1,366 research outputs found
A commentary on recent water safety initiatives in the context of water utility risk management.
Over the last decade, suppliers of drinking water have recognised the
limitations of relying solely on end-product monitoring to ensure safe water
quality and have sought to reinforce their approach by adopting preventative
strategies where risks are proactively identified, assessed and managed. This is
leading to the development of water safety plans; structured āroute mapsā for
managing risks to water supply, from catchment to consumer taps. This paper
reviews the Hazard Analysis and Critical Control Point (HACCP) procedure on
which many water safety plans are based and considers its appropriateness in the
context of drinking water risk management. We examine water safety plans in a
broad context, looking at a variety of monitoring, optimisation and risk
management initiatives that can be taken to improve drinking water safety. These
are cross-compared using a simple framework that facilitates an integrated
approach to water safety. Finally, we look at how risk management practices are
being integrated across water companies and how this is likely to affect the
future development of water safety p
Restorative Justice, Responsive Regulation and Social Work
Two of the dichotomies or tensions at the heart of this profession are especially important for the themes of this special issue on restorative justice and responsive regulation. These are the relation between formal and informal helping and between care and control, or empowerment and coercion. In this article, we make a case for the importance of Braithwaite\u27s work, especially his (2002) book, Restorative Justice and Responsive Regulation, for conceptualizing the nature of social work in relation to these dualities. Since Braithwaite\u27s writings do not have social work or social welfare scholars and professionals as their primary audience and are less familiar to much of that audience than they should be, we seek here to provide a context for reading both Braithwaite and this issue of the Journal of Sociology and Social Welfare
Lower-rim ferrocenyl substituted calixarenes: new electrochemical sensors for anions
New ferrocene substituted calix[4 and 5]arenes have been prepared and the crystal structure of a lower-rim substituted bis ferrocene calix[4]arene (7) has been elucidated. The respective ferrocene/ferrocenium redox-couples of compounds 6 (a calix[4]arene tetra ferrocene amide) and 8 (a calix[5]arene pentaferrocene amide) are shown to be significantly cathodically perturbed in the presence of anions by up to 160 mV in the presence of dihydrogen phosphate
Pando\u27s Lessons: Restoration of a Giant Aspen Clone
A 106 acre (43 ha) aspen clone lives in the Fishlake National Forest in south-central Utah. Clones are comprised of multiple aspen stems, called ramets, which are genetically identical. This particular colony of ramets was named āPandoā (Latin for āI spreadā) by researchers believing it to be the largest living organism by mass on earth. Recently, forest managers have noted a rapid dying of mature stems without recruitment of younger trees. This unsustainable situation has galvanized restoration efforts at Pando. Human interventions caused this imbalance; restoration will rely on protection, monitoring, and innovation. As a laboratory, this forest icon may provide insights for much broader human-nature interactions
Effects of glial cell line-derived neurotrophic factor on dental pulp cells
This study investigated the effects of glial cell line-derived neurotrophic factor (GDNF) on dental pulp cells (DPCs). Cultures of DPCs expressed GDNF as well as its receptors, GFRĪ±1 and RET. Addition of recombinant GDNF to cultures in serum-containing medium did not significantly affect DPC growth; however, GDNF dose-dependently increased viable cell number under serum-free culture conditions. Live/dead, lactate dehydrogenase (LDH), and caspases-3/-7 assays demonstrated that cell death occurred under serum-free conditions, and that GDNF significantly reduced the number of dead cells by inhibiting apoptotic cell death. GDNF also stimulated cell proliferation in serum-free conditions, as assessed by the BrdU incorporation assay. The effect of GDNF was abolished in the presence of inhibitors to GFRĪ±1 and RET suggesting receptor-mediated events. This study also demonstrated that GDNF counteracted TNFĪ±-induced DPC cytotoxicity, suggesting that GDNF may be cytoprotective under disease conditions. In conclusion, our findings indicate that GDNF promotes cell survival and proliferation of DPCs and suggest that GDNF may play a multifunctional role in the regulation of dental pulp homeostasis
The Impact of Total Sleep Deprivation on Neuropsychological Functioning.
Extended sleep deprivation has been shown to produce impairments in sustained attention and vigilance, especially if the deprivation period is greater than 48 hours. However little is known about the effects of sleep deprivation on performance of cognitive tasks considered to be measures of higher cortical functioning such as cognitive flexibility and the capacity to shift response set. These two activities are associated with intact functioning of the frontal lobes of the cerebral cortex while attention and vigilance tasks are not considered to be part of this type of cognitive activity and are not associated with frontal lobe function. One current hypothesis is that sleep deprivation of a shorter duration (34-36 hours) adversely affects higher cortical function while effects on attention and vigilance are relatively mild. Performance on an intelligence test, a test of sustained attention and tests designed to measure higher cortical function were compared in a group of 29 subjects who underwent 34-36 hours of continuous sleep deprivation and 32 normal sleeping control subjects. No significant group performance differences were noted on any measure. One night of total sleep deprivation does not appear to significantly impair performance on tasks that are designed to assess higher cortical functioning or frontal lobe function
Growth and characterization of gallium arsenide grown by conventional and current-controlled liquid phase epitaxy.
Thesis. 1978. Ph.D.--Massachusetts Institute of Technology. Dept. of Materials Science and Engineering.MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.Vita.Includes bibliographical references.Ph.D
Transcytosis and brain uptake of transferrin-containing nanoparticles by tuning avidity to transferrin receptor
Receptor-mediated transcytosis across the bloodābrain barrier (BBB) may be a useful way to transport therapeutics into the brain. Here we report that transferrin (Tf)-containing gold nanoparticles can reach the brain parenchyma from systemic administration in mice through a receptor-mediated transcytosis pathway. This transport is aided by tuning the nanoparticle avidity to Tf receptor (TfR), which is correlated with nanoparticle size and total amount of Tf decorating the nanoparticle surface. Nanoparticles of both 45 nm and 80 nm diameter reach the brain parenchyma, and their accumulation there (visualized by silver enhancement light microscopy in combination with transmission electron microscopy imaging) is observed to be dependent on Tf content (avidity); nanoparticles with large amounts of Tf remain strongly attached to brain endothelial cells, whereas those with less Tf are capable of both interacting with TfR on the luminal side of the BBB and detaching from TfR on the brain side of the BBB. The requirement of proper avidity for nanoparticles to reach the brain parenchyma is consistent with recent behavior observed with transcytosing antibodies that bind to TfR
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