The phase transition from supercooled water to ice is closely related to the electrochemical performance and lifetime of an energy device at sub-zero temperatures. In particular, fuel cells for passenger cars face this issue because they are frequently started and stopped under sub-zero conditions during the winter season. However, there is a lack of visual information regarding the processes that occur within the fuel cell stack, and insight into how to improve the safety and performance during cold starts is lacking.
View Article and Find Full Text PDFIn polymer electrolyte fuel cells (PEFCs), the gas diffusion layer (GDL) is crucial for managing the flooding tolerance, which is the ability to remove the water produced during power generation from the assembled cell. However, an improved understanding of the properties of GDLs is required to develop effective waterproofing strategies. This study investigated the influence of the polytetrafluoroethylene (PTFE) content on the pore diameter, porosity, wettability, water saturation, and flooding tolerance of waterproofed carbon papers as cathode GDLs in PEFCs.
View Article and Find Full Text PDFcan cause infection in ruminants, and its pathogenicity is suggested to be associated with VapN. Despite its wide distribution, no immunological diagnostic method has been developed for VapN-producing . Against this background, we attempted to develop monoclonal antibodies targeting VapN and assess their application in immunostaining.
View Article and Find Full Text PDFThe performance of a polymer electrolyte fuel cell can be enhanced by improving the proton conductivity of the catalyst layer, where the oxygen reduction reaction generates electrochemical power. Protons are conducted through the ionomer coatings on catalyst-supporting carbon particles, which form porous structures that facilitate oxygen diffusion during the reaction within the catalyst layer. Therefore, while a higher ionomer content in the catalyst layer is favorable, the proton conductivity is additionally governed by the type of carbon support.
View Article and Find Full Text PDFAn X-ray computed nano-tomography (nano-CT) system has been established at the BL33XU beamline of SPring-8. The optical system consists of pseudo-Köhler illumination with a sector condenser zone plate, an apodization Fresnel zone plate as the objective lens, and a Zernike phase plate. The imaging detector is a fiber-coupling type X-ray camera.
View Article and Find Full Text PDFBiochim Biophys Acta Biomembr
September 2022
For analysis of the structure of human skin stratum corneum (SC), we introduced low-flux electron diffraction (ED) and developed a new statistical analysis method for obtained ED intensity profiles. By use of this method we compared the differences in the intercellular lipid organization on the SC corneocytes collected at human forehead, cheek, and forearm by the grid-stripping method. As a result, we found a significant regional difference in the distribution of lipid hydrocarbon chain packing domains in the SC; the ring-type ED pattern with orthorhombic symmetry was more often observed in the forearm SC than in the forehead and cheek SCs.
View Article and Find Full Text PDFACS Appl Mater Interfaces
April 2022
Porous media as catalyst supports are key to developing automotive exhaust purification systems. In particular, the water content of these porous media is attracting research attention because catalyst supports containing condensed water vapor at the early stage of cold start require a longer warm-up period. In this regard, water isotherms and evaporation in porous AlO were investigated in this study using in situ small-angle neutron scattering (SANS) experiments.
View Article and Find Full Text PDF[Purpose] This study aimed to examine the effective time allocation for physical therapy activities in patients with stroke. The primary outcome measure was the improvement in the time required to transition from the supine to the sitting position. [Participants and Methods] This study enrolled 19 inpatients with stroke.
View Article and Find Full Text PDFThe purpose of the present study was to investigate molecular compositions of lipid droplets changing in live hepatic cells stimulated with major fatty acids in the human body, i.e., palmitic, stearic, oleic, and linoleic acids.
View Article and Find Full Text PDFStratum corneum (SC), the outermost layer of human skin, acts as an intelligent physicochemical interface between the inside and the outside of our body. To make clear the relationship between structure and physical barrier properties of SC, we developed a method that enables us to simultaneously acquire X-ray diffraction (XD) patterns and transepidermal water loss (TEWL) values using a spread SC sheet isolated from human skin. The synchrotron X-ray was incident on the SC sheet surface at an angle of 45° to avoid interference between the two kinds of measurements.
View Article and Find Full Text PDFThe brain consists of distinct domains defined by sharp borders. So far, the mechanisms of compartmentalization of developing tissues include cell adhesion, cell repulsion, and cortical tension. These mechanisms are tightly related to molecular machineries at the cell membrane.
View Article and Find Full Text PDFWe present herein a method to fabricate a higher-order fiber grating (HOFG) for use as a fiber-cavity mirror in a fiber laser. The HOFG was fabricated by irradiating the Yb-doped large core of a double-clad fiber by a femtosecond pulsed laser. The HOFG served as a laser cavity mirror with a reflectance of 13.
View Article and Find Full Text PDFFactor XIII-A (FXIII-A), which has become known as cellular transglutaminase, plays important roles in mediating cross-linking reactions in various tissues. FXIII-A acts as one of the regeneration molecules in the fish retina and optic nerve after optic nerve injury and becomes activated at the site of injury within a few hours. Previous research has shown that activated FXIII-A induces neurite outgrowth from injured retinal ganglion cells and supports elongation of the regenerating optic nerve.
View Article and Find Full Text PDFWhen axons of the mammalian central nervous system (CNS) are injured, they fail to regenerate, while those of lower vertebrates undergo regeneration after injury. Wingless-type MMTV integration site family (Wnt) proteins play important roles in the CNS, and are reported to be activated after mammalian spinal cord or brain injury. Moreover, for axon growth to proceed, it is thought that small G-proteins, such as CDC42 and Rac1, need to be activated, whereas RhoA must be inactivated.
View Article and Find Full Text PDFWe investigated the effect of dielectric properties of the aqueous medium on the novel type of hydrogel composed of a crude lecithin mixture (PC70) and hexadecanol (HD), in which charged sheet-like bilayers are kept far apart due to interbilayer repulsive interaction. We used dipropylene glycol (DPG) as a modifier of the dielectric properties and examined its effect on the hydrogel by synchrotron X-ray diffraction, differential scanning calorimetry (DSC), polarized optical microscopy, and freeze-fracture electron microscopy. We found that at a DPG weight fraction in the aqueous medium WDPG ≈ 0.
View Article and Find Full Text PDFZebrafish can regenerate several organs such as the tail fin, heart, central nervous system, and photoreceptors. Very recently, a study has demonstrated the photoreceptor regeneration in the alkylating agent N-methyl-N-nitrosourea (MNU)-induced retinal degeneration (RD) zebrafish model, in which whole photoreceptors are lost within a week after MNU treatment and then regenerated within a month. The research has also shown massive proliferation of Müller cells within a week.
View Article and Find Full Text PDFNeuroglobin (Ngb) is a new member of the family of heme proteins and is specifically expressed in neurons of the central and peripheral nervous systems in all vertebrates. In particular, the retina has a 100-fold higher concentration of Ngb than do other nervous tissues. The role of Ngb in the retina is yet to be clarified.
View Article and Find Full Text PDFRetinal degeneration (RD) such as retinitis pigmentosa and age-related macular degeneration are major causes of blindness in adulthood. As one of the model for RD, intraperitoneal injection of N-methyl-N-nitrosourea (MNU) is widely used because of its selective photoreceptor cell death. It has been reported that MNU increases intracellular calcium ions in the retina and induces photoreceptor cell death.
View Article and Find Full Text PDFRetinitis pigmentosa is a disease characterized by the loss of photoreceptor cells. The N-methyl-N-nitrosourea (MNU)-induced retinal degeneration model is widely used to study the mechanism of these retinal degenerative disorders because of its selective photoreceptor cell death. As for the cell death mechanism of MNU, calcium-calpain activation and lipid peroxidation processes are involved in the initiation of this cell death.
View Article and Find Full Text PDFThe surface pressure-area (π-A) isotherms of DMPC, DPPC, and DSPC/cholesterol binary monolayers were systematically measured with great care to gain insight into the lateral molecular packing in these binary monolayer systems. The average molecular area A and the area elastic modulus C(s)⁻¹ at a given surface pressure were calculated as a function of cholesterol mole fraction x(chol). As a result, data reliable enough for the analysis of detailed phase behavior were obtained.
View Article and Find Full Text PDFN-methyl-N-nitrosourea (MNU) is widely used to study the mechanism of retinal degenerative diseases (RDs) because of its selectivity of photoreceptor cell death. Many reports suggest that excessive nitric oxide (NO) plays a crucial role in neuronal cell death. We hypothesized that nitric oxide synthase (NOS)/NO are involved in photoreceptor cell death by MNU.
View Article and Find Full Text PDFFish retinal ganglion cells (RGCs) can regenerate their axons after optic nerve injury, whereas mammalian RGCs normally fail to do so. Interleukin 6 (IL-6)-type cytokines are involved in cell differentiation, proliferation, survival, and axon regrowth; thus, they may play a role in the regeneration of zebrafish RGCs after injury. In this study, we assessed the expression of IL-6-type cytokines and found that one of them, leukemia inhibitory factor (LIF), is upregulated in zebrafish RGCs at 3 days post-injury (dpi).
View Article and Find Full Text PDFBiochim Biophys Acta
December 2014
We examined the volumetric behavior of the dipalmitoylphosphatidylcholine (DPPC)/cholesterol binary bilayer system with high accuracy and more cholesterol concentrations to reveal the detailed molecular states in the liquid-disordered (Ld) phase, the liquid-ordered (Lo) phase and the gel phase. We measured the average specific volume of the binary bilayer at several temperatures by the neutral flotation method and calculated the average volume per molecule to estimate the partial molecular volumes of DPPC and cholesterol in each phase. As a result, we found that the region with intermediate cholesterol concentrations showed a more complicated behavior than expected from simple coexistence of Ld and Lo domains.
View Article and Find Full Text PDFThe sex-determining region Y-box 2 (Sox2) is related not only to pluripotency, but also to cell proliferation. Zebrafish can regain their motor function after spinal cord injury (SCI). Following SCI, new motor neurons are produced from proliferating ependymal cells.
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