The Large Array Survey Telescope -- System Overview and Performances

The Large Array Survey Telescope (LAST) is a wide-field visible-light telescope array designed to explore the variable and transient sky with a high cadence. LAST will be composed of 48, 28-cm f/2.2 telescopes (32 already installed) equipped with full-frame backside-illuminated cooled CMOS detectors. Each telescope provides a field of view (FoV) of 7.4 deg^2 with 1.25 arcsec/pix, while the system FoV is 355 deg^2 in 2.9 Gpix. The total collecting area of LAST, with 48 telescopes, is equivalent to a 1.9-m telescope. The cost-effectiveness of the system (i.e., probed volume of space per unit time per unit cost) is about an order of magnitude higher than most existing and under-construction sky surveys. The telescopes are mounted on 12 separate mounts, each carrying four telescopes. This provides significant flexibility in operating the system. The first LAST system is under construction in the Israeli Negev Desert, with 32 telescopes already deployed. We present the system overview and performances based on the system commissioning data. The Bp 5-sigma limiting magnitude of a single 28-cm telescope is about 19.6 (21.0), in 20 s (20x20 s). Astrometric two-axes precision (rms) at the bright-end is about 60 (30)\,mas in 20\,s (20x20 s), while absolute photometric calibration, relative to GAIA, provides ~10 millimag accuracy. Relative photometric precision, in a single 20 s (320 s) image, at the bright-end measured over a time scale of about 60 min is about 3 (1) millimag. We discuss the system science goals, data pipelines, and the observatory control system in companion publications.Comment: Submitted to PASP, 15p

Increased hepatic ferritin-H messenger RNA levels correlate with those of c-myc in human hepatocellular carcinoma

Serum ferritin is elevated in many cancers. Using the subtraction-enhanced display technique, we isolated several cDNA clones including ferritin-H which is overexpressed in rat hepatocellular carcinoma (HCC) induced by diethylnitrosamine. We investigated hepatic messenger RNA (mRNA) levels of ferritin-H in patients with HCC, adenoma, cirrhosis and healthy controls in relation to those of oncogene c-myc. Ferritin-H mRNA levels were 2-12 fold higher in tumor tissues than in adjacent non-tumor tissues in 12 of 17 patients with HCC, irrespective of coexisting cirrhosis or viral hepatitis. However, no difference in ferritin-H mRNA levels was found in patients with adenoma, cirrhosis and healthy controls. c-myc mRNA levels were 2-5 ford increased in 11 of 17 HCC patients, and correlated significantly with those of ferritin-H (p <0.001). In situ hybridization showed that the overexpressed ferritin-H mRNA was restricted to the tumor nodules in HCC livers. These findings suggest that overexpression of ferritin-fl in HCC patients, correlated with c-myc, is phenotypically associated with HCC, and could become a useful molecular indicator for human HC

Sustainability marketing beyond sustainable development: towards a degrowth agenda

Drawing on ecological economics, post-development studies, and political ecology, this paper argues that sustainable development notions have run their course within sustainability marketing debates and proposes degrowth as an alternative framework to steer disciplinary debates in new directions. We chart unexplored territory, offering sustainability marketing scholars tools to navigate degrowth-minded policies, transformative frameworks, and business models. In doing so, our work contributes to existing sustainability marketing debates in three ways: first, we respond to the paucity of studies engaging with the political economy of sustainability marketing. Second, we make visible the tensions and contradictions that arise as marketers seek to reconcile imperatives of economic growth and sustainability. Finally, we foreground degrowth as an emerging sustainability proposition, with potential for inspiring the radical set of transformations required to avert catastrophic climate change and keep global temperatures well below +2°C (relative to pre-industrial levels), as pledged in the Paris Agreement

Search for q ∼ 0 order near a forbidden bragg position in bi2.1sr1.9cacu2o8+x with resonant soft x-ray scattering

Identifying what broken symmetries are present in the cuprates has become a major area of research. Many authors have reported evidence for so-called "Q ∼ 0"order that involves broken inversion, mirror, chiral, or time-reversal symmetry that is uniform in space. Not all these observations are well understood and new experimental probes are needed. Here we use resonant soft x-ray scattering (RSXS) to search for Q ∼ 0 order in Bi2.1Sr1.9CaCu2O8+x (Bi-2212) by measuring the region of a forbidden Bragg peak, 0; 0; 3 , which is normally extinguished by symmetry but may become allowed on resonance if valence band order is present. Using circularly polarized light, we found that this reflection becomes allowed on the Cu L3 resonance for temperatures Tc &lt; T &lt; T+, though remains absent in linear polarization and at other temperatures. This observation suggests the existence of spatially uniform valence band order near the pseudogap temperature. In addition, we observed periodic oscillations in the specular reflectivity from the sample surface that resemble thin film interference fringes, though no known film is present. These fringes are highly resonant, appear in all polarizations, and exhibit a period that depends on the location where the beam strikes the sample surface. We speculate that these fringes arise from interaction between some intrinsic valence band instability and extrinsic structural surface morphologies of the material. Our study supports the existence of some kind of Q ∼ 0 broken symmetry state in Bi-2212 at intermediate temperatures. Further studies using a microfocused beam, which could disentangle microscopic effects from macroscopic heterogeneities, are needed to ascertain the universality of the effect

Electron Impact Excitation of the Argon 3p⁵4s Configuration: Differential Cross-Sections and Cross-Section Ratios

New electron-impact differential cross-section (DCS) and DCS ratio measurements for the excitation of the four levels making up the 3p54s configuration of argon are reported at incident electron energies of 14, 15, 17.5, 20, 30, 50 and 100 eV. These cross-sections were obtained using a conventional high resolution electron spectrometer. Elastic electron scattering from argon was used as a calibration standard. Electron-helium DCSs were used to determine the instrumental transmission of the spectrometer. Further checks of the relative shape of these DCS measurements were made using the method of gas mixtures (Ne mixed with Ar). We also present results from new calculations of these DCSs using the R-matrix method, the unitarized first-order many-body theory, the semi-relativistic distorted-wave Born approximation, and the relativistic distorted-wave method. Comparison with available experimental DCSs and DCS ratios is also presented