2,450 research outputs found

    A 200 Year Record of Carbon-13 and Carbon-14 Variations in a Bermuda Coral

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    A 200 year old brain coral, captured in Bermuda in 1976 was slabbed and x-rayed. Using the annual growth bands sequential, dated samples were taken over the entire growth period of the coral and analyzed for Δ14C, δ13C and δ18O. During the past 80 years atmospheric variations in Δ14C and δ13C due to human effects, such as release of bomb C-14 and dilution of both C-14 and C-13 by fossil fuel burning, are closely tracked by the coral. Prior to 1900 divergences between the coral and tree Δ14C and δ13C can be related to world-wide changes in plant production and possibly oceanic upwelling rates

    Tracing Uganda’s global primary organic pineapple value chain

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    The organic sector is one of the fastest growing sectors globally. The sector provides an opportunity for developing countries to export high value products in the global market. One such opportunity for Uganda is the export of organic pineapples. The organic pineapple enterprise is relatively new, having existed for approximately 10 years. This paper traces the organic pineapple value chain, characterises and explains the functions of the actors in the chain. The study used the Global Value Chain Analysis Framework, using data obtained from 140 organic farmers, 10 exporters and 3 support institutions in Uganda. It is clear from the study that the chain is private- sector-driven, has relatively young smallholder farmers, and comprises of 10 small scale export companies. Only 45% of the organic pineapples produced by farmers reach the organic consumers. Reasons for this included limited processing capacity of exporters, competition from conventional buyers and the few local organic consumers. Other reasons were declining soil fertility, limited regulative institutional support and poor infrastructure. We recommend increased use of soil amendments, favourable legislations and investment environment, increased horizontal coordination among exporters and increasing the range of the organic export products in order to increase organic pineapple sales.Keywords: Certification, organic consumer value strea

    Blackallia, Serichonus and Papistylus: three closely related genera of Rhamnaceae (Pomaderreae) from south-western Australia

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    Recent molecular and morphological studies of Pomaderreae indicate that a number of species that have traditionally been of uncertain affi nity require new genera. Blackallia C.A. Gardner is lectotypified and restricted to one species, B. nudiflora (F. Muell.) Rye & Kellermann, for which a new combination is made. Two new genera are described, Serichonus K.R. Thiele comprising the single species S. gracilipes (Diels) K.R. Thiele, and Papistylus Kellermann, Rye & K.R. Thiele with two species, P. grandiflorus (C.A. Gardner) Kellermann, Rye & K.R. Thiele and the new species P. intropubens Rye. All three genera are restricted to the South West Botanical Province of Western Australia. They are closely related but can be readily distinguished from one another by some significant morphological differences, especially in their inflorescences. A revised key to the genera of Pomaderreae is presented and lectotypes are chosen for B. nudiflora and S. gracilipes.Jürgen Kellermann, Barbara L. Rye & Kevin R. Thiel

    The extrinsic proteins of Photosystem II

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    In this review we examine the structure and function of the extrinsic proteins of Photosystem II. These proteins include PsbO, present in all oxygenic organisms, the PsbP and PsbQ proteins, which are found in higher plants and eukaryotic algae, and the PsbU, PsbV, CyanoQ, and CyanoP proteins, which are found in the cyanobacteria. These proteins serve to optimize oxygen evolution at physiological calcium and chloride concentrations. They also shield the Mn 4CaO 5 cluster from exogenous reductants. Numerous biochemical, genetic and structural studies have been used to probe the structure and function of these proteins within the photosystem. We will discuss the most recent proposed functional roles for these components, their structures (as deduced from biochemical and X-ray crystallographic studies) and the locations of their proposed binding domains within the Photosystem II complex. This article is part of a Special Issue entitled: Photosystem II. © 2011 Elsevier B.V. All rights reserved

    The Impact of Acceptance and Commitment Training and Multicultural Training on the stigmatizing attitudes and professional burnout of substance abuse counselors

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    Empirically validated methods for reducing stigma and prejudice toward recipients of behavioral healthcare services are badly needed. In the present study, two packages presented in one day workshops were compared to a biologically oriented Educational Control condition in the alleviation of stigmatizing attitudes in drug abuse counselors. One, Acceptance and Commitment Training (ACT), utilized acceptance, defusion, mindfulness, and values methods. The other, Multicultural Training, sensitized participants to group prejudices and biases. Measures of stigma and burnout were taken pre-training, post-training, and after a three month follow-up. Results showed that Multicultural Training had an impact on stigmatizing attitudes and burnout post-intervention but not at follow-up, but showed better gains in a sense of personal accomplishment as compared to the Educational Control at follow-up. ACT had a positive impact on stigma at follow-up and on burnout at post-treatment and follow-up and follow-up gains in burnout exceeded those of Multicultural Training. ACT also significantly changed the believability of stigmatizing attitudes. This process mediated the impact of ACT but not Multicultural Training on follow-up stigma and burnout. This preliminary study opens new avenues for reducing stigma and burnout in behavioral health counselors

    Endothelial Nitric Oxide Synthase is Regulated by ERK Phosphorylation at Ser602

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    eNOS (endothelial nitric oxide synthase) contains a MAPK (mitogen-activated protein kinase)-binding site associated with a major eNOS control element. Purified ERK (extracellular-signal-regulated kinase) phosphorylates eNOS with a stoichiometry of 2–3 phosphates per eNOS monomer. Phosphorylation decreases NO synthesis and cytochrome c reductase activity. Three sites of phosphorylation were detected by MS. All sites matched the SP and TP MAPK (mitogen-activated protein kinase) phosphorylation motif. Ser602 lies at the N-terminal edge of the 42-residue eNOS AI (autoinhibitory) element. The pentabasic MAPK-binding site lies at the opposite end of the AI, and other critical regulatory features are between them. Thr46 and Ser58 are located in a flexible region associated with the N terminus of the oxygenase domain. In contrast with PKC (protein kinase C), phosphorylation by ERK did not significantly interfere with CaM (calmodulin) binding as analysed by optical biosensing. Instead, ERK phosphorylation favours a state in which FMN and FAD are in close association and prevents conformational changes that expose reduced FMN to acceptors. The close associations between control sites in a few regions of the molecule suggest that control of signal generation is modulated by multiple inputs interacting directly on the surface of eNOS via overlapping binding domains and tightly grouped targets

    Effect of long-term dietary sphingomyelin supplementation on atherosclerosis in mice

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    Sphingomyelin (SM) levels in the circulation correlate positively with atherosclerosis burden. SM is a ubiquitous component of human diets, but it is unclear if dietary SM increases circulating SM levels. Dietary choline increases atherosclerosis by raising circulating trimethylamine N-oxide (TMAO) levels in mice and humans. As SM has a choline head group, we ask in this study if dietary SM accelerates atherosclerotic lesion development by increasing circulating SM and TMAO levels. Three studies were performed: (Study 1) C57BL/6 mice were maintained on a high fat diet with or without SM supplementation for 4 weeks prior to quantification of serum TMAO and SM levels; (Study 2) atherosclerosis was studied in apoE-/- mice after 16 weeks of a high fat diet without or with SM supplementation and (Study 3) apoE-/- mice were maintained on a chow diet for 19 weeks without or with SM supplementation and antibiotic treatment prior to quantification of atherosclerotic lesions and serum TMAO and SM levels. SM consumption did not increase circulating SM levels or atherosclerosis in high fat-fed apoE-/- mice. Serum TMAO levels in C57BL/6 mice were low and had no effect atherosclerosis lesion development. Dietary SM supplementation significantly reduced atherosclerotic lesion area in the aortic arch of chow-fed apoE-/- mice. This study establishes that dietary SM does not affect circulating SM levels or increase atherosclerosis in high fat-fed apoE-/- mice, but it is anti-atherogenic in chow-fed apoE-/- mice.Rosanna W.S. Chung, Zeneng Wang, Christina A. Bursill, Ben J. Wu, Philip J. Barter, Kerry-Anne Ry

    Designing medical technology for developing countries

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    Resource-poor countries have markedly different healthcare systems. Many developed nations donate medical supplies to these countries, but this often does not meet the needs of the recipients. Our goal is to develop simple healthcare solutions that can be produced in-country so the developing area does not depend on outside sources for its supplies. Our group works on many projects, including sustainable woven grass neck braces and a variety of low-cost sensors. Our designs do not require frequent donations, minimize the use of consumables, and provide better detection and/or treatment of prevalent medical concerns. Our baby monitor will detect skin temperature and control a heating element based on the needs of the infant. Our low-cost glucometer operates with the use of test strips that can be printed for a penny with a standard inkjet printer. This will allow the hospital or clinic to print the strips themselves rather than depend on donated strips. Our bacterial sensor will measure resistance to quickly detect the quantity of bacteria in a sample. We seek sustainable solutions for in-house manufacturing to advance more self-sufficient healthcare systems

    Variability of the winter wind waves and swell in the North Atlantic and North Pacific as revealed by the Voluntary Observing Ship data

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    This paper analyses secular changes and interannual variability in the wind wave, swell, and significant wave height (SWH) characteristics over the North Atlantic and North Pacific on the basis of wind wave climatology derived from the visual wave observations of voluntary observing ship (VOS) officers. These data are available from the International Comprehensive Ocean–Atmosphere Data Set (ICOADS) collection of surface meteorological observations for 1958–2002, but require much more complicated preprocessing than standard meteorological variables such as sea level pressure, temperature, and wind. Visual VOS data allow for separate analysis of changes in wind sea and swell, as well as in significant wave height, which has been derived from wind sea and swell estimates. In both North Atlantic and North Pacific midlatitudes winter significant wave height shows a secular increase from 10 to 40 cm decade−1 during the last 45 yr. However, in the North Atlantic the patterns of trend changes for wind sea and swell are quite different from each other, showing opposite signs of changes in the northeast Atlantic. Trend patterns of wind sea, swell, and SWH in the North Pacific are more consistent with each other. Qualitatively the same conclusions hold for the analysis of interannual variability whose leading modes demonstrate noticeable differences for wind sea and swell. Statistical analysis shows that variability in wind sea is closely associated with the local wind speed, while swell changes can be driven by the variations in the cyclone counts, implying the importance of forcing frequency for the resulting changes in significant wave height. This mechanism of differences in variability patterns of wind sea and swell is likely more realistic than the northeastward propagation of swells from the regions from which the wind sea signal originates
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