Synthesis and characterization of self-assembled nanofiber-bundles of V2O5: their electrochemical and field emission properties

High-quality self-assembled V(2)O(5) nanofiber-bundles (NBs) are synthesized by a simple and direct hydrothermal method using a vanadium(v) hydroxylamido complex as a vanadium source in the presence of HNO(3). The possible reaction pathway for the formation of V(2)O(5) NBs is discussed and demonstrated that HNO(3) functions both as an oxidizing and as an acidification agent. V(2)O(5) NBs are single-crystals of an orthorhombic phase that have grown along the [010] direction. A bundle is made of indefinite numbers of homogeneous V(2)O(5) nanofibers where nanofibers have lengths up to several micrometres and widths ranging between 20 and 50 nm. As-prepared V(2)O(5) NBs display a high electrochemical performance in a non-aqueous electrolyte as a cathode material for lithium ion batteries. Field emission properties are also investigated which shows that a low turn-on field of ～1.84 V μm(-1) is required to draw the emission current density of 10 μA cm(-2).     

A self-agency bias in preschoolers' causal inferences.

Preschoolers' causal learning from intentional actions—causal interventions—is subject to a self-agency bias. The authors propose that this bias is evidence-based, in other words, that it is responsive to causal uncertainty. In the current studies, two causes (one child controlled, one experimenter controlled) were associated with one or two effects, first independently, then simultaneously. When initial independent effects were probabilistic, and thus subsequent simultaneous actions were causally ambiguous, children showed a self-agency bias. Children showed no bias when initial effects were deterministic. Further controls established that children's self-agency bias is not a wholesale preference but rather is influenced by uncertainty in causal evidence. These results demonstrate that children's own experience of action influences their causal learning, and the findings suggest possible benefits in uncertain and ambiguous everyday learning contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Depression among Latinos in the United States: A meta-analytic review.

The authors conducted a meta-analytic review to assess the prevalence of major depressive disorder and depressive symptoms among Latinos compared with non-Latino Whites in the United States using community-based data. Random-effects estimates were calculated for 8 studies meeting inclusion criteria that reported lifetime prevalence of major depressive disorder (combined N = 76,270) and for 23 studies meeting inclusion criteria that reported current prevalence of depressive symptoms (combined N = 38,997). Findings did not indicate a group difference in lifetime prevalence of major depressive disorder (odds ratio = 0.89, 95% confidence interval = 0.72, 1.10). Latinos reported more depressive symptoms than non-Latino Whites (standardized mean difference = 0.19, 95% confidence interval = 0.12, 0.25); however, this effect was small and does not appear to suggest a clinically meaningful preponderance of depressive symptoms among Latinos. Findings are examined in the context of theories on vulnerability and resilience, and recommendations for future research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Blockage of KHSRP-NLRP3 by MCC950 Can Reverse the Effect of Manganese-Induced Neuroinflammation in N2a Cells and Rat Brain

Manganese neurotoxicity has been reported to cause a neurodegenerative disease known as parkinsonism. Previous reports have shown that the expression of the KH-type splicing regulatory protein (KHSRP), a nucleic acid-binding protein, and NLRP3 is increased upon Mn exposure. However, the relation between these two during Mn toxicity has not been fully deduced. The mouse neuroblastoma (N2a) and SD rats are treated with LPS and MnCl₂ to evaluate the expression of KHSRP and NLRP3. Further, the effect of the NLRP3 inhibitor MCC950 is checked on the expression of NLRP3, KHSRP and pro-inflammatory markers (TNFα, IL-18 and IL-1β) as well as the caspase-1 enzyme. Our results demonstrated an increment in NLRP3 and KHSRP expression post-MnCl₂ exposure in N2a cells and rat brain, while on the other hand with LPS exposure only NLRP3 expression levels were elevated and KHSRP was found to be unaffected. An increased expression of KHSRP, NLRP3, pro-inflammatory markers and the caspase-1 enzyme was observed to be inhibited with MCC950 treatment in MnCl₂-exposed cells and rats. Manganese exposure induces NLRP3 and KHSRP expression to induce neuroinflammation, suggesting a correlation between both which functions in toxicity-related pathways. Furthermore, MCC950 treatment reversed the role of KHSRP from anti-inflammatory to pro-inflammatory.     

Direct Electricity Production from Nematostella and Arthemia’s Eggs in a Bio-Electrochemical Cell

In recent years, extensive efforts have been made to develop clean energy technologies to replace fossil fuels to assist the struggle against climate change. One approach is to exploit the ability of bacteria and photosynthetic organisms to conduct external electron transport for electricity production in bio-electrochemical cells. In this work, we first show that the sea anemones Nematostella vectensis and eggs of Artemia (brine shrimp) secrete redox-active molecules that can reduce the electron acceptor Cytochrome C. We applied 2D fluorescence spectroscopy and identified NADH or NADPH as secreted species. Finally, we broaden the scope of living organisms that can be integrated with a bio-electrochemical cell to the sea anemones group, showing for the first time that Nematostella and eggs of Artemia can produce electrical current when integrated into a bio-electrochemical cell.     

Studies of unsaponifiables in several vegetable oils

The unsaponifiable fractions of soybean, cottonseed, coconut, olive, and avocado oils have been studied in detail. The oils differed in the contents of total unsaponifiables, squalene, tocopherols, and sterols and also in the composition of the tocopherol and sterol fractions. The presence of absence of individual unsaponifiable components may help in establishing the identity of each of the investigated oils and in detecting of admixture by another oil.     

Synthesis of platinum single-crystal nanoparticles in water vapor

Platinum (Pt) nanoparticles have broad application in automobile pollution control, sensors, and fuel cells. Single-crystal platinum particles over the range of nano- to micron-meters were synthesized at the Pt/SiC interface in high pressure water vapor at 1200 °C. These particles exhibited a cube–octahedral shape with predominant (111) facets. Formation of the Pt particles is likely due to water vapor-facilitated oxidation of the platinum silicide, resulting from the interaction between SiC and Pt. Well-aligned Pt single-crystal particles with sizes of tens to hundreds nanometers were obtained on the surface of arc-melted Pt₂Si after exposure in flowing water vapor (90 cm/min) at 1200 °C for 5 min. The potential applications of this finding are discussed.     

Microstructure and mechanical properties of two-phase Fe30Ni20Mn20Al30. Part I: Microstructure

The microstructure of Fe₃₀Ni₂₀Mn₂₀Al₃₀ in both the as-cast condition and after annealing at 823 K for various times up to 72 h was characterized using transmission electron microscopy, scanning transmission electron microscopy, synchrotron-based X-ray diffraction, and atom probe tomography. The microstructure exhibited a basketweave morphology of (Mn, Fe)-rich B2-ordered (ordered b.c.c.) and (Ni, Al)-rich L2₁-ordered (Heusler type) phases with a lattice misfit of only 0.85 % and interfaces aligned along 〈100〉. The phase width increased from 5 nm for the as-cast alloy to 25 nm for 72 h annealed material, with no change in the elemental partitioning between the phases, with a time exponent for the coarsening kinetics of 0.19. Surprisingly, it was found that the room temperature hardness was largely independent of the phase width.