125 research outputs found

    Eye spectral sensitivity in fresh- and brackish-water populations of three glacial-relict Mysis species (Crustacea) : physiology and genetics of differential tuning

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    Absorbance spectra of single rhabdoms were studied by microspectrophotometry (MSP) and spectral sensitivities of whole eyes by electroretinography (ERG) in three glacial-relict species of opossum shrimps (Mysis). Among eight populations from Fennoscandian fresh-water lakes (L) and seven populations from the brackish-water Baltic Sea (S), L spectra were systematically red-shifted by 20-30 nm compared with S spectra, save for one L and one S population. The difference holds across species and bears no consistent adaptive relation to the current light environments. In the most extensively studied L-S pair, two populations of M. relicta (L (p) and S (p)) separated for less than 10,000 years, no differences translating into amino acid substitutions have been found in the opsin genes, and the chromophore of the visual pigments as analyzed by HPLC is pure A1. However, MSP experiments with spectrally selective bleaching show the presence of two rhodopsins (lambda (max) a parts per thousand 525-530 nm, MWS, and 565-570 nm, LWS) expressed in different proportions. ERG recordings of responses to "red" and "blue" light linearly polarized at orthogonal angles indicate segregation of the pigments into different cells differing in polarization sensitivity. We propose that the pattern of development of LWS and MWS photoreceptors is governed by an ontogenetic switch responsive to some environmental signal(s) other than light that generally differ(s) between lakes and sea, and that this reaction norm is conserved from a common ancestor of all three species.Peer reviewe

    Dark‑adaptation in the eyes of a lake and a sea population of opossum shrimp (Mysis relicta): retinoid isomer dynamics, rhodopsin regeneration, and recovery of light sensitivity

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    We have studied dark-adaptation at three levels in the eyes of the crustaceanMysis relictaover 2-3 weeks after exposing initially dark-adapted animals to strong white light: regeneration of 11-cisretinal through the retinoid cycle (by HPLC), restoration of native rhodopsin in photoreceptor membranes (by MSP), and recovery of eye photosensitivity (by ERG). We compare two model populations ("Sea", S-p, and "Lake", L-p) inhabiting, respectively, a low light and an extremely dark environment. 11-cisretinal reached 60-70% of the pre-exposure levels after 2 weeks in darkness in both populations. The only significant L-p/S(p)difference in the retinoid cycle was that L(p)had much higher levels of retinol, both basal and light-released. In S-p, rhodopsin restoration and eye photoresponse recovery parallelled 11-cisretinal regeneration. In L-p, however, even after 3 weeks only ca. 25% of the rhabdoms studied had incorporated new rhodopsin, and eye photosensitivity showed only incipient recovery from severe depression. The absorbance spectra of the majority of the L(p)rhabdoms stayed constant around 490-500 nm, consistent with metarhodopsin II dominance. We conclude that sensitivity recovery of S(p)eyes was rate-limited by the regeneration of 11-cisretinal, whilst that of L(p)eyes was limited by inertia in photoreceptor membrane turnover.Peer reviewe

    Physiotherapy practices and third party payers: issues in professional ethics in the Atlantic provinces

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    [À l'origine dans / Was originally part of : ESPUM - Dép. médecine sociale et préventive - Travaux et publications]During a 4-month period, July 2nd 2014 to November 1st 2014, Canadian physiotherapy (PT) professionals were solicited for participation in an empirical cross-sectional online survey questionnaire. Our research team was interested in exploring the ethical challenges encountered in the interactions between PT professionals and third party payers. Analysis of the survey will be disseminated through scientific publications. The purpose of this report is to give detailed results relevant to your provincial association.Canadian Arthritis Network (CAN), Canadian Institutes of Health Research (CIHR), Fonds de recherche du Québec-Santé (FRQ-S), Quebec Research Rehabilitation Network (REPAR

    Physiotherapy practices and third party payers: issues in professional ethics in the Prairie provinces

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    [À l'origine dans / Was originally part of : ESPUM - Dép. médecine sociale et préventive - Travaux et publications]During a 4-month period, July 2nd 2014 to November 1st 2014, Canadian physiotherapy (PT) professionals were solicited for participation in an empirical cross-sectional online survey questionnaire. Our research team was interested in exploring the ethical challenges encountered in the interactions between PT professionals and third party payers. Analysis of the survey will be disseminated through scientific publications. The purpose of this report is to give detailed results relevant to your provincial association.Canadian Arthritis Network (CAN), Canadian Institutes of Health Research (CIHR), Fonds de recherche du Québec-Santé (FRQ-S), Quebec Research Rehabilitation Network (REPAR

    Physiotherapy practices and third party payers: issues in professional ethics in Quebec

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    [À l'origine dans / Was originally part of : ESPUM - Dép. médecine sociale et préventive - Travaux et publications]During a 4-month period, July 2nd 2014 to November 1st 2014, Canadian physiotherapy (PT) professionals were solicited for participation in an empirical cross-sectional online survey questionnaire. Our research team was interested in exploring the ethical challenges encountered in the interactions between PT professionals and third party payers. Analysis of the survey will be disseminated through scientific publications. The purpose of this report is to give detailed results relevant to your provincial association.Canadian Arthritis Network (CAN), Canadian Institutes of Health Research (CIHR), Fonds de recherche du Québec-Santé (FRQ-S), Quebec Research Rehabilitation Network (REPAR

    Physiotherapy practices and third party payers: issues in professional ethics in Ontario

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    [À l'origine dans / Was originally part of : ESPUM - Dép. médecine sociale et préventive - Travaux et publications]During a 4-month period, July 2nd 2014 to November 1st 2014, Canadian physiotherapy (PT) professionals were solicited for participation in an empirical cross-sectional online survey questionnaire. Our research team was interested in exploring the ethical challenges encountered in the interactions between PT professionals and third party payers. Analysis of the survey will be disseminated through scientific publications. The purpose of this report is to give detailed results relevant to your provincial association.Canadian Arthritis Network (CAN), Canadian Institutes of Health Research (CIHR), Fonds de recherche du Québec-Santé (FRQ-S), Quebec Research Rehabilitation Network (REPAR

    Early life metal dysregulation in amyotrophic lateral sclerosis

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    ObjectiveDeficiencies and excess of essential elements and toxic metals are implicated in amyotrophic lateral sclerosis (ALS), but the age when metal dysregulation appears remains unknown. This study aims to determine whether metal uptake is dysregulated during childhood in individuals eventually diagnosed with ALS.MethodsLaser ablation- inductively coupled plasma- mass spectrometry was used to obtain time series data of metal uptake using biomarkers in teeth from autopsies or dental extractions of ALS (n = 36) and control (n = 31) participants. Covariate data included sex, smoking, occupational exposures, and ALS family history. Case- control differences were identified in temporal profiles of metal uptake for individual metals using distributed lag models. Weighted quantile sum (WQS) regression was used for metals mixture analyses. Similar analyses were performed on an ALS mouse model to further verify the relevance of dysregulation of metals in ALS.ResultsMetal levels were higher in cases than in controls: 1.49 times for chromium (1.11- 1.82; at 15 years), 1.82 times for manganese (1.34- 2.46; at birth), 1.65 times for nickel (1.22- 2.01; at 8 years), 2.46 times for tin (1.65- 3.30; at 2 years), and 2.46 times for zinc (1.49- 3.67; at 6 years). Co- exposure to 11 elements indicated that childhood metal dysregulation was associated with ALS. The mixture contribution of metals to disease outcome was likewise apparent in tooth biomarkers of an ALS mouse model, and differences in metal distribution were evident in ALS mouse brains compared to brains from littermate controls.InterpretationOverall, our study reveals direct evidence that altered metal uptake during specific early life time windows is associated with adult- onset ALS.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155978/1/acn351006_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155978/2/acn351006.pd

    Engaging More Effectively With Visitors to Coastal Regions for Improved Management Outcomes: Insights From the Ningaloo Coast, Australia

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    A key component of successful coastal management efforts is an effective communication and engagement strategy focused on raising awareness of a region to different stakeholders to encourage more pro-environmental behaviors. Accordingly, in recent times there has been a proliferation of research focused on improving engagement and communication with different users of the coastal environment. Despite this effort, a paucity of evidence is available to guide better communication and engagement with visitors (i.e., tourists). Addressing this knowledge gap is critical given the adverse impacts of current global coastal tourism on ecosystem health, and projected future increases in coastal tourism. Using a case study of the Ningaloo Coast World Heritage Area (WHA) in Australia, we contribute toward filling this gap by identifying visitors’ perception of the region and their self-reported and intended proenvironmental behaviors. We also identify the types of information they access and trust, and explore whether different message framings on the value of the WHA influence visitors’ intended pro-environmental behavior. We determine that although visitors to the Ningaloo Coast WHA are optimistic about the future sustainability of the region, they have low understanding of the rules and regulations in place to support its management. Further, we find that visitors consider tourism to be a serious threat to the future of the region. However, most participants in our study considered the quality of their own environmental behavior to be high, and thus not contributing to these threats, although this did differ by gender. Finally, we highlight that visitors to the Ningaloo Coast WHA, for the most part, obtain their knowledge of the region during their visit, primarily through local signage and visitors centers. We discuss the implications of these results, and highlight future considerations for coastal managers when developing visitor-focused communication and engagement strategies
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