Thermodynamics and quantum criticality in cuprate superconductors

We will present elementary scaling arguments focussed on the thermodynamics in the proximity of the quantum critical point in the cuprate superconductors. Extending the analysis centered on the Gr\"uneisen parameter by Rosch, Si and coworkers to the cuprates, we demonstrate that a combination of specific heat- and chemical potential measurements can reveal the nature of the zero temperature singularity. From the known specific heat data it follows that the effective number of time dimensions has to equal the number of space dimensions, while we find a total of six scaling laws governing the temperature and density dependence of the chemical potential, revealing directly the coupling constant scaling dimension.Comment: 4 pages no figure

Optimal configurations for normal-metal traps in transmon qubits

Controlling quasiparticle dynamics can improve the performance of superconducting devices. For example, it has been demonstrated effective in increasing lifetime and stability of superconducting qubits. Here we study how to optimize the placement of normal-metal traps in transmon-type qubits. When the trap size increases beyond a certain characteristic length, the details of the geometry and trap position, and even the number of traps, become important. We discuss for some experimentally relevant examples how to shorten the decay time of the excess quasiparticle density. Moreover, we show that a trap in the vicinity of a Josephson junction can reduce the steady-state quasiparticle density near that junction, thus suppressing the quasiparticle-induced relaxation rate of the qubit. Such a trap also reduces the impact of fluctuations in the generation rate of quasiparticles, rendering the qubit more stable.Comment: 16 pages, 7 figures; to appear in Phys. Rev. Applie

Electromagnetic control of valley splitting in ideal and disordered Si quantum dots

In silicon spin qubits, the valley splitting must be tuned far away from the qubit Zeeman splitting to prevent fast qubit relaxation. In this work, we study in detail how the valley splitting depends on the electric and magnetic fields as well as the quantum dot geometry for both ideal and disordered Si/SiGe interfaces. We theoretically model a realistic electrostatically defined quantum dot and find the exact ground and excited states for the out-of-plane electron motion. This enables us to find the electron envelope function and its dependence on the electric and magnetic fields. For a quantum dot with an ideal interface, the slight cyclotron motion of electrons driven by an in-plane magnetic field slightly increases the valley splitting. Importantly, our modeling makes it possible to analyze the effect of arbitrary configurations of interface disorders. In agreement with previous studies, we show that interface steps can significantly reduce the valley splitting. Interestingly, depending on where the interface steps are located, the magnetic field can increase or further suppress the valley splitting. Moreover, the valley splitting can scale linearly or, in the presence of interface steps, non-linearly with the electric field.Comment: 13+3 pages, 14 figure

The Role of School Health Nurses’ Health Literacy in their Quality of Life in Health-Promoting Schools

Background & Objectives: School Health Nurses in health-promoting schools have a decisive role in the effectiveness of these schools in promoting studentschr('39') health. The main purpose of the present study was to investigate the role of health literacy of health care providers in their quality of life in health-promoting schools of Tabriz education districts. Methods: The present study was a descriptive-analytical one conducted in 175 health-promoting schools in Tabriz in 2019. A total of 120 school health nurses in health-promoting schools of five education districts were selected using stratified random sampling. Data were collected using the Health Literacy Questionnaire of Iranian Institute for Health Sciences Research and the World Health Organizationchr('39')s Quality of Life Questionnaire. Structural equation modeling was used to analyze data through Smart PLS software. Results: The results showed that quality of life with all its dimensions including physical health, emotional health, environmental health and social health are predictable based on all dimensions of health literacy. Conclusion: Improving the health literacy of school health nurses through specialized training courses, conferences, scientific competitions and field visits to successful schools around the world can improve the quality of their lives. Key­words: Health Literacy, Quality of Life, Health Dimensions, Quality of Life Dimensions, Health Care Providers, Health-Promoting Schools Citation: Hosseinkhani N, Talebi B. The Role of School Health Nurses’ Health Literacy in their Quality of Life in Health-Promoting Schools. Journal of Health Based Research 2020; 5(4): 369-82. [In Persian

Differentiation of definitive endoderm from human induced pluripotent stem cells on hMSCs feeder in a defined medium

Background: The Definitive Endoderm (DE) differentiation using the undefined media and non-human feeders can cause contaminations in the generated cells for therapeutic applications. Therefore, generating safer and more appropriate DE cells is needed. This study compared five different methods to establish an appropriate method for inducing an efficient DE differentiation from Human Induced Pluripotent Stem Cells (hiPSCs) on an appropriate feeder in a more defined medium. Methods: Human Induced Pluripotent Stem Cells (hiPSCs) were cultured on inactivated feeders. Passaged hiPSCs, without feeder, were incubated for three days with Activin-A and different endodermal differentiation media including 1-FBS, 2-B27, 3- ITS and albumin fraction-V, 4-B27 and ITS and 5-like the third medium. The feeder cells in the first four methods were Mouse Embryonic Fibroblasts (MEFs) and in the fifth method were human adult bone marrow Mesenchymal Stem Cells (hMSCs). DE markers FOXA2, SOX17 and CXCR4 and also pluripotency marker OCT4 were evaluated using qRT-PCR, as well as FOXA2 by the immunocytochemistry. Results: QRT-PCR analysis showed that after three days, the expression levels of DE and pluripotency markers in the differentiated hiPSCs among all five groups did not have any significant differences. Similarly, the immunocytochemistry analysis demonstrated that the differentiated hiPSCs expressed FOXA2, with no significant differences. Conclusion: Despite this similarity in the results, the third differentiation medium has more defined and cost effective components. Furthermore, hMSC, a human feeder, is safer than MEF. Therefore, the fifth method is preferable among other DE differentiation methods and can serve as a fundamental method helping the development of regenerative medicine. © 2016, Avicenna Journal of Medical Biotechnology. All rights reserved

Apoptosome assay by Split-luciferase constructs

Introduction: Apoptosis is a process of programmed cell death that plays several critical roles in normal biological events happening in multi cellular organisms. Tissue homeostasis, defense against pathogens and involvement in development by controlling the number of cells are some of these critical roles. The two best-described activation mechanisms are the intrinsic (also called the mitochondrial pathway) and the extrinsic pathways. The formation of a supramolecular complex called apoptosome in mammals is tightly linked to ignition of the intrinsic pathway. This complex mainly consists of Apaf-1 molecules (apoptotic factor protease activating 1). The assembled Apaf-1 in apoptosome leads to the formation of functional caspase-9 that it further triggers the caspase cascade, a fundamental cascade that subsequently causes cell death. So detecting the formation of the apoptosome complex will help to screen the drugs and substances inducing intrinsic pathways also it helps in cell death related researches. Methods and Results: we utilized previously developed split luciferase biosensor to investigate apoptosome activity of cells that were treated with Tunicamycin. Tunicamycin is an inhibitor of glycosylation that disturbs protein folding machinery in eukaryotic cells. Tunicamycin causes accumulation of unfolded proteins in cell endoplasmic reticulum (ER) and induces ER stress. ER stress is an essential mechanism for cellular homeostasis which has a role in cell death via reprogramming of protein processing, regulation of autophagy and apoptosis. Therefore, it can trigger apoptosis by induction of protein release such as cytochrome c that stimulates apoptosome formation. The biosensor consists of two separate constructs, N-terminal luciferase-Apaf-1 and C-terminal luciferase-Apaf-1. These constructs are cotransfected into mouse embryonic fibroblasts cells by polyethyleneimine (PEI). When apoptosome complex forms the assembling of Apaf-1 proteins brings the Nlucs and Clubs in spatial proximity that enables the enzyme to catalyst its substrate luciferin and bioluminescence. Split luciferase activity measured in several times after induction by Tunicamycin Conclusions: apoptosome activity has fluctuation mode and we can control this complex activity by pharmacokinetic features of related drugs