43 research outputs found

    Linkages between mineralogy, fluid chemistry, and microbial communities within hydrothermal chimneys from the Endeavor Segment, Juan de Fuca Ridge

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    Rock and fluid samples were collected from three hydrothermal chimneys at the Endeavour Segment, Juan de Fuca Ridge to evaluate linkages among mineralogy, fluid chemistry, and microbial community composition within the chimneys. Mössbauer, midinfrared thermal emission, and visible-near infrared spectroscopies were utilized for the first time to characterize vent mineralogy, in addition to thin-section petrography, X-ray diffraction, and elemental analyses. A 282°C venting chimney from the Bastille edifice was composed primarily of sulfide minerals such as chalcopyrite, marcasite, and sphalerite. In contrast, samples from a 300°C venting chimney from the Dante edifice and a 321°C venting chimney from the Hot Harold edifice contained a high abundance of the sulfate mineral anhydrite. Geochemical modeling of mixed vent fluids suggested the oxic-anoxic transition zone was above 100°C at all three vents, and that the thermodynamic energy available for autotrophic microbial redox reactions favored aerobic sulfide and methane oxidation. As predicted, microbes within the Dante and Hot Harold chimneys were most closely related to mesophilic and thermophilic aerobes of the Betaproteobacteria and Gammaproteobacteria and sulfide-oxidizing autotrophic Epsilonproteobacteria. However, most of the microbes within the Bastille chimney were most closely related to mesophilic and thermophilic anaerobes of the Deltaproteobacteria, especially sulfate reducers, and anaerobic hyperthermophilic archaea. The predominance of anaerobes in the Bastille chimney indicated that other environmental factors promote anoxic conditions. Possibilities include the maturity or fluid flow characteristics of the chimney, abiotic Fe2+ and S2− oxidation in the vent fluids, or O2 depletion by aerobic respiration on the chimney outer wall

    Robot-assisted surgery for women with endometrial cancer: Surgical and oncologic outcomes within a Belgium gynaecological oncology group cohort.

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    peer reviewed[en] OBJECTIVE: To evaluate surgical and oncologic outcomes of patients treated by robot-assisted surgery for endometrial cancer within the Belgium Gynaecological Oncology Group (BGOG). STUDY DESIGN: We performed a retrospective analysis of women with clinically Stage I endometrial cancer who underwent surgical treatment from 2007 to 2018 in five institutions of the BGOG group. RESULTS: A total of 598 consecutive women were identified. The rate of conversion to laparotomy was low (0.8%). The mean postoperative Complication Common Comprehensive Index (CCI) score was 3.4. The rate of perioperative complications did not differ between age groups, however the disease-free survival was significantly lower in patients over 75 years compared to patients under 65 years of age (p=0.008). Per-operative complications, conversion to laparotomy rate, post-operative hospital stay, CCI score and disease-free survival were not impacted by increasing BMI. CONCLUSION: Robot-assisted surgery for the surgical treatment of patients suffering from early-stage endometrial cancer is associated with favourable surgical and oncologic outcomes, particularly for unfavourable groups such as elderly and obese women, thus permitting a low morbidity minimally-invasive surgical approach for the majority of patients in expert centres

    Individual Rights, Economic Transactions, and Recognition: A Legal Approach to Social Economics

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    Modernity brought the idea of individual property rights as a com- plex phenomenon. However, economics adopted a simplistic view of property as a fundamental institution, understating the complex interaction of different rights and obligations that frame the legal environment of economic processes with an insufficiently elaborated tool. Here, a more elaborate view of legal elements will be propose

    Properties of field functionals and characterization of local functionals

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    Functionals (i.e. functions of functions) are widely used in quantum field theory and solid-state physics. In this paper, functionals are given a rigorous mathematical framework and their main properties are described. The choice of the proper space of test functions (smooth functions) and of the relevant concept of differential (Bastiani differential) are discussed. The relation between the multiple derivatives of a functional and the corresponding distributions is described in detail. It is proved that, in a neighborhood of every test function, the support of a smooth functional is uniformly compactly supported and the order of the corresponding distribution is uniformly bounded. Relying on a recent work by Yoann Dabrowski, several spaces of functionals are furnished with a complete and nuclear topology. In view of physical applications, it is shown that most formal manipulations can be given a rigorous meaning. A new concept of local functionals is proposed and two characterizations of them are given: the first one uses the additivity (or Hammerstein) property, the second one is a variant of Peetre's theorem. Finally, the first step of a cohomological approach to quantum field theory is carried out by proving a global Poincar\'e lemma and defining multi-vector fields and graded functionals within our framework.Comment: 32 pages, no figur

    Moral Sentiments, Institutions, and Civil Society: Exploiting Family Resemblances between Smith and Hegel to Resolve Some Conceptual Issues in Sen’s Recent Contributions to the Theory of Justice

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    In his Idea of Justice, Amartya Sen compares the two basic approaches to evaluate institutions, transcendental institutionalism and realization-focused comparisons. Referring to Smith's Impartial Spectator, he argues in favour of the latter and proposes the principle of Open Impartiality. However, this cannot solve the tension between universalism and contextualization of values that Sen therefore inherits from Smith. Based on recent Hegel scholarship, we argue that some of the difficulties can be resolved, considering the role Smith played in the development of Hegel's thinking. Hegel's concept of recognition plays an essential role in establishing the possibility of impartiality both on the level of consciousness and on the level of institutional intersubjectivity. Hegel's critique of Kants formalist ethics (also considered as transcendental institutionalism by Sen), his analysis of the civil society in the Philosophy of Right, especially his focus on associations and estates, can serve as a model for making Sen's focus on public discourse theoretically more concise and pragmatically feasible. Hegel shows that universalistic attitudes can only emerge in specific institutional contexts

    The Normative Problem of Merit Goods in Perspective

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    In his Theory of Public Finance (1959), Musgrave invented the concept of merit wants to describe public wants that are satisfied by goods provided by the government in violation of the principle of consumer sovereignty. Starting from Musgrave’s mature discussion (1987), I construct two categories to classify the explanations of merit goods. The first strand of thought attempts to justify merit goods within the New welfare economics, by modifying its assumptions to accommodate irrationality, uncertainty, lack of information, and psychic externalities. The second category encompasses more radical departures from consumer sovereignty, drawn from philosophical critiques of economics. In the third part of the paper, I argue that the two strands might be represented by a non-individualistic social welfare function. I also show how this solution echoes Musgrave’s early views on public expenditures before he coined the concept of merit wants. From an historical perspective, the survival of the concept highlights the persistence of a social point of view in welfare economics

    The Decay of Greek Mathematics

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