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We show how estimates of parameters characterizing inflation-based theories of structure formation localized over the past year when large scale structure (LSS) information from galaxy and cluster surveys was combined with the rapidly developing cosmic microwave background (CMB) data, especially from the recent Boomerang and Maxima balloon experiments. All current CMB data plus a relatively weak prior probability on the Hubble constant, age and LSS points to little mean curvature (Ωtot = 1.08±0.06) and nearly scale invariant initial fluctuations (ns = 1.03±0.08), both predictions of (non-baroque) inflation theory. We emphasize the role that degeneracy among parameters in the Lpk = 212 ± 7 position of the (first acoustic) peak plays in defining the Ωtot range upon marginalization over other variables. Though the CDM density is in the expected range (Ωcdmh2 = 0.17 ± 0.02), the baryon density Ωbh2 = 0.030 ± 0.005 is somewhat above the independent 0.019 ± 0.002 nucleosynthesis estimates. CMB+LSS gives independent evidence for dark energy (ΩΛ = 0.66 ± 0.06) at the same level as from supernova (SN1) observations, with a phenomenological quintessence equation of state limited by SN1+CMB+LSS to wQ < −0.7 cf. the wQ=−1 cosmological constant case.
BOOMERanG has recently resolved structures on the last scattering surface at redshift ˜ 1100 with high signal to noise ratio. We review the technical advances which made this possible, and we focus on the current results for maps and power spectra, with special attention to the determination of the total mass-energy density in the Universe and of other cosmological parameters.
Crop biofortification is increasingly being recognized as a cost-effective and sustainable approach to address the widespread micronutrient malnutrition arising from Fe and Zn deficiencies. Pearl millet as a cereal crop species has higher Fe density than all other major cereals. Earlier studies in pearl millet have shown that breeding lines, hybrid parents, improved populations and composites having high Fe and Zn densities were often based largely or entirely on iniadi pearl millet germplasm. In an attempt to identify additional sources of high Fe density in this group of germplasm, 297 accessions were screened using Perl's Prussian Blue staining, of which 191 accessions (118 from Togo, 62 from Ghana and 11 from Burkina Faso) were re-evaluated during the 2010 rainy and 2012 summer seasons using the inductively coupled plasma atomic emission spectroscopy method. On the basis of the mean performance over the two seasons (environments), large variability was observed for both Fe (51–121 mg/kg) and Zn (46–87 mg/kg) densities. There was a highly significant and positive correlation between the two micronutrients (r= 0.77, P< 0.01). Of these re-evaluated accessions, 49% had higher Fe density than the high-Fe control commercial cultivar ICTP 8203 (81 mg/kg), and most of these accessions also had Zn density ≥ 61 mg/kg (59 mg/kg for ICTP 8203). A total of 27 accessions (20 from Togo and seven from Ghana) having a Fe density of 95–121 mg/kg (1 standard error of difference above that for ICTP 8203) and a Zn density of 59–87 mg/kg were selected as a valuable germplasm resource for genetic improvement of these two micronutrients in pearl millet.
In this study, epidemiological factors of sparganosis cases reported in mainland China from 1959 to December 2012 were analysed. A total of 1061 valid cases were distributed throughout most of the provinces of mainland China, with most cases occurring in Southern and Eastern China. The average age of patients was 29 years (range 0–80 years). Modes of transmission to humans were via contact (54·6%), mainly by application of frog meat as a poultice, foodborne (33·8%), mainly through ingesting frogs or snakes, and waterborne (11·5%) through drinking raw water. The tissue/organs involved were subcutaneous/muscle (43·1%), eyes (31·0%), central nervous system (CNS) (17·9%), urogenital system (3·9%) and visceral organs (3·2%). Obvious differences existed in main risk factors for different areas. Close correlation was found between tissue/organs and risk factors. Main modes of transmission changed during the past decades, from contact (83·8% pre-1979) to foodborne (63·9% post-2000). The tissue/organs involved also changed at the same time. Cases involving eyes fell from 50·0% pre-1979 to 8·3% post-2000, and cases involving CNS increased from 0% pre-1979 to 47·8% post-2000. These results illustrate that China is one of the main epidemic countries of sparganosis in the world. Consumption of frog/snake meat was the main risk factor, although application of frog flesh as a poultice was the main risk factor before 2000. Sparganosis has become one of the neglected but important foodborne/waterborne parasitic diseases in mainland China.
Mg doped ZnO thin films were prepared by DC/RF magnetron co-sputtering in (Ar+O2) ambient conditions using metallic Mg and Zn targets. We present a comprehensive study of the effects of film thickness on the structural, optical and magnetic properties. Room temperature ferromagnetism was observed in the films and the saturation magnetization (MS) increases at first as the film’s thickness increases and then decreases. The MS value as high as ∼15.76 emu/cm3 was achieved for the Mg-doped ZnO film of thickness 120 nm. The optical band gap of the films determined to be in the range 3.42 to 3.52 eV.
Ion bombardment during thin film growth is known to cause structural and
morphological changes in the deposited films and thus affecting the film
properties. These effects can be due to the variation in the bombarding ion
flux or their energy. We have deposited titanium nitride films by two
distinctly different methods, viz. Electron Cyclotron Resonance (ECR) plasma
sputtering and bias assisted reactive magnetron sputtering. The former
represents low energy (typically less than 30 eV) but high density plasma
(1011cm−3), whereas, in the latter case the ion
energy is controlled by varying the bias to the substrate (typically a few
hundred volts) but the ion flux is low (109cm−3). The
deposited titanium nitride films are characterized for their structure,
grain size, surface roughness and electrical resistivity.
We describe a procedure for dispersion bulk Si into a family discretely sized ultrasmall ultrabright nanoparticles. We demonstrate that electrochemically etched, hydrogen capped SinHx clusters with n larger than 20 are obtained within a family of discrete sizes. These sizes are 1.0 (Si29), 1.67 (Si123), 2.15, 2.9, and 3.7 nm diameter. We characterize the particles via direct electron imaging, excitation and emission optical spectroscopy, chromatography, and colloidal crystallization. The band gaps and emission bands are measured. The smallest four are ultrabright blue, green, yellow, and red luminescent particles. The availability of discrete sizes and distinct emission in the red, green and blue range is useful for biomedical tagging, RGB displays, and flash memories.
We report on ‘in-situ’ solution processed homogeneous (200) oriented MgO ~85nm thin films deposited on Si substrates by inkjet printing. These films are found to show ferromagnetic order beyond room temperature with a saturation magnetization MS as high as ~0.63 emu/g. X-ray photoelectron spectroscopy investigations show the absence of any possible contamination effects, while the Mg 2p, and O 1s spectra indicate that the role of defect structure at the Mg site is important in the observed magnetism. By controlling the pH values of the precursors the concentration of the defects can be varied and hence tune the magnetization at room temperature. The origin of magnetism in these MgO thin films appears to arise from the cation vacancies.
The subsolidus phase relations of the Dy-Fe-Al system have been investigated by means of X-ray powder diffraction. There are 5 ternary compounds, 10 binary compounds, and 21 three-phase regions in this system. The solid-solution regions of Dy(Fe1−xAlx)2, DyFe3−xAlx, Dy2(Fe1−xAlx)17, and DyFe12−xAlx have been determined based on the dependence of their unit-cell parameters on the Al content.
Processing of YBa2Cu3O6+x superconducting samples by employing different precursor powder preparation techniques such as ball milling, attrition milling and also narrow particle size distribution powder preparation through coprecipitation by spraying will be discussed. CuO coated with oxalates shows the lowest resistance above T up to room temperature. The extent of corrosion by water has been studied by employing magnetic susceptibility, XPS and X-ray diffraction. Superconducting samples are affected to a considerable extent when treated in water at 60° C and the severity of the attack increases with time.
Polyethylene (PE), polypropylene (PP), polystyrene (PS) and polyethersulfone (PES) were implanted with 200 keV boron ions at three different doses. PS was also implanted with 100 keV boron. A nanoindentation technique and reciprocating sliding wear tests were used to characterize mechanical properties of the implanted polymers. The results showed that hardness increased with increasing dose as well as increasing energy. The percentage increase in hardness was reduced with increasing complexity of the side groups although absolute hardness values were higher. With increasing complexity of the main backbone, polymer chain, the percentage increase in hardness as well as numerical hardness values were lower. These effects were attributed to the relative contributions of cross-linking and chain scission which were viewed as competing processes. Wear tests showed that in general, a lower or intermediate implant dose yielded the best improvement in wear resistance. No specific trends were observed for relating friction coefficient values and improved wear resistance. The results indicate that wear is a complex phenomenon which has a sensitive dependence on hardness and elastic properties of the mating surfaces.
Room temperature Raman scattering spectra are reported for the type II superconductors MxBaySi46 (M-Na, K) which were recently shown to exhibit Tc's ∼ 3.5 K. The spectra are compared to those of other Si46-clathrates which exhibit normal metallic behavior down to 2K. Thirteen of the twenty first-order Raman frequencies predicted by group theory have been detected, and the frequencies are found to be sensitive to the particular dopants. The Raman linewidths observed for the MxBaySi46 system are comparable to those observed for Na8Si46 and K7Si46. The data, taken collectively, suggest that the line broadening in the metallic Si-clathrates is due to important contributions from both the electron-phonon interaction as well as to a random filling of the Si cages.
Studies of the evolution of electrical resistance in an external applied magnetic field, B, as well as with temperature, T, on Cu86Co14 and Cu92Co8 as quenched and annealed melt-spun ribbons, reveal that magnetoresistance, MR, ΔR(B,T)=R(B)-R(0) scales with B/T. Furthermore, it found that annealing up to 600 °C scales the magnetic moment of the Co-rich superparamagnetic nanoparticles such that, the data for the field dependence of the MR obtained at various temperatures collapses onto the same unique and universal curve f(mB/T) with the Langevin variable mB/T governing the overall behaviour.
Optical absorption of nanosized particles in glass was measured. The plasma absorption band was completely spread out for particles below about 1.5 ran in diameter, as also has been found by gold particles in water and a polymer. The growth kinetics suggested growth of spherical particles controlled by diffusion of gold from the matrix to the particles, and a constant number of growing particles, giving a narrow size distribution of particles. For particles below about one ran in diameter (31 gold atoms), the optical absorption was proportional to λ−4, as expected if the absorption results from free electrons in the particles.