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The electronic behaviour of complex oxides such as LaNiO3 depends on many intrinsic and extrinsic factors, making it challenging to identify microscopic mechanisms. Here the authors demonstrate the influence of oxygen vacancies on the thickness-dependent metal-insulator transition of LaNiO3 films.

Planar magnesium diboride Josephson junctions are fabricated using focused helium ion beam irradiation. A single track of ion irradiation with a 30 kV He+ beam with nominal beam diameter < 0.5 nm is used to create a normal-metal barrier on a MgB2 film deposited by hybrid physical-chemical vapor deposition. Josephson coupling is observed below the critical temperature of the electrodes for a He+ doses between 8x1015/cm2 to 4x1016/cm2. Analysis of the temperature dependence of the normal resistance and critical voltage of the junctions shows highly uniform barriers with nearly ideal resistively-shunted junction behavior for higher-dose junctions, while nonequilibrium effects dominate the properties of lower-dose junctions over most of the temperature range. These results demonstrate that focused helium ion beam irradiation can produce high-quality proximity-coupled MgB2 Josephson junctions with tailorable properties, promising for use in superconducting devices and circuits.

Background: Angiotensin converting enzyme inhibitors (ACEIs) are known to induce anemia following renal transplantation, dialysis and in renal failure patients. It seems that ACEIs cause anemia via inhibition of erythropoietin synthesis or inhibiting normal proliferation of early erythroid progenitors, which are normally stimulated by angiotensin converting enzyme. There are few reports on how ACEIs induce anemia in non-azotemic diabetic patients. We studied the effect of enalapril on inducing anemia in non-azotemic diabetic patients. Methods: This study included 94 diabetic non-azotemic patients (serum creatinine (sCr) ?1.5 mg/dl by jaffe reaction). Patients were divided into two groups, the first; with clinical proteinuria (P+ ) having a 24 hour urine protein ?300 mg or positive urine dipstick for protein, at least on two of three times tested, with an interval of 1 month and the second group without any signs of clinical proteinuria (P- ). Only 32 patients completed the course of study; 17 as P+ and 15 as P-. Patients in both groups received 10 mg enalapril daily; and every 3 months, the dose was doubled until the dose of 40 mg/day was reached, unless any side effects emerged. Hemoglobin concentration (Hb), sCr and serum potassium (K+) were also checked regularly. Data were analyzed using t-Student test, paired t test, and chi-square test. A p value < 0.05 was considered as significant. Results: Both groups of patients were matched from the standpoint of age and sex. The average baseline sCr in P+ and P- groups were 0.8 ± 0.19 mg/dl and 0.8 ± 0.18 mg/dl respectively.( p = 0.97) After the study was completed, the average baseline sCr rose to 0.99±0.19 and 0.92±0.22 mg/dl in P+ and P- groups respectively. In P+ group, mean Hb was 14.1 ±1.30 g/dl and 13.9 ± 0.99g/dl before and after the study respectively.(p = 0.28) The same parameter for the P- group was measured as 14.1±1.00 and 12.9±3.30 before and after the study respectively.(Conclusion: This study shows that enalapril has no significant effect on inducing anemia in non-azotemic diabetic patients. Keywords: Enalapril, Anemia, Diabetes, Proteinuria

We have investigated the normal-state and superconducting properties of Co-doped BaFe2As2 (Ba122) and MgB2 thin films irradiated at room temperature using a 30 keV focused He+ ion beam with doses between 1012 and 1017 cm2. We show that superconductivity is suppressed and the normal-state resistivity is increased upon irradiation. The critical dose for the complete suppression of superconductivity is ∼5 × 1014 cm−2 for Ba122 and ∼8 × 1015 cm−2 for MgB2. The dependence of the normal-state and superconducting properties on irradiation dose is discussed, taking into account the spatial distribution of ion-induced damage. Hillock formation due to the substrate swelling, arising from the He+ ions stopped in the substrate, is also observed. The findings provide guidelines for exploiting focused He+ ion beam irradiation in fabricating iron pnictide and MgB2 planar Josephson junctions. [ABSTRACT FROM AUTHOR]

Modern science is dependent on imaging on the nanoscale, often achieved through processes that detect secondary electrons created by a highly focused incident charged particle beam. Multiple types of measurement noise limit the ultimate trade-off between the image quality and the incident particle dose, which can preclude useful imaging of dose-sensitive samples. Existing methods to improve image quality do not fundamentally mitigate the noise sources. Furthermore, barriers to assigning a physically meaningful scale make the images qualitative. Here, we introduce ion count-aided microscopy (ICAM), which is a quantitative imaging technique that uses statistically principled estimation of the secondary electron yield. With a readily implemented change in data collection, ICAM substantially reduces source shot noise. In helium ion microscopy, we demonstrate 3[Formula: see text] dose reduction and a good match between these empirical results and theoretical performance predictions. ICAM facilitates imaging of fragile samples and may make imaging with heavier particles more attractive., Competing Interests: Competing interests statement:Schultz/Ionwerks owns patents on secondary electron detector designs and methods of use in correlated secondary electron imaging and ion scattering time-of-flight measurements.

The first experimental realization of the intrinsic (not dominated by defects) charge conduction regime in lead-halide perovskite field-effect transistors (FETs) is reported. The advance is enabled by: i) a new vapor-phase epitaxy technique that results in large-area single-crystalline cesium lead bromide (CsPbBr 3 ) films with excellent structural and surface properties, including atomically flat surface morphology, essentially free from defects and traps at the level relevant to device operation; ii) an extensive materials analysis of these films using a variety of thin-film and surface probes certifying the chemical and structural quality of the material; and iii) the fabrication of nearly ideal (trap-free) FETs with characteristics superior to any reported to date. These devices allow the investigation of the intrinsic FET and (gated) Hall-effect carrier mobilities as functions of temperature. The intrinsic mobility is found to increase on cooling from ≈30 cm 2 V -1 s -1 at room temperature to ≈250 cm 2 V -1 s -1 at 50 K, revealing a band transport limited by phonon scattering. Establishing the intrinsic (phonon-limited) mobility provides a solid test for theoretical descriptions of carrier transport in perovskites, reveals basic limits to the technology, and points to a path for future high-performance perovskite electronic devices., (© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

SARS-CoV-2 virions enter the host cells by docking their spike glycoproteins to the membrane-bound Angiotensin Converting Enzyme 2. After intracellular assembly, the newly formed virions are released from the infected cells to propagate the infection, using the extra-cytoplasmic ACE2 docking mechanism. However, the molecular events underpinning SARS-CoV-2 transmission between host cells are not fully understood. Here, we report the findings of a scanning Helium-ion microscopy study performed on Vero E6 cells infected with mNeonGreen-expressing SARS-CoV-2. Our data reveal, with unprecedented resolution, the presence of: (1) long tunneling nanotubes that connect two or more host cells over submillimeter distances; (2) large scale multiple cell fusion events (syncytia); and (3) abundant extracellular vesicles of various sizes. Taken together, these ultrastructural features describe a novel intra-cytoplasmic connection among SARS-CoV-2 infected cells that may act as an alternative route of viral transmission, disengaged from the well-known extra-cytoplasmic ACE2 docking mechanism. Such route may explain the elusiveness of SARS-CoV-2 to survive from the immune surveillance of the infected host., (© 2022. The Author(s).)