155 research outputs found

    The Chapel Island Formation of Newfoundland (Canada) revisited: integrating ichnologic and sedimentologic datasets to unravel early metazoan evolution

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    The Chapel Island Formation (CIF) is a 1000+ m-thick, mainly siliciclastic succession that is well exposed along the coastline of Burin Peninsula, southeastern Newfoundland, eastern Canada. The CIF contains an outstanding record of latest Ediacaran-early Cambrian trace fossils with some intervals rich in small shelly fossils, and in 1992 the Fortune Head section was ratified by the International Commission on Stratigraphy (ICS) and the International Union of Geological Sciences (IUGS) as the Global Stratotype Section and Point (GSSP) for the Cambrian System. This was the first system-level GSSP defined primarily on the basis of trace fossils, a decision that evoked considerable discussion among the geological community. This thesis represents the first modern study of the sedimentology and the first taxonomic appraisal of the trace fossils since the original studies that proposed the GSSP in the 1980’s. More than 1700 m of CIF strata were logged in the sea cliffs of Burin Peninsula at Fortune Head, Fortune North, Grand Bank Head, Lewin’s Cove, Little Dantzic Cove, and Point May. A revision of the sedimentology permitted the description and interpretation of fourteen sedimentary facies composing five facies association (FA), which are interpreted to be deposited in: (1) mud-flat, mixed-flat, sand-flat, and tide-dominated or -influenced embayments (FA-A); (2) middle and lower shoreface (FA-B); (3) offshore transition, upper offshore, and lower offshore (FA-C); (4) shelf (stricto sensu) (FA-D); and (5) carbonate subtidal and intertidal environments (FA-E). An extensive trace-fossil dataset was built from careful field observations and provided a comprehensive record of bioturbation intensity (1596 data points on vertical bioturbation, 1481 data points on bedding plane bioturbation) and of trace-fossil metrics (3162 data points on burrow width, 1473 data points on burrow depth). In addition, a comprehensive revision of the trace-fossil composition (3508 trace fossils identified) allowed the description of twenty-eight ichnogenera and fifty-one ichnospecies, which correspond to cf. Allocotichnus dyeri, Archaeonassa fossulata, Arenicolites aff. carbonaria, Arenicolites isp., Bergaueria perata, B. cf. radiata, Circulichnis ligusticus, C. montanus, Cochlichnus anguineus, C. luguanensis, Conichnus conicus, Cruziana problematica, Curvolithus multiplex, C. simplex, Curvolithus isp., Dendroidichnites aff. irregulare, Didymaulichnus miettensis, Dimorphichnus isp. A, Dimorphichnus isp. B, cf. Dimorphichnus isp., ?Diplocraterion isp., Gordia marina, Gyrolithes gyratus, G. scintillus, Halopoa imbricata, Helminthoidichnites tenuis, Helminthopsis abeli, H. hieroglyphica, H. tenuis, Monomorphichnus bilinearis, M. lineatus, M. needleiunm, Monomorphichnus isp., Palaeophycus annulatus, P. tubularis, Palaeophycus isp., Psammichnites gigas circularis, P. cf. saltensis, Rosselia socialis, Rusophycus avalonensis, Rusophycus isp. A, Rusophycus isp. B, Saerichnites kutscheri comb. nov., Teichichnus rectus, Torrowangea rosei, Treptichnus bifurcus, T. coronatum, T. pedum, T. pollardi, Trichichnus linearis, and Trichichnus isp. Sectioning and polishing of 47 lithic samples from throughout the CIF showed that the sediment mixed layer that characterizes modern oceans developed through a series of steps that took place in the early Cambrian rather than in the Silurian as previously advocated. The main evolutionary innovations took place in the offshore environment with three paleoecologic stages that comprised: (1) an Ediacaran matground ecology, with surficial and very shallow infaunal grazing organisms living on and within microbially bound seafloors; (2) a Fortunian matground/firmground ecology, with a burst in behavioural and anatomical innovations and the first evidence of colonization of the shallow-tier; and (3) a late Fortunian/Cambrian Age 2 mixground ecology, with the development of a shallow mixed layer and deeper discrete burrows of the transition layer. Evaluation of outcrop quality based on accessibility, lateral and vertical continuity of beds, stratigraphic completeness, and type of exposure, demonstrated that Fortune Head, Fortune North, Grand Bank Head, and Little Dantzic Cove represented the best suited section to perform trace-fossil analyses, whereas Lewin’s Cove and Point May suffered from exposure biases affecting their trace-fossil records. The Ediacaran-Cambrian boundary interval was also studied in detail at Fortune Head, Grand Bank Head, Lewin’s Cove, and Point May, and the base of the Cambrian was placed confidently at the first appearance of trace fossils of the Treptichnus pedum Ichno-Assemblage Zone. This study demonstrates that only through detailed, comprehensive, and integrative approaches, can research provide new empirical evidence that further unfold our understanding of the history of animal life on Earth

    Caractérisation mécanique in vivo des tissus mous : application à la peau humaine et la chéloïde

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    The development of keloids, benign tumors on human skin, is not exclusively due to biological or genetic factors. The presence of anatomical sites favorable to the appearance of these tumors, while others are lacking them, attests to the importance of the mechanical environment of the tissue. The thesis aims to address the problem of keloid growth by developing a patient-specific pipeline, SofTI, based on in vivo experimental measurements and numerical modeling. The objective is to prevent further propagation of keloidic scars via a medical containment solution by identifying optimal material parameters to quantify mechanical stress and map its privileged direction locally. Additionally, the research work introduces MARSAC methodology to characterize the anisotropy in an undamaged skin by estimating Langer's line and stiffness along and across it with an in vivo multi-axial annular suction experiment. The method was used to analyze intra-subject and subject-to-subject variability over a clinical trial.Le développement des chéloïdes, tumeurs bénignes sur la peau humaine, n'est pas exclusivement dû à des facteurs biologiques ou génétiques. La présence de sites anatomiques favorables à l'apparition de ces tumeurs, tandis que d'autres en manquent, atteste de l'importance de l'environnement mécanique du tissu. La thèse vise à résoudre le problème de la croissance des chéloïdes en développant une méthode patient-spécifique, SofTI, basée sur des mesures expérimentales in vivo et une modélisation numérique. L'objectif est de prévenir la propagation des cicatrices chéloïdiennes à l'aide d'une solution médicale de contention en identifiant les paramètres matériau optimaux pour quantifier les contraintes mécaniques et cartographier ses directions privilégiées localement. De plus, le travail de recherche présente la méthodologie MARSAC pour charactériser l'anisotropie dans la peau saine en identifiant la ligne de Langer et la raideur le long et à travers celle-ci partant d'une expérience d'aspiration annulaire multi-axiale in vivo. La méthode a été employée pour analyser la variabilité intra- et inter-sujets sur un essai clinique

    Screening, risk stratification, and management of atrial fibrillation

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    Atrial fibrillation (AF), the most common sustained arrhythmia, is associated with high morbidity and mortality. Major improvements have been made in the diagnosis and management of AF in the past two decades. However, important questions pertaining to the screening, prognosis, risk stratification, and management of AF remain unanswered. This thesis presents original studies addressing knowledge gaps in these aspects of AF. In Chapter 2, using a large cohort of individuals from the UK Biobank, we investigated the association between lung function and incident AF. We observed that reduced ventilatory function was associated with increased risk of AF independently of age, sex, smoking, and several other known AF risk factors. This suggests that individuals with substantial reduction of their lung function might represent an appropriate population for targeted AF screening and ventilatory parameters might improve AF risk prediction. Chapter 3 assesses data related to implantable cardiac monitors (ICM). The first section reports AF diagnostic yield in a real-world cohort of patients receiving prolonged cardiac monitoring with ICM for stroke and unexplained syncope. It indicates that patients with stroke or transient ischemic attack (TIA) have a higher rate of AF detection compared with patients with unexplained syncope. However, this real-world study shows AF detection rates following stroke significantly lower than what has been previously reported. The second section of this chapter summarizes data on AF detection rates across different rhythm monitoring strategies (non-invasive and ICM) in patients with cryptogenic stroke (CS) or embolic stroke of undetermined source (ESUS). It shows that the yield of ICM increases with the duration of monitoring; more than a quarter of patients with CS or ESUS will be diagnosed with AF during follow-up. About one in seven patients have AF detected within a month of mobile cardiac outpatient telemetry, suggesting that a non-invasive rhythm monitoring strategy should be considered before invasive monitoring. Chapters 4 and 5 address risk stratification in patients with AF. Chapter 4 has two sections. The first section is a meta-analysis that comprehensively summarizes data from prospective cohort studies on clinical predictors of stroke in anticoagulant-naïve patients with AF. It shows that although weighted similarly in most risk stratification schemes such as the CHA2DS2-VASc score, the absolute risk of stroke attributable to hypertension, diabetes, vascular disease, and heart failure may not be the same in individual patients. Furthermore, it shows that female sex seems not to be universally associated with stroke or systemic embolism, suggesting that the decision to initiate oral anticoagulation should not be made on the sole basis of female sex as currently recommended by some scientific societies. By compiling evidence from various studies, the second section of this chapter demonstrates that some anatomic and functional cardiac imaging parameters are associated with stroke in patients with AF and therefore, might improve stroke risk stratification in these patients. Chapter 5 presents two systematic reviews and meta-analysis which show that AF and carotid artery disease frequently co-exist, with about one in ten patients with AF who has carotid stenosis, and vice versa; and non-stenotic carotid disease being much more frequent. Moreover, there is an association between carotid atherosclerosis and the risk of stroke in patients with AF, suggesting that the incorporation of carotid atherosclerosis and characteristics of carotid plaques into scoring systems might improve stroke prediction in patients with AF. Taking this further, the last section of this chapter investigates the potential added value of high-risk carotid plaques on stroke risk stratification compared to the classical CHA₂DS₂-VASc score in a prospective cohort of patients with AF. It shows a low prevalence (5.5%) of moderate to severe carotid stenosis (≥ 50%), whereas one in three participants have carotid plaques considered vulnerable or high-risk. Neither the degree of carotid stenosis nor the presence of vulnerable plaques is associated with incident ischemic stroke, suggesting that carotid disease is probably not an important cause of ischemic stroke in this group of patients with AF and therefore, vulnerable carotid plaques might not improve stroke risk stratification in patients with AF. Chapter 6 presents two pooled analyses of data on the prognostic impact of AF on acute coronary syndromes (ACS) and acute pulmonary embolism (aPE). The first section of the chapter shows that AF is common in patients with ACS (one in nine) and that it (especially newly diagnosed AF) is associated with poor short-term and long-term outcomes including re-infarction, heart failure, stroke, acute kidney injury, heart failure, major bleeding, and death. Likewise, the second section of the chapter demonstrates that AF is frequent in patients with aPE (one in eight) and is associated with increased short-term and long-term mortality. Considering this strong prognostic impact of AF in patients with ACS and aPE, its incorporation into risk stratification schemes for these patients should be considered. Furthermore, considering the significant incidence of AF in patients with ACS and aPE, studies are needed to determine the appropriate rhythm monitoring strategies in these patients. Chapters 7-9 focus on sex differences in the management of AF. Chapter 7 analyses data from 142 randomized controlled trials (RCTs) of AF published in top tiers cardiovascular journals and shows that despite recent progress, females remain substantially less represented in RCTs of AF. This raises concern about the generalizability of these trials and the validity of the evidence guiding the treatment of females. Furthermore, primary outcomes are infrequently reported by sex in these RCTs of AF. Considering established benefit of risk factor modification on outcomes in patients with AF, Chapter 8 assesses sex differences in weight-loss, cardiorespiratory fitness gain, and progression and recurrence of AF in patients undergoing aggressive risk factor modification. It shows that despite sex differences in some baseline characteristics, the benefits of weight-loss and fitness gain were favourable for both males and females. However, improvement in fitness had a much greater benefit for total arrhythmia freedom for females, whereas there was a trend towards more common regression from persistent to paroxysmal AF in males. These findings reinforce the need to address lifestyle risk factors to minimize arrhythmia recurrence and reduce symptom severity for all individuals. Finally, Chapter 9 investigates the impact of sex on the clinical profile, utilization of rhythm control therapies, in-hospital mortality, length of stay (LOS), and cost of hospitalization in patients admitted for AF in the United States. It shows similarities and disparities in risk factors for mortality between males and females, and that unlike what has been reported in several previous studies, although women had a relatively higher mortality rate, after risk adjustment, female sex was not a predictor of mortality.Thesis (Ph.D.) -- University of Adelaide, Adelaide Medical School, 02

    ATHENA Research Book, Volume 2

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    ATHENA European University is an association of nine higher education institutions with the mission of promoting excellence in research and innovation by enabling international cooperation. The acronym ATHENA stands for Association of Advanced Technologies in Higher Education. Partner institutions are from France, Germany, Greece, Italy, Lithuania, Portugal and Slovenia: University of Orléans, University of Siegen, Hellenic Mediterranean University, Niccolò Cusano University, Vilnius Gediminas Technical University, Polytechnic Institute of Porto and University of Maribor. In 2022, two institutions joined the alliance: the Maria Curie-Skłodowska University from Poland and the University of Vigo from Spain. Also in 2022, an institution from Austria joined the alliance as an associate member: Carinthia University of Applied Sciences. This research book presents a selection of the research activities of ATHENA University's partners. It contains an overview of the research activities of individual members, a selection of the most important bibliographic works of members, peer-reviewed student theses, a descriptive list of ATHENA lectures and reports from individual working sections of the ATHENA project. The ATHENA Research Book provides a platform that encourages collaborative and interdisciplinary research projects by advanced and early career researchers

    Geo-Information Technology and Its Applications

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    Geo-information technology has been playing an ever more important role in environmental monitoring, land resource quantification and mapping, geo-disaster damage and risk assessment, urban planning and smart city development. This book focuses on the fundamental and applied research in these domains, aiming to promote exchanges and communications, share the research outcomes of scientists worldwide and to put these achievements better social use. This Special Issue collects fourteen high-quality research papers and is expected to provide a useful reference and technical support for graduate students, scientists, civil engineers and experts of governments to valorize scientific research

    Chapter 34 - Biocompatibility of nanocellulose: Emerging biomedical applications

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    Nanocellulose already proved to be a highly relevant material for biomedical applications, ensued by its outstanding mechanical properties and, more importantly, its biocompatibility. Nevertheless, despite their previous intensive research, a notable number of emerging applications are still being developed. Interestingly, this drive is not solely based on the nanocellulose features, but also heavily dependent on sustainability. The three core nanocelluloses encompass cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs), and bacterial nanocellulose (BNC). All these different types of nanocellulose display highly interesting biomedical properties per se, after modification and when used in composite formulations. Novel applications that use nanocellulose includewell-known areas, namely, wound dressings, implants, indwelling medical devices, scaffolds, and novel printed scaffolds. Their cytotoxicity and biocompatibility using recent methodologies are thoroughly analyzed to reinforce their near future applicability. By analyzing the pristine core nanocellulose, none display cytotoxicity. However, CNF has the highest potential to fail long-term biocompatibility since it tends to trigger inflammation. On the other hand, neverdried BNC displays a remarkable biocompatibility. Despite this, all nanocelluloses clearly represent a flag bearer of future superior biomaterials, being elite materials in the urgent replacement of our petrochemical dependence

    Anais...

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    XVII ENFRUTE. Organização: Presidente, Dr. Henrique Belmonte Petry, EPAGRI - Estação Experimental de Urussanga, http://lattes.cnpq.br/4096205094079511 Vice-Presidente, Dr. Fernando José Hawerroth - EMBRAPA Uva e vinho, http://lattes.cnpq.br/3248468608375002 2º Vice-Presidente Dr. Leo Ruffato - UDESC - Universidade do Estado de Santa Catarina http://lattes.cnpq.br/2926951390021904 Tesoureiro Dr. André Luiz Kulkamp de Souza - EPAGRI - Estação Experimental de Videira http://lattes.cnpq.br/4503965477493383 2º Tesoureiro M.Sc. Nelson Pires Feldberg EMBRAPA CLIMA TEMPERADO - Estação Experimental Canoinhas http://lattes.cnpq.br/4503965477493383 Secretário Dr. Gustavo Henrique Ferrero Klabunde EPAGRI - Estação Experimental de Itajaí http://lattes.cnpq.br/0472136300460695 2°Secretário Dr. Rafael Roveri Sabião EPAGRI - Centro de pesquisa para a agricultura familiar http://lattes.cnpq.br/3129472295751755 Presidente do Comitê Técnico Científico Dr. Alberto Fontanella Brighenti UFSC - Universidade Federal de Santa Catarina http://lattes.cnpq.br/539006944432239

    Stinging the Predators: A collection of papers that should never have been published

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    This ebook collects academic papers and conference abstracts that were meant to be so terrible that nobody in their right mind would publish them. All were submitted to journals and conferences to expose weak or non-existent peer review and other exploitative practices. Each paper has a brief introduction. Short essays round out the collection
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