Influence of contacts on the microwave response of a two-dimensional electron stripe

Electromagnetic response of a finite-width two-dimensional electron stripe with attached metallic side contacts is theoretically studied. It is shown that contacts substantially influence the position, the linewidth, and the amplitude of plasmon-polariton resonances in the stripe. In finite magnetic fields, absorption of the wave with the inactive circular polarization (which is not absorbed in an infinite system without contacts) may become larger than that of the wave with the active polarization. The results are discussed in view of recent microwave experiments in two-dimensional electron systems.Comment: 13 pages, incl. 9 figures, the paper has been substantially modified and extended, new results have been added. Accepted for publication in Phys. Rev.

Drug-tolerant persister cancer cells are vulnerable to GPX4 inhibition.

Acquired drug resistance prevents cancer therapies from achieving stable and complete responses. Emerging evidence implicates a key role for non-mutational drug resistance mechanisms underlying the survival of residual cancer 'persister' cells. The persister cell pool constitutes a reservoir from which drug-resistant tumours may emerge. Targeting persister cells therefore presents a therapeutic opportunity to impede tumour relapse. We previously found that cancer cells in a high mesenchymal therapy-resistant cell state are dependent on the lipid hydroperoxidase GPX4 for survival. Here we show that a similar therapy-resistant cell state underlies the behaviour of persister cells derived from a wide range of cancers and drug treatments. Consequently, we demonstrate that persister cells acquire a dependency on GPX4. Loss of GPX4 function results in selective persister cell ferroptotic death in vitro and prevents tumour relapse in mice. These findings suggest that targeting of GPX4 may represent a therapeutic strategy to prevent acquired drug resistance

Superradiant Decay of Cyclotron Resonance of Two-Dimensional Electron Gases

We report on the observation of collective radiative decay, or superradiance, of cyclotron resonance (CR) in high-mobility two-dimensional electron gases in GaAs quantum wells using time-domain terahertz magnetospectroscopy. The decay rate of coherent CR oscillations increases linearly with the electron density in a wide range, which is a hallmark of superradiant damping. Our fully quantum mechanical theory provides a universal formula for the decay rate, which reproduces our experimental data without any adjustable parameter. These results firmly establish the many-body nature of CR decoherence in this system, despite the fact that the CR frequency is immune to electron-electron interactions due to Kohn's theorem.Comment: 5 pages, 4 figure

New data on the fauna of the owlets (Lepidoptera: Noctuidae s. l.) of Kabardino-Balkaria

Based on the unpublished data from the collection of Zoological Institute RAS and collections of A.A. Bolov in 2005, the preceding species list (Nolidae, Erebidae, Noctuidae) of Kabardino-Balkaria (Poltavsky, Nekrasov, 2002) is here complemented by 30 more species. Now 226 species are known for the fauna of the region, what is approximately 50-60% of the estimated fauna there. One species,Tarachidia candefacta, was found in Central Caucasus for the first tim

Contribution to the knowledge of the fauna of noctuoid moths (Lepidoptera: Noctuoidea) of Kyrgyzstan

The paper contains data about 354 species of owlet moths, collected in 2017–2020 in Kyrgyzstan. This work is based on the examination of 4043 specimens, from which genitalia for 600 specimens were dissected. The following number of species is recorded for various territories of the country for the first time: 12 species for Kyrgyzstan; 27 species for West TianShan; eight species for Central Tian-Shan; 29 species for Inner Tian-Shan; one species for North Tian-Shan; 10 species for Alai. In total, 878 species of moths are known in the fauna of Kyrgyzstan. Due to the intermediate position of Kyrgyzstan between Kazakhstan and Tajikistan we can predict an average species number in Kyrgyzstan as between 950 and 1000 species. Thus, the fauna of Noctuoidea of this country is studied by 80–90% to the present time

Making microscopy count: quantitative light microscopy of dynamic processes in living plants

First published: April 2016This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Cell theory has officially reached 350 years of age as the first use of the word ‘cell’ in a biological context can be traced to a description of plant material by Robert Hooke in his historic publication “Micrographia: or some physiological definitions of minute bodies”. The 2015 Royal Microscopical Society Botanical Microscopy meeting was a celebration of the streams of investigation initiated by Hooke to understand at the sub-cellular scale how plant cell function and form arises. Much of the work presented, and Honorary Fellowships awarded, reflected the advanced application of bioimaging informatics to extract quantitative data from micrographs that reveal dynamic molecular processes driving cell growth and physiology. The field has progressed from collecting many pixels in multiple modes to associating these measurements with objects or features that are meaningful biologically. The additional complexity involves object identification that draws on a different type of expertise from computer science and statistics that is often impenetrable to biologists. There are many useful tools and approaches being developed, but we now need more inter-disciplinary exchange to use them effectively. In this review we show how this quiet revolution has provided tools available to any personal computer user. We also discuss the oft-neglected issue of quantifying algorithm robustness and the exciting possibilities offered through the integration of physiological information generated by biosensors with object detection and tracking

Materials on the Lepidoptera fauna of the Dagestan Republic (Northeastern Caucasus, Russia): autumn aspect (Insecta: Lepidoptera)

The article provides the list of Lepidoptera (the families: Cossidae, Coleophoridae, Choreutidae, Ethmiidae, Pterophoridae, Pyralidae, Crambidae, Lemoniidae, Lasiocampidae, Drepanidae, Geometridae, Sphingidae, Erebidae, Noctuidae, Lycaenidae, Nymphalidae, Pieridae), collected in four localities in the Republic of Dagestan in September 2020. In total, 207 species have been recorded. Five species are reported for the fauna of Russia for the first time: Casignetella texanella (Chambers, 1878) (Coleophoridae), Agriphila cyrenaicellus (Ragonot, 1887), Thyridiphora furia (Swinhoe, 1884), Haritalodes derogata (Fabricius, 1775) (Crambidae), and Scopula minorata (Boisduval, 1833) (Geometridae); 23 species - for the fauna of Eastern Caucasus: Perygra glaucicolella (Wood, 1892), Ecebalia halophilella (Zimmermann, 1926), E. linosyris (E. Hering, 1937), Ionescumia clypeiferella (O. Hofmann, 1871), Carpochena trientella (Christpoh, 1872) (Coleophoridae), Tebenna micalis (Mann, 1857) (Choreutidae), Ethmia candidella (Alpheraky, 1908) (Ethmiidae), Stenoptilia zophodactyla (Duponchel, 1838), Stenoptilodes taprobanes (Felder & Rogenhofer, 1875), Crombrugghia laetus (Zeller, 1847) (Pterophoridae), Glyptoteles leucacrinella Zeller, 1848, Cadra calidella (Guenée, 1845), (Pyralidae), Agriphila selasella (Hübner, 1813), Agriphila tolli (Bleszynski, 1952), Agriphila poliellus (Treitschke, 1832), Pediasia contaminella (Hübner, 1796), Pediasia fascelinella (Hübner, [1813]), Uresiphita gilvata (Fabricius, 1794), Antigastra catalaunalis (Duponchel, 1833) (Crambidae), Watsonalla binaria (Hufnagel, 1767) (Drepanidae), Idaea degeneraria erschoffi (Christoph, 1872), Scopula nigropunctata (Hufnagel, 1767), and Rhodometra sacraria (Linnaeus, 1767) (Geometridae)