► Actuator using hydrogen storage alloy (HSA) shows a reversible bending motion. ► Pd sputtering on the HSA surface remarkably improves the bending characteristics. ► Optimal thickness of Cu plating ...on HSA 20μm thick is around 10μm. ► Critical aspect ratio of actuator free of constraint by width deformation is five. ► Bending behavior can be controlled by adjusting hydrogen pressure.
Bending behavior of a miniature actuator utilizing Pd–Ni hydrogen storage alloy (HSA) has been investigated on hydriding and dehydriding process. The actuator has a bimorph structure consisting of the HSA thin sheet and copper plating on one side of the sheet. Palladium sputtering on the back surface of the HSA significantly improves bending characteristics due to the catalytic action of palladium. The maximum bending velocity is obtained in the HSA with 10μm thick Cu-plating. The bending actuators having the same aspect ratio (length to width) and different dimensions show the same bending velocity and the critical aspect ratio of the actuator free from the constraint by deformation in width direction is around five. The bending behavior can be controlled by adjusting the surrounding hydrogen pressure.
We used a model of chronic unloading followed by reloading to examine the apoptotic responses associated with soleus muscle atrophy and subsequent recovery. Male Wistar rats were subjected to ...hindlimb unloading (HU) for 2 weeks and subsequent reloading for 0, 3, 7 and 14 days. One-half of the HU-reloaded rats were administered cyclosporine A (CsA), a calcineurin (CaN) inhibitor. There was fibre atrophy (73%) and a decrease in slow type I fibre/myosin heavy chain (MyHC) composition in the soleus muscle after 2 weeks of HU. Fibre size and type I MyHC composition recovered to near the age-matched control levels by recovery day 14 in non-treated, but not in CsA-treated, rats. Myonuclear number was lower and the number of apoptotic nuclei higher in 2-week HU than control rats. These values returned to control levels after 7 and 14 days of recovery, respectively, in both HU-recovery groups. After 2 weeks of HU, the levels of heat shock proteins (Hsp) 60 and 72, mitochondrial cytochrome c oxidase subunit IV (Cox IV), and peroxisome proliferator-activated receptor gamma coactivator 1 (PGC-1) proteins were lower than control. The levels of all of these proteins gradually increased to or above the control levels during cage recovery in both groups. Our results indicate that apoptotic mechanisms are involved in the modulation of myonuclear number during chronic unloading and subsequent reloading. Furthermore, it appears that CaN is related to fibre size and phenotype adaptations, but not to apoptotic responses.
Acute GVHD (aGVHD) is a major obstacle to allogeneic hematopoietic SCT (alloHSCT). Although it is thought that aGVHD is initiated in secondary lymphoid organs at a very early stage of alloHSCT, ...whether CD4(+)FOXP3(+) regulatory T-cells (Tregs) have an impact on aGVHD development during this period remains unclear. Here, we measured Tregs in peripheral blood as early as possible after HLA-mismatched alloHSCT, and assessed the incidence of aGVHD. Flow cytometric analyses revealed that at the second week after HSCT, patients with aGVHD had significantly (P=0.018) lower Treg:CD4(+)T-cell ratios than those without aGVHD. As these differences were seen before the development of aGVHD, these ratios can predict the incidence of aGVHD. The cumulative incidence of aGVHD in patients with ratios of <9% was significantly higher than that in patients with ratios of 9% (P=0.0082, log-rank test). Additionally, the specific ratio of Tregs:CD4(+)T-cells was the most significant value among all other possible lymphocyte-associated ratios and absolute cell counts. These findings suggest that the ratio of Tregs:CD4(+)T-cells at the second week post HLA-mismatched alloHSCT might be a potent predictor of aGVHD in these patients. The practical efficacy of this finding should be verified in further interventional studies.
Extramedullary (EM) relapse of leukemia after allo-SCT in patients with AML/myelodysplastic syndrome has been increasingly reported. The reduced effectiveness of the GVL effect in EM sites, as ...compared with BM, has been suggested to underlie this problem. We retrospectively analyzed the pattern of relapse after haploidentical SCT (haplo-SCT), performed as the first or second SCT. Among 38 patients who received haplo-SCT as their first SCT, the cumulative incidences of BM and EM relapse at 3 years were 40.5 and 10.9%, respectively. Among 19 patients who received haplo-SCT as their second SCT, the cumulative incidences of BM and EM relapse were 30.9 and 31.9%, respectively. Moreover, most of the patients who underwent repeat haplo-SCT for the treatment of EM relapse had further EM relapse at other sites. Post-relapse survival did not differ significantly with different patterns of relapse. The frequent occurrence of EM relapse after haplo-SCT, particularly when performed as a second SCT, suggests that the potent GVL effect elicited by an HLA disparity also occurs preferentially in BM. Our findings emphasize the need for a treatment strategy for EM relapse that recognizes the reduced susceptibility of EM relapse to the GVL effect.
Vertically aligned α-Fe2O3 nanorod arrays were synthesized by a quasi-topotactic transition of solvothermal derived β-FeOOH nanowire-like arrays on a fluorine-doped tin oxide (FTO) coated glass ...substrates. Co-existence of chloride ions and acetonitrile in the precursor solutions was found to be essential for synthesizing 211-oriented β-FeOOH nanowire-like arrays. Field-emission scanning electron microscopy (FE-SEM) observation revealed that heterogeneous nucleation of β-FeOOH preferentially occurs on ridges of the FTO crystal than flat surfaces. High-resolution transmission electron microscopy (HR-TEM) and selected-area electron diffraction (SAED) studies revealed that the 110-oriented α-Fe2O3 nanorod arrays were successfully formed. 110-oriented α-Fe2O3 nanorod arrays prepared by this method exhibit pronounced photocurrent response under visible light illumination. Photo-electrochemical properties of α-Fe2O3 nanorod arrays were discussed from the viewpoint of its electronic and crystal structures.
•Hematite nanorod arrays have been synthesized by a quasi-topotactic transition.•Direct evidence of quasi-topotactic transition was confirmed by HR-TEM and SAED.•110-oriented hematite nanorod arrays showed photoelectrochemical water oxidation.
PDF
