Soft chemical synthesis of new layered and three-dimensional oxide hydrates, hxVxW1-xO3×yH2O, related to WO3×2 H2O and WO3. times.1/3 H2O

Two new vanadium-tungsten oxide hydrates of the formulas, H0.125V0.125W0.875O3.1.5H2O (I) and Ho.33V0.33W0.67O3.1/3H2O (II), have been synthesized by acid-leaching of LiVWO6 with aqueous HNO3/HCl. While phase I obtained by treatment of LiVWO6 with dilute HNO3/HCl possesses an orthorhombic structure (a = 7.77(3), b = 13.87(6), c = 7.44(3) angstrom) related to WO3.2H2O, phase II, prepared by refluxing LiVWO6 with concentrated HNO3, is isostructural with WO3.1/3H2O. Dehydration of II around 330-degrees-C yields a hexagonal phase (III, a = 7.25(4), c = 7.74(3) angstrom) isotypic with hexagonal WO3. Both land III exhibit redox and acid-base intercalation reactivity characteristic of layered and tunnel structures.

Soft-chemical synthesis of new non-linear optical materials, K0.5M0.5Ti0.5OPO4(M = Nb, Ta),related to KTiOPO4

Soft-chemical oxidation of KTiOPO4-like KM(0.5)(V)Ti(0.5)(III)OPO(4) (M = Nb, Ta) using chlorine in CHCl3 is accompanied by partial deintercalation of potassium, yielding K(0.5)MV(0.5)Ti(0.5)(IV)OPO(4) compounds which are new non-linear optical materials that exhibit efficient second-harmonic generation of 1064 nm radiation, as does KTiOPO4.

Mo3O5(OH)(2)(AsO4)2: A new solid with a structure related to beta VOPO4

Mo3O5(OH)(2)(AsO4)(2) was prepared at 100 degrees C from an aqueous solution of MoO3 containing arsenic and nitric acids. It crystallises in the monoclinic system, a = 13.024(1)Angstrom, b = 7.2974 (2) Angstrom, c = 13.281(1) Angstrom, beta = 121.124(8)degrees, Z = 4, space group C2/c. The structure was determined by Rietveld refinement from X-ray powder diffraction data. The three-dimensional structure is built up from MoO6 and MoO5OH octahedra and AsO4 tetrahedra sharing corners. The octahedra share two opposite vertices forming zigzag chains that run parallel to [10(1) over bar]. Each AsO4 tetrahedron is connected to four octahedra, two of which belong to the same chain, thus linking three chains. The resulting covalent framework is similar to that of beta VOPO4 in which one tetrahedral P site for every three is empty. The two protons are likely to be bonded to two (out of four) unshared oxygen atoms surrounding this empty site. All the Mo atoms are strongly off-centred in the octahedra; and the off-centring is disordered. The disorder is discussed in terms of Mo shifts perturbed by a disordered hydrogen bonding scheme.

Novel ABO(3) oxides related to perovskite and YAlO3 structure types in the La-B-V-O (B = Ni, Cu) systems

The synthesis, structure and magnetic properties of mixed-metal oxides of ABO(3) composition in the La-B-V-O (B = Ni, Cu) systems are described in the present paper. While the B = Ni oxides adopt GdFeO3-like perovskite structure containing disordered nickel and vanadium at the octahedral B site, La3Cu2VO9 crystallizes in a YAlO3-type structure. A detailed investigation of the superstructure of nominal La3Cu2VO9 by WDS analysis and Rietveld refinement of powder XRD data reveal that the likely composition of the phase is La13Cu9V4O38.5, where the Cu and V atoms are ordered in a root13a(h) (a(h) = hexagonal a parameter of YAlO3-like subcell) superstructure. Magnetic susceptibility data support the proposed superstructure consisting of triangular Cu-3 clusters. At low temperatures, the magnetic moment corresponds to S = 1/2 per Cu-3 cluster, while at high temperatures the behavior is Curie-Weiss like, showing S = 1/2 per copper. The present work reveals the contrasting behavior of La-Cu-V-O and La-Ni-V-O systems: while a unique line-phase related to YAlO3 structure is formed around La3Cu2VO9 Composition in the copper system, a continuous series of perovskite-GdFeO3 solid solutions, LaNi1-xVxO3 for 0 less than or equal to x less than or equal to 1/3 seems to be obtained in the nickel system, where the oxidation state of nickel varies from 3+ to 2+.

Li3MRuO5 (M = Co, Ni), new lithium-rich layered oxides related to LiCoO2: promising electrochemical performance for possible application as cathode materials in lithium ion batteries

We describe the synthesis and crystal structure of Li3MRuO5 (M = Co and Ni), new rock salt related oxides. Both the oxides crystallize in the layered LiCoO2 (alpha-NaFeO2) structure, as revealed by powder XRD data. Magnetic susceptibility data suggest that the oxidation states of transition metals are Li3Co3+(ls)Ru4+(ls) O-5 (ls = low spin) for the M = Co compound and Li3Ni2+Ru5+O5 for the M = Ni compound. Electrochemical investigations of lithium deintercalation-intercalation behaviour reveal that both Co and Ni phases exhibit attractive specific capacities of ca. 200 mA h g(-1) at an average voltage of 4 V that has been interpreted as due to the oxidation of Co3+ and Ru4+ in Li3CoRuO5 and Ni2+ to Ni4+ in the case of Li3NiRuO5. Thus, a different role of Ru ions is played in the isostructural oxides. Finally, in both cases evidence of irreversible behaviour above 4.2 V is observed and interpreted as formation of high valent ions or alternatively oxidation of oxide ions.

Revisiting some physics issues related to the new mass limit for magnetized white dwarfs

We clarify important physics issues related to the recently established new mass limit for magnetized white dwarfs which is significantly super-Chandrasekhar. The issues include, justification of high magnetic field and the corresponding formation of stable white dwarfs, contribution of the magnetic field to the total density and pressure, flux freezing, variation of magnetic field and related currents therein. We also attempt to address the observational connection of such highly magnetized white dwarfs.

Involvement of S-cerevisiae Rpb4 in subset of pathways related to transcription elongation

Yeast Rpb4, a subunit of RNA pol II is not essential for viability but is involved in multiple cellular phenotypes such as temperature sensitivity, enhanced pseudohyphal morphology, and decreased sporulation. Both in vivo and in vitro studies strongly support involvement of Rpb4 in transcription initiation, while its role in transcription elongation is not entirely consistent. Here we show that Rpb4 is not required for recruitment of RNA pol II on the coding region of YLR454w, a representative long gene. Yet we find strong genetic interaction of rpb4 Delta with mutants in many transcription elongation factors such as Paf1, Spt4, Dst1, Elp3 and Rpb9. We demonstrate that, Rpb4 interacts functionally with Paf1 to affect the transcription elongation of the FKS1 gene. Our results suggest that while Rpb4 is not required for general transcription elongation, it could support transcription elongation for specific of class of genes by interaction with other elongation factors. (C) 2014 Elsevier B.V. All rights reserved.

An experimental study on loading rate effect on acoustic emission based b-values related to reinforced concrete fracture

This article reports on analysis of fracture processes in reinforced concrete (RC) beams with acoustic emission (AE) technique. An emphasis was given to study the effect of loading rate on variation in AE based b-values with the development of cracks in RC structures. RC beams of length 3.2 m were tested under load control at a rate of 4 kN/s, 5 kN/s and 6 kN/s and the b-value analysis available in seismology was used to study the fracture process in RC structures. Moreover, the b-value is related to the strain in steel to assess the damage state. It is observed that when the loading rate is higher, quick cracking development lead to rapid fluctuations and drops in the b-values. Also it is observed that concrete behaves relatively more brittle at higher loading rates (or at higher strain rates). The average b-values are lower as a few but larger amplitudes of AE events occur in contrast to more number of low amplitude AE events occur at low loading rates (or at low strain rates). (C) 2014 Elsevier Ltd. All rights reserved.

Tungsten-based nanomaterials (WO3 & Bi2WO6): Modifications related to charge carrier transfer mechanisms and photocatalytic applications

Heterogeneous photocatalysis is an ideal green energy technology for the purification of wastewater. Although titania dominates as the reference photocatalyst, its wide band gap is a bottleneck for extended utility. Thus, search for non-TiO2 based nanomaterials has become an active area of research in recent years. In this regard, visible light absorbing polycrystalline WO3 (2.4-2.8 eV) and Bi2WO6 (2.8 eV) with versatile structure-electronic properties has gained considerable interest to promote the photocatalytic reactions. These materials are also explored in selective functional group transformation in organic reactions, because of low reduction and oxidation potential of WO3 CB and Bi2WO6 VB, respectively. In this focused review, various strategies such as foreign ion doping, noble metal deposition and heterostructuring with other semiconductors designed for efficient photocatalysis is discussed. These modifications not only extend the optical response to longer wavelengths, but also prolong the life-time of the charge carriers and strengthen the photocatalyst stability. The changes in the surface-bulk properties and the charge carrier transfer dynamics associated with each modification correlating to the high activity are emphasized. The presence of oxidizing agents, surface modification with Cu2+ ions and synthesis of exposed facets to promote the degradation rate is highlighted. In depth study on these nanomaterials is likely to sustain interest in wastewater remediation and envisaged to signify in various green energy applications. (C) 2015 Elsevier B.V. All rights reserved.

Deficits in sensory prediction are related to delusional ideation in healthy individuals.

Motor control strongly relies on neural processes that predict the sensory consequences of self-generated actions. Previous research has demonstrated deficits in such sensory-predictive processes in schizophrenic patients and these low-level deficits are thought to contribute to the emergence of delusions of control. Here, we examined the extent to which individual differences in sensory prediction are associated with a tendency towards delusional ideation in healthy participants. We used a force-matching task to quantify sensory-predictive processes, and administered questionnaires to assess schizotypy and delusion-like thinking. Individuals with higher levels of delusional ideation showed more accurate force matching suggesting that such thinking is associated with a reduced tendency to predict and attenuate the sensory consequences of self-generated actions. These results suggest that deficits in sensory prediction in schizophrenia are not simply consequences of the deluded state and are not related to neuroleptic medication. Rather they appear to be stable, trait-like characteristics of an individual, a finding that has important implications for our understanding of the neurocognitive basis of delusions.

Issues and options related to management of Silver Springs rhesus macaques

Management options for the Silver Springs free-ranging rhesus macaque population range from removal to active maintenance of the population in situ. Selection of a management option is dependent upon which issues are perceived to be true problems. Management options are presented along with their effectiveness in dealing with issues previously described.(31 page document)

Running Pace Decrease during a Marathon Is Positively Related to Blood Markers of Muscle Damage

Background: Completing a marathon is one of the most challenging sports activities, yet the source of running fatigue during this event is not completely understood. The aim of this investigation was to determine the cause(s) of running fatigue during a marathon in warm weather. Methodology/Principal Findings: We recruited 40 amateur runners (34 men and 6 women) for the study. Before the race, body core temperature, body mass, leg muscle power output during a countermovement jump, and blood samples were obtained. During the marathon (27 uC; 27% relative humidity) running fatigue was measured as the pace reduction from the first 5-km to the end of the race. Within 3 min after the marathon, the same pre-exercise variables were obtained. Results: Marathoners reduced their running pace from 3.5 6 0.4 m/s after 5-km to 2.9 6 0.6 m/s at the end of the race (P,0.05), although the running fatigue experienced by the marathoners was uneven. Marathoners with greater running fatigue (. 15% pace reduction) had elevated post-race myoglobin (1318 6 1411 v 623 6 391 mg L21; P,0.05), lactate dehydrogenase (687 6 151 v 583 6 117 U L21; P,0.05), and creatine kinase (564 6 469 v 363 6 158 U L21; P = 0.07) in comparison with marathoners that preserved their running pace reasonably well throughout the race. However, they did not differ in their body mass change (23.1 6 1.0 v 23.0 6 1.0%; P = 0.60) or post-race body temperature (38.7 6 0.7 v 38.9 6 0.9 uC; P = 0.35). Conclusions/Significance: Running pace decline during a marathon was positively related with muscle breakdown blood markers. To elucidate if muscle damage during a marathon is related to mechanistic or metabolic factors requires further investigation.