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PubMed2006

Nurses in alternative health care: integrating medical paradigms.

The article is concerned with nurses in Israel who incorporate alternative health care practices into their work, and considers strategies used by them to reconcile a variety of theoretical and practice traditions. The analysis utilizes boundary theory and focuses on the following boundaries: territorial, epistemological, authority, and social. In-depth narrative interviews were carried out in 2004 with 15 nurses who were working or recently worked in both biomedical and complementary and alternative medicine (CAM) settings. The findings show that nurses using CAM practices do not seek to change the epistemological and authority boundaries of biomedicine. Even so many believe that CAM methods should be included within the cognitive boundaries of biomedicine. They are not disturbed that most of these techniques have not passed the test of biomedical research criteria, though they feel blocked by physicians who keep the cognitive boundaries of biomedicine closed.

Adult↗
PubMed1978

A note on the "Brody-effect".

The effect of a perfectly conducting sphere simulating the intracavitary blood mass on a dipole source located at the interface with the outer tissue (myocardium) is studied, utilizing image theory. The resulting enhancement factor is found to be a function of the field point location and is not a constant, as previously reported by Brody and by Rush and Nelson.

Blood↗
PubMed1989

A mathematical modelling study of epiphyseal cartilage calcification.

Recent studies in this laboratory have suggested that proteoglycan may function as a Ca ion-exchanger in the calcification of epiphyseal growth plate cartilage. Specifically, it has been proposed that phosphate liberated from hypertrophic chondrocytes may displace calcium ions bound to the anionic groups of proteoglycans, thereby raising the Ca x PO4 activity product above the threshold for precipitation of hydroxyapatite. In order to determine whether this mechanism is quantitatively feasible, a mathematical model of the interaction between Ca, Na, proteoglycan and phosphate has now been developed. This model is based on a general binding theory, and utilizes previously-determined values for the binding constants of the Ca-proteoglycan interaction, inhibition constants for the effect of Na and phosphate on this interaction, and literature values for the concentrations of proteoglycan, Na and Ca in epiphyseal cartilage. Using this approach, it was predicted that the free Ca concentration in epiphyseal cartilage in the absence of phosphate will be 1.55 mM. At 0.7 mM phosphate, the approximate concentration in non-calcified cartilage matrix, the free Ca concentration will be 2.40 mM, corresponding to a Ca x PO4 product of 1.68 (mM)2. In order to achieve a Ca x PO4 product sufficient for spontaneous precipitation of hydroxyapatite [approximately 4.3 (mM)2], a phosphate concentration of approximately 1.40 mM is required. Therefore, calcification of epiphyseal cartilage matrix by the mechanism described above will require an approximate doubling of the phosphate concentration in the pre-calcifying zones, indicating that the release of a fraction of the intracellular phosphate could trigger the calcification process.

Calcification, Physiologic↗
PubMed2003

Evaluation of the reaction kinetics of CORTOSS, a thermoset cortical bone void filler.

The primary objective of this research is to evaluate the reaction kinetics of CORTOSS(TM), a thermoset, Bis-GMA (2,2-bis[4-(2-hydroxymethacryloxypropyl) phenyl]propane) composite system as a function of time, material storage temperature and the temperature of the surrounding environment (site temperature). This study utilizes probability theory to predict the percentage of bifunctional monomers with 0,1 and 2 functional groups that have been reacted. This is a strong indicator of the potential for leaching unreacted components. A differential scanning calorimeter (DSC) was used to measure the isothermal enthalpy at varying site temperatures. After isothermal monitoring, the samples were dynamically heated from the respective isothermal temperature to 175 degrees C at 15 degrees C/min to measure the residual enthalpy from the unreacted functional groups. The experimental results indicate that the degree of conversion for this bifunctional system ranged from 76% to 86%. Applying probability theory it has been determined that approximately 95% of the bifunctional monomers are present with at least one double bond reacted and up to 5% of monomers remain unreacted. This is consistent with theoretical values postulated for various diffusion controlled thermoset systems (Macromolecules 32 (1999) 3913). Overall, curing under physiological conditions yielded a faster reaction rate and a significantly higher degree of conversion as compared to the lower site temperature conditions.

Benzeneacetamides↗
PubMed1998

The role of child maltreatment and attachment style in adolescent relationship violence.

Utilizing attachment theory as a basis for conceptualizing close relationships among adolescents, this study investigated two important relationship risk factors (child maltreatment, and adolescent self-perceived insecure attachment style) as predictors of "offender" and "victim" experiences in youth relationships. In addition to considering the influence of these risk factors, we further considered their interaction in predicting conflict in close relationships. Of interest was the extent to which attachment styles may function as a moderator of the relationship between childhood abuse and current abuse in teen close relationships. High school students (N = 321) in grades 9 and 10 completed questionnaires tapping their histories of maltreatment, currently viewed styles of attachment, and conflict in close relationships over the past 6 months. Maltreatment alone emerged as the most consistent predictor, accounting for 13-18% of the variance in male's physically, sexually, and verbally abusive behaviors; in contrast, it was not highly predictive of female's abusive behaviors. Maltreatment was predictive of victimization experiences for both males and females. Attachment style did not substantially add to the prediction of relationship conflict beyond maltreatment; however, avoidant attachment style emerged repeatedly as a significant predictor of female abusiveness and victimization. Attachment self-ratings were found to function as a moderator of child maltreatment in predicting primarily male coercive behavior towards a relationship partner as well as predicting male's experience of coercion from a partner. Thus, the presence of childhood maltreatment and adolescent self-perceived insecure attachment style applies predominantly to male youth. The implication of these gender differences for understanding relationship violence is discussed.

Adolescent↗
PubMed2004

Care planning for pressure ulcers in hospice: the team effect.

OBJECTIVE: The standards of care for patients at risk for or with a pressure ulcer in hospitals and nursing homes focus on prevention and ulcer healing using an interdisciplinary approach. Although not a primary hospice condition, pressure ulcers are not uncommon in dying patients. Their management in hospices, particularly the involvement of family caregivers, has not been studied. The objective of this study is to identify the factors that influence care planning for the prevention and treatment of pressure ulcers in hospice patients and develop a taxonomy to use for further study. METHODS: A telephone survey was conducted with 18 hospice directors of clinical services and 10 direct-care nurses. Descriptive qualitative data analysis using grounded theory was utilized. RESULTS: The following three themes were identified: (1) the primary role of the hospice nurse is an educator rather than a wound care provider; (2) hospice providers perceive the barriers and burdens of family caregiver involvement in pressure ulcer care to be bodily location of the pressure ulcer, unpleasant wound characteristics, fear of causing pain, guilt, and having to acknowledge the dying process when a new pressure ulcer develops; and (3) the "team effect" describes the collaboration between family caregivers and the health care providers to establish individualized achievable goals of care ranging from pressure ulcer prevention to acceptance of a pressure ulcer and symptom palliation. SIGNIFICANCE OF RESULTS: Pressure ulcer care planning is a model of collaborative decision making between family caregivers and hospice providers for a condition that occurs as a secondary condition in hospice. A pressure ulcer places significant burdens on family caregivers distinct from common end-of-life symptoms whose treatment is directed at the patient. Because the goals of pressure ulcer care appear to be individualized for a dying patient and their caregivers, the basis of quality-of-care evaluations should be the process of care rather than the outcome of an incident pressure ulcer.

Hospice Care↗
PubMed2005

A suite of 2H NMR spin relaxation experiments for the measurement of RNA dynamics.

A suite of (2)H-based spin relaxation NMR experiments is presented for the measurement of molecular dynamics in a site-specific manner in uniformly (13)C, randomly fractionally deuterated ( approximately 50%) RNA molecules. The experiments quantify (2)H R(1) and R(2) relaxation rates that can subsequently be analyzed to obtain information about dynamics on a pico- to nanosecond time scale. Sensitivity permitting, the consistency of the data can be evaluated by measuring all five rates that are accessible for a spin 1 particle and establishing that the rates obey relations that are predicted from theory. The utility of the methodology is demonstrated with studies of the dynamics of a 14-mer RNA containing the UUCG tetraloop at temperatures of 25 and 5 degrees C. The high quality of the data, even at 5 degrees C, suggests that the experiments will be of use for the study of RNA molecules that are as large as 30 nucleotides.

Carbon Isotopes↗
PubMed1998

Revised Structures of N-Substituted Dibrominated Pyrrole Derivatives and Their Polymeric Products. Termaleimide Models with Low Optical Band Gaps.

This paper describes an unexpected rearrangement/oxidation of N-substituted 2,5-dibromopyrroles upon treatment with HNO(3). The bromides migrate from the 2,5-positions to the 3,4-positions with subsequent oxidation at the 2,5-positions to afford N-substituted 3,4-dibromomaleimides; the structure was confirmed by single-crystal X-ray analysis. The maleimides were then polymerized to the poly(N-substituted-3,4-maleimide)s with copper bronze. This constitutes a revision of structure for the monomers and polymers. The propensity for the dibromide migration was further confirmed by treatment of N-benzyl-2,5-dibromopyrrole under nonoxidative acidic conditions (p-TsOH) to afford N-benzyl-3,4-dibromopyrrole; both the starting material and product structures were confirmed by single-crystal X-ray analysis. Several termaleimides were prepared from pyrrole, maleic anhydride, and citraconic anhydride. These trimeric compounds underwent enormous shifts in their optical absorbance maxima (ca. 200 nm) when bases or nucleophilic solvents were added. Therefore, the termaleimides served as excellent models for the polymeric systems that had undergone shifts of 350-400 nm upon treatment with the same additives. Ab initio Hartree-Fock and density functional theory were utilized to assess the minimum conformation of the trimeric system. Both terminal maleimides appear canted 37 degrees relative to the central maleimide unit. As the two end maleimide units were computationally forced into closer proximity, there was a dipolar stabilization that ensued between the two terminal maleimides with the formation of a 1,3-dioxetane. However, it is unlikely that there could be the formation of an isolable 1,3-dioxetane due to the large energy difference between the canted structure and the dioxetane. A significant decrease in the HOMO-LUMO energy of 13 kcal/mol was calculated upon formation of the 1,3-dioxetane, suggesting that nucleophiles likely move the canted structure more toward a planar form via addition to the alpha,beta-unsaturated carbonyl units.

Journal Article↗
PubMed2005

An ab initio and density functional theory study of keto-enol equilibria of hydroxycyclopropenone in gas and aqueous solution phase.

Keto-enol tautomerism in hydroxycyclopropenone (2-hydroxy-2-cyclopropen-1-one) has been studied using ab initio methods, the B3LYP functional of density functional theory, as well as complete basis set (CBS-QB3 and CBS-APNO) and G3 methods. Absolute and relative energies were calculated with each of the methods, whereas computations of geometries and harmonic frequencies for hydroxycyclopropenone and 1,2-cyclopropanedione were computed in the gas phase but were limited to HF, MP2 and CCSD levels of theory, and the B3LYP functional, in combination with the 6-31++G** basis set. Using the MP2/6-31++G** gas phase optimized structure, each species was then optimized fully in aqueous solution by employing the polarizable continuum model (PCM) self-consistent reaction field approach, in which HF, MP2 and B3LYP levels of theory were utilized, with the same 6-31++G** basis set. In both gas and aqueous solution phases, the keto form is higher in energy for all of the model chemistries considered. The presence of the solvent, however, is found to have very little effect on the bond lengths, angles and harmonic frequencies. From the B3LYP/6-31++G** Gibbs free energy, the keto-enol tautomeric equilibrium constant for 2-hydroxy-2-cyclopropen-1-one <==> 1,2-cyclopropanedione is computed to be K(T)(gas) = 2.35 x 10(-6), K(T)(aq) = 5.61 x 10(-14). It is concluded that the enol form is overwhelmingly predominant in both environments, with the effect of the solvent shifting the direction of equilibrium even more strongly in the favor of hydroxycyclopropenone. The almost exclusive nature of this species is attributed to stabilization resulting from aromaticity. Confirmation is provided by comparison of the simulated vibrational spectra of hydroxycyclopropenone with the measured infrared spectrum in an argon matrix.

Journal Article↗
PubMed1997

Harbinger. I: The development and evaluation of the first PACT replication.

While Assertive Community Treatment (originally known as the PACT program) is now recognized around the world as an effective model for rehabilitation of persons with severe mental illness, this was not the case 20 years ago. Harbinger of Grand Rapids, in Kent County, Michigan, was the first replication of the PACT model which sought fidelity and included an experimental design for assessing effectiveness. The design and results are presented from an initial 30-month and a follow-up 66-month evaluation of Harbinger. The 30-month evaluation showed significant differences favoring Harbinger vs, the control group on independent living, employment, and client functioning. At 66-months, there were fewer experimental-control group differences. The differences in results are analyzed in terms of design and data collection problems, changes in the treatment environment for the control group, and the longitudinal course of mental illness. The discussion focuses on next steps in ACT research, utilizing program theory to better establish the mechanisms for successful intervention models.

Activities of Daily Living↗
PubMed1989

Socialization and attentional deficits under focusing and divided attention conditions.

We conducted two studies to test and refine the hypothesis that, when undersocialized individuals focus on events of immediate interest, they allocate too large a proportion of their processing resources to those events and have little attention available for processing other important events. College students who completed the Socialization (So) scale (Gough, 1960) performed visual and auditory tasks simultaneously under conditions favoring the visual task, an equal division of processing resources between the tasks, or both. In both studies, low-So Ss performed relatively poorly on the auditory task under focusing conditions but displayed no primary task advantage and no significant performance deficits under divided attention conditions. These data support the utility of theories relating antisocial behavior to individual differences in allocation of attention. Low-So Ss' unresponsiveness to secondary events is not a simple function of the reallocation of resources to the primary task or a speed-accuracy trade-off. Moreover, under certain conditions, this deficit may disappear, given substantial practice.

Adult↗
PubMed1997

Initial investigation of mathematical morphology for the digital extraction of the skeletal characteristics of trabecular bone.

OBJECTIVE: To develop a filter utilizing mathematical theory to extract the skeletal patterns of trabecular bone. METHODS: Studies of morphology in the extraction of patterns of calcification in mammograms provided the theoretical framework. Using these studies as a basis, a morphological filter was applied to extract skeletal patterns from digital images of trabecular bone. Sequential images (subset) were combined in a structured fashion to create an aggregate (sumset) which compared with the original images, skeleton and line skeleton images. RESULTS: Binary images of the skeletal patterns in continuous, round and mesh-like forms were obtained from the original images by processing with the skeleton operation using a disc-shaped single structuring element. The line skeleton operation using line structuring elements with constant directions allowed the extraction of linear and discontinuous patterns. Both the skeleton and line skeleton operations extracted binary subset images which depicted skeletal patterns correlating with the operation sequence. CONCLUSIONS: Modification of the morphological filter enhanced the extraction of skeletal characteristics of trabecular bone. A morphological filter may be a useful adjunct in computer-aided structural analysis of bone.

Bone Density↗
PubMed2002

Non-invasive method for quantitative evaluation of exogenous compound deposition on skin.

Topical application of active compounds on skin is common to both pharmaceutical and cosmetic industries. Quantification of the concentration of a compound deposited on the skin is important in determining the optimum formulation to deliver the pharmaceutical or cosmetic benefit. The most commonly used techniques to date are either invasive or not easily reproducible. In this study, we have developed a noninvasive alternative to these techniques based on spectrofluorimetry. A mathematical model based on diffusion approximation theory is utilized to correct fluorescence measurements for the attenuation caused by endogenous skin chromophore absorption. The limitation is that the compound of interest has to be either fluorescent itself or fluorescently labeled. We used the method to detect topically applied salicylic acid. Based on the mathematical model a calibration curve was constructed that is independent of endogenous chromophore concentration. We utilized the method to localize salicylic acid in epidermis and to follow its dynamics over a period of 3 d.

Administration, Topical↗
PubMed2001

Emotions and illness.

AIM: This paper discusses issues central to emotional expression in illness. Its aim is to challenge the psychopathological paradigm currently utilized within healthcare and propose an alternative model based on healthy emotions. BACKGROUND: Emotions are important to human survival. It is argued that most patients will have an emotional response to their illness but anxiety and depression are unlikely to be representative of most patients experience. The paper focuses on two important negative emotions, fear and sadness, and their psychopathological associates, anxiety and depression. Problems of diagnosing anxiety and depression in practice are highlighted. It is contended that emotional reaction to illness is normal and that emotions expressed are likely to hold clues to individual adaptation. It is argued that in health care, emotions should be assessed as healthy reactions to a survival threat and merit study from this perspective if we wish to understand individual patient illness reaction and adaptation better. Literature from cardiology is used to illustrate clinical problems. RATIONALE: Given the present knowledge of emotions, it should be possible to utilize emotion theory as a paradigm for studying human reaction to illness. This in turn could help shape studies on adherence and adaptation. CONCLUSION: The reaction and experience of patient illness is unlikely to be understood through the psychopathology paradigm. A better understanding of patient reaction to their illness is more likely to emerge through the study of basic emotions during acute life-threatening episodes.

Adaptation, Psychological↗
PubMed2004

Nephrology nursing: blurring the boundaries: the reality of expert practice.

BACKGROUND: Expertise in nursing has been widely studied; there have been no previous studies into what constitute expertise in nephrology (renal) nursing. This paper describes a 'real-world' characteristic of expert nephrology nursing practice. AIMS AND OBJECTIVES: This paper, which is abstracted from a larger study into the acquisition and exercise of nephrology nursing expertise, aims to explore the concept blurring the boundaries. DESIGN: The study utilized grounded theory methodology and symbolic interactionism. METHODS: The study took place in one renal unit in New South Wales. Sampling was purposive then theoretical; the sample consisting of six non-expert and eleven expert nurses. Simultaneous data collection and analysis using participant observation, review of nursing documentation and semi-structured interviews was undertaken. RESULTS: The study revealed that only expert nephrology nurses 'blurred the boundaries' of professional nursing practice. They did this by moving intermittently and purposefully, for the benefit of particular patients, into medical domains in the areas of prescribing, dispensing and ordering of pathology tests. Non-expert nurses did not cross these professional boundaries. CONCLUSIONS: Blurring the boundaries was a significant feature of expert nursing practice, and this study was the first to describe explicitly nursing boundaries as two distinct entities; that is, formal and informal. RELEVANCE TO CLINICAL PRACTICE: There are some nephrology nurses who have sufficient knowledge and experience to prescribe some medications and to order certain investigations.

Attitude of Health Personnel↗
PubMed2002

Role of self-efficacy and behaviour change.

Behaviour change is an important concept in relation to health promotion and disease prevention. Self-efficacy has been identified as an important determinant of health behaviour, future health behaviour and health behaviour change. In order to effectively facilitate behaviour change, it is essential that interventions are research based, and emphasize the utility of theory in practice. The effective practice of health promotion and disease prevention requires a full understanding of the processes of patient behaviour. This article presents the role of the nurse in influencing health-related behaviour change. Self-efficacy and related but distinct theories that underpin behaviour change are discussed. The empirical evidence that supports the link between self-efficacy and predictions of health behaviours is also examined.

Health Behavior↗