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PubMed1998

Breaking the cycle of violence among youth living in metropolitan Atlanta: a case history of kids alive and loved.

More teenagers in the United States die from gunshot wounds than from all natural causes of disease combined. Firearm-related mortality accounts for almost half of all deaths among African American teens. Residents of central cities have the highest probability of experiencing violent crimes. This article describes an innovative community-based intervention designed to break the cycle of violence among youth in metropolitan Atlanta. The intervention, Kids Alive and Loved (KAL), emerged from the African American community as one mother's response to the violent death of her 17-year-old son. The authors describe how her response to tragedy gave birth to a culturally appropriate intervention for youth exposed to violence. This article delineates the evolution of KAL, the role of community partners in the design of the intervention, and how diffusion of innovation theory has implications for understanding the KAL approach to breaking the cycle of violence.

Adolescent↗

PubMed2002

Identifying barriers to the use of research faced by public health physicians in Norway and developing an intervention to reduce them.

OBJECTIVES: To explore why public health physicians seldom use research-based information and to develop an intervention to remedy this on the basis of this study, other research literature and suitable theories of information-seeking and professional behaviour change. METHODS: A qualitative study was conducted using focus groups, observation of individuals and interviews. The setting was Norwegian public health practice; 52 public health physicians from all over Norway participated in the study. RESULTS: We identified several barriers to the use of scientific literature that could be categorised as: psychological variables; environmental variables; and source characteristics. We developed an intervention that attempts to address these barriers, informed by previous research on the effectiveness of interventions to change professional practice and incorporating elements from social cognitive theories and the theory of innovation diffusion. CONCLUSIONS: The Norweigian public health physician works in an isolated environment which does not facilitate searching or obtaining scientific information, which does not ask for this information and far less encourages its use as a basis for decision-making. An intervention tailored to reduce some of the barriers to research use may lead to more frequent and extensive use of such information in public health decision-making.

Anecdotes as Topic↗

PubMed2002

The diffusion of innovation: factors influencing the uptake of telehealth.

The actual use of telehealth, particularly for clinical consultations, has in many cases been less than anticipated. The literature identifies a number of factors or barriers. These include legal issues, technical difficulties, time and convenience, cost and training/familiarity with the equipment. No single factor has been identified as being consistently present. Rogers' diffusion of innovation theory suggests that organizational structures and cultures will affect health professionals' perceptions of telehealth. The introduction of telehealth services affects existing work practices and workflows. We believe that it is necessary to develop strategies for the introduction of telehealth applications which take into account the idiosyncrasies of the health service sector, and the particular structures and cultures of individual organizations within that sector.

Journal Article↗

PubMed2004

The Mozart effect: tracking the evolution of a scientific legend.

Theories of the diffusion of ideas in social psychology converge on the assumption that shared beliefs (e.g., social representations, rumours and legends) propagate because they address the needs or concerns of social groups. But little empirical research exists demonstrating this link. We report three media studies of the diffusion of a scientific legend as a particular kind of shared belief. We studied the Mozart effect (ME), the idea that listening to classical music enhances intelligence. Study 1 showed that the ME elicited more persistent media attention than other science reports and this attention increased when the ME was manifested in events outside of science. Study 2 suggested that diffusion of the ME may have responded to varying levels of collective anxiety. Study 3 demonstrated how the content of the ME evolved during diffusion. The results provide evidence for the functionality of diffusion of ideas and initial elements for a model of the emergence and evolution of scientific legends.

Adolescent↗

PubMed2005

Dynamic evolution of the spectrum of long-period fiber Bragg gratings fabricated from hydrogen-loaded optical fiber by ultraviolet laser irradiation.

Long-period fiber Bragg gratings fabricated by exposure of hydrogen-loaded fiber to UV laser light exhibit large-scale dynamic evolution for approximately two weeks at room temperature. During this time two distinct features show up in their spectrum: a large upswing in wavelength and a substantial deepening of the transmission minimum. The dynamic evolution of the transmission spectrum is explained quantitatively by use of Malo's theory of UV-induced quenching [Electron. Lett. 30, 442 (1994)] followed by refilling of hydrogen in the fiber core and the theory of hydrogen diffusion in the fiber material. The amount of hydrogen quenched by the UV irradiation is 6% of the loaded hydrogen.

Journal Article↗

PubMed1997

Does the photon-diffusion coefficient depend on absorption?

We investigate the controversy over the precise form of the photon diffusion coefficient and suggest that it is largely independent of absorption, i.e., Do = v/3mu(s)'. After presentation of the general theoretical arguments underlying this assertion, Monte Carlo simulations are performed and explicitly reveal that the absorption independent diffusion coefficient gives better agreement with theory than the traditionally accepted photon diffusion coefficient, D(mu)a = v/3(mu(s) + mu(a)). The importance of resolving this controversy for the proper characterization of the material optical properties is discussed.

Absorption↗

PubMedDate not supplied

Going to scale: re-engineering systems for primary care treatment of depression.

BACKGROUND: Recent trials have shown improved depression outcomes with chronic care models. We report the methods of a project that assesses the sustainability and transportability of a chronic care model for depression and change strategy. METHODS: In a randomized controlled trial (RCT), a clinical model for depression was implemented through a strategy supporting practice change. The clinical model is evidence based. The change strategy relies on established quality improvement programs and is informed by diffusion of innovations theory. Evaluation will address patient outcomes, as well as process of care and process of change. RESULTS: Five medical groups and health plans are participating in the trial. The RCT involves 180 clinicians in 60 practices. All practices assigned to the clinical model have implemented it. Participating organizations have the potential to disseminate this clinical model of care to 700 practices and 1,700 clinicians. CONCLUSIONS: It is feasible to implement the clinical model and change strategy in diverse practices. Follow-up evaluation will determine the impact, sustainability, and potential for dissemination. Materials are available through http://www. depression-primarycare.org; more in-depth descriptions of the clinical model and change strategy are available in the online-only appendixes to this article.

Cooperative Behavior↗

PubMed2000

Pattern of smoking initiation in Catalonia, Spain, from 1948 to 1992.

OBJECTIVES: This study analyzed the pattern of smoking initiation by sex and educational level in Catalonia, Spain. METHODS: Data from the 1994 Catalan Health Interview Survey were used (n = 12,245). The age and smoking status of each subject were reconstructed for each calendar period. Age-specific smoking initiation rates were calculated. RESULTS: Smoking initiation among females was rare until the 1960s, but from the period 1968-1972 onward a converging pattern was observed between the genders. Women with higher levels of education started smoking before other women, but the gradient of educational level has changed in recent years, with higher initiation rates among less-educated women. CONCLUSIONS: These results are consistent with diffusion-of-innovations theory and could be related to social and economic changes from the 1960s onward in Spain.

Adolescent↗

PubMed2000

Students together against negative decisions (STAND): evaluation of a school-based sexual risk reduction intervention in the rural south.

Twenty-one 10th graders selected as opinion leaders by their peers in a rural county in a southern state participated in a 36-hour peer-educator training program Students Together Against Negative Decisions (STAND) based on diffusion of innovations theory and the transtheoretical model. Comparison subjects received either a 22-hour leadership training course (n = 20) or no intervention (n = 45). STAND and comparison subjects completed a 154-item written knowledge, attitude, and behavior survey at the beginning of the training (Time 1), at the end of the training (Time 2), and again 8 months later (Time 3). One hundred and sixty-seven other 9th and 10th graders in the intervention county and 74 in the comparison county completed an abbreviated telephone interview at Time 1 and Time 3. At Time 3 STAND-trained peer educators reported significantly greater increases in AIDS Risk Behavior Knowledge (more than 4 times comparison groups), frequency of conversations with peers about birth control/condoms (+180% vs. +12%) and sexually transmitted diseases (STDs; +282% vs. -33%), condom use self efficacy (+16% vs. -1%), and consistent condom use (+28% vs. +15%). STAND teens also reported substantial favorable trends at Time 3, including increased condom use (+213% vs. +31%) and decreased unprotected intercourse (-30% vs. +29%). At Time 3 teens in the intervention county reported significantly greater increases in the number of people who talked with friends in the preceding 3 months about STDs (+39% vs. -19%) or with a parent/adult about sex (+6% vs. -37%). Intervention county teens also reported a substantial but nonsignificant 2.6-fold greater increase in condom use at last intercourse (+64% vs. +25%) but unfavorable changes in other risk behaviors. The STAND peer-educator training program appears to be an effective method for improving selected sexual knowledge, attitudes, and behaviors among participant teenagers in the rural South.

Adolescent↗

PubMed1975

Bronchial deposition of free ions and submicron particles studied in excised lung.

Direct measurements of bronchial deposition in ventilated pig lungs are reported for radon daughter ions and condensation nuclei. Comparisons are made with deposition calculated from the theory of particle diffusion in steady, laminar air-flow. In segmental bronchi, the observed deposition of condensation nuclei was within about 25% of that calculated. Deposition was greater by up to a factor 2 in main stem and lobar bronchi. Deposition in the trachea depended upon the entrance conditions set by vocal cords. For thorium-B ions, deposition in segmental bronchi was a factor 4 less than calculated, apparently due to rapid hygroscopic growth. Clearance rates by dissolution from bronchial epithelium in vivo for lead and bismuth ions are also reported. Approximately 10% of 212Pb ions diffused into blood with a half-time of about 70 min and 30% of 212Bi ions with a much shorter half-time of about 7 min. The implications of these data in the calculation of radiation dose from inhaled radon daughters are discussed.

Aerosols↗

PubMed2003

Education and income: double-edged swords in the epidemiologic transition of cardiovascular disease.

The 2002 World Health Report warns that the allies of poverty and ignorance are joining forces with the new formidable enemies of health. This describes the epidemiologic transition of burden of disease from infectious and parasitic diseases to that of noncommunicable diseases. All parts of the world, with the possible exception of sub-Saharan Africa, have well-established epidemics of coronary heart disease and stroke. Hypertension contributes significantly to mortality everywhere and is a leading global problem. Education and wealth have strong influences on the epidemiologic transition and might serve as a double-edged sword of benefit and risk. While improved education and enhanced resources are necessary to reduce infectious, parasitic, and perinatal diseases, these factors are also associated with adoption of deleterious health behaviors, which lead to the atherosclerotic diseases. The diffusion of innovation theory describes the early adoption of unhealthy lifestyles in the educated and wealthy, who soon recognize the costs to their community and modify these lifestyles. The uneducated poor may adopt these unhealthy lifestyles later, but, once that occurs, are left with higher risk and burden of cardiovascular disease. One possible reason for this is that discretionary income and the desire for modern conveniences quickly attract unhealthy products (tobacco, high fat/high salt foods) and unhealthy behaviors (sedentary entertainment transportation without physical exertion). The commercial interests of these products have been efficient and effective in delivering their messages to developing societies. Heart health organizations must be more aggressive in their assessment of needs for programs, education of people over a broad range of education levels, assurance of access to heart health services, alteration of the environment to facilitate heart health, and the development of policies and laws to limit deleterious products and behaviors. These late-adopter communities are assumed to require additional efforts and services to counterbalance deleterious influences. Sub-Saharan Africa is the only WHO region in which cardiovascular disease is not the leading cause of death. There is no precedent to support the notion that Africa will, without special efforts, avoid progression to later stages of the epidemiologic transition. The goal of improved education and eradication of poverty in Africa should not and need not carry the unhappy consequence of a cardiovascular disease epidemic.

Africa South of the Sahara↗

PubMedDate not supplied

Ionic versus nonionic paramagnetic contrast media in differentiating between postoperative scar and recurrent disk.

BACKGROUND AND PURPOSE: In theory, ionic solutes diffuse more slowly in cartilage than do nonionic solutes. We tested the hypothesis that the contrast ratio between scar and recurrent disk fragment on MR images is greater after IV administration of an ionic rather than a nonionic contrast medium when a clinical dose is used. METHODS: Twenty patients who had recurrent lumbar disk herniation were enrolled in this study. The enhancement of epidural scar and recurrent disk fragment was measured at 5, 25, 40, and 50 min after IV injection of ionic and nonionic contrast media (0.1 mmol/kg) RESULTS: The enhancement was consistently and significantly higher for scar than for recurrent disk fragment, although the contrast ratio between scar and recurrent disk fragment decreased between 5 and 50 min after the administration of each contrast medium. No significant difference was shown between ionic and nonionic contrast media in the enhancement of recurrent disk fragment at 5, 25, 40, and 50 min after injection. The contrast ratio between scar and recurrent disk fragment was not a significant difference at 5, 25, and 40 min after administration of both contrast media. At 50 min, the contrast ratio between scar and recurrent disk fragment was 1.32 +/- 0.41 with ionic contrast medium and 1.20 +/- 0.56 with nonionic contrast medium. The difference was significant. CONCLUSION: The contrast ratio between scar and recurrent disk fragment is affected by the timing of the imaging. Images obtained immediately after the injection of each contrast medium showed a greater contrast ratio than did delayed images. In addition, with the ionic medium, this difference was greater than with nonionic medium at 5, 25, 40, and 50 min after injection and that difference reached statistical significance at 50 min.

Cicatrix↗

PubMed2005

A community hospital acute pain service.

This article provides readers with a guide to developing and implementing an acute pain service in a community hospital. Kanter's theory of innovative diffusion is used to frame the author's experiences as a lead nurse in two community hospital acute pain services. Health-care providers recognize the importance of quality pain assessment and management. One initiative for improving pain management has been the implementation of an acute pain service (APS). In Canada, most university-affiliated teaching hospitals have now developed an APS to improve pain management. Community hospitals, however, have only recently begun to adopt the concept. Improving pain management through an APS provides an excellent opportunity for nursing leadership at all levels. Nursing administration may take the lead in proposing the idea and benefits of acquiring an APS. An advanced practice nurse can provide leadership through the coordination and provision of enhanced pain management as a lead nurse in an APS. Staff nurses can provide leadership in improving pain management on a daily basis and ensuring that quality pain care reaches the bedside, Nursing practice is at the core of making a difference in pain management.

Hospitals, Community↗

PubMed2006

Health information Hispanic outreach in the Texas Lower Rio Grande Valley.

PURPOSE: This paper provides an overview of the two-year Texas Lower Rio Grande Valley Health Information Hispanic Outreach (HI HO) project. The project included a needs assessment, four pilot projects, and focus groups on the use of MedlinePlus and MedlinePlus en español. The needs assessment included a survey of physicians' information usage and a review of the circuit librarian program that had been established in 1989. The pilot projects were located at a high school, a rural health clinic, an urban health clinic, and a community center. Diffusion of innovation theory provided a framework for interpreting the results of the pilot projects. METHODS: The survey of physicians' information usage partially replicated a similar 1990 survey. The review of the circuit librarian program included usage statistics, interviews of administrators, and a survey of participants. Pilot project methodology varied by site. At the high school, four students were trained to instruct their peers in the use of MedlinePlus. At the two clinics, a computer workstation was installed for patients to access MedlinePlus. At the community center, staff were trained to use MedlinePlus en español to train community residents. Project evaluation included surveys, focus groups, and interviews. Indicators of success included increased level of consumer use of MedlinePlus, reports by key informants and consumers of how MedlinePlus was used, reports about training, and development of self-sustaining activity. RESULTS: The physician survey documented usage of health information resources in 2002 compared to 1990. The review of the circuit librarian program documented the change in program usage between 1989 and 2003. The pilot project at the high school was the most successful of the four pilot projects in introducing MedlinePlus to a large number of people, followed by the community center project. In the high school and community center projects, the participating institutions had reinforcing educational missions and paid staff who were highly motivated to achieve the project goals. The computer workstations projects at the two clinics were less successful, due in part to limited staff commitment and conflicting priorities. CONCLUSIONS: The HI HO project tested methods of reaching the Hispanic community in the Lower Rio Grande Valley region of Texas. The four HI HO pilot projects varied in achieving their stated objectives. But taken as a whole, the HI HO project significantly contributed to a better understanding of health information outreach to the Hispanic community, knowledge that should be useful to others with similar outreach activities.

Ambulatory Care Facilities↗

PubMed1989

Marketing smokeless tobacco in California communities: implications for health education.

In the first phase of a 5-year research project aimed at curtailing smokeless tobacco use among youth, we examined the marketing of smokeless tobacco within California. Observational data were collected from almost 200 retail stores located near high schools and colleges in 14 California counties. Interviews were conducted with over 100 school personnel and youth leaders in 13 counties and with seven retailers from 4 counties. Overall, 81% of the stores in the sample carried smokeless tobacco, and even in urban areas most stores (71%) had these products for sale. Urban stores were more likely to have materials promoting them (e.g., posters, displays, coupon offers). Almost all (98%) stores that carried smokeless tobacco sold moist snuff. Most (78%) school personnel and youth leaders, especially in urban areas, were aware of advertisements for it, particularly on television and in magazines. Rogers' theory regarding the diffusion of innovations was the basis of the discussion of our results. The implications of marketing for the development of health education programs are examined.

Adolescent↗

PubMedDate not supplied

Organizational integrative mechanisms and adoption of innovations by nurses.

The relationship between organizational activities and structures that increase information flow (integrative mechanisms) and nurse adoption of innovations (research results) was studied using Rogers' theory of innovation diffusion. Analysis of variance demonstrated a significant interaction effect between level of integrative mechanism use, institution size, and nurse adoption of innovations. In small hospitals a higher level of integrative mechanism use was related to increased nurse innovation adoption; however, in large hospitals the opposite was found. Of the five categories of integrative mechanisms identified, only Research Conduct and Publication were significantly related to innovation adoption, and then only in small hospitals. In large hospitals, Conference and Presentation, Position and Committee, and Publication categories were demonstrated to be significantly, but negatively, related to innovation adoption among nurses.

Communication↗

PubMed1976

A possible mechanism for enhancement of increased production of tumor angiogenic factor.

It is suggested that anoxic conditions may enhance the transformation of tumor cells to increase production of tumor angiogenic factor. The theory of oxygen diffusion into a spherical mass is used to calculate an upper bound for the critical size at which anoxia begins to develop in the center of an avascular clone of tumor cells. The predicted size is in line with experimental observations of the maximum size of avascular tumors.

Angiogenesis Inducing Agents↗

PubMed1999

Classical diffusion and quantum level velocities: systematic deviations from random matrix theory.

We study the response of the quasienergy levels in the context of quantized chaotic systems through the level velocity variance and relate them to classical diffusion coefficients using detailed semiclassical analysis. The systematic deviations from random matrix theory, assuming independence of eigenvectors from eigenvalues, are shown to be connected to classical higher-order time correlations of the chaotic system. We study the standard map as a specific example, and thus the well-known oscillatory behavior of the diffusion coefficient with respect to the parameter is reflected exactly in the oscillations of the variance of the level velocities. We study the case of mixed phase-space dynamics as well and note a transition in the scaling properties of the variance that occurs along with the classical transition to chaos.

Journal Article↗