94 research outputs found

    Symmetry defects in single-gyre, wind-driven oceanic systems

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    We explore some symmetry properties of the leading terms that constitute the solution describing the flow field structure in a wind-driven, bottom-dissipated ocean. Both the weakly non-linear and the highly non-linear regime are investigated. The main result is that the northward displacement and the westward intensification of the current system, which are typical of the subtropical gyres (for instance the North Atlantic Ocean), can be ascribed to an interplay between the symmetries of these terms. Moreover, a duality relationship allows us to relate the conclusions concerning one regime to the other

    Human aging and longevity are characterized by high levels of mitokines

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    Mitochondrial stress elicits the production of stress response molecules indicated as mitokines, including FGF21, GDF15 and Humanin (HN). Many diseases are characterized by progressive mitochondrial dysfunction with alterations of mitokine secretion. It is still controversial whether healthy aging and extreme longevity are accompanied by altered production of mitokines. We analyzed FGF21, HN and GDF15 plasma levels in 693 subjects aged from 21 to 113 years, and the association of these mitokines with parameters of health status. FGF21, HN and GDF15 resulted increased in old age, with the highest levels found in centenarians. These molecules are associated with worsened parameters (such as handgrip strength, insulin sensitivity, total triglycerides), particularly in 70-year-old persons, and their levels are inversely correlated with survival in the oldest subjects. Considering the positive biological effect of these molecules, our results can be interpreted in the framework of the hormetic paradigm as an attempt of the cells/tissues to cope with a stress that can have beneficial or detrimental effects depending on its intensity. Finally, persons with Down Syndrome (characterized by accelerated aging) have higher levels of GDF15 and HN with respect to their siblings, suggesting that these molecules, especially GDF15, could be considered markers of biological age

    Isotopic signature in isolated south-western populations of European brown bear (Ursus arctos)

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    Stable isotope analysis of animal tissue samples is increasingly used to study the trophic ecology of target species. The isotopic signatures respond to the type of diet, but also to the environmental conditions of their habitat. In the case of omnivorous, seasonal or opportunistic feeding species, the interpretation of isotopic values is more complex, as it is largely determined by food selection, either due to individual choice or because of availability. We analysed C and N isotopes in brown bear (Ursus arctos) hair from four isolated populations of south-western Europe (Cantabrian, Pyrenees, Central Apennines and Alpine) accounting for the geographical and climatic differences among the four areas. We found inter-population differences in isotopic signatures that cannot be attributed to climatic differences alone, indicating that at least some bears from relatively higher altitude populations experiencing higher precipitation (Pyrenees) show a greater consumption of animal foods than those from lower altitudes (Cantabrian and Apennines). The quantification of isotopic niche space using Layman's metrics identified significant similarities between the Cantabrian and Central Apennine samples that markedly differ from the Pyrenean and Alpine. Our study provides a baseline to allow further comparisons in isotopic niche spaces in a broad ranged omnivorous mammal, whose European distribution requires further conservation attention especially for southern isolated populations

    Phenotypic Changes Across a Geographic Gradient: The Case of Three Sympatric Dolphin Species

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    Phenotypic changes in the mammalian mandible can occur at different spatial and temporal scales. We investigated mandibular size and shape variation in three extant closely related dolphins (Cetacea, Odontoceti): Tursiops truncatus, Stenella coeruleoalba and Delphinus delphis in order to test the hypothesis that similar phenotypic changes occur across the same geographical gradient. Our data included 219 specimens representative of the following geographic locations: the Mediterranean Sea, the eastern north Atlantic and the North Sea. Each mandibula was photographed laterally and spatial positioning of eight homologous 2D landmarks was recorded. After applying generalised Procrustes analysis (GPA), intraspecific variation was first investigated between sexes and among populations to allow further pooling of samples. Size and shape differences among populations and species were investigated through multivariate ordination techniques (PCA), Procrustes ANOVA and allometric analyses. In all three species, Mediterranean populations clearly differed in mandible shape from the extra-Mediterranean ones. Among the three, the direction of geographic phenotypic changes was significantly similar in the striped and common dolphin, while the bottlenose dolphin was the most divergent species, differing both in size and allometric trajectory. Shape variation of the two former species highlighted a morphological convergence in the Atlantic, and a phenotypic divergence in the Mediterranean. Shape differences among the three dolphin species were interpreted in the light of different prey preferences, feeding strategies and habitat partitioning to avoid direct competition

    Short Telomere Length Is Related to Limitations in Physical Function in Elderly European Adults

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    The present study aims to explore the potential influence of leucocyte telomere length (LTL) on both a single indicator and a composite construct of physical functioning in a large European population of elderly men and women across diverse geographical locations. A total of 1,221 adults (65–79 years) were recruited from five European countries within the framework of NU-AGE study. The physical functioning construct was based on the 36-item Short Form Health Survey. Handgrip strength was used as a single indicator of muscle function and LTL was assessed using quantitative real-time PCR. Women had significantly longer (p < 0.05) LTL than men. Participants in Poland had significantly shorter LTL than in the other study centers, whereas participants in the Netherlands had significantly longer LTL than most of the other centers (p < 0.01). An analysis of LTL as a continuous outcome against physical functioning by using linear models revealed inconsistent findings. In contrast, based on an analysis of contrasting telomere lengths (first vs. fifth quintile of LTL), a significant odds ratio (OR) of 1.7 (95% CI: 1.1 – 2.6; p < 0.05) of having functional limitation was observed in those belonging to the first LTL quintile compared to the fifth. Interestingly, having the shortest LTL was still related to a higher likelihood of having physical limitation when compared to all remaining quintiles (OR: 1.5, 95% CI: 1.1 – 2.1; p < 0.05), even after adjustment by study center, age, sex, and overweight status. Collectively, our findings suggest that short LTL is an independent risk factor that accounts for functional decline in elderly European populations. The influence of LTL on functional limitation seems driven by the detrimental effect of having short telomeres rather than reflecting a linear dose-response relationship

    Surface wave tomography across Afar, Ethiopia: crustal structure at a rift triple-junction zone

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    The Afar Depression in northeast Africa contains the rift triple-junction between the Nubia, Arabia and Somalia plates. We analyze Rayleigh wave group velocity from 250 regional earthquakes recorded by 40 broadband stations to study the crustal structure across Afar and adjacent plateau regions in northern Ethiopia. The dispersion velocities are inverted to obtain surface wave tomographic maps for periods between 5 and 25 seconds, sensitive to approximately the top 30 km of the lithosphere. The tomographic maps show a significant low dispersion velocity anomaly (>20%) within the upper crust, below the site of recent dyke intrusions (2005–present) in the Dabbahu and Manda-Hararo magmatic segments. Similar low velocity regions are imaged where magma intrusion in the Afar crust has been inferred over the last decade from seismicity or volcanic eruptions. We invert two group velocity curves to compare the S-wave velocity structure of the crust within an active magmatic segment with that of adjacent areas; the active region has a low velocity zone (Vs ∼ 3.2 km/s), between about 6–12 km, which we infer to be due to the presence of partial melt within the lower crust

    Cross-sectional analysis of the correlation between daily nutrient intake assessed by 7-day food records and biomarkers of dietary intake among participants of the NU-AGE study

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    Methods for measuring diet composition and quantifying nutrient intake with sufficient validity are essential to study the association between nutrition and health outcomes and risk of diseases. 7-day food records provides a quantification of food actually and currently consumed and is interesting for its use in intervention studies to monitor diet in a short-term period and to guide participants toward changing their intakes. The objective of this study is to analyze the correlation/association between the daily intake of selected nutrients (collected by a 7-day food records plus a mineral/vitamin supplementation questionnaire) and estimates of energy expenditure as well as blood and urine biomarkers of dietary intakes in 1,140 healthy elderly subjects (65–79 years) at baseline of the NU-AGE intervention study (NCT01754012, clinicaltrials.gov). The results show that: the daily intake of energy correlated significantly with predicted total energy expenditure (pTEE) (ρ = 0.459, p < 0.001, and q < 0.001); protein intake correlated significantly with the ratio of 24 h urinary urea to creatinine excretion (ρ = 0.143 for total protein intake, ρ = 0.296 for animal protein intake, and ρ = 0.359 for protein intake/body weight, p < 0.001 and q < 0.001 for each correlation); vitamin B12 and folate intakes correlated significantly with their serum concentrations (ρ = 0.151 and ρ = 0.363, respectively; p < 0.001 and q < 0.001 for each correlation); sodium and potassium intakes correlated significantly with their 24 h urinary excretion (ρ = 0.298 and ρ = 0.123, respectively; p < 0.001 and q < 0.001 for each correlation); vitamin B12 and folate intakes were negatively associated with plasma homocysteine measure (p = 0.001 and p = 0.004, respectively); stratifying subjects by gender, the correlations between energy intake and pTEE and between potassium intake and its 24 h urinary excretion lost their significance in women. Even if the plasma and urinary levels of these nutrients depend on several factors, the significant correlations between daily reported intake of nutrients (protein, vitamin B12, folate, and sodium) and their blood/urinary markers confirmed that the 7-day food records (plus a supplementation questionnaire) provides reliable data to evaluate short-term current dietary intake in European elderly subjects and it can be exploited to guide and monitor NU-AGE participants through the shift of their diet according NU-AGE recommendations

    Isotopic signature in isolated south-western populations of European brown bear (Ursus arctos)

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    Abstract Stable isotope analysis of animal tissue samples is increasingly used to study the trophic ecology of target species. The isotopic signatures respond to the type of diet, but also to the environmental conditions of their habitat. In the case of omnivorous, seasonal or opportunistic feeding species, the interpretation of isotopic values is more complex, as it is largely determined by food selection, either due to individual choice or because of availability. We analysed C and N isotopes in brown bear (Ursus arctos) hair from four isolated populations of south-western Europe (Cantabrian, Pyrenees, Central Apennines and Alpine) accounting for the geographical and climatic differences among the four areas. We found inter-population differences in isotopic signatures that cannot be attributed to climatic differences alone, indicating that at least some bears from relatively higher altitude populations experiencing higher precipitation (Pyrenees) show a greater consumption of animal foods than those from lower altitudes (Cantabrian and Apennines). The quantification of isotopic niche space using Layman’s metrics identified significant similarities between the Cantabrian and Central Apennine samples that markedly differ from the Pyrenean and Alpine. Our study provides a baseline to allow further comparisons in isotopic niche spaces in a broad ranged omnivorous mammal, whose European distribution requires further conservation attention especially for southern isolated populations

    Production of biogas - a manner of manufacturing

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    Advertising is commonly criticised for being pervasive, offensive, manipulative, harmful and irresponsible. This thesis focuses on the subjective criticisms and complex issues related to taste, decency, morality and offence, particularly as applied to, and understood within, the public and non-profit contexts. It is positioned at the intersection of marketing communications, marketing ethics, and social and non-profit marketing and explores how shocking, offensive and/or controversial (SOC) advertising appeals are interpreted, regulated and contested, by divergent groups of people. The approach taken is inspired by stakeholder theory and its focus on ethical decision-making for the betterment of all stakeholders. A mixed methods research design was adopted, resulting in three studies and these are presented as three discrete articles. Article I maps the field of existing research into SOC advertising and identifies gaps in our knowledge by means of a systematic literature review. It offers a critical appraisal of the field by highlighting definitional tensions, limited interdisciplinary work and an overdependence on student samples, on quantitative analysis and on non-longitudinal methodologies. It then proposes a series of remedies to these shortcomings. The second and third papers continue this reparative work by conceptualising and analysing actual SOC advertising interpretations and contestations. Article II explores the interpretations and experiences of SOC advertising within the regulatory context by analysing evidence from complainants, advertisers and regulatory bodies. It then proposes and develops an interpretation of the implicit power dynamics through which their contradictory interests overlap. The methodology underpinning this chapter combines a thematic content analysis of a substantial archive of complaints submitted to the Advertising Standards Authority (ASA) with an interpretation of case adjudication reports influenced by the work of Michel Foucault. The findings suggest that the regulation of SOC advertising prioritises the interests of firms and advertisers by relegating the role of complainant to that of merely registering complaints. The focus of Article III moves from the regulatory framework to the complained-about advertisements themselves. It provides an innovative theoretical and methodological approach to analysing SOC advertisements, rooted in the classic Aristotelian notion of rhetorical appeals and figuration, by developing and analysing a carefully selected example in detail. The analysis reveals an implicit NFP sector-specific appeal to ethos and the importance of a complex appeal to pathos. Each of the papers offers a different level of analysis of the often-contradictory viewpoints represented by stakeholder groups involved in, or affected by, the use of SOC advertising tactics. These viewpoints include academics, general consumers, the vocal minority of complainants, the advertisers including the non-profit and public organisations and the advertising creatives, and the advertising regulator. Taken together, the papers amount to a thesis that makes an important contribution to debates about the appropriateness, ethics, and application of SOC themes, formats and imagery in social and non-profit advertising. By exploring the regulatory processes of the ASA, an exemplary advertising self-regulatory body, it further contributes to the discourse on self-regulatory practices and highlights an NFP sector-specific consequentialist approach that appears to stifle the voice of the offended complainant. On a practical level, this work has implications for advertising practitioners and advertising regulators who are involved in producing and regulating advertising that uses SOC tactics
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