34,953 research outputs found

    Risk homeostasis in information security:challenges in confirming existence and verifying impact

    Get PDF
    The central premise behind risk homeostasis theory is that humans adapt their behaviors, based on external factors, to align with a personal risk tolerance level. In essence, this means that the safer or more secure they feel, the more likely it is that they will behave in a risky manner. If this effect exists, it serves to restrict the ability of risk mitigation techniques to effect improvements.The concept is hotly debated in the safety area. Some authors agree that the effect exists, but also point out that it is poorly understood and unreliably predicted. Other re-searchers consider the entire concept fallacious. It is important to gain clarity about whether the effect exists, and to gauge its impact if such evidence can indeed be found.In this paper we consider risk homeostasis in the context of information security. Similar to the safety area, information security could well be impaired if a risk homeostasis effect neutralizes the potential benefits of risk mitigation measures. If the risk homeostasis effect does indeed exist and does impact risk-related behaviors, people will simply elevate risky behaviors in response to feeling less vulnerable due to following security procedures and using protective technologies.Here we discuss, in particular, the challenges we face in confirming the existence and impact of the risk homeostasis effect in information security, especially in an era of ethical research practice

    A review of the ecological effectiveness of subtidal marine reserves in Central California, Part I: Synopsis of scientific investigations

    Get PDF
    Marine reserves, often referred to as no-take MPAs, are defined as areas within which human activities that can result in the removal or alteration of biotic and abiotic components of an ecosystem are prohibited or greatly restricted (NRC 2001). Activities typically curtailed within a marine reserve are extraction of organisms (e.g., commercial and recreational fishing, kelp harvesting, commercial collecting), mariculture, and those activities that can alter oceanographic or geologic attributes of the habitat (e.g., mining, shore-based industrial-related intake and discharges of seawater and effluent). Usually, marine reserves are established to conserve biodiversity or enhance nearby fishery resources. Thus, goals and objectives of marine reserves can be inferred, even if they are not specifically articulated at the time of reserve formation. In this report, we review information about the effectiveness of the three marine reserves in the Monterey Bay National Marine Sanctuary (Hopkins Marine Life Refuge, Point Lobos Ecological Reserve, Big Creek Ecological Reserve), and the one in the Channel Islands National Marine Sanctuary (the natural area on the north side of East Anacapa Island). Our efforts to objectively evaluate reserves in Central California relative to reserve theory were greatly hampered for four primary reasons; (1) few of the existing marine reserves were created with clearly articulated goals or objectives, (2) relatively few studies of the ecological consequences of existing reserves have been conducted, (3) no studies to date encompass the spatial and temporal scope needed to identify ecosystem-wide effects of reserve protection, and (4) there are almost no studies that describe the social and economic consequences of existing reserves. To overcome these obstacles, we used several methods to evaluate the effectiveness of subtidal marine reserves in Central California. We first conducted a literature review to find out what research has been conducted in all marine reserves in Central California (Appendix 1). We then reviewed the scientific literature that relates to marine reserve theory to help define criteria to use as benchmarks for evaluation. A recent National Research Council (2001) report summarized expected reserve benefits and provided the criteria we used for evaluation of effectiveness. The next step was to identify the research projects in this region that collected information in a way that enabled us to evaluate reserve theory relative to marine reserves in Central California. Chapters 1-4 in this report provide summaries of those research projects. Contained within these chapters are evaluations of reserve effectiveness for meeting specific objectives. As few studies exist that pertain to reserve theory in Central California, we reviewed studies of marine reserves in other temperate and tropical ecosystems to determine if there were lessons to be learned from other parts of the world (Chapter 5). We also included a discussion of social and economic considerations germane to the public policy decision-making processes associated with marine reserves (Chapter 6). After reviewing all of these resources, we provided a summary of the ecological benefits that could be expected from existing reserves in Central California. The summary is presented in Part II of this report. (PDF contains 133 pages.

    Line-Strength Indices in Bright Spheroidals: Evidence for a Stellar Population Dichotomy between Spheroidal and Elliptical Galaxies

    Get PDF
    We present new measurements of central line-strength indices (namely Mg2, , and Hbeta and gradients for a sample of 6 bright spheroidal galaxies (Sph's) in the Virgo cluster. Comparison with similar measurements for elliptical galaxies (E's), galactic globular clusters (GGC's), and stellar population models yield the following results: (1) In contrast with bright E's, bright Sph's are consistent with solar abundance [Mg/Fe] ratios; (2) Bright Sph's exhibit metallicities ranging from values typical for metal-rich GGC's to those for E's; (3) Although absolute mean ages are quite model dependent, we find evidence that the stellar populations of some (if not all) Sph's look significantly younger than GGC's; and (4) Mg2 gradients of bright Sph's are significantly shallower than those of E galaxies. We conclude that the dichotomy found in the structural properties of Sph and E galaxies is also observed in their stellar populations. A tentative interpretation in terms of differences in star formation histories is suggested.Comment: 14 pages, LaTeX file + 2 PostScript figures, aasms4.sty require

    Origins of the Human Genome Project

    Get PDF
    Dr. Cook-Deegan recounts some of the scientific and political history leading to controversy about the proper mix of private and public roles in pursuing genome research and bringing its fruits to bear, e.g., in preventing and curing disease

    Double Charged Higgs Bosons Production in eee^-e^---Collisions

    Get PDF
    In the framework of the models with Higgs triplets, double charged Higgs bosons production in the processes eeδL,Rγe^-e^-\to\delta ^{--}_{L,R}\gamma are considered.Comment: 7 pages, 2 figure

    Molecular genetics and conservation in the Galápagos

    Get PDF

    Star Clusters

    Full text link
    This review concentrates almost entirely on globular star clusters. It emphasises the increasing realisation that few of the traditional problems of star cluster astronomy can be studied in isolation: the influence of the Galaxy affects dynamical evolution deep in the core, and the spectrum of stellar masses; in turn the evolution of the core determines the highest stellar densities, and the rate of encounters. In this way external tidal effects indirectly influence the formation and evolution of blue stragglers, binary pulsars, X-ray sources, etc. More controversially, the stellar density appears to influence the relative distribution of normal stars. In the opposite sense, the evolution of individual stars governs much of the early dynamics of a globular cluster, and the existence of large numbers of primordial binary stars has changed important details of our picture of the dynamical evolution. New computational tools which will become available in the next few years will help dynamical theorists to address these questions.Comment: 10 pages, 3 figures, Te

    Like-Sign Charged Higgs Boson Production in eee^-e^- Collisions at the NLC

    Full text link
    We consider the production of a pair of like-sign charged Higgs bosons in eee^-e^- collisions at the NLC within the context of several electroweak models with extended symmetry breaking sectors. We find that the rate for this process, which proceeds through WWW^-W^- fusion, is a very sensitive probe of the nature of these extended Higgs sectors and that the corresponding cross sections can vary by as much as several orders of magnitude at NLC energies. (Talk presented at the Santa Cruz Workshop on eee^-e^- Physics at the NLC, University of California, Santa Cruz, September 4-5, 1995.)Comment: 8 pages, uuencoded compressed postscript file. To obtain a copy of this paper send e-mail to [email protected]

    The potential impact on Florida-based marina and boating industries of a post-embargo Cuba: an analysis of geographic, physical, policy and industry trends

    Get PDF
    The information in this Technical Paper addresses the future of the US-Cuban marina and recreational boating industries from the geographic, physical, policy making and economic perspectives for a post-embargo Cuba. Each individual paper builds on the presentations made at the workshop, the information obtained in the subsequent trip to Cuba and presents in detailed form information which we hope is useful to all readers. (147pp.
    corecore