21 research outputs found

    Plain Language Summary: An investigation into different sampling techniques and geographic variation in size-fecundity parameters of the American lobster, H. americanus

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    This thesis focuses on two main aspects, the first of which looks at non-­‐invasive sampling techniques to estimate egg number on female lobsters and the second looks at a model that can predict the relationship between female size and egg number from latitude. The non-­‐invasive sampling techniques estimate egg number for the female American lobster (Homarus americanus) based on measurements and digital image analysis. Non-­‐invasive estimates of egg number can now be made that require the removal of only ten eggs per female instead of the entire egg mass. Applications of this technique include the evaluation of the effectiveness of conservation measures, such as v-­‐notching or the establishment of closed areas, aimed at increasing egg production, where differences in egg production can be measured without the use of destructive sampling techniques. In order to create a model able to predict the number of eggs on a female based on her carapace length throughout the species’ range, fecundity estimates for American lobster (H. americanus) from 11 different locations in the Northwest Atlantic (from the Strait of Belle Isle, Newfoundland to Buzzards Bay, Massachusetts) were obtained. The data were then analyzed for geographic variation and a distinct change with latitude was found in the model parameter b. This was then used to create a model that can predict size-­‐egg number relationships from latitude. This model will allow for future egg number estimates to be made, utilizing size data from latitude for any population in the Northwest Atlantic

    Plain Language Summary: Latitudinal variation in growth rates of American lobster (Homarus americanus) at the scale of the commercial range

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    This thesis presents an examination of methods for estimating growth rates in American lobster and an analysis of von Bertalanffy growth parameters (growth rate and maximum size) throughout the species’ range. The goals of this project were to compare lobster growth rates in different locations and determine if latitude could be used as a predictor. Growth rates are desired in order to estimate reproductive value, a tool which can then be used to evaluate fisheries management measures. They are also required for estimates of death rates and for a yield-­‐per-­‐recruit model. The results presented here show that existing estimates of von Bertalanffy growth parameters are not comparable between studies (Chapter 2), and that new estimates of growth rates have a negative relationship with latitude (Chapter 3), meaning growth rates decrease as you go north. The decrease in growth rate per degree of latitude is approximately 0.3% for both male and female. Growth rate for American lobster can now be estimated on a site-­‐specific basis using latitude, reducing the need for resource-­‐intensive tag-­‐recapture field studies. The results also show that latitudinal variation in growth rates is largely due to latitudinal gradients in temperature (Chapter 4)

    Lobster Sustainability Measures in Newfoundland: Are They Effective?

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    The American lobster (Homarus americanus) fishery is a locally reliable inshore commercial fishery in North America with an economic value of CAD 550 million/year in Atlantic Canada. In Newfoundland, this provides 30 million/year in landed value and has considerable socio-economic value (2900 license holders) in rural communities throughout the province. The small boat lobster fishery is at once a regular source of income and part of the cultural integrity of coastal communities in Newfoundland. In recent years concern about the sustainability of this fishery has risen because the percent of harvestable lobsters taken from populations each year is at least 75% in almost all Canadian stocks and in some areas rises to over 95%. The Fisheries Research Conservation Council concluded (FRCC 2007) that in the absence of science data on lobster stocks the fate of future stocks is uncertain if lobsters continue to be harvested at recent rates. Several conservation initiatives were undertaken, with local support, to address these concerns and now form current management practice. These were closed areas [including federally designated marine protected areas (MPAs)], voluntary v-notching, a minimal landing size of 82.5 mm, and the adoption of a maximum size limit in four Lobster Fishing Areas (i.e., a slot fishery). The need for better scientific data on the effectiveness of these measures sparked the FFAW and fish harvesters in Newfoundland to collect data, contribute to the assessment of the stock, and propose a collaborative research project with Memorial University scientists in conjunction with CURRA, the Community-University Research for Recovery Alliance (www.curra.ca). With support from NSERC (Natural Science and Engineering Research Council) a 3 year project was undertaken to address questions being asked by harvesters: are these resource sustainability initiatives (v-notching, closed areas, and a slot fishery) effective?; and specifically, do these measures result in increased egg production and increased size/age distribution, which in turn increase egg production? To establish whether these measures have a science basis we used a central concept in population biology called "reproductive value" to evaluate the effectiveness of these measures. Reproductive value considers not only current egg production, it takes into account the expected future value of the individual to the population. Reproductive value allows us to compare the value of an individual as a commodity with its value to its population

    Assessing Attitudes Towards Tobacco Advertising in Winooski, VT

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    Introduction. Smoking rates are 15% in Vermont and higher in low-income populations. Winooski, Vermont is vulnerable to high tobacco use rates given that 23.6% of Winooski residents live below the poverty line. Tobacco advertising, which has been shown to have a direct, dose-dependent association with youth tobacco use, is highly prevalent in stores in Winooski.https://scholarworks.uvm.edu/comphp_gallery/1091/thumbnail.jp

    SYT1-associated neurodevelopmental disorder: a case series.

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    Synaptotagmin 1 (SYT1) is a critical mediator of fast, synchronous, calcium-dependent neurotransmitter release and also modulates synaptic vesicle endocytosis. This paper describes 11 patients with de novo heterozygous missense mutations in SYT1. All mutations alter highly conserved residues, and cluster in two regions of the SYT1 C2B domain at positions Met303 (M303K), Asp304 (D304G), Asp366 (D366E), Ile368 (I368T) and Asn371 (N371K). Phenotypic features include infantile hypotonia, congenital ophthalmic abnormalities, childhood-onset hyperkinetic movement disorders, motor stereotypies, and developmental delay varying in severity from moderate to profound. Behavioural characteristics include sleep disturbance and episodic agitation. Absence of epileptic seizures and normal orbitofrontal head circumference are important negative features. Structural MRI is unremarkable but EEG disturbance is universal, characterized by intermittent low frequency high amplitude oscillations. The functional impact of these five de novo SYT1 mutations has been assessed by expressing rat SYT1 protein containing the equivalent human variants in wild-type mouse primary hippocampal cultures. All mutant forms of SYT1 were expressed at levels approximately equal to endogenous wild-type protein, and correctly localized to nerve terminals at rest, except for SYT1M303K, which was expressed at a lower level and failed to localize at nerve terminals. Following stimulation, SYT1I368T and SYT1N371K relocalized to nerve terminals at least as efficiently as wild-type SYT1. However, SYT1D304G and SYT1D366E failed to relocalize to nerve terminals following stimulation, indicative of impairments in endocytic retrieval and trafficking of SYT1. In addition, the presence of SYT1 variants at nerve terminals induced a slowing of exocytic rate following sustained action potential stimulation. The extent of disturbance to synaptic vesicle kinetics is mirrored by the severity of the affected individuals' phenotypes, suggesting that the efficiency of SYT1-mediated neurotransmitter release is critical to cognitive development. In summary, de novo dominant SYT1 missense mutations are associated with a recognizable neurodevelopmental syndrome, and further cases can now be diagnosed based on clinical features, electrophysiological signature and mutation characteristics. Variation in phenotype severity may reflect mutation-specific impact on the diverse physiological functions of SYT1

    Performance of the CMS Cathode Strip Chambers with Cosmic Rays

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    The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

    Aligning the CMS Muon Chambers with the Muon Alignment System during an Extended Cosmic Ray Run

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    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≀0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Fair and equitable sharing of benefits from the utilization of marine genetic resources in areas beyond national jurisdiction: Bridging the gaps between science and policy

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    Marine genetic resources are a subject of a growing body of research and development activities, as demonstrated by the abundance of marine patented genes reported in GenBank. Given the lack of a comprehensive legal regime for the management of marine genetic resources in areas beyond national jurisdiction, the General Assembly of the United Nations met in 2006 to discuss whether there are regulatory or governance gaps and how to address them. Besides the crystallization of the different political positions, the process is now advancing towards making a decision about whether to develop an international instrument under the United Nations Convention on the Law of the Sea (UNCLOS) for the conservation and sustainable use of marine biological diversity, within which the regulation of access to genetic resources and the sharing of benefits from their utilization has emerged as an in-dissociable issue. In order to propose concrete options to be considered for the establishment of a legal framework addressing these issues, policy-makers need to better understand the feasibility, the costs and the modalities of scientific activities undertaken, together with the actual level of commercialization of new products. They also need to be aware of the already advanced practices in place within the scientific community, especially regarding sharing of non-monetary benefits. This paper particularly highlights and discusses practical scenarios to advance in the international process, based on the approaches adopted in other regional and international regimes for the management of genetic resources and on the best practices developed within the scientific community. © 2014 Elsevier Ltd
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