Holographic Thermal Relaxation in Superfluid Turbulence

Holographic duality provides a first-principles approach to investigate real time processes in quantum many-body systems, in particular at finite temperature and far-from-equilibrium. We use this approach to study the dynamical evolution of vortex number in a two-dimensional (2D) turbulent superfluid through numerically solving its gravity dual. We find that the temporal evolution of the vortex number can be well fit statistically by two-body decay due to the vortex pair annihilation featured relaxation process, thus confirm the previous suspicion based on the experimental data for turbulent superfluid in highly oblate Bose-Einstein condensates. Furthermore, the decay rate near the critical temperature is in good agreement with the recently developed effective theory of 2D superfluid turbulence.Comment: 14 pages, version to appear in JHEP. Movies available at http://people.ucas.ac.cn/~ytian?language=en#17155

Sex Differences in Primary and Secondary Prevention of Cardiovascular Disease in China

Background: Despite improvements in diagnostic and therapeutic interventions to combat cardiovascular disease (CVD) in recent decades, there are significant ongoing access gaps and sex disparities in prevention that have not been adequately quantified in China. Methods: A representative, cross-sectional, community-based survey of adults (aged ≥45 years) was conducted in 7 geographic regions of China between 2014 and 2016. Logistic regression models were used to determine sex differences in primary and secondary CVD prevention, and any interaction by age, education level, and area of residence. Data are presented as adjusted odds ratios (ORs) and 95% CIs. Results: Of 47 841 participants (61.3% women), 5454 (57.2% women) had established CVD and 9532 (70.5% women) had a high estimated 10-year CVD risk (≥10%). Only 48.5% and 48.6% of women and 39.3% and 59.8% of men were on any kind of blood pressure (BP)-lowering medication, lipid-lowering medication, or antiplatelet therapy for primary and secondary prevention, respectively. Women with established CVD were significantly less likely than men to receive BP-lowering medications (OR, 0.79 [95% CI, 0.65-0.95]), lipid-lowering medications (OR, 0.69 [95% CI, 0.56-0.84]), antiplatelets (OR, 0.53 [95% CI, 0.45-0.62]), or any CVD prevention medication (OR, 0.62 [95% CI, 0.52-0.73]). Women with established CVD, however, had better BP control (OR, 1.31 [95% CI, 1.14-1.50]) but less well-controlled low-density lipoprotein cholesterol (OR, 0.66 [95% CI, 0.57-0.76]), and were less likely to smoke (OR, 13.89 [95% CI, 11.24-17.15]) and achieve physical activity targets (OR, 1.92 [95% CI, 1.61-2.29]). Conversely, women with high CVD risk were less likely than men to have their BP, low-density lipoprotein cholesterol, and bodyweight controlled (OR, 0.46 [95% CI, 0.38-0.55]; OR, 0.60 [95% CI, 0.52-0.69]; OR, 0.55 [95% CI, 0.48-0.63], respectively), despite a higher use of BP-lowering medications (OR, 1.21 [95% CI, 1.01-1.45]). Younger patients (<65 years) with established CVD were less likely to be taking CVD preventive medications, but there were no sex differences by area of residence or education level. Conclusions: Large and variable gaps in primary and secondary CVD prevention exist in China, particularly for women. Effective CVD prevention requires an improved overall nationwide strategy and a special emphasis on women with established CVD, who have the greatest disparity and the most to benefit

Dedifferentiation and Proliferation of Mammalian Cardiomyocytes

It has long been thought that mammalian cardiomyocytes are terminally-differentiated and unable to proliferate. However, myocytes in more primitive animals such as zebrafish are able to dedifferentiate and proliferate to regenerate amputated cardiac muscle.Here we test the hypothesis that mature mammalian cardiomyocytes retain substantial cellular plasticity, including the ability to dedifferentiate, proliferate, and acquire progenitor cell phenotypes. Two complementary methods were used: 1) cardiomyocyte purification from rat hearts, and 2) genetic fate mapping in cardiac explants from bi-transgenic mice. Cardiomyocytes isolated from rodent hearts were purified by multiple centrifugation and Percoll gradient separation steps, and the purity verified by immunostaining and RT-PCR. Within days in culture, purified cardiomyocytes lost their characteristic electrophysiological properties and striations, flattened and began to divide, as confirmed by proliferation markers and BrdU incorporation. Many dedifferentiated cardiomyocytes went on to express the stem cell antigen c-kit, and the early cardiac transcription factors GATA4 and Nkx2.5. Underlying these changes, inhibitory cell cycle molecules were suppressed in myocyte-derived cells (MDCs), while microRNAs known to orchestrate proliferation and pluripotency increased dramatically. Some, but not all, MDCs self-organized into spheres and re-differentiated into myocytes and endothelial cells in vitro. Cell fate tracking of cardiomyocytes from 4-OH-Tamoxifen-treated double-transgenic MerCreMer/ZEG mouse hearts revealed that green fluorescent protein (GFP) continues to be expressed in dedifferentiated cardiomyocytes, two-thirds of which were also c-kit(+).Contradicting the prevailing view that they are terminally-differentiated, postnatal mammalian cardiomyocytes are instead capable of substantial plasticity. Dedifferentiation of myocytes facilitates proliferation and confers a degree of stemness, including the expression of c-kit and the capacity for multipotency

Eich-Gravitations-Dualität in gravitationell rückgewirkten Hintergründen

The topic of this thesis is generalizations of the Anti de Sitter/Conformal Field Theory (AdS/CFT) correspondence, often referred to as holography, and their application to models relevant for condensed matter physics. A particular virtue of AdS/CFT is to map strongly coupled quantum field theories, for which calculations are inherently difficult, to more tractable classical gravity theories. I use this approach to study the crossover between Bose-Einstein condensation (BEC) and the Bardeen-Cooper-Schrieffer (BCS) superconductivity mechanism. I also study the phase transitions between the AdS black hole and AdS soliton spacetime in the presence of disorder. Moreover, I consider a holographic model of a spin impurity interacting with a strongly correlated electron gas, similar to the Kondo model. In AdS/CFT, the BEC/BCS crossover is modeled by a soliton configuration in the dual geometry and we study the BEC and BCS limits. The backreaction of the matter field on the background geometry is considered, which provides a new approach to study the BEC/BCS crossover. The behaviors of some physical quantities such as depletion of charge density under different strength of backreaction are presented and discussed. Moreover, the backreaction enables us to obtain the effective energy density of the soliton configurations, which together with the surface tension of the solitons leads to an argument for the occurrence of so called snake instability for dark solitons, i.e. for the solitons to form a vortex-like structures. Disordering strongly coupled and correlated quantum states of matter may lead to new insights into the physics of many body localized (MBL) strongly correlated states, which may occur in the presence of strong disorder. We are interested in potential insulator-metal transitions induced by disorder, and how disorder affects the Hawking-Page phase transition in AdS gravity in general. We introduce a metric ansatz and numerically construct the corresponding disordered AdS soliton and AdS black hole solutions, and discuss the calculation of the free energy in these states. In the Kondo effect, the rise in resistivity in metals with scarce magnetic impurities at low temperatures can be explained by the RG flow of the antiferromagnetic coupling between the impurity and conduction electrons in CFT. The generalizations to SU(N) in the large N limit make the treatment amenable to the holographic approach. We add a Maxwell term to a previously existing holographic model to study the conductivity of the itinerant electrons. Our goal is to find the log(T) behavior in the DC resistivity. In the probe limit, we introduce junction conditions to connect fields crossing the defect. We then consider backreactions, which give us a new metric ansatz and new junction conditions for the gauge fields.Das Thema dieser Arbeit sind Verallgemeinerungen der Anti-de-Sitter/Conformal Field Theory Korrespondenz (AdS/CFT-Korrespondenz), die oft auch als Holographie bezeichnet wird, und deren Anwendung auf Modelle, die für die Physik der kondensierten Materie relevant sind. Ein besonderer Vorteil von AdS / CFT ist die Abbildung stark gekoppelter Quantenfeldtheorien, für die Berechnungen insbesondere in fermionischen Systemen von Natur aus schwierig sind, auf leichter zu fassende klassische Gravitationstheorien. Mit diesem Zugang untersuche ich den Übergang zwischen der Bose-Einstein-Kondensation (BEC) und dem Supraleitungsmechanismus nach Bardeen- Cooper-Schrieffer (BCS). Ich untersuche auch die Phasenübergänge zwischen dem schwarzen Loch in der Anti de Sitter Raumzeit und der AdS - Solitonenraumzeit in der Vorhandensein von Unordnung. Außerdem betrachte ich ein holographisches Modell ähnlich dem Kondo-Modell, welches eine Spin-Störstelle, die mit einem stark korrelierten Elektronengas interagiert, beschreibt. In AdS / CFT wird der BEC/BCS-Übergang durch eine Solitonenkonfiguration in der dualen Geometrie modelliert, und wir untersuchen die asymptotischen BEC- und BCS-Grenzfälle. Die Rückwirkung des Materiefelds auf die Hintergrundgeometrie wird berücksichtigt, was eine neue Richtung zur Untersuchung des holographischen BEC / BCS-Übergangs eröffnet. Das Verhalten einiger physikalischer Größen wie z.B. der Ladungsdichte bei unterschiedlicher Stärke der Rückwirkung werden vorgestellt und diskutiert. Die Rückwirkung ermöglicht es uns außerdem, die effektive Energiedichte der Solitonen-Konfigurationen zu bestimmen, was zusammen mit der Oberflächenspannung der Solitonen zu einem Argument für das Auftreten einer sogenannten Schlangeninstabilität für dunkle Solitonen führt, d. h. für die Solitonen, die wirbel-ähnliche Strukturen bilden. Die Unordnung stark gekoppelter und korrelierter Quantenzustände der Materie kann zu neuen Erkenntnissen über die Physik vielteilchenlokalisierter stark korrelierter Zustände führen, die im Grenzfall starker Unordnung auftreten können. Ich untersuche mögliche Isolator-Metall-Übergänge, die durch die Unordnung induziert werden, sowie die Auswirkung von Unordnung auf den Hawking-Page-Phasenübergang in der AdS-Raumzeit im Allgemeinen. Wir führen einen metrischen Ansatz ein und konstruieren numerisch die entsprechenden ungeordneten AdS-Solitonen- und AdS-Schwarzloch-Lösungen, und diskutieren die Berechnung der freien Energie in diesen Zuständen. Der Anstieg des spezifischen Widerstands in Metallen mit vereinzelten magnetischen Verunreinigungen bei niedrigen Temperaturen lässt sich mit dem RG-Fluss der antiferromagnetischen Kopplung zwischen den Verunreinigungs- und Leitungselektronen erklären. Die Verallgemeinerungen zu SU(N)-Spins in Limes großer N machen die Behandlung durch den holographischen Zugang möglich. Wir fügen einem zuvor existierenden holographischen Modell einen Maxwell-Term hinzu, um die Leitfähigkeit der Leitungselektronen zu untersuchen. Unser Ziel ist es, das logT-Verhalten im Gleichstromwiderstand zu finden. Im Limes verschwindender Rückwirkung auf die Hintergrundgeometrie führen wir Übergangsbedingungen ein, um die gravitationellen Felder über dem Defekt, welcher holographisch die magnetische Verunreinigung beschreibt, zu verbinden. Dann betrachten wir die Rückwirkung auf die Geometrie, die uns einen neuen metrischen Ansatz und neue Übergangsbedingungen für die Eichfelder gibt

Gauge/Gravity Duality with Backreacting Background

The topic of this thesis is generalizations of the Anti de Sitter/Conformal Field Theory (AdS/CFT) correspondence, often referred to as holography, and their application to models relevant for condensed matter physics. A particular virtue of AdS/CFT is to map strongly coupled quantum field theories, for which calculations are inherently difficult, to more tractable classical gravity theories. I use this approach to study the crossover between Bose-Einstein condensation (BEC) and the Bardeen-Cooper-Schrieffer (BCS) superconductivity mechanism. I also study the phase transitions between the AdS black hole and AdS soliton spacetime in the presence of disorder. Moreover, I consider a holographic model of a spin impurity interacting with a strongly correlated electron gas, similar to the Kondo model. In AdS/CFT, the BEC/BCS crossover is modeled by a soliton configuration in the dual geometry and we study the BEC and BCS limits. The backreaction of the matter field on the background geometry is considered, which provides a new approach to study the BEC/BCS crossover. The behaviors of some physical quantities such as depletion of charge density under different strength of backreaction are presented and discussed. Moreover, the backreaction enables us to obtain the effective energy density of the soliton configurations, which together with the surface tension of the solitons leads to an argument for the occurrence of so called snake instability for dark solitons, i.e. for the solitons to form a vortex-like structures. Disordering strongly coupled and correlated quantum states of matter may lead to new insights into the physics of many body localized (MBL) strongly correlated states, which may occur in the presence of strong disorder. We are interested in potential insulator-metal transitions induced by disorder, and how disorder affects the Hawking-Page phase transition in AdS gravity in general. We introduce a metric ansatz and numerically construct the corresponding disordered AdS soliton and AdS black hole solutions, and discuss the calculation of the free energy in these states. In the Kondo effect, the rise in resistivity in metals with scarce magnetic impurities at low temperatures can be explained by the RG flow of the antiferromagnetic coupling between the impurity and conduction electrons in CFT. The generalizations to SU(N) in the large N limit make the treatment amenable to the holographic approach. We add a Maxwell term to a previously existing holographic model to study the conductivity of the itinerant electrons. Our goal is to find the log(T) behavior in the DC resistivity. In the probe limit, we introduce junction conditions to connect fields crossing the defect. We then consider backreactions, which give us a new metric ansatz and new junction conditions for the gauge fields

Extensive selection for the enrichment of G4 DNA motifs in transcriptional regulatory regions of warm blooded animals

AbstractA comprehensive analysis of potential G4 DNA motifs (G4Ms) in genomic regions flanking transcription start sites (TSS) was performed across 13 animal species. We found that G4Ms are significantly enriched in the transcriptional regulatory regions (TRRs) of warm-blooded animals. Further analysis of human genes in different temporal groups reveals that the enrichment is not specific to genes found only in warm-blooded species but instead exist in a wide range of genes. Our findings therefore suggest that the high prevalence of G4Ms in TRRs is extensively selected in warm-blooded animals, supporting the hypothesis that G4Ms are involved in the regulation of gene transcription

Genome-wide analysis of the CML gene family and its response to melatonin in common bean (Phaseolus vulgaris L.)

Abstract Calmodulin-like proteins (CML) are important calcium signal transduction proteins in plants. CML genes have been analyzed in several plants. However, little information on CML in Phaseolus vulgare is available. In this study, we identified 111 PvCMLs distributed on eleven chromosomes. Phylogenetic analysis classified them into seven subfamilies. Cis-acting element prediction showed that PvCML contained elements related to growth and development, response to abiotic stress and hormones. Moreover, the majority of PvCMLs showed different expression patterns in most of the nine tissues and developmental stages which indicated the role of PvCML in the growth and development of common bean. Additionally, the common bean was treated with melatonin by seed soaking, and root transcriptome at the 5th day and qRT-PCR of different tissue at several stages were performed to reveal the response of PvCML to the hormone. Interestingly, 9 PvCML genes of subfamily VI were detected responsive to exogenous melatonin, and the expression dynamics of nine melatonin response PvCML genes after seed soaking with melatonin were revealed. Finally, the protein interaction network analysis of nine melatonin responsive PvCMLs was constructed. The systematic analysis of the PvCML gene family provides theoretical support for the further elucidation of their functions, and melatonin response molecular mechanism of the CML family in P. vulgaris