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1.
Angew Chem Int Ed Engl ; 60(14): 7710-7718, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33368927

RESUMO

Aryl-ether-free anion-exchange ionomers (AEIs) and membranes (AEMs) have become an important benchmark to address the insufficient durability and power-density issues associated with AEM fuel cells (AEMFCs). Here, we present aliphatic chain-containing poly(diphenyl-terphenyl piperidinium) (PDTP) copolymers to reduce the phenyl content and adsorption of AEIs and to increase the mechanical properties of AEMs. Specifically, PDTP AEMs possess excellent mechanical properties (storage modulus>1800 MPa, tensile strength>70 MPa), H2 fuel-barrier properties (<10 Barrer), good ion conductivity, and ex-situ stability. Meanwhile, PDTP AEIs with low phenyl content and high-water permeability display excellent peak power densities (PPDs). The present AEMFCs reach outstanding PPDs of 2.58 W cm-2 (>7.6 A cm-2 current density) and 1.38 W cm-2 at 80 °C in H2 /O2 and H2 /air, respectively, along with a specific power (PPD/catalyst loading) over 8 W mg-1 , which is the highest record for Pt-based AEMFCs so far.

2.
Am J Emerg Med ; 32(6): 529-34, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24612594

RESUMO

INTRODUCTION: This study was conducted to examine the characteristics of intentional fall injuries and the factors associated with their prognosis. METHODS: The study included 8992 patients with unintentional falls from a height (nonintentional group) and 144 patients with intentional falls from a height (intentional group). General and clinical characteristics were compared between the 2 groups. Intentional fall cases were divided into severe and nonsevere groups, and the factors associated with severe injury were evaluated by comparing these groups. RESULTS: The most common age group was younger than 14 years in the nonintentional group and between 30 and 44 years old in the intentional group. For the nonintentional group, 65% of the patients were male, and 48% were male in the intentional group. Fall heights of more than 4 m were most common in the intentional group. Discharge was the most common result in the nonintentional group; however, death before arrival at the emergency department (ED) or during ED treatment occurred in 54.9% of patients in the intentional group. In the severe injury group within the intentional group, patients were older, and the height of the fall was higher. Factors associated with severe injury in the intentional group included being a high school graduate rather than a college graduate and greater fall height. CONCLUSION: The risk of severe injury increased with fall height in the intentional group, and a high school level of education rather than a college level of education was associated with more severe injury.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Tentativa de Suicídio/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Acidentes por Quedas/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Estudos Retrospectivos , Fatores Sexuais , Ferimentos e Lesões/etiologia , Adulto Jovem
3.
J Med Food ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023772

RESUMO

This study investigated the antiobesity effects of black ginger extract (BGE) in high-fat diet (HFD)-induced obese mice. Mice were divided into six groups: normal diet control (NC, AIN-93G normal diet), 60% HFD control (HFD), HFD containing metformin at 250 mg/kg b.w. (Met, positive control), and HFD containing BGE at 5, 10, or 20 mg/kg b.w. for 15 weeks. BGE administration significantly prevented HFD-induced increases in weight gain, organ weight, and adipose tissue mass. Furthermore, it resulted in decreased adipogenesis and lipogenesis-related factors, including phosphorylated mitogen-activated protein kinase, peroxisome proliferator-activated receptor gamma, CCAAT/enhancer-binding proteins, sterol regulatory element-binding protein 1, phosphorylated cAMP response element-binding protein, glucose-6-phosphate dehydrogenase, fatty acid synthase, dephosphorylated ATP-citrate lyase, dephosphorylated acetyl-CoA carboxylase, and lipoprotein lipase, in white adipose tissues. Moreover, BGE administration enhanced lipolysis in white adipose tissue, as evidenced by elevated levels of adipose triglyceride lipase, phosphorylated hormone-sensitive lipase, and protein kinase A, along with reduced levels of perilipin and phosphodiesterase 3B. BGE induced thermogenesis in brown adipose tissues, as reflected by the increased expression of AMP-activated protein kinase, uncoupling protein 1, and carnitine palmitoyltransferase 1 and decreased levels of fatty acid-binding protein 4. In conclusion, this study provides comprehensive evidence supporting the antiobesity effects of BGE, elucidating the underlying molecular mechanisms involved in preventing weight gain, suppressing adipogenesis, promoting lipolysis, and stimulating thermogenesis. These findings suggest the potential therapeutic utility of BGE in combating obesity and associated metabolic disorders (KHGASP-2023-034).

4.
Curr Microbiol ; 65(6): 701-10, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22961036

RESUMO

This study was undertaken to determine whether cyclic AMP (cAMP) or cAMP-receptor protein (CRP) modulates the activity of the autoinducer (AI)-2-mediated quorum sensing (QS) system in response to glucose availability in Vibrio vulnificus. A mutation in crp impaired V. vulnificus growth, decreased AI-2 production, and repressed the expression of smcR encoding the master regulator SmcR (a Vibrio harveyi LuxR homolog) of the AI-2-QS system, and these changes were prevented by in trans complementation of wild-type crp. Furthermore, glucose repressed smcR expression in the presence of CRP but not in its absence. A mutation in cyaA encoding adenylate cyclase, which is required for cAMP synthesis, also impaired V. vulnificus growth and repressed smcR expression, and these changes were recovered by in trans complementation of wild-type cyaA. These results indicate that cAMP or CRP modulates the AI-2-QS system in response to glucose availability in V. vulnificus, demonstrating the presence of a connection between catabolite repression and quorum sensing in V. vulnificus.


Assuntos
Proteína Receptora de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Regulação Bacteriana da Expressão Gênica , Homosserina/análogos & derivados , Lactonas/farmacologia , Percepção de Quorum/efeitos dos fármacos , Vibrio vulnificus/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Meios de Cultura , AMP Cíclico/genética , Proteína Receptora de AMP Cíclico/genética , Glucose/metabolismo , Homosserina/metabolismo , Homosserina/farmacologia , Humanos , Lactonas/metabolismo , Mutação , Transativadores/genética , Transativadores/metabolismo , Vibrio vulnificus/genética , Vibrio vulnificus/metabolismo
5.
Nat Commun ; 12(1): 2367, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888709

RESUMO

Low-cost anion exchange membrane fuel cells have been investigated as a promising alternative to proton exchange membrane fuel cells for the last decade. The major barriers to the viability of anion exchange membrane fuel cells are their unsatisfactory key components-anion exchange ionomers and membranes. Here, we present a series of durable poly(fluorenyl aryl piperidinium) ionomers and membranes where the membranes possess high OH- conductivity of 208 mS cm-1 at 80 °C, low H2 permeability, excellent mechanical properties (84.5 MPa TS), and 2000 h ex-situ durability in 1 M NaOH at 80 °C, while the ionomers have high water vapor permeability and low phenyl adsorption. Based on our rational design of poly(fluorenyl aryl piperidinium) membranes and ionomers, we demonstrate alkaline fuel cell performances of 2.34 W cm-2 in H2-O2 and 1.25 W cm-2 in H2-air (CO2-free) at 80 °C. The present cells can be operated stably under a 0.2 A cm-2 current density for ~200 h.

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