Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Dynamic Programming”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,423 records · Page 79Linked to original sources
PubMed2003

nMoldyn: a program package for a neutron scattering oriented analysis of molecular dynamics simulations.

We present a new implementation of the program nMoldyn, which has been developed for the computation and decomposition of neutron scattering intensities from Molecular Dynamics trajectories (Comp. Phys. Commun 1995, 91, 191-214). The new implementation extends the functionality of the original version, provides a much more convenient user interface (both graphical/interactive and batch), and can be used as a tool set for implementing new analysis modules. This was made possible by the use of a high-level language, Python, and of modern object-oriented programming techniques. The quantities that can be calculated by nMoldyn are the mean-square displacement, the velocity autocorrelation function as well as its Fourier transform (the density of states) and its memory function, the angular velocity autocorrelation function and its Fourier transform, the reorientational correlation function, and several functions specific to neutron scattering: the coherent and incoherent intermediate scattering functions with their Fourier transforms, the memory function of the coherent scattering function, and the elastic incoherent structure factor. The possibility to compute memory function is a new and powerful feature that allows to relate simulation results to theoretical studies.

Journal Article↗
PubMed1997

The effect of dynamic strength back exercise and/or a home training program in 57-year-old women with chronic low back pain. Results of a prospective randomized study with a 3-year follow-up period.

STUDY DESIGN: A prospective, randomized investigation. OBJECTIVES: To compare the effect of dynamic strength back muscle training with that of a home training program and to evaluate the long-term effect of the home training program in patients with chronic low back pain. SUMMARY OF BACKGROUND DATA: In a health survey of 57-year-old women, those with chronic low back pain were selected using the Nordic Questionnaire. Of 172 women with low back pain, 74 participated in the study. METHODS: The participants were randomly assigned to either dynamic strength back exercises at a fitness center and a home training program or to the home training program for the first 3 months, after which both groups continued to pursue the home training program. Follow-up observation was by examination at 3 and 12 months and by mailed questionnaire after 3 years. The primary effect variables were disability, sick-leave, and use of health care services. RESULTS: Both training groups manifested significant improvement at the 3- and 12-month follow-up examinations, yet the adherence rate was much better in the group assigned to the fitness center. Those who adhered to the training program for the first year manifested significant improvement according to the 3-year follow-up questionnaire. There was a significant reduction in the number of women on sick-leave and in use of health care services after 1 year, but not after 3 years. CONCLUSIONS: The home training program was as effective as the supervised dynamic strength muscle training program and yielded lasting improvement after at least 1 year of adherence. The adherence rate was much better, however, when the training was supervised at the start.

Back↗
PubMed1999

Dynamic restructuring of a rhythmic motor program by a single mechanoreceptor neuron in lobster.

We have explored the synaptic and cellular mechanisms by which a single primary mechanosensory neuron, the anterior gastric receptor (AGR), reconfigures motor output of the gastric mill central pattern generator (CPG) in the stomatogastric nervous system (STNS) of the lobster Homarus gammarus. AGR is activated in vivo by contraction of the medial tooth protractor muscle gm1 and accesses the gastric CPG via excitation of two in-parallel interneurons, the excitatory commissural gastric (CG) and the inhibitory gastric inhibitor (GI). In the spontaneously active STNS in vitro, weak firing of AGR in time with gastric mill motoneurons (GM) reinforces an ongoing type I gastric mill rhythm in which all gastric teeth power-stroke motoneurons are synchronously active. With strong AGR firing, these phase relationships switch abruptly to a type II pattern in which lateral and medial teeth power-stroke motoneurons fire in antiphase. Our results suggest that these bimodal actions on the gastric mill rhythm depend on the balance of firing of the CG and GI interneurons and that selection of the pathway resides in their different postsynaptic sensitivities to AGR. Whereas high intrinsic firing rates of the CG neuron ensure that the excitatory pathway predominates during low levels of sensory input, strong synaptic facilitation in the GI neuron favors the inhibitory pathway during high levels of receptor activity. Feedback from a single mechanosensory neuron is thus able, in an activity-dependent manner, to specify different motor programs from a single central pattern-generating network.

Animals↗
PubMed2006

Chromatin code, local non-equilibrium dynamics, and the emergence of transcription regulatory programs.

Chromatin is a, if not the, hallmark of eukaryotic life. Any molecular process entailing genomic DNA or the nucleus by default provokes or depends on chromatin structural dynamics on various space and time scales. Chromatin dynamics are result of changes in the physico-chemical properties of the chromatin constituents themselves or the nuclear environment. Chromatin has been found in the former case to undergo many different covalent enzyme-mediated chemical modifications. Their identification sheds light on the molecular mechanisms and the physico-chemical properties underlying chromatin dynamics, and allows the development of quantitative models for the chromatin fiber. The abundance of the different modifications, their dynamics, and short- as well as long-range correlation phenomena between different modifications also point to a second layer of genomic coding implemented at the level of chromatin. Especially, gene regulatory coding seems to depend on such a second-level code. The information-theoretical properties of chromatin in the context of gene regulatory coding are discussed. A model for the emergence of cellular differentiation from the intricate interplay between genomic and chromatin code is presented and discussed in light of recent experimental insights.

Base Sequence↗
PubMedDate not supplied

Monitoring udder health and milk quality using somatic cell counts.

In this article the use of somatic cell counts for monitoring udder health and milk quality is discussed. Somatic cell count dynamics at quarter, cow, herd and population level are discussed and illustrated with examples. Quarter and cow somatic cell counts directly represent the inflammatory status of the mammary gland. Herd and population somatic cell count are related to the inflammatory process in individual cows but much more reflect the udder health status of the herd and the quality of the raw milk in the herd and the population. Application of monitoring tools in herd health management are illustrated using a case study. Understanding infection dynamics requires precise longitudinal data. Monitoring tools are required to find the areas of risk in the herd. It is inevitable that more complete udder health programs and monitoring systems are to be developed and implemented. These programs are necessarily dynamic and complex. Implementation of complete udder health programs should be accompanied by research efforts to further fine-tune these complete udder health control and monitoring programs.

Animals↗
PubMed1995

Quality improvement and critical care nursing.

Within the field of quality in health care there is a move away from quality assurance to a process of Continuous Quality Improvement. This change needs to be considered when designing a program to ensure quality within a critical care environment. There are several approaches available, one of which is the Dynamic Quality Improvement program. This involves solving problems and improving everyday practice whilst focusing on the recipients of the service. It utilises the Dynamic Standard Setting System (DySSSy) to define a professionally agreed level of performance for a chosen population. The standard must be achievable, observable, desirable and measurable. Patient focused nursing activities such as eye care and the prevention of pressure sores can be the basis for standard setting, audit and action to improve the care of the critically ill patient in a comprehensive program of quality initiatives.

Critical Care↗
PubMed2005

A restraint molecular dynamics and simulated annealing approach for protein homology modeling utilizing mean angles.

BACKGROUND: We have developed the program PERMOL for semi-automated homology modeling of proteins. It is based on restrained molecular dynamics using a simulated annealing protocol in torsion angle space. As main restraints defining the optimal local geometry of the structure weighted mean dihedral angles and their standard deviations are used which are calculated with an algorithm described earlier by Doker et al. (1999, BBRC, 257, 348-350). The overall long-range contacts are established via a small number of distance restraints between atoms involved in hydrogen bonds and backbone atoms of conserved residues. Employing the restraints generated by PERMOL three-dimensional structures are obtained using standard molecular dynamics programs such as DYANA or CNS. RESULTS: To test this modeling approach it has been used for predicting the structure of the histidine-containing phosphocarrier protein HPr from E. coli and the structure of the human peroxisome proliferator activated receptor gamma (Ppar gamma). The divergence between the modeled HPr and the previously determined X-ray structure was comparable to the divergence between the X-ray structure and the published NMR structure. The modeled structure of Ppar gamma was also very close to the previously solved X-ray structure with an RMSD of 0.262 nm for the backbone atoms. CONCLUSION: In summary, we present a new method for homology modeling capable of producing high-quality structure models. An advantage of the method is that it can be used in combination with incomplete NMR data to obtain reasonable structure models in accordance with the experimental data.

Algorithms↗
PubMed1995

[Molecular mechanisms of apoptosis in the immune system].

Apoptosis is a controlled death process under regulation by multiple death and survival genes. In the immune systems, apoptosis has important roles in establishment of the mature immune system (embryological programmed cell death), in dynamic maintenance of functional cell number (physiological programmed cell death) and in elimination of unwanted cells (biochemical programmed cell death). The process of apoptosis is regulated by multiple genes and their products depending on different stimuli. The current knowledge on the molecular events of apoptotic cell death, particularly in thymocytes, is reviewed.

Apoptosis↗
PubMed1991

[The effect of different physical training regimens on the dynamics of arterial pressure and physical work capacity in persons with "mild" arterial hypertension].

The influence of three different modes of physical training (PT) on high arterial pressure was estimated in persons suffering from "mild" arterial hypertension. 154 men and women aged 35-54 years were entered into the study. In accordance with two different methods of estimating the initial physical work fitness (PWF), the test subjects were distributed into 4 groups. In these groups, the percentage of aerobic training aimed at the development of stamina was progressively raised. The dynamics of the initial PWF served as a criterion for the efficacy of PT. It has been demonstrated that firstly, both methods of estimating PWF are suitable enough for characterization of the dynamics of PWF, secondly, the decrease of arterial pressure is directly dependent on the effectiveness of the PT programs reflecting the dynamics of PWF, and, thirdly, PT aimed at the development of the general (aerobic) stamina is the most effective nonmedicamentous approach to the reduction of arterial hypertension.

Adult↗
PubMed2000

Learning about the dynamic swallowing process using an interactive multimedia program.

The management of dysphagia is the largest recognized subspecialty in the field of speech-language pathology. Practicing speech-language pathologists require a comprehensive theoretical and functional knowledge base to underpin the safe and effective management of people with dysphagia. Students need to develop an understanding of the normal integrated swallow and how it can be affected to appreciate the assessment or treatment of dysphagia. Although students are well motivated to learn this material, assimilating knowledge of the dynamic nature of the swallow has typically been problematic because of its complex character. The limitations of currently available teaching resources have been addressed by the production of an interactive multimedia program that includes integrated presentation of text, graphics, voice-overs, and video and animation sequences to highlight various aspects of the swallowing process. Students can selectively manipulate parts of this process to understand the normal swallow and to simulate different aspects of dysfunction and the consequent effects on swallow safety and efficiency. Feedback from students, faculty, and experts has demonstrated that The Dynamic Swallow would be a valued tool in the teaching of dysphagia.

CD-ROM↗
PubMed1983

Values clarification as a technique for family planning education.

A Spanish language family planning education program utilizing the dynamics of values clarification has been designed and implemented in the state of Oaxaca, Mexico. The design of the program features three basic personality identification activities to help individuals identify other dimensions of adult life expression than child rearing. In addition, a series of simple and precise scenarios specifically related to family planning are presented. Each scenario is accompanied by a set of valuing questions that direct the learner to respond to the scenario. The activity booklet is entitled, "Clarification De Valores En La Planificacion Familar." The booklet requires the learner to make responses to the learning materials. Responses are then used as a basis for inferring that people are comprehending and above all personalizing knowledge about themselves and their culture and family planning. The program is cross cultural and can be used in Spanish speaking communities in the U.S. Its English language form can be used with English speaking target populations. Statistical analysis of seven critical categories of the program indicated that the shifts in attitudes from pre-to post-values, whether positive or negative (desirable or undesirable), were not significant at the .05 level of confidence. It should, however, be noted that small shifts in the rate of natural increase, or rate of natural decrease for population growth can have a dramatic effect on population growth when multiplied by time.

Contraception↗
PubMed2004

Recommendations for resistance exercise in cardiac rehabilitation. Recommendations of the German Federation for Cardiovascular Prevention and Rehabilitation.

Aerobic endurance training has been an integral component of the international recommendations for cardiac rehabilitation for more than 30 years. Notwithstanding, only in recent years have recommendations for a dynamic resistance-training program been cautiously put forward. The perceived increased risk of cardiovascular complications related to blood pressure elevations are the primary concern with resistance training in cardiac patients; recent studies however have demonstrated that this need not be a contraindication in all cardiac patients. While blood pressure certainly may rise excessively during resistance training, the actual rise depends on a variety of controllable factors including magnitude of the isometric component, the load intensity, the amount of muscle mass involved as well as the number of repetitions and/or the load duration. Intra-arterial blood pressure measurements in cardiac patients have demonstrated that that during low-intensity resistance training [40-60% maximum voluntary contraction (MVC)] with 15-20 repetitions, only modest elevations in blood pressure are revealed, similar to those seen during moderate endurance training. When properly implemented by an experienced exercise therapist, in specific patient groups an individually tailored, medically supervised dynamic resistance training program carries no inherent higher risk for the patient than aerobic endurance training. As an adjunct to endurance training, in selected patients, resistance training can increase muscle strength and endurance, as well as positively influence cardiovascular risk factors, metabolism, cardiovascular function, psychosocial well-being and quality of life. According to present data, resistance training is however not recommended for all patient groups. The appropriate training method and correct performance are highly dependent on each patient's clinical status, cardiac stress tolerance and possible comorbidities. Most studies have used middle-aged men of average normal aerobic performance capacity and with good left-ventricular (LV) function. Data are lacking for high-risk groups, women and older patients. With the current knowledge it is reasonable to include resistance training without any restraints as part of cardiac rehabilitation programs for coronary artery disease (CAD) patients with good cardiac performance capacity (i.e., revascularised and with good myocardial function). As patients with myocardial ischaemia and/or poor left ventricular function may develop wall motion disturbances and/or severe ventricular arrhythmias during resistance exercise, the following criteria are suggested for resistance training: moderate-to-good LV function, good cardiac performance capacity [>5-6 metabolic equivalents of oxygen consumption (METS)=1.4 watt/kg body weight], no symptoms of angina pectoris or ST segment depression under continued maintenance of the medical therapy. Based on available data, this article presents recommendations for risk stratification in cardiac rehabilitation programs with respect to the implementation of dynamic resistance training. Additional recommendations for specific patient groups and detailed directions showing how to structure and implement such therapy programs are presented as well.

Cardiac Rehabilitation↗
PubMed1990

Methodology of ECG interpretation in the Dalhousie program; NOVACODE ECG classification procedures for clinical trials and population health surveys.

The Dalhousie ECG Program was designed specifically for the needs of epidemiologic studies, health surveys, and clinical trials. The program logic is dynamic in that it can accommodate any combination of ECG leads, record length and sampling rate. The NOVACODE module of the program classifies ECGs according to the Minnesota Code, supplemented with new sets of logic criteria for conduction defects, acute myocardial infarction, and serial ECG changes. Improved statistical models are incorporated for enhanced detection of myocardial infarction using the Cardiac Infarction Injury Score, and for quantification of left ventricular mass estimation. It is anticipated that these program improvements will enhance its utility particularly in monitoring progression and regression of cardiac involvement in hypertensive and ischemic heart disease, and in the assessment of the effectiveness of intervention on cardiovascular disease risk factors.

Adolescent↗
PubMed2005

GROMACS: fast, flexible, and free.

This article describes the software suite GROMACS (Groningen MAchine for Chemical Simulation) that was developed at the University of Groningen, The Netherlands, in the early 1990s. The software, written in ANSI C, originates from a parallel hardware project, and is well suited for parallelization on processor clusters. By careful optimization of neighbor searching and of inner loop performance, GROMACS is a very fast program for molecular dynamics simulation. It does not have a force field of its own, but is compatible with GROMOS, OPLS, AMBER, and ENCAD force fields. In addition, it can handle polarizable shell models and flexible constraints. The program is versatile, as force routines can be added by the user, tabulated functions can be specified, and analyses can be easily customized. Nonequilibrium dynamics and free energy determinations are incorporated. Interfaces with popular quantum-chemical packages (MOPAC, GAMES-UK, GAUSSIAN) are provided to perform mixed MM/QM simulations. The package includes about 100 utility and analysis programs. GROMACS is in the public domain and distributed (with source code and documentation) under the GNU General Public License. It is maintained by a group of developers from the Universities of Groningen, Uppsala, and Stockholm, and the Max Planck Institute for Polymer Research in Mainz. Its Web site is http://www.gromacs.org.

Algorithms↗