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PubMed1998

Reducing teenage and unintended pregnancies through client-centered and family-focused school-based family planning programs.

Achievement of the national health goal to reduce teenage and unintended pregnancies through family planning requires a holistic approach to primary prevention. Building upon Rogers' Science of Unitary Human Being, Orem's Self-Care Theory, and Rosenstack's Health Belief Model, a client-centered and family-focused school-based family planning program is proposed as a means to achieve the health goal. FNPs play a pivotal role in development and successful implementation of such a program.

Adolescent↗
PubMed1986

School-based drug education in North America: what is wrong? What can be done?

This article reviews experimental literature concerning the impact of drug (including alcohol and tobacco) education. Major weaknesses are identified with respect to planning, development, implementation, and evaluation of programs. Of special significance are inadequate identification of program objectives and target groups, failure to appreciate the dynamics of effective influence, lack of attention to program dissemination and utilization, and lack of concern with establishing the impact of programs through careful evaluation.

Child↗
PubMed2003

Dynamic quiz bank: a portable tool set for authoring and managing distributed, Web-based educational programs in radiology.

RATIONALE AND OBJECTIVES: The authors performed this study to evaluate a portable, platform-independent software program that enables users from remote sites to transform raw materials (eg, text, images, video) into Web-ready, interactive tutorials and examinations. MATERIALS AND METHODS: The software program evaluated consists of three modules: a network-based interface developed in the Java programming language, an Oracle 8i relational database with liaison software, and shell scripts developed in the Perl programming language to automate the authoring, maintenance, and updating of content in a dynamic quiz bank (DBQ). Four faculty members, one radiology resident, and two undergraduates majoring in computer science volunteered to create questions for the DQB and to evaluate ease of authoring. RESULTS: Faculty members with various levels of computer proficiency were able to establish a comprehensive DQB of more than 1,000 interactive questions. These radiologists reported the scripts reliable and easy to use. The DQB, offered in a pathology course for 2nd-year medical students, was used by 151 students and may have played a role in improving standardized test scores. Eighty-seven percent (n = 131) of the students believed that the DQB was extremely useful as an educational tool. CONCLUSION: The DQB software program facilitated access to, and authoring and maintenance of, Web-based educational materials developed in the departments of radiology and pathology.

Computer-Assisted Instruction↗
PubMed2006

[Response to dynamic strain in human periosteal cells grown in vitro].

The objective of this program is to investigate the biological effect of dynamic strain on human periosteal cells in vitro. Using a well-established model, the Flexercell unit, we placed mechanical stress (50,000 microstrain, 1 Hz and sine wave) on human periosteal cells grown in collagen coated flexible membrane. The time points of proliferative and differentiative properties were assessed by means of cell counting, thymidine incorporation, synthesis of alkaline phosphatase and osteocalcin, and long term of mechanical load induced calcium nodules formation was also demonstrated. The results showed that the application of highly controlled strains exerted a significant effect on human periosteal cells by up regulation of osteogenic properties rather than exercised an influence on proliferation. The results suggested that the promoting effects of dynamic strain on human periosteal cells probably contribute to the biological function of mechanical loading bearing.

Biomechanical Phenomena↗
PubMed1993

Modelling of direct motor program learning in fast human arm motions.

We propose and simulate a new paradigm for organization of motor control in fast and accurate human arm motions. We call the paradigm "direct motor program learning" since the control programs are learned directly without knowing or learning the dynamics of a controlled system. The idea is to approximate the dependence of the motor control programs on the vector of the task parameters rather than to use a model of the system dynamics. We apply iterative learning control and scattered data multivariate approximation techniques to achieve the goal. The advantage of the paradigm is that the control complexity depends neither on the order nor on the nonlinearity of the system dynamics. We simulate the direct motor program learning paradigm in the task of point-to-point control of fast planar human arm motions. Simulation takes into account nonlinear arm dynamics, muscle force dynamics, delay in low-level reflex feedback, time dependence of the feedback gains and coactivation of antagonist muscles. Despite highly nonlinear time-variant dynamics of the controlled system, reasonably good motion precision is obtained over a wide range of the task parameters (initial and final positions of the arm). The simulation results demonstrate that the paradigm is indeed viable and could be considered as a possible explanation for the organization of motor control of fast motions.

Algorithms↗
PubMed1996

Importance of the hydrophobic energy: structural determination of a hypoglycemic drug of the meglitinide family by nuclear magnetic resonance and molecular modeling.

The molecular structure of (2S)-2-benzyl-3-(cis-hexahydro-2-isoindolinylcarbonyl) propionic acid (KAD-1229), a hypoglycemic drug of the meglitinide family, was studied by nuclear magnetic resonance (NMR) and molecular modeling. The results of the NMR experiments indicated that KAD-1229 existed in solution in the form of two stable conformers of equal population, called KADI and KADII in this paper. Three different molecular modelings were then applied: the classical molecular dynamics using the commercial Biosym and Hyperchem softwares and the Prot+ program, which is not based on a dynamical study but on a systematic conformational analysis of the molecule, which includes a term that allows the estimation of the hydrophobic interaction. The modeling results showed the following points. First, in contrast with classical molecular dynamics, which uses restraints from two-dimensional nuclear Overhauser effect (NOE) data, the Prot+ KAD structure provides conformations that support experimental NMR data without any external intervention. In the structures in agreement with NMR data, an important hydrophobic interaction between the phenyl cycle and the perhydroisoindole ring of KAD is observed. This interaction, which seems to play a role in the biological activity of the drug, is lost when no restraints are considered in classical molecular dynamics. Second, the difference between KADI and KADII arises mainly from slight distance geometric differences at the level of the perhydroisoindole and the phenyl rings.

Benzamides↗
PubMed1992

Computer aided technical instruction, (C.A.T.I.).

The article refers to the development of several computer programs designed to fulfil the role of teaching aids in relation to the technological aspects of dentistry. The hardware used was a BBC Master computer, this being a deliberate choice, to demonstrate that it is not necessary to have state of the art computer technology in order to produce very satisfactory computer aided technical instruction packages. All the programs were written in BBC Basic. Computer graphics illustrate and simplify dynamic concepts involved in dental technology. The programs having been developed in house proved to be inexpensive, in addition the program structure allows for easy upgrading. An extract from one of the procedures that serves to make up the modules is included to demonstrate the simplicity of the programming and the modular concept of program development.

Computer Simulation↗
PubMed1990

Dynamic versus static training in patients with rheumatoid arthritis.

Sixty-seven patients with classical or definite rheumatoid arthritis (RA) were studied concerning the effects of standardized physical training on muscle function in the lower extremities. The patients were randomly assigned to four different training groups and were given 6 weeks of training supervised by a physiotherapist at a health care centre. The groups differed according to type (dynamic or static) and extent (12 or 4 times) of training. During this training period as well as for an additional 3 months, the patients carried out programs of exercise at home (either dynamic or static). A significantly greater increase in function during the 6-week period as regards muscle strength, endurance, aerobic capacity, and functional ability was found for the dynamic as compared with the static groups. The findings at follow-up 3 months later were similar. The effectiveness of the programs did not vary with the extent of training. In conclusion, in RA patients, dynamic training gives a greater increase in physical capacity than does static training.

Activities of Daily Living↗
PubMed2000

Differential expression of Bax and Bcl-2 in the assessment of cellular dynamics in fine-needle samples of primary breast carcinomas.

The rates of cell proliferation and programmed cell death (apoptosis) reflect tumor cell dynamics and are considered to directly influence biological progression and tumor response to therapy. Bax and Bcl-2 are members of a gene family that influence apoptosis and have been used as surrogate markers in the evaluation of this process. Sixty-three fine-needle tumor samples from an equal number of patients with breast carcinomas were analyzed for Bax, Bcl-2, and DNA content by flow cytometry. The results were correlated with classical clinicopathological parameters. Bax values varied widely among tumors and showed no significant correlation with any of the clinicopathological parameters analyzed. Bcl-2 levels ranged from 4% to 91%, correlated positively with estrogen (P = 0.0004) and progesterone (P = 0.0045) receptor positivity, and were more associated with low S-phase tumor values. In contrast, high S-phase values correlated with estrogen receptor negativity, high grade, and DNA aneuploidy. The study results indicate that Bcl-2 and S-phase analysis of fine-needle samples of breast carcinomas provide a convenient tool for the assessment of these tumors.

Adult↗
PubMed1992

The dynamics of health insurance among the near elderly.

Data from the Longitudinal Survey of Income and Program Participation were used to examine the dynamics of health insurance among persons 55 to 64 years of age. Persons in this age range are especially vulnerable to incurring high health care costs. Between the summer of 1983 and early 1986, 21% of persons 55 to 64 years of age experienced some time without health insurance. Approximately one fifth were continuously uninsured (4%) while the rest spent only part of the time without coverage, typically 4 months or less. Women were particularly vulnerable to periods without insurance, accounting for approximately twice as many of them as did men. Unlike younger cohorts, the coverage lost among the near elderly tended not to be employer coverage. Instead, most uninsured spells were ones in which individually purchased coverage was lost. Most spell beginnings were unrelated to changes in household employment, yet most spells ended when employment within the household increased. Some currently proposed reforms to expand health insurance, such as an all-employer mandate, a "pay-or-play" mandate, and extending Medicaid to persons in poverty, are less effective in reaching this medically high-risk population than in reaching younger persons who are uninsured.

Employment↗
PubMed1989

Dynamic hepatic CT.

A technique for incremental dynamic computed tomography (CT) of the liver with boluses of contrast material (with a 50-g iodine load) administered intravenously is described. For most focal liver lesions, which are hypovascular in relation to normal hepatic parenchyma, bolus contrast material enhancement and incremental dynamic scanning improve detectability, compared with that yielded by nondynamic, contrast material infusion techniques. The bolus contrast-enhanced dynamic scan technique is reproducible and of value in patients undergoing sequential CT for assessment of tumor bulk response to chemotherapy. Patients who are potential candidates for resection of focal hepatic lesions should preoperatively undergo intraarterial contrast-enhanced CT. Intravenous bolus enhanced dynamic hepatic CT can be extended to cover more than one anatomic region (eg, abdomen and thorax), as in patients undergoing CT for staging lung carcinoma. In these patients, incremental scan sequences are programmed caudad to cephalad. Incremental dynamic CT is also an appropriate technique to use in cooperative patients who have suffered blunt abdominal trauma.

Contrast Media↗
PubMed2006

[Real-time volume rendering of medical 3D dynamic ultrasound].

Dynamic 3D ultrasound is a very promising technology for clinical use, but not being a Cartesian 3D dataset, 3D ultrasound data can not be visualized directly with real-time volume rendering accelerated by 3D texture hardware. In this paper, fast volume rendering using 3D texture hardware acceleration is introduced and modern PC graphics card architecture analyzed. A modified method is proposed to obtain real-time volume rendering of dynamic 3D ultrasound data by programming vertex shader in GPU. Experimental results show that 3D ultrasound data can be rendered with real-time speed in normal PC platform. The method can be widely applied in future 3D dynamic ultrasound clinical research.

Algorithms↗
PubMed2006

Chaos in computer performance.

Modern computer microprocessors are composed of hundreds of millions of transistors that interact through intricate protocols. Their performance during program execution may be highly variable and present aperiodic oscillations. In this paper, we apply current nonlinear time series analysis techniques to the performances of modern microprocessors during the execution of prototypical programs. Our results present pieces of evidence strongly supporting that the high variability of the performance dynamics during the execution of several programs display low-dimensional deterministic chaos, with sensitivity to initial conditions comparable to textbook models. Taken together, these results show that the instantaneous performances of modern microprocessors constitute a complex (or at least complicated) system and would benefit from analysis with modern tools of nonlinear and complexity science.

Journal Article↗
PubMed1999

[Three-dimensional reconstruction of functional brain images].

We consider PET (positron emission tomography) measurement with SPM (Statistical Parametric Mapping) analysis to be one of the most useful methods to identify activated areas of the brain involved in language processing. SPM is an effective analytical method that detects markedly activated areas over the whole brain. However, with the conventional presentations of these functional brain images, such as horizontal slices, three directional projection, or brain surface coloring, makes understanding and interpreting the positional relationships among various brain areas difficult. Therefore, we developed three-dimensionally reconstructed images from these functional brain images to improve the interpretation. The subjects were 12 normal volunteers. The following three types of images were constructed: 1) routine images by SPM, 2) three-dimensional static images, and 3) three-dimensional dynamic images, after PET images were analyzed by SPM during daily dialog listening. The creation of images of both the three-dimensional static and dynamic types employed the volume rendering method by VTK (The Visualization Toolkit). Since the functional brain images did not include original brain images, we synthesized SPM and MRI brain images by self-made C++ programs. The three-dimensional dynamic images were made by sequencing static images with available software. Images of both the three-dimensional static and dynamic types were processed by a personal computer system. Our newly created images showed clearer positional relationships among activated brain areas compared to the conventional method. To date, functional brain images have been employed in fields such as neurology or neurosurgery, however, these images may be useful even in the field of otorhinolaryngology, to assess hearing and speech. Exact three-dimensional images based on functional brain images are important for exact and intuitive interpretation, and may lead to new developments in brain science. Currently, the surface model is the most common method of three-dimensional display. However, the volume rendering method may be more effective for imaging regions such as the brain.

Brain↗
PubMed2006

Voiding dysfunction in children. Pelvic-floor exercises or biofeedback therapy: a randomized study.

Fifty-six patients 5.9-15.2 years old with dysfunctional elimination syndrome (DES) unimproved by previous therapies were randomly distributed into two voiding training programs: group 1 contained 26 patients submitted to 24 training sessions over a 3-month period; group 2 contained 30 patients submitted to 16 sessions over a 2-month period. Both groups adhered to a voiding and drinking schedule, received instruction on adequate toilet posture, were reinforced through the maintenance of voiding diaries, and went through proprioceptive and pelvic floor muscle training (Kegel exercises). Group 2 patients also received biofeedback therapy. Clinical evaluation was carried out before each program's initiation and 1, 6, and 12 months after each program's termination. All patients were submitted to renal ultrasonography and dynamic ultrasonography before and 6 months after each program's conclusion. Millivoltage recordings of pelvic floor muscles were compared before and after training. Urinary continence was improved after completion of either training program. Only those patients who received biofeedback training showed a significant decrease in postvoiding residual (PVR) urine as detected by dynamic ultrasonography. Our results show that either training regime can reduce episodic urinary incontinence and urinary tract infection but that further study is required to identify the optimal training duration.

Adolescent↗
PubMed2004

Heart rate dynamics after controlled training followed by a home-based exercise program.

Daily aerobic training results in autonomic control of the heart toward vagal dominance. The constancy of vagal dominance after controlled training followed by a home-based training program in accordance with contemporary guidelines is not known. We set out here to study whether the vagal dominance induced by 8 weeks of controlled aerobic training is preserved after a 10-month home-based training program. For the controlled study, healthy men were randomized as training (n=18) and control subjects (n=6). The training was started by a supervised 8-week period with six training sessions a week [45 (15) min each] at an intensity of 70-80% of maximum heart rate, followed by a home-based training program for 10 months in accordance with the American College of Sports Medicine recommendations. Cardiovascular autonomic function was assessed by analyzing HR variability over a 24-h period and separately during the night hours (midnight-6 a.m.). Maximal running performance improved during the controlled training 16 (7)% (range 4-31%, P<0.001) and remained 8 (8)% (range -3 to 23%, P<0.001) above the baseline level after the home-based training program. At night, the vagally mediated high-frequency (HF) power of R-R intervals increased during the controlled training from 6.7 (1.3) to 7.3 (1.1) ln ms2 ( P<0.001) and remained higher than the baseline after the home-based training [7.0 (1.3) ln ms2, P<0.05]. The changes in running performance correlated with the changes in HF power at night (r=0.41, P<0.05) and over 24 h (r=0.44, P<0.05) after the home-based training program. Similarly, the changes in body mass index correlated with the changes in HF power over 24 h (r=-0.44, P<0.05) after the home-based training program. The high vagal outflow to the heart after the home-based training is associated with good physical performance and body mass control.

Adaptation, Physiological↗

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