826,962 research outputs found

    Making a Difference in Schools: The Big Brothers Big Sisters School-Based Mentoring Impact Study

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    School-based mentoring is one of the fastest growing forms of mentoring in the US today; yet, few studies have rigorously examined its impacts. This landmark random assignment impact study of Big Brothers Big Sisters School-Based Mentoring is the first national study of this program model. It involves 10 agencies, 71 schools and 1,139 9- to 16-year-old youth randomly assigned to either a treatment group of program participants or a control group of their non-mentored peers. Surveys were administered to all participating youth, their teachers and mentors in the fall of 2004, spring of 2005 and late fall of 2005.The report describes the programs and their participants and answers several key questions, including: Does school-based mentoring work? What kinds of mentoring experiences help to ensure benefits? How much do these programs cost? Our findings highlight both the strengths of this program model and its current limitations and suggest several recommendations for refining this promising model-recommendations that Big Brothers Big Sisters agencies across the country are already working to implement

    Correction:Carbonyl trapping and antiglycative activities of olive oil mill wastewater

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    Correction for ‘Carbonyl trapping and antiglycative activities of olive oil mill wastewater’ by Marta Navarro et al., Food Funct., 2015, 6, 574–583

    The helium-rich cataclysmic variable SBSS 1108+574

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    We present time-resolved spectroscopy and photometry of the dwarf nova SBSS 1108+574, obtained during the 2012 outburst. Its quiescent spectrum is unusually rich in helium, showing broad, double-peaked emission lines from the accretion disc. We measure a line flux ratio He I 5875/Hα = 0.81 ± 0.04, a much higher ratio than typically observed in cataclysmic variable stars (CVs). The outburst spectrum shows hydrogen and helium in absorption, with weak emission of Hα and He I 6678, as well as strong He II emission. From our photometry, we find the superhump period to be 56.34 ± 0.18 min, in agreement with the previously published result. The spectroscopic period, derived from the radial velocities of the emission lines, is found to be 55.3 ± 0.8 min, consistent with a previously identified photometric orbital period, and significantly below the normal CV period minimum. This indicates that the donor in SBSS 1108+574 is highly evolved. The superhump excess derived from our photometry implies a mass ratio of q = 0.086 ± 0.014. Our spectroscopy reveals a grazing eclipse of the large outbursting disc. As the disc is significantly larger during outburst, it is unlikely that an eclipse will be detectable in quiescence. The relatively high accretion rate implied by the detection of outbursts, together with the large mass ratio, suggests that SBSS 1108+574 is still evolving towards its period minimum

    Evaluation of a hydrographic technique to measure on-farm water storage volumes

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    Digital terrain models of on-farm water storages are required to assist in accurately measuring the on-farm water balance and water use efficiency components including storage capacity, inflow, seepage, evaporation and discharge volumes. A hydrographic surveying system combining a high-precision global positioning system (GPS) and a low-cost depth sounder was developed to facilitate the creation of a digital terrain model. The system was validated by comparing the hydrographic terrain model and volume measurements against both a traditional real time kinematic (RTK) land based survey and independent lead line depth measurements. Flat bottomed storage volumes were measured with errors of less than 1 percent using the hydrographic survey technique. A major proportion of the error in small storages was found to be associated with the ability to accurately identify the inflection point between the banks and floor of the storage. However, for larger storages, errors were primarily related to density of sampling points within the storage floor area. Recommendations are provided regarding the appropriate measurement procedures, including sampling point density, for a range of storage sizes

    A freshwater diet-derived C-14 reservoir effect at the Stone Age sites in the Iron Gates gorge

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    Human bones from single inhumation burials and artifacts made from terrestrial mammal (ungulate) bone found in direct association with the skeletons were obtained from the Stone Age site of Schela Cladovei situated just below the iron Gates Gorge of the River Danube. The results of stable isotope analyses of the human bone collagen are consistent with a heavy dependence on aquatic protein while radiocarbon dating of the samples reveals an offset of 300-500 years between the two sample types, indicating a freshwater reservoir effect in the human bone samples, Since protein consumption is by far the major source of nitrogen in the human diet we have assumed a linear relationship between delta(15)N and the level of aquatic protein in each individual's diet and derived a calibration for C-14 age offset versus delta(15)N which has been applied to a series of results from the site at Lepenski Vir within the gorge, The corrected C-14 ages (7310-6720 BP) are now consistent with the previous C-14 age measurements made on charcoal from related contexts (7360-6560 BP). In addition, the data indicate a change from a primarily aquatic to a mixed terrestrial/aquatic diet around 7100 BP and this may be argued as supporting a shift from Mesolithic to Neolithic. This study also has wider implications for the accurate dating of human bone samples when the possibility exists of an aquatic component in the dietary protein and strongly implies that delta(15)N analysis should be undertaken routinely when dating human bones

    Libraries and Learning Innovation and the use of Twitter

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    Libraries and Learning Innovation (LLI) at Leeds Metropolitan University launched its Twitter account (@leedsmetlibrary) just over two years ago; as both Twitter and the technology used to access it are rapidly changing we decided that a review of how we use the site would be timely. This article describes our experiences to date, some of the things we have learnt along the way and plans for the future

    A review of grouper (Epinephelus suillus) fry production research in Malaysia

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    Research on grouper (Epinephelus suillus) fry production in captivity has been carried out in Malaysia since 1986 at Tanjung Demong Marine Finfish Production and Research Centre (TDMFPRC) but the breakthrough was only achieved four years later in 1990. Eggs were obtained through natural and induced spawning in tanks. Natural spawning of grouper in captivity seldom occurred and was unpredictable. However induced spawnings were successfully carried out by injecting human chorionic gonadotropin (hCG) intramuscularly at a dose of 500-1000 IU/kg fish. The results from several trials on larval rearing conducted since 1989 until recently showed that larvae obtained from natural spawnings survived longer with some reaching the juvenile stage. The highest recorded survival rate of 43 days posthatch (32.5 mm total length) was 12.1% at 28-32 °C water temperature. On the other hand, 100% mortality usually occurred in larvae obtained from induced spawning 7 days after hatching. The major constraints of grouper fry production in Malaysia are lack of male spawners, inconsistent and unpredictable natural spawning, small quantity of eggs released every spawning day, poor fertilization and hatching rate, weak hatchlings, and high mortality rate at the early stages of larval development. The latter is probably due mainly to problems on initial feeding

    Seismic modelling and paleoceanography at DSDP Site 574

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    The analysis of high-resolution watergun seismic profiles collected in support of DSDP Leg 85 drilling reveals sev eral major, regionally traceable reflectors that can be correlated over more than 360,000 km2 in the central equatorial Pacific. Synthetic seismograms generated from shipboard physical property measurements (carefully corrected to in situ values) for DSDP Site 574 show excellent agreement with the field records; the agreement suggests that the traveltime to-depth conversion is accurate and permits the precise (± 5 m) location of reflectors in the cored section. The reflectors can be dated (±0.5 Ma) as follows: Orange, 21.5 to 22.5 Ma; Yellow, 20.5 to 21.5 Ma; Lavender, 16 to 17 Ma; Red, 13.5 to 14.5 Ma; Purple, 11 to 12 Ma; Brown, 7 to 8 Ma; and Green, 3 to 4 Ma. Similar analyses at the other Leg 85 sites result in identical ages. The reflectors are thus time surfaces; this chapter relates them to major paleoceanographic events and changes in the relative sea-level curve. The Orange and Yellow reflectors are associated with a marked increase in δ 1 3C, a major change in planktonic foraminiferal assemblages, the development of the deep Circum-Antarctic Current, and the establishment of steep thermal gradients between tropical and polar regions. This reorganization of the oceanic circulation system was probably a response to the opening of the Drake Passage, and it resulted in changes in the chemistry of tropical Pacific waters that caused the induration (and thus impedance contrasts) associated with these reflectors. The Lavender reflector is associated with a large carbonate minimum, the Chron 16 carbon shift, a widespread hiatus (NH2), major eustatic sea-level fluctuations, and a significant increase in silica deposition in the Pacific. It is not associated with 18O enrichment or climatic cooling. We conclude that this event represents an intensification in Antarc tic Bottom Water (AABW) circulation and the partitioning of silica between the Atlantic and the Pacific, caused by the introduction of North Atlantic Deep Water (NADW) in response to paleobathymetric and tectonic events. The Red re flector is associated with a subdued carbonate minimum, a widespread hiatus (NH3), a sea-level drop, significant changes in microfossil assemblages, and a major increase in δ 1 8 that has been linked with the buildup of Antarctic ice. Detailed isotopic analyses reveal that this isotopic shift occurred within an interval of 30,000 yr. and precisely at the depth of the Red reflector. The Purple reflector is associated with an extremely large carbonate minimum, a change in the style of carbonate deposition in the Pacific, a major lithologic boundary, a widespread hiatus (NH4), an increase in the provincialism be tween low and high latitudes in all planktonic microfossil assemblages, an apparent fall in eustatic sea level, an enrich ment in δ 1 8 , and a major North Atlantic reflector interpreted as representing an intensification of North Atlantic bot tom-water circulation. The Brown reflector is roughly associated with a small carbonate minimum, an enrichment in δ 1 8 , the late Miocene 1 3C depletion, a drop in the relative sea-level curve, and major faunal changes. The Green reflector is associated with a large carbonate minimum, an enrichment in δ 1 8 , a major western North Atlantic erosional event, and a widespread eastern Atlantic seismic reflector. The bulk of evidence supports correlation with the onset of Northern Hemisphere glaciation, but detailed isotopic analyses indicate that this isotopic event may be linked to the establishment of colder bottom waters without major ice-sheet development. Several types of reflectors have been identified. The reflectors in the older section result from diagenetic effects; the regionally correctable reflectors are associated with global events. In the younger (post-18 Ma) section, local reflectors are characterized by velocity contrasts, whereas regional reflectors are associated with density contrasts caused by car bonate minima. Two modes of generation of carbonate minima (and thus of reflectors) spanning the equatorial Pacific are (1) the intensification of AABW without the concurrent intensification of NADW and so without fractionation of silica between the Atlantic and the Pacific; this mode results in the less extreme carbonate minima; and (2) the intensifi cation of AABW in response to the intensification of NADW; this mode results in extreme carbonate minima and a cor relation of equatorial Pacific reflectors with North Atlantic events

    MiR-574-5p alleviates sepsis-induced acute lung injury by regulating TRAF6/NF-κB pathway

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    Purpose: To investigate the protective effect of miR-574-5p pretreatment against acute lung injury (ALI) induced by sepsis.Methods: A male C57BL/6 mouse model of sepsis-induced ALI was established by cecal ligation and puncture (CLP) and treated with miR-574-5p agomir (intravenous injection, 80 mg/kg per day, 3 days). After that, blood and lung samples were obtained for histopathological observation. Myeloperoxidase (MPO) activity, inflammatory cell infiltration, and cytokine expression were analyzed. The target gene of miR-574-5p was predicted using TargetScan prediction, and verified by luciferase assay and western blot.Results: In sepsis-induced ALI mice model, downregulation of miR-574-5p was observed. Pretreatment of miR-574-5p significantly alleviated ALI by suppressing histological damage, and reducing MPO activity and inflammatory cell infiltration, as well as decreasing cytokine expression. The  underlying mechanism was that miR-574-5p targeted TNF receptor associated factor 6 (TRAF6) and suppressed the downstream NF-κB pathway. Moreover, TRAF6 overexpression reversed the effects of miR-574-5p on ALI.Conclusion: MiR-574-5p pretreatment suppresses inflammatory responses, thus reducing lung injury induced by sepsis in mice, partly via the regulation of TRAF6 and NF-κB pathway. Therefore, this approach can potentially be used for the clinical management of ALI in humans Keywords: Sepsis, Acute lung injury, MiR-574-5p, TRAF6, NF-κB pathwa
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