71 research outputs found

    Scanning X-ray diffraction microscopy of a 6 GHz surface acoustic wave

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    Surface acoustic waves at frequencies beyond a few GHz are promising components for quantum technology applications. Applying scanning X-ray diffraction microcopy we directly map the locally resolved components of the three-dimensional strain field generated by a standing surface acoustic wave on GaAs with wavelength λ≃500 \lambda\simeq500\,nm corresponding to frequencies near 6 GHz. We find that the lattice distortions perpendicular to the surface are phase-shifted compared to those in propagation direction. Model calculations based on Rayleigh waves confirm our measurements. Our results represent a break through in providing a full characterization of a radio frequency surface acoustic wave beyond plain imaging.Comment: 9 pages, 6 figure

    Effect of elevated CO2 on organic matter pools and fluxes in a summer Baltic Sea plankton community

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    Ocean acidification is expected to influence plankton community structure and biogeochemical element cycles. To date, the response of plankton communities to elevated CO2 has been studied primarily during nutrient-stimulated blooms. In this CO2 manipulation study, we used large-volume (similar to 55 m(3)) pelagic in situ mesocosms to enclose a natural summer, post-spring-bloom plankton assemblage in the Baltic Sea to investigate the response of organic matter pools to ocean acidification. The carbonate system in the six mesocosms was manipulated to yield average fCO(2) ranging between 365 and similar to 1230 mu atm with no adjustment of naturally available nutrient concentrations. Plankton community development and key biogeochemical element pools' were subsequently followed in this nitrogen-limited ecosystem over a period of 7 weeks. We observed higher sustained chlorophyll a and particulate matter concentrations (similar to 25% higher) and lower inorganic phosphate concentrations in the water column in the highest fCO(2) treatment (1231 mu atm) during the final 2 weeks of the study period (Phase III), when there was low net change in particulate and dissolved matter pools. Size-fractionated phytoplankton pigment analyses indicated that these differences were driven by picophytoplankton (<2 mu m) and were already established early in the experiment during an initial warm and more productive period with overall elevated chlorophyll a and particulate matter concentrations. However, the influence of picophyto-plankton on bulk organic matter pools was masked by high biomass of larger plankton until Phase III, when the contribution of the small size fraction (<2 mu m) increased to up to 90% of chlorophyll a. In this phase, a CO2-driven increase in water column particulate carbon did not lead to enhanced sinking material flux but was instead reflected in increased dissolved organic carbon concentrations. Hence ocean acidification may induce changes in organic matter partitioning in the upper water column during the low-nitrogen summer period in the Baltic Sea.Peer reviewe

    Familial aggregation of MATRICS Consensus Cognitive Battery scores in a large sample of outpatients with schizophrenia and their unaffected relatives

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    The increased use of the MATRICS Consensus Cognitive Battery (MCCB) to investigate cognitive dysfunctions in schizophrenia fostered interest in its sensitivity in the context of family studies. As various measures of the same cognitive domains may have different power to distinguish between unaffected relatives of patients and controls, the relative sensitivity of MCCB tests for relative-control differences has to be established. We compared MCCB scores of 852 outpatients with schizophrenia (SCZ) with those of 342 unaffected relatives (REL) and a normative Italian sample of 774 healthy subjects (HCS). We examined familial aggregation of cognitive impairment by investigating within-family prediction of MCCB scores based on probands' scores

    Low pre-transplant levels of mannosebinding lectin are associated with viral infections and mortality after haematopoietic allogeneic stem cell transplantation

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    Background: Mannose-binding lectin (MBL) is a key component of innate immunity. Low serum MBL levels, related to promoter polymorphism and structural variants, have been associated with an increased risk of infection. The aim of this work was to analyse the incidence and severity of infections and mortality in relation to the MBL2 genotype and MBL levels in patients underwent allogeneic haematopoietic stem cell transplantation (Allo-HSCT). Results: This was a prospective cohort study of 72 consecutive patients underwent Allo-HSCT between January 2007 and June 2009 in a tertiary referral centre. Three periods were considered in the patients? follow-up: the early period (0?30 days after Allo-HSCT), the intermediate period (30?100 days after Allo-HSCT) and the late period (> 100 days after Allo-HSCT). A commercial line probe assay for MBL2 genotyping and an ELISA Kit were used to measure MBL levels. A total of 220 episodes of infection were collected in the 72 patients. No association between donor or recipient MBL2 genotype and infection was found. The first episode of infection presented earlier in patients with pre-transplant MBL levels of < 1000 ng/ml (median 6d vs 8d, p = 0.036). MBL levels < 1000 ng/ml in the pre-transplant period (risk ratio (RR) 2.48, 95% CI 1.00?6.13), neutropenic period (0?30 days, RR 3.28, 95% CI 1.53?7.06) and intermediate period (30?100 days, RR 2.37, 95% CI 1.15?4.90) were associated with increased risk of virus infection. No association with bacterial or fungal disease was found. Mortality was associated with pre-transplant MBL levels < 1000 ng/ml (hazard ratio 5.55, 95% CI 1.17?26.30, p = 0.03) but not with MBL2 genotype. Conclusions: Patients who underwent Allo-HSCT with low pre-transplant MBL levels presented the first episode of infection earlier and had an increased risk of viral infections and mortality in the first 6 months post-transplant. Thus, pre-transplant MBL levels would be important in predicting susceptibility to viral infections and mortality and might be considered a biomarker to be included in the pre-transplantation risk assessment.This work was supported by grants from the Fondo de Investigaciones Sanitarias (Ministry of Health of Spain) PI04/0492 to MC Fariñas and Instituto de Investigación Sanitaria Valdecilla (IDIVAL) API 06/01. The content of the paper is solely the responsibility of the authors and does not necessarily represent the official views. The funding body was not involved in the design of the study, collection or analysis of the data, interpretation of the data, or in the writing of the manuscript

    Familial aggregation of MATRICS Consensus Cognitive Battery scores in a large sample of outpatients with schizophrenia and their unaffected relatives

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    Background The increased use of the MATRICS Consensus Cognitive Battery (MCCB) to investigate cognitive dysfunctions in schizophrenia fostered interest in its sensitivity in the context of family studies. As various measures of the same cognitive domains may have different power to distinguish between unaffected relatives of patients and controls, the relative sensitivity of MCCB tests for relative-control differences has to be established. We compared MCCB scores of 852 outpatients with schizophrenia (SCZ) with those of 342 unaffected relatives (REL) and a normative Italian sample of 774 healthy subjects (HCS). We examined familial aggregation of cognitive impairment by investigating within-family prediction of MCCB scores based on probands' scores.Methods Multivariate analysis of variance was used to analyze group differences in adjusted MCCB scores. Weighted least-squares analysis was used to investigate whether probands' MCCB scores predicted REL neurocognitive performance.Results SCZ were significantly impaired on all MCCB domains. REL had intermediate scores between SCZ and HCS, showing a similar pattern of impairment, except for social cognition. Proband's scores significantly predicted REL MCCB scores on all domains except for visual learning.Conclusions In a large sample of stable patients with schizophrenia, living in the community, and in their unaffected relatives, MCCB demonstrated sensitivity to cognitive deficits in both groups. Our findings of significant within-family prediction of MCCB scores might reflect disease-related genetic or environmental factors

    Influence of Ocean Acidification on a Natural Winter-to-Summer Plankton Succession : First Insights from a Long-Term Mesocosm Study Draw Attention to Periods of Low Nutrient Concentrations

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    Every year, the oceans absorb about 30% of anthropogenic carbon dioxide (CO2) leading to a re-equilibration of the marine carbonate system and decreasing seawater pH. Today, there is increasing awareness that these changes-summarized by the term ocean acidification (OA)-could differentially affect the competitive ability of marine organisms, thereby provoking a restructuring of marine ecosystems and biogeochemical element cycles. In winter 2013, we deployed ten pelagic mesocosms in the Gullmar Fjord at the Swedish west coast in order to study the effect of OA on plankton ecology and biogeochemistry under close to natural conditions. Five of the ten mesocosms were left unperturbed and served as controls (similar to 380 mu atm pCO(2)), whereas the others were enriched with CO2-saturated water to simulate realistic end-of-the-century carbonate chemistry conditions (mu 760 mu atm pCO(2)). We ran the experiment for 113 days which allowed us to study the influence of high CO2 on an entire winter-to-summer plankton succession and to investigate the potential of some plankton organisms for evolutionary adaptation to OA in their natural environment. This paper is the first in a PLOS collection and provides a detailed overview on the experimental design, important events, and the key complexities of such a "long-term mesocosm" approach. Furthermore, we analyzed whether simulated end-of-the-century carbonate chemistry conditions could lead to a significant restructuring of the plankton community in the course of the succession. At the level of detail analyzed in this overview paper we found that CO2-induced differences in plankton community composition were non-detectable during most of the succession except for a period where a phytoplankton bloom was fueled by remineralized nutrients. These results indicate: (1) Long-term studies with pelagic ecosystems are necessary to uncover OA-sensitive stages of succession. (2) Plankton communities fueled by regenerated nutrients may be more responsive to changing carbonate chemistry than those having access to high inorganic nutrient concentrations and may deserve particular attention in future studies.Peer reviewe

    Uso de hormonas en la especie equina

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    La presente revisión bibliográfica tiende a reunir el conocimiento actual sobre los mecanismos hormonales que rigen la reproducción en la especie equina, como especialmente las indicaciones, efectos, dosificaciones y limitantes del uso de preparados hormonales en yeguas y potros.Las experiencias propias de los autores, que complementan la revisión bibliográfica, incluyen el uso de hormonas liberadoras de gonadotrofinas (GnRH), Gonadotrofinas sérica y coriónica, estrógenos, gestágenos y prosta­glandina en yeguas no gestantes, la interrupción de la gestación e inducción de partos con prostaglandinas, corticoesteroides y oxitocina. Se agregan la aplicación de gonadotrofinas y andrógenos en potros, con fines correctivos (deficiencias, maldescensus testiculorum) y diagnósticos (criptorquídea).Se advierte la inconveniencia de enmascarar posibles deficiencias hereditarias, mediante la aplicación sustitutiva de preparados hormonales, en especial de progesterona y testosterona en yeguas y potros respectivamente

    Uso de hormonas en la especie equina

    No full text
    La presente revisión bibliográfica tiende a reunir el conocimiento actual sobre los mecanismos hormonales que rigen la reproducción en la especie equina, como especialmente las indicaciones, efectos, dosificaciones y limitantes del uso de preparados hormonales en yeguas y potros.Las experiencias propias de los autores, que complementan la revisión bibliográfica, incluyen el uso de hormonas liberadoras de gonadotrofinas (GnRH), Gonadotrofinas sérica y coriónica, estrógenos, gestágenos y prosta­glandina en yeguas no gestantes, la interrupción de la gestación e inducción de partos con prostaglandinas, corticoesteroides y oxitocina. Se agregan la aplicación de gonadotrofinas y andrógenos en potros, con fines correctivos (deficiencias, maldescensus testiculorum) y diagnósticos (criptorquídea).Se advierte la inconveniencia de enmascarar posibles deficiencias hereditarias, mediante la aplicación sustitutiva de preparados hormonales, en especial de progesterona y testosterona en yeguas y potros respectivamente
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