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Abstract Recent published literature dealing with FeS 2 pyrite (thin films and single crystals) faces a few and relevant issues: the low photovoltage presented by pyrite (mainly related to the singular nature of its surface), the not yet clearly defined way of making available n and p type reliable samples and the relevance of their stoichiometry. To address the second and third issues, Fe thin films, Ti/Fe and Co/Fe bilayers deposited on sodalime glass and amorphous quartz substrates have been sulfurated at different temperatures (T s) (T s ≲ 600°C) during 20 h to obtain pyrite thin films. Seebeck coefficient and Hall Effect measurements have been carried out at room temperature with the sulfurated samples. It has been found that sulfurated Ti/Fe on sodalime glass presents a change of the Seebeck coefficient sign (from negative to positive) due to a strong interaction of the Ti layer with the substrate, which is not present in the Ti/Fe samples deposited on amorphous quartz. As a consequence of the interaction, a new TiO 2 layer is formed between the sodalime glass substrate and the pyrite layer. Sulfurated Co/Fe bilayers on sodalime glass show a coherent behavior according to the obtained results and previously published works. They all appear to be n -type semiconductors when T s ≳ 175°C. Non-intentionally doped Fe thin films on sodalime glass behave in a non-conclusive fashion from the point of view of their electrical transport characterization. The Seebeck coefficient (S) of the sulfurated films appear to be S > 0 for all values of T s. However, the value and sign of the Hall constant behave in a non-reproducible way. Results are discussed on the light of present knowledge of synthetic pyrite thin films growth and doping. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, the gas permeation properties of carbon molecular sieve (CMS) membranes dispersed with palladium nano particles via supercritical CO2 impregnation method were investigated. The palladium nano particles located near the permeation path consisting of slit-like micropore mouth were shown to function mainly as a selective permeation barrier, resulting in the excellent permselectivity for H2/N2 gas pairs. [Copyright &y& Elsevier]

Abstract: Oscillatory thermocapillary flow in liquid bridges of high Prandtl number fluids is investigated experimentally as well as numerically. Heat loss from the free surface is shown to have significant influence on the onset of oscillations. In the present work the surrounding air flow pattern is changed by heating the liquid bridge from the top or from the bottom. The results show that the local free surface heat transfer rate, especially near the hot wall, has strong effects on the oscillations. [Copyright &y& Elsevier]

Abstract: Experiments have been carried out for half-zones of acetone (Pr =4.3) to investigate the effects of evaporative cooling on the flow structures and temperature fields during transition from steady to oscillatory convection. The unstable flow phenomena have been measured using a variety of diagnostic techniques to determine the effects of evaporative cooling on Marangoni convection in liquid bridges of intermediate Prandtl number. The results show that Marangoni convection in acetone liquid bridges with and without strong evaporation becomes unstable due to the same mechanism but the evaporation has a strong stabilizing effect on the onset of oscillatory Marangoni convection. [Copyright &y& Elsevier]

Rearranged during transfection (RET) gene fusions are a validated target in non-small-cell lung cancer (NSCLC). RET-selective inhibitors selpercatinib (LOXO-292) and pralsetinib (BLU-667) recently demonstrated favorable antitumor activity and safety profiles in advanced RET fusion-positive NSCLC, and both have received approval by the US Food and Drug Administration for this indication. Insights into mechanisms of resistance to selective RET inhibitors remain limited. This study was performed at five institutions. Tissue and/or cell-free DNA was obtained from patients with RET fusion-positive NSCLC after treatment with selpercatinib or pralsetinib and assessed by next-generation sequencing (NGS) or MET FISH. We analyzed a total of 23 post-treatment tissue and/or plasma biopsies from 18 RET fusion-positive patients who received an RET-selective inhibitor (selpercatinib, n = 10; pralsetinib, n = 7; pralsetinib followed by selpercatinib, n = 1, with biopsy after each inhibitor). Three cases had paired tissue and plasma samples, of which one also had two serial resistant tissue specimens. The median progression-free survival on RET inhibitors was 6.3 months [95% confidence interval 3.6–10.8 months]. Acquired RET mutations were identified in two cases (10%), both affecting the RET G810 residue in the kinase solvent front. Three resistant cases (15%) harbored acquired MET amplification without concurrent RET resistance mutations, and one specimen had acquired KRAS amplification. No other canonical driver alterations were identified by NGS. Among 16 resistant tumor specimens, none had evidence of squamous or small-cell histologic transformation. RET solvent front mutations are a recurrent mechanism of RET inhibitor resistance, although they occurred at a relatively low frequency. The majority of resistance to selective RET inhibition may be driven by RET-independent resistance such as acquired MET or KRAS amplification. Next-generation RET inhibitors with potency against RET resistance mutations and combination strategies are needed to effectively overcome resistance in these patients. • Resistance is a major challenge in RET fusion-positive lung cancer treated with RET tyrosine kinase inhibitors (TKIs). • RET mutations involving the solvent front residue G810 are a recurrent yet infrequent mechanism of resistance to RET TKIs. • The majority of resistance to selective RET inhibition is driven by RET-independent resistance, such as MET amplification. • RET TKIs with potency against RET solvent front mutations and combination strategies are needed to overcome resistance. [ABSTRACT FROM AUTHOR]

Abstract This study describes a patient who experienced hepatobiliary Mycobacterium avium infection associated with neutralizing anti–interferon gamma (IFN-γ) autoantibodies during treatment for disseminated M. avium disease. Hepatobiliary M. avium infection should be considered in jaundiced patients with neutralizing anti–IFN-γ autoantibodies, including those receiving antimycobacterial therapy for disseminated M. avium disease. [ABSTRACT FROM AUTHOR]

Abstract: Yttrium aluminium perovskite doped with rare earth ions is a promising material for several technological applications. It is considered as direct replacement for Yttrium Aluminum Garnet (YAG) owing to its structural simplicity and lasing property. It is also known for its mechanical and optical properties. High purity micro crystalline R:YAlO3 (R=Nd3+, Eu3+ and Er3+) is synthesized by employing hydrothermal supercritical fluid technique. The resultant materials were characterized using powder X-ray diffraction for structure and phase identification, scanning electron microscopy and energy dispersive X-ray analysis were performed for particle morphology, phase purity and stoichiometry. These monodispersed polycrystalline materials show high degree of phase purity, good control over the concentration of dopants and exhibit well developed morphological features. [Copyright &y& Elsevier]

Abstract: Compositionally uniform 10mm diameter Si0.5Ge0.5 bulk crystals were grown by the traveling liquidus-zone (TLZ) method which we developed for the alloy crystal growth. Axial compositional variation was less than 0.5at% for the length of 12mm and radial one was less than 0.3at% and showed excellent compositional uniformity. The average full width at half maximum of X-ray rocking curves for 004 diffraction measured across a disk is less than 36arcsec (0.01°) at a distance of 3.5mm away from the seed/crystal interface. This shows high crystallinity and promise of TLZ-grown crystals as substrates for CMOS devices using n-channels of strained Si thin films and p-channels of strained Ge thin films. [Copyright &y& Elsevier]

Abstract: Numerical simulations were conducted to study thermocapillary flows in short half-zone liquid bridges of molten tin with Prandtl number Pr =0.009, under ramped temperature difference. The spatio-temporal structures in the thermocapillary flows in short half-zone liquid bridges with aspect ratios As =0.6, 0.8 and 1.0 were investigated. The first critical Marangoni numbers were compared with those predicted by linear stability analyses (LSA). The second critical Marangoni numbers for As =0.6 and 0.8 were found to be larger than that for As =1.0. The time evolutions of the thermocapillary flows exhibited unusual features such as a change in the azimuthal wave number during the three-dimensional stationary (non-oscillating) flow regime, a change in the oscillation mode during the three-dimensional oscillatory flow regime, and the decreasing and then increasing of amplitudes in a single oscillation mode. The effects of the ramping rate of the temperature difference on the flow modes and critical conditions were studied as well. In this paper, the experimental observability of the critical conditions was also discussed. [Copyright &y& Elsevier]

Abstract: In the growing of In0.3Ga0.7As single crystals, polycrystallization at the initial interface with lattice mismatched seeds is a major problem because no homogeneous In0.3Ga0.7As seed crystals has been obtained and usually GaAs crystals are used as seeds. Hence, a mechanism of polycrystallization at the initial interface was investigated. In this paper, a local misfit stress at the interface is calculated. Then it is compared with the critical resolved shear stress (CRSS). It was determined that the polycrystallization at the initial interface is related to the magnitude of the misfit stress and to that of the CRSS. We discuss growth of larger In0.3Ga0.7As single crystals by avoidance of the polycrystallization at the initial interface. [Copyright &y& Elsevier]

Abstract: The effects of small vibrations on Marangoni convection were investigated experimentally using a liquid bridge of 5 cSt silicone oil with a disk diameter of 7.0mm, and an aspect ratio close to 0.5. Experiments were performed to determine the critical temperature difference data for no vibration case and with small vibrations applied. The experimental results have shown that the effect of small vibrations on the onset of oscillatory flow is small since the critical temperature difference data for different aspect ratios were not affected by the vibrations. To clarify the surface oscillation phenomena induced by external vibrations, a 3-D numerical simulation model was also developed using a level set algorithm to predict the surface oscillations of isothermal silicone oil bridges. By subjecting the liquid bridge to small vibrations, the surface oscillation characteristics were predicted numerically, and the numerical results compared well with the predictions of an analytical model proposed previously. Furthermore, the effect of small vibrations on the surface vibration amplitude of the liquid bridge is also discussed. [Copyright &y& Elsevier]

Abstract: A long-run numerical simulation was carried out on a realistic half-zone liquid bridge model of molten tin, which is identical to JAXA''s (former NASDA) liquid bridge experiment apparatus. Using the time-dependent temperature difference imposed on both ends of supporting iron rods, the simulation numerically reproduces the experiment for a time period of 3100s and enables the study of the two-step bifurcation behavior of Marangoni flow. The present study also evaluates the effect of heating velocity on the bifurcations of the Marangoni flow and indicates that the case with a higher heating velocity gives larger critical Marangoni numbers. Moreover, in this study, we investigate the cause of the second critical Marangoni number and critical frequency disagreement between the experimental results and numerical results, and indicate that the second critical Marangoni number determined through free surface temperature oscillations in the experiment may not correspond to the exact onset of oscillatory Marangoni flow. [Copyright &y& Elsevier]

Abstract: It is indispensable to estimate a diffusion coefficient in a solution zone in order to grow a homogeneous crystal by using the traveling liquidus-zone (TLZ) method. To estimate the diffusion coefficient of Ge in the SiGe solution zone, result of a two-dimensional numerical simulation is compared with an experimental result. From the comparison, the diffusion coefficient is estimated to be 9.5×10−5 cm2/s. By using this coefficient, a sample translation rate for obtaining a homogeneous SiGe crystal is determined. By translating samples with appropriate rates, homogeneous Si0.5Ge0.5 crystals are successfully grown. The typical Ge composition is 0.496±0.006 for more than 13mm long. The experimental result shows the homogeneity of ±1.2% in the mole fraction. This deviation corresponds to the variation of less than ±0.03% in the lattice constant. Since this variation is negligibly small, the homogeneity is excellent. Thus it is found that the TLZ method is the universal growth technique, which is applicable to the crystal growth of not only the III–V compounds but also the IV–IV compounds. [Copyright &y& Elsevier]

Abstract: In order to obtain a homogeneous crystal by using the traveling liquidus-zone (TLZ) method, a conventional one-dimensional model is used to determine an appropriate sample translation rate. Although the conventional model predicts the appropriate translation rate, the latent heat effect is unknown since the conventional model is based on pure solution growth. Therefore, a new model including the latent heat is introduced to investigate the latent heat effect. By considering the new model, the maximum latent heat effect αmax is obtained. The αmax is negligibly small under the condition that the InAs mole fraction is far enough from 0 or 1 in the case of an InGaAs crystal. In order to estimate the actual latent heat effect α, one-dimensional numerical simulations with and without the latent heat are carried out. From the numerical results, the applicable limit of the TLZ method is discussed in the case of In0.3Ga0.7As crystals. The growth rate, which is regarded as a pure melt growth, is also discussed by extrapolating the α dependency. [Copyright &y& Elsevier]

The one-dimensional theoretical model of the traveling liquidus-zone (TLZ) method precisely predicts a sample translation rate for obtaining homogeneous crystals. However, no convection-related terms are included into the model. Here, convection influence on mass transport is numerically investigated. The numerical analysis shows that there are two vortices in the zone. In this case, the flow mainly enhances radial mass transport. In order to correctly understand the convection effect on the mass transport, a new index is introduced instead of the Sherwood number. The new index increases with the sample diameter. In the case of the sample diameter of 2 mm, the mass transport by convection is negligibly small as compared with that by diffusion. This is the main reason that the model prediction agrees well with the ground-based experimental results. In order to reduce the convection influence, microgravity condition is considered in the numerical analysis. [Copyright &y& Elsevier]

The effect of free surface heat loss on oscillatory thermocapillary flow is investigated in liquid bridges of high Prandtl number fluids. It is shown experimentally that the critical temperature difference changes by a factor of two to three by changing the air temperature relative to the cold wall temperature. In order to understand the nature and extent of the interaction between the liquid flow and the surrounding air, the heat transfer from the liquid free surface is investigated numerically for the conditions of the present experimental work. The airflow analysis shows that even when the heat loss is relatively weak (the Biot number is unity or smaller), the critical temperature difference is affected appreciably. It is shown that the heat loss effect is significant in widely conducted tests near room temperature and that the critical temperature difference is much larger than the room temperature value when the heat loss is minimized. The analysis suggests that an interaction between the surface heat loss and dynamic free surface deformation near the hot wall is responsible for the observed heat loss effect. [Copyright &y& Elsevier]

The density of liquid and undercooled Y3Al5O12 was measured over a wide temperature range with the help of an electrostatic levitation furnace. The density of a levitated droplet was measured with a ultraviolet-based imaging technique that illuminated the sample throughout all phases of processing, including at elevated temperatures. Over the 1470–2420 K temperature range, the density can be expressed as ρ(T)/(kg m−3)=3.99×103−0.29 (T−Tm)/K (±5 percent) with Tm=2240 K, yielding a volume coefficient of thermal expansion α(T)=7.3×10−5 K−1. [Copyright &y& Elsevier]

We have invented the traveling liquidus-zone method for growing homogeneous mixed crystals. In this method, the solute transport rate is controlled by the temperature gradient at the freezing interface and compositional homogeneity is established easily on the ground, although the actual growth rate is affected by convection in the liquidus zone. Growth rates for producing homogeneous crystals are examined experimentally by changing the temperature gradient in the zone and they are analyzed theoretically. Experimental results agree with numerical analysis qualitatively. [Copyright &y& Elsevier]