1,721,124 research outputs found
Differences and similarities in inflammatory mechanisms between asthma and chronic obstructive pulmonary disease (COPD)
Get PDFAsthma and chronic obstructive pulmonary disease (COPD) are the two most common respiratory chronic diseases worldwide, which are increasing in prevalence and have an enormous impact on the lives of patients and their caregivers. Both diseases are characterized by chronic inflammation of the lung, but the nature of the inflammatory response differs between diseases and shows a high degree of heterogeneity within each disease, accounting for a large number of endotypes and phenotypes. During my PhD various lines of research have been explored either by the research group in Padova or in partnerships with both national and international colleagues. We performed two clinical “real life” studies on two large cohorts of adult asthmatics and patients with COPD followed at our Centre, observing the existence of multiple phenotypes and inflammatory endotypes of these two diseases. In adult asthmatics, we differentiated patients with early onset asthma (EOA) from late onset asthma (LOA). In EOA patients, we observed a crucial role of allergic rhinitis and eosinophilic inflammation on disease control and pulmonary function. Conversely, in patients with LOA, rhinitis was not linked to poor asthma control while obesity, associated with a neutrophilic profile, had a major impact. In the cohort of COPD patients we observed that blood lymphopenia was related to a more severe disease with a predominant emphysematous component, while high levels of neutrophils and monocytes were related to chronic bronchitis and bronchiectasis.
My main research field was the investigation of the immunopathology of asthma and its etiology at the beginning of the natural history of the disease. We performed a series of studies on a cohort of wheezing children who underwent bronchoscopy for clinical purposes in whom bronchial biopsies were available for research. We first observed that airway remodeling and inflammatory hallmarks of adult asthma are also present in preschool wheezing and that phenotypes and endotypes of asthma are already recognizable. In particular, we observed that basement membrane thickening, a putative sign of epithelial-mesenchymal activation, is a very early sign that may precede inflammation and predict asthma development. Furthermore, we highlighted the presence of the eosinophilic non-atopic (T2H-nA) endotype where type 2 inflammation is present in absence of atopy. In these patients we described the presence of innate lymphoid cells type 2 (ILC2) as major drivers of type 2 inflammation. Of note, ILC2 infiltration was associated with persistence of asthma in a longitudinal follow-up, while we observed a shift toward the development of atopy with growth. In subsequent analyses we investigated the effects of air pollution and viral infections on the pathological hallmarks of asthma. We observed a direct relationship linking type 2 inflammation to both outdoor air pollution exposure and antiviral innate immune response impairment hypothesizing a possible existence in asthma of a pathogenetic intersection between atopy, air pollution and viral infections. Finally, we also described in a cohort of COPD patients that underwent lung surgery a deranged interferon-response mediated by NK, whose impairment was related to increased disease severity. These observations complement those of a different study, in which we studied the involvement of innate lymphoid cells type 1 (ILC1). Finally, addressing the interaction between COPD and viral infections we investigated the risk factors for the development and severity of COVID-19 in patients with COPD. We reported that cardio-metabolic conditions were the main risk factors for development of COVID-19 in COPD patients. Emphysema and low DLCO, were related to a more severe disease and need for intensive care, remarking a possible relationship between COPD severity and impaired antiviral responses.Asthma and chronic obstructive pulmonary disease (COPD) are the two most common respiratory chronic diseases worldwide, which are increasing in prevalence and have an enormous impact on the lives of patients and their caregivers. Both diseases are characterized by chronic inflammation of the lung, but the nature of the inflammatory response differs between diseases and shows a high degree of heterogeneity within each disease, accounting for a large number of endotypes and phenotypes. During my PhD various lines of research have been explored either by the research group in Padova or in partnerships with both national and international colleagues. We performed two clinical “real life” studies on two large cohorts of adult asthmatics and patients with COPD followed at our Centre, observing the existence of multiple phenotypes and inflammatory endotypes of these two diseases. In adult asthmatics, we differentiated patients with early onset asthma (EOA) from late onset asthma (LOA). In EOA patients, we observed a crucial role of allergic rhinitis and eosinophilic inflammation on disease control and pulmonary function. Conversely, in patients with LOA, rhinitis was not linked to poor asthma control while obesity, associated with a neutrophilic profile, had a major impact. In the cohort of COPD patients we observed that blood lymphopenia was related to a more severe disease with a predominant emphysematous component, while high levels of neutrophils and monocytes were related to chronic bronchitis and bronchiectasis.
My main research field was the investigation of the immunopathology of asthma and its etiology at the beginning of the natural history of the disease. We performed a series of studies on a cohort of wheezing children who underwent bronchoscopy for clinical purposes in whom bronchial biopsies were available for research. We first observed that airway remodeling and inflammatory hallmarks of adult asthma are also present in preschool wheezing and that phenotypes and endotypes of asthma are already recognizable. In particular, we observed that basement membrane thickening, a putative sign of epithelial-mesenchymal activation, is a very early sign that may precede inflammation and predict asthma development. Furthermore, we highlighted the presence of the eosinophilic non-atopic (T2H-nA) endotype where type 2 inflammation is present in absence of atopy. In these patients we described the presence of innate lymphoid cells type 2 (ILC2) as major drivers of type 2 inflammation. Of note, ILC2 infiltration was associated with persistence of asthma in a longitudinal follow-up, while we observed a shift toward the development of atopy with growth. In subsequent analyses we investigated the effects of air pollution and viral infections on the pathological hallmarks of asthma. We observed a direct relationship linking type 2 inflammation to both outdoor air pollution exposure and antiviral innate immune response impairment hypothesizing a possible existence in asthma of a pathogenetic intersection between atopy, air pollution and viral infections. Finally, we also described in a cohort of COPD patients that underwent lung surgery a deranged interferon-response mediated by NK, whose impairment was related to increased disease severity. These observations complement those of a different study, in which we studied the involvement of innate lymphoid cells type 1 (ILC1). Finally, addressing the interaction between COPD and viral infections we investigated the risk factors for the development and severity of COVID-19 in patients with COPD. We reported that cardio-metabolic conditions were the main risk factors for development of COVID-19 in COPD patients. Emphysema and low DLCO, were related to a more severe disease and need for intensive care, remarking a possible relationship between COPD severity and impaired antiviral responses
Predictions for imaging and spectroscopic surveys of galaxies and Active Galactic Nuclei in the mid-/far-Infrared
Get PDFWhile continuum imaging data at far-infrared to sub-millimeter wavelengths have provided tight constraints on the population properties of dusty star-forming galaxies up to high redshifts, future space missions like the Space Infra-Red Telescope for Cosmology and Astrophysics (SPICA) and ground based facilities like the Atacama Large Millimeter/submillimeter Array (ALMA) and the Cerro Chajnantor Atacama Telescope (CCAT) will allow detailed investigations of their physical properties via their mid-/far-infrared line emission.
The goal of this thesis project was to carry out predictions for these spectroscopic surveys using both a phenomenological approach and physically grounded models. These predictions are useful to optimize the planning of the surveys.
In the first part of the work, I present updated predictions for the number counts and the redshift distributions of star-forming galaxies spectroscopically detectable by these future missions. These predictions exploit a recent upgrade of evolutionary models, that includes the effect of strong gravitational lensing, in the light of the most recent Herschel and South Pole Telescope (SPT) data. Moreover the relations between line and continuum infrared luminosity are re-assessed, considering also differences among source populations, with the support of extensive simulations that take into account dust obscuration. My reference model for the redshift dependent IR luminosity functions is the one worked out by Cai et al. (2013) based on a comprehensive hybrid approach combining a physical model for the progenitors of early-type galaxies with a phenomenological one for late-type galaxies. The derived line luminosity functions are found to be highly sensitive to the spread of the line to continuum luminosity ratios. Estimates of the expected numbers of detections per spectral line by the SpicA FAR infrared Instrument (SAFARI) and by CCAT surveys for different integration times per field of view at fixed total observing time are presented. Comparing with the earlier estimates by Spinoglio et al. (2012), I find, in the case of SPICA-SAFARI, differences within a factor of two in most cases, but occasionally much larger. More substantial differences are found for CCAT.
Thereafter I present new estimates of redshift-dependent luminosity functions of IR lines detectable by SPICA-SAFARI and excited both by star formation and by AGN activity. The new estimates improve over previous work by dealing in a self consistent way with the emission of galaxies as a whole, including both the starburst and the AGN component. While the galaxy-AGN co-evolution was already worked out by Cai et al. (2013) in the case of proto-spheroidal galaxies, the evolution of late-type galaxies was dealt with independently of that of AGNs associated with them. I upgraded the model to enable it to take into account in a coherent way the contributions of both starbursts and AGNs to the IR emission during the cosmic evolution also of late-type galaxies.
New relationships between line and AGN bolometric luminosity have been derived and those between line and IR luminosities of the starburst component have been updated. These ingredients were used to work out predictions for the source counts in 11 mid/far-IR emission lines partially or entirely excited by AGN activity. I find that the statistics of the emission line detection of galaxies as a whole is mainly determined by the star formation rate, because of the rarity of bright AGNs. I also find that the slope of the line integral number counts is flatter than 2 implying that the number of detections at fixed observing time increases more by extending the survey area than by going deeper. I thus propose a spectroscopic survey of 1 hour integration per field-of-view over an area of 5 deg^2 to detect (at 5σ) ~760 AGNs in [OIV]25.89 μm - the brightest AGN mid-infrared line - out to z~2. Pointed observations of strongly lensed or hyper-luminous galaxies previously detected by large area surveys such as those by Herschel and by SPT can provide key information on the galaxy-AGN co-evolution out to higher redshifts.
Finally, as third step of the work, I present predictions for number counts and redshift distributions of galaxies detectable in continuum and in emission lines with the Mid-infrared (MIR) Instrument (SMI) proposed for SPICA. I have considered 24 MIR emission fine-structure lines, four Polycyclic Aromatic Hydrocarbon (PAH) bands (at 6.2, 7.7, 8.6 and 11.3 μm) and two silicate bands (in emission and in absorption) at 9.7 μm and 18.0 μm. Six of these lines are primarily associated with Active Galactic Nuclei (AGNs), the others primarily with star formation. Altogether, they allow us to study the interplay between star formation and super-massive black hole growth. A survey with the SMI spectrometers of 1 hour integration per field-of-view (FoV) over an area of 1 deg^2 will yield 5σ detections of ~140 AGN lines, produced by ~110 AGNs, and of ~5.2x10^4 star-forming galaxies, ~1.6x10^4 of which will be detected in at least two lines. The combination of a shallow (20.0 deg^2, 1.4x10^(-1) h integration per FoV) and a deep survey (6.9x10^(-3) deg^2, 635 h integration time), with the SMI camera, for a total of ~1000 h,
will accurately determine the MIR number counts of galaxies and of AGNs over five orders of magnitude in flux density, reaching values more than one order of magnitude fainter than the Spitzer 24 μm surveys. This will allow us to resolve almost completely the extragalactic background and to determine the cosmic star formation rate (SFR) function down to SFRs more than 100 times fainter than reached by the Herschel Observatory.
These spectroscopic observations will allow us to probe all phases of the interstellar medium (ionized, atomic and molecular). Measurements of these lines will provide redshifts and key insight on physical conditions of dust obscured regions and on the energy sources controlling their temperature and pressure. This information is critically important for investigating the complex physics ruling the dust-enshrouded active star-forming phase of galaxy evolution and the relationship with nuclear activity. Observations of strongly gravitationally lensed galaxies will be of special interest, because strong lensing allows us to measure the gas/dust distribution in galaxies up to high-z and to gain information on sources too faint to be detected with current instrument sensitivities, thus testing models for galaxy formation and dark matter
Editorial: Wellbeing and adherence to physical activity: What are the factors of the wellbeing concept leading to exercise adherence?
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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