97 research outputs found

    The identification of potential cis- and trans-acting factors in the regulation of DARK INDUCIBLE 3 (DIN3) expression during darkness and chilling in Arabidopsis thaliana

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    Plant responses to environmental stimuli are co-ordinated by a variety of sensing and signalling mechanisms, which bring appropriate internal changes so that plants are able to adapt to a changing environment. It was the aim of this project to investigate the regulation of one gene: DARK INDUCIBLE 3 (DIN3), specifically the cis- and transacting factors. To achieve these aims, the investigative approach centred on gene expression analysis of linker-scan mutation analysis of 50 base-pairs (bp) of the minimal functional promoter of DIN3. To investigate the contribution made by transacting factors, the effects of over-expression of candidate transcription factor genes were analysed. This project determined that in addition to dark-induced expression already described in the literature, the dark-induction of DIN3 expression could be repressed by low temperature. Specific motifs within the crucial 50bp of the DIN3 promoter were found to be necessary for dark-induced expression, which together was hypothesised to constitute a sugar-responsive sequence. No cis-acting regulatory motifs were found to contribute definitely to the cold responsiveness of DIN3. None of the transcription factor genes investigated, were revealed to have a major role in the dark and cold responsiveness of DIN3. The results of this project suggest that there is considerable cross-talk between dark/sugar regulation and low temperature at the cisand trans-acting level

    Adoptive applicants and children released for adoption

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    Thesis (M.S.)--Boston Universit

    Measuring relative volatility in high‐frequency data under the directional change approach

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    We introduce a new approach in measuring relative volatility between two markets based on the directional change (DC) method. DC is a data-driven approach for sampling financial market data such that the data are recorded when the price changes have reached a significant amplitude rather than recording data under a predetermined timescale. Under the DC framework, we propose a new concept of DC micro-market relative volatility to evaluate relative volatility between two markets. Unlike the time-series method, micro-market relative volatility redefines the timescale based on the frequency of the observed DC data between the two markets. We show that it is useful for measuring the relative volatility in micro-market activities (high-frequency data)

    What RHIC Experiments and Theory tell us about Properties of Quark-Gluon Plasma ?

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    This brief review summarizes the main experimental discoveries made at RHIC and then discusses their implications. The robust collective flow phenomena are well described by ideal hydrodynamics, with the Equation of State (EoS) predicted by lattice simulations. However the transport properties turned out to be unexpected, with rescattering cross section one-to-two orders of magnitude larger than expected from perturbative QCD. These and other theoretical developments indicate that Quark-Gluon Plasma (QGP) produced at RHIC, and probably in a wider temperature region Tc<T<4TcT_c<T<4T_c, is not at all a weakly coupled quasiparticle gas, but is rather in a strongly coupled regime, sQGP for short. After reviewing two other ``strongly coupled systems'', (i) the strongly coupled supersymmetric theories studied via Maldacena duality; (ii) trapped ultra-cold atoms with very large scattering length, we return to sQGP and show that there should exist literally hundreds of bound states in it in the RHIC domain, most them colored. We then discuss recent ideas of their effect on the EoS, viscosity and jet quenching.Comment: Prepared for workshop on RHIC discoveries, BNL May 14,1

    A molecular map of murine lymph node blood vascular endothelium at single cell resolution

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    Blood vascular endothelial cells (BECs) control the immune response by regulating blood flow and immune cell recruitment in lymphoid tissues. However, the diversity of BEC and their origins during immune angiogenesis remain unclear. Here we profile transcriptomes of BEC from peripheral lymph nodes and map phenotypes to the vasculature. We identify multiple subsets, including a medullary venous population whose gene signature predicts a selective role in myeloid cell (vs lymphocyte) recruitment to the medulla, confirmed by videomicroscopy. We define five capillary subsets, including a capillary resident precursor (CRP) that displays stem cell and migratory gene signatures, and contributes to homeostatic BEC turnover and to neogenesis of high endothelium after immunization. Cell alignments show retention of developmental programs along trajectories from CRP to mature venous and arterial populations. Our single cell atlas provides a molecular roadmap of the lymph node blood vasculature and defines subset specialization for leukocyte recruitment and vascular homeostasis

    The \bar q q Bound States and Instanton Molecule at T >~ T_c

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    The main objective of this work is to explore the evolution in the structure of the quark-anti-quark bound states in going down in the chirally restored phase from the so-called "zero binding points" TzbT_{zb} to the full (unquenched) QCD critical temperature TcT_c at which the Nambu-Goldstone and Wigner-Weyl modes meet. In doing this, we adopt the idea recently introduced by Shuryak and Zahed for charmed cˉc\bar c c, light-quark qˉq\bar q q mesons π,σ,ρ,A1\pi, \sigma, \rho, A_1 and gluons that at TzbT_{zb}, the quark-anti-quark scattering length goes through \infty at which conformal invariance is restored, thereby transforming the matter into a near perfect fluid behaving hydrodynamically, as found at RHIC. We show that the binding of these states is accomplished by the combination of (i) the color Coulomb interaction, (ii) the relativistic effects, and (iii) the interaction induced by the instanton-anti-instanton molecules. The spin-spin forces turned out to be small. While near TzbT_{zb} all mesons are large-size nonrelativistic objects bound by Coulomb attraction, near TcT_c they get much more tightly bound, with many-body collective interactions becoming important and making the σ\sigma and π\pi masses approach zero (in the chiral limit). The wave function at the origin grows strongly with binding, and the near-local four-Fermi interactions induced by the instanton molecules play an increasingly more important role as the temperature moves downward toward TcT_c.Comment: 31 pages, 7 figures, final refereed versio

    A prospective stroke register in Sierra Leone: Demographics, stroke type, stroke care and hospital outcomes

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    Introduction Stroke is the second most common cause of adult death in Africa. This study reports the demographics, stroke types, stroke care and hospital outcomes for stroke in Freetown, Sierra Leone. Methods A prospective observational register recorded all patients 18 years and over with stroke between May 2019 and April 2020. Stroke was defined according to the WHO criteria. Pearson’s chi squared test was used to examine associations between categorical variables and unpaired t-tests for continuous variables. Multivariable logistic regression,to explain in-hospital death, was reported as odds ratios (OR) and 95% confidence intervals. Results 385 strokes were registered, 315 (81.8%) were first in a lifetime events. Mean age was 59.2 (SD 13.8) and 187 (48.6%) were male. 327 (84.9%) of strokes were confirmed by CT scan. 231 (60.0%) were ischaemic, 85 (22.1%) intracerebral haemorrhage, 11 (2.9%) subarachnoid haemorrhage and 58 (15.1%) undetermined stroke type. The median National Institute of Health Stroke Scale on presentation was 17 (IQR 9-25). Haemorrhagic strokes compared to ischaemic strokes were more severe, 20 (IQR 12-26) vs 13 (IQR 7-22) (p<0.001), and occurred in a younger population, mean age 52.3 (SD 12.0) vs 61.6 (SD 13.8) (p<0.001), with a lower level of educational attainment 28.2% vs 40.7% (p=0.04). The median time from stroke onset to arrival at the principal referral hospital was 25 hours (IQR 6-73). Half the patients (50.4%) sought care at another health provider prior to arrival. 151 patients died in hospital (39.5%). 43 deaths occurred within 48 hours of arriving at hospital with median time to death of 4 days (IQR 0-7 days). 49.6% of patients had ≥1 complication, 98 (25.5%) pneumonia, 33 (8.6%) urinary tract infection. Male gender (OR 3.33,1.65 - 6.75), pneumonia (OR 3.75, 1.82 – 7.76), subarachnoid haemorrhage (OR 43.1, 6.70-277.4) and undetermined stroke types (OR 6.35, 2.17– 18.60), were associated with higher risk of in-hospital death. Discussion We observed severe strokes occurring in a young population with high in hospital mortality. Further work to deliver evidence-based stroke care is essential to reduce stroke mortality in Sierra Leone

    Global wealth disparities drive adherence to COVID-safe pathways in head and neck cancer surgery

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