Differences in Si doping efficiency in tertiarybutylarsine,monoethylarsine and arsine for GaAs and AlGaAs grown by MOVPE

We investigate differences in Si doping of GaAs and AIGaAs between group-V sources. Si₂H₆ and SiH₄ doping dependence on growth temperature, V/III ratio, total flow rate, growth rate, and off angle of substrate orientation was examined using tertiarybu-tylarsine (TBAs), monoethylarsine (EtAs), and arsine with a horizontal atmospheric pressure reactor. With either dopant source, Si incorporation for films grown using TBAs or EtAs was always higher than that using arsine. Using silane, dependence of Si incorporation on growth temperature and total gas flow velocity is different between group-V sources. Using disilane, dependence on V/III ratio and total gas flow velocity is different between group-V sources. These results imply that gas phase reactions play an important role. From the kinetic simulation of the decomposition of group-V sources, we verified that the concentrations of AsH₃, AsH₂, and AsH in vapor near the substrate are quite different among group-V sources. AsH₂ is dominant reactant when using TBAs. We propose that H₂AsSiH₃ (silylarsine) is formed by the reaction between AsH₂ radical and SiH₄ and silylarsine should contribute Si incorporation reactions, resulting in high Si incorporation efficiency with TBAs and EtAs. We also suggest that AsH₃ inhibits Si incorporation.     

Homozygous beta(+)-thalassemia due to -31 A to G mutation

The cells of Martinotti are unique neurons of the cerebral cortex with ascending axons. Giovanni Martinotti (1857-1928), professor of anatomic pathology at the University of Bologna, has been claimed to be the discoverer of such cells. Nevertheless, no papers specifically concerning neuroanatomy have been found in his curriculum. The authors have been able to establish that Carlo Martinotti (1859-1918), a pupil of Camillo Golgi (1843-1926) was the legitimate discoverer of the nerve cells carrying his own name.     

TDEG in In0.53Ga0.47As-InP heterojunction grown by chloride VPE

We report the first successful growth of selectively doped In0.53Ga0.47As-InP hcterojunctions by the chloride vapour phase epitaxy, and the observation of TDEG with a maximum electron mobility of 106 000 cm2 V?1 s?1 at 4.2 K.     

1,6-α-L-Fucosidases from Bifidobacterium longum subsp. infantis ATCC 15697 Involved in the Degradation of Core-fucosylated N -Glycan

Bifidobacterium longum subsp. infantis ATCC 15697 possesses five α-L-fucosidases, which have been previously characterized toward fucosylated human milk oligosaccharides containing α1,2/3/4-linked fucose [Sela et al.: Appl. Environ. Microbiol., 78, 795-803 (2012)]. In this study, two glycoside hydrolase family 29 α-L-fucosidases out of five (Blon_0426 and Blon_0248) were found to be 1,6-α-L-fucosidases acting on core α1,6-fucose on the N-glycan of glycoproteins. These enzymes readily hydrolyzed p-nitrophenyl-α-L-fucoside and Fucα1-6GlcNAc, but hardly hydrolyzed Fucα1-6(GlcNAcβ1-4)GlcNAc, suggesting that they de-fucosylate Fucα1-6GlcNAcβ1-Asn-peptides/proteins generated by the action of endo-β- N-acetylglucosaminidase. We demonstrated that Blon_0426 can de-fucosylate Fucα1-6GlcNAc-IgG prepared from Rituximab using Endo-CoM from Cordyceps militaris. To generate homogenous non-fucosylated N-glycan-containing IgG with high antibody-dependent cellular cytotoxicity (ADCC) activity, the resulting GlcNAc-IgG has a potential to be a good acceptor substrate for the glycosynthase mutant of Endo-M from Mucor hiemalis. Collectively, our results strongly suggest that Blon_0426 and Blon_0248 are useful for glycoprotein glycan remodeling.     

Effect of asphyxia on the composition of cationic elements in the perilymph

To elucidate the role of free radicals in the cochlea, cationic elements in the perilymph of the scala tympani in normal and asphyxic guinea pigs were measured by an inductively coupled plasma atomic emission spectrometer. The concentrations of 7 cationic elements (i.e., calcium, copper, iron, magnesium, phosphorus, lead and zinc) were measured simultaneously in a sample of the perilymph taken before, during and after asphyxia. There was no significant change in these cationic elements during asphyxia for 3 min. In contrast to the stationary level during asphyxia, the iron concentration was significantly elevated at 5 min after re-ventilation following asphyxia and decreased rapidly toward the pre-asphyxic level thereafter, although no significant change was observed in other cationic elements. These results were comparable to the theory of non-protein-bound iron accumulation produced by an O2-dependent mechanism during re-perfusion.     

Tomographic imaging of counter-current bubbly flow by wire mesh tomography

The objective of this work is to investigate characteristics of counter-current bubbly flow in a circular pipe with an inner diameter of 50 mm by using wire mesh tomography (WMT). The accuracy of WMT on void fraction measurement is also clarified by comparing the result with a non-intrusive optical method. The accuracy is within ±10%. Local void fractions of many flow conditions are reported. Local void fraction profile affected by superficial liquid velocity and bubble size is shown and discussed. Furthermore, intrusive effects, including bubble break-up and bubble deceleration, are also investigated. Bubbles passing a transparent wire mesh sensor (WMS) are investigated by the optical method. It is shown that bubbles are broken and decelerated by wires of the sensor. It can be concluded that the bubble break-up rate increase with increasing of bubble velocity. However, the bubble deceleration is not depending on the bubble velocity.     

Self-radiation damage in plutonium and uranium mixed dioxide

In plutonium compounds, the lattice parameter increases due to self-radiation damage by α-decay of plutonium isotopes. The lattice parameter change and its thermal recovery in plutonium and uranium mixed dioxide (MOX) were studied. The lattice parameter for samples of MOX powders and pellets that had been left in the air for up to 32 years was measured. The lattice parameter increased and was saturated at about 0.29%. The change in lattice parameter was formulated as a function of self-radiation dose. Three stages in the thermal recovery of the damage were observed in temperature ranges of below 673 K, 673-1073 K and above 1073 K. The activation energies in each recovery stage were estimated to be 0.12, 0.73 and 1.2 eV, respectively, and the corresponding mechanism for each stage was considered to be the recovery of the anion Frenkel defect, the cation Frenkel defect and a defect connected with helium, respectively.     

Immature megakaryocytes undergo apoptosis in the absence of thrombopoietin

OBJECTIVES: We prospectively performed a two-step risk assessment in patients in the early phase after acute myocardial infarction (MI). BACKGROUND: Noninvasive methods like Holter electrocardiographic monitoring (HM) and determination of the left ventricular ejection fraction (EF) as well as the invasive technique of programmed ventricular stimulation (PVS) have been used to identify patients in the late phase after MI as candidates for prophylactic implantation of a cardioverter/defibrillator. However, it is unclear whether these results can be transferred to patients following acute MI. METHODS: A series of 657 patients with acute MI (< or = 75 years) underwent HM and EF. If one of the two methods yielded abnormal findings (HM > or = 20 ventricular ectopic beats/h/> or =10 ventricular pairs/day/ventricular tachycardia; EF < or = 40%), PVS was done (abnormal PVS: induction of monomorphic ventricular tachycardia, duration >10 s, cycle length > or = 230 ms). RESULTS: Of 657 patients, 304 (46%) had either an abnormal HM or EF. The PVS performed in 146 of 304 patients was abnormal in 22. During a mean follow-up of 37 months, there were 106 (16%) deaths, being sudden in 24 (3.6%), nonsudden cardiac in 45 (6.8%). The incidence of arrhythmic events (sudden cardiac death, symptomatic ventricular tachycardia, cardiac arrest) was 18% (4/22) with an abnormal PVS and only 4% (5/124) with a normal PVS (odds ratio 4.0, p=0.032). CONCLUSIONS: The rate of arrhythmic events is low in post-MI patients in the 1990s. Nevertheless, a two-step risk stratification is helpful in selecting candidates for a defibrillator trial aiming at primary prevention of sudden cardiac death after MI.     

Anaplastic large-cell lymphoma of null-cell type with multiple bone involvement

The knowledge on the functional structure of the spleen is gained from the analysis of diseases, and immunological studies. Significant information is gained from model tests and isolated cells. The latter is advantageous in coincidence with the studies of intercellular relations. The main function of the spleen resides in "purification" of the blood. The vascular system, white pulp, red pulp and the marginal zone participate in this process. T-dependent zones of the white pulp are restricted by the circumference reticulum (CR) of periarterial lymphatic sheaths. CR is a morphologic substrate of retro-directional flow of lymphocytes. In addition to T lymphocytes and a certain amount of B lymphocytes, the T-dependent zones contain interdigitizing cells. The B-dependent zones, in addition to lymphocytes, contain dendrite reticular cells. The cords are constituted by varied cellular and extracellular compartments, especially macrophages, fibroblastic reticular cells and various fibrous components. The latest filtration barrier is formed by the wall of sinuses of the red pulp. The achievement of new functional knowledge resides prospectively in the use of lectins, anti-collagen antibodies, fibronectins, proteoglycanes and other various molecules participating in intercellular relations, or morphometric studies, they can provide information on the newest subpopulations of cells in both red and white pulp, that are so far inaccurately defined.     

Selectively doped n+ InP/n? GaInAs heterostructure prepared using chloride transport vapour-phase epitaxy

A field-effect transistor with a 2 ?m Au gate was fabricated on a selectively doped InP/GaInAs heterostructure grown using chloride transport vapour-phase epitaxy. Complete pinch-off was observed, and transconductance of 90 and 160 mS/mm were measured at 295 and 77 K, respectively. From analysis of the drain I/V characteristic, two-dimensional electron gas at the interface was revealed to be the dominant factor for the channel current. This is the first report of a successful preparation of an n+ InP/n? GaInAs heterostructure for the selectively doped field-effect transistor.