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The hydrogen evolution reaction (HER) on platinum (Pt) electrocatalysts involves the generation of hydrogen atoms and the formation of hydrogen molecules. It is commonly believed that the sites on the surfaces of the terrace (111, 110, and 100) domains are responsible for the formation of hydrogen molecules. However, the electrochemistry of the hydrogen atom generation is not well understood. We created edge-rich platinum electrocatalysts using nano-fabrics comprising entire single-walled carbon nanotubes (SWCNTs) as templates and supports. We then conducted the HER on the edge-rich Pt/SWCNT hybridized electrocatalysts and gained new insights into the electrochemical properties and functions of the edge sites. We propose that the edge sites are oxidized and serve two important functions: they act as atomic barriers, allowing electrons to accumulate within the terrace (111, 110, and 100) domains, and they transfer the electrons to the hydronium ions in the electrical double layer through discharge. Enhancing the discharge capability of the electrocatalysts is an efficient way to reduce the amount of platinum required, and this can be applied to various precious metal-based electrocatalysts to enhance their electrocatalytic activities and durability. [ABSTRACT FROM AUTHOR]

Molecular hydrogen ([H.sub.2]) showed protection against various kinds of oxidative-stress-related diseases. First, it was reported that the mechanism of therapeutic effects of [H.sub.2] was antioxidative effect due to inhibition of the most cytotoxic reactive oxygen species, hydroxy radical (*OH). However, after chronic administration of [H.sub.2] in drinking water, oxidative-stress-induced nerve injury is significantly attenuated even in the absence of [H.sub.2]. It suggests indirect signaling of [H.sub.2] and gastrointestinal tract is involved. Indirect effects of [H.sub.2] could be tested by giving [H.sub.2] water only before nerve injury, as preconditioning. For example, preconditioning of [H.sub.2] for certain a period (~7 days) in Parkinson's disease model mice shows significant neuroprotection. As the mechanism of indirect effect, [H.sub.2] in drinking water induces ghrelin production and release from the stomach via [beta]1-adrenergic receptor stimulation. Released ghrelin circulates in the body, being transported across the blood-brain barrier, activates its receptor, growth-hormone secretagogue receptor. [H.sub.2]-induced upregulation of ghrelin mRNA is also shown in ghrelin-producing cell line, SG-1. These observations help with understanding the chronic effects of [H.sub.2] and raise intriguing preventive and therapeutic options using [H.sub.2]. Key words: molecular hydrogen, preconditioning, Parkinson's disease, ghrelin. L'hydrogene moleculaire ([H.sub.2]) est decrit comme etant protecteur contre divers types de maladies liees au stress oxydatif. Il a d'abord ete rapporte que le mode d'action des effets therapeutiques de l'[H.sub.2] etait un effet antioxydant cause par l'inhibition du radical hydroxyl (*OH), le derive reactif de l'oxygene le plus toxique. Cependant, apres l'administration a long terme d'[H.sub.2] dans l'eau a boire, les lesions nerveuses provoquees parle stress oxydatif sont nettement attenuees, meme en absence d'[H.sub.2]. Cela laisse entendre qu'il existerait une voie de signalisation indirecte de l'[H.sub.2] et que le tractus gastro-intestinal jouerait un role. Les effets indirects de l'[H.sub.2] pourraient etre evalues en donnant de l'eau avec [H.sub.2] seulement, avant les lesions nerveuses, en tant que preconditionnement. Par exemple, le preconditionnement par l'[H.sub.2] pendant une certaine periode (~7 jours) dans un modele murin de maladie de Parkinson permet d'obtenir une neuroprotection notable. Comme mode d'action d'un effet indirect, l'[H.sub.2] dans l'eau a boire engendre la production et la liberation de ghreline par l'estomac par l'intermediaire d'une stimulation des recepteurs [beta]1-adrenergiques. La ghreline liberee circule dans l'organisme, transportee a travers la barriere hemo-encephalique, active son recepteur secretagogue d'hormone de croissance (GHSR). Nous observons aussi la regulation a la hausse de l'ARNm de ghreline engendre par l'[H.sub.2] dans des lignees cellulaires productrices de ghreline (SG- 1). Ces observations contribuent a la comprehension des effets a long terme de l'[H.sub.2] et laissent entrevoir d'interessantes options therapeutiques et de prevention fondees sur l'utilisation de l'[H.sub.2]. [Traduit par la Redaction] Mots-cles : hydrogene moleculaire, preconditionnement, maladie de Parkinson, ghreline., Introduction Inhaling molecular hydrogen ([H.sub.2]) showed protection against brain injury induced by focal ischemia and reperfusion in rat by reducing hydroxy radical (*OH), the most toxic reactive oxygen species (Ohsawa [...]

Background: Colonic motility is regulated by various factors along the gut‐brain axis; however, detailed mechanisms are unknown. This study aimed to examine the involvement of the autonomic nervous system in colonic motility. Suncus murinus (suncus) is a small laboratory mammal suitable for gastrointestinal motility studies. Methods: Colonic motility and concomitant feeding and defecation behaviors in vagotomized and reserpine‐administered suncus were recorded simultaneously for 24 h. Furthermore, we performed immunohistochemistry on tyrosine hydroxylase (TH) and in situ hybridization on corticotropin‐releasing hormone (CRH) in suncus brain. Additionally, we examined c‐Fos expression in the brain using immunohistochemistry in conscious suncus with colorectal distension. Key Results: In vagotomized suncus, clustered giant migrating contractions (GMCs), consisting of strong contractions occurring in a short time, were observed, and the percentage of GMCs without defecation increased. The frequency of GMCs in the reserpine‐administered suncus increased during a light period (ZT0‐4, 4–8) and decreased during a dark period (ZT16‐20, 20–24) compared to a vehicle group. Additionally, the percentage of GMCs without defecation in the reserpine‐administered suncus increased. Suncus TH‐immunopositive neurons were found in the locus coeruleus (LC), as shown in rodents. In contrast, CRH mRNA‐expressing cells were not observed in a region assumed to be the Barrington's nucleus (Bar). Furthermore, colorectal distension in conscious suncus induced c‐Fos expression in LC TH neurons. Conclusions & Inferences: Our results suggest that the vagus and sympathetic nerves are not required for induction of GMCs in vivo. However, they are likely to exert a modulatory role in control of GMC frequency in Suncus murinus. [ABSTRACT FROM AUTHOR]

Composite materials are popular because of their high performance capabilities, but new material development is time-consuming. To accelerate this process, researchers studying material informatics, an academic discipline combining computational science and material science, have developed less time-consuming approaches for predicting possible material combinations. However, these processes remain problematic because some materials are not suited for them. The limitations of specific candidates for new composites may cause potential new material pairs to be overlooked. To solve this problem, we developed a new method to predict possible composite material pairs by considering more materials than previous techniques. We predicted possible material pairs by conducting link predictions of material word co-occurrence networks while assuming that co-occurring material word pairs in scientific papers on composites were reported as composite materials. As a result, we succeeded in predicting the co-occurrence of material words with high specificity. Nodes tended to link to many other words, generating new links in the created co-occurrence material word network; notably, the number of material words co-occurring with graphene increased rapidly. This phenomenon confirmed that graphene is an attractive composite component. We expect our method to contribute to the accelerated development of new composite materials. [ABSTRACT FROM AUTHOR]

Studies have indicated that higher numbers of nurses regarding staffing ensure patient safety and a better practice environment. Using citation analysis, this study visualizes the landscape of nurse staffing research over the last two decades to show the overall publication trends, major contributors, and main research topics. We extracted bibliometric information from PubMed from January 2000 to September 2022. After clustering the network, we analyzed each cluster's characteristics by keyword. A total of 2167 papers were considered for analysis, and 14 clusters were created. The analysis showed that the number of papers published per year has been increasing. Researchers from the US, the UK, Canada, Australia, and Belgium have led this field. As the main clusters in nurse staffing research during the past two decades, the following five research settings were identified: nurse outcome and patient outcome research in acute care hospitals, nurse staffing mandate evaluation research, nursing home research, and school nurse research. The first three clusters accounted for more than 80% of the total number of published papers, and this ratio has not changed in the past 20 years. To further develop nurse staffing research globally, evidence from other geographic areas, such as African and Asian countries, and from long-term care or community settings is necessary. [ABSTRACT FROM AUTHOR]