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Papillary Thyroid Carcinoma Variants are Characterized by Co-dysregulation of Immune and Cancer Associated Genes.
Papillary thyroid carcinoma (PTC) variants exhibit different prognosis, but critical characteristics of PTC variants that contribute to differences in pathogenesis are not well-known. This study aims to characterize dysregulated immune-associated and cancer-associated genes in three PTC subtypes to explore how the interplay between cancer and immune processes causes differential prognosis. RNA-sequencing data from The Cancer Genome Atlas (TCGA) were used to identify dysregulated genes in each variant. The dysregulation profiles of the subtypes were compared using functional pathways clustering and correlations to relevant clinical variables, genomic alterations, and microRNA regulation. We discovered that the dysregulation profiles of classical PTC (CPTC) and the tall cell variant (TCPTC) are similar and are distinct from that of the follicular variant (FVPTC). However, unique cancer or immune-associated genes are associated with clinical variables for each subtype. Cancer-related genes MUC1, FN1, and S100-family members were the most clinically relevant in CPTC, while APLN and IL16, both immune-related, were clinically relevant in FVPTC. RAET-family members, also immune-related, were clinically relevant in TCPTC. Collectively, our data suggest that dysregulation of both cancer and immune associated genes defines the gene expression landscapes of PTC variants, but different cancer or immune related genes may drive the phenotype of each variant
Lac Blanc Pass: a natural wind-tunnel for studying drifting snow at 2700ma.s.l
International audienceThe investigation of the spatial variability of snow depth in high alpine areas is an important topic in snow hydrology, glacier and avalanche research and the transport of snow by wind is an important process for the distribution of snow in mountainous regions. That's why, for 25 years IRSTEA (previously Cemagref) and Météo France (Centre for the Study of Snow) have joined together in studying drifting snow at Col du Lac Blanc 2700 m a.s.l. near the Alpe d'Huez ski resort in the French Alps. Initially, the site was mainly equipped with conventional meteorological stations and a network of snow poles, in order to test numerical models of drifting snow Sytron (CEN) and NEMO (Cemagref). These models are complementary in terms of spatial and temporal scales: outputs of Sytron model will form the inputs of NEMO model. Then new sensors and technologies appeared which allow to develop new knowledge dealing with thresholds velocity according to morphological features of snow grains, snow flux profiles including parameters such as fall velocity and Schmidt number, histograms of particle widths, aerodynamic roughness, gust factors. More recently, the coupled snowpack/ atmosphere model Meso-NH/Crocus has been evaluated at the experimental site. At the same time, some tested sensors have been deployed in Adelie Land in Antarctica, where blowing snow accounts for a major component of the surface mass balance. Japanese and Austrian research teams have been accomodated at Lac Blanc Pass and new foreign teams are welcome. Initial observations continue. That's why Lac Blanc Pass is also a climatological reference for 25 years at 2700 m. Data are available
Excitonic Bound State in the Extended Anderson Model with c-f Coulomb Interaction
The Anderson model with the Coulomb interaction between the local and
conduction electrons is studied in the semiconducting phase. Based on a
perturbation theory from the atomic limit, leading contributions for the c-f
Coulomb interaction are incorporated as a vertex correction to hybridization.
An analytical solution shows that the effective attraction in the intermediate
states leads to a bound state localized at the local electron site.
Self-consistent equations are constructed as an extension of the non-crossing
approximation (NCA) to include the vertex part yielding the bound state. A
numerical calculation demonstrates the excitonic bound state inside the
semiconducting gap for single-particle excitations, and a discontinuity at the
gap edge for magnetic excitations.Comment: 15 pages, 20 figures, submitted to J. Phys. Soc. Jp
Theory for Magnetic Anisotropy of Field-Induced Insulator-to-Metal Transition in Cubic Kondo Insulator YbB_{12}
Magnetization and energy gap of Kondo insulator YbB_{12} are calculated
theoretically based on the previously proposed tight-binding model composed of
Yb 5d and 4f orbitals. It is found that magnetization
curves are almost isotropic, naturally expected from the cubic symmetry, but
that the gap-closing field has an anisotropy: the gap closes faster for the
field in (100) direction than in (110) and (111) directions, in accord with the
experiments. This is qualitatively understood by considering the maximal
eigenvalues of the total angular momentum operators projected on each direction
of the magnetic field. But the numerical calculation based on the band model
yields better agreement with the experiment.Comment: 4 pages, 4 figures, to appear in J. Phys. Soc. Jp
Indirect and direct energy gaps in the Kondo semiconductor YbB12
Optical conductivity [] of the Kondo semiconductor YbB
has been measured over wide ranges of temperature (=8690 K) and photon
energy ( 1.3 meV). The data reveal the
entire crossover of YbB from a metallic electronic structure at high
into a semiconducting one at low . Associated with the gap development in
, a clear onset is newly found at =15 meV for 20 K. The onset energy is identified as the gap width of YbB
appearing in . This gap in \sigma(\omega)\sigma(\omega)$ is interpreted as arising from the direct gap. The
absorption coefficient around the onset and the mIR peak indeed show
characteristic energy dependences expected for indirect and direct optical
transitions in conventional semiconductors.Comment: 4 pages, 3 figures, submitted to J. Phys. Soc. Jp
Study of water pollution by agricultural inputs: case of five intensive agriculture areas in Burkina Faso
Pour optimiser les rendements (agricoles), lâagriculture intensive nĂ©cessite une utilisation massive dâintrants agricoles dont les engrais chimiques, potentiellement sources de pollution des ressources en eau.
La rĂ©gion du Sud - Ouest du Burkina, dont font partie les zones concernĂ©es par la prĂ©sente Ă©tude, connaĂźt une agriculture intensive du coton. Il est fait usage dans les champs de coton, dâengrais Ă base essentiellement dâazote, de phosphate, de potassium, mais Ă©galement dâurĂ©e, de chlorure de potassium et de nitrate dâammonium. Un total de 42 Ă©chantillons dâeau de surface, de puits et de forages ont fait lâobjet dâanalyses, afin dâĂ©valuer lâimpact de ces engrais sur la qualitĂ© des ressources en eau de consommation des populations sur une annĂ©e. Eu Ă©gard Ă la nature des fertilisants utilisĂ©s, les paramĂštres essentiels suivants ont Ă©tĂ© ciblĂ©s : Nitrates, nitrites, ortho-phosphates, ammonium, potassium, conductivitĂ© Ă©lectrique et duretĂ© totale.
Il ressort de ces investigations que les eaux de puits, pendant la saison hivernale, prĂ©sentent des teneurs plus importantes en nitrates et potassium avec des valeurs maximales respectives de 178 mg/L (plus de 3 fois la valeur limite admise par lâOMS pour les eaux de consommation) et 55 mg/L pour une norme admise par lâOMS de 10 mg/L en potassium. Les ortho-phosphates, forme soluble du phosphore et les nitrites, prĂ©sentent des teneurs infĂ©rieures aux normes admises. Sâagissant des ions ammonium, un seul puits par sa position en aval dâun WC et dâun parc dâanimaux, a donnĂ© des valeurs supĂ©rieures Ă la norme qui est fixĂ©e Ă 1,5 mg/L, atteignant ainsi 20 mg/L de N-NH+4. Les Ă©chantillons dâeau de forages sont exempts de toute contamination, alors que 33% des prĂ©lĂšvements dâeau de surface ont donnĂ© des teneurs dĂ©passant la valeur limite admise seulement en potassium. Globalement, 61% des Ă©chantillons dâeau de puits sont contaminĂ©s par les nitrates, 67% par le potassium et 17% donnent des teneurs supĂ©rieures Ă la norme en ammonium. Ce qui permet dâen dĂ©duire quâil y a une infiltration de pollution dans la nappe superficielle qui alimente les puits. La conductivitĂ© Ă©lectrique et la duretĂ© totale sans ĂȘtre excessives prĂ©sentent les valeurs les plus importantes pour les mĂȘmes sites que sont les puits, avec des valeurs maximales respectives
de 1252 ÎŒS/cm et 202 mg/L de CaCO3
Yb-Yb correlations and crystal-field effects in the Kondo insulator YbB12 and its solid solutions
We have studied the effect of Lu substitution on the spin dynamics of the
Kondo insulator YbB12 to clarify the origin of the spin-gap response previously
observed at low temperature in this material. Inelastic neutron spectra have
been measured in Yb1-xLuxB12 compounds for four Lu concentrations x = 0, 0.25,
0.90 and 1.0. The data indicate that the disruption of coherence on the Yb
sublattice primarily affects the narrow peak structure occurring near 15-20 meV
in pure YbB12, whereas the spin gap and the broad magnetic signal around 38 meV
remain almost unaffected. It is inferred that the latter features reflect
mainly local, single-site processes, and may be reminiscent of the inelastic
magnetic response reported for mixed-valence intermetallic compounds. On the
other hand, the lower component at 15 meV is most likely due to dynamic
short-range magnetic correlations. The crystal-field splitting in YbB12
estimated from the Er3+ transitions measured in a Yb0.9Er0.1B12 sample, has the
same order of magnitude as other relevant energy scales of the system and is
thus likely to play a role in the form of the magnetic spectral response.Comment: 16 pages in pdf format, 9 figures. v. 2: coauthor list updated; extra
details given in section 3.2 (pp. 6-7); one reference added; fig. 5 axis
label change
Molecular markers for discriminating Streptococcus pyogenes and S. dysgalactiae subspecies equisimilis
Given the increasing aetiological importance of Streptococcus dysgalactiae subspecies equisimilis in diseases which are primarily attributed to S. pyogenes, molecular markers are essential to distinguish these species and delineate their epidemiology more precisely. Many clinical microbiology laboratories rely on agglutination reactivity and biochemical tests to distinguish them. These methods have limitations which are particularly exacerbated when isolates with mixed properties are encountered. In order to provide additional distinguishing parameters that could be used to unequivocally discriminate these two common pathogens, we assess here three molecular targets: the speB gene, intergenic region upstream of the scpG gene (IRSG) and virPCR. Of these, the former two respectively gave positive and negative results for S. pyogenes, and negative and positive results for S. dysgalactiae subsp. equisimilis. Thus, a concerted use of these nucleic acid-based methods is particularly helpful in epidemiological surveillance to accurately assess the relative contribution of these species to streptococcal infections and diseases
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