Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 25
Filter
Add more filters










Publication year range
1.
Disabil Health J ; 17(3): 101626, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38641454

ABSTRACT

BACKGROUND: People with disabilities (PWD) commonly experience difficulties in accessing their environments, which can lead to restricted participation in outdoor leisure-time physical activity. Participating in outdoor leisure-time physical activity (OLTPA) provides health and social benefits to PWD and benefits to the communities in which they live. OBJECTIVE: The aim of the study was to identify features existing in digital platforms that facilitate access to OLTPA for PWD. METHODS: A scoping review was conducted in four library databases and in Google advance search to identify relevant scientific and grey literature, and websites. Each step of the review was independently conducted by two co-authors who confirmed consensus of results. Descriptive data analyses were performed. RESULTS: Seven scientific studies and ten websites were included in the scoping review. Seven presented mobile apps, nine presented a website and one presented an online database. Sources reported five main obstacles to using digital platforms that support access to physical activities (e.g., lack of digital literacy, technical issues, unintuitive design), and 10 facilitators (e.g., possibility to personalize your online space, accessibility features of the navigation). Among these sources, a trend emerged in the most important factors and features to consider for the visuals and navigation of the platforms. CONCLUSION: The features of digital platforms that facilitate access to OLTPA include intuitive design compliant with accessibility guidelines and supported by navigation tools, personalization of the online space, and features for social interactions.


Subject(s)
Disabled Persons , Exercise , Internet , Leisure Activities , Mobile Applications , Humans
2.
Appl Opt ; 58(35): 9540-9547, 2019 Dec 10.
Article in English | MEDLINE | ID: mdl-31873552

ABSTRACT

Two-dimensional (2D) beam profiling is an emerging technique used to characterize the beam homogeneity in dental light-curing units (LCUs). This project developed a method to combine multiple 2D beam profiles that had been measured along the beam path to create a 3D profile of the beam. This allowed a quantitative investigation of beam divergence and homogeneity at different distances from the source. To illustrate the use of this technique, four representative dental LCUs were measured. In addition, the selected dental LCUs demonstrated the effects of LCU design, particularly that of fiber optic light guides, on beam quality. The results show the value of a program that can recombine multiple beam profile images made at different distances from the source to create a 3D beam profile of a light beam.

3.
J Dent ; 53: 44-50, 2016 10.
Article in English | MEDLINE | ID: mdl-27373167

ABSTRACT

OBJECTIVES: This study measured the transmission of light in the 'violet' (350≤λ≤425nm) and 'blue' (425<λ≤550nm) spectral ranges from a polywave(®) LED curing light through different thicknesses of four commercial, resin-based composites (RBCs). MATERIAL AND METHODS: Samples of conventional layered RBCs (Tetric EvoCeram A2, Filtek Supreme Ultra A2B), and bulk-curing resins (Tetric EvoCeram Bulk Fill IVA, and SureFil SDR Flow U) were prepared. Three samples of each RBC were made at thicknesses of 0.1, 0.7, 1, 2, and 4-mm. The uncured RBC specimens were affixed at the entrance aperture of a 6-inch integrating sphere and light-cured once for 20s using a polywave(®) LED curing light (Bluephase G2) on its high power setting. The spectral radiant power transmitted through each RBC in the 'violet' and 'blue' regions was measured using a fiberoptic spectrometer. RESULTS: As RBC thickness increased, an exponential attenuation of transmitted light was measured (R(2)>0.98). Attenuation was greater for the 'violet' than for the 'blue' spectral regions. At the light tip, the violet light component represented 15.4% of the light output. After passing through 4-mm of RBC, the violet light represented only between 1.2-3.1% of the transmitted light depending on the RBC. Depending on RBC, approximately 100mW from the Bluephase G2 was transmitted through 0.1-mm of RBC in the 'violet' range, falling at most to 11mW after passing through 2-mm of RBC, and to only 2mW at 4-mm depth. CONCLUSIONS: Increasing RBC thickness results in an exponential decrease in light transmission. This attenuation is RBC-dependent with shorter wavelengths (violet) attenuated to a greater extent than longer wavelengths (blue). CLINICAL RELEVANCE: Despite the increased translucency of bulk curing RBCs, spectral radiant power shorter than 425nm from a curing light is unlikely to be effective at a depth of 4-mm or more.


Subject(s)
Dental Materials , Color , Composite Resins , Curing Lights, Dental , Light , Light-Curing of Dental Adhesives , Materials Testing
4.
Dent Mater ; 32(8): 1026-35, 2016 08.
Article in English | MEDLINE | ID: mdl-27316433

ABSTRACT

OBJECTIVE: To investigate the time evolution of the two dimensional axial shrinkage field for two dental resins in the bonded disk geometry and further test the bonded-disk method. METHODS: An interferometric technique employing a camera was used to image the 2D axial shrinkage field when polymerizing dental resins in real time both during and after light exposure. Four different beam profiles from two light curing units and three sample geometries were utilized to investigate their roles on the 2D axial shrinkage field. RESULTS: The 2D axial shrinkage field correlates qualitatively with the beam profile shortly after the start of light exposure but takes on distinct shapes caused by the rigidity of the coverslip, beam profile, and the resin viscoelasticity. SIGNIFICANCE: Using the conventional bonded disk geometry and uniform beam profile from a light curing unit, the axial 2D shrinkage field was uniform to within 4% in the central part of bonded disk samples.


Subject(s)
Composite Resins , Curing Lights, Dental , Dental Stress Analysis , Kinetics , Materials Testing , Resins, Synthetic , Viscosity
5.
J Dent ; 44: 20-6, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26546716

ABSTRACT

OBJECTIVES: For improved inter-study reproducibility and ultimately improved patient care, researchers and dentists need to know what electromagnetic radiation (light) is emitted from the light-curing unit (LCU) they are using and what is received by the resin. This information cannot be obtained from a dental radiometer, even though many studies have used a dental radiometer. METHODS: The light outputs from six LCUs (two QTH and four broad-spectrum LED units) were collected in real-time using an integrating sphere connected to a fiberoptic spectrometer during different light exposures. RESULTS: It was found that the spectral emissions were unique to each LCU, and there was no standardization in what was emitted on the various ramp (soft-start) settings. Relative to the normal use setting, using the ramp setting reduced the radiant energy (J) delivered from each LCU. For one of the four broad-spectrum LED LCUs, the spectral emissions in the violet range did not increase when the overall radiant power output was increased. In addition, this broad-spectrum LED LCU emitted no light from the violet LED chip for the first 5s and only emitted violet light when the ramp phase finished. CONCLUSIONS: A single irradiance value derived from a dental radiometer or from a laboratory grade power meter cannot adequately describe the output from the LCU. Manufacturers should provide more information about the light output from their LCUs. Ideally, future assessments and research publications that include resin photopolymerization should report the spectral radiant power delivered from the LCU throughout the entire exposure cycle.


Subject(s)
Curing Lights, Dental , Composite Resins/chemistry , Dental Materials , Electromagnetic Radiation , Light , Materials Testing , Photometry/methods , Radiation Dosage , Radiometry/instrumentation , Radiometry/methods , Reproducibility of Results , Semiconductors , Technology, Dental/instrumentation
6.
Oper Dent ; 41(4): 397-408, 2016.
Article in English | MEDLINE | ID: mdl-26652017

ABSTRACT

Recently, "budget" dental light-emitting diode (LED)-based light-curing units (LCUs) have become available over the Internet. These LCUs claim equal features and performance compared to LCUs from major manufacturers, but at a lower cost. This study examined radiant power, spectral emission, beam irradiance profiles, effective emission ratios, and the ability of LCUs to provide sustained output values during the lifetime of a single, fully charged battery. Three examples of each budget LCU were purchased over the Internet (KY-L029A and KY-L036A, Foshan Keyuan Medical Equipment Co, and the Woodpecker LED.B, Guilin Woodpecker Medical Instrument Co). Major dental manufacturers provided three models: Elipar S10 and Paradigm (3M ESPE) and the Bluephase G2 (Ivoclar Vivadent). Radiant power emissions were measured using a laboratory-grade thermopile system, and the spectral emission was captured using a spectroradiometer system. Irradiance profiles at the tip end were measured using a modified laser beam profiler, and the proportion of optical tip area that delivered in excess of 400 mW/cm(2) (termed the effective emission ratio) was displayed using calibrated beam profile images. Emitted power was monitored over sequential exposures from each LCU starting at a fully charged battery state. The results indicated that there was less than a 100-mW/cm(2) difference between manufacturer-stated average tip end irradiance and the measured output. All the budget lights had smaller optical tip areas, and two demonstrated lower effective emission ratios than did the units from the major manufacturers. The budget lights showed discontinuous values of irradiance over their tip ends. One unit delivered extremely high output levels near the center of the light tip. Two of the budget lights were unable to maintain sustained and stable light output as the battery charge decreased with use, whereas those lights from the major manufacturers all provided a sustained light output for at least 100 exposures as well as visual and audible indications that the units required recharging.


Subject(s)
Curing Lights, Dental , Electric Power Supplies , Composite Resins , Materials Testing
7.
Oper Dent ; 40(6): 662-72, 2015.
Article in English | MEDLINE | ID: mdl-26237638

ABSTRACT

OBJECTIVES: This study evaluated the effect of using three commercial light curing units (LCUs) delivering a range of irradiance values, but delivering similar radiant exposures on the depth of cure of two different resin-based composites (RBCs). METHODS: A conventional hybrid RBC (Z100 shade A2, 3M ESPE) or a bulk fill RBC (Tetric EvoCeram Bulk Fill shade IVA, Ivoclar Vivadent) was packed into a 10-mm deep semicircular metal mold with a 2-mm internal radius. The RBC was exposed to light from a plasma-arc-curing (PAC) light (Sapphire Plus, DenMat) for five seconds, a quartz-tungsten-halogen (QTH) light (Optilux 501, Kerr) for 40 seconds, or a light-emitting-diode (LED) light (S10, 3M ESPE) for 20 seconds and 40 seconds (control). The Knoop microhardness was then measured as soon as possible at the top surface and at three points every 0.5 mm down from the surface. For each RBC, a repeated measures analysis of variance (ANOVA) model was used to predict the Knoop hardness in a manner analogous to a standard regression model. This predicted value was used to determine at what depth the RBC reached 80% of the mean hardness achieved at the top surface with any light. RESULTS: The PAC light delivered an irradiance and radiant exposure of 7328 mW/cm(2) and 36.6 J/cm(2), respectively, to the RBCs; the QTH light delivered 936 mW/cm(2) and 37.4 J/cm(2) and in 20 seconds the LED light delivered 1825 mW/cm(2) and 36.5 J/cm(2). In 40 seconds, the control LED light delivered a radiant exposure of 73.0 J/cm(2). For Z100, using 80% of the maximum hardness at the top surface as the criteria for adequate curing, all light exposure conditions achieved the 2.0-mm depth of cure claimed by the manufacturer. The LED light used for 40 seconds achieved the greatest depth of cure (5.0 mm), and the PAC light used for five seconds, the least (2.5 mm). Tetric EvoCeram Bulk Fill achieved a 3.5-mm depth of cure when the broad-spectrum QTH light was used for 40 seconds delivering 37.4 J/cm(2). It required a 40-second exposure time with the narrow-spectrum LED, delivering approximately 73 J/cm(2) to reach a depth of cure of 4 mm. CONCLUSIONS: When delivering a similar radiant exposure of 37 J/cm(2), the QTH (40 seconds) and LED (20 seconds) units achieved a greater depth of cure than the PAC (five seconds) light. For both resins, the greatest depth of cure was achieved when the LED light was used for 40 seconds delivering 73 J/cm(2) (p<0.05).


Subject(s)
Composite Resins/radiation effects , Dental Restoration, Permanent/methods , Silicon Dioxide/radiation effects , Zirconium/radiation effects , Composite Resins/chemistry , Curing Lights, Dental , Dental Restoration, Permanent/instrumentation , Hardness , Humans , Materials Testing , Silicon Dioxide/chemistry , Zirconium/chemistry
8.
Mil Med ; 178(7): 767-74, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23820351

ABSTRACT

The Concussion Restoration Care Center has used the Automated Neuropsychological Assessment Metrics version 4 Traumatic Brain Injury (ANAM4 TBI) battery in clinical assessment of concussion. The study's aim is to evaluate the prognostic utility of the ANAM4 TBI. In 165 concussed active duty personnel (all ultimately returned to duty) seen and tested on the ANAM4 TBI on days 3 and 5 (median times) from their injury, Spearman's ρ statistics showed that all performance subtests (at day 5) were associated with fewer days return-to-duty (RTD) time, whereas concussion history or age did not. Kruskal-Wallis statistics showed that ANAM4 TBI, loss of consciousness, and post-traumatic amnesia were associated with increased RTD time; ANAM4 TBI reaction time-based subtests, collectively, showed the largest effect sizes. A survival analysis using a Kaplan-Meier plot showed that the lowest 25% on the reaction time-based subtests had a median RTD time of 19 days, whereas those in the upper 25% had a median RTD time of approximately 7 days. Results indicate that until validated neurocognitive testing is introduced, the ANAM4 TBI battery, especially reaction time-based tests, has prognostic utility.


Subject(s)
Brain Concussion/physiopathology , Military Medicine , Military Personnel , Reaction Time , Return to Work , Adult , Female , Humans , Male , Neuropsychological Tests , Predictive Value of Tests , Prognosis , United States , Young Adult
9.
Mil Med ; 177(1): 48-51, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22338979

ABSTRACT

Concussions are the most frequent battle injury sustained in Afghanistan. The Concussion Restoration Care Center provides multidisciplinary care to concussed service members in theater. The Concussion Restoration Care Center has managed over 500 concussions, the majority being from improvised explosive device (IED) blasts. Syncope following a concussion without a loss of consciousness is rarely reported in the literature. The pathophysiology of concussion from a blast injury may be distinct from a concussion secondary to blunt trauma. Two cases of syncope following concussions with an alteration of consciousness are presented, and a mechanism of action is proposed. Post-IED blast concussive symptom frequency at initial presentation on a cohort of patients is reported, with 1.3% of patients experiencing postconcussive syncope. Syncope following an IED blast may be related to centrally mediated autonomic dysregulation at the brain stem level. Syncope should be added to the list of possible symptoms that occur following concussions, in particular concussions following a blast injury.


Subject(s)
Autonomic Nervous System/physiopathology , Blast Injuries/physiopathology , Brain Concussion/physiopathology , Military Personnel , Syncope/physiopathology , Adult , Biomechanical Phenomena , Humans , Male
10.
Appl Opt ; 36(16): 3622-34, 1997 Jun 01.
Article in English | MEDLINE | ID: mdl-18253384

ABSTRACT

We have carried out the transmission spectroscopy and obtained the imaginary part of the refractive index k of sulfate and nitrate aqueous solutions in the spectral range between 0.7 and 2.6 microm for several concentrations at temperatures of T = 24 degrees C and T = -24 degrees C. A linear interpolation with volume fraction is found to reproduce the measured k spectra of the ammonium solutions.

11.
Appl Opt ; 34(28): 6582-6, 1995 Oct 01.
Article in English | MEDLINE | ID: mdl-21060513

ABSTRACT

New accurate values of the imaginary part of the refractive index k of polycrystalline ice at T = -22 °C are reported. The k spectrum in the 1.43-2.89-µm region was found to be in excellent agreement with the most recent study, and the data in the 3.35-7.81-µm range eliminate the large existing uncertainty in the 3.5-4.3-µm region.

13.
Appl Opt ; 32(19): 3531-40, 1993 Jul 01.
Article in English | MEDLINE | ID: mdl-20829977

ABSTRACT

New accurate values of the imaginary part, k, of the refractive index of water at T = 22 °C, supercooled water at T = -8 °C and polycrystalline ice at T = -25 °C are reported. The k spectrum for water in the spectral region 0.65-2.5 µm is found to be in excellent agreement with those of previous studies. The k values for polycrystalline ice in the 1.44-2.50-µm region eliminate the large uncertainties existing among previously published conflicting sets of data. The imaginary part of refractive index of supercooled water shows a systematic shift of absorption peaks toward the longer wavelengths compared with that of water at warmer temperatures.

14.
Int J Epidemiol ; 19(3): 483-90, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2262237

ABSTRACT

Patterns of cancer mortality within five population density quintiles in Upstate New York (New York State, exclusive of New York City), were investigated between 1978 and 1982. Sex-specific standardized mortality ratios (SMRs) were calculated within each population density quintile for all cancer deaths combined and for site-specific cancer deaths based on cancer mortality patterns exhibited by the general population of New York State, exclusive of New York City. Areas with the highest population density demonstrated a 12% excess of cancer deaths among males and a 6% excess among females. In contrast, areas with the lowest population density exhibited lower cancer mortality, among both males (9% less) and females (7% less). Males demonstrated a significant linear relationship between increasing population density and deaths for all cancer sites combined and for cancers of the oral cavity and pharynx, oesophagus, stomach, colon, gallbladder, pancreas, lung, prostate, and kidney. Among females, a significant linear relationship was observed between increasing population density and deaths for all cancer sites combined and for deaths due to cancers of the stomach, colon, liver and breast. Deaths due to cancers of the rectum, malignant melanomas of the skin, and cervix also exhibited unusual patterns of mortality across the population density quintiles. These data are most useful in generating hypotheses for further studies to define specific aetiological factors operating within population density groupings. Population density, as measured in this investigation, may represent a surrogate measure for other factors which are related to cancer morbidity and cancer mortality.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Neoplasms/mortality , Population Density , Female , Humans , Male , Melanoma/mortality , Neoplasms/epidemiology , New York/epidemiology , Rural Health , Sex Factors , Urban Health
15.
Phys Rev Lett ; 61(16): 1882-1884, 1988 Oct 17.
Article in English | MEDLINE | ID: mdl-10038922
17.
Appl Opt ; 25(2): 171-2, 1986 Jan 15.
Article in English | MEDLINE | ID: mdl-20445681
20.
Can J Microbiol ; 26(12): 1465-72, 1980 Dec.
Article in English | MEDLINE | ID: mdl-7016278

ABSTRACT

A R-plasmid-containing fil mutant of Escherichia coli strain B, when exposed to chloramphenical (CMP) plus streptomycin (Sm) after irradiation, achieved 100% ultraviolet (UV) recovery from doses that otherwise kill over 90% of the cells. UV-induced filament cells with R plasmids are very UV sensitive regardless of the treatment after the filament-inducing irradiation. The exposure to CMP and Sm can be delayed after irradiation and still rescue filament cells from UV death even when grown on antibiotic-free agar. Development of UV-induced filament cells in CMP-Sm liquid medium increases the number of irradiated cells that will recover the ability to divide even when transferred to antibiotic-free agar soon after irradiation. The results suggest that the recovery of cell division by UV-induced filaments with R plasmids can be accomplished by contact with antibiotics even after extensive "unbalanced growth" or by growing in liquid medium throughout a critical period following irradiation.


Subject(s)
Chloramphenicol/pharmacology , Escherichia coli/radiation effects , R Factors , Streptomycin/pharmacology , Ultraviolet Rays , Cell Division/drug effects , Culture Media , DNA Repair
SELECTION OF CITATIONS
SEARCH DETAIL
...