231 research outputs found
Magnetostratigraphy of Cueva Del Aleman, Isla de Mona, Puerto Rico and the Species Duration of Audobon\u27s Shearwater
Magnetostratigraphic analysis of deposits exposed in Cueva del Aleman shows two reversed and two normal chronozones. The lower normal polarity event is observed in a clastic dike and probably predates initial cave formation. Sediments deposited inside the cave proper show a R-N-R sequence and probably date to at least 1.8 Ma. A fossiliferous clastic dike contains normal polarity with an overlying reversed magnetozone. Audubon’s Shearwater (bird) bones occur in the dike, which is tentatively correlated with the lower N polarity zone predating cave formation. If this correlation is correct, the Audubon’s Shearwater (Puffinus lherminieri) range can be extended back to at least 1.8 Ma, the Olduvai subchron
Novel combination of CRISPR-based gene drives eliminates resistance and localises spread
Invasive species are among the major driving forces behind biodiversity loss. Gene drive technology may offer a humane, efficient and cost-effective method of control. For safe and effective deployment it is vital that a gene drive is both self-limiting and can overcome evolutionary resistance. We present HD-ClvR in this modelling study, a novel combination of CRISPR-based gene drives that eliminates resistance and localises spread. As a case study, we model HD-ClvR in the grey squirrel (Sciurus carolinensis), which is an invasive pest in the UK and responsible for both biodiversity and economic losses. HD-ClvR combats resistance allele formation by combining a homing gene drive with a cleave-and-rescue gene drive. The inclusion of a self-limiting daisyfield gene drive allows for controllable localisation based on animal supplementation. We use both randomly mating and spatial models to simulate this strategy. Our findings show that HD-ClvR could effectively control a targeted grey squirrel population, with little risk to other populations. HD-ClvR offers an efficient, self-limiting and controllable gene drive for managing invasive pests.</p
Knowledge economy and the social economy : university support for community enterprise development as a strategy for economic regeneration in distressed regions in Canada and Mexico
Meeting: Triple Helix Conference, 3 Jan. 1996, Amsterdam, N
Longitudinal changes in juvenile and adolescent body mass indices before, during, and after the COVID-19 lockdown in New Zealand.
This study uses longitudinal data from school children in Dunedin, New Zealand, to evaluate impacts of COVID-19 lockdown measures on changes in body mass (BMI, kg/m ). Impacts are assessed using two non-mutually exclusive hypotheses. The "structured days" hypothesis holds that children tend to alter sleep patterns, reduce activity and increase snacking when not in structured environments. The bidirectional hypothesis proposes that over-weight or obese children are predisposed to further gains in unstructured settings. Juveniles and adolescents (n = 95, 60% female) were recruited from Dunedin schools. Repeated measures analyses assessed variation in intra-individual change in BMI during four periods: P1 (before summer break), P2 (during summer break), P3 (during the COVID-19 lockdown), and P4 (after the lockdown ended). The model also examined if these changes were influenced by participants' sex or body size early in the first period assessed using log-transformed BMI, log-transformed weight, height, or lower leg length. Repeated measures analyses of per month gains in BMI (kg/m ) during the four periods revealed consistent period (p ≤ .001), period by sex (p ≤ .010), and period by body size (p ≤ .001) interactions across all four body size proxies. Both sexes experienced the greatest gains during the lockdown (P3), but differed in response to their summer break (P2). Results are mostly consistent with the "structured days" hypothesis, but challenge the bidirectional hypothesis as defined. Further research better characterizing risks of gains in adiposity are needed. [Abstract copyright: © 2023 The Authors. American Journal of Human Biology published by Wiley Periodicals LLC.
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Trust: A Planning Guide for Wildfire Agencies and Practitioners—An International Collaboration Drawing on Research and Management Experience in Australia, Canada, and the United States
This planning guide is the outcome of an international collaboration of researchers and practitioners/field managers working in communities at risk of wildfire in three countries. Initially, the team of social scientists from Australia, Canada, and the United States utilized the collective research literature to examine factors that influence stakeholder trust. A working draft of this document was shared with experienced agency personnel and community leaders previous to interactive workshops and field visits in each country. This allowed for deliberations of the essential features of building trust among parties. The discussions and contributions, as well as subsequent review, by workshop participants shaped this final document
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