Subgap anomaly and above-energy-gap structure in chains of diffusive SNS junctions

We present the results of low-temperature transport measurements on chains of superconductor--normal-constriction--superconductor (SNS) junctions fabricated on the basis of superconducting PtSi film. A comparative study of the properties of the chains, consisting of 3 and 20 SNS junctions in series, and single SNS junctions reveals essential distinctions in the behavior of the current-voltage characteristics of the systems: (i) the gradual decrease of the effective suppression voltage for the excess conductivity observed at zero bias as the quantity of the SNS junctions increases, (ii) a rich fine structure on the dependences dV/dI-V at dc bias voltages higher than the superconducting gap and corresponding to some multiples of 2\Delta/e. A model to explain this above-energy-gap structure based on energy relaxation of electron via Cooper-pair-breaking in superconducting island connecting normal metal electrods is proposed.Comment: RevTex, 5 pages, 4 figure

Superconductivity on the localization threshold and magnetic-field-tuned superconductor-insulator transition in TiN films

Temperature- and magnetic-field dependent measurements of the resistance of ultrathin superconducting TiN films are presented. The analysis of the temperature dependence of the zero field resistance indicates an underlying insulating behavior, when the contribution of Aslamasov-Larkin fluctuations is taken into account. This demonstrates the possibility of coexistence of the superconducting and insulating phases and of a direct transition from the one to the other. The scaling behavior of magnetic field data is in accordance with a superconductor-insulator transition (SIT) driven by quantum phase fluctuations in two-dimensional superconductor. The temperature dependence of the isomagnetic resistance data on the high-field side of the SIT has been analyzed and the presence of an insulating phase was confirmed. A transition from the insulating to a metallic phase is found at high magnetic fields, where the zero-temperature asymptotic value of the resistance being equal to h/e^2.Comment: 5 pages, 4 eps figures, RevTeX4, Published versio

The global retinoblastoma outcome study : a prospective, cluster-based analysis of 4064 patients from 149 countries

DATA SHARING : The study data will become available online once all analyses are complete.BACKGROUND : Retinoblastoma is the most common intraocular cancer worldwide. There is some evidence to suggest that major differences exist in treatment outcomes for children with retinoblastoma from different regions, but these differences have not been assessed on a global scale. We aimed to report 3-year outcomes for children with retinoblastoma globally and to investigate factors associated with survival. METHODS : We did a prospective cluster-based analysis of treatment-naive patients with retinoblastoma who were diagnosed between Jan 1, 2017, and Dec 31, 2017, then treated and followed up for 3 years. Patients were recruited from 260 specialised treatment centres worldwide. Data were obtained from participating centres on primary and additional treatments, duration of follow-up, metastasis, eye globe salvage, and survival outcome. We analysed time to death and time to enucleation with Cox regression models. FINDINGS : The cohort included 4064 children from 149 countries. The median age at diagnosis was 23·2 months (IQR 11·0–36·5). Extraocular tumour spread (cT4 of the cTNMH classification) at diagnosis was reported in five (0·8%) of 636 children from high-income countries, 55 (5·4%) of 1027 children from upper-middle-income countries, 342 (19·7%) of 1738 children from lower-middle-income countries, and 196 (42·9%) of 457 children from low-income countries. Enucleation surgery was available for all children and intravenous chemotherapy was available for 4014 (98·8%) of 4064 children. The 3-year survival rate was 99·5% (95% CI 98·8–100·0) for children from high-income countries, 91·2% (89·5–93·0) for children from upper-middle-income countries, 80·3% (78·3–82·3) for children from lower-middle-income countries, and 57·3% (52·1-63·0) for children from low-income countries. On analysis, independent factors for worse survival were residence in low-income countries compared to high-income countries (hazard ratio 16·67; 95% CI 4·76–50·00), cT4 advanced tumour compared to cT1 (8·98; 4·44–18·18), and older age at diagnosis in children up to 3 years (1·38 per year; 1·23–1·56). For children aged 3–7 years, the mortality risk decreased slightly (p=0·0104 for the change in slope). INTERPRETATION : This study, estimated to include approximately half of all new retinoblastoma cases worldwide in 2017, shows profound inequity in survival of children depending on the national income level of their country of residence. In high-income countries, death from retinoblastoma is rare, whereas in low-income countries estimated 3-year survival is just over 50%. Although essential treatments are available in nearly all countries, early diagnosis and treatment in low-income countries are key to improving survival outcomes.The Queen Elizabeth Diamond Jubilee Trust and the Wellcome Trust.https://www.thelancet.com/journals/langlo/homeam2023Paediatrics and Child Healt

Синтез нелінійної системи керування з невідомим вектором станів

In this article, the problem of development of nonlinear state observer for an object defined by a system of nonlinear differential equations of a certain kind has been solved.Obtained observer restores full information on the state variables of the control object. As a result of experimental research, guidelines for choosing the feedback coefficients of the observer have been proposed.On the basis of obtained observer, synthesis of nonlinear control system using the controller based on the backstepping method has been made.To verify the analytical expressions, models of control systems using the software package Matlab/Simulink have been developed.Reference 1, figures 8.В данной статье решается задача разработки нелинейного наблюдающего устройства для объекта, заданного системой нелинейных дифференциальных уравнений определенного вида.Разработанное наблюдающее устройство восстанавливает полную информацию о переменных состояния объекта управления. В результате экспериментальных исследований были предложены рекомендации для выбора коэффициентов обратной связи наблюдающего устройства.На базе полученного наблюдающего устройства выполнен синтез нелинейной системы управления с помощью регулятора на основе метода «backstepping».Для проверки аналитических выражений разработаны модели систем управления с помощью программного пакета Matlab/Simulink.Библ.1, рис.8.У даній статті вирішується задача розробки нелінійного спостерігаючого пристрою для об'єкта, заданого системою нелінійних диференціальних рівнянь певного виду.Розроблений спостерігаючий пристрій відновлює повну інформацію про змінні стану об'єкта управління. В результаті експериментальних досліджень були запропоновані рекомендації для вибору коефіцієнтів зворотного зв'язку спостерігаючого пристрою.На базі отриманого спостерігаючого пристрою виконується синтез нелінійної системи управління за допомогою регулятора на основі методу  «backstepping».Для перевірки аналітичних виразів розроблені моделі систем управління за допомогою програмного пакету Matlab/Simulink.Бібл.1, рис.

Structure of copper(II) complexes grown from ionic liquids – 1-ethyl-3-methylimidazolium acetate or chloride

Crystals of four new copper(II) complexes have been grown from copper(II) acetate/chloride–1-ethyl-3-methylimidazolium acetate/chloride–water systems and characterized by X-ray analysis. The first complex, bis(1-ethyl-3-methylimidazolium) tetra-μ-acetato-bis[chloridocuprate(II)], [Emim]2[Cu2(C2H3O2)4Cl2] (1) (Emim is 1-ethyl-3-methylimidazolium, C6H11N2), contains [Cu2(C2H3O2)4Cl2]2− coordination anions with a paddle-wheel structure and ionic liquid cations. Two of the synthesized complexes are one-dimensional polymers, namely catena-poly[1-ethyl-3-methylimidazolium [[tetra-μ-acetato-dicuprate(II)]-μ-chlorido] monohydrate], {[Emim][Cu2(C2H3O2)4Cl]·H2O}n (2), and catena-poly[1-ethyl-3-methylimidazolium [[tetra-μ-acetato-dicuprate(II)]-μ-acetato]], {[Emim][Cu2(C2H3O2)5]}n (3). In these compounds, the Cu2(C2H3O2)4 units with a paddle-wheel structure are connected to each other through chloride (in 2) or acetate (in 3) anions to form parallel chains, between which cations of ionic liquid are situated. The last compound, bis(1-ethyl-3-methylimidazolium) tetra-μ-acetato-bis[aquacopper(II)] tetra-μ-acetato-bis[acetatocuprate(II)] dihydrate, [Emim]2[Cu2(C2H3O2)4(H2O)2][Cu2(C2H3O2)6]·2H2O (4), contains two different binuclear coordination units (neutral and anionic), connected through hydrogen bonds between water molecules and acetate ions

Synthesis of nonlinear control systems with an unknown state vector

У даній статті вирішується задача розробки нелінійного спостерігаючого пристрою для об'єкта, заданого системою нелінійних диференціальних рівнянь певного виду. Розроблений спостерігаючий пристрій відновлює повну інформацію про змінні стану об'єкта управління. В результаті експериментальних досліджень були запропоновані рекомендації для вибору коефіцієнтів зворотного зв'язку спостерігаючого пристрою. На базі отриманого спостерігаючого пристрою виконується синтез нелінійної системи управління за допомогою регулятора на основі методу «backstepping». Для перевірки аналітичних виразів розроблені моделі систем управління за допомогою програмного пакету Matlab/Simulink.In this article, the problem of development of nonlinear state observer for an object defined by a system of nonlinear differential equations of a certain kind has been solved. Obtained observer restores full information on the state variables of the control object. As a result of experimental research, guidelines for choosing the feedback coefficients of the observer have been proposed. On the basis of obtained observer, synthesis of nonlinear control system using the controller based on the backstepping method has been made. To verify the analytical expressions, models of control systems using the software package Matlab/Simulink have been developed.В данной статье решается задача разработки нелинейного наблюдающего устройства для объекта, заданного системой нелинейных дифференциальных уравнений определенного вида. Разработанное наблюдающее устройство восстанавливает полную информацию о переменных состояния объекта управления. В результате экспериментальных исследований были предложены рекомендации для выбора коэффициентов обратной связи наблюдающего устройства. На базе полученного наблюдающего устройства выполнен синтез нелинейной системы управления с помощью регулятора на основе метода «backstepping». Для проверки аналитических выражений разработаны модели систем управления с помощью программного пакета Matlab/Simulink

EFFECT OF TRACE ELEMENT STATUS ON ATOPIC DERMATITIS

Atopic dermatitis (AD, atopic eczema, atopic eczema / dermatitis syndrome) is a chronic inflammatory skin disease that usually begins in early childhood and may continue or recur into adulthood.The study of atopic dermatitis remains one of the most pressing problems of modern dermatology in connection with the widespread, severe course, frequent relapses, the disease of the most children. According to statistics, it occupies one of the first places in children for reasons of patients' referral to the polyclinic dermatological profile, it is caused by 30-40% of all skin diseases and 30-40% of cases of hospitalization in a dermatological hospital. The disease occurs in both sexes and in different age groups. The incidence ranges from 6.0% to 15.0%