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How long has it been since you've had a good paradigm shift? No, it's nothing you can plan. Nothing you can simply tick off that perennial list of To Do's tucked away in your pocket or some unoccupied sulcus of your brain. Paradigm shifts simply happen when you are on a journey of discovery. Once they happen, they change forever the way you look at the world.
The practice of neurorehabilitation in the clinic has undergone a paradigm shift as a result of influences from basic and clinical research. I have identified six areas of knowledge that by advancing so rapidly have brought about this paradigm shift: first, the increased understanding of how the CNS is reorganised after training or injury; second, the knowledge of how declarative and procedural memory operates and how this can influence rehabilitation therapy; third, a greater appreciation of the chemical factors that promote learning and neural remodelling; fourth, the fact that computational neuroscience can teach us how complex behaviour can emerge from the interaction of thousands of neurons; fifth, the influence of evidence-based medicine on neurorehabilitation; and sixth, the importance of reliable outcome measures for both injury and treatment. These are young scientific disciplines that offer great opportunities for further research. The complexity of neurorehabilitation will also require greater attention to a substantially neglected problem, the incorporation of techniques that have been proven effective in clinical trials into routine and effective clinical practice.
Treatment of dental caries as an infectious disease will require a paradigm shift in the way dentists and other health care professionals approach prevention and management of the disease. Prevention of dental caries has relied upon patient cooperation and often requires significant lifestyle changes that are at best difficult to implement and maintain or at worst ignored. This paradigm shift in the etiology, prevention, and treatment of dental caries demands that clinicians redirect their energies and emphasis from the "surgical" approach to dental caries to a "medical" strategy that focuses on early (prenatal if possible) risk assessment of the mother and implementation of appropriate therapeutic intervention, including use of antimicrobials, risk assessment of infants at 6 months of age, and a reduction in the levels of caries-producing bacteria. This revolution in how dentists practice and think will require that they develop strategies and curriculum to "retrain" practicing dentists and to train current and future dental students and residents as well as other medical colleagues on the essentials of the paradigm shift.
In the development of any new industry, certain events signal a paradigm shift. Those affected by the "new way" finally seem to grasp that change is inevitable. The paradigm shift has begun for electronic claims submission.
Profound changes are occurring in the strategies that biotechnology-based industries are deploying in the search for exploitable biology and to discover new products and develop new or improved processes. The advances that have been made in the past decade in areas such as combinatorial chemistry, combinatorial biosynthesis, metabolic pathway engineering, gene shuffling, and directed evolution of proteins have caused some companies to consider withdrawing from natural product screening. In this review we examine the paradigm shift from traditional biology to bioinformatics that is revolutionizing exploitable biology. We conclude that the reinvigorated means of detecting novel organisms, novel chemical structures, and novel biocatalytic activities will ensure that natural products will continue to be a primary resource for biotechnology. The paradigm shift has been driven by a convergence of complementary technologies, exemplified by DNA sequencing and amplification, genome sequencing and annotation, proteome analysis, and phenotypic inventorying, resulting in the establishment of huge databases that can be mined in order to generate useful knowledge such as the identity and characterization of organisms and the identity of biotechnology targets. Concurrently there have been major advances in understanding the extent of microbial diversity, how uncultured organisms might be grown, and how expression of the metabolic potential of microorganisms can be maximized. The integration of information from complementary databases presents a significant challenge. Such integration should facilitate answers to complex questions involving sequence, biochemical, physiological, taxonomic, and ecological information of the sort posed in exploitable biology. The paradigm shift which we discuss is not absolute in the sense that it will replace established microbiology; rather, it reinforces our view that innovative microbiology is essential for releasing the potential of microbial diversity for biotechnology penetration throughout industry. Various of these issues are considered with reference to deep-sea microbiology and biotechnology.
Reforms passed by Congress and vetoed by the president during the past year would have accelerated initiatives already transforming Medicare. Operating in a rapidly changing insurance marketplace, Medicare is shifting from a social insurance model toward a private individual insurance model-expanding the number and type of alternative health plans it offers-and growing numbers of beneficiaries are enrolling in these plans. Such reforms, especially if bolstered by legislative reforms that are likely to resurface after the November elections, will rewrite the social contract enacted more than 30 years ago. They require fundamental shifts in ways of thinking about the federal government's responsibilities; the Medicare program's management; relations between the Medicare program and doctors, hospitals, and other health care providers; and the role of beneficiaries in the Medicare program. The likely deferral of further legislative attempts to reform Medicare affords an opportunity to step back and consider these ongoing changes. It is not easy to describe paradigm shifts accurately, but there are advantages to trying. First, conceptual comparisons can allow public discussion to go beyond budget scorekeeping and media soundbites to consider how different the Medicare program will be if it evolves in the new ways being proposed. Second, a conceptual framework can assist health policy analysts to target what to watch for in tracking changes, to assess the tradeoffs involved, and to advise about the needs for refining legislation. This paper includes examples of what to watch for in tracking the implemented changes. The paradigm shifts are summarized below, then described individually in terms of directions of change along a number of continuums. Note that complete paradigm shifts, from one end of a continuum to the other, are seldom completely realized nor even far advanced. But Medicare's ongoing reforms, accelerated by legislative proposals, seem likely predecessors of future changes. For developing this framework, the authors have drawn on the Medicare provisions of the Conference Agreement on the Balanced Budget Act of 1995, the president's proposals as presented in December 1995, and current and proposed Health Care Financing Administration practices.
Medicine has evolved toward rationalization since the Enlightenment, favouring quantitative measures. Now, a paradigm shift toward control through formalization can be observed in health care whose structures and processes are subjected to increasing standardization. However, educational reforms and curricula do not yet adequately respond to this shift. The aim of this article is to describe innovative approaches in medical education for adapting to these changes. The study design is a descriptive case report relying on a literature review and on a reform project's evaluation. Concept mapping is used to graphically represent relationships among concepts, i.e. defined terms from educational literature. Definitions of 'concept map', 'guideline' and 'algorithm' are presented. A prototypical algorithm for organizational decision making in the project's instructional design is shown. Evaluation results of intrinsic learning motivation are demonstrated: intrinsic learning motivation depends upon students' perception of their competence exhibiting path coefficients varying from 0.42 to 0.51. Perception of competence varies with the type of learning environment. An innovative educational format, called 'evidence-based learning (EBL)' is deduced from these findings and described here. Effects of formalization consist of structuring decision making about implementation of different learning environments or about minimizing variance in teaching or learning. Unintended effects of formalization such as implementation problems and bureaucracy are discussed. Formalized tools for designing medical education are available. Specific instructional designs influence students' learning motivation. Concept maps are suitable for controlling educational quality, thus enabling the paradigm shift in medical education.
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D.L. Davies's paper on 'Normal drinking in recovered alcohol addicts' was published in 1962 (Q.J. Stud. Alcohol, 23, (1962) 94). The 18 commentaries on this report which were published shortly afterwards in the Quarterly Journal of Studies on Alcohol are analysed in terms of the perceived relevance of his findings for clinical practice. This initial and largely negative appraisal of the import of Davies's article is contrasted with later assessments which have seen this study as contributing to a crucial paradigm shift. The question is raised as to whether the concept of paradigm shift can be applied satisfactorily to a field where several different scientific disciplines are defining the nature of the problem, or whether alternatively or in addition the story should be understood in terms of a competition between medicine and psychology for 'ownership' of addiction.
During the past 30 years there has been a tremendous development in electrode technology from bulky (90 mm2) to pin-sized (1.0 mm2) electrodes. Simultaneously, impedance has increased from 110 Ohms to >1 kOhms, which has been termed a "paradigm shift" in lead design. If current is responsible for stimulation, why is its impedance a key factor in saving energy? Further, what mechanism is behind this development based on experimental findings and what conclusion can be drawn from it to optimize electrode size? If it is assumed that there is always a layer of nonexcitable tissue between the electrode surface and excitable myocardium and that the electric field (potential gradient) produced by the electrode at this boundary is reaching threshold level, then a formula can be derived for the voltage threshold that completely describes the electrophysiology and electrophysics of a hemispherical electrode. Assuming that the mean chronic threshold for porous steroid-eluting electrodes is 0.6 V with 0.5-ms pulse duration, thickness of nonexcitable tissue can be estimated to be 1.5 mm. Taking into account this measure and the relationship between chronaxie and electrode area, voltage threshold, impedance, and energy as a function of surface area can be calculated. The lowest voltage for 0.5-ms pulse duration is reached with r(o) = 0.5 d, yielding a surface area of 4 mm2 and a voltage threshold of 0.62 V, an impedance of 1 kOhms, and an energy level of 197 nJ. It can be deduced from our findings that a further reduction of surface areas below 1.6 mm2 will not diminish energy threshold substantially, if pulse duration remains at 0.5 ms. Lowest energy is reached with t = chronaxie, yielding an energy level <100 nJ with surface areas < or =1.5 mm2. It is striking to see how well the theoretically derived results correspond to the experimental findings. It is also surprising that the hemispheric model so accurately approximates experimental results with differently shaped electrodes that it can be concluded that electrode shape seems to play a minor role in electrode efficiency. Further energy reduction can only be achieved by reducing the pulse duration to chronaxie. A real paradigm shift will occur only if the fundamentals of electrostimulation in combination with electrophysics are accepted by the pacing community.
The history of science has been described as 'paradigm shifts' of sequential overthrow, each new paradigm replacing the previous one. A paradigm is an overarching view-point which guides the articulation of theories and other activities in a particular field. In the exploration of health, two different types of approach can be identified. The pathogenic view, which has dominated the orientation of medicine over the last hundred years, focuses on disease states and underlying factors that modify the chances of entering into one of those states. The competing salutogenic view appears to be undergoing a renaissance in the new strategies of public health and health promotion, and producing theories of health based on more holistic approaches and diverse methods. The two paradigms exist side by side, and both are in a constant state of flux. The advocates of the health-oriented paradigm say it is difficult to reach a true, in-depth understanding of human health on the basis of a disease-oriented approach or from the traditional vantage-point of risk-factor epidemiology, whereas opponents point out that health does not lend itself to exact measurements or experimentation in keeping with the Galilean natural science ideal. The importance and utility of health orientation need to be explored and ascertained in further research. The approach seems, however, to have a number of crucial assets that might help avoid the limitations of the established disease and risk-factor epidemiology approaches and promote new directions of pursuit, including a better understanding of the complex relationships between aging and health, and other current challenges in creating healthy public policy.
The Internet is an extremely powerful innovation that has and will continue to shape the healthcare industry in the years to come. Albeit a little too slowly, doctors are starting to catch onto this new wave of digital empowerment and creating niches that will enhance their ability to care for their patients and ultimately add value to their practices. The challenge is to encourage every doctor to come on board. The paradigm shift in healthcare delivery is that the Internet brings about the power of information to the patient. This balances the power in the doctor patient relationship. Taken positively, the doctor too can benefit from Internet technology. The biggest contribution of the Internet in the area of electronic medical records is the web-based display environment that is operating-system independent. The Internet can therefore be exploited to provide a supra system that can draw personal medical information together from anywhere to create a virtual electronic medical record. The Internet can also be used to shape up an Internet-based healthcare delivery system. The healthcare delivery paradigm shift brought about by the Internet calls for an eHealth strategy.
Gene-finding methods are classified into homology-based bench-top approach (degenerate cDNA-PCR and cDNA selection), ab initio bench-top approach (cDNA subtraction, two-hybrid system, and exon trapping), homology-based desk-top approach (BLAST search), ab initio desk-top approach (Fgenesh and GENSCAN programs), and hybrid desk-top approach (GenomeScan program). cDNA-library screening, cDNA-PCR, and RACE are used to isolate cDNAs for complete coding sequences. Because WNT signaling molecules are potent targets for oncology, regenerative medicine, and other fields of medical science, we have cloned and characterized many human genes encoding WNT signaling molecules, including 13 out of 19 human WNT genes, and 9 out of 10 human FZD genes. We used degenerate cDNA-PCR and cDNA-library screening in the 20th century, while we use BLAST program and cDNA-PCR in the 21st century. The interval between gene-finding and manuscript-publication in my laboratory was 17.2+/-7.5 (mean +/- SD) months in the 20th century (n=13), 11.5+/-7.8 months in 2001 (n=19), and 5.5+/-1.6 months in 2002 (n=13). The interval using desk-top gene-finding approach (7.2+/-2.6 months, n=30) was significantly shorter than that using bench-top approach (19.8+/-8.0 months, n=15) (p=0.003). Gene-finding has been significantly accelerated due to paradigm shift from bench-top approach to desk-top approach. Dramatic increase of information about human genome, transcriptome and proteome accompanied by improvements of genomics, proteonics and bioinformatics technologies will accelerate paradigm shift from bench-top science to desk-top science.
An inductively coupled plasma (ICP) spectrometer equipped with pneumatic nebulization sample introduction requires mL volumes of sample. For direct elemental analysis of small amounts of solids, an ICP equipped either with a direct sample insertion (DSI) or with an electro-thermal vaporization (ETV) sample introduction system would typically require mg amounts of sample. In my laboratories, we have been developing and characterizing a new sample introduction system we call in-torch vaporization (ITV). The ITV sample introduction system improved significantly the detection limits of ICP spectrometry (both atomic emission and mass spectrometry), thus enabling determinations for micro- and sub-micro size liquid or solid samples. In some cases, even microscopic, nano-size samples were successfully analyzed. In the first part of this paper, development of ITV-ICP for both Atomic Emission Spectrometry (AES) and Mass Spectrometry (MS) will be described. It will be shown that ITV has the potential to cause a paradigm shift in classical elemental analysis by ICP spectrometry by taking analysts from the milli-size (e.g., mg or mL) to the micro-size (e.g., microgram of microL), sub-micro and even nano-sample size-regime. Despite the success of ITV with tiny amounts of sample, such samples must still be collected in the field and must be brought to the laboratory (albeit in smaller containers) for elemental analysis by ICP spectrometry. Would it not be ideal if we could bring an ICP spectrometer to the sample, thus obtaining analytical results in the field (i.e., on-site) and in (near) real-time? Since the typical ICP spectrometer is bulky and heavy and has kWatt power requirements, it is nearly always tethered to a wall socket and it is not usually taken out to the field. Do we need such a large instrument to analyze such tiny samples? In the second part of this paper, current research in my laboratories toward the conceptual goal of miniaturizing elemental analysis instrumentation will be presented. For this, development and characterization of a portable, battery-operated instrument for (near) real-time Hg determination in the field from gases and from liquid and solid micro-samples will be used as an example. Future portable elemental analysis micro-instruments that can be taken out of the lab and into the field are poised to cause another paradigm shift in classical elemental analysis by allowing analysts to bring (part of) the lab to the sample.
An important paradigm (or worldview) shift is occurring in science that affects the nature of nursing education, practice, and research. The shift from positivism to postmodernism and now to neomodernism has received little attention in US nursing and as such may forestall many opportunities related to such change. The nature of this paradigm shift and its effects on selected aspects of nursing education, practice, and research are described, and related implications, problems, and possibilities are explored. Neomodernism is discussed as one future for nursing that encompasses aspects of both positivism and postmodernism but yet goes beyond these to include important metanarratives as traditional values and beliefs of nursing. The work of Laudan and Lakatos are explored as supportive of this neomodernist approach.
This paper presents a shift in the paradigm for treating dental caries from a surgical to a medical approach. Two key points are essential to understanding caries. First, caries is a bacterial infection caused by specific bacteria. Second, before cavitation, caries is a reversible multifactoral process. Two features, caries activity and caries risk, provide a diagnosis and prognosis leading to a treatment plan. Patients receive treatment using a medical model consisting of four steps: bacterial control; reduction of risk levels for at-risk patients; reversal of active sites by remineralization; and follow-up and maintenance.
Whether we practice laboratory medicine in a physician office laboratory or a university hospital laboratory, we find ourselves in the midst of the new focus on total quality, that of quality management of systems. For many decades, manufacturing has placed an emphasis on not just quality control of a process but quality as an expected outcome of their system. Now is the time for laboratory professionals to focus on the future by beginning to develop systems thinking and pursue quality as an outcome. We may not realize it, but we are in the midst of a shift in our Paradigm of Quality. In his book, From Quality to Business Excellence, Charles G. Cobb, states: "The organization, like the human body, is a system; to make it healthy you must consider the whole as well as the parts. That requires looking at the 'system' from a broad cross-functional perspective, just as in a medical analogy, a general practitioner provides an overall view and integrates a team of other specialists as needed".
This review summarizes clinical experience with infectious disease vaccines and data from animal tumor models that support a paradigm shift for cancer vaccines from therapeutic to prevention applications.