Niobium–aluminum oxynitride prepared by ammonolysis of oxide precursor obtained through the citrate route

Oxynitrides in the (Nb_1−xAl_x)(O,N) quaternary system were prepared by ammonolysis of oxide precursor obtained through the citrate route. The products at 1000 °C were a mixture of Nb(N,O) and NbN_0.95 at the niobium end (x = 0) and amorphous Al(O,N) at the aluminum end (x = 1). A new cubic compound (A) appeared mixed with Nb(N,O) in the compositional range 0.1 ≤ x ≤ 0.4. Its almost pure product was obtained at x = 0.5. The X-ray diffraction pattern was rock salt type (Nb_0.56Al_0.44)(O_0.38N_0.37□₀₂₅) in F_m−3m with a = 0.43481(1) nm. The product showed superconductivity with T_c = 15 K. Its crystallinity was much improved and its superconducting volume fraction increased to 32% after its thermal annealing at 1100 °C in evacuated sealed tube. A second cubic compound (B), rock salt type Nb[(O,N)_0.85□_0.15] with a = 0.434 nm, was observed mixed with amorphous Al(O,N) in the as-prepared products of the range 0.6 ≤ x ≤ 0.9.     

SBS threshold of a fiber with a Brillouin frequency shiftdistribution

The SBS threshold of a fiber with Brillouin frequency shift distribution along its length is investigated theoretically and experimentally. We obtain a simple equation for estimating the SBS threshold from the effective gain coefficient, which is calculated by using the Brillouin frequency distribution along its length. The dopant concentration dependence of the Brillouin frequency shift are measured for fibers with an F and GeO₂ codoped silica core. The evaluated frequency shift per unit of dopant concentration is 277 MHz/wt% and 45 MHz/wt% for F and GeO₂, respectively, at 1.55 μm. The SBS threshold of a fiber with a nonuniform Brillouin frequency shift distribution prepared by the VAD method is investigated experimentally. The fiber exhibits 7 dB improvement in its SBS threshold. This value is in good agreement with one estimated by calculating the effective gain coefficient. This simple equation will be useful for estimating the SBS threshold of various fibers     

Tyrosine phosphorylation of Crk-associated substrates by focal adhesion kinase. A putative mechanism for the integrin-mediated tyrosine phosphorylation of Crk-associated substrates

Integrin-ligand binding induces the tyrosine phosphorylation of various proteins including focal adhesion kinase (pp125(FAK)) and Crk-associated substrate (Cas). FAK is activated and autophosphorylated by the ligation of integrins, although the substrate of FAK has not been revealed. We show here that p130(Cas) and Cas-L are FAK substrates. FAK directly phosphorylates Cas proteins primarily at the YDYVHL sequence that is conserved among all Cas proteins. Furthermore, the phosphorylated YDYVHL sequence is a binding site for Src family protein-tyrosine kinases, and the recruited Src family kinase phosphorylates the other tyrosine residues within Cas. The Cas-L YDYVHL sequence is phosphorylated upon integrin-ligand binding, and this integrin-mediated tyrosine phosphorylation is inhibited by the cotransfection of the FAK COOH-terminal domain that does not contain a kinase domain. These findings strongly suggest that FAK initiates integrin-mediated tyrosine phosphorylation of Cas proteins; then, Src family tyrosine kinases, which are recruited to phosphorylated Cas and FAK, further phosphorylate Cas proteins.     

Hemolysis test of a centrifugal pump in a pulsatile mode: the effect of pulse rate and RPM variance

Centrifugal pumps are generally employed as nonpulsatile blood flow pumps; however, these pumps can produce pulsatile flow by periodically alternating the impeller rotation speed. This study investigates blood trauma due to the effect of pulse frequency and various ranges of pump speed. The hemolysis tests were conducted using the Gyro C1E3 pump. The study was divided into the following categories: Group 1 in a nonpulsatile mode; Group 2 operated at 40 bpm with 30% of speed variance; Group 3, 60 bpm with 30% of speed variance; Group 4, 40 bpm with 70% of speed variance; and Group 5, 60 bpm with 70% of speed variance. A flow rate of 3 L/min and a total pressure head of 200 mm Hg were employed in all groups to simulate a percutaneous cardiopulmonary support condition. There were no significant differences in the hemolysis levels among Groups 1, 2, and 3. However, Groups 4 and 5 exhibited a significantly higher hemolysis rate compared to the other groups. These results indicate that a high rate of speed variance increases hemolysis; however, a range of less than 30% does not affect hemolysis. The pulse rate has no significant effect on hemolysis. In conclusion, the higher speed variance increases the hemolysis level when a pulsatile mode is applied with a centrifugal pump at the given test conditions. However, a speed variance of less than 30% or a pulse rate of less than 60 bpm does not affect hemolysis.     

Surface modification of zinc oxide nanoparticles by aminopropyltriethoxysilane

Commercial zinc oxide nanoparticles (20–30 nm) were coated by aminopropyltriethoxysilane (APTES) under varying environments. Three different processes, acidic, basic and toluene were used. The effects of coating conditions (acidic, basic and toluene) on the grafting, structural and optical properties of these nanoparticles were studied. In the three cases, it was possible to control the coating and according to X-ray diffraction, BET, TEM and SEM results, it is clear that the APTES coating plays a role of growth inhibitor even at 800 °C. From diffuse reflectance measurements, one can notice that the grafting process did not modify the transmittance spectra of ZnO.     

Change in the mode of gene expression of the hypopharyngeal gland cells with an age-dependent role change of the worker honeybee Apis mellifera L

Major proteins synthesized in the hypopharyngeal gland of the worker honeybee change from bee-milk proteins to alpha-glucosidase in accordance with the age-dependent role change of the worker bee. Previously, we showed that the gene for alpha-glucosidase is expressed specifically in the forager-bee gland [Ohashi, K., Sawata, M., Takeuchi, H., Natori, S. & Kubo, T. (1996) Biochem. Biophys. Res. Commun. 221, 380-385]. Here, we describe the isolation and analysis of cDNAs for two bee-milk 56-kDa and 64-kDa proteins. The 56-kDa protein was a glycoprotein which shared 63.2% and 56.9% amino acid sequence identities with proteins encoded by cDNA for royal-jelly-related protein 57-1 (pRJP57-1) and pRJP57-2. The 64-kDa protein cDNA was identical to pRJP57-1. Thus, these bee-milk proteins seem to form a structurally related protein family. The gene for the 64-kDa protein/RJP57-1 was expressed specifically in the nurse-bee gland, whereas that for the 56-kDa protein was expressed in both the nurse-bee and forager-bee glands. mRNAs for the 56-kDa and 64-kDa proteins were detected by in situ hybridization in a whole acinus of the nurse-bee gland, whereas mRNAs for the 56-kDa protein and alpha-glucosidase were detected in that of the forager-bee gland. Therefore, the individual secretory cells of the acinus of the hypopharyngeal gland were shown to express these genes differently with the age-dependent role change of the worker bee.     

Radiation Tolerance Evaluation of the Ti/Au Bilayer TES Microcalorimeter

We have developed Ti/Au bilayer transition-edge sensor (TES) microcalorimeters for future X-ray astrophysical satellite missions such as DIOS. One possible concern on the space use of TES microcalorimeters is its radiation tolerance. We have evaluated the performance of a Ti/Au bilayer (30/40 nm thick) TES microcalorimeter with 1.5  \(\upmu \) m thick Au absorber, before and after irradiation of 150 MeV proton beam with a total dose of 10 krad, corresponding to 10 years in the low Earth orbit. No significant changes on transition temperature, sensitivity, normal resistance, and critical current were observed. The energy resolution for 5.9 keV X-rays was 5.6  \(\pm \)  0.3 eV (FWHM) after the irradiation, which was slightly worse than 5.1  \(\pm \)  0.3 eV before the irradiation. We consider that our TES has sufficient radiation tolerance in orbit.     

Increased Synovial CD14 mRNA Expression and Proportion of CD14high Subsets in Early-Stage Hip Osteoarthritis: Propensity Matched Score Analysis

The pathophysiology of early-stage hip osteoarthritis (EOA) is not fully understood. Although a previous study in an age-unmatched cohort reported that the number of macrophages was increased in knee EOA compared to late OA (LOA), it remained unclear whether increased macrophages in EOA accurately reflect EOA pathology. We investigated the differences in CD14 expression levels between EOA and LOA using age-unmatched and -matched cohorts. Synovial tissues were obtained from 34 EOA (Tönnis grades 0 and 1) and 80 LOA (Tönnis grades 2 and 3) patients. To correct for differences in demographics between patients with LOA and EOA, we also created propensity score-matched cohorts (16 EOA and 16 LOA). CD14 expression and its association with pain was estimated in LOA and EOA before and after propensity matching. We performed flow cytometry on tissues from the 16 patients, with 8 from each group, to assess for CD14+ subsets in the cells. The CD14 expression in EOA was higher than that in LOA both before and after propensity matching. The proportion of CD14^high subsets in EOA was higher than that in LOA. The CD14 expression was associated with pain in EOA before matching. However, no difference was observed between the pain and CD14 expression after matching in EOA. The increased CD14 expression and the proportion of CD14^high subsets may be important features associated with hip EOA pathology. To accurately compare early and late OA, the analysis of a propensity score-matched cohort is necessary.     

Combined surgery for coronary artery disease and thoracic aortic disease

Combined surgery in 6 cases who had coronary artery disease and thoracic aortic disease simultaneously was analyzed. Case # 1 had ascending aortic replacement under deep hypothermic circulatory arrest because of iatrogenic aortic dissection caused by aortic clamp during the routine coronary artery bypass grafting (CABG). Case # 2 had DeBakey type II chronic dissection. Case # 3 had type I aortic dissection 4 years after the initial CABG. Both case # 2 and # 3 had ascending aortic replacement under retrograde cerebral perfusion along with CABG. Transverse aortic replacement was performed in case # 4, # 5 and # 6 under selective cerebral perfusion along with CABG. Case # 4 was associated with ascending-transverse aortic aneurysm. Case # 5 had aortitis syndrome complicated with severe coronary ostial stenosis and cervical branch stenosis. Case # 6 also had aortitis syndrome, severe coronary ostial stenosis, heavily calcified ascending-transverse aorta, and mitral and aortic regurgitation. This case had mitral and aortic valve replacement additionally. Case # 2 died of low cardiac output syndrome and multi-organ failure postoperatively. Case # 4 did not recover from profound shock that followed the preoperative acute myocardial infarction. The problems of low cardiac output syndrome caused by long interval of ischemic cardiac arrest, and also the problems of proximal anastomotic site of saphenous vein grafts were discussed.