620 research outputs found

    Electronic control of the spin-wave damping in a magnetic insulator

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    It is demonstrated that the decay time of spin-wave modes existing in a magnetic insulator can be reduced or enhanced by injecting an in-plane dc current, IdcI_\text{dc}, in an adjacent normal metal with strong spin-orbit interaction. The demonstration rests upon the measurement of the ferromagnetic resonance linewidth as a function of IdcI_\text{dc} in a 5~ΞΌ\mum diameter YIG(20nm){\textbar}Pt(7nm) disk using a magnetic resonance force microscope (MRFM). Complete compensation of the damping of the fundamental mode is obtained for a current density of ∼3β‹…1011A.mβˆ’2\sim 3 \cdot 10^{11}\text{A.m}^{-2}, in agreement with theoretical predictions. At this critical threshold the MRFM detects a small change of static magnetization, a behavior consistent with the onset of an auto-oscillation regime.Comment: 6 pages 4 figure

    A Novel Statistical Algorithm for Gene Expression Analysis Helps Differentiate Pregnane X Receptor-Dependent and Independent Mechanisms of Toxicity

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    Genome-wide gene expression profiling has become standard for assessing potential liabilities as well as for elucidating mechanisms of toxicity of drug candidates under development. Analysis of microarray data is often challenging due to the lack of a statistical model that is amenable to biological variation in a small number of samples. Here we present a novel non-parametric algorithm that requires minimal assumptions about the data distribution. Our method for determining differential expression consists of two steps: 1) We apply a nominal threshold on fold change and platform p-value to designate whether a gene is differentially expressed in each treated and control sample relative to the averaged control pool, and 2) We compared the number of samples satisfying criteria in step 1 between the treated and control groups to estimate the statistical significance based on a null distribution established by sample permutations. The method captures group effect without being too sensitive to anomalies as it allows tolerance for potential non-responders in the treatment group and outliers in the control group. Performance and results of this method were compared with the Significant Analysis of Microarrays (SAM) method. These two methods were applied to investigate hepatic transcriptional responses of wild-type (PXR+/+) and pregnane X receptor-knockout (PXRβˆ’/βˆ’) mice after 96 h exposure to CMP013, an inhibitor of Ξ²-secretase (Ξ²-site of amyloid precursor protein cleaving enzyme 1 or BACE1). Our results showed that CMP013 led to transcriptional changes in hallmark PXR-regulated genes and induced a cascade of gene expression changes that explained the hepatomegaly observed only in PXR+/+ animals. Comparison of concordant expression changes between PXR+/+ and PXRβˆ’/βˆ’ mice also suggested a PXR-independent association between CMP013 and perturbations to cellular stress, lipid metabolism, and biliary transport

    Feedback control architecture and the bacterial chemotaxis network.

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    PMCID: PMC3088647This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Bacteria move towards favourable and away from toxic environments by changing their swimming pattern. This response is regulated by the chemotaxis signalling pathway, which has an important feature: it uses feedback to 'reset' (adapt) the bacterial sensing ability, which allows the bacteria to sense a range of background environmental changes. The role of this feedback has been studied extensively in the simple chemotaxis pathway of Escherichia coli. However it has been recently found that the majority of bacteria have multiple chemotaxis homologues of the E. coli proteins, resulting in more complex pathways. In this paper we investigate the configuration and role of feedback in Rhodobacter sphaeroides, a bacterium containing multiple homologues of the chemotaxis proteins found in E. coli. Multiple proteins could produce different possible feedback configurations, each having different chemotactic performance qualities and levels of robustness to variations and uncertainties in biological parameters and to intracellular noise. We develop four models corresponding to different feedback configurations. Using a series of carefully designed experiments we discriminate between these models and invalidate three of them. When these models are examined in terms of robustness to noise and parametric uncertainties, we find that the non-invalidated model is superior to the others. Moreover, it has a 'cascade control' feedback architecture which is used extensively in engineering to improve system performance, including robustness. Given that the majority of bacteria are known to have multiple chemotaxis pathways, in this paper we show that some feedback architectures allow them to have better performance than others. In particular, cascade control may be an important feature in achieving robust functionality in more complex signalling pathways and in improving their performance

    Π˜ΠΌΠΌΠΎΠ±ΠΈΠ»ΠΈΠ·Π°Ρ†ΠΈΡ РАО Π² ΠΏΠ΅Ρ€ΠΎΠ²ΡΠΊΠΈΡ‚ΠΎΠΏΠΎΠ΄ΠΎΠ±Π½ΡƒΡŽ ΠΌΠ°Ρ‚Ρ€ΠΈΡ†Ρƒ

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    Выпускная квалификационная Ρ€Π°Π±ΠΎΡ‚Π° с., рис., Ρ‚Π°Π±Π»., источников, ΠΏΡ€ΠΈΠ». ΠšΠ»ΡŽΡ‡Π΅Π²Ρ‹Π΅ слова: пСровскит, иммобилизация Ρ€Π°Π΄ΠΈΠΎΠ°ΠΊΡ‚ΠΈΠ²Π½Ρ‹Ρ… ΠΎΡ‚Ρ…ΠΎΠ΄ΠΎΠ², ΡΠ°ΠΌΠΎΡ€Π°ΡΠΏΡ€ΠΎΡΡ‚Ρ€Π°Π½ΡΡŽΡ‰ΠΈΠΉΡΡ высокотСмпСратурный синтСз, ΠΌΠ°Ρ‚Ρ€ΠΈΡ‡Π½Ρ‹Π΅ ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»Ρ‹ ΠžΠ±ΡŠΠ΅ΠΊΡ‚ΠΎΠΌ исслСдования являСтся иммобилизация Ρ€Π°Π΄ΠΈΠΎΠ°ΠΊΡ‚ΠΈΠ²Π½Ρ‹Ρ… ΠΎΡ‚Ρ…ΠΎΠ΄ΠΎΠ² Π² ΠΌΠ°Ρ‚Ρ€ΠΈΡ‡Π½Ρ‹ΠΉ ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π» ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ Π‘Π’Π‘ Π½Π° основС пСровскита. ЦСль Ρ€Π°Π±ΠΎΡ‚Ρ‹ – ΠΏΠΎΠ»ΡƒΡ‡Π΅Π½ΠΈΠ΅ химичСски устойчивой ΠΌΠ°Ρ‚Ρ€ΠΈΡ†Ρ‹ для ΠΈΠΌΠΌΠΎΠ±ΠΈΠ»ΠΈΠ·Π°Ρ†ΠΈΠΈ Π°ΠΊΡ‚ΠΈΠ½ΠΎΠΈΠ΄Π½ΠΎΠΉ Ρ„Ρ€Π°ΠΊΡ†ΠΈΠΈ Ρ€Π°Π΄ΠΈΠΎΠ°ΠΊΡ‚ΠΈΠ²Π½Ρ‹Ρ… ΠΎΡ‚Ρ…ΠΎΠ΄ΠΎΠ² ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ Π‘Π’Π‘ Π’ процСссС выполнСния магистСрской диссСртации ΠΎΡ‚Ρ€Π°Π±ΠΎΡ‚Π°Π½Π° тСхнология получСния ΠΌΠ°Ρ‚Ρ€ΠΈΡ‡Π½ΠΎΠ³ΠΎ ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»Π° ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ Π‘Π’Π‘. Π’ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Π΅ исслСдования Π±Ρ‹Π»ΠΈ ΠΎΠΏΡ€Π΅Π΄Π΅Π»Π΅Π½Ρ‹ закономСрности образования Ρ„Π°Π· состава ΠΌΠ°Ρ‚Ρ€ΠΈΡ†. Π‘Ρ‚Π΅ΠΏΠ΅Π½ΡŒ внСдрСния: организация тСхнологичСского процСсса ΠΈΠΌΠΌΠΎΠ±ΠΈΠ»ΠΈΠ·Π°Ρ†ΠΈΠΈ Π°ΠΊΡ‚ΠΈΠ½ΠΎΠΈΠ΄Π½ΠΎΠΉ Ρ„Ρ€Π°ΠΊΡ†ΠΈΠΈ Ρ€Π°Π΄ΠΈΠΎΠ°ΠΊΡ‚ΠΈΠ²Π½Ρ‹Ρ… ΠΎΡ‚Ρ…ΠΎΠ΄ΠΎΠ² ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ Π‘Π’Π‘ ΠžΠ±Π»Π°ΡΡ‚ΡŒ примСнСния: Π°Ρ‚Final qualifying work with., Fig., Tab., Sources, adj. Keywords: perovskite, radioactive waste immobilization, self-propagating high-temperature synthesis, matrix materials The object of research is the immobilization of radioactive waste in the matrix material by the SHS-based perovskite. The purpose of work - to obtain a chemically stable matrix for the immobilization of actinide fraction of radioactive waste by SHS In carrying out the master's thesis the technology of producing the matrix material by SHS. The study of the formation of the composition of the matrix phase have been identified. Degree of implementation: the organization of the process of immobilization actinide fraction of radioactive waste by SHS Scope: the nuclear industry

    Severe steroid-related neuropsychiatric symptoms during paediatric acute lymphoblastic leukaemia therapyβ€”An observational Ponte di Legno Toxicity Working Group Study

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    \ua9 2024 The Author(s). British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.Steroids are a mainstay in the treatment of acute lymphoblastic leukaemia (ALL) in children and adolescents; however, their use can cause clinically significant steroid-related neuropsychiatric symptoms (SRNS). As current knowledge on SRNS during ALL treatment is limited, we mapped the phenotypes, occurrence and treatment strategies using a database created by the international Ponte di Legno Neurotoxicity Working Group including data on toxicity in the central nervous system (CNS) in patients treated with frontline ALL protocols between 2000 and 2017. Ninety-four of 1813 patients in the CNS toxicity database (5.2%) experienced clinically significant SRNS with two peaks: one during induction and one during intensification phase. Dexamethasone was implicated in 86% of SRNS episodes. The most common symptoms were psychosis (52%), agitation (44%) and aggression (31%). Pharmacological treatment, mainly antipsychotics and benzodiazepines, was given to 87% of patients while 38% were hospitalised due to their symptoms. Recurrence of symptoms was reported in 29% of patients and two previously healthy patients required ongoing pharmacological treatment at the last follow up. Awareness of SRNS during ALL treatment and recommendation on treatment strategies merit further studies and consensus

    Outcomes of patients with childhood B-cell precursor acute lymphoblastic leukaemia with late bone marrow relapses: long-term follow-up of the ALLR3 open-label randomised trial

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    Background: The ALLR3 trial investigated outcomes of children with B-cell precursor acute lymphoblastic leukaemia who had late bone marrow relapses. We analysed long-term follow-up outcomes of these patients. Methods: ALLR3 was an open-label randomised clinical trial that recruited children aged 1-18 years with B-cell precursor acute lymphoblastic leukaemia who had late bone marrow relapses. Eligible patients were recruited from centres in Australia, Ireland, the Netherlands, New Zealand, and the UK. Patients were randomly assigned from Jan 31, 2003, to Dec 31, 2007, and the trial closed to recruitment on Oct 31, 2013. Randomly assigned patients were allocated to receive either idarubicin or mitoxantrone in induction by stratified concealed randomisation; after randomisation stopped in Dec 31, 2007, all patients were allocated to receive mitoxantrone. After three blocks of therapy, patients with high minimal residual disease (β‰₯10-4 cells) at the end of induction were allocated to undergo allogeneic stem-cell transplantation and those with low minimal residual disease (<10-4 cells) at the end of induction were allocated to receive chemotherapy. Minimal residual disease level was measured by real-time quantitative PCR analysis of immunoglobulin and T-cell receptor gene rearrangements. The primary endpoint of the original ALLR3 clinical trial was progression-free survival of randomly assigned patients. The primary endpoint of this long-term follow-up analysis was progression-free survival of patients with late bone marrow relapses stratified by minimal residual disease level. Outcomes were correlated with age, site, time to recurrence, and genetic subtypes, and analysed by both intention to treat and actual treatment received. This trial is registered on the ISRCTN registry, number ISRCTN45724312, and on ClinicalTrials.gov, number NCT00967057. Findings: Between Feb 2, 2003, and Oct 28, 2013, 228 patients with B-cell precursor acute lymphoblastic leukaemia and late bone marrow relapses were treated. After a median follow-up of 84 months (IQR 48-109), progression-free survival of all randomly assigned patients was 60% (95% CI 54-70). 220 patients achieved second complete remission, and minimal residual disease was evaluable in 192 (87%). 110 patients with late bone marrow relapses and high minimal residual disease at the end of induction were allocated to undergo stem-cell transplantation, and 82 patients with low minimal residual disease at the end of induction were allocated to receive chemotherapy. In the patients allocated to undergo stem-cell transplantation, four relapses and three deaths were reported before the procedure, and 11 patients were not transplanted. Of the 92 patients transplanted, 58 (63%) remained in second complete remission, 13 (14%) died of complications, and 21 (23%) relapsed after stem-cell transplantation. In patients allocated to receive chemotherapy, one early treatment-related death was reported and 11 patients were transplanted. Of the 70 patients who continued on chemotherapy, 49 (70%) remained in second complete remission, two (3%) died of complications, and 19 (27%) relapsed. Progression-free survival at 5 years was 56% (95% CI 46-65) in those with high minimal residual disease and 72% (60-81) in patients with low minimal residual disease (p=0Β·0078). Treatment-related serious adverse events were not analysed in the long-term follow-up. Iinterpretation: Patients with B-cell precursor acute lymphoblastic leukaemia with late bone marrow relapses and low minimal residual disease at end of induction had favourable outcomes with chemotherapy without undergoing stem-cell transplantation. Patients with high minimal residual disease benefited from stem-cell transplantation, and targeted therapies might offer further improvements in outcomes for these patients.Catriona Parker, Shekhar Krishnan, Lina Hamadeh, Julie AE Irving, Roland P Kuiper, Tamas RΓ©vΓ©sz, Peter Hoogerbrugge, Jeremy Hancock, Rosemary Sutton, Anthony V Moorman, Vaskar Sah

    Π Π°Π·Ρ€Π°Π±ΠΎΡ‚ΠΊΠ° Π½ΠΎΠ²Ρ‹Ρ… Π²ΠΈΠ΄ΠΎΠ² сорбционных ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π»ΠΎΠ² Π½Π° ΠΌΠΈΠ½Π΅Ρ€Π°Π»ΡŒΠ½ΠΎΠΉ основС для извлСчСния тяТСлых ΠΌΠ΅Ρ‚Π°Π»Π»ΠΎΠ² ΠΈΠ· Π²ΠΎΠ΄Π½Ρ‹Ρ… срСд

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    Π’ процСссС исслСдования ΠΏΡ€ΠΎΠ²ΠΎΠ΄ΠΈΠ»ΠΎΡΡŒ ΠΈΠ·ΡƒΡ‡Π΅Π½ΠΈΠ΅ Π»ΠΈΡ‚Π΅Ρ€Π°Ρ‚ΡƒΡ€Π½Ρ‹Ρ… источников.Π’ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Π΅ Π±Ρ‹Π» Ρ€Π°Π·Ρ€Π°Π±ΠΎΡ‚Π°Π½ Π½ΠΎΠ²Ρ‹ΠΉ сорбционный ΠΌΠ°Ρ‚Π΅Ρ€ΠΈΠ°Π» Π½Π° ΠΌΠΈΠ½Π΅Ρ€Π°Π»ΡŒΠ½ΠΎΠΉ основС для извлСчСния Ρ‚ΠΈΠΎΠ½ΠΎΠ² кадмия ΠΈ свинца ΠΈΠ· Π²ΠΎΠ΄Π½Ρ‹Ρ… растворов.In the process of investigation the study of literary sources.In the result there was developed a new sorption material on a mineral basis for izvlecheniya thions of cadmium and lead from aqueous plaster
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