Nominalismo, Voluntarismo y contingentismo

En este trabajo se revisan las tesis centrales del pensamiento de Ockham —representacionismo, voluntarismo, contingentismo— y la critica de L. Polo a las mismas. Se divide en tres partes: teoria del conocimiento, psicologia y ética, y metafísic

Severe Deoxygenation Event Caused by the 2011 Eruption of the Submarine Volcano Tagoro (El Hierro, Canary Islands)

The shallow, near-shore submarine volcano Tagoro erupted in October 2011 at the Mar de las Calmas marine reserve, south of El Hierro island. The injection of lava into the ocean had its strongest episode during November 2011 and lasted until March 2012. During this time, in situ measurements of dissolved oxygen were carried out, using a continuous oxygen sensor constantly calibrated with water samples. A severe deoxygenation was observed in the area, particularly during October-November 2011, which was one of the main causes of the high mortality observed among the local marine ecosystem. The measured O2 concentrations were as low as 7.71 µmol kg-1, which represents a -96% decrease with respect to unaffected waters. The oxygen depletion was found in the first 250 m of the water column, with peaks between 70-120 m depth. The deoxygenated plume covered an area of at least 464 km2, distributed particularly south and south-west of the volcano, with occasional patches found north of the island. The oxygen levels were also monitored through the following years, during the degassing stage of the volcano, when oxygen depletion was no longer observed. Additionally, during the eruption, an island-generated anticyclonic eddy interacted with the volcanic plume and transported it for at least 80 km, where the O2 measurements still showed a -8% decrease after mixing and dilution. This feature draws attention to the permanence and transport of volcanic plumes far away from their source and long after the emission.En prens

The natural ocean acidification and fertilization event caused by the submarine eruption of El Hierro

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Importance of N2 fixation vs. nitrate diffusion along a latitudinal transect in the Atlantic Ocean

We present ocean, basin-scale simultaneous measurements of N2-fixation, nitrate diffusion, and primary production along a south–north transect in the Atlantic Ocean crossing three biogeographic provinces: the south subtropical Atlantic (SSA; , 31uS–12uS), the equatorial Atlantic (EA; , 12uS–16uN), and the north subtropical Atlantic (NSA, , 16uN–9uN) in April–May 2008. N2-fixation and primary production were measured as 15N2 and 14C uptake, respectively. Dissipation rates of turbulent kinetic energy (e) were measured with a microstructure profiler. The vertical input of nitrate through eddy diffusion was calculated from the product of diffusivity, derived from e, and the gradient of nanomolar nitrate concentration across the base of the euphotic zone. The mean N2-fixation rate in EA was 56 6 49 mmol N m22 d21, whereas SSA and NSA had much lower values (, 10 mmol N m22 d21). Because of the large spatial variability in nitrate diffusion (34 6 50, 405 6 888, and 844 6 1258 mmol N m22 d21 in SSA, EA, and NSA, respectively), the contribution of N2-fixation to new production in the SSA, EA, and NSA was 44% 6 30%, 22% 6 19%, and 2% 6 2%, respectively. The differences between SSA and NSA in the contribution of N2 fixation were partly due to the contrasting seasonal forcing in each hemisphere, which likely affected both N2 fixation rates and vertical nitrate diffusion. The variability in the nitrogen budget of the Atlantic subtropical gyres was unexpectedly high and largely uncoupled from relatively constant phytoplankton standing stocks and primary production rates.CTM2004-05174-C02 CTM2007-28295-E/MAR Programa I. Parga-Ponda

Synchronization and resonance in a driven system of coupled oscillators

We study the noise effects in a driven system of globally coupled oscillators, with particular attention to the interplay between driving and noise. The self-consistency equation for the order parameter, which measures the collective synchronization of the system, is derived; it is found that the total order parameter decreases monotonically with noise, indicating overall suppression of synchronization. Still, for large coupling strengths, there exists an optimal noise level at which the periodic (ac) component of the order parameter reaches its maximum. The response of the phase velocity is also examined and found to display resonance behavior.Comment: 17 pages, 3 figure

Modified differentials and basic cohomology for Riemannian foliations

We define a new version of the exterior derivative on the basic forms of a Riemannian foliation to obtain a new form of basic cohomology that satisfies Poincar\'e duality in the transversally orientable case. We use this twisted basic cohomology to show relationships between curvature, tautness, and vanishing of the basic Euler characteristic and basic signature.Comment: 20 pages, references added, minor corrections mad

Phase synchronization and noise-induced resonance in systems of coupled oscillators

We study synchronization and noise-induced resonance phenomena in systems of globally coupled oscillators, each possessing finite inertia. The behavior of the order parameter, which measures collective synchronization of the system, is investigated as the noise level and the coupling strength are varied, and hysteretic behavior is manifested. The power spectrum of the phase velocity is also examined and the quality factor as well as the response function is obtained to reveal noise-induced resonance behavior.Comment: to be published in Phys. Rev.

Economic Valuation of Health Care Services in Public Health Systems: A Study about Willingness to Pay (WTP) for Nursing Consultations

Background: Identifying the economic value assigned by users to a particular health service is of principal interest in planning the service. The aim of this study was to evaluate the perception of economic value of nursing consultation in primary care (PC) by its users. Methods and Results: Economic study using contingent valuation methodology. A total of 662 users of nursing consultation from 23 health centers were included. Data on demographic and socioeconomic characteristics, health needs, pattern of usage, and satisfaction with provided service were compiled. The validity of the response was evaluated by an explanatory mixed-effects multilevel model in order to assess the factors associated with the response according to the welfare theory. Response reliability was also evaluated. Subjects included in the study indicated an average Willingness to Pay (WTP) of €14.4 (CI 95%: €13.2–15.5; median €10) and an average Willingness to Accept [Compensation] (WTA) of €20.9 (CI 95%: €19.6–22.2; median €20). Average area income, personal income, consultation duration, home visit, and education level correlated with greater WTP. Women and older subjects showed lower WTP. Fixed parameters explained 8.41% of the residual variability, and response clustering in different health centers explained 4–6% of the total variability. The influence of income on WTP was different in each center. The responses for WTP and WTA in a subgroup of subjects were consistent when reassessed after 2 weeks (intraclass correlation coefficients 0.952 and 0.893, respectively). Conclusions: The economic value of nursing services provided within PC in a public health system is clearly perceived by its user. The perception of this value is influenced by socioeconomic and demographic characteristics of the subjects and their environment, and by the unique characteristics of the evaluated service. The method of contingent valuation is useful for making explicit this perception of value of health services

Determination of bioactive compounds and physicochemical param-eters of honey produced in the state of Veracruz, Mexico

Veracruz occupies one of the first places as a producer of honey. However, there are few studies that address the typing of bioactive compounds and the physicochemical characteristics present in Veracruz honey. Objective: Determine the physicochemical and antioxidant parameters, and total phenols (TP) of Veracruz honey. Design/methodology/approach: Honey samples were collected at 17 sites in the state of Veracruz, and physicochemical, TP and antioxidant parameters were analyzed. Results: The determined physicochemical parameters presented values within the ranges set by NOM-004-SAG/GAN-2018 and the Codex Alimentarius. The color distribution showed the following values: dark (47.6%), amber (19.04%), white (19.04%), and the colors aqua white, light amber and extra light showed values of 4.77% each. Dark honeys presented ~370 μg GAE/mL, compared to the contents shown by light-colored honeys of ~200 μg GAE/mL. Sayula de Aleman honey had the highest antioxidant content with 143 mg TE/g honey. On the other hand, honey from San Pedro Soteapan showed the lowest contents (53 mg TE/g honey). Limitations on study/implications: The selection of Veracruz honey apiaries and lack of flora information. Findings/conclusions: The honeys presented physicochemical parameters within ranges of national standards. These Veracruz honeys exhibited a range of colors from dark to extra light. A positive correlation was shown between color and TP content. The antioxidant content was dependent on the botanical origin and color of these honeys.Veracruz occupies one of the first places as a producer of honey. However, there are few studies that address the typing of bioactive compounds, and the physicochemical characteristics present in Veracruz honey. Objective: Determine the physicochemical and antioxidant parameters, and total phenols (TP) of Veracruz honey. Design/methodology/approach: Honey samples were collected at 17 sites in the state of Veracruz, and physicochemical, TP and antioxidant parameters were analyzed. Results: The determined physicochemical parameters presented values within the ranges set by NOM-004-SAG/GAN-2018 and the Codex Alimentarius. The color distribution showed the following values: dark (47.6%), amber (19.04%), white (19.04%), and the colors aqua white, light amber and extra light showed values of 4.77% each. Dark honeys presented ~370 μg GAE/mL, compared to the contents shown by light-colored honeys of ~200 μg GAE/mL. Sayula de Aleman honey had the highest antioxidant content with 143 mg TE/g honey. On the other hand, honey from San Pedro Soteapan showed the lowest contents (53 mg TE/g honey). Limitations on study/implications: The selection of Veracruz honey apiaries and lack of flora information. Findings/conclusions: The honeys presented physicochemical parameters within ranges of national standards. These Veracruz honeys exhibited a range of colors from dark to extra light. A positive correlation was shown between color and TP content. The antioxidant content was dependent on the botanical origin and color of these honeys.

Field Measurements of Terrestrial and Martian Dust Devils

Surface-based measurements of terrestrial and martian dust devils/convective vortices provided from mobile and stationary platforms are discussed. Imaging of terrestrial dust devils has quantified their rotational and vertical wind speeds, translation speeds, dimensions, dust load, and frequency of occurrence. Imaging of martian dust devils has provided translation speeds and constraints on dimensions, but only limited constraints on vertical motion within a vortex. The longer mission durations on Mars afforded by long operating robotic landers and rovers have provided statistical quantification of vortex occurrence (time-of-sol, and recently seasonal) that has until recently not been a primary outcome of more temporally limited terrestrial dust devil measurement campaigns. Terrestrial measurement campaigns have included a more extensive range of measured vortex parameters (pressure, wind, morphology, etc.) than have martian opportunities, with electric field and direct measure of dust abundance not yet obtained on Mars. No martian robotic mission has yet provided contemporaneous high frequency wind and pressure measurements. Comparison of measured terrestrial and martian dust devil characteristics suggests that martian dust devils are larger and possess faster maximum rotational wind speeds, that the absolute magnitude of the pressure deficit within a terrestrial dust devil is an order of magnitude greater than a martian dust devil, and that the time-of-day variation in vortex frequency is similar. Recent terrestrial investigations have demonstrated the presence of diagnostic dust devil signals within seismic and infrasound measurements; an upcoming Mars robotic mission will obtain similar measurement types