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Although the prognostic value of myocardial perfusion imaging is now well established, new data have continued to expand its role in the management of patients. This review addresses the current state-of-the-art and new developments in the use of myocardial perfusion imaging for determining cardiac risk and integrating such information into patient care.
The 21 words that form the basis for this article were selected because they convey the art and science of perianesthesia nursing practice, place perianesthesia nursing in both a national and global context, and facilitate reflection about this specialty practice. Reflection can lead to affirmation or change and perhaps even a design for the future.
This study presents an overview of the state of the art in using molecular dynamics methods to simulate protein folding and in the end game of protein structure prediction. In principle, these methods should allow the highest level of detail possible and the highest accuracy, but they are limited by both the accuracy of the force field used in the simulation and the sampling possible in the available computer time. We describe current capabilities in running the simulations longer and more efficiently.
A meeting entitled "Chromatin Structure and Dynamics: State-of-the-Art" organized by Jordanka Zlatanova and Sanford Leuba was held at the NIH from May 8-10, 2002. It was a timely meeting and addressed our current understanding of chromatin structure, dynamics, and function.
Embryo implantation is a multifactorial event. Biochemical factors are implicated in the quality of the endometrium and in its vascularization. The non-invasive vaginal scan studies the endometrial morphology whereas color and power Doppler studies its vascularity. Through an analysis of the literature, we point out the interest of those techniques in ART.
Chemistry plays a fundamental role in the preservation of our heritage. Artistic and archaeological materials deteriorate over time due to their interaction with the environment, and human intervention can trigger unexpected deterioration pathways. Previous intervention can also sometimes obscure information regarding the original techniques or the materials used to execute the artwork. Our studies of past intervention and attempts to conserve the lunette of the church of Santa Maria la Vetere in Militello Val di Catania (Italy) and Donatello's carved marble panels of the pulpit of the Duomo of Prato (Italy) are discussed as two examples of how chemistry can provide guidance for conservators and fill gaps in the known life of works of art.
This Account presents a comparison between highly precise thermochemical data, including ionization energies, 0 K dissociative photoionization thresholds, and 0 K bond dissociation energies, of selected radicals and molecules and their cations obtained by pulsed field ionization photoion-photoelectron measurements and state-of-the-art thermochemical predictions calculated by the wavefunction-based ab initio CCSD(T)/CBS procedures with high-level corrections. The CCSD(T)/CBS method combines the coupled cluster approach including single, double, and quasi-perturbative triple excitations [CCSD(T)] and the complete basis set (CBS) extrapolation approximation. This benchmarking effort indicates that the CCSD(T)/CBS procedures together with high-level corrections are capable of yielding reliable thermochemical predictions with error limits < or =10 meV for small radicals and molecules and their cations. The error limits increase to approximately 35 meV for larger molecular species, such as phenyl and benzyl radicals.
The LHASA rules for finding strategic bonds in polycyclic target structures are analyzed with respect to the following question: Do the strategic bonds tend to give the greatest simplification upon disconnection, as measured by recently introduced indices of molecular complexity? The answer is yes, at least for the more general rules. This result implies that the bonds most useful for retrosynthetic disconnection can now be identified by a simple calculation rather than by application of a body of rules. It is concluded that organic synthesis, as far as described by these rules, has a mathematical basis and consequently can be considered a science as well as an art.
A state-of-the-art chamber facility is described for investigation of atmospheric aerosol chemistry. Dual 28 m3 FEP Teflon film chambers are used to simulate atmospheric conditions in which aerosol formation may occur. This facility provides the flexibility to investigate dark, single oxidant reactions as well as full photochemical simulations. This paper discusses the environmental control implemented as well as the gas-phase and aerosol-phase instrumentation used to monitor atmospheric aerosol formation and growth. Physical processes occurring in the chamber and procedures for estimating secondary organic aerosol formation during reaction are described. Aerosol formation and evolution protocols at varying relative humidity conditions are presented.
Current trends observed in air pollution control technology are closely related to the development of new, more efficient hybrid systems, i.e., those, which simultaneously utilize two or more physical mechanisms for dust or gaseous contaminants removal. These systems can operate more economically than conventional devices, especially in the removal of PM2.5 particles. The electrostatic scrubber (electroscrubber), discussed in this paper, is one of such types of devices, which combines advantages of electrostatic precipitators and inertial wet scrubbers, and removes many shortcomings inherent to both of these systems operating independently. The electroscrubber is a device in which Coulomb attraction or repulsion forces between electrically charged scrubbing droplets (collector) and dust particles are utilized for the removal of particles from a gas. Unlike wet electrostatic precipitators in which particles are precipitated only on the collection electrode, in electroscrubbers, the collection of dust particles takes place in the entire precipitator chamber. Compared to inertial scrubbers, the electroscrubbers can operate at lower droplet velocities, but the collection efficiency for a single droplet can be larger than 1. The paper reviews the state-of-the-art of wet electrostatic scrubbing (electroscrubbing) technique used for gas cleaning from dust or smoke particles. Three groups of problems are discussed: (1) The fundamental problems concerning the charged dust particle deposition on a charged collector, usually a drop, with a focus on different models describing the process. (2) The experimental works of fundamental importance to our knowledge referring to the scrubbing process, which can be used for validating the theory. (3) The laboratory demonstrations and industrial tests of different constructions of electroscrubbers designed for effective gas cleaning. The electroscrubber is not designed to replace wet or dry electrostatic precipitators but can be used as a complementary device following the last stage of conventional electrostatic precipitator, which helps to remove submicron particles. It was shown in the paper that a higher collection efficiency of an electroscrubber could be obtained for higher values of Coulomb number (i.e., higher electric charges on the collector and particle), and for a Stokes number lower than5 (i.e., low particle-collector relative velocity).
For more than three centuries we have relied on the extracts of the bark of Cinchona species to treat malaria. Now, it seems we may be changing to the leaves of a Chinese weed, Artemisia annua, and its active compound artemisinin. Artemisinin-derived drugs have been proved particularly effective treatments for severe malaria, even for multidrug-resistant malaria. However, this promising antimalarial compound remains expensive and is hardly available on a global scale. Therefore, many research groups have directed their investigations toward the enhancement of artemisinin production in A. annua cell cultures or whole plants in order to overproduce artemisinin or one of its precursors. This article provides a brief review of the state of art of the different aspects in A. annua research.
OBJECTIVES: This study measured the impact of an educational intervention aimed at heightening rural physicians' awareness of state-of-the-art breast and colorectal cancer therapies. METHODS: Pre- and post-intervention mailed surveys were administered to all primary-care physicians and referring physicians in the seven-county intervention region in North Carolina (NC) and a comparison region in South Carolina (SC). RESULTS: The survey revealed few significant changes in physicians' perspectives that could be attributed to the intervention. Physicians erroneously stated that lumpectomy without follow-up radiation was acceptable for treating breast cancer (55%), failed to indicate that adjuvant therapy was an accepted practice for treating Stage I breast cancer (67%), failed to acknowledge chemotherapy as experimental for Dukes' B colon cancer patients (70%), and failed to recognize a combination of surgery, chemotherapy, and radiation as a standard treatment for rectal cancer (25%). CONCLUSIONS: The low levels of awareness of National Cancer Institute guidelines were reflected in low breast-sparing surgery rates for women living in the intervention region. Stronger consensus on appropriate cancer treatments is needed throughout the medical community in order to reduce undesired variation in rural, community-based cancer care.
Perceptions are often merely regarded as the basic elements of knowledge. They have, however, a complex structure of their own and are far from being elementary. My paper will analyze two basic patterns of perception and some of the resulting medical implications. Most basically, all object perception is characterized by a mixture of knowledge and ignorance (Husserl). Perception essentially perceives with inner and outer horizons, brought about by the kinesthetic activity of the perceiving subject (Sartre). This first layer of perceptual reality, the world of "open" perceptions, is the inescapable background for "every rationality, every value, every existence" (Merleau-Ponty). On an epistemological level a characteristic change of perceptual patterns in medicine was introduced by pathological anatomy (Foucault). The reference of medical perception to the dead body created the new possibility of "absolute" perception, allowing for more precise medical interventions, but at the same time coming into conflict with the open structures of "ordinary," non-scientific perception patterns in everyday life. On the basis of these distinctions, an analysis of the different perceptual patterns in medicine becomes possible. Such an analysis would be the task of a sub-field in medical philosophy that could be called "medical aesthetics" having as its goal an "art of perception" understood as a technique of adequately applying different perceptual patterns in medical practice.
Seagrave and Grisso (2001) questioned the clinical-forensic utility of tests designed to assess juvenile psychopathy. They discussed potential problems with such tests and some avenues for future research. We agree with the points made by Seagrave and Grisso, but believe their critique did not go far enough. The "state of the art" with respect to the assessment of juvenile psychopathy is like an Impressionist painting: fine from a distance; but the closer you get, the messier it looks. We conclude that although tests of "juvenile psychopathy" measure something, it is impossible to be sure at this time they are actually measuring psychopathy.
The relationship between evidence-based medicine (EBM) and clinical judgement is the subject of conceptual and practical dispute. For example, EBM and clinical guidelines are seen to increasingly dominate medical decision-making at the expense of other, human elements, and to threaten the art of medicine. Clinical wisdom always remains open to question. We want to know why particular beliefs are held, and the epistemological status of claims based in wisdom or experience. The paper critically appraises a number of claims and distinctions, and attempts to clarify the connections between EBM, clinical experience and judgement, and the objective and evaluative categories of medicine. I conclude that to demystify clinical wisdom is not to devalue it. EBM ought not be conceived as needing to be limited or balanced by clinical wisdom, since if its language is translatable into terms comprehensible and applicable to individuals, it helps constitute clinical wisdom. Failure to appreciate this constitutive relation will help perpetuate medical paternalism and delay the adoption of properly evidence-based practice, which would be both unethical and unwise.
The concept of the art of healing is intrinsically connected with the idea of healing powers. There are at least three possible approaches to that idea and all of them have different implications for the problem of medical wisdom. These are: the idea of the healing powers of nature, the idea of the healing powers of science, and the idea of the healing powers of physician's personality. Having critically discussed those ideas I sketch an ideal of a wise physician as someone who has a particular kind of knowledge, good judgement, and self-trust. Medical knowledge is certainly a necessary condition of being a wise doctor but it is not the sufficient one. And this is why patients generally prefer to seek help of "naturally wise physicians".
It is just over a century since successful brain tumor resection. Since then the diagnosis, imaging, and management of brain tumors have improved, in large part due to technological advances. Similarly, the operating room (OR) for brain tumor surgery has increased in complexity and specificity with multiple forms of equipment now considered necessary as technical adjuncts. It is evident that the theme of minimalism in combination with advanced image-guidance techniques and a cohort of sophisticated technologies (e.g., robotics and nanotechnology) will drive changes in the current OR environment for the foreseeable future. In this report we describe what may be regarded today as standard essentials in an operating room for the surgical management of brain tumors and what we believe to be the current 'state-of-the-art' brain tumor OR. Also, we speculate on the additional capabilities of the brain tumor OR of the near future.
OBJECTIVES: To study macrosomatognosia and microsomatognosia occurring as migraine aura symptoms. MATERIAL AND METHODS: Topological distribution of these body schema disturbances were assessed in a collection of 562 pictures submitted as entries to the 4 national Migraine Art competitions. RESULTS: The said symptoms were illustrated by 18 artists. Macrosomatognosia was encountered more frequently than microsomatognosia and applied more often to single parts of the body, whereas microsomatognosia mostly affected the entire body. In partial macrosomatognosia, the head and upper extremities were the body parts most frequently involved, paralleling the extension of their representation in the sensory maps of the human brain. CONCLUSIONS: The conscious perceptual experiences of whole body macro- and microsomatognosia argue in favour of the existence of an integrative neuronal network mediating whole body perception. Partial macro- and microsomatognosia suggest a reversible modification of cerebral maps of somatosensation during the migraine aura.