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1.
Small ; : e2400046, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441356

RESUMO

The development of cost-effective and high-performance oxygen evolution reaction (OER) catalysts is a significant challenge. This study presents the synthesis of binder-free NiFe@NiFe layered double hydroxide (NNF) via one-pot electrodeposition on carbon paper and Ni foam at high current densities. The presence of Ni sulfate residues on the prepared NNF is also investigated. The findings indicate that Ni sulfate significantly improves OER performance and durability. The sulfate content can be controlled by varying the method and duration of washing. NNF prepared through dipping (NNF-D) exhibits outstanding OER activity with a low overpotential of 241 mV, which is 25 mV lower than that of NNF washed for 60 s (NNF-W-60 s) at 10 mA cm-2 in 1 m KOH. Furthermore, density functional theory analyses indicate that the Ni sulfate residue helps modify the electronic structure, thereby optimizing the binding strength of *OOH. This synthetic strategy is expected to inspire the development of next-generation catalysts utilizing various adsorbates.

2.
J Neurophysiol ; 126(5): 1698-1709, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34644124

RESUMO

We investigated the role of task constraints on interpersonal interactions. Twenty-one pairs of coworkers performed a finger force production task on force sensors placed at two ends of a seesaw-like apparatus and matched a combined target force of 20 N for 23 s over 10 trials. There were two experimental conditions: 1) FIXED: the seesaw apparatus was mechanically held in place so that the only task constraint was to match the 20 N resultant force, and 2) MOVING: the lever in the apparatus was allowed to rotate freely around its fulcrum, acting like a seesaw, so an additional task constraint to (implicitly) balance the resultant moment was added. We hypothesized that the additional task constraint of moment stabilization imposed on the MOVING condition would deteriorate task performance compared with the FIXED condition; however, this was rejected, as the performance of the force matching task was similar between two conditions. We also hypothesized that the central nervous systems (CNSs) would employ distinct coworking strategies or interpersonal motor synergy (IPMS) between conditions to satisfy different task constraints, which was supported by our results. Negative covariance between coworker's forces in the FIXED condition suggested a force stabilization strategy, whereas positive covariance in the MOVING condition suggested a moment stabilization strategy, implying that independent CNSs adopt distinct IPMSs depending on task constraints. We speculate that in the absence of a central neural controller, shared visual and mechanical connections between coworkers may suffice to trigger modulations in the cerebellum of each CNS to satisfy competing task constraints.NEW & NOTEWORTHY To the best of our knowledge, this is the first study to investigate the coworking behavior or IPMS when an additional task constraint is imposed. Our proposed analytical framework quantifies IPMS and allows for investigating variability in offline (i.e., across multiple repetitions) and online (i.e., across time) control, which is novel in coworking research. Understanding variability while performing a task is essential, as repeating a task is not always possible, as in therapeutic contexts.


Assuntos
Comportamento Cooperativo , Atividade Motora/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Feminino , Dedos , Humanos , Masculino , Interface Usuário-Computador , Adulto Jovem
3.
Yonsei Med J ; 55(5): 1273-80, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25048485

RESUMO

PURPOSE: To evaluate the influence of preoperative mechanical bowel preparation (MBP) based on the occurrence of anastomosis leakage, surgical site infection (SSI), and severity of surgical complication when performing elective colorectal surgery. MATERIALS AND METHODS: MBP and non-MBP patients were matched using propensity score. The outcomes were evaluated according to tumor location such as right- (n=84) and left-sided colon (n=50) and rectum (n=100). In the non-MBP group, patients with right-sided colon cancer did not receive any preparation, and patients with both left-sided colon and rectal cancers were given one rectal enema before surgery. RESULTS: In the right-sided colon surgery, there was no anastomosis leakage. SSI occurred in 2 (4.8%) and 4 patients (9.5%) in the non-MBP and MBP groups, respectively. In the left-sided colon cancer surgery, there was one anastomosis leakage (4.0%) in each group. SSI occurred in none in the rectal enema group and in 2 patients (8.0%) in the MBP group. In the rectal cancer surgery, there were 5 anastomosis leakages (10.0%) in the rectal enema group and 2 (4.0%) in the MBP group. SSI occurred in 3 patients (6.0%) in each groups. Severe surgical complications (Grade III, IV, or V) based on Dindo-Clavien classification, occurred in 7 patients (14.0%) in the rectal enema group and 1 patient (2.0%) in the MBP group (p=0.03). CONCLUSION: Right- and left-sided colon cancer surgery can be performed safely without MBP. In rectal cancer surgery, rectal enema only before surgery seems to be dangerous because of the higher rate of severe postoperative complications.


Assuntos
Cirurgia Colorretal/métodos , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Cuidados Pré-Operatórios/efeitos adversos , Pontuação de Propensão , Idoso , Anastomose Cirúrgica , Cirurgia Colorretal/efeitos adversos , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios/métodos , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/epidemiologia , Resultado do Tratamento
4.
Int J Surg Case Rep ; 4(11): 1038-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24121050

RESUMO

INTRODUCTION: Stercoral perforation of the colon has rarely been reported. Only 3 cases of stercoral perforation of the colon proximal to an end colostomy have been reported. We present two cases of stercoral perforation of the colon in end colostomy patients. PRESENTATION OF CASE: A 70-year-old man who had undergone abdomino-perineal excision for anal cancer was referred for left lower quadrant pain and fever. Stercoral perforation was discovered along the distal descending colon, proximal to the end sigmoid colostomy. The patient underwent segmental resection of the colon and revision of the stoma and was discharged on postoperative day 32. A 71-year-old woman who had undergone abdomino-perineal excision for distal rectal cancer with preoperative chemoradiation presented fever with 2 days of low abdominal pain. The patient had sacral bone and lung metastases from rectal cancer and suffered from chronic constipation. Stercoral perforation was found around the sigmoid colon, just proximal to the end sigmoid colostomy. The patient underwent simple repair of the perforated colon through the parastomal incision. On postoperative day 8, leakage occurred at the repair site. Segmental resection of the colon and revision of the stoma were performed. She was discharged 44 days after the initial surgery. DISCUSSION: Segmental resection of the perforated colon, rather than simple repair, appears to improve postoperative outcomes. CONCLUSION: As the number of cancer survivors increases, appropriate management of constipation is important to prevent stercoral perforation during follow-up.

5.
Appl Microbiol Biotechnol ; 97(18): 8151-61, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23615738

RESUMO

This study aimed to develop an economically viable enzyme for the optimal production of steviol (S) from stevioside (ST). Of 9 commercially available glycosidases tested, S-producing ß-glucosidase (SPGase) was selected and purified 74-fold from Penicillium decumbens naringinase by a three-step column chromatography procedure. The 121-kDa protein was stable at pH 2.3-6.0 and at 40-60 °C. Hydrolysis of ST by SPGase produced rubusoside (R), steviolbioside (SteB), steviol mono-glucoside (SMG), and S, as determined by HPLC, HPLC-MS, and (1)H- and (13)C-nuclear magnetic resonance. SPGase showed higher activity toward steviol mono-glucosyl ester, ST, R, and SMG than other ß-linked glucobioses. The optimal conditions for S production (30 mM, 64 % yield) were 47 mM ST and 43 µl of SPGase at pH 4.0 and 55 °C. This is the first report detailing the production of S from ST hydrolysis by a novel ß-glucosidase, which may be useful for the pharmaceutical and agricultural areas.


Assuntos
Diterpenos do Tipo Caurano/biossíntese , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Penicillium/enzimologia , beta-Glucosidase/química , beta-Glucosidase/metabolismo , Diterpenos do Tipo Caurano/metabolismo , Estabilidade Enzimática , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Glucosídeos/metabolismo , Cinética , Penicillium/genética , Penicillium/isolamento & purificação , Penicillium/metabolismo , Especificidade por Substrato , beta-Glucosidase/genética , beta-Glucosidase/isolamento & purificação
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