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PubMed1996

[What are affects?].

In an attempt to answer the question, "what is affect?", this paper considers Freud's metapsychological formulation in the light of recent developments in psychoanalysis and neuroscience. It argues that the problem of affect-perhaps more than any other-forces us to acknowledge the intrinsic connexion between mind and body, and to accommodate it in our theoretical formulations. A review of the problem from this point of view leads to the following formulation: affect is a primary sensory modality, analogous to the senses of vision, hearing, somatic sensation, taste, and smell. These modalities are the elementary constituents of the envelope of consciousness, from which it is impossible to free ourselves. Whereas the sensory modalities of vision, hearing, somatic sensation, taste, and smell represent aspects of the external object world ("unknowable" in itself), affect is the primary sensory modality through which we perceive as aspect of the internal world of the subject ("unconscious" in itself).

Affect↗

PubMed2005

Detecting and aligning peaks in mass spectrometry data with applications to MALDI.

In this paper, we address the peak detection and alignment problem in the analysis of mass spectrometry data. To deal with the peak redundancy problem existing in the MALDI data acquired in the reflectron mode, we propose to use the amplitude modulation technique in peak detection. The alignment of two peak sets is formulated as a non-rigid registration problem and is solved using a robust point matching (RPM) approach. To align multiple peak sets, we first use a super set method to find a common peak set among all peak sets as a standard and then align all peak sets to the standard using the robust point matching approach in a sequential manner (i.e. We align only one peak set to the standard each time, thus reducing the multiple peak set alignment problem to a simpler two peak set alignment problem). Experimental results from a study of ovarian cancer data set show that the quantitative cross-correlation coefficients among technical replicates are increased after peak alignment. Additional comparisons also demonstrate that our method has a similar performance as the hierarchical clustering method, although the implementations of these methods are different.

Female↗

PubMed1993

[The education of neurologists for the XXI century].

The training of neurologists for the practice in the coming years requires deep changes in the system of medical education. It is critical for the medical student and the resident the acquisition of a broad knowledge of scientific information. But physicians must also know how to use knowledge they have accumulated from a variety of sources. They express their knowledge through abilities in the wards or in ambulatory settings in order to get an accurate diagnosis and the proper management of a particular condition. In addition to that they are expected to develop ethical attitudes toward their patients, peers and the greater society. They must be committed to work, to independent learning and to rationality. To accomplish its scholarly goals medical education has to emphasize the development of adequate personal attributes, skills and habits of mind rather than the transmission of factual information. With today's technology all the scientific information necessary for the practice of medicine is at the fingertips through computers. Memorization is therefore an absolute nonsense in teaching. A better education involves reducing the working load and the number of lecture hours providing students and residents with sufficient unscheduled time to seek out information independently and to assess their own learning. Problem-solving methods of teaching providing the formulation of multiple concurrent hypotheses, the critical analysis and evaluation of data and the application of new acquired knowledge as well as previously learned concepts to the solution of problems should be widely employed. Faculty members are guides who assist students and residents to develop analytical and critical skills.(ABSTRACT TRUNCATED AT 250 WORDS)

Education, Medical↗

PubMed2003

Health education for nurses in Japan to combat child abuse.

A health education program for nurses was conducted to address the complex problem of child abuse, which has reached epidemic proportions. In Japan, the number of consultations has risen 23-fold over the past 11 years. Maltreatment of children is a public health problem as perilous as any contagious disease. The International Council of Nurses asks for nurses' leadership to strengthen measures to combat abuse throughout the world. The Japanese Nursing Association has published statements for prevention, detection and support. Yet, few community-based education programs with a multidisciplinary perspective have been reported that focus on nurses, the largest group of health providers. More than 200 nurse educators, clinicians and managers met for a one-day program designed to improve understanding of the nurses' role in combatting the abuse and neglect of children and to formulate action plans. This significant health problem is addressed in the context of a health education program's needs, objectives, content and evaluation.

Child↗

PubMed2001

Protein Crystals as Novel Catalytic Materials.

In this era of molecular biology, protein crystallization is often considered to be a necessary first step in obtaining structural information through X-ray diffraction analysis. In a different light, protein crystals can also be thought of as materials, whose chemical and physical properties make them broadly attractive and useful across a larger spectrum of disciplines. The full potential of these protein crystalline materials has been severely restricted in practice, however, both by their inherent fragility, and by strongly held skepticism concerning their routine and predictable growth, formulation, and practical application. Fortunately, these problems have turned out to be solvable. A systematic exploration of the biophysics and biochemistry of protein crystallization has shown that one can dependably create new protein crystalline materials more or less at will. In turn, these crystals can be readily strengthened, both chemically and mechanically, to make them suitable for practical commercialization. Today, these novel materials are used as industrial catalysts on a commercial scale, in bioremediation and "green chemistry" applications, and in enantioselective chromatography of pharmaceuticals and fine chemicals. In the near future, their utility will expand, to include the purification of protein drugs, formulation of direct protein therapeutics, and development of adjuvant-less vaccines.

Journal Article↗

PubMed2001

Initial theoretical framework and problem solving concerning the enigma of heredity.

The difference in formulation of the question of heredity on a different level of knowledge in Brno in the 1830s and after 1850 is discussed in this article. In order to solve the problem the most important source is foreshown in the new philosophy of plant physiology and in physics. Mendel was pleased to have met excellent teachers of both these fields. This explanation is an example of Mirko Grmek's thesis: 'l'histoire des sciences est le laboratoire de l'épistomologie'.

Animals↗

PubMed2003

[Biomedical support to a piloted Martian expedition].

Review of the main problems of biomedical support (BMS) to a piloted mission to Mars has revealed a correlation of the BMS constituents and parameters with the specifics of this venture that makes it significantly different from the near-Earth flights. Success of the transit to Mars and back and safety of the planet explorers will hinge on the BMS system functionality in the harsh changing environment and power to ensure medical safety, health and performance of the crew. Particular emphasis has been placed on the necessity to enhance methods of crew selection and training, to develop an on-board medical center including an appropriate database, to search for high-efficiency countermeasures, to formulate prescriptions for resolution possible psychological problems in flight, and to design and manufacture regenerative life support and radiation protection systems.

Astronauts↗

PubMed2004

Preliminary report of the discovery of a new pharmaceutical granulation process using foamed aqueous binders.

Spray granulation is commonly used to improve the flow of drug formulation powders by adding liquid binders. We have discovered a new granulation process whereby liquid binders are added as aqueous foam. Initial experiments indicate that foam granulations require less binder than spray granulations, less water is added to the powder mass, rates of addition of foam can be greater than rates of addition of sprayed liquids, and foam can be added in a single batch to the surface of the powder mass for incorporation at some later stage in the process. This new process appears to have no detrimental effects on granulate, tablet, or in vitro drug dissolution properties. In addition, the elimination of spray addition reduces the complexity of the process and avoids the plugging problems associated with spray nozzles. Several formulations were successfully scaled up from laboratory scale (1.5 kg) to pilot scale (15 kg). Process control was good and there was no detrimental effect on tablet and drug dissolution properties. This paper also proposes a working hypothesis of the mechanism by which foam granulation operates.

Delayed-Action Preparations↗

PubMed1977

Undergraduate medical education in geriatrics: nursing home experience.

Preclinical medical students undertook an elective course in geriatrics which combined instruction in history taking, physical diagnosis, and problem-oriented assessment of elderly patients in a nursing home. A drug utilization review and specific drug therapy plans were formulated by pharmacy students. The project identified general problems susceptible to institutional as well as individual remedy. The students were led beyond their initial preoccupation with "physical complaints" to interest in pertinent psychological, social, and economic factors. A model of geriatric education for health science students can productively link the health science center and community nursing homes with benefits for the student, the patient, and the nursing home.

Aged↗

PubMed2005

Haruan (Channa striatus) incorporated palm-oil creams : formulation and stability studies.

Topical emulsions stabilized with non-ionic emulsifiers have been an attractive alternative as vehicles for drug delivery, particularly for the patients suffering from dermatological problems. Haruan (a natural wound healer) creams were formulated with different types of emulsifiers (Tween 80 and Span 80) using different grades of Malaysian Palm-oleins (DFPL 56, 60, 62 and 65). The stability (at room temperature and accelerated stability testing) of the various creams was evaluated at different temperatures (5, 25 and 45 degrees C) for a period of 6 months by measuring changes in droplet size, viscosity and percentage oil separation. The emulsifier type and concentration showed pronounced effect on the physicochemical properties of the cream, whereas storage time did not. This study suggested that the choice of emulsifiers and concentration of haruan extract are the most important factors in the stability of the haruan creams.

Animals↗

PubMed2006

Maximum likelihood of phylogenetic networks.

MOTIVATION: Horizontal gene transfer (HGT) is believed to be ubiquitous among bacteria, and plays a major role in their genome diversification as well as their ability to develop resistance to antibiotics. In light of its evolutionary significance and implications for human health, developing accurate and efficient methods for detecting and reconstructing HGT is imperative. RESULTS: In this article we provide a new HGT-oriented likelihood framework for many problems that involve phylogeny-based HGT detection and reconstruction. Beside the formulation of various likelihood criteria, we show that most of these problems are NP-hard, and offer heuristics for efficient and accurate reconstruction of HGT under these criteria. We implemented our heuristics and used them to analyze biological as well as synthetic data. In both cases, our criteria and heuristics exhibited very good performance with respect to identifying the correct number of HGT events as well as inferring their correct location on the species tree. AVAILABILITY: Implementation of the criteria as well as heuristics and hardness proofs are available from the authors upon request. Hardness proofs can also be downloaded at http://www.cs.tau.ac.il/~tamirtul/MLNET/Supp-ML.pdf

Algorithms↗

PubMed2005

Economic evaluation of interventions for problem drinking and alcohol dependence: cost per QALY estimates.

AIMS: To compare the performance of competing and complementary interventions for prevention or treatment of problem drinking and alcohol dependence. To provide an example of how health maximising decision-makers might use performance measures such as cost per quality adjusted life year (QALY) league tables to formulate an optimal package of interventions for problem drinking and alcohol dependence. METHODS: A time-dependent state-transition model was used to estimate QALYs gained per person for each intervention as compared to usual care in the relevant target population. RESULTS: Cost per QALY estimates for each of the interventions fall below any putative funding threshold for developed economies. Interventions for problem drinkers appear to offer better value than interventions targeted at those with a history of severe physical dependence. CONCLUSIONS: Formularies such as Australia's Medicare should include a comprehensive package of interventions for problem drinking and alcohol dependence.

Adolescent↗

PubMed2005

First-order system least-squares (FOSLS) for modeling blood flow.

The modeling of blood flow through a compliant vessel requires solving a system of coupled nonlinear partial differential equations (PDEs). Traditional methods for solving the system of PDEs do not scale optimally, i.e., doubling the discrete problem size results in a computational time increase of more than a factor of 2. However, the development of multigrid algorithms and, more recently, the first-order system least-squares (FOSLS) finite-element formulation has enabled optimal computational scalability for an ever increasing set of problems. Previous work has demonstrated, and in some cases proved, optimal computational scalability in solving Stokes, Navier-Stokes, elasticity, and elliptic grid generation problems separately. Additionally, coupled fluid-elastic systems have been solved in an optimal manner in 2D for some geometries. This paper presents a FOSLS approach for solving a 3D model of blood flow in a compliant vessel. Blood is modeled as a Newtonian fluid, and the vessel wall is modeled as a linear elastic material of finite thickness. The approach is demonstrated on three different geometries, and optimal scalability is shown to occur over a range of problem sizes. The FOSLS formulation has other benefits, including that the functional is a sharp, a posteriori error measure.

Algorithms↗

PubMedDate not supplied

Comprehensive diagnosis: a conceptual basis for future diagnostic systems.

A discussion of the objectives of diagnosis, participants and architecture leads to the consideration of diagnostic schemas of increasing complexity. Examined first is the conventional case of single-label diagnosis. The case of multiple illness formulation is considered concerning the plurality of mental disorders as well as of general medical disorders. The formulation of a whole clinical condition where contextualized pathology and problems are described is then followed by the consideration of positive aspects of health as well as quality of life. Finally, a comprehensive diagnostic model is reviewed. It integrates a standardized multiaxial formulation (illness, disabilities, contextual factors and quality of life) and an idiographic personalized formulation (culturally informed and contextualized clinical problems, patient's assets pertinent to care, and expectations of health restoration and promotion as jointly understood by clinician, patient and family). Such integrative diagnostic schemas may offer a richer informational basis for clinical description and care as well as a more effective focus for the surveillance of population health.

Comorbidity↗

PubMed1999

Eutectic colony formation: a stability analysis.

Experiments have widely shown that a steady-state lamellar eutectic solidification front is destabilized on a scale much larger than the lamellar spacing by the rejection of a dilute ternary impurity and forms two-phase cells commonly referred to as "eutectic colonies." We extend the stability analysis of Datye and Langer [V. Datye and J. S. Langer, Phys. Rev. B 24, 4155 (1981)] for a binary eutectic to include the effect of a ternary impurity. We find that the expressions for the critical onset velocity and morphological instability wavelength are analogous to those for the classic Mullins-Sekerka instability of a monophase planar interface, albeit with an effective surface tension that depends on the geometry of the lamellar interface and, nontrivially, on interlamellar diffusion. A qualitatively new aspect of this instability is the occurrence of oscillatory modes due to the interplay between the destabilizing effect of the ternary impurity and the dynamical feedback of the local change in lamellar spacing on the front motion. In a transient regime, these modes lead to the formation of large scale oscillatory microstructures for which there is recent experimental evidence in a transparent organic system. Moreover, it is shown that the eutectic front dynamics on a scale larger than the lamellar spacing can be formulated as an effective monophase interface free boundary problem with a modified Gibbs-Thomson condition that is coupled to a slow evolution equation for the lamellar spacing. This formulation provides additional physical insights into the nature of the instability and a simple means to calculate an approximate stability spectrum. Finally, we investigate the influence of the ternary impurity on a short wavelength oscillatory instability that is already present at off-eutectic compositions in binary eutectics.

Journal Article↗

PubMed2006

Multiobjective optimization of an ultrasonic transducer using NIMBUS.

The optimal design of an ultrasonic transducer is a multiobjective optimization problem since the final outcome needs to satisfy several conflicting criteria. Simulation tools are often used to avoid expensive and time-consuming experiments, but even simulations may be inefficient and lead to inadequate results if they are based only on trial and error. In this work, the interactive multiobjective optimization method NIMBUS is applied in designing a high-power ultrasonic transducer. The performance of the transducer is simulated with a finite element model, and three design goals are formulated as objective functions to be minimized. To find an appropriate compromise solution, additional preference information is needed from a decision maker, who in our case is an expert in transducer design. A realistic design problem is formulated, and an interactive solution process is described. Our findings demonstrate that interactive multiobjective optimization methods, combined with numerical simulation models, can efficiently help in finding new solution approaches and possibilities as well as new understanding of real-life problems as entirenesses. In this case, the decision maker found a solution that was better with respect to all three objectives than the conventional unoptimized design.

Journal Article↗

PubMed1978

The relation of product formulation to absorption of oral theophylline.

To assess the potential for therapeutic problems related to the bioavailability of oral theophylline preparations, we examined the rate and extent of absorption for various formulations in adult volunteers. Absorption of theophylline from a solution or from uncoated tablets was rapid and complete. Three of six sustained-release formulations were more slowly, but still completely and consistently, absorbed. Absorption of the other three sustained-release formulations appeared to be more erratic and less complete. Serum concentration-time curves during multiple eight-hour dosing were simulated for the bioavailable preparations. With three sustained-release formulations it was predicted that fluctuations in serum theophylline concentrations between doses would decrease, as compared with uncoated tablets, to a clinically important extent, particularly in children, in whom elimination of theophylline is generally rapid.

Administration, Oral↗

PubMed2000

Current status of immunization against anthrax: old vaccines may be here to stay for a while.

Anthrax vaccination has become a 'hot' topic. On the one hand, fears that Iraq holds secret caches of anthrax-based weaponry, that other countries may be developing or may have developed similar devices, or that hard-line groups may make their own anthrax-based devices for bioterrorist attacks have focused official attention on the need for means of protection, principally, though, for the military. On the other hand, the unsolved issues of the Gulf War illnesses have left elements of doubt in the minds of some as to the possible role of anthrax (among other) vaccines in this syndrome, and have drawn attention to the shortage of pre-clinical, clinical, pharmacological and safety data on the existing UK and US anthrax vaccines. In the middle are those hotly debating the US and Canadian policies of mandatory anthrax immunization for military personnel or, in the case of the UK policy of voluntary immunization, simply voting with their feet. Compounding matters have been the publicized failures of the US vaccine production facility and the less publicized UK problems of supply. Meanwhile, those in genuine at-risk occupations are left unsure whether, if they can get the vaccine at all, they really want it. Despite two decades of elegant science aimed at formulating alternative vaccines to overcome all the problems of efficacy, safety and supply, such an alternative is at least five years away, and the current status is that we must live with the old vaccines or not vaccinate.

Journal Article↗