147 research outputs found

    Long-term and trans-life-cycle effects of exposure to ocean acidification in the green sea urchin Strongylocentrotus droebachiensis

    Get PDF
    Anthropogenic CO2 emissions are acidifying the world’s oceans. A growing body of evidence demonstrates that ocean acidification can impact survival, growth, development and physiology of marine invertebrates. Here, we tested the impact of long-term (up to 16 months) and trans-life-cycle (adult, embryo/larvae and juvenile) exposure to elevated pCO2 (1,200 μatm, compared to control 400 μatm) on the green sea urchin Strongylocentrotus droebachiensis. Female fecundity was decreased 4.5-fold when acclimated to elevated pCO2 for 4 months during reproductive conditioning, while no difference was observed in females acclimated for 16 months. Moreover, adult pre-exposure for 4 months to elevated pCO2 had a direct negative impact on subsequent larval settlement success. Five to nine times fewer offspring reached the juvenile stage in cultures using gametes collected from adults previously acclimated to high pCO2 for 4 months. However, no difference in larval survival was observed when adults were pre-exposed for 16 months to elevated pCO2. pCO2 had no direct negative impact on juvenile survival except when both larvae and juveniles were raised in elevated pCO2. These negative effects on settlement success and juvenile survival can be attributed to carry-over effects from adults to larvae and from larvae to juveniles. Our results support the contention that adult sea urchins can acclimate to moderately elevated pCO2 in a matter of a few months and that carry-over effects can exacerbate the negative impact of ocean acidification on larvae and juveniles

    Spared unconscious influences of spatial memory in diencephalic amnesia

    Get PDF
    Spatial memory is crucial to our daily lives and in part strongly depends on automatic, implicit memory processes. This study investigates the neurocognitive basis of conscious and unconscious influences of object–location memory in amnesic patients with Korsakoff’s syndrome (N = 23) and healthy controls (N = 18) using a process-dissociation procedure in a computerized spatial memory task. As expected, the patients performed substantially worse on the conscious memory measures but showed even slightly stronger effects of unconscious influences than the controls. Moreover, a delayed test administered after 1 week revealed a strong decline in conscious influences in the patients, while unconscious influences were not affected. The presented results suggest that conscious and unconscious influences of spatial memory can be clearly dissociated in Korsakoff’s syndrome

    Electrode modification using nanocomposites of electropolymerised cobalt phthalocyanines supported on multiwalled carbon nanotubes

    Get PDF
    A polymer of tetra(4)-(4,6-diaminopyrimidin-2-ylthio) phthalocyaninatocobalt(II) (CoPyPc) has been deposited over a multiwalled carbon nanotube (MWCNT) platform and its electrocatalytic properties investigated side by side with polymerized cobalt tetraamino phthalocyanine (CoTAPc). X-ray photoelectron spectroscopy, scanning electron microscopy and cyclic voltammetry studies were used for characterization of the prepared polymers of cobalt phthalocyanine derivatives and their nanocomposites. L-Cysteine was used as a test analyte for the electrocatalytic activity of the nanocomposites of polymerized cobalt phthalocyanines and multiwalled carbon nanotubes. The electrocatalytic activity of both polymerized cobalt phthalocyanines was found to be superior when polymerization was done on top of MWCNTs compared to bare glassy carbon electrode. A higher sensitivity for L-cysteine detection was obtained on CoTAPc compared to CoPyPc

    The Salivary Secretome of the Tsetse Fly Glossina pallidipes (Diptera: Glossinidae) Infected by Salivary Gland Hypertrophy Virus

    Get PDF
    Tsetse fly (Diptera; Glossinidae) transmits two devastating diseases to farmers (human African Trypanosomiasis; HAT) and their livestock (Animal African Trypanosomiasis; AAT) in 37 sub-Saharan African countries. During the rainy seasons, vast areas of fertile, arable land remain uncultivated as farmers flee their homes due to the presence of tsetse. Available drugs against trypanosomiasis are ineffective and difficult to administer. Control of the tsetse vector by Sterile Insect Technique (SIT) has been effective. This method involves repeated release of sterilized males into wild tsetse populations, which compete with wild type males for females. Upon mating, there is no offspring, leading to reduction in tsetse populations and thus relief from trypanosomiasis. The SIT method requires large-scale tsetse rearing to produce sterile males. However, tsetse colony productivity is hampered by infections with the salivary gland hypertrophy virus, which is transmitted via saliva as flies take blood meals during membrane feeding and often leads to colony collapse. Here, we investigated the salivary gland secretome proteins of virus-infected tsetse to broaden our understanding of virus infection, transmission and pathology. By this approach, we obtain insight in tsetse-hytrosavirus interactions and identified potential candidate proteins as targets for developing biotechnological strategies to control viral infections in tsetse colonies

    Repurposing NGO data for better research outcomes: A scoping review of the use and secondary analysis of NGO data in health policy and systems research

    Get PDF
    Background Non-government organisations (NGOs) collect and generate vast amounts of potentially rich data, most of which are not used for research purposes. Secondary analysis of NGO data (their use and analysis in a study for which they were not originally collected) presents an important but largely unrealised opportunity to provide new research insights in critical areas including the evaluation of health policy and programmes. Methods A scoping review of the published literature was performed to identify the extent to which secondary analysis of NGO data has been used in health policy and systems research (HPSR). A tiered analytic approach provided a comprehensive overview and descriptive analyses of the studies which: 1) used data produced or collected by or about NGOs; 2) performed secondary analysis of the NGO data (beyond use of an NGO report as a supporting reference); 3) used NGO-collected clinical data. Results Of the 156 studies which performed secondary analysis of NGO-produced or collected data, 64% (n=100) used NGO-produced reports (e.g. to critique NGO activities and as a contextual reference) and 8% (n=13) analysed NGO-collected clinical data.. Of the studies, 55% investigated service delivery research topics, with 48% undertaken in developing countries and 17% in both developing and developed. NGO-collected clinical data enabled HPSR within marginalised groups (e.g. migrants, people in conflict-affected areas), with some limitations such as inconsistencies and missing data. Conclusion We found evidence that NGO-collected and produced data are most commonly perceived as a source of supporting evidence for HPSR and not as primary source data. However, these data can facilitate research in under-researched marginalised groups and in contexts that are hard to reach by academics, such as conflict-affected areas. NGO–academic collaboration could help address issues of NGO data quality to facilitate their more widespread use in research. Their use could enable relevant and timely research in the areas of health policy, programme evaluation and advocacy to improve health and reduce health inequalities, especially in marginalised groups and developing countries

    Mild cognitive impairment (MCI) and dementia in a sample of adults in the city of Bogotá

    Full text link
    The low prevalence of dementia described in communities is likely due to the low sensitivity of screening tests and an absence of evaluation by specialists. Objective: To estimate the prevalence of mild cognitive impairment (MCI) and dementia in adults older than 50 years. Methods: A two-phase, cross-sectional study was conducted by specialists to evaluate cognition and associated demographic risk factors in 1,235 independent community-dwelling adults from Bogotá. In Phase I, screening was performed using the MMSE and MoCA tests. In Phase II, after application of a comprehensive neuropsychological battery with neurologic and psychiatric evaluations, a cognitive diagnosis was established by consensus. Results: The prevalence found for MCI was 34% and for dementia was 23%. MCI was associated with incomplete high school, OR=1.74 (95%CI=1.23-2.45), and with an age of 70-79 years, OR=1.93 (95%CI=1.47-2.53). A total of 73% of MCI cases were amnestic. Dementia was associated with incomplete primary education, OR=8.98 (95%CI=5.56-14.54), complete primary education, OR=6.23 (95%CI=3.70-10.47), and age older than eighty years, OR=3.49 (95%CI=2.23-5.44). Conclusion: The prevalence of dementia found was greater than the rates reported in previous studies. Low educational level was the main risk factor for cognitive impairment and should be considered in strategic planning for the local health system

    Observation and branching fraction measurement of the decay Ξb- → Λ0 bπ -

    Get PDF

    Modified carbon-containing electrodes in stripping voltammetry of metals

    Full text link

    Impact of menopause and diabetes on atherogenic lipid profile: is it worth to analyse lipoprotein subfractions to assess cardiovascular risk in women?

    Full text link
    corecore