427 research outputs found

    GRO J1744-28: an intermediate B-field pulsar in a low mass X-ray binary

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    The bursting pulsar, GRO J1744-28, went again in outburst after \sim18 years of quiescence in mid-January 2014. We studied the broad-band, persistent, X-ray spectrum using X-ray data from a XMM-Newton observation, performed almost at the peak of the outburst, and from a close INTEGRAL observation, performed 3 days later, thus covering the 1.3-70.0 keV band. The spectrum shows a complex continuum shape that cannot be modelled with standard high-mass X-ray pulsar models, nor by two-components models. We observe broadband and peaked residuals from 4 to 15 keV, and we propose a self-consistent interpretation of these residuals, assuming they are produced by cyclotron absorption features and by a moderately smeared, highly ionized, reflection component. We identify the cyclotron fundamental at \sim 4.7 keV, with hints for two possible harmonics at 10.4 keV and 15.8 keV. The position of the cyclotron fundamental allows an estimate for the pulsar magnetic field of (5.27 ±\pm 0.06) ×\times 1011^{11} G, if the feature is produced at its surface. From the dynamical and relativistic smearing of the disk reflected component, we obtain a lower limit estimate for the truncated accretion disk inner radius, (\gtrsim 100 Rg_g), and for the inclination angle (18^{\circ}-48^{\circ}). We also detect the presence of a softer thermal component, that we associate with the emission from an accretion disk truncated at a distance from the pulsar of 50-115 Rg_g. From these estimates, we derive the magneto-spheric radius for disk accretion to be \sim 0.2 times the classical Alfv\'en radius for radial accretion.Comment: Accepted for publication in MNRA

    Study of the physical properties of soils through interpretation of aerial photographs

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    Final technical reportThe purpose of the research work proposed is the study of the physical properties of the soils by means of the interpretation of aerial photographs. This study is to be carried out in two years and thus it is not possible to give definite conclusions at the end of the first year, although the results we have obtained are highly satisfactory. In our opinion and after the experience of the first year, the working problem of the study of the physical properties of the soils through aerial photographs, can be examined from two different aspects. The first of them could be called the "deductive" method and consists in acquiring knowledge of the physical properties of the soils by means of sucoessive interpretations of aerial photographs; through photointerpretation we study the physical Geography of an area, its hydrographic net, natural vegetation and .man-introduced cultivations, the forms of erosion end the nature of the geological material, All these interpretations, together with the clitmate, allow to "deduce" the nature of the soils of that area, as all the pedological processes which the different geological materials have undergone can be know perfectly well, which also shows the intensity of physical and chemical desintegration of the materials that form the starting point of soil formation.The research reported in this document has been made possible through the support and sponsorship of the U.S. Department of the Army through its European Research Office.Contract No. DA-91-591-EUC-2652 1st. April 1963 to 31th March 1964.N

    GROJ1744−28: an intermediate B-field pulsar in a low-mass X-ray binary

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    The bursting pulsar, GROJ1744−28, went again in outburst after ∼18yr of quiescence in 2014 mid-January. We studied the broad-band, persistent, X-ray spectrum using X-ray data from a XMM-Newton observation, performed almost at the peak of the outburst, and from a close INTEGRAL observation, performed 3d later, thus covering the 1.3-70.0keV band. The spectrum shows a complex continuum shape that cannot be modelled with standard high-mass X-ray pulsar models, nor by two-components models. We observe broad-band and peaked residuals from 4 to 15keV, and we propose a self-consistent interpretation of these residuals, assuming they are produced by cyclotron absorption features and by a moderately smeared, highly ionized, reflection component. We identify the cyclotron fundamental at ∼4.7keV, with hints for two possible harmonics at ∼10.4 and ∼15.8keV. The position of the cyclotron fundamental allows an estimate for the pulsar magnetic field of (5.27±0.06)×1011G, if the feature is produced at its surface. From the dynamical and relativistic smearing of the disc reflected component, we obtain a lower limit estimate for the truncated accretion disc inner radius (≳100Rg) and for the inclination angle (18°-48°). We also detect the presence of a softer thermal component that we associate with the emission from an accretion disc truncated at a distance from the pulsar of 50-115Rg. From these estimates, we derive the magnetospheric radius for disc accretion to be ∼0.2times the classical Alfvén radius for radial accretio

    Microtubules in Bacteria: Ancient Tubulins Build a Five-Protofilament Homolog of the Eukaryotic Cytoskeleton

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    Microtubules play crucial roles in cytokinesis, transport, and motility, and are therefore superb targets for anti-cancer drugs. All tubulins evolved from a common ancestor they share with the distantly related bacterial cell division protein FtsZ, but while eukaryotic tubulins evolved into highly conserved microtubule-forming heterodimers, bacterial FtsZ presumably continued to function as single homopolymeric protofilaments as it does today. Microtubules have not previously been found in bacteria, and we lack insight into their evolution from the tubulin/FtsZ ancestor. Using electron cryomicroscopy, here we show that the tubulin homologs BtubA and BtubB form microtubules in bacteria and suggest these be referred to as “bacterial microtubules” (bMTs). bMTs share important features with their eukaryotic counterparts, such as straight protofilaments and similar protofilament interactions. bMTs are composed of only five protofilaments, however, instead of the 13 typical in eukaryotes. These and other results suggest that rather than being derived from modern eukaryotic tubulin, BtubA and BtubB arose from early tubulin intermediates that formed small microtubules. Since we show that bacterial microtubules can be produced in abundance in vitro without chaperones, they should be useful tools for tubulin research and drug screening

    CPU, GPU i FPGA implementacija MALD algoritma za otkrivanje nepravilnosti na površini keramičkih pločica

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    This paper addresses adjustments, implementation and performance comparison of the Moving Average with Local Difference (MALD) method for ceramic tile surface defects detection. Ceramic tile production process is completely autonomous, except the final stage where human eye is required for defects detection. Recent computational platform development and advances in machine vision provides us with several options for MALD algorithm implementation. In order to exploit the shortest execution time for ceramic tile production process, the MALD method is implemented on three different platforms: CPU, GPU and FPGA, and it is implemented on each platform in at least two ways. Implementations are done in MATLAB’s MEX/C++, C++, CUDA/C++, VHDL and Assembly programming languages. Execution times are measured and compared for different algorithms and their implementations on different computational platforms.U ovom radu razmatra se prilagodba, implementacija i usporedba performansi metode pomičnog usrednjavanja s lokalnom diferencijom (MALD) s primjenom u otkrivanju površinskih nedostataka na keramičkim pločicama. Proizvodna linija keramičkih pločica je autonomna sve do zadnje faze u kojoj je potreban ljudski vid kako bi se otkrili eventualni nedostaci na keramičkim pločicama. Nedavnim razvojem računalnih platformi i razvojem metoda računalnog vida omogućena je implementacija MALD metode na nekoliko načina. U nastojanju skraćenja vremena potrebnog za proizvodnju keramičkih pločica, MALD metoda je implementirana u trima različitim platformama: CPU (central processing unit), GPU (graphic processing unit) i FPGA (field programmable gate array), te s barem dva različita algoritma. Implementacija je izvršena sa MATLAB MEX/C++, C++, CUDA/C++, VHDL te Asembler programskim jezicima. Izmjerena vremena obrade su me.usobno uspore.ena za različite algoritme i njihove implementacije na različitim računalnim platformama

    Drought impact on forest carbon dynamics and fluxes in Amazonia

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    In 2005 and 2010 the Amazon basin experienced two strong droughts, driven by shifts in the tropical hydrological regime possibly associated with global climate change, as predicted by some global models. Tree mortality increased after the 2005 drought, and regional atmospheric inversion modelling showed basin-wide decreases in CO2 uptake in 2010 compared with 2011 (ref. 5). But the response of tropical forest carbon cycling to these droughts is not fully understood and there has been no detailed multi-site investigation in situ. Here we use several years of data from a network of thirteen 1-ha forest plots spread throughout South America, where each component of net primary production (NPP), autotrophic respiration and heterotrophic respiration is measured separately, to develop a better mechanistic understanding of the impact of the 2010 drought on the Amazon forest. We find that total NPP remained constant throughout the drought. However, towards the end of the drought, autotrophic respiration, especially in roots and stems, declined significantly compared with measurements in 2009 made in the absence of drought, with extended decreases in autotrophic respiration in the three driest plots. In the year after the drought, total NPP remained constant but the allocation of carbon shifted towards canopy NPP and away from fine-root NPP. Both leaf-level and plot-level measurements indicate that severe drought suppresses photosynthesis. Scaling these measurements to the entire Amazon basin with rainfall data, we estimate that drought suppressed Amazon-wide photosynthesis in 2010 by 0.38 petagrams of carbon (0.23-0.53 petagrams of carbon). Overall, we find that during this drought, instead of reducing total NPP, trees prioritized growth by reducing autotrophic respiration that was unrelated to growth. This suggests that trees decrease investment in tissue maintenance and defence, in line with eco-evolutionary theories that trees are competitively disadvantaged in the absence of growth. We propose that weakened maintenance and defence investment may, in turn, cause the increase in post-drought tree mortality observed at our plots.Gordon and Betty Moore FoundationNatural Environment Research Council (NERC)EU FP7 Amazalert (282664) projectEU FP7GEOCARBON (283080) projectNational Council for Scientific and Technological Development (CNPq, Brazil)ARC - fellowship awardERC - Advanced Investigator AwardRoyal Society - Wolfson Research Merit AwardJackson FoundationJohn Fell Fun

    Avaliação das tendências da produtividade agrícola para a cultura da soja no Brasil.

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    O Brasil é o segundo maior produtor mundial de soja. A sustentabilidade e o aumento da produção da soja deverão depender mais dos ganhos de produtividade do que da expansão da área cultivada nos próximos anos. Este trabalho teve como objetivo avaliar as tendências temporais da produtividade da soja no Brasil por meio de modelos estatísticos utilizando um banco de dados do Instituto Brasileiro de Geografia e Estatística (IBGE) (IBGE, 2016). Para tal foram aplicados sete métodos estatísticos às séries temporais de produtividade. O método que melhor se ajustou aos dados, menor erro quadrático médio, foi o método Loess Smoth

    Calibração e validação da produtividade agrícola municipal para cultura da soja na região sul do Brasil simuladas através do modelo Sarrazon.

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    Este trabalho apresenta três modelos estatísticos que visam estimar a produtividade real da cultura de soja na região Sul do País, com base nos valores do Índice de Satisfação da Necessidade de água (ISNA) gerados para o Zoneamento Agrícola de Risco Climático da soja. A fim de se avaliar a confiança dos métodos e como ferramenta de comparação entre eles, obtiveram-se os erros de estimativa destes com a produtividade observada

    Systematic versus on-demand early palliative care: A randomised clinical trial assessing quality of care and treatment aggressiveness near the end of life

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    Aim Early palliative care (EPC) in oncology has shown sparse evidence of a positive impact on patient outcomes, quality of care outcomes and costs. Patients and methods Data for this secondary analysis were taken from a trial of 207 outpatients with metastatic pancreatic cancer randomly assigned to receive standard cancer care plus on-demand EPC (standard arm) or standard cancer care plus systematic EPC (interventional arm). After 20 months\u2019 follow-up, 149 (80%) had died. Outcome measures were frequency, type and timing of chemotherapy administration, use of resources, place of death and overall survival. Results Some indices of end-of-life (EoL) aggressiveness had a favourable impact from systematic EPC. Interventional arm patients showed higher use of hospice services: a significantly longer median and mean period of hospice care (P = 0.025 for both indexes) and a significantly higher median and mean number of hospice admissions (both P < 0.010). In the experimental arm, chemotherapy was performed in the last 30 days of life in a significantly inferior rate with respect to control arm: 18.7% versus 27.8% (adjusted P = 0.036). Other non-significant differences were seen in favour of experimental arm. Conclusions Systematic EPC showed a significant impact on some indicators of EoL treatment aggressiveness. These data, reinforced by multiple non-significant differences in most of the other items, suggest that quality of care is improved by this approach. This study is registered on ClinicalTrials.gov (NCT01996540)

    Sonidegib as a Locally Advanced Basal Cell Carcinoma Therapy in Real-life Clinical Setting: A National Multicentre Study

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    Background: Basal cell carcinoma (BCC) is the most prevalent cancer. A minority of BCCs have an aggressive behaviour (laBCC) and may require hedgehog pathway inhibitors such as sonidegib as its treatment. Objective: To describe the use of sonidegib in a large number of patients and provide more data on its real-life efficacy and safety profile.Methods: We conducted a retrospective and multicentric study that included patients treated with sonidegib. Epidemiological, effectiveness and safety data were collected.Results: A total of 82 patients with a mean age of 73.9 years were included. Ten patients had Gorlin syndrome. Median treatment duration was 6 months. Median follow-up duration was 34.2 months. Globally, 81.7% of the patients showed clinical improvement (52.4% partial response and 29.3% complete response), 12.2% clinical stability and 6.1% disease progression. There was no statistically significant difference in clinical improvement between the 24 h and 48 h sonidegib posology. After 6 months of treatment, 48.8% of the patients discontinued sonidegib. Prior vismodegib treatment and recurrent primary BCC were associated with a poorer response to sonidegib. At 6 months of treatment, 68.3% of the patients experienced at least one adverse effect. Conclusion: Sonidegib shows good effectiveness and acceptable safety profile in usual clinical practice.& COPY; 2023 AEDV. Published by Elsevier Espan & SIM;a, S.L.U.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
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