Supersymmetry Across Nanoscale Heterojunction

We argue that supersymmetric transformation could be applied across the heterojunction formed by joining of two mixed semiconductors. A general framework is described by specifying the structure of ladder operators at the junction for making quantitative estimation of physical quantities. For a particular heterojunction device, we show that an exponential grading inside a nanoscale doped layer is amenable to exact analytical treatment for a class of potentials distorted by the junctions through the solutions of transformed Morse-Type potentials.Comment: 7 pages, 2 figure

COMPARATIVE CHARACTERISTICS OF THE MORPHOLOGICAL CHANGES OF NEPHRON TUBULES AT THE EARLY AND LATE STAGES OF THE CHRONIC OPIOID EFFECT

The aim of the study is the examination of the nephron tubules morphological changes at the early and late stages of the experimental chronic opioid effect. Varying degrees of the morphological changes of proximal convoluted tubules, loops of Henle and distal convoluted tubules under chronic nalbuphine effect in the dynamics have been detected. The materials of the study – kidneys of 56 sexually mature male-rats. The experimental animals received daily intramuscular nalbuphine injections for 98 days. From the first to the fourteenth day of the experiment the dose of nalbuphine was 0,212 mg/kg. Every next two weeks nalbuphine injections were done in increasing doses. For histological investigation was used commonly agreed method. The colouring was performed using hematoxylin and eosin as well as azan by Heidenhain's method. Varying degrees of morphological changes of proximal convoluted tubules, loops of Henle and distal convoluted tubules under continuous nalbuphine injection in the dynamics have been detected. The most vivid alterative changes can be observed in proximal convoluted tubules both: at the early and late stages of the experiment. At the early stages as of the 14th day of the experiment signs of granular dystrophy appear, as of the 28th day – necrotic changes, progressing further at the late stages of the experiment. The loops of Henle undergo sporadic destructive changes at the early stages and at the beginning of the late stage of the experiment. Distal convoluted tubules have been necrotic altered only at the late stages of the experiment.The aim of the study is the examination of the nephron tubules morphological changes at the early and late stages of the experimental chronic opioid effect. Varying degrees of the morphological changes of proximal convoluted tubules, loops of Henle and distal convoluted tubules under chronic nalbuphine effect in the dynamics have been detected. The materials of the study – kidneys of 56 sexually mature male-rats. The experimental animals received daily intramuscular nalbuphine injections for 98 days. From the first to the fourteenth day of the experiment the dose of nalbuphine was 0,212 mg/kg. Every next two weeks nalbuphine injections were done in increasing doses. For histological investigation was used commonly agreed method. The colouring was performed using hematoxylin and eosin as well as azan by Heidenhain's method. Varying degrees of morphological changes of proximal convoluted tubules, loops of Henle and distal convoluted tubules under continuous nalbuphine injection in the dynamics have been detected. The most vivid alterative changes can be observed in proximal convoluted tubules both: at the early and late stages of the experiment. At the early stages as of the 14th day of the experiment signs of granular dystrophy appear, as of the 28th day – necrotic changes, progressing further at the late stages of the experiment. The loops of Henle undergo sporadic destructive changes at the early stages and at the beginning of the late stage of the experiment. Distal convoluted tubules have been necrotic altered only at the late stages of the experiment

Composition and structure of lamellar composites obtained by intercalation of III-VI layered semiconductor materials

Date du colloque : 05/2013International audienc

Thermoelectric properties of the bismuth telluride nanowires in the constant-relaxation-time approximation

Electronic structure of bismuth telluride nanowires with the growth directions [110] and [015] is studied in the framework of anisotropic effective mass method using the parabolic band approximation. The components of the electron and hole effective mass tensor for six valleys are calculated for both growth directions. For a square nanowire, in the temperature range from 77 K to 500 K, the dependence of the Seebeck coefficient, the electron thermal and electrical conductivity as well as the figure of merit ZT on the nanowire thickness and on the excess hole concentration are investigated in the constant-relaxation-time approximation. The carrier confinement is shown to play essential role for square nanowires with thickness less than 30 nm. The confinement decreases both the carrier concentration and the thermal conductivity but increases the maximum value of Seebeck coefficient in contrast to the excess holes (impurities). The confinement effect is stronger for the direction [015] than for the direction [110] due to the carrier mass difference for these directions. The carrier confinement increases maximum value of ZT and shifts it towards high temperatures. For the p-type bismuth telluride nanowires with growth direction [110], the maximum value of the figure of merit is equal to 1.3, 1.6, and 2.8, correspondingly, at temperatures 310 K, 390 K, 480 K and the nanowire thicknesses 30 nm, 15 nm, and 7 nm. At the room temperature, the figure of merit equals 1.2, 1.3, and 1.7, respectively.Comment: 13 pages, 7 figures, 2 tables, typos added, added references for sections 2-

Outcomes of the 2019 Novel Coronavirus in patients with or without a history of cancer - a multi-centre North London experience

© The Author(s) 2020. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 License (https://creativecommons.org/licenses/by-nc/4.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage).Background Four months after the first known case of the 2019 novel coronavirus disease (COVID-19), on the 11th March 2020, the WHO declared the outbreak a pandemic and acknowledged the potential to overwhelm national healthcare systems. The high prevalence and associated healthcare, social and economic challenges of COVID-19 suggest this pandemic is likely to have a major impact on cancer management, and has been shown to potentially have worse outcomes in this cohort of vulnerable patients (1). This study aims to compare the outcomes of reverse transcriptase polymerase chain reaction (RT-PCR) confirmed COVID-19 positive disease in patients with or without a history of cancer. Method: We retrospectively collected clinical, pathological and radiological characteristics and outcomes of COVID-19 RT-PCR positive cancer patients treated consecutively in four different North London hospitals (cohort A). Outcomes recorded included morbidity, mortality and length of hospital stay. All clinically relevant outcomes were then compared to consecutively admitted COVID-19 positive patients, without a history of cancer (cohort B), treated at the primary centre during the same time period (12th March- 7th April 2020). Results: A total of 52 electronic patient records during the study time period were reviewed. Cohort A (median age 76 years, 56% males) and cohort B (median age 58 years, 62% male) comprised of 26 patients each. With the exclusion of cancer, both had a median of 2 comorbidities. Within cohort A, the most frequent underlying cancer was colorectal (5/26) and prostate cancer (5/26), and 77% of patients in Cohort A had received previous anti-cancer therapy. The most common presenting symptoms were cough and pyrexia in both cohorts. Frequent laboratory findings included lymphopenia, anaemia and elevated CRP in both cohorts, whilst hypokalaemia, hypoalbuminaemia and hypoproteinaemia was predominantly seen amongst patients with cancer. Median duration of admission was 7 days in both cohorts. The mortality rate was the same in both cohorts (23%), with median age of mortality of 80 years. Of cancer patients who died, all were advanced stage, had been treated with palliative intent and had received anti-cancer therapy within 13 days of admission. Conclusion: Old age, late stage of cancer diagnosis and multiple co-morbidities adversely influence the outcome of patients with COVID-19 positive patients. Whilst extra caution is warranted in the administration of anti-cancer therapies pertaining to the risk of immune-suppression, this data does not demonstrate a higher risk to cancer patients compared to their non-cancer counterparts.Peer reviewedFinal Published versio

Some Aspects of Mathematical and Physical Approaches for Topological Quantum Computation

A paradigm to build a quantum computer, based on topological invariants is highlighted. The identities in the ensemble of knots, links and braids originally discovered in relation to topological quantum field theory are shown: how they define Artin braid group -- the mathematical basis of topological quantum computation (TQC). Vector spaces of TQC correspond to associated strings of particle interactions, and TQC operates its calculations on braided strings of special physical quasiparticles -- anyons -- with non-Abelian statistics. The physical platform of TQC is to use the topological quantum numbers of such small groups of anyons as qubits and to perform operations on these qubits by exchanging the anyons, both within the groups that form the qubits and, for multi-qubit gates, between groups. By braiding two or more anyons, they acquire up a topological phase or Berry phase similar to that found in the Aharonov-Bohm effect. Topological matter such as fractional quantum Hall systems and novel discovered topological insulators open the way to form system of anyons -- Majorana fermions -- with the unique property of encoding and processing quantum information in a naturally fault-tolerant way. In the topological insulators, due to its fundamental attribute of topological surface state occurrence of the bound, Majorana fermions are generated at its heterocontact with superconductors. One of the key operations of TQC -- braiding of non-Abelian anyons: it is illustrated how it can be implemented in one-dimensional topological isolator wire networks