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In this paper, for ϕ800mm round billet vertical continuous casting process, a computational study of the effect of Final electromagnetic stirring (F-EMS) at positions (7.5 m, 9 m, 10.5 m and 12 m) from the meniscus of mold on fluid flow and heat transfer has been carried out. Considering the influence of the solidified shell thickness on magnetic field. The thicker the solidified shell, the smaller the magnetic induction intensity and electromagnetic force inside the billet. Once the position is shifted down by 1.5 m, the thickness of the solidified shell increases by about 21 mm and the magnetic induction intensity at the center of the billet decreases by about 6mT. According to the velocity and the 3-D streamline distribution, at the position 7.5 m from the meniscus of mold, the flow velocity is 0.01158 m·s−1 and part of the molten steel has an obvious upward recirculation zone. Moving the position from 9 to 10.5 m, the stirring range and flow velocity are reduced. The flow velocity is 0.00206 m·s−1 at the position 12 m from the meniscus of mold and the molten steel has no effective flow. Electromagnetic stirring accelerates the heat transfer and uniform temperature. It has a great effect on the core temperature, but a little effect on the solidified shell temperature. After adding F-EMS, the core temperature decreased by 2–5 K. As the position moves down from 7.5 to 12 m from the meniscus of mold, the radial length of the action range decreases from 0.13 to 0.03 m. The effective action range of uniform temperature is basically equal to the radial length of liquid fraction fl ≥ 0.7. The industrial experimental results show that adding F-EMS at 9.3 m away from the meniscus of mold can improve the porosity, crack and segregation to a certain extent. [ABSTRACT FROM AUTHOR]

Inkjet printing conductive ink was prepared with the as-prepared silver nanoparticles as conductive fillers and deionized water as the solvent and leveling agent (MY-3000) and silicone defoamer (NXZ) and wetting agent (TRITONX-405) and moisturizer (glycerol) as functional additives. We investigated the effects of viscosity and surface tension of conductive ink and the inkjet print parameters including number of nozzle, print speed, and ink droplet spacing on inkjet printability of conductive ink. The research results show that the inks with the viscosity range of 2.8–9.1 mPa·s and the surface tension of 33.4 mN·m−1 are suitable for inkjet printing. The printing accuracy of the print pattern is related to the number of nozzles and droplet space and the printing layer, but not to the printing speed, but can be changed appropriately to improve the print efficiency. When the mass content of silver nanoparticles is 6.91 wt%, the sheet resistance of the printing pattern with four layers is 2.71 Ω·cm−1, which is in appropriate printing conditions of the inkjet printing voltage of 21 V, printing speed of 60 m· S−1, ink droplet space of 20 μm, and nozzles of 2. The systematic studies of printability and electrical conductivity of inkjet printing silver nanoparticles conductive ink prove the feasibility of the ink and provide some ideas for future applications. [ABSTRACT FROM AUTHOR]

Background: Obstructive sleep apnea (OSA) is associated with cancer incidence and mortality. The underlying mechanism is unclear. This study aims to evaluate the influence of intermittent hypoxia (IH), a novel hallmark of OSA, on tumor and to access the anti-tumor effect of endostatin on a mouse model with OSA. Methods: The C57BL/6 J mice were randomly classified into four groups: control (normoxia) (CTL), control plus endostatin (CTL + ED), IH, and IH plus endostatin (IH + ED). Mice in IH and IH + ED groups were subjected to IH 8 h per day in 5 weeks. Lewis lung cancer cells were injected into the flank of each mouse after 1 week of IH exposure. Endostatin was also intraperitoneally injected after tumor volume reached about 200 mm3. The maximum standard uptake values (SUVmax) were detected by micro-positron emission tomography–computed tomography (micro-PET–CT) imaging prior and post-endostatin administration. Microvessel density (MVD) and vascular endothelial growth factor (VEGF) were determined for evaluating the anti-tumor effect of endostatin among the normoxia and IH conditions. Results: Mice had higher SUVmax in the IH group than the CTL group (p < 0.01). When compared with mice in the CTL group, those in the IH group had significantly greater MVD values (p < 0.001). The SUVmax can be attenuated by endostatin both in the CTL (p < 0.01) and IH conditions (p < 0.001). When compared with CTL group, mice in the IH group had increased MVD values (p < 0.001) and VEGF expression both at mRNA (p < 0.05) and protein levels (p < 0.001 in western blotting results). Treatment with endostatin attenuated serum and tissue VEGF levels, lowering the MVD values. As compared to normoxia condition, the endostatin-therapeutic effects were more significant under the IH condition (p < 0.05 in western blotting results). Conclusions: Micro-PET–CT imaging is a promising non-invasive technique to evaluate the tumor metabolic characteristics under IH condition in vivo. The anti-tumor effect of endostatin under IH condition is superior to that of the normoxia condition. [ABSTRACT FROM AUTHOR]

Mini-channel heat exchangers draw significant attention due to their capability of dissipating high flux heat in a relatively controllable way. The properties of heat transfer and instability of the parallel minichannel heat exchangers were investigated on orbit. The heat exchangers were installed as the evaporators of a two-phaseflow loop in the first Chinese cargo ship (TZ1). R134a was selected as working fluid of the loop. The heat exchangers were designed to be gravitydominated, with the channels' cross section of 1 × 3 mm2, or larger. Small temperature fluctuation was found on the surface of one heat exchanger. It may be caused by the flow-rate fluctuation among the channels; and it could be more likely occur in microgravity. The necking at each entrance of the channels could suppress the fluid fluctuation inside the heat exchanger. For gravity-dominated channels, gravity plays a decisive role in the vapor-liquid distribution in the channels, which in turn affects the heat transfer coefficient of the heat exchanger. [ABSTRACT FROM AUTHOR]

In order to better understand the failure behaviour of brittle or quasi-brittle materials, we developed a numerical model to analyse the creation of a main macro-crack from a large number of micro-cracks. The boundary element method is used to simulate numerically the formation of a main macro-crack by the growth and the coalescence of the micro-cracks. Different two-dimensional panels in PMMA with initial micro-cracks are studied. The macroscopic responses of the panels are observed by simulating the damage process induced by the growth of micro-cracks. The ultimate tensile stress of the material can be then determined. The material toughness heterogeneity is taken into account in the developed model. The toughness heterogeneity is considered as existence of different energy barriers for the growth of micro-cracks. The influences of different parameters such as the level of local stress concentration, the density and the initial length of micro-cracks and the toughness heterogeneity on the failure behaviour of the materials are also studied. The numerical results show that the present model is realistic and efficient. It can be used to describe brittle or quasi-brittle material failure due to the creation of a main macro-crack from micro-cracks. [ABSTRACT FROM AUTHOR]

This study examines the PNA associated atmospheric diabatic heating by linearly isolating the influence of ENSO. The analysis is based on the NCEP–NCAR and ERA-40 reanalyses and a 1,000-year-long integration of the CCCma coupled climate model. Both the vertically integrated and three-dimensional diabatic heating are examined. The Rossby wave sources in association with the PNA are also diagnosed. The PNA-related heating is confined outside the tropics and is dominated by anomalies in the eastern Pacific, with a north–south dipole structure in mid-latitudes and the northern subtropics. The heating anomalies change sign with height in mid-latitudes but have the same sign throughout the troposphere in the northern subtropics. Relatively weak heating anomalies also appear in mid-latitudes, downstream of the heating dipole over North America and the western North Atlantic. The heating anomalies are largely supported by the advections related to the mean state throughout the troposphere, and partially damped by the advections related to the eddy effect, particularly at the upper troposphere over the North Pacific. Broadly similar patterns are seen from the NCEP–NCAR and ERA-40 reanalyses. Yet anomalous heating centers are generally located at relatively lower troposphere for the ERA-40 with respect to the NCEP–NCAR. The tropical heating anomalies are rather weak, remarkably different from those related to ENSO variability. In addition, the Rossby wave source collocates with the atmospheric diabatic forcing in the mid-high latitudes over the PNA sector, and shows no forcing source in the tropics. The results demonstrate possible forcing in the mid-high latitudes, regardless of tropical heating for the PNA teleconnection. The modeled heating and wave forcing anomalies in association with the modeled PNA compare reasonably well with the reanalysis-based estimates, increasing confidence in the observational results. The analysis provides further evidence of the independence of the PNA on ENSO from the diabatic heating point of view. [ABSTRACT FROM AUTHOR]

Cd(OH)2 nanobelts have been synthesized in high yield by a convenient polyol method for the first time. XRD, XPS, FESEM, and TEM were used to characterize the product, which revealed that the product consisted of belt-like crystals about 40 nm in thickness and length up to several hundreds of micrometers. Studies found that the viscosity of the solvent has important influence on the morphology of the final products. The optical absorption spectrum indicates that the Cd(OH)2 nanobelts have a direct band gap of 4.45 eV. [ABSTRACT FROM AUTHOR]

Composites of Sn-Pd particles and multi-walled carbon nanotubes (MWNTs), and of Ni-Co particles and MWNTs were investigated by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The Sn-Pd particle composites were prepared by impregnation deposition, and the Ni-Co particle composites were prepared by electroless deposition on MWNTs synthesized by a chemical vapor deposition method using thermal catalytic decomposition of hydrocarbon. The morphologies and the microstructure of the deposited particles were investigated upon annealing the composites with and without hydrogen. Both the crystalline particle structure and the particle morphology are observed to be different for the samples annealed with and without hydrogen. [ABSTRACT FROM AUTHOR]

The structure, hydrogen storage property, and electrochemical characteristics of the La0.7Mg0.3Ni5.5-x (Al0.5Mo0.5)x (x = 0, 0.2, 0.4, 0.6, 0.8) hydrogen storage alloys have been investigated systematically. It has been found by X-ray powder diffraction and Rietveld analysis that the alloys are multiphase and consist of impurity Ni phase and two main crystallographic phases, namely, the La(La, Mg)2Ni9 phase and the LaNi5 phase, and the lattice parameters and the cell volumes of both the La(La, Mg)2Ni9 phase and the LaNi5 phase increase with increasing Al and Mo content in the alloys. The P-C isotherm curves indicated that the hydrogen storage capacity of the alloy first increases and then decreases with increasing x, and the equilibrium pressure decreases with increasing x. The electrochemical measurements show that the maximum discharge capacity first increases from 298.5 (x = 0) to 328.3 mAh/g (x = 0.6) and then decreases to 304.7 mAh/g (x = 0.8). The high rate dischargeability (HRD) of the alloy electrodes increases lineally from 65.4 pct (x = 0) to 86.6 pct (x = 0.8) at the discharge current density of 1200 mA/g. Moreover, the exchange current density of the alloy electrodes also increases monotonously with increasing x by the linear polarization curves. The hydrogen diffusion coefficient in the alloy bulk, D, increases with increasing Al and Mo content and thus enhances the low-temperature dischargeability (LTD) of the alloy electrodes. [ABSTRACT FROM AUTHOR]

In view of the possible crosstalks between hematopoiesis and neuropoiesis, we evaluated two microenvironments, murine neonatal neural cell line C17.2 and primary embryonic aorta-gonad-mesonephros (AGM) stromal cells, on the ex vivo expansion of CD34+ cells from human cord blood. In a contact culture system, C17.2 or AGM cells significantly enhanced the expansion of CD34+ cells to a panel of early and committed hematopoietic progenitor cells. In a noncontact transwell system, pre-established C17.2 cells significantly increased the expansion of total nucleated cells, CD34+ cells and multilineage colony forming cells (P<0.01). Expanded cells were infused into nonobese diabetic/severe-combined immunodeficient mice. The engraftment of human (hu)CD45+ cells in the bone marrow of these mice was consistently higher in all the 10 experiments conducted with the support of C17.2 cells when compared with those in respective control groups (11.9 vs 2.43%, P=0.03). Using RT-PCR and Southern blot analysis, we showed that AGM and C17.2 cells expressed a panel of hematopoietic, bone morphogenetic and neurotrophic factors. Our data provided the first evidence on the promoting effects of a neural progenitor cell line on hematopoiesis at a noncontact condition. The mechanism could be mediated by the expression of multilineage regulatory factors.Leukemia (2005) 19, 91-97. doi:10.1038/sj.leu.2403542 Published online 21 October 2004 [ABSTRACT FROM AUTHOR]

Fine titanate nanowires of K[sub 2]Ti[sub 8]O[sub 17] structure with a diameter of 5–10 nm and a typical length of several micrometers to several tens of micrometers have been synthesized hydrothermally via a reaction of titania particles and KOH solution. The growth of nanowires is along the [010] direction. The surface area of nanowires can exceed more than 300 m[sup 2]/g, which is expected to be significant in their applications to catalysis and other fields. Calcination over 600 °C causes K[sub 2]Ti[sub 8]O[sub 17] nanowires to decompose to K[sub 2]Ti[sub 6]O[sub 13] and TiO[sub 2]. [ABSTRACT FROM AUTHOR]

Presents a study that examined cobblestone area-forming cells, long term culture-initiating cells and mouse repopulating cells in neonatal blood (NB). Review of related literature; Background on human hematopoiesis; Analysis of cryopresevation and thawing of neonatal blood and umbilical cord blood; Implications for the use of NB as a source of hematopoietic pluripotent stem cells.

Infusion of ex vivo expanded megakaryocytic (MK) progenitor cells is a strategy for shortening the duration of thrombocytopenia after haematopoietic stem cell transplantation. The cell dose after expansion has emerged as a critical factor for achieving the desired clinical outcomes. This study aimed to establish efficient conditions for the expansion of the MK lineage from enriched CD34+ cells of umbilical cord blood and to investigate the effect of platelet-derived growth factor (PDGF) in this system. Our results demonstrated that thrombopoietin (TPO) alone produced a high proportion of CD61+CD41+ cells but a low total cell count and high cell death, resulting in an inferior expansion. The addition of interleukin-1β (IL-1β), Flt-3 ligand (Flt-3L) and to a lesser extent IL-3 improved the expansion outcome. The treatment groups with three to five cytokines produced efficient expansions of CFU-MK up to 400-fold with the highest yield observed in the presence of TPO, IL-1β, IL-3, IL-6 and Flt-3L. CD34+ cells were expanded by five to 22-fold. PDGF improved the expansion of all cell types with CD61+CD41+ cells, CFU-MK and CD34+ cells increased by 101%, 134% and 70%, respectively. On day 14, the CD61+ population consisted of diploid (86.5%), tetraploid (11.8%) and polyploid (8N–32N; 1.69%) cells. Their levels were not affected by PDGF. TPO, IL-1β, IL-3, IL-6, Flt-3L and PDGF represented an effective cytokine combination for expanding MK progenitors while maintaining a moderate increase of CD34+ cells. This study showed, for the first time, that PDGF enhanced the ex vivo expansion of the MK lineage, without promoting their in vitro maturation. PDGF might be a suitable growth factor to improve the ex vivo expansion of MK progenitors for clinical applications. Bone Marrow Transplantation (2001) 27, 1075–1080. [ABSTRACT FROM AUTHOR]

For preparing a berberine-sensitive electrode, 5,10,15,20-tetrakis[2-(2,3,4,6-tetraacetyl-β-D-glucopyranosyl)-1-O-phenyl]porphyrin (T( o-glu)PPH2) was synthesized from the reaction of pyrrole with ortho-acetylglycosylated benzaldehyde by Lindsay’s method. The electrode based on T( o-glu)PPH2 with an optimized membrane composition exhibits Nernstian response to berberine in the concentration range 2.4 × 10–7–5.0 × 10–3 mol L–1, with a pH range from 3.9 to 10.2, and a fast response time of 30 s. The electrode shows fair selectivity towards berberine with respect to common co-existing species. T( o-glu)PPH2 shows better potentiometric response characteristics comparing to chloro[5,10,15,20-tetrakis[2-(2,3,4,6-tetraacetyl-β-D-glucopyranosyl)-1-O-phenyl]-porphinato]-manganese (MnT( o-glu)PPCl) and better selectivity towards berberine than tetraphenylporphyrin (TPPH2). The effect of the composition of the electrode membrane has been studied and the experimental conditions optimized. The contents of berberine in pharmaceutical tablets were determined by direct potentiometry and the results agreed with values obtained by the pharmacopoeia method. [ABSTRACT FROM AUTHOR]

Reports on a study which found that the promoter region of the 5-HT2C receptor gene, located on the X chromosome, exhibits four polymorphisms that can alter expression levels of the 5-HT2C receptor and contribute to pathophysiological differences. Genotype and haplotype frequencies of polymorphisms; Tardive dyskinesia in patients with schizophrenia.

Lattice-matched In0.49Ga0.51P/GaAs superlattices were grown on (001) GaAs substrates using metalorganic chemical vapor deposition. The interface properties were characterized by photoluminescence, transmission electron microscopy, and x-ray diffraction. By varying the growth temperature, the precursor flow rates, and the growth interruption at the interfaces, we found that, while arsenic and phosphorus carry over have some effect on the formation of a low-bandgap InGaAsP quaternary layer at the interfaces, the In surface segregation seems to play an important role in the formation of the interface quaternary layer. Evidence of this indium segregation comes from x-ray and photoluminescence studies of samples grown at different temperatures. These studies show that the formation of an interfacial layer is more prominent when the growth temperature is higher. Growing a thin (∼1 monolayer thick) GaP intentional interfacial layer on top of the InGaP before the growth of the GaAs layer at the P→As transition effectively suppresses the formation of the low-bandgap unintentional interface layer. On the other hand, the growth of a thin GaAsP (or GaP) layer before the growth of the InGaP layer, at the As→P transition increases the formation of a low-bandgap interfacial layer. This nonequivalent effect of a GaP layer at the two interfaces on the PL properties is discussed. [ABSTRACT FROM AUTHOR]

Multiple-stacked InP self-assembled quantum dots (SAQD or QD) were grown on an In0.5Al0.3Ga0.2P matrix lattice-matched on a GaAs (001) substrate using metalorganic chemical vapor deposition. Cathodoluminescence (CL) scanning electron microscopy, and transmission electron microscopy were employed to characterize the optical, morphological, and structural properties of the grown QDs. We found that the CL line width broadens and the surface becomes rough with an increase in the number of stacked QD layers in the structure. However, by introducing thin tensile-strained Al0.6Ga0.4P layers in the middle of In0.5Al0.3Ga0.2P spacer layers to compensate the compressive strain of the InP QD layers, the CL and morphology are significantly improved. Using this technique, 30-stacked InP/In0.5Al0.3Ga0.2P QD structures with improved CL properties and surface morphology were realized. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor about leukemia.