazdutide (n = 51), 4.5 mg mazdutide (n = 49), 6 mg mazdutide (n = 49), 1.5 mg open-label dulaglutide (n = 50), or placebo (n = 51) subcutaneously for 20 weeks. The primary outcome was change in HbA1c from baseline to week 20. RESULTS: Mean changes in HbA1c from baseline to week 20 ranged from -1.41% to -1.67% with mazdutide (-1.35% with dulaglutide and 0.03% with placebo; all P < 0.0001 vs. placebo). Mean percent changes in body weight from baseline to week 20 were dose dependent and up to -7.1% with mazdutide (-2.7% with dulaglutide and -1.4% with placebo). At week 20, participants receiving mazdutide were more likely to achieve HbA1c targets of <7.0% (53 mmol/mol) and ≤6.5% (48 mmol/mol) and body weight loss from baseline of ≥5% and ≥10% compared with placebo-treated participants. The most common adverse events with mazdutide included diarrhea (36%), decreased appetite (29%), nausea (23%), vomiting (14%), and hypoglycemia (10% [8% with placebo]). CONCLUSIONS: In Chinese patients with type 2 diabetes, mazdutide dosed up to 6 mg was generally safe and demonstrated clinically meaningful HbA1c and body weight reductions.


Assuntos
Diabetes Mellitus Tipo 2 , Adulto , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Hemoglobinas Glicadas , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Peso Corporal , Método Duplo-Cego , China , Resultado do Tratamento , Quimioterapia Combinada
3.
Sensors (Basel) ; 16(8)2016 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-27527170

RESUMO

Research on smart homes (SHs) has increased significantly in recent years because of the convenience provided by having an assisted living environment. The functions of SHs as mentioned in previous studies, particularly safety services, are seldom discussed or mentioned. Thus, this study proposes a semantic approach with decision support for safety service in SH management. The focus of this contribution is to explore a context awareness and reasoning approach for risk recognition in SH that enables the proper decision support for flexible safety service provision. The framework of SH based on a wireless sensor network is described from the perspective of neighbourhood management. This approach is based on the integration of semantic knowledge in which a reasoner can make decisions about risk recognition and safety service. We present a management ontology for a SH and relevant monitoring contextual information, which considers its suitability in a pervasive computing environment and is service-oriented. We also propose a rule-based reasoning method to provide decision support through reasoning techniques and context-awareness. A system prototype is developed to evaluate the feasibility, time response and extendibility of the approach. The evaluation of our approach shows that it is more effective in daily risk event recognition. The decisions for service provision are shown to be accurate.


Assuntos
Moradias Assistidas , Tecnologia sem Fio , Sistemas Computacionais , Humanos , Semântica
4.
Polymers (Basel) ; 8(12)2016 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-30974714

RESUMO

Two novel cycloalkoxy silane compounds (ED1 and ED2) were synthesized and used as the external electron donors (EEDs) in Ziegler⁻Natta catalysts with diethyl 2,3-diisopropylsuccinate as internal electron donor. The results indicated that the Ziegler⁻Natta catalysts using ED1 and ED2 as EEDs had high catalytic activities and good stereoselectivities. The melt flow rate (MFR) and gel permeation chromatography (GPC) results revealed that the obtained polypropylene has higher MFR and lower average molecular weights than the commercial EED cyclohexyl methyl dimethoxysilane. The differential scanning calorimetry (DSC) results indicated that new isospecific active centers formed after the introduction of new external donors. The work implied that the novel EEDs could improve the hydrogen sensitivities of the catalyst system and obtain polymers with high melt flow rate.

5.
Polymers (Basel) ; 8(3)2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30979172

RESUMO

A series of N-acetyl-O-(ω-alkenyl)-l-tyrosine ethyl esters were synthesized by the reaction of vinyl bromides (4-bromo-1-butene, 6-bromo-1-hexene, 8-bromo-1-octene and 10-bromo-1-decene) with N-acetyl-l-tyrosine ethyl ester. ¹H NMR, elemental analysis, FT-IR, and mass spectra were performed for these N-acetyl-O-(ω-alkenyl)-l-tyrosine ethyl esters. The novel titanium complex can catalyze the copolymerization of ethylene and N-acetyl-O-(ω-alkenyl)-l-tyrosine ethyl esters efficiently and the highest catalytic activity was up to 6.86 × 104 gP·(molTi)-1·h-1. The structures and properties of the obtained copolymers were characterized by FT-IR, (¹H)13C NMR, GPC, DSC, and water contact angle. The results indicated that the obtained copolymers had a uniformly high average molecular weight of 2.85 × 105 g·mol-1 and a high incorporation ratio of N-acetyl-O-(but-3-enyl)-l-tyrosine ethyl ester of 2.65 mol % within the copolymer chain. The units of the comonomer were isolated within the copolymer chains. The insertion of the polar comonomer into a copolymer chain can effectively improve the hydrophilicity of a copolymer.

6.
Sensors (Basel) ; 15(11): 29273-96, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26610496

RESUMO

Online monitoring and water quality analysis of lakes are urgently needed. A feasible and effective approach is to use a Wireless Sensor Network (WSN). Lake water environments, like other real world environments, present many changing and unpredictable situations. To ensure flexibility in such an environment, the WSN node has to be prepared to deal with varying situations. This paper presents a WSN self-configuration approach for lake water quality monitoring. The approach is based on the integration of a semantic framework, where a reasoner can make decisions on the configuration of WSN services. We present a WSN ontology and the relevant water quality monitoring context information, which considers its suitability in a pervasive computing environment. We also propose a rule-based reasoning engine that is used to conduct decision support through reasoning techniques and context-awareness. To evaluate the approach, we conduct usability experiments and performance benchmarks.

7.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): m351-2, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589752

RESUMO

The mol-ecular structure of the title compound, [Al(CH(3))(2)(C(22)H(26)NO)], displays a monomer with the Al(III) atom in a distorted tetra-hedral environment defined by two methyl groups and the N and O atoms of the chelating ketiminate anion. The O-Al-N bite angle of the chelating ligand is 94.14 (9)°. The O-C-C-C-N backbone of the ligand is nearly coplanar (r.m.s. deviation = 0.029 Å) and the Al atom deviates significantly from the mean plane by 0.525 (3) Å. In the crystal, weak inter-molecular C-H⋯O inter-actions are observed.

8.
Inorg Chem ; 43(21): 6596-9, 2004 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-15476356

RESUMO

Treatment of Pd(2)Cl(2)(CNC(6)H(3)Me(2)-2,6)(4) (1) with Mo(2)(O(2)CCF(3))(4) (2) in dichloromethane afforded an infinite zigzag chain [[Pd(2)Cl(2)(CNC(6)H(3)Me(2)-2,6)(4)][Mo(2)(O(2)CCF(3))(4)]](n) (3), where two metal-metal bonded dinuclear Pd-Pd and Mo-Mo units were bridged by chloro atoms. The Mo-Mo distance (2.1312(3) A) of 3 is significantly elongated compared to that of 2 (2.090(4) A) and lies in the range of that of the quadruple Mo-Mo bonded complexes. Such elongation might be attributed to the axial donation of the chloro atoms of the Pd-Pd unit to the Mo-Mo moiety.

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