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Temperature dependent phase transformation behavior in cobalt from hexagonal close-packed (hcp) to face centered cubic (fcc) has been found to be contradictory to that reported earlier. It is found that hcp phase stabilizes at both low and high temperature (∼ 873 K) while fcc phase is stabilized at ∼ 500 K. At 298 K, hcp Co has been found to be predominant (∼ 70%) where hcp magnetic phase is ∼ 60%. At 973 K, hcp phase is again predominant (∼ 73%), but it is mainly the non-magnetic phase (∼ 67%). Contrary to present results, it was found earlier that fcc phase was stabilized at high temperature and hcp to fcc transformation occured at ∼ 700 K. Present results from perturbed angular correlation measurements, therefore, requires a new theoretical interpretation for Co phase transformation. From present measurements, hyperfine magnetic fields in Co at room temperature for the hcp and fcc phases have been found to be 18.7(6) and 12.8(3) T, much lower than earlier reported results. The hyperfine magnetic fields at 181 Ta impurity atom have been calculated by density functional theory (DFT) employing the full potential (linearized) augmented plane wave method (FP-LAPW). Present calculated results for both hcp and fcc phases corroborate our experimental results. [ABSTRACT FROM AUTHOR]

The recently observed ferroelectricity in thin films of pure and doped Hafnium oxide (HfO2) has initiated a sustaining effort to stabilize its ferroelectric phase which is the polar orthorhombic (o) phase with space group Pca21. This polar o-phase of the oxide does not appear in its phase transition sequence and is also not thought to be stabilized in bulk oxide. Here, we report the stabilization of three o-phases of this oxide in bulk with space groups Pbca, Pca21 and Pbcm in presence of Yttrium (Y) dopant. For inducing o-phase, 10 at% of Y-dopant has been used and temperature mediated phase transformation from monoclinic (m) to o-phase has been observed. The third o-phase with space group Pbcm could be stabilized for the first time in bulk oxide by Y-dopant. All the o-phases in presence of m-phase could be identified by Time Differential Perturbed γ-γ Angular Correlation (TDPAC) Spectroscopy. The TDPAC parameters assigned to Pbcm phase confirm the theoretical modelization for the phase performed by Wien2K calculation based on Density Functional Theory (DFT). The present work reports the possibility of stabilizing different o-phases including polar one and shows the widening of scope of this oxide for future ferroelectric applications. [ABSTRACT FROM AUTHOR]

Our aim is to study critical point equation conjecture on a compact (k; Ā)-almost co-Kahler manifold. We prove that if a compact (k; Ā)-almost co- Kahler manifold of dimension greater than three satisfies critical point equation, then either is constant or the manifold is an Einstein manifold provided k < 0. [ABSTRACT FROM AUTHOR]

We report on the study of hafnium oxide thin films grown by pulsed laser deposition at various partial oxygen pressures by Time Differential Perturbed Angular Correlations using the nuclear probe 181Hf(β-)181Ta to determine the nuclear quadrupole interaction (NQI), and by x-ray diffraction. The samples were neutron activated and measured at room temperature as received as well as after annealing in air. All spectra exhibited two to three inequivalent probe sites, even after annealing. At 0.3 mbar oxygen partial pressure and annealing for 5 hs at 1073 K the majority (88%) of the sites exhibited NQI parameters as reported for the bulk monoclinic phase [ωQ = 125.4(2) Mrad/s, η = 0.335(5)]. We can exclude amorphous as well as cubic and tetragonal hafnium oxide phases in the annealed samples. There was no indication of room-temperature ferromagnetism. [ABSTRACT FROM AUTHOR]

Many animals use coloration to communicate with other individuals. Although the signalling role of avian plumage colour is relatively well studied, there has been much less research on coloration in avian bare parts. However, bare parts could be highly informative signals as they can show rapid changes in coloration. We measured bill colour (a ubiquitous bare part) in over 1600 passerine species and tested whether interspecific variation in carotenoid-based coloration is consistent with signalling to potential mates or signalling to potential rivals in a competitive context. Our results suggest that carotenoid bill coloration primarily evolved as a signal of dominance, as this type of coloration is more common in species that live in social groups in the nonbreeding season, and species that nest in colonies; two socio-ecological conditions that promote frequent agonistic interactions with numerous and/or unfamiliar individuals. Additionally, our study suggests that carotenoid bill coloration is independent of the intensity of past sexual selection, as it is not related to either sexual dichromatism or sexual size dimorphism. These results pose a significant challenge to the conventional view that carotenoid-based avian coloration has evolved as a developmentally costly, condition-dependent sexual signal. We also suggest that bare part ornamentation may often signal different information than plumage ornaments. [ABSTRACT FROM AUTHOR]

. Measuring von Willebrand factor (VWF) activity is essential to the diagnosis of von Willebrand disease (VWD). The VWF activity is usually assessed based on measurement of the ristocetin cofactor (VWF:RCo). However, that test is technically challenging and has high intra- and inter-assay variabilities. The HemosIL VWF activity (VWF:AC) is a fully automated assay, recently proposed as a good alternative to VWF:RCo for VWD diagnosis. This study was undertaken to assess this new method. First, the analytical performance of VWF:AC on an automated coagulo-meter (ACLTop) was determined, and then this new method was compared with VWF:RCo and the platelet function analyzer (PFA100) for 160 patients referred for VWD screening. The VWF:AC achieved acceptable precision with within-run and between-run coefficients of variation ranging from 2.3% to 14.1%, and linearity from 10% to 100%. Despite some marked differences between VWF:AC and VWF:RCo for 10 plasmas tested, their agreement for VWD diagnosis was good. The VWF:AC had sensitivity similar to that of PFA100 (close to 100%), but better specificity (97.7% vs. 66% or 60%, depending on the cartridge used). The good analytical performance, and the sensitivity and specificity of VWF:AC to detect VWF deficiency renders it a suitable method for VWD screening. Our findings support VWF:AC use for the diagnostic work-up of VWD, paying close attention to concomitant clinical signs and bleeding score, as recommended for VWD. [ABSTRACT FROM AUTHOR]

A four-detector perturbed angular correlation (PAC) spectrometer has been developed with ultra-fast BaF 2 detectors to acquire four coincidence spectra simultaneously, two at 18° and two at 90°. This spectrometer has double efficiency compared to that of a three-detector set-up. Higher efficiency is desirable for PAC studies in solid state physics where large number of coincidences are required to obtain the PAC spectra with good statistics and is particularly useful when the half-lives of the parent probe nuclei used for PAC measurements are 2-3 days or less as in 111In (2.8 d), 99Mo (2.7 d) and 140La (1.7 d). The performance of the spectrometer has been tested for the HfO2 monoclinic crystal in the temperature range from 77 to 873 K and for the HfF4·3H2O crystal at room temperature. The polycrystalline HfO2 has been synthesized from Hf metal by heating in air. The hydrated hafnium fluoride has been crystallized by dissolving Hf metal in 40% HF and drying slowly at room temperature. [ABSTRACT FROM AUTHOR]

Unconscious patients are frequently referred to radiology departments for computed tomography (CT) of the brain. The objectives of these examinations are to define the underlying cause of impaired consciousness and in some cases to determine the severity of associated brain injury. There is often little history available to guide the clinician or radiologist, particularly in patients referred from the casualty department. In this review, we present the typical CT appearances of adult patients presenting with loss of consciousness for CT examination. We focus on the most common abnormalities that are identified in everyday radiological practice, emphasize important diagnostic signs that may enable a confident diagnosis to be made and discuss when further imaging may be warranted. [Copyright &y& Elsevier]

The behavior of $\text{HfF}_{6}^{2-}$ octahedral complex in HF has been studied in the temperature range from 300 to 77 K by time differential perturbed angular correlation technique. No time dependent spin relaxation has been observed up to 223 K. At 203 and 193 K, definite nuclear spin relaxations while at 77 K a pure static interaction have been observed. These indicate that at temperatures below 223 K, a different phase of the liquid appears. The rotational correlation times characterizing the tumbling motion of the complex in HF have been determined at 203 and 193 K and found to be 1.6 ns and 2.1 ns, respectively from the measured relaxation constants at these temperatures and the value of quadrupole frequency found at 77 K. The value of rotational correlation time found at 203 K disagrees by an order of magnitude with the earlier measured value which was found to be in the picosecond range. [ABSTRACT FROM AUTHOR]

RNA interference, part of a complicated network of interconnected pathways for cellular defence, RNA surveillance and development, has become a powerful tool for the experimental manipulation of gene expression. It is the process by which double-stranded (dsRNA) silences specific gene expression through homology-dependent degradation of cognate mRNA. The dsRNA is converted into 21nt small interfering RNAs (siRNAs), which directs a complex ribonuclease system to substrate mRNA targets. The degradation of the target mRNA is initiated with the cleavage at a position corresponding to the centre of the siRNA. Dissecting individual cellular pathways to reveal the function of numerous proteins is an approach to drug discovery. Interfering RNA (RNAi) serves as a rapid and convenient tool, which works in various organisms. RNAi technology has the potential to facilitate our understanding of biological processes and potentially lead to exciting new drugs.Here we review various experimental approaches adopted with RNAi and possible therapeutic applications. [ABSTRACT FROM AUTHOR]

The lifetimes of the 615 and 619 keV levels in181Ta have been remeasured by using a-delayed coincidence set up with fast plastic (Pilot U) and BaF2 detectors. The presently measured values for both levels have been found to be in strong disagreement with results reported earlier. For the 615 keV level, the half-life has been found to bens in striking contrast to the earlier reported value of 17.6s. The half-life of the 619 keV level has been found to beps, whereas values of 0.87 ns and 2.4 ns were reported previously. The nanosecond half-life of the 615 keV level has been confirmed from a separate measurement by employing a NaI(Tl)-Pilot U detector combination. The importance of lifetime measurements for the 615 keV level in perturbed angular correlation studies is discussed. [ABSTRACT FROM AUTHOR]

Strong evidence of atomic “after effects” following β--decay of 181Hf was observed from perturbed angular correlation (PAC) studies in different viscous and non-viscous molecular solutions and in ionic as well as non-ionic solutions. In non-viscous acetone and H2O solutions, the PAC spectra have been found to be completely different to what was expected considering molecular motions in these media. Similarly, in the glycerol–H2O system, PAC spectra remain significantly unchanged with the change of viscosity indicating that molecular motions are not reflected in these media. Rather, perturbations from the interaction of the nucleus-excited atomic state, which was so far considered to be absent for 181Hf β--decay, have been found to be dominant. The atomic shell recovery times in molecular liquids have been found to be in the range 50–150 nsec. In insulating solid HfCl4 medium, however, the PAC spectrum indicates that the atomic shell following 181Hf β--decay remains unchanged within the lifetime of the intermediate state. The lifetime for the 615 keV level has been remeasured and a value of T1/2=12.1±0.1 nsec only has been obtained. This value, although in strong disagreement with the earlier reported value (17.83 μsec), helps explain atomic “after effects” in 181Hf β--decay. [ABSTRACT FROM AUTHOR]

Systematic measurements of perturbed angular correlation (PAC) for the 133–482 keV cascade of 181Ta have been performed in the viscous media of glycerol, diethylene glycol and ethylene glycol. The similar PAC spectra observed and the same values of different parameters like quadrupole frequency, relaxation constant and anisotropy parameter found (within errors) confirm atomic “after effects” following β--decay of 181Hf in these media. The PAC measurements have also been performed in these media at different viscosities by adding H2O. For the glycerol–H2O system, it is found that atomic recovery time do not changes in the viscosity range of greater than 5 mPa s. In this range of viscosity, the recovery time was measured to be ∼50 nsec. In the low viscosity region (&les;2 mPa s), however, the atomic recovery process becomes faster. In case of diethylene glycol–H2O and ethylene glycol–H2O systems also, it is found that atomic recovery times becomes smaller in the low viscosity region. [ABSTRACT FROM AUTHOR]

Summary Microtubules are cytoskeletal polymers essential for the survival of all eukaryotes. These proteins are the proposed cellular targets of many anticancerous, antifungal and antihelminthic drugs. Sufficient differences exist between the microtubules of kinetoplastid parasites like Leishmania and humans to explore the selective targeting of these proteins for therapeutic purposes. This review describes the basic structure of microtubules and its dynamics in general, with specific insights into leishmanial microtubules, the salient features of microtubule–drug interactions including the specificity of certain drugs for parasitic microtubules. Chemotherapy against leishmanial parasites is failing because of the emergence of drug resistant strains. The possible mechanisms of resistance to antimicrotubule agents along with insights into the role of microtubules in mediating drug resistance in Leishmania are discussed. [ABSTRACT FROM AUTHOR]

Focal adhesion kinase (FAK) was heavily phosphorylated as a function of differentiation of C2C 12 mouse skeletal muscle cells. Insulin caused increases in FAK phosphorylation before stabilization in proliferated cells, while in differentiated cells there was a consistent transient inhibition of FAK phosphorylation before stimulation. The expression level of FAK was unaltered. Specific inhibition of insulin receptor tyrosine kinase activity abolished the insulin-mediated dephosphorylation of FAK. The data strongly indicate that FAK tyrosine phosphorylation necessary for skeletal muscle differentiation, is modulated by insulin. Thus, for the first time, we report the differential regulation of FAK tyrosine phosphorylation by insulin during skeletal muscle differentiation. [ABSTRACT FROM AUTHOR]

Investigates the design and construction of guarded hot plate instruments for measuring heat flow in plane-parallel glass surfaces. Details on the conducting material surrounding the insulating region of the structure; Design considerations for guarded hot plates; Information on the validation process of the development of the measuring instrument.

Morquio syndrome is a rare type of mucopolysaccharidosis. Our patient presented with uncontrolled seizures and gross skeletal deformity. He was suspected to be suffering from mucopolysaccharidosis based on his disease presentation but the diagnosis could be made as Morquio syndrome on the basis of the presence of keratan sulphate in the urine. [ABSTRACT FROM AUTHOR]

Traumatic hip dislocation in the paediatric population is a relatively rare occurrence and constitutes an orthopaedic emergency. A trivial force is all that is required and non-accidental injury should not be necessarily suspected. A case report involving a hip dislocation in a 21-month-old child, the youngest in the recent English literature is detailed. [ABSTRACT FROM AUTHOR]

From temperature dependent perturbed angular correlation (PAC) measurements (77–873 K) in equiatomic TiNi intermetallic alloy, martensitic phase transformations have been observed. Three frequency components corresponding to three different phases of TiNi have been found in the temperature range 298–873 K. The results of quadrupole frequency and asymmetry parameters at room temperature are found to be: ωQ = 14(1) Mrad/s, η = 0 (33%), ωQ = 40.0(5) Mrad/s, η = 0.66(3) (52%) and ωQ = 56.7(3)Mrad/s, η = 0.39(2) (15%). The frequency component with η = 0 and which enhances to ~52% at 373 K can be attributed to the cubic austenite phase. The predominant component (~52%) found at room temperature has been attributed to monoclinic martensitic phase of TiNi and the third component with values of ωQ and η similar to those for the martensitic phase is attributed to the intermediate orthorhombic phase. At 77 K, no intermediate and austenite phases have been found but only the martensite phase is observed at this temperature. From XRD measurements at room temperature also, three phases of TiNi have been observed. [ABSTRACT FROM AUTHOR]

This study evaluates height loss during the day in light of variables assessable through participant self-report. Participants were 19 female and 15 male staff and students who met with us twice with a mean interval between measurement sessions of 6.96 h (SD = 0.86). Hypotheses were evaluated using two-stage least squares regression analysis (SYSTAT 10). Males and females lost similar amounts of height between sessions ( male , x ¯ = 6.9   mm ; female , x ¯ = 7.4   mm ) . Among factors considered to impact overall height loss, sleep duration (Adj. R 2 = 0.181, p = 0.022) and height (Adj. R 2 = 0.121, p = 0.048) were useful in univariate analyses, though they were not significant in any models that included variables other than sex. Judging from log-transformed BMI variation, heavier males and females lost more height ( F (2, 31) = 4.59, Adj. R 2 = 0.179, p = 0.018). Among factors anticipated to reduce height loss by acting prior to morning measurements, only time spent walking was significantly associated ( β = 2.6 ± 0.8 mm, t = 3.16, p = 0.004) when included as a predictor along with sex ( p = 0.17) and log-BMI ( p = 0.003). This model explained about 38% of height loss variance. None of the factors considered as potentially acting between measurement sessions showed statistically significant influences when included in the model just described, though predictor coefficients were in the anticipated direction. Results suggest that self-reported activities may be an important supplement to anthropometric studies, both for planning and later evaluation, particularly in large studies. [ABSTRACT FROM AUTHOR]

High-spin states of neutron-deficient trans-lead nucleus 204 At were populated up to ∼ 8 MeV excitation through the 12 C + 197 Au fusion evaporation reaction. Decay of the associated levels through prompt and delayed γ -ray emissions were studied to evaluate the underlying nuclear structure. The level scheme, which was partly known, was extended further. An isomeric 16 + level with observed mean lifetime τ = 52 ± 5 ns , was established from our measurements. Attempts were made to interpret the excited states based on multi quasiparticle and hole structures involving 2 f 5 / 2 , 1 h 9 / 2 , and 1 i 13 / 2 shell model states, along with moderate core excitation. Magnetic dipole band structure over the spin parity range: 16 + – 23 + was confirmed and evaluated in more detail, including the missing cross-over E2 transitions. Band-crossing along the shears band was observed and compared with the evidence of similar phenomena in the neighbouring 202 Bi , 205 Rn isotones and the 203 At isotope. Based on comparison of the measured B(M1)/B(E2) values for transitions along the band with the semiclassical model based estimates, the shears band of 204 At was established along with the level scheme. [ABSTRACT FROM AUTHOR]

Fish compensate for acid-base disturbances primarily by modulating the branchial excretion of acid-base equivalents, with a supporting role played by adjustment of urinary acid excretion. The present study used metabolic acid-base disturbances in rainbow trout, Oncorhynchus mykiss, to evaluate the role played by cortisol in stimulating compensatory responses. Trout infused with acid (an iso-osmotic solution of 70 mmol L HCl), base (140 mmol L NaHCO) or saline (140 mmol L NaCl) for 24 h exhibited significant elevation of circulating cortisol concentrations. Acid infusion significantly increased both branchial (by 328 μmol kg h) and urinary (by 5.9 μmol kg h) net acid excretion, compensatory responses that were eliminated by pre-treatment of trout with the cortisol synthesis inhibitor metyrapone (2-methyl-1,2-di-3-pyridyl-1-propanone). The significant decrease in net acid excretion (equivalent to enhanced base excretion) of 203 μmol kg h detected in base-infused trout was unaffected by metyrapone treatment. Acid- and base-infusions also were associated with significant changes in the relative mRNA expression of branchial and renal cytosolic carbonic anhydrase (tCAc) and renal membrane-linked CA IV (tCA IV). Cortisol treatment caused changes in CA gene expression that tended to parallel those observed with acid but not base infusion. For example, significant increases in renal relative tCA IV mRNA expression were detected in both acid-infused (~2 x) and cortisol-treated (~10 x) trout, whereas tCA IV mRNA expression was significantly reduced (~5 x) in base-infused fish. Despite changes in CA gene expression in acid- or base-infused fish, neither acid nor base infusion affected CAc protein levels in the gill, but both caused significant increases in branchial CA activity. Cortisol treatment similarly increased branchial CA activity in the absence of an effect on branchial CAc protein expression. Taken together, these findings provide support for the hypothesis that in rainbow trout, cortisol is involved in mediating acid-base compensatory responses to a metabolic acidosis, and that cortisol exerts its effects at least in part through modulation of CA. [ABSTRACT FROM AUTHOR]

Holt-Oram syndrome (HOS) is characterised by skeletal abnormalities of the upper limb & congenital cardiac defects. Here we report a case of one day old male baby with skeletal abnormalities of forearms and hands, atrial septal defect of ostium secundum type and unilateral hypoplastic kidney. Till date, other associated anomalies like extra-hepatic portal hypertension, renal artery malformations etc have been reported with Holt-Oram syndrome, but it is the first case to be reported in association with hypoplastic kidney. [ABSTRACT FROM AUTHOR]