5,224 research outputs found
A marine reservoir effect ĪR value for Kitandach, in Prince Rupert Harbour, British Columbia, Canada
Prince Rupert Harbour (PRH), on the north Pacific Coast of British Columbia, contains at least 157 shell middens, of which 66 are known villages, in an area of approximately 180 km. These sites span the last 9500 yr and in
some cases are immense, exceeding 20,000 m surface area and several meters in depth. Recent archaeological research in PRH has become increasingly reliant on radiocarbon dates from marine shell for developing chronologies. However, this is problematic as the local marine reservoir effect (MRE) remains poorly understood in the region. To account for
the MRE and to better date the Harbourās sites, we propose a ĪR of 273 Ā± 38 for the PRH area, based on our work at the site of Kitandach (GbTo-34), a massive shell midden-village centrally located within the Harbour. We followed the multiple paired sample approach for samples from speci
fic contexts and ensured contemporaneity within the groups of marine and terrestrial materials by statistically assessing for outliers using the Ļ2
test. Taking together, the results for this and previous studies, it appears the MRE was fairly constant over the past 5000 yr
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Where's the harm? A social marketing approach to reframing 'problem' drinking cultures
Alcohol consumption is often linked to a broad range of social and health problems, yet alcohol also plays a fundamental role in social bonding between people. This paper considers the potential of social marketing to contribute to alcohol consumption reduction and reframe social norms that encourage 'problem' drinking. Based on qualitative research with a variety of Scottish drinkers, the paper emphasises how and why a better understanding of the culturally bound meanings of alcohol (e.g. social identity, self-concept) are of crucial importance to inform any social marketing approach to reframing excessive drinking
A Critical Review of Constraint-Induced Movement Therapy and Forced Use in Children With Hemiplegia
Hemiplegia is a physical impairment that can occur in childhood following head trauma, cerebral vascular accident or transient ischemic attack (stroke), brain tumor, or congenital or perinatal injury. One of the most disabling symptoms of hemiplegia is unilaterally impaired hand and arm function. Sensory and motor impairments in children with hemiplegia compromise movement efficiency. Such children often tend not to use the affected extremity, which may further exacerbate the impairments, resulting in a developmentally learned non-use of the involved upper extremity, termed ādevelopmental disuseā. Recent studies suggest that children with hemiplegia benefit from intensive practice. Forced use and Constraint-lnduced Movement Therapy (CI therapy) are recent therapeutic interventions involving the restraint of the non-involved upper extremity and intensive practice with the involved upper extremity. These approaches were designed for adults with hemiplegia, and increasing evidence suggests that they are efficacious in this population. Recently, forced use and constraint-induced therapy have been applied to children with hemiplegia. In this review, we provide a brief description of forced use and CI therapy and their historical basis, provide a summary of studies of these interventions in children, and discuss a number of important theoretical considerations, as well as implications for postural control. We will show that whereas the studies to date suggest that both forced use and CI therapy appear to be promising for improving hand function in children with hemiplegia, the data are limited. Substantially more work must be performed before this approach can be advocated for general clinical use
Allosteric p97 inhibitors can overcome resistance to ATP-competitive p97 inhibitors for potential anti-cancer therapy
A major challenge of targeted cancer therapy is the selection for drugāresistant mutations in tumor cells leading to loss of treatment effectiveness. p97/VCP is a central regulator of protein homeostasis and a promising antiācancer target because of its vital role in cell growth and survival. One ATPācompetitive p97 inhibitor, CBā5083, has entered clinical trials. Selective pressure on HCT116 cells treated with CBā5083 identified 5 different resistant mutants. Identification of p97 inhibitors with different mechanisms of action would offer the potential to overcome this class of resistance mutations. Our results demonstrate that two CBā5083 resistant p97 mutants, N660K and T688A, were also resistant to several other ATPācompetitive p97 inhibitors, whereas inhibition by two allosteric p97 inhibitors NMSā873 and UPCDCā30245 were unaffected by these mutations. We also established a CBā5083 resistant cell line that harbors a new p97 double mutation (D649A/T688A). While CBā5083, NMSā873, and UPCDCā30245 all effectively inhibited proliferation of the parental HCT116 cell line, NMSā873 and UPCDCā30245 were 30āfold more potent than CBā5083 in inhibiting the CBā5083 resistant D649A/T688A double mutant. Our results suggest that allosteric p97 inhibitors are promising alternatives when resistance to ATPācompetitive p97 inhibitors arises during antiācancer treatment
Biofilm-forming capability of highly virulent, multidrug-resistant Candida auris
The emerging multidrug-resistant yeast pathogen Candida auris has attracted considerable attention as a source of healthcareāassociated infections. We report that this highly virulent yeast has the capacity to form antifungal resistant biofilms sensitive to the disinfectant chlorhexidine in vitro
Estimating marine reservoir effects in archaeological chronologies: Comparing ĪR calculations in Prince Rupert Harbour, British Columbia, Canada
The best method for quantifying the marine reservoir effect (MRE) using the global IntCal Marine13 calibration curve remains
unresolved. Archaeologists frequently quantify uncertainty on MRE values as errors computed from single pairs of marineterrestrial
radiocarbon ages, which we argue significantly overstates their accuracy and precision. Here, we review the
assumptions, methods, and applications of estimating MRE via an estimate of the additional regional offset between the marine
and terrestrial calibration curves (ĪR) for the Prince Rupert Harbour (PRH) region of British Columbia, Canada.We acknowledge
the influence on ĪR of MRE variation as (1) a dynamic oceanographic process, (2) its variable expression in biochemical
and geochemical pathways, and (3) compounding errors in sample selection, measurement, and calculation. We examine
a large set of marine-terrestrial pairs (n = 63) from PRH to compare a common archaeological practice of estimating uncertainty
from means that generate an uncertainty value of Ā±49 years with a revised, more appropriate estimate of error of Ā± 230
years. However, we argue that the use of multiple-pair samples estimates the PRH ĪR as 273 Ā± 38 years for the last 5,000 years.
Calculations of error that do not consider these issues may generate more inaccurate age estimates with unjustifiable precision
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