4,114 research outputs found

    Almost isomorphism for countable state Markov shifts

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    Countable state Markov shifts are a natural generalization of the well-known subshifts of finite type. They are the subject of current research both for their own sake and as models for smooth dynamical systems. In this paper, we investigate their almost isomorphism and entropy conjugacy and obtain a complete classification for the especially important class of strongly positive recurrent Markov shifts. This gives a complete classification up to entropy conjugacy of the natural extensions of smooth entropy expanding maps, including all smooth interval maps with non-zero topological entropy

    Good potentials for almost isomorphism of countable state Markov shifts

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    Almost isomorphism is an equivalence relation on countable state Markov shifts which provides a strong version of Borel conjugacy; still, for mixing SPR shifts, entropy is a complete invariant of almost isomorphism. In this paper, we establish a class of potentials on countable state Markov shifts whose thermodynamic formalism is respected by almost isomorphism

    Tracing out the Northern Tidal Stream of the Sagittarius Dwarf Spheoridal Galaxy

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    The main aim of this paper is to report two new detections of tidal debris in the northern stream of the Sagittarius dwarf galaxy located at 45 arcdeg and 55 arcdeg from the center of galaxy. Our observational approach is based on deep color-magnitude diagrams, that provides accurate distances, surface brightness and the properties of stellar population of the studied region of this tidal stream. The derived distances for these tidal debris wraps are 45 kpc and 54 kpc respectively.We also confirm these detections with numerical simulations of the Sagittarius dwarf plus the Milky Way. The model reproduces the present position and velocity of the Sagittarius main body and presents a long tidal stream formed by tidal interaction with the Milky Way potential. This model is also in good agreement with the available observations of the Sagittarius tidal stream. We also present a method for estimating the shape of the Milky Way halo potential using numerical simulations. From our simulations we obtain an oblateness of the Milky Way dark halo potential of 0.85, using the current database of distances and radial velocities of the Sagittarius tidal stream. The color-magnitude diagram of the apocenter of Sagittarius shows that this region of the stream shares the complex star formation history observed in the main body of the galaxy. We present the first evidence for a gradient in the stellar population along the stream, possibly correlated with its different pericenter passages. (abridged)Comment: 43 pages (including 15 figures; for high resolution color figures, please contact [email protected]). Submitted to Ap

    Valorisation Potential of Invasive Acacia dealbata, A. longifolia and A. melanoxylon from Land Clearings

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    Acacia spp. are invasive in Southern Europe, and their high propagation rates produce excessive biomass, exacerbating wildfire risk. However, lignocellulosic biomass from Acacia spp. may be utilised for diverse biorefinery applications. In this study, attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR), high-performance anion-exchange chromatography pulsed amperometric detection (HPAEC-PAD) and lignin content determinations were used for a comparative compositional characterisation of A. dealbata, A. longifolia and A. melanoxylon. Additionally, biomass was treated with three white-rot fungi species ( Ganoderma lucidum, Pleurotus ostreatus and Trametes versicolor), which preferentially degrade lignin. Our results showed that the pre-treatments do not significantly alter neutral sugar composition while reducing lignin content. Sugar release from enzymatic saccharification was enhanced, in some cases possibly due to a synergy between white-rot fungi and mild alkali pretreatments. For example, in A. dealbata stems treated with alkali and P. ostreatus, saccharification yield was 702.3 nmol mg -1, which is higher than the samples treated only with alkali (608.1 nmol mg -1), and 2.9-fold higher than the non-pretreated controls (243.9 nmol mg -1). By characterising biomass and pretreatments, generated data creates value for unused biomass resources, contributing to the implementation of sustainable biorefining systems. In due course, the generated value will lead to economic incentives for landowners to cut back invasive Acacia spp. more frequently, thus reducing excess biomass, which exacerbates wildfire risk

    Biorefining Potential of Wild-Grown Arundo donax, Cortaderia selloana and Phragmites australis and the Feasibility of White-Rot Fungi-Mediated Pretreatments

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    Arundo donax, Cortaderia selloana and Phragmites australis are high-biomass-producing perennial Poalean species that grow abundantly and spontaneously in warm temperate regions, such as in Mediterranean-type climates, like those of Southern Europe, Western United States coastal areas, or in regions of South America, South Africa and Australia. Given their vigorous and spontaneous growth, biomass from the studied grasses often accumulates excessively in unmanaged agro-forestry areas. Nonetheless, this also creates the demand and opportunity for the valorisation of these biomass sources, particularly their cell wall polymers, for biorefining applications. By contrast, a related crop, Miscanthus × giganteus, is a perennial grass that has been extensively studied for lignocellulosic biomass production, as it can grow on low-input agricultural systems in colder climates. In this study Fourier transform mid-infrared spectroscopy (FTIR), high-performance anion-exchange chromatography (HPAEC) and lignin content determinations were used for a comparative compositional characterisation of A. donax, C. selloana and P. australis harvested from the wild, in relation to a trial field-grown M. × giganteus high-yielding genotype. A high-throughput saccharification assay showed relatively high sugar release values from the wild-grown grasses, even with a 0.1M NaOH mild alkali pretreatment. In addition to this alkaline pretreatment, biomass was treated with white-rot fungi (WRF), which preferentially degrade lignin more readily than holocellulose. Three fungal species were used: Ganoderma lucidum, Pleurotus ostreatus and Trametes versicolor. Our results showed that neutral sugar contents are not significantly altered, while some lignin is lost during the pretreatments. Furthermore, sugar release upon enzymatic saccharification was enhanced, and this was dependent on the plant biomass and fungal species used in the treatment. To maximise the potential for lignocellulose valorisation, the liquid fractions from the pretreatments were analysed by high performance liquid chromatography – photodiode array detection – electrospray ionisation tandem mass spectrometry (HPLC-PDA-ESI-MS(n)). This study is one of the first to report on the composition of WRF-treated grass biomass, while assessing the potential relevance of breakdown products released during the treatments, beyond more traditional sugar-for-energy applications. Ultimately, we expect that our data will help promote the valorisation of unused biomass resources, create economic value, while contributing to the implementation of sustainable biorefining systems

    Reduced expression of mir15a in the blood of patients with oral squamous cell carcinoma is associated with tumor staging

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    MicroRNAs (miRNAs) mirl 5a and let7a are iMportant regulators of bcl-2, ras and c-myc proteins Considering that these miRNAs are commonly altered in many human cancers and that these proteins are reported to be altered in oral squamous cell carcinoma (OSCC), we investigated them in a set of OSCC cases \u27I he miRNAs as well as the proteins were evaluated in the tumor and blood of 20 patients by real-time quantitative PCR and iMmunohistochemistry, respectively The expression of nfirl5a and bcl-2 proteins in the tumors was not associated with each other or with tumor staging On the other hand, we found reduced expression of this miRNA in the blood of patients with an advanced stage of OSCC and with lymph node metastasis The expression of let7a in the tumor and blood was not associated with tumor size lymph node metastasis, tumor staging and immunoexpression of ras and c-myc proteins In conclusion, the present study shows that reduced expression of Mir15a is associated with OSCC stagin

    Controlling the crystalline and magnetic texture in sputtered Fe 0.89 Ga 0.11 thin films: Influence of substrate and thermal treatment

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    In this work we present a careful study on the relationship between the magnetic and structural properties of a highly magnetostrictive Fe0.89Ga0.11 (Fe-Ga) alloy deposited onto glass, Si and MgO substrates. When grown on glass, the films are polycrystalline with randomly oriented grains without any texture, while the ones on Si and MgO present preferred growth directions. Fe-Ga/Si films show a [1 1 3] fibre-like texture, and Fe-Ga/MgO presents a quasi monocrystalline behavior with the (1 0 0) film plane direction parallel to the substrate surface. When Fe-Ga/MgO films are annealed an additional (1 1 0) texture is also observed. Magnetometry and ferromagnetic resonance (FMR) show that the magnetic behavior is closely related to the structural observed textures. Furthermore, the structural analysis allowed us to get a deeper understanding of the magnetic behavior. This point is very important to get the ability of controlling the crystalline texture by means of growing onto different substrates and/or thermal treatments, which in turns opens the possibility of handling the magnetic texture which is particularly important in magnetostrictive materials for electronic devices.Fil: Ramírez Chamorro, Gerardo Alexis. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología; ArgentinaFil: Malamud, Florencia. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Gomez, Javier Enrique. Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología; ArgentinaFil: Rodríguez, Luis M.. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Fregenal, Daniel Eduardo. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Butera, Alejandro Ricardo. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología; ArgentinaFil: Milano, Julian. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología; Argentin

    Angular moments of the decay Λb 0 → Λμ + μ − at low hadronic recoil

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    An analysis of the angular distribution of the decay Λ0 b → Λµ +µ − is presented, using data collected with the LHCb detector between 2011 and 2016 and corresponding to an integrated luminosity of approximately 5 fb−1 . Angular observables are determined using a moment analysis of the angular distribution at low hadronic recoil, corresponding to the dimuon invariant mass squared range 15 < q2 < 20 GeV2/c4 . The full basis of observables is measured for the first time. The lepton-side, hadron-side and combined forward-backward asymmetries of the decay are determined to b

    Biological variation in HbA1c predicts risk of retinopathy and nephropathy in type 1 diabetes

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    WSTĘP. Autorzy niniejszej pracy założyli, że ryzyko powikłań mikronaczyniowych w badaniu Diabetes Control and Complications Trial (DCCT) jest uwarunkowane zarówno zmiennością hemoglobiny glikowanej (HbA1c), zależną od średniego stężenia glukozy we krwi (MBG, mean blood glucose), jak i biologiczną zmiennością osobniczą HbA1c. MATERIAŁ I METODY. Wartości MBG i HbA1c, oznaczone u uczestników badania DCCT (n = 1441) podczas wizyt odbywających się co 3 miesiące, poddano analizie według modelu liniowej regresji wieloczynnikowej. W celu oceny zmienności biologicznej podczas każdej wizyty obliczono indeks glikacji hemoglobiny (HGI, hemoglobin glycation index = wartość zmierzona HbA1c&#8211; wartość przewidywana HbA1c), aby ocenić biologiczną zmienność, opierając się na kierunkowych odchyleniach zmierzonej HbA1c od wartości przewidywanej na podstawie MBG. Populację podzielono w zależności od średnich wartości HGI podczas trwania badania na 3 części: o wysokim, średnim i niskim HGI. Dla poszczególnych grup przeprowadzono analizę z zastosowaniem modelu proporcjonalnego hazardu Coxa w celu porównania ryzyka wystąpienia oraz rozwoju retinopatii i nefropatii w zależności od MBG, wieku, sposobu leczenia, grupy prewencji pierwotnej lub interwencji i czasu trwania cukrzycy. WYNIKI. Współczynnik prawdopodobieństwa oraz analizy HGI w testach t podważają twierdzenie, że wartość HbA1c zależy jedynie od MBG. Podczas 7-letniej obserwacji u pacjentów z wysokimi wartościami HbA1c (wyższymi niż oczekiwane) było 3-krotnie wyższe ryzyko retinopatii (30 vs. 9%; p < 0,001) i 6-krotnie wyższe ryzyko nefropatii (6 vs. 1%, p < 0,001) w porównaniu z grupą o niskim HGI. WNIOSKI. Osobnicza biologiczna zmienność HbA1c, odmienna i niezależna od zmienności HbA1c warunkowanej średnią glikemią, występuje niewątpliwie u chorych na cukrzycę typu 1 biorących udział w badaniu DCCT. Ponadto jest silnym czynnikiem ryzyka rozwoju cukrzycy. Określenie procesów odpowiedzialnych za biologiczną zmienność HbA1c mogłoby prowadzić do stworzenia nowych kierunków leczenia hipoglikemizującego oraz opóźniającego powikłania i postęp choroby.INTRODUCTION. We hypothesized that biological variation in HbA1c, distinct from variation attributable to mean blood glucose (MBG), would predict risk for microvascular complications in the Diabetes Control and Complications Trial (DCCT). MATERIAL AND METHODS. A longitudinal multiple regression model was developed from MBG and HbA1c measured in the 1,441 DCCT participants at quarterly visits. A hemoglobin glycation index (HGI = observed HbA1c&#8211;predicted HbA1c) was calculated for each visit to assess biological variation based on the directional deviation of observed HbA1c from that predicted by MBG in the model. The population was subdivided by thirds into high-, moderate-, and low- HGI groups based on mean participant HGI during the study. Cox proportional hazard analysis compared risk for development or progression of retinopathy and nephropathy between HGI groups controlled for MBG, age, treatment group, strata, and duration of diabetes. RESULTS. Likelihood ratio and t tests on HGI rejected the assumption that HbA1c levels were determined by MBG alone. At 7 years&#8217; follow-up, patients in the high-HGI group (higher than-predicted HbA1c) had three times greater risk of retinopathy (30 vs. 9%; P < 0.001) and six times greater risk of nephropathy (6 vs. 1%; P < 0.001) compared with the low- HGI group. CONCLUSIONS. Between-individual biological variation in HbA1c, which is distinct from that attributable to MBG, was evident among type 1 diabetic patients in the DCCT and was a strong predictor of risk for diabetes complications. Identification of the processes responsible for biological variation in HbA1c could lead to novel therapies to augment treatments directed at lowering blood glucose levels and preventing diabetes complications

    Observation of the decay Bs0→D¯0K+K−

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    The first observation of the B0 s → D¯ 0KþK− decay is reported, together with the most precise branching fraction measurement of the mode B0 → D¯ 0KþK−. The results are obtained from an analysis of pp collision data corresponding to an integrated luminosity of 3.0 fb−1. The data were collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV. The branching fraction of the B0 → D¯ 0KþK− decay is measured relative to that of the decay B0 → D¯ 0πþπ− to be BðB0→D¯ 0KþK−Þ BðB0→D¯ 0πþπ−Þ ¼ ð6.9 0.4 0.3Þ%, where the first uncertainty is statistical and the second is systematic. The measured branching fraction of the B0 s → D¯ 0KþK− decay mode relative to that of the corresponding B0 decay is BðB0 s→D¯ 0KþK−Þ BðB0→D¯ 0KþK−Þ ¼ ð93.0 8.9 6.9Þ%. Using the known branching fraction of B0 → D¯ 0πþπ−, the values of BðB0 →D¯ 0KþK−Þ¼ð6.10.40.30.3Þ×10−5 and BðB0 s →D¯ 0KþK−Þ¼ð5.70.50.40.5Þ×10−5 are obtained, where the third uncertainties arise from the branching fraction of the decay modes B0 → D¯ 0πþπ− and B0 → D¯ 0KþK−, respectively
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