247 research outputs found

    Coral skeleton P/Ca proxy for seawater phosphate: Multi-colony calibration with a contemporaneous seawater phosphate record

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    A geochemical proxy for surface ocean nutrient concentrations recorded in coral skeleton could provide new insight into the connections between sub-seasonal to centennial scale nutrient dynamics, ocean physics, and primary production in the past. Previous work showed that coralline P/Ca, a novel seawater phosphate proxy, varies synchronously with annual upwelling-driven cycles in surface water phosphate concentration. However, paired contemporaneous seawater phosphate time-series data, needed for rigorous calibration of the new proxy, were lacking. Here we present further development of the P/Ca proxy in Porites lutea and Montastrea sp. corals, showing that skeletal P/Ca in colonies from geographically distinct oceanic nutrient regimes is a linear function of seawater phosphate (PO4 SW) concentration. Further, high-resolution P/Ca records in multiple colonies of Pavona gigantea and Porites lobata corals grown at the same upwelling location in the Gulf of Panama were strongly correlated to a contemporaneous time-series record of surface water PO4 SW at this site (r2 = 0.7–0.9). This study supports application of the following multi-colony calibration equations to down-core records from comparable upwelling sites, resulting in ±0.2 and ±0.1 lmol/kg uncertainties in PO4 SW reconstructions from P. lobata and P. gigantea, respectively.P/Ca Porites lobata (lmol/mol) = (21.1 ? 2.4)PO4 SW (lmol/kg) + (14.3 ? 3.8)P/Ca Pavona gigantea (lmol/mol) = (29.2 ? 1.4)PO4 SW (lmol/kg) + (33.4 ? 2.7)Inter-colony agreement in P/Ca response to PO4 SW was good (±5–12% about mean calibration slope), suggesting that species-specific calibration slopes can be applied to new coral P/Ca records to reconstruct past changes in surface ocean phosphate. However, offsets in the y-intercepts of calibration regressions among co-located individuals and taxa suggest that biologically-regulated “vital effects” and/or skeletal extension rate may also affect skeletal P incorporation. Quantification of the effect of skeletal extension rate on P/Ca could lead to corrected calibration equations and improved inter-colony P/Ca agreement. Nevertheless, the efficacy of the P/Ca proxy is thus supported by both broad scale correlation to mean surface water phosphate and regional calibration against documented local seawater phosphate variations

    Public perceptions of drinking water: A postal survey of residents with private water supplies

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    Background: In Canada, the legal responsibility for the condition of private water supplies, including private wells and cisterns, rests with their owners. However, there are reports that Canadians test these water supplies intermittently and that treatment of such water is uncommon. An estimated 45% of all waterborne outbreaks in Canada involve non-municipal systems. An understanding of the perceptions and needs of Canadians served by private water supplies is essential, as it would enable public health professionals to better target public education and drinking water policy. The purpose of this study was to investigate the public perceptions of private water supplies in the City of Hamilton, Ontario (Canada), with the intent of informing public education and outreach strategies within the population. Methods: A cross-sectional postal survey of 246 residences with private water supplies was conducted in May 2004. Questions pertained to the perceptions of water quality and alternative water sources, water testing behaviours and the self-identified need for further information. Results: Private wells, cisterns or both, were the source of household water for 71%, 16% and 13% of respondents, respectively. Although respondents rated their water quality highly, 80% also had concerns with its safety. The most common concerns pertained to bacterial and chemical contamination of their water supply and its potential negative effect on health. Approximately 56% and 61% of respondents used in-home treatment devices and bottled water within their homes, respectively, mainly due to perceived improvements in the safety and aesthetic qualities compared to regular tap water. Testing of private water supplies was performed infrequently: 8% of respondents tested at a frequency that meets current provincial guidelines. Two-thirds of respondents wanted more information on various topics related to private water supplies. Flyers and newspapers were the two media reported most likely to be used. Conclusion: Although respondents rated their water quality highly, the majority had concerns regarding the water from their private supply, and the use of bottled water and water treatment devices was extensive. The results of this study suggest important lines of inquiry and provide support and input for public education programs, particularly those related to private water testing, in this population

    Pre-treatment effects on coral skeletal delta\u3csup\u3e13\u3c/sup\u3eC and delta\u3csup\u3e18\u3c/sup\u3eO

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    Pre-treatments are often used to remove organic “contaminant” material prior to isotopic analyses of coral skeletal samples. Here we conducted three experiments to test the pre-treatment effect of water, 30% hydrogen peroxide (H2O2), and household bleach [5.25% sodium hypochlorite (NaClO3) and 0.15% sodium hydroxide (NaOH)], on the stable isotopic composition of coral skeletal samples. First, using a mass balance approach we calculated the expected change in skeletal delta13C due to the removal of all organic carbon. The model showed that (1) the removal of organic carbon (which has a low delta13C value relative to skeletal delta13C) from the skeletal sample should theoretically result in a higher delta13C value of the remaining organic-carbon-free carbonate, and that (2) only at the highest concentrations of skeletal organic carbon within the tissue layer of corals is the contribution of the organic carbon to the overall delta13C skeletal value potentially large enough to be detectable by mass spectrometry. We then conducted two sets of experiments to test the model where we pre-treated a large number of skeletal samples from five species of corals with water, H2O2, bleach, or no pre-treatment for 24 h. Skeletal delta13C generally decreased significantly with water, bleach, and H2O2 pre-treatments which is contrary to the model-predicted increase in delta13C following such pre-treatments. Thus, organic carbon within the skeleton is not a net source of contamination to delta13C analyses. Skeletal delta18O decreased the most with water and bleach pre-treatments. In addition, the effect of H2O2 or bleach pre-treatments on either delta13C or delta18O was not consistent among species or locations. The direction of change in delta13C and delta18O with pre-treatments was no different for skeletal samples taken within or below the tissue layer. Based on our results, we suggest that pre-treatment is not necessary and recommend that pre-treatment not be performed on coral skeletal samples prior to stable isotope analysis to avoid any pre-treatment-induced variability that could significantly compromise inter-colony and inter-species comparisons

    Anticoagulant rodenticides on our public and community lands: spatial distribution of exposure and poisoning of a rare forest carnivore.

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    Anticoagulant rodenticide (AR) poisoning has emerged as a significant concern for conservation and management of non-target wildlife. The purpose for these toxicants is to suppress pest populations in agricultural or urban settings. The potential of direct and indirect exposures and illicit use of ARs on public and community forest lands have recently raised concern for fishers (Martes pennanti), a candidate for listing under the federal Endangered Species Act in the Pacific states. In an investigation of threats to fisher population persistence in the two isolated California populations, we investigate the magnitude of this previously undocumented threat to fishers, we tested 58 carcasses for the presence and quantification of ARs, conducted spatial analysis of exposed fishers in an effort to identify potential point sources of AR, and identified fishers that died directly due to AR poisoning. We found 46 of 58 (79%) fishers exposed to an AR with 96% of those individuals having been exposed to one or more second-generation AR compounds. No spatial clustering of AR exposure was detected and the spatial distribution of exposure suggests that AR contamination is widespread within the fisher's range in California, which encompasses mostly public forest and park lands Additionally, we diagnosed four fisher deaths, including a lactating female, that were directly attributed to AR toxicosis and documented the first neonatal or milk transfer of an AR to an altricial fisher kit. These ARs, which some are acutely toxic, pose both a direct mortality or fitness risk to fishers, and a significant indirect risk to these isolated populations. Future research should be directed towards investigating risks to prey populations fishers are dependent on, exposure in other rare forest carnivores, and potential AR point sources such as illegal marijuana cultivation in the range of fishers on California public lands

    Lake Whatcom Monitoring Project 2021/2022 Report

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    This report describes the results from the 2021/2022 Lake Whatcom monitoring program conducted by the Institute for Watershed Studies at Western Washington University (www.wwu.edu/iws). The major objectives in 2021/2022 were to continue long-term baseline water quality monitoring in Lake Whatcom and its major tributaries; collect storm runoff water quality data from representative streams in the watershed; and continue collection of hydrologic data from Austin and Smith Creeks

    Patterns of Natural and Human-Caused Mortality Factors of a Rare Forest Carnivore, the Fisher (Pekania pennanti) in California.

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    Wildlife populations of conservation concern are limited in distribution, population size and persistence by various factors, including mortality. The fisher (Pekania pennanti), a North American mid-sized carnivore whose range in the western Pacific United States has retracted considerably in the past century, was proposed for threatened status protection in late 2014 under the United States Endangered Species Act by the United States Fish and Wildlife Service in its West Coast Distinct Population Segment. We investigated mortality in 167 fishers from two genetically and geographically distinct sub-populations in California within this West Coast Distinct Population Segment using a combination of gross necropsy, histology, toxicology and molecular methods. Overall, predation (70%), natural disease (16%), toxicant poisoning (10%) and, less commonly, vehicular strike (2%) and other anthropogenic causes (2%) were causes of mortality observed. We documented both an increase in mortality to (57% increase) and exposure (6%) from pesticides in fishers in just the past three years, highlighting further that toxicants from marijuana cultivation still pose a threat. Additionally, exposure to multiple rodenticides significantly increased the likelihood of mortality from rodenticide poisoning. Poisoning was significantly more common in male than female fishers and was 7 times more likely than disease to kill males. Based on necropsy findings, suspected causes of mortality based on field evidence alone tended to underestimate the frequency of disease-related mortalities. This study is the first comprehensive investigation of mortality causes of fishers and provides essential information to assist in the conservation of this species

    What to do about Inequality? Support for the European Union and Further European Integration in the Republic of Ireland

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    This paper investigates individual’s perceptions of inequality and the impact this has on mass public opinion support for the European Union (EU) in the Republic of Ireland. This question is posed in the context of the onset of the economic and financial crisis of 2007/8 as the crisis can be regarded as a critical juncture in Ireland’s relationship with the EU as a result of the economic downturn and the widening of economic disparities individuals have experienced. Ireland is a critical case in examining EU support as since its accession to the EU in 1973 it is often considered an exemplar of what the EU could offer small member states with a strongly pro-integrationist mass public. Using Ordinary Least Squares (OLS) multiple regression analysis on 2009 European Election Study (EES) data, this paper shows that individuals’ concerns about inequality lowers support for the EU as it is currently constituted, but increases support for continued European integration. This suggests that individual-levels of support may be in a precarious state, yet they can be salvaged as individuals in Ireland regard the EU as the institutional-driving force to address market-generated inequality

    Implementation facilitation to introduce and support emergency department-initiated buprenorphine for opioid use disorder in high need, low resource settings: protocol for multi-site implementation-feasibility study

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    Background: For many reasons, the emergency department (ED) is a critical venue to initiate OUD interventions. The prevailing culture of the ED has been that substance use disorders are non-emergent conditions better addressed outside the ED where resources are less constrained. This study, its rapid funding mechanism, and accelerated timeline originated out of the urgent need to learn whether ED-initiated buprenorphine (BUP) with referral for treatment of OUD is generalizable, as well as to develop strategies to facilitate its adoption across a variety of ED settings and under real-world conditions. It both complements and uses methods adapted from Project ED Health (CTN-0069), a Hybrid Type 3 implementation-effectiveness study of using Implementation Facilitation (IF) to integrate ED-initiated BUP and referral programs. Methods: ED-CONNECT (CTN 0079) was a three-site implementation study exploring the feasibility, acceptability, and impact of introducing ED-initiated BUP in rural and urban settings with high-need, limited resources, and different staffing structures. We used a multi-faceted approach to develop, introduce and iteratively refine site-specific ED clinical protocols and implementation plans for opioid use disorder (OUD) screening, ED-initiated BUP, and referral for treatment. We employed a participatory action research approach and use mixed methods incorporating data derived from abstraction of medical records and administrative data, assessments of recruited ED patient-participants, and both qualitative and quantitative inquiry involving staff from the ED and community, patients, and other stakeholders. Discussion: This study was designed to provide the necessary, time-sensitive understanding of how to identify OUD and initiate treatment with BUP in the EDs previously not providing ED-initiated BUP, in communities in which this intervention is most needed: high need, low resource settings. Trial registration: The study was prospectively registered on ClinicalTrials.gov (NCT03544112) on June 01, 2018: https://clinicaltrials.gov/ct2/show/NCT03544112

    Neuropathological correlates of dementia in over-80-year-old brain donors from the population-based Cambridge city over-75s cohort (CC75C) study.

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    Key neuropathological changes associated with late-onset dementia are not fully understood. Population-based longitudinal studies offer an opportunity to step back and examine which pathological indices best link to clinical state. CC75C is a longitudinal study of the population aged 75 and over at baseline in Cambridge, UK. We report on the first 213 participants coming to autopsy with sufficient information for an end of life dementia diagnosis. Clinical diagnosis was ascertained by examining retrospective informant interviews, survey responses, and death certificates according to DSM-IV criteria. The neuropathological protocol was based on the Consortium to Establish a Registry of Alzheimer's Disease (CERAD). Clinical dementia was present in 113 participants (53%): 67% with Alzheimer's disease, 4% vascular dementia, 22% mixed dementia, and 1% dementia with Lewy bodies. As Alzheimer-type pathology was common, the mutually blinded clinical and neuropathological diagnoses were not strongly related. Multivariable analysis identified associations between dementia during life and entorhinal cortex neuritic plaques, hippocampal diffuse plaques, neocortical neurofibrillary tangles, white matter pallor, Lewy bodies, and hippocampal atrophy. These results were consistent in those with clinical Alzheimer's disease. Vascular pathologies, especially microinfarcts, were more common in those with clinical diagnoses including vascular dementia. Alzheimer-type and cerebrovascular pathology are both common in the very old. A greater burden of these pathologies, Lewy bodies, and hippocampal atrophy, are associated with a higher risk of, but do not define, clinical dementia in old age

    Spectroscopy, MOST Photometry, and Interferometry of MWC 314: Is it an LBV or an interacting binary?

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    MWC 314 is a bright candidate luminous blue variable that resides in a fairly close binary system, with an orbital period of 60.753±\pm0.003 d. We observed MWC 314 with a combination of optical spectroscopy, broad-band ground- and space-based photometry, as well as with long baseline, near-infrared interferometry. We have revised the single-lined spectroscopic orbit and explored the photometric variability. The orbital light curve displays two minima each orbit that can be partially explained in terms of the tidal distortion of the primary that occurs around the time of periastron. The emission lines in the system are often double-peaked and stationary in their kinematics, indicative of a circumbinary disc. We find that the stellar wind or circumbinary disc is partially resolved in the K\prime-band with the longest baselines of the CHARA Array. From this analysis, we provide a simple, qualitative model in an attempt to explain the observations. From the assumption of Roche Lobe overflow and tidal synchronisation at periastron, we estimate the component masses to be M1 5\approx 5 M_\odot and M215\approx 15 M_\odot, which indicates a mass of the LBV that is extremely low. In addition to the orbital modulation, we discovered two pulsational modes with the MOST satellite. These modes are easily supported by a low-mass hydrogen-poor star, but cannot be easily supported by a star with the parameters of an LBV. The combination of these results provides evidence that the primary star was likely never a normal LBV, but rather is the product of binary interactions. As such, this system presents opportunities for studying mass-transfer and binary evolution with many observational techniques.Comment: 26 pages, 7 figures, 5 tables, 2 appendices with 7 additional tables and 2 additional figures. Accepted for publication in MNRA
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