308 research outputs found

    Characterizing the nonlinear internal wave climate in the northeastern South China Sea

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    Four oceanographic moorings were deployed in the South China Sea from April 2005 to June 2006 along a transect extending from the Batanes Province, Philippines in the Luzon Strait to just north of Dong-Sha Island on the Chinese continental slope. The purpose of the array was to observe and track large-amplitude nonlinear internal waves (NIWs) from generation to shoaling over the course of one full year. The basin and slope moorings observed velocity, temperature (<i>T</i>) and salinity (<i>S</i>) at 1–3 min intervals to observe the waves without aliasing. The Luzon mooring observed velocity at 15 min and <i>T</i> and <i>S</i> at 3 min, primarily to resolve the tidal forcing in the strait. <br><br> The observed waves travelled WNW towards 282–288 degrees with little variation. They were predominantly mode-1 waves with orbital velocities exceeding 100 cm s<sup>−1</sup> and thermal displacements exceeding 100 m. Consistent with earlier authors, two types of waves were observed: the a-waves arrived diurnally and had a rank-ordered packet structure. The b-waves arrived in between, about an hour later each day similar to the pattern of the semi-diurnal tide. The b-waves were weaker than the a-waves, usually consisted of just one large wave, and were often absent in the deep basin, appearing as NIW only upon reaching the continental slope. The propagation speed of both types of waves was 323±31 cm s<sup>−1</sup> in the deep basin and 222±18 cm s<sup>−1</sup> over the continental slope. These speeds were 11–20% faster than the theoretical mode-1 wave speeds for the observed stratification, roughly consistent with the additional contribution from the nonlinear wave amplitude. The observed waves were clustered around the time of the spring tide at the presumed generation site in the Luzon Strait, and no waves were observed at neap tide. A remarkable feature was the distinct lack of waves during the winter months, December 2005 through February 2006. <br><br> Most of the features of the wave arrivals can be explained by the tidal variability in the Luzon Strait. The near-bottom tidal currents in the Luzon Strait were characterized by a large fortnightly envelope, large diurnal inequality, and stronger ebb (towards the Pacific) than flood tides. Within about ±4 days of spring tide, when currents exceeded 71 cm s<sup>−1</sup>, the ebb tides generated high-frequency motions immediately that evolved into well-developed NIWs by the time they reached mooring B1 in the deep basin. These waves formed diurnally and correspond to the a-waves described by previous authors. Also near spring tide, the weaker flood tides formed NIWs which took longer/further to form, usually not until they reached mooring S7 on the upper continental slope. These waves tracked the semidiurnal tide and correspond to the b-waves described by previous authors. These patterns were consistent from March to November. During December–February, the structure of the barotropic tide was unchanged, so the lack of waves during this time is attributed to the deep surface mixed layer and weaker stratification along the propagation path in winter

    Endoparasitic insights of free-living fin (Balaenoptera physalus), Humpback (Megaptera novaeangliae) and North Atlantic Right Whales (Eubalaena glacialis) from Eastern Canadian Waters

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    Open Access funding enabled and organized by Projekt DEAL.Purpose: To date, little is still known on parasite infections affecting free-living large whale populations worldwide. Data presented should be considered as a baseline study for future monitoring surveys on endoparasites affecting whales, thereby enhancing investigations on impacts of zoonotic parasitoses not only on vulnerable or endangered baleen whale population health but also on public health. Methods: The presented study is a first report on gastrointestinal parasites infecting different free-living baleen whales inhabiting East Canadian waters using non-invasive methods. Individual faecal samples from fin (n = 3; Balaenoptera physalus), humpback (n = 4; Megaptera novaeangliae) and North Atlantic right whales (n = 1; Eubalaena glacialis) were collected without animal disturbance, within their natural habitats on an ecological expedition during annual surveys in summer 2017. Faecal samples were assessed by standardized diagnostic methods, such as sodium acetate acetic formalin (SAF) technique, carbol fuchsin-stained faecal smears, Giardia/Cryptosporidium coproantigen ELISAs and were applied for further identification. Results: Parasitological infections included three different potentially zoonotic parasite species, one protozoa (Entamoeba spp.) and two metazoans (Diphyllobothriidae gen. sp., Ascaridida indet.). No positive Giardia/Cryptosporidium coproantigen ELISA could be found in the studied whales. Conclusion: This study adds to the current knowledge of intestinal and zoonotic parasite infections of vulnerable to partly endangered free-ranging baleen whales. Only few or no parasitological studies exist for these whale species, usually dealing with only one dead specimen. We call for more research in this field especially for the importance of conservation of free-living marine mammals using non-invasive methods.Publisher PDFPeer reviewe

    Spatio-temporal patterns in fin whale <i>Balaenoptera physalus</i> habitat use in the northern Gulf of St. Lawrence

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    Significant ecosystem changes in the Gulf of St. Lawrence (GSL), Canada, have had far-reaching effects at all trophic levels. The abundance of fin whales Balaenoptera physalus has declined significantly in the northern GSL over the past decade. This study aimed to test the hypothesis that the observed decline was correlated to changing environmental conditions. Cetacean sightings data from 292 surveys, resulting in 2986 fin whale encounters from 2007 to 2013, were used to fit 2 separate generalised additive models in terms of (1) bathymetric and oceanographic variables (the proxy model) and (2) modelled krill biomass (the prey model). The concept of ‘handling time’ was introduced to correct for time off search effort, applicable to other studies relying on opportunistically sampled data. While a positive correlation between krill biomass and fin whale numbers was found, the performance of the proxy model (24.2% deviance explained) was overall better than the prey model (11.8%). Annual predictive maps derived from the final proxy model highlighted 2 key areas with recurrently high relative fin whale abundance and a significant overlap with shipping lanes. While both models provided evidence for an annual decline in relative fin whale abundance, static bathymetric features were the most important predictors of habitat use, and no correlation between dynamic variables and the decline was found. High resolution prey data and a better understanding of the feeding ecology of fin whales are proposed to further investigate the predator-prey relationship and decline of fin whales in the GSL

    Phase IIIa-CCS: Latitudinal variation of upwelling, retention, nutrient supply and freshwater effects in the California Current System

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    US-GLOBEC NEP AbstractThis proposal requests funding to: a) synthesize the moored current meter, shore-based HF radar, ship-based hydrographic, and remotely sensed data from the GLOBEC Northeast Pacific (NEP) Long-Term Observation Program (LTOP) and related programs into a coherent, best description of the mesoscale variability along the Pacific Northwest coast from 42 to 48N; and b) relate this physical variability to primary production, zooplankton distributions, and salmon year-class strength in the region. The long-term moorings will allow quantification of the relevant time scales from internal waves to the inter-annual; the satellite images of sea surface temperature and chlorophyll will show the spatial scales; and the HF surface fields will allow timeand space-varying statistics of the mesoscale currents and quasi-Lagrangian pathways to be assessed. The primary scientific objective will be to characterize the alongshelf variability in the upwelling, the nutrients it supplies to the photic zone for utilization by marine organisms, and the retention times of plankton. This variability is affected by the alongshore distribution of the wind stress and fresh water input, by the changes in the bottom topography and coastline orientation, and by pre-conditioning established by inter-annual variability and climate change

    Statistical properties of near‐surface flow in the California coastal transition zone

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    The article of record as published may be found at https://doi.org/10.1029/91JC01072During the summers of 1987 and 1988, 77 near-surface satellite-tracked drifters were deployed in or near cold filaments near Point Arena, California (39°N), and tracked for up to 6 months as part of the Coastal Transition Zone (CTZ) program. The drifters had large drogues centered at 15 m, and the resulting drifter trajectory data set has been analyzed in terms of its Eulerian and Lagrangian statistics. The CTZ drifter results show that the California Current can be characterized in summer and fall as a meandering coherent jet which on average flows southward to at least 30°N, the southern end of the study domain. From 39°N south to about 33°N, the typical core velocities are of O(50 cm s−1) and the current meanders have alongshore wavelengths of O (300 km) and onshore-offshore amplitude of O(100–200 km). The lateral movement of this jet leads to large eddy kinetic energies and large eddy diffusivities, especially north of 36°N. The initial onshore-offshore component of diffusivity is always greater than the alongshore component in the study domain, but at the southern end, the eddy diffusivity is more isotropic, with scalar single particle diffusivity (Kxx + Kyy) of O(8 × 107 cm2 s−1). The eddy diffusivity increases with increasing eddy energy. Finally, a simple volume budget for the 1988 filament observed near 37°N off Point Arena suggests that subduction can occur in a filament at an average rate of O (10 m d−1) some 200 km offshore, thus allowing the cold water initially in the filament core to sink below the warmer ambient water by the time the surface velocity core has turned back onshore. This process explains why satellite temperature and color imagery tend to “see” only flow proceeding offshore

    Psychological distress and lower health-related quality of life are associated with need for dietary support among colorectal cancer survivors with overweight or obesity

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    Objective: Two-third of colorectal cancer (CRC) survivors are overweight or obese. Psychological distress and low health-related quality of life (HRQoL) may be barriers to improving diet. We aimed to assess associations between psychological distress and HRQoL and the need for dietary support in CRC survivors with overweight or obesity. Methods: All alive individuals diagnosed with CRC between 2000 and 2009, as registered by the Dutch population-based Eindhoven Cancer Registry, were eligible for participation and received a questionnaire. Multivariable logistic regression analyses were conducted to assess associations between HRQoL (EORTC QLQ-C30), symptoms of anxiety and depression (HADS), and self-reported need for dietary support (single-item). Results: A total of 1458 completed the questionnaire (response rate 82%), and 756 (43%) had a BMI of 25.0 or higher and complete data on “need for dietary support” and were included for analyses. BMI ranged between 25.0 and 60.6 (mean, 28.9; SD, 3.6). The majority (71.7%) was overweight (BMI ≄ 25), and 28.3% obese (BMI ≄ 30). Twenty-one percent reported a need for dietary support which was associated with more psychological distress and lower HRQoL. Those who experienced symptoms of anxiety or depression were more likely to report a need for dietary support (27.6% and 28.7%) than those who did not experience symptoms of anxiety (12.3%; OR 2.02; 95% CI 1.22–3.35) or depression (13.5%; OR 1.96; 95% CI 1.19–3.22). Conclusions: Results suggest that psychological distress and lower HRQoL should be taken into account while promoting a healthy diet in overweight or obese CRC survivors since these factors may hinder adherence to a healthy diet.</p

    Examining the Skill Gap in Fashion Education

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    This research explores the importance of sewing skills within HE fashion education. Recent literature has identified significant discussion concerning a graduate skills gap at the onset of employment. Some industry specialists fear that educators are not doing enough to promote the technical side of fashion. As a consequence, there are concerns of a widening gap in the uptake of technical job roles within the fashion sector. This research investigates potential reasons why students might not make these career choices, focusing mainly on the teaching of construction skills through the development of a resource tool to enhance the curriculum to bridge this recognised gap. To contextualise the development of this project, literature has examined key areas of interest. These include studies relating to skill gaps, manufacture and production techniques as well as the relationship between technical skill and career interests. This research has applied a variety of methodologies, which have explored the skills required for fundamental sewing processes, the value of sewing from educational and industry perspectives and issues relating to the recognised skills gap and career choices. Methods have included object-based study, interviews with manufacturers and a focus group with second year BA (Hons) fashion design students undertaking pattern cutting and manufacture sessions. To evaluate the effectiveness of the resource tool of stitch and garment finishing techniques, questionnaires, observations and examinations were conducted with undergraduate students undertaking sewing sessions. This research has revealed that the resource tool was successful in engaging students with garment construction techniques, and that this was most beneficial when used in conjunction with other methods. During testing it was apparent that students preferred to work more creatively, using inventiveness over memory of previously taught sewing skills when producing samples. Interestingly, the research has also highlighted two distinctions; that further technical knowledge in sewing appears to, in some instances, have limited the creativity of students’ fashion design outcomes when advancing from a foundation to intermediate level of study. However, there is also evidence to suggest that further engagement with sewing had a positive influence on their understanding of garment construction informing feasible design. There appears to be minimal evidence that links strong sewing skill with the ambition to choose careers in the manufacturing sector. The conclusions from this research, including the testing results from the resource tool, support the development of a technical curriculum within the BA curriculum, and the development of a qualification level prior to BA

    Direct estimation of genome mutation rates from pedigrees in free-ranging baleen whales

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    Current low germline mutation rate (&#x1d707;) estimates in baleen whales have greatly influenced research ranging from assessments of whaling impacts to evolutionary cancer biology. However, the reported rates were subject to methodological errors and uncertainty. We estimated &#x1d707; directly from pedigrees in natural populations of four baleen whale species and the results were similar to primates. The implications of revised &#x1d707; values include pre-exploitation population sizes at 14% of previous genetic diversity-based estimates and the conclusion that &#x1d707; in itself is insufficient to explain low cancer rates in gigantic mammals (i.e., Peto’s Paradox). We demonstrate the feasibility of estimating &#x1d707; from whole genome pedigree data in natural populations, which has wide-ranging implications for the many ecological and evolutionary inferences that rely on &#x1d707;

    Disturbed balance of expression between XIAP and Smac/DIABLO during tumour progression in renal cell carcinomas

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    Dysregulation of apoptosis plays an important role in tumour progression and resistance to chemotherapy. The X-linked inhibitor of apoptosis ( XIAP) is considered to be the most potent caspase inhibitor of all known inhibitor of apoptosis-family members. Only recently, an antagonist of XIAP has been identified, termed Smac/DIABLO. To explore the relevance of antiapoptotic XIAP and proapoptotic Smac/DIABLO for tumour progression in renal cell carcinomas (RCCs), we analysed XIAP and Smac/DIABLO mRNA and protein expression in the primary tumour tissue from 66 RCCs of all major histological types by quantitative real-time PCR, Western blot and ELISA. X-linked inhibitor of apoptosis and Smac/DIABLO mRNA expression was found in all RCCs. Importantly, the relative XIAP mRNA expression levels significantly increased from early (pT1) to advanced (pT3) tumour stages ( P = 0.0002) and also with tumour dedifferentiation ( P = 0.04). Western blot analysis confirmed the tumour stage-dependent increase of XIAP expression on the protein level. In contrast, mRNA and protein expression levels of Smac/DIABLO did not significantly change between early and advanced tumour stages or between low and high tumour grades. Consequently, the mRNA expression ratio between antiapoptotic XIAP and proapoptotic Smac/DIABLO markedly increased during progression from early ( pT1) to advanced ( pT3) tumour stages. Moreover, RCCs confined within the organ capsule ( pT1 and pT2) exhibited a significantly lower XIAP to Smac/DIABLO expression ratio when compared with RCCs infiltrating beyond the kidney ( pT3; P = 0.01). Thus, our investigation demonstrates that the delicate balance between XIAP and Smac/DIABLO expression is gradually disturbed during progression of RCCs, resulting in a relative increase of antiapoptotic XIAP over proapoptotic Smac/DIABLO, thereby probably contributing to the marked apoptosis resistance of RCC.OncologySCI(E)46ARTICLE71349-13579
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