Large-Scale Patterns of Green Turtle Trophic Ecology in the Eastern Pacific Oceans

Trophic position and niche width are fundamental components of a species\u27 ecology, reflecting resource use, and influencing key demographic parameters such as somatic growth, maturation, and survival. Concepts about a species\u27 trophic niche space have important implications for local management and habitat protection, and can shed light about resilience to changing climate for species occurring over broad spatial scales. For elusive marine animals such as sea turtles, trophic niche is challenging to study, and researchers often rely on other metrics, such as isotopic niche, as a proxy. Here, stable isotope analysis (delta C-13 and delta N-15 values) was conducted on bulk skin tissue of 718 green turtles (Chelonia mydas) distributed among 16 foraging areas in the eastern Pacific from the USA to Chile, a range spanning similar to 10,000 km. Compound-specific nitrogen isotope analysis of amino acids (CSIA-AA) was applied to 21 turtles among seven sites. Isotopic niche space was determined via Bayesian ellipse area (BEA) and convex hull area (CHA) analyses of bulk isotope values, which were also used along with amino acid delta N-15 values to determine trophic position (TP). Substantial variability in bulk tissue delta C-13 and delta N-15 values was found within and among sites, and amino acid delta N-15 values confirmed this was largely due to spatial differences in baseline nitrogen isotopic compositions, but also to a lesser extent from TP differences among the green turtle foraging populations. Isotope niche space varied among sites, influenced by the diversity of prey types and relative input of terrestrial- vs. marine-derived nutrients; BEAs were the most suitable measurement of isotopic niche space due to the larger influence of outlying values with the CHA approach. Amino acid isotope-derived TP estimates that accounted for local habitat conditions (e.g., mixed seagrass/macroalgae diet) performed the best among several approaches; TP ranged from 2.3 to 3.6, which indicates an omnivorous diet for most populations. In addition to providing additional spatial resolution for delta C-13 and delta N-15 isoscapes in the eastern Pacific, especially in coastal habitats, this study further establishes CSIA-AA as an effective tool to study the trophic ecology of sea turtles across a variety of food webs and habitats

How do albino fish hear?

Pigmentation disorders such as albinism are occasionally associated with hearing impairments in mammals. Therefore, we wanted to investigate whether such a phenomenon also exists in non-mammalian vertebrates. We measured the hearing abilities of normally pigmented and albinotic specimens of two catfish species, the European wels Silurus glanis (Siluridae) and the South American bronze catfish Corydoras aeneus (Callichthyidae). The non-invasive auditory evoked potential (AEP) recording technique was utilized to determine hearing thresholds at 10 frequencies from 0.05 to 5 kHz. Neither auditory sensitivity nor shape of AEP waveforms differed between normally pigmented and albinotic specimens at any frequency tested in both species. Silurus glanis and C. aeneus showed the best hearing between 0.3 and 1 kHz; the lowest thresholds were 78.4 dB at 0.5 kHz in S. glanis (pigmented), 75 dB at 1 kHz in S. glanis (albinotic), 77.6 dB at 0.5 kHz in C. aeneus (pigmented) and 76.9 dB at 1 kHz in C. aeneus (albinotic). This study indicates no association between albinism and hearing ability. Perhaps because of the lack of melanin in the fish inner ear, hearing in fishes is less likely to be affected by albinism than in mammals

Biliary epithelium and liver B cells exposed to bacteria activate intrahepatic MAIT cells through MR1

Background & AimsMucosal-Associated Invariant T (MAIT) cells are innate-like T cells characterised by the invariant TCR-chain, Vα7.2-Jα33, and are restricted by MR1, which presents bacterial vitamin B metabolites. They are important for antibacterial immunity at mucosal sites; however, detailed characteristics of liver-infiltrating MAIT (LI-MAIT) and their role in biliary immune surveillance remain unexplored.MethodsThe phenotype and intrahepatic localisation of human LI-MAIT cells was examined in diseased and normal livers. MAIT cell activation in response to E. coli-exposed macrophages, biliary epithelial cells (BEC) and liver B cells was assessed with/without anti-MR1.ResultsIntrahepatic MAIT cells predominantly localised to bile ducts in the portal tracts. Consistent with this distribution, they expressed biliary tropic chemokine receptors CCR6, CXCR6, and integrin αEβ7. LI-MAIT cells were also present in the hepatic sinusoids and possessed tissue-homing chemokine receptor CXCR3 and integrins LFA-1 and VLA-4, suggesting their recruitment via hepatic sinusoids. LI-MAIT cells were enriched in the parenchyma of acute liver failure livers compared to chronic diseased livers. LI-MAIT cells had an activated, effector memory phenotype, expressed α4β7 and receptors for IL-12, IL-18, and IL-23. Importantly, in response to E. coli-exposed macrophages, liver B cells and BEC, MAIT cells upregulated IFN-γ and CD40 Ligand and degranulated in an MR1-dependent, cytokine-independent manner. In addition, diseased liver MAIT cells expressed T-bet and RORγt and the cytokines IFN-γ, TNF-α, and IL-17.ConclusionsOur findings provide the first evidence of an immune surveillance effector response for MAIT cells towards BEC in human liver; thus they could be manipulated for treatment of biliary disease in the future

The Strange Death of Tory Liverpool: Conservative Electoral Decline in Liverpool, 1945-1996

In modern discourse Liverpool is a by-word for anti-Tory sentiment, yet the city has not always been so inhospitable for the Conservatives. From the mid-18th century until the 1970s the Conservatives dominated the city council and often held over half of Liverpool’s parliamentary constituencies. Whilst popular opinion ascribes Conservative decline in Liverpool to Margaret Thatcher, Conservative Prime Minister from 1979 to 1990, it began a decade before Thatcher gained power. This article argues that Conservative decline in Liverpool was due to the increasing inability of socialisation to create new Conservative voters, coupled with dissatisfaction with the Heath government and a rejection of unresponsive local party machines. The Liberal Party, through their use of pavement politics, were able to exploit these issues. Their 1973 local election victory allowed them to displace the Conservatives as the main opposition to Labour in most of the city, thus beginning the strange death of Tory Liverpool. Liverpool, Conservative Party decline, working class Conservatism, socialisation, Liverpool Liberal Part

Exercise and Type 2 Diabetes: The American College of Sports Medicine and the American Diabetes Association: joint position statement

Although physical activity (PA) is a key element in the prevention and management of type 2 diabetes, many with this chronic disease do not become or remain regularly active. High-quality studies establishing the importance of exercise and fitness in diabetes were lacking until recently, but it is now well established that participation in regular PA improves blood glucose control and can prevent or delay type 2 diabetes, along with positively affecting lipids, blood pressure, cardiovascular events, mortality, and quality of life. Structured interventions combining PA and modest weight loss have been shown to lower type 2 diabetes risk by up to 58% in high-risk populations. Most benefits of PA on diabetes management are realized through acute and chronic improvements in insulin action, accomplished with both aerobic and resistance training. The benefits of physical training are discussed, along with recommendations for varying activities, PA-associated blood glucose management, diabetes prevention, gestational diabetes mellitus, and safe and effective practices for PA with diabetes-related complications

A Vector Level Control Function for Generalized Octree Mesh Generation

Due to the complexity of 3D geometry structure, regular gridding algorithms often generate a very large amount of mesh points which requires an enormous amount of computational power for later device and process simulations. A vector level control function and related generalized octree method is presented in this paper, and it allows mesh refinement in selected directions only. Thus the grid points can be placed more optimally and that enables efficient device and process simulations. 1. Introduction Some quadtree/octree based mesh generation schemes have been employed for finite element methods used in device [1] and process simulations [3] because of the simplicity of the tree data structure and its advantage in faciliating adaptive mesh refinement. The quadtree mesh generation scheme recursively partitions a square into four smaller, equal size squares; the octreetakes a cube and partitions it into eight smaller cubes. This set of squares or cubes form a tree. Usually a one-level ..

Understanding and Leveraging a Supplier's CMMI Efforts: A Guidebook for Acquirers

This guidebook is designed to help acquisition organizations benefit from their suppliers’ use of CMMI for Development, which is a collection of best practices that addresses product development and maintenance activities throughout the product lifecycle. This guidebook also helps acquisition organizations avoid problems that can result from unrealistic expectations. High capability and maturity level ratings alone do not guarantee program success. This guidebook helps clarify what those ratings can and cannot do for a development program. It describes how acquirers can • interpret suppliers’ claims of achieving a CMMI rating • request, understand, interpret, and use supplier appraisal results, and • apply methods that leverage a supplier’s process improvement initiatives