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Case study research provides nurses with a form of inquiry that is holistic and appropriate for a variety of populations. Jeanine Gangeness and Eleanor Yurkovich discuss components of case study research, including its theoretical base, design methods, multiple data sources and analysis. The information presented is expanded on by using a planned population-based, multiple-case explanatory study.
Cell adhesion is an integral part of many physiological processes in tissues, including development, tissue maintenance, angiogenesis, and wound healing. Recent advances in materials science (including microcontact printing, soft lithography, microfluidics, and nanotechnology) have led to strongly improved control of extracellular ligand distribution and of the properties of the micromechanical environment. As a result, the investigation of cellular response to the physical properties of adhesive surfaces has become a very active area of research. Sophisticated use of elastic substrates has revealed that cell organization in soft media is determined by active mechanosensing at cell-matrix adhesions. In order to determine the underlying mechanisms, quantification and biophysical modelling are essential. In tissue engineering, theory might help to design new environments for cells.
Rapid developments in the field of molecular biology and gene technology resulted in generation of many macromolecular drugs including peptides, proteins, polysaccharides and nucleic acids in great number possessing superior pharmacological efficacy with site specificity and devoid of untoward and toxic effects. However, the main impediment for the oral delivery of these drugs as potential therapeutic agents is their extensive presystemic metabolism, instability in acidic environment resulting into inadequate and erratic oral absorption. Parenteral route of administration is the only established route that overcomes all these drawbacks associated with these orally less/inefficient drugs. But, these formulations are costly, have least patient compliance, require repeated administration, in addition to the other hazardous effects associated with this route. Over the last few decades' pharmaceutical scientists throughout the world are trying to explore transdermal and transmucosal routes as an alternative to injections. Among the various transmucosal sites available, mucosa of the buccal cavity was found to be the most convenient and easily accessible site for the delivery of therapeutic agents for both local and systemic delivery as retentive dosage forms, because it has expanse of smooth muscle which is relatively immobile, abundant vascularization, rapid recovery time after exposure to stress and the near absence of langerhans cells. Direct access to the systemic circulation through the internal jugular vein bypasses drugs from the hepatic first pass metabolism leading to high bioavailability. Further, these dosage forms are self-administrable, cheap and have superior patient compliance. Developing a dosage form with the optimum pharmacokinetics is a promising area for continued research as it is enormously important and intellectually challenging. With the right dosage form design, local environment of the mucosa can be controlled and manipulated in order to optimize the rate of drug dissolution and permeation. A rational approach to dosage form design requires a complete understanding of the physicochemical and biopharmaceutical properties of the drug and excipients. Advances in experimental and computational methodologies will be helpful in shortening the processing time from formulation design to clinical use. This paper aims to review the developments in the buccal adhesive drug delivery systems to provide basic principles to the young scientists, which will be useful to circumvent the difficulties associated with the formulation design.
Almost 50 million Americans--about one in five--live with a mental or physical disability, many in homes that are inconvenient, restrictive, or dangerous for them. Modifying the home using universal (barrier-free) design, architectural accessibility, and other such concepts can reduce the risk of falls and improve overall function. Nurses can be involved by assessing patients' living quarters and recommending specific modifications.
Many reserve selection tools have been created to solve the minimum representation problem, selecting the least costly set of sites such that all conservation surrogate targets are met. However, there are practical problems and risks associated with this method for finding reserve network alternatives, including the treatment of persistence-promoting design considerations as secondary objectives. Here, reserve networks are generated for a hypothetical landscape where the objectives are to maximize representation and to maximize conformance with persistence-promoting design principles, subject to a constraint on the number of sites in the networks. The efficiency of potential networks is calculated as the total number of species captured in the included sites. Effectiveness is measured as a function of the size of individual patches, total reserve size, and extent of interpatch connectivity. A series of tradeoff curves are produced showing the nondominated compromise alternatives between representation and design for organisms with varying dispersal capabilities. Each alternative comprises a list of selected sites and covers species, as well as the identities and locations of the interpatch edges connecting the sites. Potential ways to use the results are discussed.
BACKGROUND: Well-designed public open space (POS) that encourages physical activity is a community asset that could potentially contribute to the health of local residents. METHODS: In 1995-1996, two studies were conducted-an environmental audit of POS over 2 acres (n =516) within a 408-km2 area of metropolitan Perth, Western Australia; and personal interviews with 1803 adults (aged 18 to 59 years) (52.9% response rate). The association between access to POS and physical activity was examined using three accessibility models that progressively adjusted for distance to POS, and its attractiveness and size. In 2002, an observational study examined the influence of attractiveness on the use of POS by observing users of three pairs of high- and low-quality (based on attractiveness) POS matched for size and location. RESULTS: Overall, 28.8% of respondents reported using POS for physical activity. The likelihood of using POS increased with increasing levels of access, but the effect was greater in the model that adjusted for distance, attractiveness, and size. After adjustment, those with very good access to large, attractive POS were 50% more likely to achieve high levels of walking (odds ratio, 1.50; 95% confidence level, 1.06-2.13). The observational study showed that after matching POS for size and location, 70% of POS users observed visited attractive POS. CONCLUSIONS: Access to attractive, large POS is associated with higher levels of walking. To increase walking, thoughtful design (and redesign) of POS is required that creates large, attractive POS with facilities that encourage active use by multiple users (e.g., walkers, sports participants, picnickers).
Multi-agent Systems (MAS) offer a conceptual approach to include multi-actor decision making into models of land use change. The main goal is to explore the use of MAS to simulate spatial scenarios based on modelling multi-actor decision-making within a spatial planning process. We demonstrate MAS that consists of agents representing organizations and interest groups involved in an urban allocation problem during a land use planning process. The multi-actor based decision-making is modelled by generating beliefs and preferences of actors about the location of and relation between spatial objects. This allows each agent to confront these beliefs and preferences with it's own desires and with that of other agents. The MAS loosely resembles belief, desire and intentions architecture. Based on a case study for a hypothetical land use planning situation in a study area in the Netherlands we discuss the potential and limitations of the MAS to build models that enable spatial planners to include the 'actor factor' in their analysis and design of spatial scenarios. In addition, our experiments revealed the need for further research on the representation of spatial objects and reasoning, learning and communication about allocation problems using MAS.
The National Park Service (NPS) is increasingly focusing on alternative transportation systems in national parks to address environmental and social problems arising from a historical reliance on personal automobiles as the primary means of visitor access. Despite the potential advantages, alternative transportation may require a reorientation in the way that Americans have experienced national parks since the advent of auto-tourism in the early twentieth century. Little research exists, however, on visitor perspectives towards alternative transportation or the rationale underlying their perspectives. It remains unclear how transportation systems affect visitors' experiences of the park landscape or the factors influencing their travel behavior in the parks. This report presents an interpretive study of visitor perspectives toward transportation management in the Yosemite Valley area of Yosemite National Park, California. Qualitative analysis of 160 semi-structured interviews identified individual psychological factors as well as situational influences that affect visitors' behavior and perspectives. Individual psychological factors include perceived freedom, environmental values and beliefs, prior experience with Yosemite National Park and other national parks, prior experience with alternative transportation in national parks, and sensitivity to subjective perceptions of crowding. Situational factors included convenience, access, and flexibility of travel modes, as well as type of visit, type of group, and park use level. Interpretive communication designed to encourage voluntary visitor use of alternative transportation should focus on these psychological and situational factors. Although challenges remain, the results of this study suggest approaches for shaping the way Americans visit and experience their national parks to encourage environmental sustainability.
Ecological damage and loss of natural habitats have been resulting in the fragmentation of wild animal and plant population, and nature reserves have become the islands of habitats. The traditional approach that focuses on a single and isolated nature reserve is not enough to protect biodiversity. Ecological processes and components of biodiversity in broad temporal and spatial scope should be protected, and a whole conservation network should be established. Based on the requirements and the trends of biodiversity conservation at home and abroad, this paper presented the concept of ecological security design for nature reserves, which is a coordinated planning strategy that integrates ecological, social and economic aspects. Firstly, a network of nature reserves is designed at regional level; secondly, the area, shape, internal zoning of a nature reserve is designed at the node (nature reserve) of the network; and finally, the connectivity between the network and nodes (corridors) is designed. Network design of nature reserves should maintain the regional integrity and the ecological process integrity of ecosystems. Iterative method, integer linear programming, and Geographic Approach (GAP) should be employed to provide blueprints of conservation planning for one or multiple conservation objectives.
This paper revisits the question of the relationship between rural road geometric characteristics, accident rates and their prediction, using a rigorous non-parametric statistical methodology known as hierarchical tree-based regression. The goal of this paper is twofold: first, it develops a methodology that quantitatively assesses the effects of various highway geometric characteristics on accident rates and, second, it provides a straightforward, yet fundamentally and mathematically sound way of predicting accident rates on rural roads. The results show that although the importance of isolated variables differs between two-lane and multilane roads, 'geometric design' variables and pavement condition' variables are the two most important factors affecting accident rates. Further, the methodology used in this paper allows for the explicit prediction of accident rates for given highway sections, as soon as the profile of a road section is given.
This paper is directed to the further understanding of the problems of fatigue and workload and their role in diminishing driving capability. We present a specific strategy designed to defend against the adverse effects of fatigue and workload extremes through the use of adaptive driver systems. To begin, the work presents a brief critique of Muscio's constraints on developing a test of fatigue. In criticizing these constraints, we point to the commonalities between all energetic reflections of human performance and use advances in stress theory to explain the problems of and resolution to the question of fatigue. We link fatigue and chronic workload and use this coadunation as a basis for the operation of adaptive driver systems which are specifically designed to combat driving impairment. A specific program is then explained in detail and illustrations are given as to how an extension of previous efforts can address the problem of the drowsy and chronically fatigued driver. Future recommendations are articulated.
A theoretical model is proposed in which road safety in a single country depends upon parochial considerations, such as police enforcement, and upon global considerations, such as international road safety technology. We show that there is a non-spurious relationship between the downward trend in the rate of road accidents in Israel and the road accident rate abroad. We suggest that this reflects the international propagation of road safety technology as it is embodied in motor vehicles and road design, rather than parochial road safety policy. Recent developments in the econometric analysis of time series are used to estimate the model using data for Israel. We make no direct attempt to explain the downward trend in the rate of road accidents outside Israel.
This is Part III of a three-part series that examines various aspects of ergonomic deficiencies at work. Part I examined pain at work and the association between such pain or discomfort and a poorly designed workplace or poorly structured job. Part II considered causes of ergonomic deficiencies and their identification and assessment through the use of checklists. Part III demonstrates that treating the symptoms or apparent proximate causes does not assure correction of the root causes, and suggests strategies for correcting ergonomic deficiencies.
Indoor nonindustrial work environments were designated a priority research area through the nationwide stakeholder process that created the National Occupational Research Agenda. A multidisciplinary research team used member consensus and quantitative estimates, with extensive external review, to develop a specific research agenda. The team outlined the following priority research topics: building-influenced communicable respiratory infections, building-related asthma/allergic diseases, and nonspecific building-related symptoms; indoor environmental science; and methods for increasing implementation of healthful building practices. Available data suggest that improving building environments may result in health benefits for more than 15 million of the 89 million US indoor workers, with estimated economic benefits of $5 to $75 billion annually. Research on these topics, requiring new collaborations and resources, offers enormous potential health and economic returns.
This is Part II of a three-part series that examines various aspects of ergonomic deficiencies at work. Part I examined pain at work and the association between such pain or discomfort and a poorly designed workplace or poorly structured job. Part II considers causes of ergonomic deficiencies and their identification and assessment through the use of checklists. Part III demonstrates that treating the symptoms or apparent proximate causes does not assure correction of the root causes, and suggests strategies for correcting ergonomic deficiencies.
OBJECTIVES: To investigate environmental barriers reported by people with spinal cord injury (SCI), and to determine the relative impact of environmental barriers compared with demographic and injury characteristics and activity limitations in predicting variation in participation and life satisfaction. DESIGN: Cross-sectional, follow-up survey. SETTING: Individuals rehabilitated at 16 federally designated Model Spinal Cord Injury Systems of care, now living in the community. PARTICIPANTS: People with SCI (N=2726) who completed routine follow-up research interviews between 2000 and 2002. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The Craig Hospital Inventory of Environmental Factors-Short Form (CHIEF-SF), the Craig Handicap Assessment and Reporting Technique-Short Form, and the Satisfaction With Life Scale. RESULTS: The top 5 environmental barriers reported by subjects with SCI, in descending order of importance, were the natural environment, transportation, need for help in the home, availability of health care, and governmental policies. The CHIEF-SF subscales accounted for only 4% or less of the variation in participation; they accounted for 10% of the variation in life satisfaction. CONCLUSIONS: The inclusion of environmental factors in models of disability was supported, but were found to be more strongly related to life satisfaction than to societal participation.
New and emerging media technologies have the potential to induce a variety of experiences in users. In this paper, it is argued that the inducement of experience presupposes that users are absorbed in the illusion created by these media. Looking to another successful visual medium, film, this paper borrows from the techniques used in "shaping experience" to hold spectators' attention in the illusion of film, and identifies what breaks the illusion/experience for spectators. This paper focuses on one medium, virtual reality (VR), and advocates a transparent or "invisible style" of interaction. We argue that transparency keeps users in the "flow" of their activities and consequently enhances experience in users. Breakdown in activities breaks the experience and subsequently provides opportunities to identify and analyze potential causes of usability problems. Adopting activity theory, we devise a model of interaction with VR--through consciousness and activity--and introduce the concept of breakdown in illusion. From this, a model of effective interaction with VR is devised and the occurrence of breakdown in interaction and illusion is identified along a continuum of engagement. Evaluation guidelines for the design of experience are proposed and applied to usability problems detected in an empirical study of a head-mounted display (HMD) VR system. This study shows that the guidelines are effective in the evaluation of VR. Finally, we look at the potential experiences that may be induced in users and propose a way to evaluate user experience in virtual environments (VEs) and other new and emerging media.
Field investigation conducted on Boulder Creek in Boulder, Colorado evaluated impacts of flood control maintenance activities on flood conveyance, water quality, and fish habitat. Thirty-nine transects were monitored at one control site and two maintenance sites over a period of eight months. Each site was visited on more than 50 occasions in order to characterize pre- and post-maintenance conditions, and to monitor maintenance activities. Measurements along the transects included substrate composition, flow depth, velocity, and elevation. Reach-average values were assigned to variables such as in-stream vegetation, streambank stability, and woody vegetation before and after maintenance. Water temperature, dissolved oxygen, pH, specific conductance, and turbidity were sampled, and habitat suitability indices were developed pre- and post-maintenance for seven indicator fish species. Water quality impacts during maintenance consisted of high turbidity levels (> 400 NTU), which retumed to background levels (0.1-15 NTU) overnight, as well as changes in mean temperature and pH. Alteration of physical channel characteristics as a result of maintenance had limited effects on habitat quality for four of seven fish species, but caused improvements in habitat quality for three fish species. The main implications of this study for floodplain management are that: (1) Flood control maintenance practices can be in direct conflict with water quality and fish habitat objectives, and should be carefully designed and implemented by an interdisciplinary team. (2) Physical habitat for some fish species can be improved as well as reduced by maintenance activities. Habitat suitability curves may be useful tools for evaluating limiting factors of the habitat and for identifying opportunities for habitat improvements as part of maintenance.