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PubMed2005

Exploring the benefits of an exercise program for people with schizophrenia: a qualitative study.

The relationship between regular exercise and physical health and well-being is extensively documented in the literature. However, considerably less attention is devoted to the impact of exercise on health outcomes for people experiencing a mental illness. In response to the recognized paucity, a structured exercise program was developed and implemented for residents of a Community Care Unit in metropolitan Melbourne, Australia. Six residents participated in the program over a period of three months. This paper reports the findings of a qualitative study. A focus group interview was conducted with the resident participants (n=6), the exercise physiologists who developed and implemented the program (n=2), and nursing staff involved in implementing and supporting the program (n=4). Analysis of the data collected revealed that four main themes had emerged: the individual nature of the program, physical improvement, group dynamics, and future plans. The findings of this study suggest that involvement in the program produced very positive outcomes, most notably in the physical fitness of residents. The individual nature of the program which enabled gradual participation, and the cohesive approach of the group as a whole were considered very important factors contributing to the overall success. Furthermore, the participants planned to continue with some form of physical activity in the future. The potential value of regular exercise for patients experiencing a mental illness has significant implications for nursing and requires further research exploration.

Adult↗
PubMedDate not supplied

[Algorithms and computation methods of diagnostic coefficients in dynamic scintigraphy of skeleton and skeletal muscles].

The paper is concerned with a program for data processing of dynamic scintigraphy of the skeleton and skeletal muscles using 99mTc-sodium 1-hydroxy-ethane-1, 1-diphosphonate. Employing gamma-chamber computer the program enables rapid and precise computation of the coefficient of RP elimination from the blood and the coefficients of RP accumulation by the bones and muscle tissue. Based on those coefficients one can make diagnosis and follow the time-course of pathological changes occurring in the skeleton during endocrine diseases.

Algorithms↗
PubMed2003

Dimension change, coarse grained coding and pattern recognition in spatio-temporal nonlinear systems.

Several research programs employing spatio-temporal recurrent dynamics and changes in dimensionality have extended the dialog on neural computation and coding beyond classical frameworks such as feed forward and attractor neural networks and feature detectors. Some have emphasized spiking networks, while others emphasize oscillations and synchronization as the locus of computation and coding. In this paper, the formalism of locally connected homogeneous coupled map lattices is described. Its deployment in an extended version of the dynamical recognizer framework is described, and is compared with density coding, computational mechanics, and liquid state machine frameworks for neural computation. A population coding strategy based on coarse graining the continuous valued distribution of all sites in the lattice is developed and examined as a form of dimension reduction. Results on recognition of 3-D objects are reported. In order to better understand the dynamics supporting recognition, measures suggested by these other research programs and computational frameworks were examined. Dynamics trajectories from object recognition trials were examined for correlation with recognition rates and measures of the distance of the representation space statistics between the target objects and noise initial conditions, and the intrinsic separation between different objects in the set to be classified were performed. These results raise questions about the efficacy of density coding as an explanation for the results, and on the validity of recent criticisms that chaotic systems cannot satisfy separation requirements required for real time computation.

Artifacts↗
PubMed2005

Enhancing dynamic graphical analysis with the Lisp-Stat language and the ViSta statistical program.

Presented is a sample of computerized methods aimed at multidimensional scaling and psychometric item analysis that offer a dynamic graphical interface to execute analyses and help visualize the results. These methods show how the Lisp-Stat programming language and the ViSta statistical program can be jointly applied to develop powerful computer applications that enhance dynamic graphical analysis methods. The feasibility of this combined strategy relies on two main features: (1) The programming architecture of ViSta enables users to add new statistical methods as plug-ins, which are integrated into the program environment and can make use of all the functions already available in ViSta (e.g., data manipulation, editing, printing); and (2) the set of powerful statistical and graphical functions integrated into the Lisp-Stat programming language provides the means for developing statistical methods with dynamic graphical visualizations, which can be implemented as ViSta plug-ins.

Computer Graphics↗
PubMed2001

Complex species interactions and the dynamics of ecological systems: long-term experiments.

Studies that combine experimental manipulations with long-term data collection reveal elaborate interactions among species that affect the structure and dynamics of ecosystems. Research programs in U.S. desert shrubland and pinyon-juniper woodland have shown that (i) complex dynamics of species populations reflect interactions with other organisms and fluctuating climate; (ii) genotype x environment interactions affect responses of species to environmental change; (iii) herbivore-resistance traits of dominant plant species and impacts of "keystone" animal species cascade through the system to affect many organisms and ecosystem processes; and (iv) some environmental perturbations can cause wholesale reorganization of ecosystems because they exceed the ecological tolerances of dominant or keystone species, whereas other changes may be buffered because of the compensatory dynamics of complementary species.

Animals↗
PubMedDate not supplied

Immunization education among family practice residency programs.

BACKGROUND AND OBJECTIVES: The dynamic nature of immunization schedules, shortages, and administration techniques makes keeping up to date with current national recommendations difficult and necessitates periodic evaluation of immunization teaching resources. METHODS: This study surveyed family practice residency program directors in 1998 to assess their satisfaction with immunization teaching resources and interest in new resources. Subsequently, with funding from the Centers for Disease Control and Prevention, the Society of Teachers of Family Medicine Group on Immunization Education developed a series of educational materials devoted to educating family physicians about immunizations. In 2001, residency directors were surveyed again to evaluate the educational resources. RESULTS: Most program directors reported satisfaction with resources currently available to them for teaching residents about childhood immunizations, but about half (41% in 1998 versus 55% in 2001) agreed that keeping up to date on childhood immunizations was difficult. The corresponding figures for adult immunizations were 27% in 1998 and 36% in 2001. Pocket-size immunization schedules were ranked highly important (53% in 1998 versus 45% in 2001). Many would use handheld computer immunization schedules (53%). Although satisfaction with available resources did not increase following introduction of a newly developed journal supplement and Web site, the limited response received was favorable. CONCLUSIONS: Immunization teaching materials developed by family physicians, especially those that make use of evolving technologies, can be useful resources for individuals teaching family practice residents and for keeping up to date on recommendations for immunizations.

Family Practice↗
PubMed2001

The portable UNIX programming system (PUPS) and CANTOR: a computational environment for dynamical representation and analysis of complex neurobiological data.

Many problems in analytical biology, such as the classification of organisms, the modelling of macromolecules, or the structural analysis of metabolic or neural networks, involve complex relational data. Here, we describe a software environment, the portable UNIX programming system (PUPS), which has been developed to allow efficient computational representation and analysis of such data. The system can also be used as a general development tool for database and classification applications. As the complexity of analytical biology problems may lead to computation times of several days or weeks even on powerful computer hardware, the PUPS environment gives support for persistent computations by providing mechanisms for dynamic interaction and homeostatic protection of processes. Biological objects and their interrelations are also represented in a homeostatic way in PUPS. Object relationships are maintained and updated by the objects themselves, thus providing a flexible, scalable and current data representation. Based on the PUPS environment, we have developed an optimization package, CANTOR, which can be applied to a wide range of relational data and which has been employed in different analyses of neuroanatomical connectivity. The CANTOR package makes use of the PUPS system features by modifying candidate arrangements of objects within the system's database. This restructuring is carried out via optimization algorithms that are based on user-defined cost functions, thus providing flexible and powerful tools for the structural analysis of the database content. The use of stochastic optimization also enables the CANTOR system to deal effectively with incomplete and inconsistent data. Prototypical forms of PUPS and CANTOR have been coded and used successfully in the analysis of anatomical and functional mammalian brain connectivity, involving complex and inconsistent experimental data. In addition, PUPS has been used for solving multivariate engineering optimization problems and to implement the digital identification system (DAISY), a system for the automated classification of biological objects. PUPS is implemented in ANSI-C under the POSIX.1 standard and is to a great extent architecture- and operating-system independent. The software is supported by systems libraries that allow multi-threading (the concurrent processing of several database operations), as well as the distribution of the dynamic data objects and library operations over clusters of computers. These attributes make the system easily scalable, and in principle allow the representation and analysis of arbitrarily large sets of relational data. PUPS and CANTOR are freely distributed (http://www.pups.org.uk) as open-source software under the GNU license agreement.

Algorithms↗
PubMed1994

The integrated dynamic exercise advancement system technique for progressing functional closed kinetic chain rehabilitation programs.

Graded exercise progressions are necessary during the rehabilitation process. We developed the Integrated Dynamic Exercise Advancement System (IDEAS) to fill this void. There appears to be a lack of progression/advancement systems for closed kinetic chain exercises, even though the IDEAS technique for advancing closed chain activities is comprised of two phases: preparing a safe environment and advancing the exercise. Phase one includes a conceptual checklist to assess the safety of the environment. Phase two is a six-step process that challenges each plane of motion by adding speed, workload, external stimuli, and terrain changes. The IDEAS technique is presented to safely prepare an environment and help clinicians to put thought into advancing an exercise program. The IDEAS technique is suggested for use in other arenas such as strength and conditioning.

Journal Article↗
PubMed2004

MoViES: molecular vibrations evaluation server for analysis of fluctuational dynamics of proteins and nucleic acids.

Analysis of vibrational motions and thermal fluctuational dynamics is a widely used approach for studying structural, dynamic and functional properties of proteins and nucleic acids. Development of a freely accessible web server for computation of vibrational and thermal fluctuational dynamics of biomolecules is thus useful for facilitating the relevant studies. We have developed a computer program for computing vibrational normal modes and thermal fluctuational properties of proteins and nucleic acids and applied it in several studies. In our program, vibrational normal modes are computed by using modified AMBER molecular mechanics force fields, and thermal fluctuational properties are computed by means of a self-consistent harmonic approximation method. A web version of our program, MoViES (Molecular Vibrations Evaluation Server), was set up to facilitate the use of our program to study vibrational dynamics of proteins and nucleic acids. This software was tested on selected proteins, which show that the computed normal modes and thermal fluctuational bond disruption probabilities are consistent with experimental findings and other normal mode computations. MoViES can be accessed at http://ang.cz3.nus.edu.sg/cgi-bin/prog/norm.pl.

Computational Biology↗
PubMed2001

Evidence for shared genetic programs from cluster analysis of hippocampal gene expression dynamics in development and response to injury.

Cluster analysis is a computational method that groups together similarly-shaped patterns. It may be applied to large-scale gene expression data to form new hypotheses regarding gene function. In the present study, we clustered the temporal expression patterns of genes expressed in the rat hippocampus during normal development and after a kainate-induced seizure injury at postnatal day 25. We found that two different methods, Euclidean hierarchical and K-means clustering, produced slightly different results, and concluded that different clustering methods may he used to complement one another. We also found that certain genes cluster together both during development and after seizure injury, consistent with the idea of sets of genes that act in concert under various conditions.

Animals↗
PubMed2004

[Scintigraphic assessment of the anorectal function in children with idiopathic constipation].

OBJECTIVE: The ability of the rectum to evacuate is valuable information in patients with constipation, or those who find defecation difficult. However, few published studies are available to evaluate this ability in most common examinations of anorectal function. A new, low-radiation, real-time scintigraphic technique has been used by several investigators to outline the 'neo-rectum' following ileoanal pouch anastomosis and the efficiency of rectal evacuation in adult patients with constipation. There was no similar report about the abilities of rectal evacuation in children with constipation. The aim of this study was to investigate the value and reliability of isotope defecography as an objective method for evaluation of anorectal function in patients with chronic idiopathic constipation. METHODS: Twenty five patients (10 were male and 15 were female, range of age was 5 - 15 years, mean age 8.99 years) suffering from chronic idiopathic constipation and 11 normal children were assessed by isotope defecography. The radiopharmaceuticals used were rehydrated potato labelled with 200 MBq (99m)TcO(4)(-). The volume of the potato paste used in each subject was determined by prior balloon proctometrogram studies, which measured the maximum rectal capacity. The patient was seated upright on a commode, and the computer was then set for the dynamic acquisition of 3-second images over 5 min per session. Using a region of interest program on computer, the dynamic radioactivity in anorectum during defecation showed as emptying curves by computer. The half defecation time, the rectal emptying rate and the residual rate could be calculated from the rectal emptying curves. The anorectal angles were measured from the images of anorectum during resting, squeezing and evacuation. All patients underwent X-ray defecography and colonic transit time measurement simultaneously. RESULTS: The rectal emptying curves showed a prompt evacuation in normal children, but it disappeared in most of patients with idiopathic constipation. The abilities of evacuation were damaged severely in patients. In normal group the half defecation time, the rectal emptying rate and the residual rate were 1.97 +/- 0.86 minutes, 78.30% +/- 12.03% and 20.50% +/- 7.67%, respectively, whereas they were 15.16 +/- 3.67 minutes, 44.84% +/- 14.00% and 53.52% +/- 15.02%, respectively, in patients group. There were significant differences between two groups (P < 0.05). According to the results of colonic transit time there were 6 patients with slow transit constipation, 17 patients with outlet dysfunction and 2 patients with normal colonic transit time. The abilities of evacuation were more seriously impaired in patients with outlet dysfunction compared with those patients with slow transit constipation. For the isotope defecography the mean anorectal angles at resting in patient group and normal group were 109 +/- 12 degrees and 101 +/- 17 degrees. There were no significant differences in anorectal angles between patient group and normal group or by both methods of isotope defecography and X-ray defecography. The correlation coefficients for anorectal angles at resting, squeezing and evacuation were 0.87, 0.82 and 0.73, respectively. CONCLUSION: The isotope defecography can be used to evaluate the anorectal function and the ability of defecation dynamically, also it was simple and safe because of the low dose radiation involved.

Adolescent↗
PubMed1986

Alumni perceptions of adequacy of training in diagnostic radiology.

Former residents who completed an accredited university radiology residency between 1953 and 1983 were surveyed using a written questionnaire. Seventy-five percent responded with opinions concerning their satisfaction with the various aspects of their training, including whether the program had met the specific needs of their practice. Most were satisfied with their training. Many believed the program should offer formal training in nonclinical areas such as quality control, equipment selection, administration, economics, and contract negotiations. Nearly all (96%) believed they had been adequately prepared for the Board examination. The majority (75%) believed a postgraduate clinical year was important prior to entering a radiology residency. We believe the written survey is a useful means for gathering data regarding adequacy of residency training. With the current interest in residency program curricula, such data may be useful in the dynamic process of structuring residency programs.

Curriculum↗
PubMed2002

An image analysis algorithm for dendritic spines.

The structure of neuronal dendrites and their spines underlie the connectivity of neural networks. Dendrites, spines, and their dynamics are shaped by genetic programs as well as sensory experience. Dendritic structures and dynamics may therefore be important predictors of the function of neural networks. Based on new imaging approaches and increases in the speed of computation, it has become possible to acquire large sets of high-resolution optical micrographs of neuron structure at length scales small enough to resolve spines. This advance in data acquisition has not been accompanied by comparable advances in data analysis techniques; the analysis of dendritic and spine morphology is still accomplished largely manually. In addition to being extremely time intensive, manual analysis also introduces systematic and hard-to-characterize biases. We present a geometric approach for automatically detecting and quantifying the three-dimensional structure of dendritic spines from stacks of image data acquired using laser scanning microscopy. We present results on the measurement of dendritic spine length, volume, density, and shape classification for both static and time-lapse images of dendrites of hippocampal pyramidal neurons. For spine length and density, the automated measurements in static images are compared with manual measurements. Comparisons are also made between automated and manual spine length measurements for a time-series data set. The algorithm performs well compared to a human analyzer, especially on time-series data. Automated analysis of dendritic spine morphology will enable objective analysis of large morphological data sets. The approaches presented here are generalizable to other aspects of neuronal morphology.

Algorithms↗