179 research outputs found
Graphene as a quantum surface with curvature-strain preserving dynamics
We discuss how the curvature and the strain density of the atomic lattice
generate the quantization of graphene sheets as well as the dynamics of
geometric quasiparticles propagating along the constant curvature/strain
levels. The internal kinetic momentum of Riemannian oriented surface (a vector
field preserving the Gaussian curvature and the area) is determined.Comment: 13p, minor correction
Essential oil of Lippia grata (Verbenaceae) is effective in the control of monogenean infections in Colossoma macropomum gills, a large Serrasalmidae fish from Amazon.
This study investigated the efficacy of Lippia grata essential oil (EO) against monogeneans of Colossoma macropomum and effects on the haematology after immersion baths. In the in vitro assays, the efficacy of 100, 250, 350 and 700 mg/L of L. grata EO and two controls were tested, of which one control was with the cultivation tank water and the other was with the tank water and 70% ethyl alcohol. Composition of majority bioactive compounds in the EO was carvacrol (48.12%), pcymene (24.39%) and γ-terpinene (2.49%). Anacanthorus spathulatus, Notozothecium janauachensis, Mymarothecium boegeri and Linguadactyloides brinkmanni obtained of fish gills showed 100% immobilization in the in vitro assays when exposed to 700 and 350 mg/L after 30 min and 2 hr respectively. Fish showed tolerance to 700 mg/L of the EO, which was used in therapeutic in three consecutive baths, which caused lamellar hyperplasia in C. macropomum gills. The 700 mg/L of the EO in the therapeutic baths showed an efficacy of 95.1% against the monogeneans and caused decrease in haemoglobin, whereas control fish showed a reduction in mean corpuscular haemoglobin concentration. Results indicated that 700 mg/L of L. grata EO is a safe and effective concentration to treat C. macropomum infected with monogeneans
Measurement of Resonance Parameters of Orbitally Excited Narrow B^0 Mesons
We report a measurement of resonance parameters of the orbitally excited
(L=1) narrow B^0 mesons in decays to B^{(*)+}\pi^- using 1.7/fb of data
collected by the CDF II detector at the Fermilab Tevatron. The mass and width
of the B^{*0}_2 state are measured to be m(B^{*0}_2) =
5740.2^{+1.7}_{-1.8}(stat.) ^{+0.9}_{-0.8}(syst.) MeV/c^2 and \Gamma(B^{*0}_2)
= 22.7^{+3.8}_{-3.2}(stat.) ^{+3.2}_{-10.2}(syst.) MeV/c^2. The mass difference
between the B^{*0}_2 and B^0_1 states is measured to be
14.9^{+2.2}_{-2.5}(stat.) ^{+1.2}_{-1.4}(syst.) MeV/c^2, resulting in a B^0_1
mass of 5725.3^{+1.6}_{-2.2}(stat.) ^{+1.4}_{-1.5}(syst.) MeV/c^2. This is
currently the most precise measurement of the masses of these states and the
first measurement of the B^{*0}_2 width.Comment: 7 pages, 1 figure, 1 table. Submitted to Phys.Rev.Let
Two super-Earths at the edge of the habitable zone of the nearby M dwarf TOI-2095
The main scientific goal of TESS is to find planets smaller than Neptune
around stars bright enough to allow further characterization studies. Given our
current instrumentation and detection biases, M dwarfs are prime targets to
search for small planets that are in (or nearby) the habitable zone of their
host star. Here we use photometric observations and CARMENES radial velocity
measurements to validate a pair of transiting planet candidates found by TESS.
The data was fitted simultaneously using a Bayesian MCMC procedure taking into
account the stellar variability present in the photometric and spectroscopic
time series. We confirm the planetary origin of the two transiting candidates
orbiting around TOI-2095 (TIC 235678745). The star is a nearby M dwarf ( pc, K, mag) with a
stellar mass and radius of and , respectively. The planetary system is composed of
two transiting planets: TOI-2095b with an orbital period of days and TOI-2095c with days. Both planets have similar sizes with and for planet b and c,
respectively. We put upper limits on the masses of these objects with for the inner and for the outer planet
(95\% confidence level). These two planets present equilibrium temperatures in
the range of 300 - 350 K and are close to the inner edge of the habitable zone
of their star.Comment: Submitted to Astronomy & Astrophysic
Greenhouse gas mitigation scenarios for major emitting countries – Analysis of current climate policies and mitigation commitments: 2021 Update
This report by NewClimate Institute, PBL Netherlands Environmental Assessment Agency and the International Institute for Applied Systems Analysis (IIASA) provides an overview of projected greenhouse gas (GHG) emissions in 26 major emitting countries and regions up to 2030 under currently implemented policies. The report shows that emissions are projected to remain above 2005 levels in most countries but concludes that 16 out of the 26 countries and regions analysed are on track or close to achieve the NDC targets they have previously set for themselves. Eight are on track to also meet their updated NDC targets (with another two countries being close). 11 countries are not on track to meet their updated targets, and five of the 26 countries have not submitted an NDC update
The BET inhibitor JQ1 selectively impairs tumour response to hypoxia and downregulates CA9 and angiogenesis in triple negative breast cancer
The availability of bromodomain and extra-terminal inhibitors (BETi) has enabled translational epigenetic studies in cancer. BET proteins regulate transcription by selectively recognizing acetylated lysine residues on chromatin. BETi compete with this process leading to both downregulation and upregulation of gene expression. Hypoxia enables progression of triple negative breast cancer (TNBC), the most aggressive form of breast cancer, partly by driving metabolic adaptation, angiogenesis and metastasis through upregulation of hypoxia-regulated genes (for example, carbonic anhydrase 9 (CA9) and vascular endothelial growth factor A (VEGF-A). Responses to hypoxia can be mediated epigenetically, thus we investigated whether BETi JQ1 could impair the TNBC response induced by hypoxia and exert anti-tumour effects. JQ1 significantly modulated 44% of hypoxia-induced genes, of which two-thirds were downregulated including CA9 and VEGF-A. JQ1 prevented HIF binding to the hypoxia response element in CA9 promoter, but did not alter HIF expression or activity, suggesting some HIF targets are BET-dependent. JQ1 reduced TNBC growth in vitro and in vivo and inhibited xenograft vascularization. These findings identify that BETi dually targets angiogenesis and the hypoxic response, an effective combination at reducing tumour growth in preclinical studies
Clinical Features and Natural History of Preadolescent Nonsyndromic Hypertrophic Cardiomyopathy
BACKGROUND Up to one-half of childhood sarcomeric hypertrophic cardiomyopathy (HCM) presents before the age of 12 years, but this patient group has not been systematically characterized. OBJECTIVES The aim of this study was to describe the clinical presentation and natural history of patients presenting with nonsyndromic HCM before the age of 12 years. METHODS Data from the International Paediatric Hypertrophic Cardiomyopathy Consortium on 639 children diagnosed with HCM younger than 12 years were collected and compared with those from 568 children diagnosed between 12 and 16 years. RESULTS At baseline, 339 patients (53.6%) had family histories of HCM, 132 (20.9%) had heart failure symptoms, and 250 (39.2%) were prescribed cardiac medications. The median maximal left ventricular wall thickness z-score was 8.7 (IQR: 5.3-14.4), and 145 patients (27.2%) had left ventricular outflow tract obstruction. Over a median follow-up period of 5.6 years (IQR: 2.3-10.0 years), 42 patients (6.6%) died, 21 (3.3%) underwent cardiac transplantation, and 69 (10.8%) had life-threatening arrhythmic events. Compared with those presenting after 12 years, a higher proportion of younger patients underwent myectomy (10.5% vs 7.2%; P = 0.045), but fewer received primary prevention implantable cardioverter-defibrillators (18.9% vs 30.1%; P = 0.041). The incidence of mortality or life-threatening arrhythmic events did not differ, but events occurred at a younger age. CONCLUSIONS Early-onset childhood HCM is associated with a comparable symptom burden and cardiac phenotype as in patients presenting later in childhood. Long-term outcomes including mortality did not differ by age of presentation, but patients presenting at younger than 12 years experienced adverse events at younger ages. (C) 2022 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation.Peer reviewe
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