8,392 research outputs found

    The expression of pre- and postcopulatory sexually selected traits reflects levels of dietary stress in guppies

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    Environmental and ecological conditions can shape the evolution of life history traits in many animals. Among such factors, food or nutrition availability can play an important evolutionary role in moderating an animal\u27s life history traits, particularly sexually selected traits. Here, we test whether diet quantity and/or composition in the form of omega-3 long chain polyunsaturated fatty acids (here termed \u27n3LC\u27) influence the expression of pre- and postcopulatory traits in the guppy (Poecilia reticulata), a livebearing poeciliid fish. We assigned males haphazardly to one of two experimental diets supplemented with n3LC, and each of these diet treatments was further divided into two diet \u27quantity\u27 treatments. Our experimental design therefore explored the main and interacting effects of two factors (n3LC content and diet quantity) on the expression of precopulatory (sexual behaviour and sexual ornamentation, including the size, number and spectral properties of colour spots) and postcopulatory (the velocity, viability, number and length of sperm) sexually selected traits. Our study revealed that diet quantity had significant effects on most of the pre- and postcopulatory traits, while n3LC manipulation had a significant effect on sperm traits and in particular on sperm viability. Our analyses also revealed interacting effects of diet quantity and n3LC levels on courtship displays, and the area of orange and iridescent colour spots in the males\u27 colour patterns. We also confirmed that our dietary manipulations of n3LC resulted in the differential uptake of n3LC in body and testes tissues in the different n3LC groups. This study reveals the effects of diet quantity and n3LC on behavioural, ornamental and ejaculate traits in P. reticulata and underscores the likely role that diet plays in maintaining the high variability in these condition-dependent sexual traits

    Using simple sequence repeats in 9 brassica complex species to assess hypertrophic curd induction

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    Five Simple Sequence Repeats (SSRs) were used to assess the relationship between inflorescence characteristics and their allelic variation in 53 Brassica oleracea and Brassica wild relatives (n = 9). Curd morphometric traits, such as weight (CW), height (CH), diameter (CD1), shape (CS) inflorescence curvature angle (CA), and its curd stem diameter (CD2), were measured. The aim of the work was to analyze the relationships among the allelic patterns of the SSRs primers utilized, and their status of homo or heterozygosity registered at each locus, as well as the inflorescence morphometric traits in order to individuate genomic regions stimulating the hypertrophy of this reproductive organ. The relationships found explain the diversity among B. oleracea complex species (n = 9) for the inflorescence size and structure, allowing important time reduction during the breeding process by crossing wild species, transferring useful resistance, and organoleptic and nutraceutical traits. The five SSRs loci were BoABI1, BoAP1, BoPLD1, BoTHL1, and PBCGSSRBo39. According to the allelic variation ascertained, we evaluated the heterozygosity index (H) for each SSR above cited. The results showed a significant interaction between the H index of the BoPLD1 gene and the inflorescence characteristics, summarized by the First Principal Component (PC1) (p-value = 0.0244); we ascertained a negative correlation between the H index and inflorescence characteristics, namely CW, CH, CD1, CD2, CA. The homozygosity BoPLD1 alelles, indicated by the H index, affect the inflorescence characteristics and broccoli and cauliflower yields

    The Tor Caldara CO2 Diffuse Degassing Structure (DDS): 222Rn/220Rn output before and after the August, 22, 2005 Anzio Earthquake (Mw=4.6).

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    Soon after a 222Rn and 220Rn survey in soil gases, performed (June 2005) in the frame of the Diffuse Degassing in Italy risk assessment project, a moderate earthquake (Mw=4.6) occurred in the Anzio offshore, on August, 22, 2005, only 5 miles from the Tor Caldara Diffuse Degassing Structure (DDS onward). Having available the pre-earthquake 222Rn and 220Rn grid-map on around 50 soil-gas points and being 222Rn both a stress-pathfinder and a discriminative component of activated-faults, a mirrorlike survey was repeated on the same 50 sites, soon after the close earthquake. Later, during a quiescent-aseismic period (December, 2005), a CO2 flux survey was performed for the same 50 sites, adding detailed measurements (more than 100 sites) for the highest flux sectors. The aim of this survey was both to have an overall picture of the background CO2 flux and to calculate the total budget of CO2 flux throughout the DDS, to better interpret the 222Rn and 220Rn areal surveys before and after the seismic event. Herewith, we distinguish the contribution of organic, diffusive and advective CO2 flux. Hints of convection and strong degassing linked to the fracture field, inside the DDS, have been envisaged on selected points, where continuous monitoring stations could be strategic, for seismic, volcanic and NGH surveillance. Despite we found higher 222Rn values in soils after the earthquake, suggesting an enhanced local degassing probably linked to a stress signal throughout the DDS as a whole, the results highlight an unmodified shape and location of the 222Rn anomalies before and after the earthquake. This evidence excludes both that the activated seismogenic segment has affected in some ways both the DDS degassing patterns and that fracture field changed. A similar result could be expected if the activated fault was oriented along the DDS itself and reached the surface. This evidence is well correlated with the reconstructed focal mechanism of the earthquake, pertaining to the transfer structure of the Ardea Graben , located along a peripheral sector of the degassing Alban Hills volcano and intersecting the DDS Tor Caldara itself. The shape and location of 222Rn anomalies inside the DDS for both the surveys are strictly inversely correlated with the areal CO2 flux data. The geometry of the degassing pathways is probably linked to the barrier action (sealing power) of the clays cropping out in the study area. These clays are generated by the strong leaching of the outcropping sedimentary Pleistocene rocks due to the huge flux of volcanic gas -rich fluids

    The Specific Heat of a Ferromagnetic Film.

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    We analyze the specific heat for the O(N)O(N) vector model on a dd-dimensional film geometry of thickness LL using ``environmentally friendly'' renormalization. We consider periodic, Dirichlet and antiperiodic boundary conditions, deriving expressions for the specific heat and an effective specific heat exponent, \alpha\ef. In the case of d=3d=3, for N=1N=1, by matching to the exact exponent of the two dimensional Ising model we capture the crossover for \xi_L\ra\infty between power law behaviour in the limit {L\over\xi_L}\ra\infty and logarithmic behaviour in the limit {L\over\xi_L}\ra0 for fixed LL, where ÎľL\xi_L is the correlation length in the transverse dimensions.Comment: 21 pages of Plain TeX. Postscript figures available upon request from [email protected]

    Do the omeprazole family compounds exert a protective effect against influenza-like illness?

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    BACKGROUND: Infections by influenza viruses place a heavy burden on public health and economies worldwide. Although vaccines are the best weapons against influenza, antiviral drugs could offer an opportunity to alleviate the burden of influenza. Since omeprazole family compounds block the “proton pump”, we hypothesized that they could interfere with the mechanism of fusion of the virus envelope and endosomal membrane, thereby hindering the M2 proton pump mechanism of influenza viruses. METHODS: A matched case-control study was performed in 2010-2011 in Italy. Cases were subjects aged over 18 years with a diagnosis of Influenza-like Illness (ILI); 254 case-control pairs were recruited. A multivariable conditional logistic regression analysis was used to assess the association between the prevention of ILI and the administration of omeprazole family compounds. The interaction between omeprazole family compounds and influenza vaccination was also examined. RESULTS: After control for potential confounders, subjects treated with omeprazole family compounds displayed a lower risk of catching ILI (OR(adj) = 0.29, 95% CI: 0.15-0.52). The risk of ILI in unvaccinated non-OFC users was about six times than that in vaccinated OFC users. CONCLUSIONS: Although confirmation is necessary, these results suggest that omeprazole family compounds could be profitably used in the prevention of ILI

    Resilience, Cardiological Outcome, and Their Correlations With Anxious-Depressive Symptoms and Quality of Life in Patients With an Implantable Cardioverter Defibrillator

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    Background: Resilience is proven as a protective factor against the development of psychiatric disorders, and it has gained clinical relevance in the development and progression of cardiovascular pathology. The authors performed a longitudinal study on patients with implantable cardioverter defibrillator (ICD) with the primary aim to highlight the possible existence of a correlation between individual resilience capacity, depressive and anxiety symptoms, and quality of life in terms of outcomes. The secondary aim was to analyze the differences between patients with major cardiac events in the follow-up and patients without cardiac events with respect to the previous variables. Materials and Methods: A total of 80 patients enrolled in the Cardiology Unit were evaluated at T0 and during the follow-up through the following scales: the 14-item Resilience Scale (RS-14), the Hospital Anxiety and Depression Scale (HADS), and the World Health Organization Quality of Life-Brief Version (WHOQOL-Bref). Results: A significant linear correlation between resilience and all the areas of quality of life at T0, T1, and T2 emerged. A negative correlation between resilience and anxiety and depressive symptoms emerged, as well as between depression and anxiety and quality of life. Patients with cardiac events during the follow up have shown a worse quality of life and the onset of anxiety-depressive symptoms over time, without changes to the resilience scores. Patients without cardiac events showed an increasing trend in resilience scores. Discussion: Given the speed and simplicity of use of the RS-14 scale, it seems promising to further investigate the real clinical usefulness of this instrument in the cardiology field

    TIMI, GRACE and alternative risk scores in Acute Coronary Syndromes: A meta-analysis of 40 derivation studies on 216,552 patients and of 42 validation studies on 31,625 patients.

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    BACKGROUND: Acute coronary syndromes (ACS) represent a difficult challenge for physicians. Risk scores have become the cornerstone in clinical and interventional decision making. METHODS AND RESULTS: PubMed was systematically searched for ACS risk score studies. They were divided into ACS studies (evaluating Unstable Angina; UA, Non ST Segment Elevation Myocardial Infarction; NSTEMI, and ST Segment Elevation Myocardial Infarction; STEMI), UA/NSTEMI studies or STEMI studies. The c-statistics of validation studies were pooled when appropriate with random-effect methods. 7 derivation studies with 25,525 ACS patients and 15 validation studies including 257,654 people were formally appraised. Pooled analysis of GRACE scores, both at short (0.82; 0.80-0.89 I.C 95%) and long term follow up (0.84; 0.82-0.87; I.C 95%) showed the best performance, with similar results to Simple Risk Index (SRI) derivation cohorts at short term. For NSTEMI/UA, 18 derivation studies with 56,560 patients and 18 validation cohorts with 56,673 patients were included. Pooled analysis of validations studies showed c-statistics of 0.54 (95% CI = 0.52-0.57) and 0.67 (95% CI = 0.62-0.71) for short and long term TIMI validation studies, and 0.83 (95% CI = 0.79-9.87) and 0.80 (95% CI = 0.74-0.89) for short and long term GRACE studies. For STEMI, 15 studies with 134,557 patients with derivation scores, and 17 validation studies with 187,619 patients showed a pooled c-statistic of 0.77 (95% CI = 0.71-0.83) and 0.77 (95% CI = 0.72-0.85) for TIMI at short and long term, and a pooled c-statistic of 0.82 (95% CI = 0.81-0.83) and 0.81 (95% CI = 0.80-0.82) for GRACE at short and long terms respectively. CONCLUSIONS: TIMI and GRACE are the risk scores that up until now have been most extensively investigated, with GRACE performing better. There are other potentially useful ACS risk scores available however these have not undergone rigorous validation. This study suggests that these other scores may be potentially useful and should be further researched

    A Fisher-Rao metric for paracatadioptric images of lines

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    In a central paracatadioptric imaging system a perspective camera takes an image of a scene reflected in a paraboloidal mirror. A 360° field of view is obtained, but the image is severely distorted. In particular, straight lines in the scene project to circles in the image. These distortions make it diffcult to detect projected lines using standard image processing algorithms. The distortions are removed using a Fisher-Rao metric which is defined on the space of projected lines in the paracatadioptric image. The space of projected lines is divided into subsets such that on each subset the Fisher-Rao metric is closely approximated by the Euclidean metric. Each subset is sampled at the vertices of a square grid and values are assigned to the sampled points using an adaptation of the trace transform. The result is a set of digital images to which standard image processing algorithms can be applied. The effectiveness of this approach to line detection is illustrated using two algorithms, both of which are based on the Sobel edge operator. The task of line detection is reduced to the task of finding isolated peaks in a Sobel image. An experimental comparison is made between these two algorithms and third algorithm taken from the literature and based on the Hough transform
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