Modification of as-cast Al-Mg/B4C composite by addition of Zr

Zirconium was used in Al-Mg/B4C composite to improve compocasting efficiency by increasing particle incorporation. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) results revealed that by addition of zirconium a reaction layer containing Zr, Al, B and C is formed on the interface of B4C-matrix. X-ray diffraction (XRD) analysis of extracted particles unveiled that the ZrB2 phase is the main constituent of this layer. Formation of ZrB2 is an exothermic reaction which can rise temperature locally around particles and agglomerates. Rising temperature around agglomerates in conjunction with turbulent flow of melt facilitates agglomerates wetting and dissolving into molten aluminum. As the result, final product contains more uniformly distributed B4C particles. Besides enhancing compocasting efficiency, addition of Zr and formation of reaction layer by improving particle matrix bonding quality, led to increase in ultimate tensile strength and elongation of the composite around 8% and 30%, respectively. SEM observations of the fracture surfaces confirmed that a proper bonding presents at the interface of particles and matrix in presence of Zr.Peer ReviewedPostprint (author's final draft

Nuclear medicine program progress report for quarter ending September 30, 1996

The reactor production yields of tungsten-188 produced by neutron capture by enriched tungsten-186 in the HFIR and other reactors are nearly an order of magnitude lower than expected by calculation using established cross section values. Since neutron capture of tungsten-188 may be the major factor which significantly reduces the observed yields of tungsten-188, the authors have evaluated the possible burn-up cross section of the tungsten-188 product. Tungsten-189 was produced by irradiating a radioactive target containing a known amount of {sup 188}W. In order to reduce the radiation level to an acceptable level (90% of {sup 188}Re, which is the decay product of {sup 188}W, prior to irradiation. They were able to confirm the two predominant {gamma}-rays in the decay of {sup 189}W, 260.1 {+-} 1.4 and 421.5 {+-} 1.6 keV. By following the decay of these {gamma}-rays in two sets of experiments, a half-life of 10.8 {+-} 0.3 m was obtained for {sup 189}W. Based on a knowledge of the {sup 188}W content of target (52.6 mBq), neutron flux of 5 {times} 10{sup 13} n {center_dot} s{sup {minus}1} {center_dot} cm{sup {minus}2}, irradiation time of 10 min and with the assumption of 100% intensity for 260.1 and 421.5 keV {gamma}-rays, a cross-section of 12.0 {+-} 2.5 b was calculated for burn-up cross-section of {sup 188}W, which helps explain the greatly reduced production yields of {sup 188}W

A review of the ecological and socioeconomic characteristics of trophy hunting across Asia

The continuing debates about trophy hunting should be underpinned by an understanding of at least the basic characteristics of the practice (e.g. species, quotas, areas, prices). Whilst many countries in Asia have established trophy hunting programmes of considerable importance to conservation and local livelihoods, there remains some ambiguity over the extent of trophy hunting in Asia as its basic characteristics in each country have not been compiled. In this study, we compile information on various ecological and socioeconomic characteristics of trophy hunting of mammals for countries across Asia by reviewing published and unpublished literature, analysing trade data, and obtaining contributions from in-country contacts. Across Asia, established trophy hunting programmes exist in at least 11 countries and target at least 30 species and one hybrid (incl., five Vulnerable and one Endangered species). Trophy hunting in these countries varies markedly in areas (e.g. >1 million km2 in Kazakhstan, 37% of country, vs. 1325 km2 in Nepal, <1% of country) and annual offtakes (e.g. Kazakhstan: 4500 individuals from 4 of 5 trophy species; Pakistan: 229 from 4 of 7; Mongolia: 155 from 6 of 9; Tajikistan: 126 from 3 of 6; Nepal: 22 from 3 of the 4 that are trophy hunted in practice). Permit prices also vary across species and countries, with domestic and international hunters sometimes charged different rates. Hunters from the USA appear overwhelmingly prominent among international clients. National legislations typically mandate a proportion of trophy hunting revenue to accrue locally (range: 40–100%). We provide five key recommendations for research to inform trophy hunting policy in Asia: (1) Ecological impact assessments; (2) Socioeconomic impact assessments; (3) Evaluations of the contributions of trophy hunting to conservation spending; (4) Evaluations of the contributions of trophy hunting to the post-2020 Global Biodiversity Framework; (5) Further examinations of perceptions of trophy hunting

Nuclear medicine program progress report for quarter ending March 31, 1995

In this report the conditions for ``direct`` labeling of the anti-granulocyte (MAb) BW 250/183 monoclonal antibody with rhenium-188 (Re-188) from a generator are described. Re-188-BW 250/183 is of interest for potential use for bone marrow ablation. The labeling time, temperature, pH, and the amount of tin and citric acid were optimized utilizing IgG. Radiolabeling yields of greater than 97% were achieved using 1 mL of a phthalate/tartrate buffer (pH 5.{und M}=?), 250 {micro} g BW 250/183, 1.0 mg citric acid, 400 {micro} g tin (II) chloride, and 1 mL of the tungsten-188/rhenium-188 generator eluent (200--800 {micro} Ci of Re-188). Analysis of the Re-188-labeled IgG and BW 250/183 was performed by Instant Thin Layer Chromatography (ITLC), Sephadex purification and High Performance Liquid Chromatography (HPLC). When the labeling was performed at room temperature or 37 C, in vitro stability studies performed in HSA solution, cysteine solution, 6 {und M} urea solution and a 1% casein solution showed that the Re-188 label demonstrated a similar stability profile in all solutions. Initial studies indicate that Re-188-BW 250/183 retained {approximately} 90% of immunoreactivity when compared to the technetium-99m labeled antibody prepared from the same kit. During this period, several radioisotopes prepared in the ORNL HFIR were also supplied on a cost-recovery basis or provided to collaborators for ongoing collaborative projects. These include tin-117m, processed tungsten-188 and the ORNL alumina-based tungsten-188/rhenium-188 generators

LRIG1 is a gatekeeper to exit from quiescence in adult neural stem cells

Adult neural stem cells (NSCs) must tightly regulate quiescence and proliferation. Single-cell analysis has suggested a continuum of cell states as NSCs exit quiescence. Here we capture and characterize in vitro primed quiescent NSCs and identify LRIG1 as an important regulator. We show that BMP-4 signaling induces a dormant non-cycling quiescent state (d-qNSCs), whereas combined BMP-4/FGF-2 signaling induces a distinct primed quiescent state poised for cell cycle re-entry. Primed quiescent NSCs (p-qNSCs) are defined by high levels of LRIG1 and CD9, as well as an interferon response signature, and can efficiently engraft into the adult subventricular zone (SVZ) niche. Genetic disruption of Lrig1 in vivo within the SVZ NSCs leads an enhanced proliferation. Mechanistically, LRIG1 primes quiescent NSCs for cell cycle re-entry and EGFR responsiveness by enabling EGFR protein levels to increase but limiting signaling activation. LRIG1 is therefore an important functional regulator of NSC exit from quiescence

Clinico-radiological features, molecular spectrum, and identification of prognostic factors in developmental and epileptic encephalopathy due to inosine triphosphate pyrophosphatase (ITPase) deficiency

Developmental and epileptic encephalopathy 35 (DEE 35) is a severe neurological condition caused by biallelic variants in ITPA, encoding inosine triphosphate pyrophosphatase, an essential enzyme in purine metabolism. We delineate the genotypic and phenotypic spectrum of DEE 35, analyzing possible predictors for adverse clinical outcomes. We investigated a cohort of 28 new patients and reviewed previously described cases, providing a comprehensive characterization of 40 subjects. Exome sequencing was performed to identify underlying ITPA pathogenic variants. Brain MRI (magnetic resonance imaging) scans were systematically analyzed to delineate the neuroradiological spectrum. Survival curves according to the Kaplan–Meier method and log-rank test were used to investigate outcome predictors in different subgroups of patients. We identified 18 distinct ITPA pathogenic variants, including 14 novel variants, and two deletions. All subjects showed profound developmental delay, microcephaly, and refractory epilepsy followed by neurodevelopmental regression. Brain MRI revision revealed a recurrent pattern of delayed myelination and restricted diffusion of early myelinating structures. Congenital microcephaly and cardiac involvement were statistically significant novel clinical predictors of adverse outcomes. We refined the molecular, clinical, and neuroradiological characterization of ITPase deficiency, and identified new clinical predictors which may have a potentially important impact on diagnosis, counseling, and follow-up of affected individuals

Constitutive behavior of an AA4032 piston alloy with Cu and Er additions upon high temperature compressive deformation

The Research and Researchers for Industry (RRi); King Mongkut’s University of Technology Thonbur

An EBSD study of the deformation of service-aged 316 austenitic steel

Electron backscatter diffraction (EBSD) has been used to examine the plastic deformation of an ex-service 316 austenitic stainless steel at 297K and 823K (24 °C and 550 °C)at strain rates 3.5x10-3 to 4 x 10-7 s-1. The distribution of local misorientations was found to depend on the imposed plastic strain following a lognormal distribution at true strains 0.1. At 823 K (550 °C), the distribution of misorientations depended on the applied strain rate. The evolution of lattice misorientations with increasing plastic strain up to 0.23 was quantified using the metrics kernel average misorientation, average intragrain misorientation, and low angle misorientation fraction. For strain rate down to 10-5 s-1 all metrics were insensitive to deformation temperature, mode (tension vs. compression) and orientation of the measurement plane. The strain sensitivity of the different metrics was found to depend on the misorientation ranges considered in their calculation. A simple new metric, proportion of undeformed grains, is proposed for assessing strain in both aged and unaged material. Lattice misorientations build up with strain faster in aged steel than in un-aged material and most of the metrics were sensitive to the effects of thermal aging. Ignoring aging effects leads to significant overestimation of the strains around welds. The EBSD results were compared with nanohardness measurements and good agreement established between the two techniques of assessing plastic strain in aged 316 steel