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PubMed2002

Static and dynamic views of visual cortical organization.

Without the aid of modern techniques Cajal speculated that cells in the visual cortex were connected in circuits. From Cajal's time until fairly recently, the flow of information within the cells and circuits of visual cortex has been described as progressing from input to output, from sensation to action. In this chapter we argue that a paradigm shift in our concept of the visual cortical neuron is under way. The most important change in our view concerns the neuron's functional role. Visual cortical neurons do not have static functional signatures but instead function dynamically depending on the ongoing activity of the networks to which they belong. These networks are not merely top-down or bottom-up unidirectional transmission lines, but rather represent machinery that uses recurrent information and is dynamic and highly adaptable. With the advancement of technology for analyzing the conversations of multiple neurons at many levels in the visual system and higher resolution imaging, we predict that the paradigm shift will progress to the point where neurons are no longer viewed as independent processing units but as members of subsets of networks where their role is mapped in space-time coordinates in relationship to the other neuronal members. This view moves us far from Cajal's original views of the neuron. Nevertheless, we believe that understanding the basic morphology and wiring of networks will continue to contribute to our overall understanding of the visual cortex.

Animals↗
PubMed1991

Psychobiology and psychiatric nursing: a philosophical matrix.

Over the past several years, conceptualizations of the mind have been challenged by a knowledge explosion in the psychobiological sciences. Such new knowledge continues to fuel a paradigm shift in psychiatry away from traditional psychodynamic models of the mind and toward ones balanced with a psychobiological dimension. The combination of psychodynamic and psychobiological fields of knowledge offers an opportunity for a holistic perspective on the human experience. Psychiatric nursing faces the challenge of integrating this new knowledge for the enrichment of its practice. To accomplish this complex task, issues need to be addressed in many areas critical to psychiatric nursing. Three areas are discussed in this article and include philosophy, communication of philosophy, and testing of philosophy. This article concludes with a discussion of some potential mechanisms to deal with the tensions generated by a paradigm shift in psychiatric nursing.

Biology↗
PubMed1995

Morphostasis and immunity.

Scientists have traditionally been resistant to fundamental changes in perspective. New ideas are rejected if they challenge essential, accepted paradigms. Here I present a concept that, I believe, represents a paradigm shift in the way self/non-self discrimination is perceived. Traditional opinion has it that lymphocytes carry out this discrimination. I propose an alternative view. Self/non-self discrimination is driven by mechanisms closely related to those that lead to cell sorting in disaggregated embryos. Lymphocytes are only used to classify cells according to their mode of death (apoptosis or necrosis). The hypothesis outlines the process of morphostasis (tissue homeostasis). It fills in much detail about the gradual evolution of the mammalian immune system. Earlier versions of this hypothesis have been reflexly rejected by numerous journals. Until recently, I too was unsure of the validity of the core concept. Recent publications have dispelled this doubt from my mind. A paradigm shift is due.

Animals↗
PubMed2005

Formative assessment: a key to deep learning?

A paradigm shift in assessment culture has emphasized the importance of formative assessment. The existing evidence supports the identification of feedback as the central component of formative assessment. Feedback provides information about the existing gap between the actual and desired levels of performance. The existing evidence suggests various characteristics of effective feedback, for example, ensuring that feedback is construct-referenced and student referenced. An exploration of the existing educational literature provides evidence for the emphasis on formative assessment. This paper evaluates the pedagogical implications of formative assessment to deep learning. A constructivist approach, emphasizing the principles of adult learning and placing emphasis on the student is advocated. However, in applying the wider educational literature to healthcare, it is questioned if the paradigm shift in assessment culture has occurred as the majority of the existing literature is centred on summative assessment.

Educational Measurement↗
PubMed2000

Successful aging: implications for oral health.

The past few years have seen a growing emphasis in gerontology on the concept of "successful" or "robust" aging. This represents a major paradigm shift in the field from a focus on declines in physical and social functioning, assumptions of the aging process as a downward spiral, and studies on how to manage these declines. Leading the way toward this new perspective on aging, the MacArthur Studies of Successful Aging asked the fundamental question: "What genetic, biomedical, behavioral, and social factors are crucial to maintaining health and functional capacities in the later years?" These studies examined longitudinally a large cohort of independent elders on several physical, cognitive, emotional, and social parameters. Other researchers have focused on the theme of robust aging; however, common predictors have emerged, such as remaining active physically and cognitively, maintaining social contacts, and avoiding disease. This research is timely, given the expanding population of the oldest old, and with successive cohorts demonstrating the "compression of morbidity" phenomenon. Such a paradigm shift is critical in geriatric dentistry as well, where successful aging is evident in the growing number of older adults who have retained their natural dentition into advanced old age. This presentation draws parallels between successful aging at the systemic and oral health levels, with illustrations from epidemiologic studies that demonstrate trends in improved health and quality of life among newer cohorts of older adults.

Adult↗
PubMedDate not supplied

Don't wait for the crisis. Finding the paradigm in the pattern. Interview by Joe Flower.

Joel Barker has been talking about the future for a long time past. His message: Change happens. Change happens as paradigms shift--the way we picture the universe shifts, and life is different. Relationships and values change their meaning. And because they mean something different, we change them. Barker's question is: How do you manage this change? How do you get ahead of it, and not lag behind it? How do you become its partner and not its victim? These are challenging questions, and hundreds of corporations have invited Barker to come ask them. His client list ranges over much of the Fortune 500--from IBM and DuPont to Honeywell, Boeing, and Gulf Oil--and it includes such healthcare clients as Merck, Upjohn, the Mayo clinics, and the Sisters of Charity. Barker has worked with these questions for the past 17 years, first as director of the pioneering Future Studies Department of the Science Museum of Minnesota, then as president of Infinity Limited, Inc. He has put his answers into a video, "Discovering the Future," and two books, the 1985 Discovering the Future: The Business of Paradigms, and the new Future Edge: The Paradigm Principles Guide for the '90s. We spent a recent morning talking with him about what a paradigm is, and what happens when a paradigm shifts.

Hospital Administration↗
PubMed2005

Partial-breast treatment for early breast cancer: emergence of a new paradigm.

Although hailed as a paradigm shift, the breast conservative treatment that emerged in the 1980s was in fact an extension of the Halstedian concept, wherein whole-breast irradiation (WBI) compensated for the limited surgery. Observations that 80-90% of breast recurrences after breast conservative surgery and WBI occur in the tumor bed questions the need for protracted elective WBI, and provides the rationale for accelerated-partial-breast irradiation (APBI) of small cancers without adverse features predisposing to multicentric recurrence. APBI can be given over a week with various external beam, intraoperative or brachytherapy (interstitial or MammoSite) techniques. Since the approval of MammoSite by the US FDA in May 2002, a surge of interest has been evident, with 4,000 cases treated using this technique in the past 2 years. Several phase II APBI brachytherapy studies show that 4 to 7-year breast control rates (95%), survival and cosmetic outcome obtained from more than 600 appropriately selected women are comparable to matched or historic controls receiving WBI. The 2 to 3-year interim results of two ongoing randomized trials do not show any early detriment with APBI. If mature results of randomized trials confirm equivalence of APBI to conventional WBI in selected women, it would mark a paradigm shift and a major advance in treatment. This would allow many more women to opt for breast conservation, resolve the dilemmas regarding chemotherapy and radiotherapy sequencing and perhaps would be more cost effective.

Brachytherapy↗
PubMed2000

Historical changes in the postoperative treatment of appendicitis in children: impact on medical outcome.

BACKGROUND/PURPOSE: The introduction of managed care in the 1980s caused increased pressure to reduce costs for hospitalized patients. The authors hypothesized that these market forces have resulted in a decreased hospital stay and utilization of sophisticated diagnostic testing in children treated for appendicitis. If true, the impact of this paradigm shift on patient outcome is unknown. METHODS: Hospital records for 913 pediatric patients treated for appendicitis from 1974 to 1998 were reviewed retrospectively. Patients were stratified into those with perforated appendicitis (PA) and nonperforated appendicitis (NPA). Demographics, perioperative hospital course, diagnostic testing, complications, and long-term outcomes were analyzed after stratification into time intervals. RESULTS: Over time, children with NPA were treated with shorter antibiotic courses (P<.05) and were placed on a regular diet earlier (P<.05). These changes in treatment resulted in an earlier discharge (P<.05). The amount of time to become afebrile with a normal white blood cell count (WBC) did not change over time. Children with PA exhibited similar results with shorter antibiotic courses (P<.05), earlier dietary intake (P<.05) and earlier hospital discharge (P<.05) over time. In all children with appendicitis there was no significant difference in the rate of wound infections, abscesses requiring drains, readmission, or reoperations overtime. The utilization of abdominal radiographs (83%) and ultrasonography (USN; 40%) was high and remained unchanged over time. Utilization of computed tomography (CT scan) was low (4.3%) in the early decades and was not used as a preoperative test from 1991 to 1994. Given the high diagnostic accuracy of a pediatric surgeon for this disease, Bayesian analysis indicates that USN utilization rates should be 15%. CONCLUSIONS: The market pressures of managed care have resulted in a new treatment paradigm with an earlier discharge of all children with appendicitis. There has been no concomitant increase in the complication rate in either group as a result of this paradigm shift. Bayesian analysis indicates that USN and abdominal radiographs are overutilized in our institution.

Adolescent↗
PubMed2002

PACS monitors: an evolution of radiologist's viewing techniques.

When initially evaluating picture archiving communication systems (PACS) many radiologists try to duplicate the film environment and believe that multiple monitors are required to maintain the productivity of the radiologist. The authors were under the same impression initially but found that they underwent a paradigm shift over a period of time. This report documents the evolution that the radiologists underwent. The author's department consists of 28 diagnostic radiologists and 21 residents who actively read cases on a PACS. The department has been filmless for 6 months, although they have been reading soft copy films for 2 years. All modalities except mammography are included. The authors conducted interviews with both attending radiologists and residents to evaluate the change in methodology from the preconceptions to initial use to current use. The number and kind of monitors preferred for plain films, ultrasound scan, computed tomography (CT), and magnetic resonance imaging (MRI) were recorded. Additionally, viewing methods of different modalities were discussed. The authors found that there was a decrease in the number of monitors from preconceptions to actual use. Furthermore, to a lesser degree, there is a reduction of monitors used initially to that which is currently being used. The style of viewing cross-sectional images has changed. There has been a decrease in the number of images displayed on each monitor. The use of the roller ball on the mouse has affected this viewing style. Changing from a film-based reading environment to PACS environment not only brings about change in the overall technology in image delivery but also in the viewing techniques by radiologists. At our institution we have evolved from initially expecting to use 4 monitors all the time to actually preferring 2 monitors and occasionally 1 monitor to view images. Presentation software and viewing aids such as the roller ball on a mouse for viewing CTs in stack mode are key contributions to this paradigm shift. The decrease in monitors makes PACS more affordable and will allow further penetration of filmless radiology. The authors have found that after using PACS, radiologists prefer using 2 monitors. The style of reading films has changed with experience. Hospitals that plan to purchase PACS should consider this and ensure that the vendor has presentation software that optimizes the 2 monitor system.

Computer Terminals↗
PubMed2006

Educating to improve population health outcomes in chronic disease: an innovative workforce initiative across remote, rural and Indigenous communities in northern Australia.

INTRODUCTION: Like Indigenous populations in other countries, an epidemic of chronic disease has swept across Australia's Indigenous communities in the past decade. The Northern Territory and Queensland health departments initiated preventable chronic disease strategies in 1999 and 2001, respectively. Yet finding innovative ways to translate this to the health workforce was challenging. Through support from the Australian Government, three universities, two health departments and two Indigenous organisations worked in partnership to improve workforce capacity in remote and rural communities through innovative education. METHODS: The methods included: (i) a training needs analysis consisting of 76 semi-structured interviews with key informants, and 35 surveys of remote staff; (ii) a literature and resource review; (iii) the development of a curriculum framework using: the existing competencies and standards across the health disciplines; the identified workforce needs; and what the workforce can impact upon; (iv) a multidisciplinary workshop with 35 educators across northern Australia that resulted in the basis for agreement of the final curriculum content and framework; (v) the development of a chronic disease self-assessment tool that was piloted with remote health staff; (vi) an assisted integration process for key stakeholders. An evaluation framework was also developed, as a separate project, in conjunction with the project partners during this time. RESULTS: This project identified that a paradigm shift is required in the way in which we educate the entire health workforce to deal effectively with the impact of chronic disease across remote, rural and Indigenous populations. In particular a need was found to educate the educators in the chronic care model and in using a population health approach. The training needs analysis identified very little difference between the education and training needs across the rural and remote health disciplines; it was perceived that they managed chronic disease fairly well yet found prevention and early detection to be at the 'hard end'. The main barriers identified were the demands of acute care over chronic disease management, compounded by high workforce turnover in remote areas. The curriculum framework, in particular the domains of remote practice, is being used by several Australian universities, health departments and non-government organisations in adapting their existing or new education programs. The self-assessment tool was based on the curriculum outcomes and was piloted in 2005 and found to be very useful for pre- and post-training purposes and as a discussion starter for all disciplines and groups. CONCLUSIONS: A practical curriculum framework now exists to integrate a population health approach for the prevention and early detection of chronic disease when educating the primary healthcare workforce. It is relevant to all health disciplines and is flexible in that it can be adapted, or adopted, depending on the educational needs of the disciplinary group. It is being imbedded into numerous undergraduate, postgraduate, and professional development programs in Australia. It includes: the core learning outcomes expected of any workforce, resources, and a self-assessment tool in chronic disease. These tools are assisting educators in the required paradigm shift required of the workforce to alter the single disease based practice model towards a comprehensive and integrated population based approach required for the workforce in the 21st century.

Chronic Disease↗
PubMedDate not supplied

Transcutaneous lower eyelid blepharoplasty with fat excision: a shift-resisting paradigm.

OBJECTIVE: To prove through our experience that the use of transcutaneous lower eyelid blepharoplasty results in negligible incidence of unacceptable scar and eyelid malposition and that the overall lower eyelid contour is acceptable. A detailed overview of the lower eyelid anatomy and a discussion of the "aging" eyelid are further discussed. DESIGN: Retrospective, observational study. The study population comprised 50 patients (100 eyes) seen at the McCollough Plastic Surgery Clinic, Gulf Shores, Ala, between 2002 and 2003 (45 women and 5 men), who had undergone transcutaneous lower eyelid blepharoplasty with fat excision. Lower eyelid blepharoplasty was performed by the senior surgeon (E.G.M.), and the surgical technique was identical in all cases. The patients were followed up for a minimum of 6 months and a maximum of 2 years. Patients were selected on the basis of return visits to record the findings, documented by consecutive digital photos. By comparing standard blepharoplasty digital views, the patients were assessed by 3 independent unbiased plastic surgeons. This study was performed in a private practice setting. The main outcome measure was mean score for the presence of unacceptable scarring, the presence of lower eyelid malposition, and the overall appearance of the eyelid after transcutaneous lower eyelid blepharoplasty, as assessed with the Garcia-McCollough Scale for Lower Eyelid Appearance. RESULTS: The 50 patients were retrospectively reviewed and analyzed by a group of 3 unbiased plastic surgeons, and there was negligible evidence of lower eyelid contour abnormality, lower eyelid malposition, or easily visible scars. CONCLUSIONS: Transcutaneous lower eyelid blepharoplasty with fat excision is a time-tested method of correcting the undesirable sequelae of the aging eye. This technique not only is a safe and effective manner to rejuvenate the lower eyelid but also results in virtually nonexistent ill effects.

Adipose Tissue↗
PubMed2006

Depression in late-life: shifting the paradigm from treatment to prevention.

Late-life depression is very common and is associated with high rates of morbidity and mortality. While the field of geriatric psychiatry is focused on depression treatment, prevention is an enticing option. Prevention of late-life depression would decrease both emotional suffering and depression-associated morbidity and mortality and may decrease dependence on non-mental health professionals to detect depression and to initiate a treatment referral. This paper will review current thinking on prevention research with a particular focus on its application to late-life depression. To illustrate these issues, we discuss recent and ongoing clinical trials of interventions to prevent depression in two populations of older persons: those with age-related macular degeneration (AMD) and those with cerebrovascular disease.

Aged↗
PubMed2006

A shift of paradigm: from noradrenergic to dopaminergic modulation of learning?

d-Amphetamine coupled with behavioral training has been effective for improving functional recovery after stroke. d-amphetamine acts on multiple brain transmitter systems, but the recovery enhancing effect has been attributed to its noradrenergic actions. Another potent modulator of learning is dopamine, which may also enhance stroke recovery in humans. Based on data from previous studies of our group, we compared the learning enhancing effects of d-amphetamine with a more selective dopaminergic substance (levodopa) in identical protocols. Using a prospective, randomized, double-blind, placebo-controlled design, we had taught 60 male healthy subjects a miniature lexicon of 50 concrete nouns over the course of five consecutive training days using an associative learning principle. Subjects had received either d-amphetamine (0.25 mg/kg), levodopa/carbidopa (fixed dose of 100/25 mg), or placebo 90 min prior to training on each of the 5 days. Novel word learning was significantly enhanced in both the d-amphetamine and levodopa groups as compared to the placebo group. The learning superiority was maintained at the two re-assessments (1 week and 1 month post training). Both d-amphetamine and levodopa are thus potent drugs in enhancing learning in humans. We here discuss why the efficiency of both d-amphetamine and levodopa may be related to dopaminergic rather than noradrenergic actions.

Adrenergic Agents↗
PubMed2005

Shifting the paradigm of coral-reef 'health' assessment.

Coral reefs are in crisis. Globally, our reefs are degrading at an accelerating rate and present methodologies for coral-reef 'health' assessment, although providing important information in describing these global declines, have been unable to halt these declines. These assessments are usually employed with no clear purpose and using uncorrelated methods resulting in a failure to prevent or mitigate coral reef deterioration. If we are to ever successfully intervene, we must move beyond the current paradigm, where assessments and intervention decisions are based primarily on descriptive science and embrace a paradigm that promotes both descriptive and mechanistic science to recognize a problem, and recognize it before it becomes a crisis. The primary methodology in this alternative paradigm is analogous to the clinical and diagnostic methodologies of evidence-based medicine. Adopting this new paradigm can provide the evidence to target management actions on those stressors currently impacting reef ecosystems as well as providing a means for proactive management actions to avert irreversible habitat decline.

Animals↗