402 research outputs found

    Corrigendum: hypoxic induced decrease in oxygen consumption in cuttlefish (Sepia officinalis) Is Associated with minor increases in Mantle Octopine but no changes in markers of protein turnover

    Get PDF
    Corrige o artigo http://hdl.handle.net/10400.1/10858 [This corrects the article DOI: 10.3389/fphys.2017.00344.].info:eu-repo/semantics/publishedVersio

    Estimates of metabolic rate and major constituents of metabolic demand in fishes under field conditions: Methods, proxies, and new perspectives

    Get PDF
    Metabolic costs are central to individual energy budgets, making estimates of metabolic rate vital to understanding how an organism interacts with its environment as well as the role of species in their ecosystem. Despite the ecological and commercial importance of fishes, there are currently no widely adopted means of measuring field metabolic rate in fishes. The lack of recognized methods is in part due to the logistical difficulties of measuring metabolic rates in free swimming fishes. However, further development and refinement of techniques applicable for field-based studies on free swimming animals would greatly enhance the capacity to study fish under environmentally relevant conditions. In an effort to foster discussion in this area, from field ecologists to biochemists alike, we review aspects of energy metabolism and give details on approaches that have been used to estimate energetic parameters in fishes. In some cases, the techniques have been applied to field conditions; while in others, the methods have been primarily used on laboratory held fishes but should be applicable, with validation, to fishes in their natural environment. Limitations, experimental considerations and caveats of these measurements and the study of metabolism in wild fishes in general are also discussed. Potential novel approaches to FMR estimates are also presented for consideration. The innovation of methods for measuring field metabolic rate in free-ranging wild fish would revolutionize the study of physiological ecology

    White gold alloys:

    Full text link

    The power of modularity today: 20 years of “Design Rules”

    Get PDF
    In 2000, Carliss Baldwin and Kim Clark published “Design Rules: The Power of Modularity,” a book that introduced new ways of understanding and explaining the architecture of complex systems This Special Issue of Industrial and Corporate Change celebrates this seminal work, the research it has inspired, and the insights that these collective efforts have generated. In this introductory essay, we review the impact of “Design Rules” across numerous fields, including organization theory, competitive strategy, industry structure, and innovation management. We offer perspectives on key themes that emerge from contributions in this issue, including the alignment between organizational and technical designs (“mirroring”), the dynamics of industry evolution, and the role that individuals play in shaping and responding to system designs. We close by highlighting opportunities to apply the theory in Design Rules to new phenomena and puzzles that have emerged in the past 20 years

    Conceptual Analysis of Electron Transpiration Cooling for the Leading Edges of Hypersonic Vehicles

    Full text link
    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140441/1/6.2014-2674.pd

    The great ephemeral tattooed skin

    Get PDF
    The skin is always and already a series of planes which signify race, gender, age and such. Tattooing creates a new surface of potential significance upon the body. Tattooing can call into question concepts of volition in reference to the power to inscribe and define one’s subjectivity through one’s own skin, and the social defining of the subject. Skin is the involution or event between subject and object, will and cultural inscription, the social and the self. Feminism, particularly corporeal feminists, have attempted to think ways in which the female flesh may be recognized and self-defined without risking essentialism through reification of the meaning of ‘woman’s body’. Thinking the tattooed female body thus resonates with some of the risks and benefits feminism has found in theorizing a marginalized body. Using Deleuze, Guattari, Lyotard and other major influences on corporeal feminists this article explores ways in which significance is sought in skin and possible configurations of skin and world which challenge the desire to read the flesh as a legible incarnation of subjectivity

    Metabolic rate and rates of protein turnover in food-deprived cuttlefish, Sepia officinalis (Linnaeus 1758)

    Get PDF
    To determine the metabolic response to food deprivation, cuttlefish (Sepia officinalis) juveniles were either fed, fasted (3 to 5 days food deprivation), or starved (12 days food deprivation). Fasting resulted in a decrease in triglyceride levels in the digestive gland, and after 12 days, these lipid reserves were essentially depleted. Oxygen consumption was decreased to 53% and NH4 excretion to 36% of the fed group following 3-5 days of food deprivation. Oxygen consumption remained low in the starved group, but NH4 excretion returned to the level recorded for fed animals during starvation. The fractional rate of protein synthesis of fasting animals decreased to 25% in both mantle and gill compared with fed animals and remained low in the mantle with the onset of starvation. In gill, however, protein synthesis rate increased to a level that was 45% of the fed group during starvation. In mantle, starvation led to an increase in cathepsin A-, B-, H-, and L-like enzyme activity and a 2.3-fold increase in polyubiquitin mRNA that suggested an increase in ubiquitin-proteasome activity. In gill, there was a transient increase in the polyubiquitin transcript levels in the transition from fed through fasted to the starved state and cathepsin A-, B-, H-, and L-like activity was lower in starved compared with fed animals. The response in gill appears more complex, as they better maintain rates of protein synthesis and show no evidence of enhanced protein breakdown through recognized catabolic processes

    First order hyperbolic formalism for Numerical Relativity

    Get PDF
    The causal structure of Einstein's evolution equations is considered. We show that in general they can be written as a first order system of balance laws for any choice of slicing or shift. We also show how certain terms in the evolution equations, that can lead to numerical inaccuracies, can be eliminated by using the Hamiltonian constraint. Furthermore, we show that the entire system is hyperbolic when the time coordinate is chosen in an invariant algebraic way, and for any fixed choice of the shift. This is achieved by using the momentum constraints in such as way that no additional space or time derivatives of the equations need to be computed. The slicings that allow hyperbolicity in this formulation belong to a large class, including harmonic, maximal, and many others that have been commonly used in numerical relativity. We provide details of some of the advanced numerical methods that this formulation of the equations allows, and we also discuss certain advantages that a hyperbolic formulation provides when treating boundary conditions.Comment: To appear in Phys. Rev.

    Changing situational contexts present a constant challenge to software developers.

    Get PDF
    A software process can take many forms and its optimality demands that it should be harmonised with the needs of the given software development situational context. This theoretical proposition is reasonably clear. However, the finer details of the interaction between the software process and the factors of the situational context are much less obvious. In previously published research, the authors have elaborated a reference framework that identifies the factors of a situational context that affect the software process [1]. In this paper, we report on the application of our reference framework in an examination of the changing nature of software development situational contexts. Our corresponding study of fifteen software development companies indicates that certain factors appear more subject to change than others. This finding is a potentially important insight that can help us with the recurring challenge of adapting the software process to changing circumstances
    • 

    corecore