scholarly journals Stable isotopes reveal age-dependent trophic level and spatial segregation during adult marine feeding in populations of salmon

2012 ◽  
Vol 69 (9) ◽  
pp. 1637-1645 ◽  
Author(s):  
Kirsteen M. MacKenzie ◽  
Clive N. Trueman ◽  
Martin R. Palmer ◽  
Andy Moore ◽  
Anton T. Ibbotson ◽  
...  
Keyword(s):  
Stable Isotopes ◽  
Trophic Level ◽  
Tissue Growth ◽  
Spatial Segregation ◽  
Fish Feeding ◽  
Novel Approach ◽  
Age Dependent ◽  
And Migration ◽  
The Uk ◽  
Management And Conservation

Abstract MacKenzie, K. M., Trueman, C. N., Palmer, M. R., Moore, A., Ibbotson, A. T., Beaumont, W. R. C., and Davidson, I. C. 2012. Stable isotopes reveal age-dependent trophic level and spatial segregation during adult marine feeding in populations of salmon from the UK. – ICES Journal of Marine Science, 69: 1637–1645. Locating and differentiating the marine feeding areas used by adult salmon (Salmo salar) is essential to stock-based management and conservation, but traditional tagging studies are limited and influenced by the uneven distribution of the fisheries or research vessel surveys. Here, a novel approach is used, based on the observation that the isotopic composition of animal tissues is intrinsically linked to the environmental conditions during tissue growth, which allows for the distinction of pelagic fish feeding in different locations. This isotopic approach is applied using archived collections of salmon scales and shows that (i) salmon act as size-structured pelagic predators, (ii) adult salmon from different natal origins within the UK (and hence components of the southern European stock complex) feed in different oceanic regions before their return, (iii) one-sea-winter (1SW) and multi-sea-winter salmon returning to some rivers in the UK are separated in their marine feeding areas, whereas those from others are not, and (iv) salmon from the rivers sampled are not feeding in regions of the Northwest Atlantic used by 1SW salmon returning to rivers in Newfoundland. Therefore, the stable isotope approach allows for retrospective investigations of marine diet, location, and migration at stock- and cohort-specific levels.

Relationship between morphometrics and trophic levels in deep-sea fishes

2020 ◽  
Vol 637 ◽  
pp. 225-235 ◽  
Author(s):  
MA Ladds ◽  
MH Pinkerton ◽  
E Jones ◽  
LM Durante ◽  
MR Dunn
Keyword(s):  
Stable Isotopes ◽  
Trophic Level ◽  
Deep Sea ◽  
Strong Relationship ◽  
Ecosystem Model ◽  
Trophic Levels ◽  
Fish Size ◽  
Wide Range ◽  
Gape Size ◽  
Morphological Variables

Marine food webs are structured, in part, by predator gape size. Species found in deep-sea environments may have evolved such that they can consume prey of a wide range of sizes, to maximise resource intake in a low-productivity ecosystem. Estimates of gape size are central to some types of ecosystem model that determine which prey are available to predators, but cannot always be measured directly. Deep-sea species are hypothesized to have larger gape sizes than shallower-water species relative to their body size and, because of pronounced adaptive foraging behaviour, show only a weak relationship between gape size and trophic level. Here we present new data describing selective morphological measurements and gape sizes of 134 osteichthyan and chondrichthyan species from the deep sea (200-1300 m) off New Zealand. We describe how gape size (height, width and area) varied with factors including fish size, taxonomy (class and order within a class) and trophic level estimated from stable isotopes. For deep-sea species, there was a strong relationship between gape size and fish size, better predicted by body mass than total length, which varied by taxonomic group. Results show that predictions of gape size can be made from commonly measured morphological variables. No relationship between gape size and trophic level was found, likely a reflection of using trophic level estimates from stable isotopes as opposed to the commonly used estimates from FishBase. These results support the hypothesis that deep-sea fish are generalists within their environment, including suspected scavenging, even at the highest trophic levels.

Identity Politics and Migration

2008 ◽  
Vol 17 (1) ◽  
pp. 155-158
Author(s):  
Vytis Čiubrinskas
Keyword(s):  
National Identity ◽  
Identity Politics ◽  
Host Country ◽  
Social Anthropology ◽  
The Us ◽  
And Migration ◽  
The Uk ◽  
A Current ◽  
Respective Host

The Centre of Social Anthropology (CSA) at Vytautas Magnus University (VMU) in Kaunas has coordinated projects on this, including a current project on 'Retention of Lithuanian Identity under Conditions of Europeanisation and Globalisation: Patterns of Lithuanian-ness in Response to Identity Politics in Ireland, Norway, Spain, the UK and the US'. This has been designed as a multidisciplinary project. The actual expressions of identity politics of migrant, 'diasporic' or displaced identity of Lithuanian immigrants in their respective host country are being examined alongside with the national identity politics of those countries.

Measurement of the trophic level of fish in a coral reef ecosystem using stable isotopes

2013 ◽  
Vol 19 (1) ◽  
pp. 105-115 ◽  
Author(s):  
Guohuan YANG ◽  
Xingli SUN ◽  
Xiuqiong HOU ◽  
Chunliang CHEN
Keyword(s):  
Stable Isotopes ◽  
Coral Reef ◽  
Trophic Level ◽  
Coral Reef Ecosystem ◽  
Reef Ecosystem

Prioritizing strain insulators for raptor conservation

2021 ◽  
pp. 1-16
Author(s):  
FRANCISCO GUIL ◽  
M. ÁNGELES SORIA ◽  
VÍCTOR ORTEGA ◽  
RUBÉN GARCÍA-SÁNCHEZ ◽  
SILVIA VILLAVERDE-MORCILLO
Keyword(s):  
Methodological Approach ◽  
Risk Index ◽  
Influential Factors ◽  
Negative Effects ◽  
Central Spain ◽  
Novel Approach ◽  
Conservation Actions ◽  
Complete Survey ◽  
Raptor Conservation ◽  
Management And Conservation

Summary Avian species often take advantage of human-made structures, such as perching on power poles, although this can lead to negative effects for both birds and infrastructure. It has been demonstrated that anchor-type pylons, with strain insulators, are amongst the most dangerous of these structures. Our goal was to develop a methodological approach to evaluate the ways in which raptors perch on the six most commonly used strain insulator configurations in Spain, and to build a risk index that can be used to prioritise them. To study the ways raptors perch, we worked with six wildlife rescue centres in central Spain for almost a year assessing these six strain insulator configurations in 83 perch trials with 176 raptors in ample flying pens. We analysed 475 complete survey days, with an approximate number of 258,960 analysed pictures, including 6,766 perchings on strain insulators. We assessed the influential factors for these 6,766 perchings and developed a novel approach to prioritise strain insulator configurations that can be used anywhere. Our results suggest that longer insulator strains (i.e. PECA-1000 and Caon-C3670) are the safest, according to our prioritization criteria, although these results require further assessment in the field. Managers and conservationists should take into account these results to improve management and conservation actions.

scholarly journals Extracellular-Vesicle-Based Coatings Enhance Bioactivity of Titanium Implants—SurfEV

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1445
Author(s):  
Taisa Nogueira Pansani ◽  
Thanh Huyen Phan ◽  
Qingyu Lei ◽  
Alexey Kondyurin ◽  
Bill Kalionis ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Titanium Surface ◽  
Wound Closure ◽  
Cell Types ◽  
Extracellular Vesicle ◽  
Tissue Growth ◽  
Titanium Implants ◽  
The Body ◽  
High Concentrations ◽  
And Migration

Extracellular vesicles (EVs) are nanoparticles released by cells that contain a multitude of biomolecules, which act synergistically to signal multiple cell types. EVs are ideal candidates for promoting tissue growth and regeneration. The tissue regenerative potential of EVs raises the tantalizing possibility that immobilizing EVs on implant surfaces could potentially generate highly bioactive and cell-instructive surfaces that would enhance implant integration into the body. Such surfaces could address a critical limitation of current implants, which do not promote bone tissue formation or bond bone. Here, we developed bioactive titanium surface coatings (SurfEV) using two types of EVs: secreted by decidual mesenchymal stem cells (DEVs) and isolated from fermented papaya fluid (PEVs). For each EV type, we determined the size, morphology, and molecular composition. High concentrations of DEVs enhanced cell proliferation, wound closure, and migration distance of osteoblasts. In contrast, the cell proliferation and wound closure decreased with increasing concentration of PEVs. DEVs enhanced Ca/P deposition on the titanium surface, which suggests improvement in bone bonding ability of the implant (i.e., osteointegration). EVs also increased production of Ca and P by osteoblasts and promoted the deposition of mineral phase, which suggests EVs play key roles in cell mineralization. We also found that DEVs stimulated the secretion of secondary EVs observed by the presence of protruding structures on the cell membrane. We concluded that, by functionalizing implant surfaces with specialized EVs, we will be able to enhance implant osteointegration by improving hydroxyapatite formation directly at the surface and potentially circumvent aseptic loosening of implants.

scholarly journals Use of Dynamic Analysis to Investigate the Behaviour of Short Neutral Sections in the Overhead Line Electrification

2021 ◽  
Vol 6 (5) ◽  
pp. 62
Author(s):  
John Morris ◽  
Mark Robinson ◽  
Roberto Palacin
Keyword(s):  
Dynamic Analysis ◽  
Dynamic Simulation ◽  
Model Simulation ◽  
Analysis Tool ◽  
Overhead Line ◽  
Element Analysis ◽  
Novel Approach ◽  
Section Model ◽  
The Uk ◽  
Neutral Section

The ‘short’ neutral section is a feature of alternating current (AC) railway overhead line electrification that is often unreliable and a source of train delays. However hardly any dynamic analysis of its behaviour has been undertaken. This paper briefly describes the work undertaken investigating the possibility of modelling the behaviour using a novel approach. The potential for thus improving the performance of short neutral sections is evaluated, with particular reference to the UK situation. The analysis fundamentally used dynamic simulation of the pantograph and overhead contact line (OCL) interface, implemented using a proprietary finite element analysis tool. The neutral section model was constructed using physical characteristics and laboratory tests data, and was included in a validated pantograph/OCL simulation model. Simulation output of the neutral section behaviour has been validated satisfactorily against real line test data. Using this method the sensitivity of the neutral section performance in relation to particular parameters of its construction was examined. A limited number of parameter adjustments were studied, seeking potential improvements. One such improvement identified involved the additional inclusion of a lever arm at the trailing end of the neutral section. A novel application of pantograph/OCL dynamic simulation to modelling neutral section behaviour has been shown to be useful in assessing the modification of neutral section parameters.

Dealing with austerity and migration in the northern European cleaning sector: Social partner strategies to strengthen wage floors

2018 ◽  
Vol 24 (4) ◽  
pp. 373-389 ◽  
Author(s):  
Sissel Trygstad ◽  
Trine P Larsen ◽  
Kristine Nergaard
Keyword(s):  
Industrial Relations ◽  
Eu Enlargement ◽  
Social Partner ◽  
National Differences ◽  
The Social ◽  
Wage Regulation ◽  
And Migration ◽  
Industrial Cleaning ◽  
The Uk ◽  
Exerted Pressure

Industrial cleaning shares some common features across countries. Institutions for collective wage regulation are fragile, the market is highly price-sensitive and skewed competition has exerted pressure on wages and conditions. Increased cross-border mobility of labour and enterprises after EU enlargement brought new sources of competitive pressure, which was amplified by the subsequent economic crisis. We study changes in collective regulation in industrial cleaning in Denmark, Germany, Norway and the UK since the turn of the century, and find that the social partners have responded differently to the challenges. We discuss these responses in the light of national differences in industrial relations regimes and the regulatory tools available for the organized actors.

M2-Polarized Macrophages Mediate Wound Healing by Regulating Connective Tissue Growth Factor via AKT, ERK 1/2, and STAT 3 Signaling Pathways

2021 ◽  
Author(s):  
Si-Min Zhang ◽  
Chuan-Yuan Wei ◽  
Qiang Wang ◽  
Lu Wang ◽  
Lu Lu ◽  
...  
Keyword(s):  
Wound Healing ◽  
Tissue Growth ◽  
Cutaneous Wound Healing ◽  
M2 Macrophages ◽  
Cutaneous Wound ◽  
Stat3 Signaling ◽  
M2 Polarization ◽  
Stat3 Signaling Pathway ◽  
And Migration ◽  
Proliferation And Migration

Abstract Background: Timely and sufficient recruitment of M1 macrophages and M2 polarization are necessary for fibrous repair during cutaneous wound healing. The inherent mechanism of how M2 polarization mediate wound healing is worth exploring and illustrating. Abnormally up-regulated connective tissue growth factor (CTGF) is closely related with multiple organ fibrosis, including cardiac, pulmonary, hepatic, renal, and cutaneous fibrosis. Previous studies have reported that M2-polarized macrophages contribute to hepatic and renal fibrosis by secreting CTGF. It is worth discussing if M2 macrophages regulate fibrosis through secreting CTGF in cutaneous wound healing.Methods: We established the murine full-thickness excisional wound model and inhibited macrophages during proliferation phase (mainly M2 and M1-M2 polarization) with clodronate liposomes to analyze how M2 macrophages mediate wound healing rates, collagen deposition, collagen 1/3 expression, and Ki67 expression in vivo. Furthermore, M2 polarization was induced by IL-4 and in vitro. F4/80+CD206+ M2 macrophages were measured by flow cytometry. The morphological characteristics were observed. Secretion of IL-6, TNF-α, IL-10, TGF-β1, and CTGF was tested by ELISA. CTGF gene of M2 was blocked using siCTGF. Effects of M2 on proliferation and migration of fibroblasts were detected by CCK8 and cellular wound healing assay. Protein level of AKT, ERK1/2, and STAT3 pathway were assessed by western blotting.Results: Depletion of macrophages at proliferation phase (mainly M2 and M1-M2 polarization) resulted in delayed cutaneous wound closure and down-regulation of wound healing rates, collagen deposition, collagen 1/3 expression, and Ki67 expression. M2 polarization was induced, which producing more CTGF, TGF-β1, and IL-6, as well as less TNF-α and IL-10. Blockade of CTGF in M2 macrophages deactivated fibroblast proliferation and migration. Addition of recombinant CTGF restored the promotional effects of M2 macrophages on fibroblast proliferation and migration. Blockade of CTGF in M2 mediate fibroblasts via down-regulating AKT, ERK1/2, and STAT3 signaling pathway.Conclusion: Our research, for the first time, indicated that M2-polarized macrophages promoted cutaneous wound healing by secreting CTGF, which further mediating proliferation and migration of fibroblasts via AKT, ERK1/2, and STAT3 signaling pathway.

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