The Intersection of Dreams and Reality: An Expansion of Temporal Distance Theory to Experiential Purchases

ERIC Educational Resources Information Center

Grube, Ann M.

2014-01-01

This research was designed to expand the applications of Psychological Distance (PD) Theory by studying the effects of time on the importance of criteria used to evaluate institutions of higher learning. It is intended to help administrators market more effectively by determining how future intentions (to go back to school someday) transition into…

Silica coating on alumina ceramic: comparison of three chairside air-abrasion devices working for different times and distances.

PubMed

Pestana Passos, S; Dias Vanderlei, A; Ozcan, M; Felipe Valandro, L F; Felipe Valandro, L

2011-03-01

This study evaluated, by scanning electron microscope (SEM) and EDS, the effect of different strategies for silica coating (sandblasters, time and distance) of a glass-infiltrated ceramic (In-Ceram Alumina). Forty-one ceramic blocks were produced. For comparison of the three air-abrasion devices, 15 ceramic samples were divided in three groups (N.=5): Bioart, Microetcher and Ronvig (air-abrasion parameters: 20 s at a distance of 10 mm). For evaluation of the time and distance factors, ceramic samples (N.=5) were allocated in groups considering three applied times (5 s, 13 s and 20 s) and two distances (10 mm and 20 mm), using the Ronvig device. In a control sample, no surface treatment was performed. After that, the micro-morphologic analyzes of the ceramic surfaces were made using SEM. EDS analyzes were carried out to detect the % of silica on representative ceramic surface. ANOVA and Tukey tests were used to analyze the results. One-way ANOVA showed the silica deposition was different for different devices (P=0.0054). The Ronvig device promoted the highest silica coating compared to the other devices (Tukey test). Two-way ANOVA showed the distance and time factors did not affect significantly the silica deposition (application time and distance showed no statistical difference). The Ronvig device provided the most effective silica deposition on glass-infiltrated alumina ceramic surface and the studied time and distance for air-abrasion did not affect the silica coating.

Verification of endocrinological functions at a short distance between parametric speakers and the human body.

PubMed

Lee, Soomin; Katsuura, Tetsuo; Shimomura, Yoshihiro

2011-01-01

In recent years, a new type of speaker called the parametric speaker has been used to generate highly directional sound, and these speakers are now commercially available. In our previous study, we verified that the burden of the parametric speaker was lower than that of the general speaker for endocrine functions. However, nothing has yet been demonstrated about the effects of the shorter distance than 2.6 m between parametric speakers and the human body. Therefore, we investigated the distance effect on endocrinological function and subjective evaluation. Nine male subjects participated in this study. They completed three consecutive sessions: a 20-min quiet period as a baseline, a 30-min mental task period with general speakers or parametric speakers, and a 20-min recovery period. We measured salivary cortisol and chromogranin A (CgA) concentrations. Furthermore, subjects took the Kwansei-gakuin Sleepiness Scale (KSS) test before and after the task and also a sound quality evaluation test after it. Four experiments, one with a speaker condition (general speaker and parametric speaker), the other with a distance condition (0.3 m and 1.0 m), were conducted, respectively, at the same time of day on separate days. We used three-way repeated measures ANOVA (speaker factor × distance factor × time factor) to examine the effects of the parametric speaker. We found that the endocrinological functions were not significantly different between the speaker condition and the distance condition. The results also showed that the physiological burdens increased with progress in time independent of the speaker condition and distance condition.

A Randomized Trial Evaluating Short-term Effectiveness of Overminus Lenses in Children 3 to 6 Years of Age with Intermittent Exotropia.

PubMed

Chen, Angela M; Holmes, Jonathan M; Chandler, Danielle L; Patel, Reena A; Gray, Michael E; Erzurum, S Ayse; Wallace, David K; Kraker, Raymond T; Jensen, Allison A

2016-10-01

To evaluate the short-term effectiveness of overminus spectacles in improving control of childhood intermittent exotropia (IXT). Randomized, clinical trial. A total of 58 children aged 3 to <7 years with IXT. Eligibility criteria included a distance control score of 2 or worse (mean of 3 measures during a single examination) on a scale of 0 (exophoria) to 5 (constant exotropia) and spherical equivalent refractive error between -6.00 diopters (D) and +1.00 D. Children were randomly assigned to overminus spectacles (-2.50 D over cycloplegic refraction) or observation (non-overminus spectacles if needed or no spectacles) for 8 weeks. The primary outcome was distance control score for each child (mean of 3 measures during a single examination) assessed by a masked examiner at 8 weeks. Outcome testing was conducted with children wearing their study spectacles or plano spectacles for the children in the observation group who did not need spectacles. The primary analysis compared mean 8-week distance control score between treatment groups using an analysis of covariance model that adjusted for baseline distance control, baseline near control, prestudy spectacle wear, and prior IXT treatment. Treatment side effects were evaluated using questionnaires completed by parents. At 8 weeks, mean distance control was better in the 27 children treated with overminus spectacles than in the 31 children who were observed without treatment (2.0 vs. 2.8 points, adjusted difference = -0.75 points favoring the overminus group; 2-sided 95% confidence interval, -1.42 to -0.07 points). Side effects of headaches, eyestrain, avoidance of near activities, and blur appeared similar between treatment groups. In a pilot randomized clinical trial, overminus spectacles improved distance control at 8 weeks in children aged 3 to <7 years with IXT. A larger and longer randomized trial is warranted to assess the effectiveness of overminus spectacles in treating IXT, particularly the effect on control after overminus treatment has been discontinued. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Geometric effects resulting from the asymmetry of dipping fault: Hanging wall/ footwall effects

NASA Astrophysics Data System (ADS)

Wang, Dong; Xie, Li-Li; Hu, Jin-Jun

2008-05-01

Root-mean-square distance D rms with characteristic of weighted-average is introduced in this article firstly. D rms can be used to capture the general proximity of a site to a dipping fault plane comparing with the rupture distance D rup and the seismogenic distance D seis. Then, using D rup, D seis and D rms, the hanging wall/footwall effects on the peak ground acceleration (PGA) during the 1999 Chi-Chi earthquake are evaluated by regression analysis. The logarithm residual shows that the PGA on hanging wall is much greater than that on footwall at the same D rup or D seis when the D rup or D seis is used as site-to-source distance measure. In contrast, there is no significant difference between the PGA on hanging wall and that on footwall at the same D rms when D rms is used. This result confirms that the hanging wall/footwall effect is mainly a geometric effect caused by the asymmetry of dipping fault. Therefore, the hanging wall/footwall effect on the near-fault ground motions can be ignored in the future attenuation analysis if the root-mean-square distance D rms is used as the site-to-source distance measure.

Differential effects on socioeconomic groups of modelling the location of mammography screening clinics using Geographic Information Systems.

PubMed

Hyndman, J C; Holman, C D

2000-06-01

To evaluate spatial access to mammography clinics and to investigate whether relocating clinics can improve global access. To determine whether any change in access is distributed equitably between different social groups. The study was undertaken in Perth, Western Australia in 1996. It was an analysis of travel distances to mammography clinics, comparing distances to the pattern of existing clinics and modelled relocated clinics. The study population was the 151,162 women aged 40-64 years resident in Perth in 1991. Overall travel distances to the existing clinics was reduced by 14% when a GIS system was used to relocate them so as to minimise the travel distance for all women. The travel distance of the most disadvantaged groups fell by 2% and by 24% for the least disadvantaged group. GIS modelling can be used to advantage to evaluate potential locations for screening clinics that improve the access for the target population, however global analysis should be supplemented by analysis of special groups to ensure that no group is disadvantaged by the proposal. If new technology is not used to evaluate the placement of health services, population travel distances may be greater than necessary, with possible impacts on attendance rates.

Thermal motion in proteins: Large effects on the time-averaged interaction energies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goethe, Martin, E-mail: martingoethe@ub.edu; Rubi, J. Miguel; Fita, Ignacio

As a consequence of thermal motion, inter-atomic distances in proteins fluctuate strongly around their average values, and hence, also interaction energies (i.e. the pair-potentials evaluated at the fluctuating distances) are not constant in time but exhibit pronounced fluctuations. These fluctuations cause that time-averaged interaction energies do generally not coincide with the energy values obtained by evaluating the pair-potentials at the average distances. More precisely, time-averaged interaction energies behave typically smoother in terms of the average distance than the corresponding pair-potentials. This averaging effect is referred to as the thermal smoothing effect. Here, we estimate the strength of the thermal smoothingmore » effect on the Lennard-Jones pair-potential for globular proteins at ambient conditions using x-ray diffraction and simulation data of a representative set of proteins. For specific atom species, we find a significant smoothing effect where the time-averaged interaction energy of a single atom pair can differ by various tens of cal/mol from the Lennard-Jones potential at the average distance. Importantly, we observe a dependency of the effect on the local environment of the involved atoms. The effect is typically weaker for bulky backbone atoms in beta sheets than for side-chain atoms belonging to other secondary structure on the surface of the protein. The results of this work have important practical implications for protein software relying on free energy expressions. We show that the accuracy of free energy expressions can largely be increased by introducing environment specific Lennard-Jones parameters accounting for the fact that the typical thermal motion of protein atoms depends strongly on their local environment.« less

Thermal motion in proteins: Large effects on the time-averaged interaction energies

NASA Astrophysics Data System (ADS)

Goethe, Martin; Fita, Ignacio; Rubi, J. Miguel

2016-03-01

As a consequence of thermal motion, inter-atomic distances in proteins fluctuate strongly around their average values, and hence, also interaction energies (i.e. the pair-potentials evaluated at the fluctuating distances) are not constant in time but exhibit pronounced fluctuations. These fluctuations cause that time-averaged interaction energies do generally not coincide with the energy values obtained by evaluating the pair-potentials at the average distances. More precisely, time-averaged interaction energies behave typically smoother in terms of the average distance than the corresponding pair-potentials. This averaging effect is referred to as the thermal smoothing effect. Here, we estimate the strength of the thermal smoothing effect on the Lennard-Jones pair-potential for globular proteins at ambient conditions using x-ray diffraction and simulation data of a representative set of proteins. For specific atom species, we find a significant smoothing effect where the time-averaged interaction energy of a single atom pair can differ by various tens of cal/mol from the Lennard-Jones potential at the average distance. Importantly, we observe a dependency of the effect on the local environment of the involved atoms. The effect is typically weaker for bulky backbone atoms in beta sheets than for side-chain atoms belonging to other secondary structure on the surface of the protein. The results of this work have important practical implications for protein software relying on free energy expressions. We show that the accuracy of free energy expressions can largely be increased by introducing environment specific Lennard-Jones parameters accounting for the fact that the typical thermal motion of protein atoms depends strongly on their local environment.

[Effect of supervised exercise training on walking speed, claudication distance and quality of life in peripheral arterial disease].

PubMed

Wenkstetten-Holub, Alfa; Kandioler-Honetz, Elisabeth; Kraus, Ingrid; Müller, Rudolf; Kurz, Robert Wolfgang

2012-08-01

Aim of the study was to evaluate the effects of supervised exercise training for peripheral arterial disease (PAD) on walking speed, claudication distance and quality of life. Ninety-four patients in stage IIa/IIb according to Fontaine underwent a six-month exercise training at the Center for Outpatient Rehabilitation Vienna (ZAW). Walking speed and Absolute Claudication Distance (ACD) improved significantly (p < 0,001 and p = 0,007 respectively). Increase of the Initial Claudication Distance (ICD) did not reach statistical significance (p = 0,14). Quality of life, as assessed by the questionnaire "PLC" manifested no significant change. The exercise training achieved considerable effects on walking speed and claudication distance. Despite these improvements, patient's quality of life revealed no relevant change. This outcome could be explained by the fact that aspects of physical functioning relevant to patients with claudicatio intermittens may be underrepresented in the PLC-questionnaire core module.

Implementing Randomised Control Trials in Open and Distance Learning: A Feasibility Study

ERIC Educational Resources Information Center

Herodotou, Christothea; Heiser, Sarah; Rienties, Bart

2017-01-01

Randomised control trials (RCTs) are an evidence-based research approach which has not yet been adopted and widely used in open and distance education to inform educational policy and practice. Despite the challenges entailed in their application, RCTs hold the power to robustly evaluate the effects of educational interventions in distance…

Impact of Target Distance, Target Size, and Visual Acuity on the Video Head Impulse Test.

PubMed

Judge, Paul D; Rodriguez, Amanda I; Barin, Kamran; Janky, Kristen L

2018-05-01

The video head impulse test (vHIT) assesses the vestibulo-ocular reflex. Few have evaluated whether environmental factors or visual acuity influence the vHIT. The purpose of this study was to evaluate the influence of target distance, target size, and visual acuity on vHIT outcomes. Thirty-eight normal controls and 8 subjects with vestibular loss (VL) participated. vHIT was completed at 3 distances and with 3 target sizes. Normal controls were subdivided on the basis of visual acuity. Corrective saccade frequency, corrective saccade amplitude, and gain were tabulated. In the normal control group, there were no significant effects of target size or visual acuity for any vHIT outcome parameters; however, gain increased as target distance decreased. The VL group demonstrated higher corrective saccade frequency and amplitude and lower gain as compared with controls. In conclusion, decreasing target distance increases gain for normal controls but not subjects with VL. Preliminarily, visual acuity does not affect vHIT outcomes.

Logistics of air medical transport: When and where does helicopter transport reduce prehospital time for trauma?

PubMed

Chen, Xilin; Gestring, Mark L; Rosengart, Matthew R; Peitzman, Andrew B; Billiar, Timothy R; Sperry, Jason L; Brown, Joshua B

2018-05-04

Trauma is a time sensitive disease. Helicopter emergency medical services (HEMS) have shown benefit over ground EMS (GEMS), which may be related to reduced prehospital time. The distance at which this time benefit emerges depends on many factors that can vary across regions. Our objective was to determine the threshold distance at which HEMS has shorter prehospital time than GEMS under different conditions. Patients in the PA trauma registry 2000-2013 were included. Distance between zip centroid and trauma center was calculated using straight-line distance for HEMS and driving distance from GIS network analysis for GEMS. Contrast margins from linear regression identified the threshold distance at which HEMS had a significantly lower prehospital time than GEMS, indicated by non-overlapping 95% confidence intervals. The effect of peak traffic times and adverse weather on the threshold distance was evaluated. Geographic effects across EMS regions were also evaluated. A total of 144,741 patients were included with 19% transported by HEMS. Overall, HEMS became faster than GEMS at 7.7miles from the trauma center (p=0.043). HEMS became faster at 6.5miles during peak traffic (p=0.025) compared to 7.9miles during off-peak traffic (p=0.048). Adverse weather increased the distance at which HEMS was faster to 17.1miles (p=0.046) from 7.3miles in clear weather (p=0.036). Significant variation occurred across EMS regions, with threshold distances ranging from 5.4miles to 35.3miles. There was an inverse but non-significant relationship between urban population and threshold distance across EMS regions (ρ -0.351, p=0.28). This is the first study to demonstrate that traffic, weather, and geographic region significantly impact the threshold distance at which HEMS is faster than GEMS. HEMS was faster at shorter distances during peak traffic while adverse weather increased this distance. The threshold distance varied widely across geographic region. These factors must be considered to guide appropriate HEMS triage protocols. III, Therapeutic.

The Evaluation of Foam Performance and Flooding Efficiency

NASA Astrophysics Data System (ADS)

Keliang, Wang; Yuhao, Chen; Gang, Wang; Gen, Li

2017-12-01

ROSS-Miles and spinning drop interfacial tensionmeter are used to select suitable foam system through foam composite index (FCI) and interfacial tension (IT). The selected foam system are taken to conduct further test. The further tests are evaluating the foam system resistance to adsorption with multi-round core flooding dynamic adsorption test and evaluating the performance of foam system with four kinds of different transport distance, quantitatively analyzing the foam system effective distance after dynamic adsorption. The result shows that the foaming ability and the mobilizing ability of the foam system decrease with the increase of the round of dynamic adsorption. As the transport distance increases, the foaming ability and the mobilizing ability of the foam system decrease. This result further reveals the flooding characteristics of nitrogen foam flooding, which provides a reference for the implementation of nitrogen foam flooding technology.

Clinical Evaluation of Reading Performance Using the Salzburg Reading Desk With a Refractive Rotational Asymmetric Multifocal Intraocular Lens.

PubMed

Linz, Katharina; Attia, Mary S A; Khoramnia, Ramin; Tandogan, Tamer; Kretz, Florian T; Auffarth, Gerd Uwe

2016-08-01

To evaluate functional results and reading performance using the Salzburg Reading Desk after implantation of a sector-shaped near-embedded, rotational asymmetrical multifocal intraocular lens (IOL) and a multifocal toric IOL with a +3.00 diopter (D) near addition. In a prospective study, the LentisMplus and Mplus toric IOLs (Oculentis GmbH, Berlin, Germany) were implanted in 34 eyes of 18 patients at the University Eye Hospital of Heidelberg. Uncorrected and corrected distance visual acuity (UDVA, CDVA) and uncorrected and corrected near visual acuity (UNVA, CNVA) were evaluated using standardized visual acuity charts (ETDRS). The Salzburg Reading Desk was used to analyze unilateral and bilateral uncorrected and corrected reading acuity, reading distance, reading speed, and the smallest log-scaled print size that could be read effectively at a set (40 cm/80 cm) and subjective chosen near and intermediate distance. Postoperatively, the median UDVA was 0.08 logMAR (20/25 Snellen) and the median CDVA was 0.01 logMAR (20/20 Snellen). The median UNVA was 0.12 logMAR (20/25 Snellen) and the median CNVA was 0.03 logMAR (20/20 Snellen). The median uncorrected reading acuity measured with the Salzburg Reading Desk for near distance at 40 cm was 0.18 logMAR (20/32 Snellen). The subjectively preferred near distance was 39 cm and revealed similar visual acuity results. The best reading acuity for intermediate distance with a median of 0.22 logMAR (20/32 Snellen) was achieved at a median distance of 62 cm. Reading performance of the multifocal IOL corresponded for near standardized and individual distance, whereas reading function was better at the patient's preferred intermediate distance. [J Refract Surg. 2016;32(8):526-532.]. Copyright 2016, SLACK Incorporated.

Non-flickering 100 m RGB visible light communication transmission based on a CMOS image sensor.

PubMed

Chow, Chi-Wai; Shiu, Ruei-Jie; Liu, Yen-Chun; Liu, Yang; Yeh, Chien-Hung

2018-03-19

We demonstrate a non-flickering 100 m long-distance RGB visible light communication (VLC) transmission based on a complementary-metal-oxide-semiconductor (CMOS) camera. Experimental bit-error rate (BER) measurements under different camera ISO values and different transmission distances are evaluated. Here, we also experimentally reveal that the rolling shutter effect- (RSE) based VLC system cannot work at long distance transmission, and the under-sampled modulation- (USM) based VLC system is a good choice.

Precision and repeatability of the Optotrak 3020 motion measurement system.

PubMed

States, R A; Pappas, E

2006-01-01

Several motion analysis systems are used by researchers to quantify human motion and to perform accurate surgical procedures. The Optotrak 3020 is one of these systems and despite its widespread use there is not any published information on its precision and repeatability. We used a repeated measures design study to evaluate the precision and repeatability of the Optotrak 3020 by measuring distance and angle in three sessions, four distances and three conditions (motion, static vertical, and static tilted). Precision and repeatability were found to be excellent for both angle and distance although they decreased with increasing distance from the sensors and with tilt from the plane of the sensors. Motion did not have a significant effect on the precision of the measurements. In conclusion, the measurement error of the Optotrak is minimal. Further studies are needed to evaluate its precision and repeatability under human motion conditions.

Euclidean distance can identify the mannitol level that produces the most remarkable integral effect on sugarcane micropropagation in temporary immersion bioreactors.

PubMed

Gómez, Daviel; Hernández, L Ázaro; Yabor, Lourdes; Beemster, Gerrit T S; Tebbe, Christoph C; Papenbrock, Jutta; Lorenzo, José Carlos

2018-03-15

Plant scientists usually record several indicators in their abiotic factor experiments. The common statistical management involves univariate analyses. Such analyses generally create a split picture of the effects of experimental treatments since each indicator is addressed independently. The Euclidean distance combined with the information of the control treatment could have potential as an integrating indicator. The Euclidean distance has demonstrated its usefulness in many scientific fields but, as far as we know, it has not yet been employed for plant experimental analyses. To exemplify the use of the Euclidean distance in this field, we performed an experiment focused on the effects of mannitol on sugarcane micropropagation in temporary immersion bioreactors. Five mannitol concentrations were compared: 0, 50, 100, 150 and 200 mM. As dependent variables we recorded shoot multiplication rate, fresh weight, and levels of aldehydes, chlorophylls, carotenoids and phenolics. The statistical protocol which we then carried out integrated all dependent variables to easily identify the mannitol concentration that produced the most remarkable integral effect. Results provided by the Euclidean distance demonstrate a gradually increasing distance from the control in function of increasing mannitol concentrations. 200 mM mannitol caused the most significant alteration of sugarcane biochemistry and physiology under the experimental conditions described here. This treatment showed the longest statistically significant Euclidean distance to the control treatment (2.38). In contrast, 50 and 100 mM mannitol showed the lowest Euclidean distances (0.61 and 0.84, respectively) and thus poor integrated effects of mannitol. The analysis shown here indicates that the use of the Euclidean distance can contribute to establishing a more integrated evaluation of the contrasting mannitol treatments.

Hunting of roe deer and wild boar in Germany: Is non-lead ammunition suitable for hunting?

PubMed

Martin, Annett; Gremse, Carl; Selhorst, Thomas; Bandick, Niels; Müller-Graf, Christine; Greiner, Matthias; Lahrssen-Wiederholt, Monika

2017-01-01

Non-lead hunting ammunition is an alternative to bullets that contain lead. The use of lead ammunition can result in severe contamination of game meat, thus posing a health risk to consumers. With any kind of ammunition for hunting, the terminal effectiveness of bullets is an animal welfare issue. Doubts about the effectiveness of non-lead bullets for a humane kill of game animals in hunting have been discussed. The length of the escape distance after the shot has been used previously as an indicator for bullet performance. The object of this study was to determine how the bullet material (lead or non-lead) influences the observed escape distances. 1,234 records of the shooting of roe deer (Capreolus capreolus) and 825 records of the shooting of wild boar (Sus scrofa) were evaluated. As the bullet material cannot be regarded as the sole cause of variability of escape distances, interactions of other potential influencing variables like shot placement, shooting distance, were analyzed using conditional regression trees and two-part hurdle models. The length of the escape distance is not influenced by the use of lead or non-lead ammunition with either roe deer or wild boar. With roe deer, the length of the escape distance is influenced significantly by the shot placement and the type of hunting. Increasing shooting distances increased the length of the escape distance. With wild boar, shot placement and the age of the animals were found to be a significant influencing factor on the length of the escape distance. The length of the escape distance can be used as an indicator for adequate bullet effectiveness for humane killings of game animals in hunting.Non-lead bullets already exist which have an equally reliable killing effect as lead bullets.

Effect of virtual reality training on walking distance and physical fitness in individuals with Parkinson's disease.

PubMed

de Melo, Gileno Edu Lameira; Kleiner, Ana Francisca Rozin; Lopes, Jamile Benite Palma; Dumont, Arislander Jonathan Lopes; Lazzari, Roberta Delasta; Galli, Manuela; Oliveira, Claudia Santos

2018-04-07

To evaluate the effects of gait training with virtual reality (VR) on walking distance and physical fitness in individuals with Parkinson's Disease (PD). Thirty-seven individuals with PD participated in this prospective, randomized, controlled clinical trial. They were randomly allocated to a control group submitted to conventional training (n = 12), a treadmill group submitted to gait training on a treadmill (n = 13) and a VR group submitted to gait training using the XboxTM (n = 12). Clinical measures, gait variables and the Six-Minute Walk Test (6MWT) were evaluated: pre-intervention, after one intervention session, post-intervention and follow up (30 days after intervention). The VR and treadmill groups travelled longer distances on the 6MWT and had faster gait speed in comparison to the control group. The VR and treadmill groups demonstrated an increase in pre-6MWT HR. The VR group had more intense HR after the first session and throughout training, but these gains were not maintained at the follow-up. The present findings demonstrate that gait training with a VR program is as effective as treadmill training with regard to gains in walking distance and improvements in temporal gait variables in individuals with PD.

An integrated system for dynamic control of auditory perspective in a multichannel sound field

NASA Astrophysics Data System (ADS)

Corey, Jason Andrew

An integrated system providing dynamic control of sound source azimuth, distance and proximity to a room boundary within a simulated acoustic space is proposed for use in multichannel music and film sound production. The system has been investigated, implemented, and psychoacoustically tested within the ITU-R BS.775 recommended five-channel (3/2) loudspeaker layout. The work brings together physical and perceptual models of room simulation to allow dynamic placement of virtual sound sources at any location of a simulated space within the horizontal plane. The control system incorporates a number of modules including simulated room modes, "fuzzy" sources, and tracking early reflections, whose parameters are dynamically changed according to sound source location within the simulated space. The control functions of the basic elements, derived from theories of perception of a source in a real room, have been carefully tuned to provide efficient, effective, and intuitive control of a sound source's perceived location. Seven formal listening tests were conducted to evaluate the effectiveness of the algorithm design choices. The tests evaluated: (1) loudness calibration of multichannel sound images; (2) the effectiveness of distance control; (3) the resolution of distance control provided by the system; (4) the effectiveness of the proposed system when compared to a commercially available multichannel room simulation system in terms of control of source distance and proximity to a room boundary; (5) the role of tracking early reflection patterns on the perception of sound source distance; (6) the role of tracking early reflection patterns on the perception of lateral phantom images. The listening tests confirm the effectiveness of the system for control of perceived sound source distance, proximity to room boundaries, and azimuth, through fine, dynamic adjustment of parameters according to source location. All of the parameters are grouped and controlled together to create a perceptually strong impression of source location and movement within a simulated space.

(Psychological) Distance Makes the Heart Grow Fonder: Effects of Psychological Distance and Relative Intelligence on Men's Attraction to Women.

PubMed

Park, Lora E; Young, Ariana F; Eastwick, Paul W

2015-11-01

Interpersonal attraction may be shaped by (a) one's psychological distance from a target (the subjective experience that a target is close to or far from the self) and (b) the perceived standing of a target on a trait relative to the self (as better or worse than the self). We propose that when evaluating a psychologically distant target, individuals may rely on abstract schemas (e.g., the desirability of a partner's traits) and prefer targets who possess more (vs. less) desirable qualities than themselves. However, when evaluating psychologically near targets, concrete contextual details of the environment (e.g., how a target's behavior affects self-evaluations in the moment) may determine individuals' attraction toward targets. Six studies revealed that when evaluating psychologically distant targets, men showed greater attraction toward women who displayed more (vs. less) intelligence than themselves. In contrast, when targets were psychologically near, men showed less attraction toward women who outsmarted them. © 2015 by the Society for Personality and Social Psychology, Inc.

Complexities in the Evaluation of Distance Education and Virtual Schooling.

ERIC Educational Resources Information Center

Vrasidas, Charalambos; Zembylas, Michalinos; Chamberlain, Richard

2003-01-01

Discusses the issues related to evaluation of distance education and virtual schooling. The evaluation design of a virtual high school project is presented, and goals, stakeholder analysis, evaluator role, data collection, and data analysis are described. The need for evaluation of distance education and the ethical responsibility of the…

Transition State Geometry Measurements from 13C Isotope Effects. The Experimental Transition State for the Epoxidation of Alkenes with Oxaziridines

PubMed Central

Hirschi, Jennifer S.; Takeya, Tetsuya; Hang, Chao; Singleton, Daniel A.

2009-01-01

We suggest here and evaluate a methodology for the measurement of specific interatomic distances from a combination of theoretical calculations and experimentally measured 13C kinetic isotope effects. This process takes advantage of a broad diversity of transition structures available for the epoxidation of 2-methyl-2-butene with oxaziridines. From the isotope effects calculated for these transition structures, a theory-independent relationship between the C-O bond distances of the newly forming bonds and the isotope effects is established. Within the precision of the measurement, this relationship in combination with the experimental isotope effects provides a highly accurate picture of the C-O bonds forming at the transition state. The diversity of transition structures also allows an evaluation of the Schramm process for defining transition state geometries based on calculations at non-stationary points, and the methodology is found to be reasonably accurate. PMID:19146405

Developing and Validation a Usability Evaluation Tools for Distance Education Websites: Persian Version

ERIC Educational Resources Information Center

Hafezi, Soheila; Farahi, Ahmad; Mehri, Soheil Najafi; Mahmoodi, Hosein

2010-01-01

The web is playing a central role in distance education. The word "usability" is usually synonymous with functionality of the system for the user. Also, usability of a website is defined as something that can be used by a specific group of people to carry out specific objectives in an effective way, with efficiency and satisfaction.…

An Exploratory Study of the Effects of Online Course Efficiency Perceptions on Student Evaluation of Teaching (SET) Measures

ERIC Educational Resources Information Center

Estelami, Hooman

2016-01-01

One of the fundamental drivers of the growing use of distance learning methods in modern business education has been the efficiency gains associated with this method of educational delivery. Distance methods benefit both students and educational institutions as they facilitate the processing of large volumes of learning material to overcome…

The visual perception of distance ratios outdoors.

PubMed

Norman, J Farley; Adkins, Olivia C; Dowell, Catherine J; Shain, Lindsey M; Hoyng, Stevie C; Kinnard, Jonathan D

2017-05-01

We conducted an experiment to evaluate the ability of 32 younger and older adults to visually perceive distances in an outdoor setting. On any given trial, the observers viewed 2 environmental distances and were required to estimate the distance ratio-the length of the (usually) larger distance relative to that of the shorter. The stimulus distance ratios ranged from 1.0 (the stimulus distances were identical) to 8.0 (1 distance interval was 8.0 times longer than the other). The stimulus distances were presented within a 26 m × 60 m portion of a grassy field. The observers were able to reliably estimate the stimulus distance ratios: The overall Pearson r correlation coefficient relating the judged and actual distance ratios was 0.762. Fifty-eight percent of the variance in the observers' perceived distance ratios could thus be accounted for by variations in the actual stimulus ratios. About half of the observers significantly underestimated the distance ratios, while the judgments of the remainder were essentially accurate. Significant modulatory effects of sex and age occurred, such that the male observers' judgments were the most precise, while those of the older males were the most accurate.

Distance Education: A Consumer's Guide. What Distance Learners Need To Know.

ERIC Educational Resources Information Center

Western Interstate Commission for Higher Education, Boulder, CO. Western Cooperative for Educational Communications.

This pamphlet is intended to assist the consumer in making informed decisions when choosing between distance learning programs. Distance education and distance learners are defined. Included is advice on beginning a program search; choosing a school; accreditation; evaluating quality of electronically offered programs; evaluate non-accredited…

Seed harvesting by a generalist consumer is context-dependent: Interactive effects across multiple spatial scales

USGS Publications Warehouse

Ostoja, Steven M.; Schupp, Eugene W.; Klinger, Rob

2013-01-01

Granivore foraging decisions affect consumer success and determine the quantity and spatial pattern of seed survival. These decisions are influenced by environmental variation at spatial scales ranging from landscapes to local foraging patches. In a field experiment, the effects of seed patch variation across three spatial scales on seed removal by western harvester ants Pogonomyrmex occidentalis were evaluated. At the largest scale we assessed harvesting in different plant communities, at the intermediate scale we assessed harvesting at different distances from ant mounds, and at the smallest scale we assessed the effects of interactions among seed species in local seed neighborhoods on seed harvesting (i.e. resource–consumer interface). Selected seed species were presented alone (monospecific treatment) and in mixture with Bromus tectorum (cheatgrass; mixture treatment) at four distances from P. occidentalis mounds in adjacent intact sagebrush and non-native cheatgrass-dominated communities in the Great Basin, Utah, USA. Seed species differed in harvest, with B. tectorum being least preferred. Large and intermediate scale variation influenced harvest. More seeds were harvested in sagebrush than in cheatgrass-dominated communities (largest scale), and the quantity of seed harvested varied with distance from mounds (intermediate-scale), although the form of the distance effect differed between plant communities. At the smallest scale, seed neighborhood affected harvest, but the patterns differed among seed species considered. Ants harvested fewer seeds from mixed-seed neighborhoods than from monospecific neighborhoods, suggesting context dependence and potential associational resistance. Further, the effects of plant community and distance from mound on seed harvest in mixtures differed from their effects in monospecific treatments. Beyond the local seed neighborhood, selection of seed resources is better understood by simultaneously evaluating removal at multiple scales. Associational effects provide a useful theoretical basis for better understanding harvester ant foraging decisions. These results demonstrate the importance of ecological context for seed removal, which has implications for seed pools, plant populations and communities.

An Empirical Evaluation of Distance Learning's Effectiveness in the K-12 Setting

ERIC Educational Resources Information Center

Harris-Packer, Jerilyn D.; Ségol, Geneviève

2015-01-01

This study evaluated the effect of online instruction on the academic achievement of K--12 students in ten states as measured by the percentage of proficient students in reading and mathematics at the school level. We used publicly available data provided by the Department of Education in Florida, Michigan, Minnesota, Nevada, Ohio, Pennsylvania,…

Cooperative vigilance: the guanaco's (Lama guanicoe) key antipredator mechanism.

PubMed

Taraborelli, Paula; Gregorio, Pablo; Moreno, Pablo; Novaro, Andrés; Carmanchahi, Pablo

2012-09-01

The concept of sociality has been associated with the effectiveness of antipredator mechanisms, like cooperative vigilance and the dilution effect. Lama guanicoe (guanaco) is a social native herbivore in South America and a social species. The objectives of this study were to evaluate the antipredator responses of different-sized groups of guanacos in areas with varying predation risks and to determine antipredator mechanisms in guanacos. For this, we measured different antipredator responses to a potential predator (human subjects). Detection of predator and flight distances from predator both increased with a greater number of guanacos per group and with greater distances among guanacos within the social group. Both buffer distance and flight time decreased with a greater number of guanacos per group, but increased with greater distances among guanacos inside the social group. Solitary adult males moved shorter distance and mixed groups moved greater distances. Flight distances were greater in areas with tall and dense vegetation than in areas with low vegetation. Buffer distance and flight time were shorter in undulating land than on flat lands, and groups were usually observed on hill slopes. Our results suggest that the benefit of social grouping in guanacos is the increased probability of avoiding predator with cooperative vigilance and not with the dilution effect. This means that a predator could be detected earlier when approaching a guanaco group than when approaching a solitary individuals and could thus be avoided. Copyright © 2012 Elsevier B.V. All rights reserved.

Listening for the Squeaky Wheel: Designing Distance Writing Program Assessment

ERIC Educational Resources Information Center

Tucker, Virginia M.

2012-01-01

Distance writing programs still struggle with assessment strategies that can evaluate student writing as well as their ability to communicate about that writing with peers at a distance. This article uses Kim, Smith and Maeng's 2008 distance education program assessment scheme to evaluate a single distance writing program at Old Dominion…

Clinical Evaluation of Functional Vision of +1.5 Diopters near Addition, Aspheric, Rotational Asymmetric Multifocal Intraocular Lens

PubMed Central

Khoramnia, Rahmin; Attia, Mary Safwat; Koss, Michael Janusz; Linz, Katharina; Auffarth, Gerd Uwe

2016-01-01

Purpose To evaluate postoperative outcomes and visual performance in intermediate distance after implantation of a +1.5 diopters (D) addition, aspheric, rotational asymmetric multifocal intraocular lens (MIOL). Methods Patients underwent bilateral cataract surgery with implantation of an aspheric, asymmetric MIOL with +1.5 D near addition. A complete ophthalmological examination was performed preoperatively and 3 months postoperatively. The main outcome measures were monocular and binocular uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA), distance corrected intermediate visual acuity (DCIVA), uncorrected near visual acuity (UNVA) and distance corrected keratometry, and manifest refraction. The Salzburg Reading Desk was used to analyze unilateral and bilateral functional vision with uncorrected and corrected reading acuity, reading distance, reading speed, and the smallest log-scaled print size that could be read effectively at near and intermediate distances. Results The study comprised 60 eyes of 30 patients (mean age, 68.30 ± 9.26 years; range, 34 to 80 years). There was significant improvement in UDVA and CDVA. Mean UIVA was 0.01 ± 0.09 logarithm of the minimum angle of resolution (logMAR) and mean DCIVA was -0.02 ± 0.11 logMAR. In Salzburg Reading Desk analysis for UIVA, the mean subjective intermediate distance was 67.58 ± 8.59 cm with mean UIVA of -0.02 ± 0.09 logMAR and mean word count of 96.38 ± 28.32 words/min. Conclusions The new aspheric, asymmetric, +1.5 D near addition MIOL offers good results for distance visual function in combination with good performance for intermediate distances and functional results for near distance. PMID:27729759

Clinical Evaluation of Functional Vision of +1.5 Diopters near Addition, Aspheric, Rotational Asymmetric Multifocal Intraocular Lens.

PubMed

Kretz, Florian Tobias Alwin; Khoramnia, Rahmin; Attia, Mary Safwat; Koss, Michael Janusz; Linz, Katharina; Auffarth, Gerd Uwe

2016-10-01

To evaluate postoperative outcomes and visual performance in intermediate distance after implantation of a +1.5 diopters (D) addition, aspheric, rotational asymmetric multifocal intraocular lens (MIOL). Patients underwent bilateral cataract surgery with implantation of an aspheric, asymmetric MIOL with +1.5 D near addition. A complete ophthalmological examination was performed preoperatively and 3 months postoperatively. The main outcome measures were monocular and binocular uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA), distance corrected intermediate visual acuity (DCIVA), uncorrected near visual acuity (UNVA) and distance corrected keratometry, and manifest refraction. The Salzburg Reading Desk was used to analyze unilateral and bilateral functional vision with uncorrected and corrected reading acuity, reading distance, reading speed, and the smallest log-scaled print size that could be read effectively at near and intermediate distances. The study comprised 60 eyes of 30 patients (mean age, 68.30 ± 9.26 years; range, 34 to 80 years). There was significant improvement in UDVA and CDVA. Mean UIVA was 0.01 ± 0.09 logarithm of the minimum angle of resolution (logMAR) and mean DCIVA was -0.02 ± 0.11 logMAR. In Salzburg Reading Desk analysis for UIVA, the mean subjective intermediate distance was 67.58 ± 8.59 cm with mean UIVA of -0.02 ± 0.09 logMAR and mean word count of 96.38 ± 28.32 words/min. The new aspheric, asymmetric, +1.5 D near addition MIOL offers good results for distance visual function in combination with good performance for intermediate distances and functional results for near distance.

Simultaneous minimization of leaf travel distance and tongue-and-groove effect for segmental intensity-modulated radiation therapy.

PubMed

Dai, Jianrong; Que, William

2004-12-07

This paper introduces a method to simultaneously minimize the leaf travel distance and the tongue-and-groove effect for IMRT leaf sequences to be delivered in segmental mode. The basic idea is to add a large enough number of openings through cutting or splitting existing openings for those leaf pairs with openings fewer than the number of segments so that all leaf pairs have the same number of openings. The cutting positions are optimally determined with a simulated annealing technique called adaptive simulated annealing. The optimization goal is set to minimize the weighted summation of the leaf travel distance and tongue-and-groove effect. Its performance was evaluated with 19 beams from three clinical cases; one brain, one head-and-neck and one prostate case. The results show that it can reduce the leaf travel distance and (or) tongue-and-groove effect; the reduction of the leaf travel distance reaches its maximum of about 50% when minimized alone; the reduction of the tongue-and-groove reaches its maximum of about 70% when minimized alone. The maximum reduction in the leaf travel distance translates to a 1 to 2 min reduction in treatment delivery time per fraction, depending on leaf speed. If the method is implemented clinically, it could result in significant savings in treatment delivery time, and also result in significant reduction in the wear-and-tear of MLC mechanics.

[Effect of a surgical mask on six minute walking distance].

PubMed

Person, E; Lemercier, C; Royer, A; Reychler, G

2018-03-01

Six minutes walking test (6MWT) is regularly used in pulmonology. To minimize the risk of cross-infection, some patients must wear surgical mask at rest and sometimes during exercise. To evaluate the effect of wearing a surgical mask during 6MWT in healthy subjects. It is a prospective study on 44 healthy subjects. After a first 6MWT for training, they performed randomly two 6MWT: with or without a surgical mask. Distance and dyspnea, heart rate and saturation variations were recorded. Distance was not modified by the mask (P=0.99). Dyspnea variation was significantly higher with surgical mask (+5.6 vs. +4.6; P<0.001) and the difference was clinically relevant. No difference was found for the variation of other parameters. Wearing a surgical mask modifies significantly and clinically dyspnea without influencing walked distance. Copyright © 2017 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Comparative Analysis of Methods of Evaluating the Lower Ionosphere Parameters by Tweek Atmospherics

NASA Astrophysics Data System (ADS)

Krivonos, A. P.; Shvets, A. V.

2016-12-01

Purpose: A comparative analysis of the phase and frequency methods for determining the Earth-ionosphere effective waveguide heights for the basic and higher types of normal waves (modes) and distance to the source of radiation - lightning - has been made by analyzing pulse signals in the ELF-VLF range - tweek-atmospherics (tweeks). Design/methodology/approach: To test the methods in computer simulations, the tweeks waveforms were synthesized for the Earth-ionosphere waveguide model with the exponential conductivity profile of the lower ionosphere. The calculations were made for a 20-40 dB signal/noise ratio. Findings: The error of the frequency method of determining the effective height of the waveguide for different waveguide modes was less than 0.5 %. The error of the phase method for determining the effective height of the waveguide was less than 0.8 %. Errors in determining the distance to the lightning was less than 1 % for the phase method, and less than 5 % for the frequency method for the source ranges 1000-3000 km. Conclusions: The analysis results have showed the accuracy of the frequency and phase methods being practically the same within distances of 1000-3000 km. For distances less than 1000 km, the phase method shows a more accurate evaluation of the range, so the combination of the two methods can be used to improve estimating the tweek’s propagation path parameters.

Equivalence Testing of Complex Particle Size Distribution Profiles Based on Earth Mover's Distance.

PubMed

Hu, Meng; Jiang, Xiaohui; Absar, Mohammad; Choi, Stephanie; Kozak, Darby; Shen, Meiyu; Weng, Yu-Ting; Zhao, Liang; Lionberger, Robert

2018-04-12

Particle size distribution (PSD) is an important property of particulates in drug products. In the evaluation of generic drug products formulated as suspensions, emulsions, and liposomes, the PSD comparisons between a test product and the branded product can provide useful information regarding in vitro and in vivo performance. Historically, the FDA has recommended the population bioequivalence (PBE) statistical approach to compare the PSD descriptors D50 and SPAN from test and reference products to support product equivalence. In this study, the earth mover's distance (EMD) is proposed as a new metric for comparing PSD particularly when the PSD profile exhibits complex distribution (e.g., multiple peaks) that is not accurately described by the D50 and SPAN descriptor. EMD is a statistical metric that measures the discrepancy (distance) between size distribution profiles without a prior assumption of the distribution. PBE is then adopted to perform statistical test to establish equivalence based on the calculated EMD distances. Simulations show that proposed EMD-based approach is effective in comparing test and reference profiles for equivalence testing and is superior compared to commonly used distance measures, e.g., Euclidean and Kolmogorov-Smirnov distances. The proposed approach was demonstrated by evaluating equivalence of cyclosporine ophthalmic emulsion PSDs that were manufactured under different conditions. Our results show that proposed approach can effectively pass an equivalent product (e.g., reference product against itself) and reject an inequivalent product (e.g., reference product against negative control), thus suggesting its usefulness in supporting bioequivalence determination of a test product to the reference product which both possess multimodal PSDs.

Reliability Based Geometric Design of Horizontal Circular Curves

NASA Astrophysics Data System (ADS)

Rajbongshi, Pabitra; Kalita, Kuldeep

2018-06-01

Geometric design of horizontal circular curve primarily involves with radius of the curve and stopping sight distance at the curve section. Minimum radius is decided based on lateral thrust exerted on the vehicles and the minimum stopping sight distance is provided to maintain the safety in longitudinal direction of vehicles. Available sight distance at site can be regulated by changing the radius and middle ordinate at the curve section. Both radius and sight distance depend on design speed. Speed of vehicles at any road section is a variable parameter and therefore, normally the 98th percentile speed is taken as the design speed. This work presents a probabilistic approach for evaluating stopping sight distance, considering the variability of all input parameters of sight distance. It is observed that the 98th percentile sight distance value is much lower than the sight distance corresponding to 98th percentile speed. The distribution of sight distance parameter is also studied and found to follow a lognormal distribution. Finally, the reliability based design charts are presented for both plain and hill regions, and considering the effect of lateral thrust.

Squared Euclidean distance: a statistical test to evaluate plant community change

Treesearch

Raymond D. Ratliff; Sylvia R. Mori

1993-01-01

The concepts and a procedure for evaluating plant community change using the squared Euclidean distance (SED) resemblance function are described. Analyses are based on the concept that Euclidean distances constitute a sample from a population of distances between sampling units (SUs) for a specific number of times and SUs. With different times, the distances will be...

Hunting of roe deer and wild boar in Germany: Is non-lead ammunition suitable for hunting?

PubMed Central

Gremse, Carl; Selhorst, Thomas; Bandick, Niels; Müller-Graf, Christine; Greiner, Matthias; Lahrssen-Wiederholt, Monika

2017-01-01

Background Non-lead hunting ammunition is an alternative to bullets that contain lead. The use of lead ammunition can result in severe contamination of game meat, thus posing a health risk to consumers. With any kind of ammunition for hunting, the terminal effectiveness of bullets is an animal welfare issue. Doubts about the effectiveness of non-lead bullets for a humane kill of game animals in hunting have been discussed. The length of the escape distance after the shot has been used previously as an indicator for bullet performance. Objective The object of this study was to determine how the bullet material (lead or non-lead) influences the observed escape distances. Methods 1,234 records of the shooting of roe deer (Capreolus capreolus) and 825 records of the shooting of wild boar (Sus scrofa) were evaluated. As the bullet material cannot be regarded as the sole cause of variability of escape distances, interactions of other potential influencing variables like shot placement, shooting distance, were analyzed using conditional regression trees and two-part hurdle models. Results The length of the escape distance is not influenced by the use of lead or non-lead ammunition with either roe deer or wild boar. With roe deer, the length of the escape distance is influenced significantly by the shot placement and the type of hunting. Increasing shooting distances increased the length of the escape distance. With wild boar, shot placement and the age of the animals were found to be a significant influencing factor on the length of the escape distance. Conclusions The length of the escape distance can be used as an indicator for adequate bullet effectiveness for humane killings of game animals in hunting.Non-lead bullets already exist which have an equally reliable killing effect as lead bullets. PMID:28926620

Evaluation of the Effects of Mesoglycan on Some Markers of Endothelial Damage and Walking Distance in Diabetic Patients with Peripheral Arterial Disease.

PubMed

Derosa, Giuseppe; D'Angelo, Angela; Romano, Davide; Maffioli, Pamela

2017-03-06

The aim of this study was to evaluate the variation of some parameters involved in peripheral artery disease progression in diabetic patients with peripheral artery disease after six months of mesoglycan [...].

Use of recorded interactive seminars in orthodontic distance education.

PubMed

Miller, Kenneth T; Hannum, Wallace M; Morley, Tarrl; Proffit, William R

2007-09-01

Our objective was evaluate the effectiveness and acceptability of 3 methods of instructor interaction during distance learning with prerecorded seminars in orthodontic residencies and continuing education. After residents at 3 schools (Sydney, Australia; Winnipeg, Manitoba, Canada; and Manchester, United Kingdom) viewed a recorded interactive seminar, they discussed its content with the seminar leader at a distance via video conferencing, audio-only interaction by telephone, and Internet chat with Net Meeting software (Microsoft, Bellevue, Wash). The residents then completed evaluations containing both closed- and open-ended questions. In addition, attendees at the Iranian Orthodontic Congress also viewed a recorded seminar, had questions answered via an interpreter in a video conference, and completed summary evaluations. Video conferencing received the highest ratings and was never cited as the least favorite method of interaction. Telephone interaction was a close second in mean scores, and Internet chat was a distant third. All residents stated that they would like to be taught through distance education again. However, the Iranian orthodontists were less enthusiastic. Distance learning based on observation of recorded seminars and follow-up interaction is an acceptable method of instruction that can allow residents and practicing orthodontists access to various materials and experts, and perhaps help to ease the strains of current faculty shortages. More data are needed to determine whether video conferencing is worth the additional cost and complexity over audio-only interaction.

The effects of traffic calming measures on pedestrian and motorist behavior

DOT National Transportation Integrated Search

2001-08-01

Traffic calming treatments may benefit pedestrians who are crossing the street by slowing down vehicle traffic, shortening crossing distances, and enhancing motorist and pedestrian visibility. The objective of this study is to evaluate the effects of...

Gravity and antigravity in a brane world with metastable gravitons

NASA Astrophysics Data System (ADS)

Gregory, R.; Rubakov, V. A.; Sibiryakov, S. M.

2000-09-01

In the framework of a five-dimensional three-brane model with quasi-localized gravitons we evaluate metric perturbations induced on the positive tension brane by matter residing thereon. We find that at intermediate distances, the effective four-dimensional theory coincides, up to small corrections, with General Relativity. This is in accord with Csaki, Erlich and Hollowood and in contrast to Dvali, Gabadadze and Porrati. We show, however, that at ultra-large distances this effective four-dimensional theory becomes dramatically different: conventional tensor gravity changes into scalar anti-gravity.

Nuclear Overhauser effect studies on the conformation of magnesium adenosine 5'-triphosphate bound to rabbit muscle creatine kinase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosevear, P.R.; Powers, V.M.; Dowhan, D.

1987-08-25

Nuclear Overhauser effects were used to determine interproton distances on MgATP bound to rabbit muscle creatine kinase. The internuclear distances were used in a distance geometry program that objectively determines both the conformation of the bound MgATP and its uniqueness. Two classes of structures were found that satisfied the measured interproton distances. Both classes had the same anti glycosidic torsional angle (X = 78 +/- 10/sup 0/) but differed in their ribose ring puckers (O1'-endo or C4'-exo). The uniqueness of the glycosidic torsional angle is consistent with the preference of creatine kinase for adenine nucleotides. One of these conformations ofmore » MgATP bound to creatine kinase is indistinguishable from the conformation found for Co(NH/sub 3/)/sub 4/ ATP bound to the catalytic subunit of protein kinase, which also has a high specificity for adenine nucleotides. Distance geometry calculations also suggest that upper limit distances, when low enough (less than or equal to 3.4 A), can be used instead of measured distances to define, within experimental error, the glycosidic torsional angle of bound nucleotides. However, this approach does not permit an evaluation of the ribose ring pucker.« less

Do breeding phase and detection distance influence the effective area surveyed for northern goshawks?

USGS Publications Warehouse

Roberson, A.M.; Andersen, D.E.; Kennedy, P.L.

2005-01-01

Broadcast surveys using conspecific calls are currently the most effective method for detecting northern goshawks (Accipiter gentilis) during the breeding season. These surveys typically use alarm calls during the nestling phase and juvenile food-begging calls during the fledgling-dependency phase. Because goshawks are most vocal during the courtship phase, we hypothesized that this phase would be an effective time to detect goshawks. Our objective was to improve current survey methodology by evaluating the probability of detecting goshawks at active nests in northern Minnesota in 3 breeding phases and at 4 broadcast distances and to determine the effective area surveyed per broadcast station. Unlike previous studies, we broadcast calls at only 1 distance per trial. This approach better quantifies (1) the relationship between distance and probability of detection, and (2) the effective area surveyed (EAS) per broadcast station. We conducted 99 broadcast trials at 14 active breeding areas. When pooled over all distances, detection rates were highest during the courtship (70%) and fledgling-dependency phases (68%). Detection rates were lowest during the nestling phase (28%), when there appeared to be higher variation in likelihood of detecting individuals. EAS per broadcast station was 39.8 ha during courtship and 24.8 ha during fledgling-dependency. Consequently, in northern Minnesota, broadcast stations may be spaced 712m and 562 m apart when conducting systematic surveys during courtship and fledgling-dependency, respectively. We could not calculate EAS for the nestling phase because probability of detection was not a simple function of distance from nest. Calculation of EAS could be applied to other areas where the probability of detection is a known function of distance.

Controlling the perceived distance of an auditory object by manipulation of loudspeaker directivity.

PubMed

Laitinen, Mikko-Ville; Politis, Archontis; Huhtakallio, Ilkka; Pulkki, Ville

2015-06-01

This work presents a method to control the perceived distance of an auditory object by changing the directivity pattern of a loudspeaker and consequently the direct-to-reverberant ratio at the listening spot. Control of the directivity pattern is achieved by beamforming using a compact multi-driver loudspeaker unit. A small-sized cubic array consisting of six drivers is assembled, and per driver beamforming filters are derived from directional measurements of the array. The proposed method is evaluated using formal listening tests. The results show that the perceived distance can be controlled effectively by directivity pattern modification.

A pilot study evaluating alternative approaches of academic detailing in rural family practice clinics

PubMed Central

2012-01-01

Background Academic detailing is an interactive, convenient, and user-friendly approach to delivering non-commercial education to healthcare clinicians. While evidence suggests academic detailing is associated with improvements in prescribing behavior, uncertainty exists about generalizability and scalability in diverse settings. Our study evaluates different models of delivering academic detailing in a rural family medicine setting. Methods We conducted a pilot project to assess the feasibility, effectiveness, and satisfaction with academic detailing delivered face-to-face as compared to a modified approach using distance-learning technology. The recipients were four family medicine clinics within the Oregon Rural Practice-based Research Network (ORPRN). Two clinics were allocated to receive face-to-face detailing and two received outreach through video conferencing or asynchronous web-based outreach. Surveys at midpoint and completion were used to assess effectiveness and satisfaction. Results Each clinic received four outreach visits over an eight month period. Topics included treatment-resistant depression, management of atypical antipsychotics, drugs for insomnia, and benzodiazepine tapering. Overall, 90% of participating clinicians were satisfied with the program. Respondents who received in person detailing reported a higher likelihood of changing their behavior compared to respondents in the distance detailing group for five of seven content areas. While 90%-100% of respondents indicated they would continue to participate if the program were continued, the likelihood of participation declined if only distance approaches were offered. Conclusions We found strong support and satisfaction for the program among participating clinicians. Participants favored in-person approaches to distance interactions. Future efforts will be directed at quantitative methods for evaluating the economic and clinical effectiveness of detailing in rural family practice settings. PMID:23276303

Travel distances by Wisconsin Medicaid enrollees who visit emergency departments for dental care.

PubMed

Okunseri, Christopher; Vanevenhoven, Rabeea; Chelius, Thomas; Beyer, Kirsten M M; Okunseri, Elaye; Lobb, William K; Szabo, Aniko

2016-06-01

Prior studies document increased numbers of nontraumatic dental condition (NTDC) visits to U.S. emergency departments (EDs). However, the influence of travel distance on ED use for NTDCs, particularly for Medicaid enrollees has hitherto received little attention. The authors examined the effect of travel distance on Wisconsin Medicaid enrollees' NTDC visits to EDs after adjustment for covariates. NTDC-related visits claims data for Wisconsin Medicaid (2001-2009) was analyzed. For each enrollee, travel distance to the nearest of 130 EDs in Wisconsin was determined. The number of NTDC visits per person-year was aggregated by ZIP+4 of residence. Negative binomial regression adjusting for the expected number of visits based on race, sex, age of the residents and calendar year was used to evaluate the effect of travel distance, urbanicity, and dentist-population ratio on rate of visits. Enrollees residing in rural counties, entire dental health professional shortage areas, areas with dentist population ratios >20,000: 1 and non-Hispanic Whites travelled the furthest, compared to nearest mean ED distance of 2.9 miles. Enrollees residing 3 miles away or further had significantly lower rates of NTDC visits to EDs. This study demonstrates that distance is a barrier to making NTDC-related visits to EDs. Rates of NTDC visits decreased as travel distance to the nearest ED increased for Medicaid enrollees. © 2016 American Association of Public Health Dentistry.

Evaluation Report of the Course for Distance Education Policy-Makers in Southern Africa. Final Report

ERIC Educational Resources Information Center

Magagula, Cisco

2002-01-01

The evaluator was contracted to determine whether the online or face-to-face course components met course participants' needs and increased their understanding and knowledge of policy development processes, and to determine the efficiency and effectiveness of delivery strategies. In addition, the course evaluator was asked to look at the…

Development and evaluation of a boat-mounted RFID antenna for monitoring freshwater mussels

USGS Publications Warehouse

Fischer, Jesse R.; Neebling, Travis E.; Quist, Michael C.

2012-01-01

Development of radio frequency identification (RFID) technology and passive integrated transponder (PIT) tags has substantially increased the ability of researchers and managers to monitor populations of aquatic organisms. However, use of transportable RFID antenna systems (i.e., backpack-mounted) is currently limited to wadeable aquatic environments (<1.4 m water depth). We describe the design, construction, and evaluation of a boat-mounted RFID antenna to detect individually PIT-tagged benthic aquatic organisms (mussels). We evaluated the effects of tag orientation on detection distances in water with a 32-mm half-duplex PIT tag. Detection distances up to 50 cm from the antenna coils were obtained, but detection distance was dependent on tag orientation. We also evaluated detection distance of PIT tags beneath the sediment to simulate detection of burrowing mussels with 23- and 32-mm tags. In sand substrate, the maximum detection distance varied from 3.5 cm and 4.5 cm (vertical tag orientation) to 24.7 cm and 39.4 cm (45° tag orientation) for the 23- and 32-mm PIT tags, respectively. Our results suggest a 1.4-m total detection width for tagged mussels on the substrate surface by the boat-mounted antenna system regardless of tag orientation. However, burrowed mussels may require multiple passes to increase detection that would be influenced by depth, tag orientation, and tag size. Construction of the boat-mounted antenna was relatively low in cost (<500 USD) and had several advantages (less labor and time intensive, increased safety) over traditional mussel sampling techniques (diving, snorkeling) in nonwadeable habitats.

The effects of landscape position on plant species density: Evidence of past environmental effects in a coastal wetland

USGS Publications Warehouse

Grace, J.B.; Guntenspergen, G.R.

1999-01-01

Here we propose that an important cause of variation in species density may be prior environmental conditions that continue to influence current patterns. In this paper we investigated the degree to which species density varies with location within the landscape, independent of contemporaneous environmental conditions. The area studied was a coastal marsh landscape subject to periodic storm events. To evaluate the impact of historical effects, it was assumed that the landscape position of a plot relative to the river's mouth ('distance from sea') and to the edge of a stream channel ('distance from shore') would correlate with the impact of prior storm events, an assumption supported by previous studies. To evaluate the importance of spatial location on species density, data were collected from five sites located at increasing distances from the river's mouth along the Middle Pearl River in Louisiana. At each site, plots were established systematically along transects perpendicular to the shoreline. For each of the 175 Plots, we measured elevation, soil salinity, percent of plot recently disturbed, percent of sunlight captured by the plant canopy (as a measure of plant abundance), and plant species density. Structural equation analysis ascertained the degree to which landscape position variables explained variation in species density that could not be explained by current environmental indicators. Without considering landscape variables, 54% of the variation in species density could be explained by the effects of salinity, flooding, and plant abundance. When landscape variables were included, distance from shore was unimportant but distance from sea explained an additional 12% of the variance in species density (R2 of final model = 66%). Based on these results it appears that at least some of the otherwise unexplained variation in species density can be attributed to landscape position, and presumably previous storm events. We suggest that future studies may gain additional insight into the factors controlling current patterns of species density by examining the effects of position within the landscape.

The film festival “AUSNAHME|ZUSTAND” (State of Emergency)--do feature films and documentaries on mental health reduce stigma and influence help-seeking attitudes?

PubMed

Conrad, Ines; Schulze, Beate; Corrieri, Sandro; Heider, Dirk; Schomerus, Georg; Riedel-Heller, Steffi G

2014-12-30

The study aims at evaluating the impact of the Germany-wide film festival “AUSNAHME|ZUSTAND” on social distance and help-seeking attitudes of the adolescent audience. The festival, on the subject of mental health, was staged for the second time, aiming to give a podium to the topic mental health and to inform and entertain an adolescent audience that has not been in close contact with the subject before. A pre-post test was carried out to look for the effect of feature films and documentaries on social distance of the audience towards people with mental illness and on the change in help-seeking attitudes. A total of 532 young people with a mean age of 15.6 were questioned during the film festival in Leipzig. As the results show, the effect on the viewers׳ social distance and their help-seeking attitudes strongly depend on the content of the feature films and documentaries. Two films improved attitudes – one both social distance and help-seeking, one only help-seeking. One film increased social distance, and two films did not affect either outcome. Age, gender, and knowing someone with mental health problems also turned out to be decisive factors influencing the development of social distance and help-seeking attitudes. Feature films or documentaries about mental illness can reduce social distance or influence help-seeking attitudes, but effects strongly depend on the particular film.

Sustainable Assessment and Evaluation Strategies for Open and Distance Learning

ERIC Educational Resources Information Center

Okonkwo, Charity Akuadi

2010-01-01

This paper first presents an overview of the concepts of assessment and evaluation in Open and Distance Learning (ODL) environment. The large numbers of students and numerous courses make assessment and evaluation very difficult and administrative nightmare at Distance Learning (DL) institutions. These challenges informed exploring issues relating…

Evaluation of an instructional model to teach clinically relevant medicinal chemistry in a campus and a distance pathway.

PubMed

Alsharif, Naser Z; Galt, Kimberly A

2008-04-15

To evaluate an instructional model for teaching clinically relevant medicinal chemistry. An instructional model that uses Bloom's cognitive and Krathwohl's affective taxonomy, published and tested concepts in teaching medicinal chemistry, and active learning strategies, was introduced in the medicinal chemistry courses for second-professional year (P2) doctor of pharmacy (PharmD) students (campus and distance) in the 2005-2006 academic year. Student learning and the overall effectiveness of the instructional model were assessed. Student performance after introducing the instructional model was compared to that in prior years. Student performance on course examinations improved compared to previous years. Students expressed overall enthusiasm about the course and better understood the value of medicinal chemistry to clinical practice. The explicit integration of the cognitive and affective learning objectives improved student performance, student ability to apply medicinal chemistry to clinical practice, and student attitude towards the discipline. Testing this instructional model provided validation to this theoretical framework. The model is effective for both our campus and distance-students. This instructional model may also have broad-based applications to other science courses.

Comparative evaluation of ultrasound scanner accuracy in distance measurement

NASA Astrophysics Data System (ADS)

Branca, F. P.; Sciuto, S. A.; Scorza, A.

2012-10-01

The aim of the present study is to develop and compare two different automatic methods for accuracy evaluation in ultrasound phantom measurements on B-mode images: both of them give as a result the relative error e between measured distances, performed by 14 brand new ultrasound medical scanners, and nominal distances, among nylon wires embedded in a reference test object. The first method is based on a least squares estimation, while the second one applies the mean value of the same distance evaluated at different locations in ultrasound image (same distance method). Results for both of them are proposed and explained.

An investigation into the effect of surveillance drones on textile evidence at crime scenes.

PubMed

Bucknell, Alistair; Bassindale, Tom

2017-09-01

With increasing numbers of Police forces using drones for crime scene surveillance, the effect of the drones on trace evidence present needs evaluation. In this investigation the effect of flying a quadcopter drone at different heights over a controlled scene and taking off at different distances from the scene were measured. Yarn was placed on a range of floor surfaces and the number lost or moved from their original position was recorded. It was possible to estimate "safe" distances above and take off distance from the bath mat (2m and 1m respectively), and carpet tile (3m and 1m) which were the roughest surfaces. The maximum distances tested of 5m above and 2m from was not far enough to prevent significant disturbance with the other floor surfaces. This report illustrates the importance of considering the impact of new technologies into a forensic workflow on established forensic evidence prior to implementation. Copyright © 2017 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.

Evaluation of Distance Learning in an "Introduction to Biostatistics" Class: A Case Study

ERIC Educational Resources Information Center

Evans, Scott R.; Wang, Rui; Yeh, Tzu-Min; Anderson, Jeff; Haija, Rammy; McBratney-Owen, Paul Madoc; Peeples, Lynne; Sinha, Subir; Xanthakis, Vanessa; Rajicic, Natasa; Zhang, Jiameng

2007-01-01

Biostatistics is not universally available in colleges/universities and is thus an attractive course to offer via distance education. However, evaluation of the impact of distance education on course enrollment and student success is lacking. We evaluated an "Introduction to Biostatistics" course at Harvard University that offered the distance…

Evaluating Quality of Students' Support Services in Open Distance Learning

ERIC Educational Resources Information Center

Nsamba, Asteria; Makoe, Mpine

2017-01-01

Evaluating the quality of students' support services in distance education institutions is vital because by nature Open Distance Learning (ODL) is a high-involvement service industry, with multiple student support service encounters. Most quality evaluation models tend to view quality from the institutional perspective. As a result, little is…

Talker Localization Based on Interference between Transmitted and Reflected Audible Sound

NASA Astrophysics Data System (ADS)

Nakayama, Masato; Nakasako, Noboru; Shinohara, Toshihiro; Uebo, Tetsuji

In many engineering fields, distance to targets is very important. General distance measurement method uses a time delay between transmitted and reflected waves, but it is difficult to estimate the short distance. On the other hand, the method using phase interference to measure the short distance has been known in the field of microwave radar. Therefore, we have proposed the distance estimation method based on interference between transmitted and reflected audible sound, which can measure the distance between microphone and target with one microphone and one loudspeaker. In this paper, we propose talker localization method based on distance estimation using phase interference. We expand the distance estimation method using phase interference into two microphones (microphone array) in order to estimate talker position. The proposed method can estimate talker position by measuring the distance and direction between target and microphone array. In addition, talker's speech is regarded as a noise in the proposed method. Therefore, we also propose combination of the proposed method and CSP (Cross-power Spectrum Phase analysis) method which is one of the DOA (Direction Of Arrival) estimation methods. We evaluated the performance of talker localization in real environments. The experimental result shows the effectiveness of the proposed method.

Test method for telescopes using a point source at a finite distance

NASA Technical Reports Server (NTRS)

Griner, D. B.; Zissa, D. E.; Korsch, D.

1985-01-01

A test method for telescopes that makes use of a focused ring formed by an annular aperture when using a point source at a finite distance is evaluated theoretically and experimentally. The results show that the concept can be applied to near-normal, as well as grazing incidence. It is particularly suited for X-ray telescopes because of their intrinsically narrow annular apertures, and because of the largely reduced diffraction effects.

Examining the Effects of a Behavioural Self-Control Package on the Behaviour of the Distance Learner. REDEAL Research Report #8. Project REDEAL. Research and Evaluation of Distance Education for the Adult Learner.

ERIC Educational Resources Information Center

Powell, Russell; Coldeway, Dan O.

An unsuccessful attempt was made to facilitate study behavior of Athabasca University learners through instruction in behavioral methods of self-control. The general procedure consisted of providing each student with a package containing instructions and materials for the self-application of the strategies of self-monitoring and standard setting.…

An effective visualization technique for depth perception in augmented reality-based surgical navigation.

PubMed

Choi, Hyunseok; Cho, Byunghyun; Masamune, Ken; Hashizume, Makoto; Hong, Jaesung

2016-03-01

Depth perception is a major issue in augmented reality (AR)-based surgical navigation. We propose an AR and virtual reality (VR) switchable visualization system with distance information, and evaluate its performance in a surgical navigation set-up. To improve depth perception, seamless switching from AR to VR was implemented. In addition, the minimum distance between the tip of the surgical tool and the nearest organ was provided in real time. To evaluate the proposed techniques, five physicians and 20 non-medical volunteers participated in experiments. Targeting error, time taken, and numbers of collisions were measured in simulation experiments. There was a statistically significant difference between a simple AR technique and the proposed technique. We confirmed that depth perception in AR could be improved by the proposed seamless switching between AR and VR, and providing an indication of the minimum distance also facilitated the surgical tasks. Copyright © 2015 John Wiley & Sons, Ltd.

Nasolabial Morphology Following Nasoalveolar Molding in Infants With Unilateral Cleft Lip and Palate.

PubMed

Nur Yilmaz, Rahime Burcu; Germeç Çakan, Derya

2018-06-01

The aim of the present study is to evaluate the effects of nasoalveolar molding (NAM) therapy on nasolabial morphology three dimensionally, and compare the nasolabial linear and surface distance measurements in infants with unilateral cleft lip and palate. Facial plaster casts of 42 infants with unilateral cleft lip and palate taken at the onset (pre-NAM) and finishing stage (post-NAM) of NAM were scanned with 3dMDface stereophotogrammetry system (3dMD, Atlanta, GA). Nineteen nasolabial linear and surface distance measurements were performed on three-dimensional images. In addition to standard descriptive statistical calculations (means and SDs), pre- and post-NAM measurements were evaluated by paired t test. All measurements except lip gap, nostril floor width, and nostril diameter increased between pre-NAM and post-NAM. Nostril and lip height increased significantly on the cleft side (P < 0.05). No differences were present between linear and surface distance measurements except for nasal width measurement. Nasal and lip symmetry improved with NAM. The use of surface distance measurements may be advised particularly for continuous and curved anatomic structures in which circumference differences are expected.

Influence of Different Kinds of Music on Walking in Children.

PubMed

Reychler, Gregory; Fabre, Justine; Lux, Amandine; Caty, Gilles; Pieters, Thierry; Liistro, Giuseppe

The aim of this study was to evaluate the effect of different kinds of music on submaximal performance and exercise tolerance in healthy children by means of the 6-minute walking test (6MWT) and to explore the influence of gender. Cross-over study. Ninety-seven children performed 6MWT in four conditions (without music, with their preferred music, with slow and with fast music). Distance, cardio-respiratory parameters, perceived exertion rate, and amount of dyspnea were measured. Walked distance depended on the kind of music (p = .022). To listen to fast music promoted a longer distance when compared with slow music. Walked distance was not influenced by gender (p = .721) and there was no interaction between music and gender for walked distances (p = .069). The other parameters were not modified by music and gender. Music influences submaximal performances without modifying exercise tolerance in healthy children. Music does modify submaximal performance in children.

Self-distancing improves interpersonal perceptions and behavior by decreasing medial prefrontal cortex activity during the provision of criticism.

PubMed

Leitner, Jordan B; Ayduk, Ozlem; Mendoza-Denton, Rodolfo; Magerman, Adam; Amey, Rachel; Kross, Ethan; Forbes, Chad E

2017-04-01

Previous research suggests that people show increased self-referential processing when they provide criticism to others, and that this self-referential processing can have negative effects on interpersonal perceptions and behavior. The current research hypothesized that adopting a self-distanced perspective (i.e. thinking about a situation from a non-first person point of view), as compared with a typical self-immersed perspective (i.e. thinking about a situation from a first-person point of view), would reduce self-referential processing during the provision of criticism, and in turn improve interpersonal perceptions and behavior. We tested this hypothesis in an interracial context since research suggests that self-referential processing plays a role in damaging interracial relations. White participants prepared for mentorship from a self-immersed or self-distanced perspective. They then conveyed negative and positive evaluations to a Black mentee while electroencephalogram (EEG) was recorded. Source analysis revealed that priming a self-distanced (vs self-immersed) perspective predicted decreased activity in regions linked to self-referential processing (medial prefrontal cortex; MPFC) when providing negative evaluations. This decreased MPFC activity during negative evaluations, in turn, predicted verbal feedback that was perceived to be more positive, warm and helpful. Results suggest that self-distancing can improve interpersonal perceptions and behavior by decreasing self-referential processing during the provision of criticism. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Dose-distance metric that predicts late rectal bleeding in patients receiving radical prostate external-beam radiotherapy

NASA Astrophysics Data System (ADS)

Lee, Richard; Chan, Elisa K.; Kosztyla, Robert; Liu, Mitchell; Moiseenko, Vitali

2012-12-01

The relationship between rectal dose distribution and the incidence of late rectal complications following external-beam radiotherapy has been previously studied using dose-volume histograms or dose-surface histograms. However, they do not account for the spatial dose distribution. This study proposes a metric based on both surface dose and distance that can predict the incidence of rectal bleeding in prostate cancer patients treated with radical radiotherapy. One hundred and forty-four patients treated with radical radiotherapy for prostate cancer were prospectively followed to record the incidence of grade ≥2 rectal bleeding. Radiotherapy plans were used to evaluate a dose-distance metric that accounts for the dose and its spatial distribution on the rectal surface, characterized by a logistic weighting function with slope a and inflection point d0. This was compared to the effective dose obtained from dose-surface histograms, characterized by the parameter n which describes sensitivity to hot spots. The log-rank test was used to determine statistically significant (p < 0.05) cut-off values for the dose-distance metric and effective dose that predict for the occurrence of rectal bleeding. For the dose-distance metric, only d0 = 25 and 30 mm combined with a > 5 led to statistical significant cut-offs. For the effective dose metric, only values of n in the range 0.07-0.35 led to statistically significant cut-offs. The proposed dose-distance metric is a predictor of rectal bleeding in prostate cancer patients treated with radiotherapy. Both the dose-distance metric and the effective dose metric indicate that the incidence of grade ≥2 rectal bleeding is sensitive to localized damage to the rectal surface.

Field evaluation of distance-estimation error during wetland-dependent bird surveys

USGS Publications Warehouse

Nadeau, Christopher P.; Conway, Courtney J.

2012-01-01

Context: The most common methods to estimate detection probability during avian point-count surveys involve recording a distance between the survey point and individual birds detected during the survey period. Accurately measuring or estimating distance is an important assumption of these methods; however, this assumption is rarely tested in the context of aural avian point-count surveys. Aims: We expand on recent bird-simulation studies to document the error associated with estimating distance to calling birds in a wetland ecosystem. Methods: We used two approaches to estimate the error associated with five surveyor's distance estimates between the survey point and calling birds, and to determine the factors that affect a surveyor's ability to estimate distance. Key results: We observed biased and imprecise distance estimates when estimating distance to simulated birds in a point-count scenario (x̄error = -9 m, s.d.error = 47 m) and when estimating distances to real birds during field trials (x̄error = 39 m, s.d.error = 79 m). The amount of bias and precision in distance estimates differed among surveyors; surveyors with more training and experience were less biased and more precise when estimating distance to both real and simulated birds. Three environmental factors were important in explaining the error associated with distance estimates, including the measured distance from the bird to the surveyor, the volume of the call and the species of bird. Surveyors tended to make large overestimations to birds close to the survey point, which is an especially serious error in distance sampling. Conclusions: Our results suggest that distance-estimation error is prevalent, but surveyor training may be the easiest way to reduce distance-estimation error. Implications: The present study has demonstrated how relatively simple field trials can be used to estimate the error associated with distance estimates used to estimate detection probability during avian point-count surveys. Evaluating distance-estimation errors will allow investigators to better evaluate the accuracy of avian density and trend estimates. Moreover, investigators who evaluate distance-estimation errors could employ recently developed models to incorporate distance-estimation error into analyses. We encourage further development of such models, including the inclusion of such models into distance-analysis software.

Evaluation of the influence of the internal aqueous solvent structure on electrostatic interactions at the protein-solvent interface by nonlocal continuum electrostatic approach.

PubMed

Rubinstein, Alexander; Sherman, Simon

The dielectric properties of the polar solvent on the protein-solvent interface at small intercharge distances are still poorly explored. To deconvolute this problem and to evaluate the pair-wise electrostatic interaction (PEI) energies of the point charges located at the protein-solvent interface we used a nonlocal (NL) electrostatic approach along with a static NL dielectric response function of water. The influence of the aqueous solvent microstructure (determined by a strong nonelectrostatic correlation effect between water dipoles within the orientational Debye polarization mode) on electrostatic interactions at the interface was studied in our work. It was shown that the PEI energies can be significantly higher than the energies evaluated by the classical (local) consideration, treating water molecules as belonging to the bulk solvent with a high dielectric constant. Our analysis points to the existence of a rather extended, effective low-dielectric interfacial water shell on the protein surface. The main dielectric properties of this shell (effective thickness together with distance- and orientation-dependent dielectric permittivity function) were evaluated. The dramatic role of this shell was demonstrated when estimating the protein association rate constants.

Experimental Evaluation of the Heat Sink Effect in Hepatic Microwave Ablation.

PubMed

Ringe, Kristina I; Lutat, Carolin; Rieder, Christian; Schenk, Andrea; Wacker, Frank; Raatschen, Hans-Juergen

2015-01-01

To demonstrate and quantify the heat sink effect in hepatic microwave ablation (MWA) in a standardized ex vivo model, and to analyze the influence of vessel distance and blood flow on lesion volume and shape. 108 ex vivo MWA procedures were performed in freshly harvested pig livers. Antennas were inserted parallel to non-perfused and perfused (700,1400 ml/min) glass tubes (diameter 5mm) at different distances (10, 15, 20mm). Ablation zones (radius, area) were analyzed and compared (Kruskal-Wallis Test, Dunn's multiple comparison Test). Temperature changes adjacent to the tubes were measured throughout the ablation cycle. Maximum temperature decreased significantly with increasing flow and distance (p<0.05). Compared to non-perfused tubes, ablation zones were significantly deformed by perfused tubes within 15 mm distance to the antenna (p<0.05). At a flow rate of 700 ml/min ablation zone radius was reduced to 37.2% and 80.1% at 10 and 15 mm tube distance, respectively; ablation zone area was reduced to 50.5% and 89.7%, respectively. Significant changes of ablation zones were demonstrated in a pig liver model. Considerable heat sink effect was observed within a diameter of 15 mm around simulated vessels, dependent on flow rate. This has to be taken into account when ablating liver lesions close to vessels.

Observation of Instruction via Distance Learning: The Need for a New Evaluation Paradigm.

ERIC Educational Resources Information Center

Malone, Bobby G.; Malm, Loren D.; Nay, Fred W.; Oliver, Brad E.; Saunders, Nancy G.; Thompson, Jay C.

The evaluation of instruction via distance learning at the high school and college level offers special challenges, particularly the evaluation of one-way video--two-way audio instructional programs. The role of the teacher is radically changed and teaching strategies and course design are particularly important in a distance leaning environment.…

Adaptive Feedback in Local Coordinates for Real-time Vision-Based Motion Control Over Long Distances

NASA Astrophysics Data System (ADS)

Aref, M. M.; Astola, P.; Vihonen, J.; Tabus, I.; Ghabcheloo, R.; Mattila, J.

2018-03-01

We studied the differences in noise-effects, depth-correlated behavior of sensors, and errors caused by mapping between coordinate systems in robotic applications of machine vision. In particular, the highly range-dependent noise densities for semi-unknown object detection were considered. An equation is proposed to adapt estimation rules to dramatic changes of noise over longer distances. This algorithm also benefits the smooth feedback of wheels to overcome variable latencies of visual perception feedback. Experimental evaluation of the integrated system is presented with/without the algorithm to highlight its effectiveness.

Effects of open drainage ditch design on bacterial and fungal communities of cold waterlogged paddy soils

PubMed Central

Qiu, Shanlian; Wang, MK; Wang, Fei; Chen, Jichen; Li, Xiaoyan; Li, Qinghua; Lin, Cheng; Lin, Xinjian

2013-01-01

A field experiment established in 1980 was conducted to evaluate the effects of open drainage ditch applied for water removal on bacterial and fungal communities of cold waterlogged paddy soils in 2011. In this experiment, traditional plate counting and temperature gradient gel electrophoresis were employed to characterize the abundance and diversity of soil bacterial and fungal communities. Four different distances from the open drainage ditch, 5, 15, 25 and 75 m with different degrees of drainage were designed for this study. Maximum populations of culturable aerobic bacteria and fungi were at 15-m distance while minimum populations were at 75-m distance. Significant differences (p < 0.05) in fungal populations were observed at all distances from open drainage ditch. The highest diversity of the bacterial community was found at a distance of 25 m, while that of the fungal community was observed at a distance of 5 m. Sequencing of excised TGGE bands indicated that the dominant bacteria at 75-m distance belonged to anaerobic or microaerobic bacteria. Relationships between microbial characteristics and soil physicochemical properties indicated that soil pH and available nitrogen contents were key factors controlling the abundance of culturable aerobic bacteria and fungi, while soil water capacity also affected the diversity of fungal community. These findings can provide the references for better design and advanced management of the drainage ditches in cold waterlogged paddy soils. PMID:24516468

Modeling interpopulation dispersal by banner-tailed kangaroo rats

USGS Publications Warehouse

Skvarla, J.L.; Nichols, J.D.; Hines, J.E.; Waser, P.M.

2004-01-01

Many metapopulation models assume rules of population connectivity that are implicitly based on what we know about within-population dispersal, but especially for vertebrates, few data exist to assess whether interpopulation dispersal is just within-population dispersal "scaled up." We extended existing multi-stratum mark-release-recapture models to incorporate the robust design, allowing us to compare patterns of within- and between-population movement in the banner-tailed kangaroo rat (Dipodomys spectabilis). Movement was rare among eight populations separated by only a few hundred meters: seven years of twice-annual sampling captured >1200 individuals but only 26 interpopulation dispersers. We developed a program that implemented models with parameters for capture, survival, and interpopulation movement probability and that evaluated competing hypotheses in a model selection framework. We evaluated variants of the island, stepping-stone, and isolation-by-distance models of interpopulation movement, incorporating effects of age, season, and habitat (short or tall grass). For both sexes, QAICc values clearly favored isolation-by-distance models, or models combining the effects of isolation by distance and habitat. Models with probability of dispersal expressed as linear-logistic functions of distance and as negative exponentials of distance fit the data equally well. Interpopulation movement probabilities were similar among sexes (perhaps slightly biased toward females), greater for juveniles than adults (especially for females), and greater before than during the breeding season (especially for females). These patterns resemble those previously described for within-population dispersal in this species, which we interpret as indicating that the same processes initiate both within- and between-population dispersal.

Experimental evaluation of a mathematical model for predicting transfer efficiency of a high volume-low pressure air spray gun.

PubMed

Tan, Y M; Flynn, M R

2000-10-01

The transfer efficiency of a spray-painting gun is defined as the amount of coating applied to the workpiece divided by the amount sprayed. Characterizing this transfer process allows for accurate estimation of the overspray generation rate, which is important for determining a spray painter's exposure to airborne contaminants. This study presents an experimental evaluation of a mathematical model for predicting the transfer efficiency of a high volume-low pressure spray gun. The effects of gun-to-surface distance and nozzle pressure on the agreement between the transfer efficiency measurement and prediction were examined. Wind tunnel studies and non-volatile vacuum pump oil in place of commercial paint were used to determine transfer efficiency at nine gun-to-surface distances and four nozzle pressure levels. The mathematical model successfully predicts transfer efficiency within the uncertainty limits. The least squares regression between measured and predicted transfer efficiency has a slope of 0.83 and an intercept of 0.12 (R2 = 0.98). Two correction factors were determined to improve the mathematical model. At higher nozzle pressure settings, 6.5 psig and 5.5 psig, the correction factor is a function of both gun-to-surface distance and nozzle pressure level. At lower nozzle pressures, 4 psig and 2.75 psig, gun-to-surface distance slightly influences the correction factor, while nozzle pressure has no discernible effect.

Progesterone stimulates the long-distance migration of capacitated ram spermatozoa through viscous media under geotactic condition.

PubMed

Martínez-Rodríguez, Carmen; Anel-López, Luis; Alvarez, Mercedes; Ortega-Ferrusola, Cristina; Boixo, Juan Carlos; Peña, Fernando J; Anel, Luis; de Paz, Paulino

2018-05-15

Forward progressive motility of spermatozoa is an essential prerequisite for reproductive success, and sperm navigation is assisted by guidance mechanisms that may depend on micro-environmental factors. In the present study, we performed an integrated analysis of long-distance ram sperm migration in vitro that combined two environmental factors (10 μM progesterone and a geotactic effect) and the physiological status of the cells (capacitation treatment). A penetration assay was used in which spermatozoa had to travel 20 mm in a viscous medium (two media of differing viscosity: acrylamide and hyaluronic acid) through a tube device. The number of migrating spermatozoa, the physiology of the cells (motility analyzed using a CASA system; acrosomal status, viability and active mitochondria evaluated by flow cytometry; DNA fragmentation index calculated by quantitative PCR) and the morphometry of sperm heads (performed using an image analysis system) were evaluated after long-distance sperm migration. Ram sperm capacitation significantly stimulates cell migration through viscous media under geotactic conditions, and this effect is enhanced by progesterone induction. The rheological characteristics of viscous media have a marked impact on ram sperm migration, and acrylamide more favorably facilitates navigation over a large distance. The migrating spermatozoa are morphologically better adapted (high ellipticity) for displacement in viscous media and exhibit remarkably depleted mitochondrial membrane potential. Copyright © 2018 Elsevier Inc. All rights reserved.

Distance Learning Can Be as Effective as Traditional Learning for Medical Students in the Initial Assessment of Trauma Patients.

PubMed

Farahmand, Shervin; Jalili, Ebrahim; Arbab, Mona; Sedaghat, Mojtaba; Shirazi, Mandana; Keshmiri, Fatemeh; Azizpour, Arsalan; Valadkhani, Somayeh; Bagheri-Hariri, Shahram

2016-09-01

Distance learning is expanding and replacing the traditional academic medical settings. Managing trauma patients seems to be a prerequisite skill for medical students. This study has been done to evaluate the efficiency of distance learning on performing the initial assessment and management in trauma patients, compared with the traditional learning among senior medical students. One hundred and twenty senior medical students enrolled in this single-blind quasi-experimental study and were equally divided into the experimental (distance learning) and control group (traditional learning). All participants did a written MCQ before the study. The control group attended a workshop with a 50-minute lecture on initial management of trauma patients and a case simulation scenario followed by a hands-on session. On the other hand, the experimental group was given a DVD with a similar 50-minute lecture and a case simulation scenario, and they also attended a hands-on session to practice the skills. Both groups were evaluated by a trauma station in an objective structured clinical examination (OSCE) after a month. The performance in the experimental group was statistically better (P=0.001) in OSCE. Distance learning seems to be an appropriate adjunct to traditional learning.

Evaluation of a distance-learning immunology and pathology module in a postgraduate biomedical science course.

PubMed

Ryan, M T; Mulholland, C W

2005-01-01

An electronic presentation of materials for a distance-learning immunology and pathology module from a postgraduate biomedical science course is evaluated. Two different electronic presentation formats for the delivery of the educational material to distance learners are assessed. Responses from users of this material highlighted a preference for a format that has a design tailored to distance learning. There was no significant difference in learning outcome between those taking the module on campus and by distance learning. This suggests that the prerequisites for entry, learning materials and direction given to the students studying by distance learning are adequate for these students to achieve the learning objectives outlined in the course. The evaluation also gave direction for areas within the (CAL) application that can be improved for future students.

Teaching Medical Students at a Distance: Using Distance Learning Benchmarks to Plan and Evaluate a Web-Enhanced Medical Student Curriculum

ERIC Educational Resources Information Center

Olney, Cynthia A.; Chumley, Heidi; Parra, Juan M.

2004-01-01

A team designing a Web-enhanced third-year medical education didactic curriculum based their course planning and evaluation activities on the Institute for Higher Education Policy's (2000) 24 benchmarks for online distance learning. The authors present the team's blueprint for planning and evaluating the Web-enhanced curriculum, which incorporates…

Spatial distribution of an infectious disease in a small mammal community

NASA Astrophysics Data System (ADS)

Correa, Juana P.; Bacigalupo, Antonella; Fontúrbel, Francisco E.; Oda, Esteban; Cattan, Pedro E.; Solari, Aldo; Botto-Mahan, Carezza

2015-10-01

Chagas disease is a zoonosis caused by the parasite Trypanosoma cruzi and transmitted by insect vectors to several mammals, but little is known about its spatial epidemiology. We assessed the spatial distribution of T. cruzi infection in vectors and small mammals to test if mammal infection status is related to the proximity to vector colonies. During four consecutive years we captured and georeferenced the locations of mammal species and colonies of Mepraia spinolai, a restricted-movement vector. Infection status on mammals and vectors was evaluated by molecular techniques. To examine the effect of vector colonies on mammal infection status, we constructed an infection distance index using the distance between the location of each captured mammal to each vector colony and the average T. cruzi prevalence of each vector colony, weighted by the number of colonies assessed. We collected and evaluated T. cruzi infection in 944 mammals and 1976 M. spinolai. We found a significant effect of the infection distance index in explaining their infection status, when considering all mammal species together. By examining the most abundant species separately, we found this effect only for the diurnal and gregarious rodent Octodon degus. Spatially explicit models involving the prevalence and location of infected vectors and hosts had not been reported previously for a wild disease.

Evaluation and monitoring of UVR in Shield Metal ARC Welding processing.

PubMed

Peng, Chiung-yu; Liu, Hung-hsin; Chang, Cheng-ping; Shieh, Jeng-yueh; Lan, Cheng-hang

2007-08-01

This study established a comprehensive approach to monitoring UVR magnitude from Shield Metal Arc Welding (SMAW) processing and quantified the effective exposure based on measured data. The irradiances from welding UVR were calculated with biological effective parameter (Slambda) for human exposure assessment. The spectral weighting function for UVR measurement and evaluation followed the American Conference of Governmental Industrial Hygienists (ACGIH) guidelines. Arc welding processing scatters bright light with UVR emission over the full UV spectrum (UVA, UVB, and UVC). The worst case of effective irradiance from a 50 cm distance arc spot with a 200 A electric current and an electrode E6011 (4 mm) is 311.0 microW cm(-2) and has the maximum allowance time (Tmax) of 9.6 s. Distance is an important factor affecting the irradiance intensity. The worst case of the effective irradiance values from arc welding at 100, 200, and 300 cm distances are 76.2, 16.6, and 12.1 microW cm(-2) with Tmax of 39.4, 180.7, and 247.9 s, respectively. Protective materials (glove and mask) were demonstrated to protect workers from hazardous UVR exposure. From this study, the methodology of UVR monitoring in SMAW processing was developed and established. It is recommended that welders should be fitted with appropriate protective materials for protection from UVR emission hazards.

Monitoring Light Pollution on the Starlight Reserve of Montsec

NASA Astrophysics Data System (ADS)

Ribas, S. J.; Paricio, S.; Canal-Domingo, R.; Gustems, L.; Calvo, C. O.

2015-05-01

Montsec Mountains are a special protected place in Catalonia (NE of Iberian Peninsula). Since 2013 the site has been declared Starlight Reserve and Touristic Destination. In the last three years different projects took place in Montsec to evaluate the quality of night sky and the effects of Light Pollution of nearby (and not so nearby) municipalities. Using SQM techniques in RoadRunner configuration (installed on a car) we have evaluated all the region (1 600 km^2) and we determined the distribution of night sky brightness detecting some excellent areas with values around 21.5--22.0 mags. In addition we have evaluated the effects of the closest big city (Lleida with around 200 000 inhabitants) and we have estimated long distance effects of this city on the natural sky. The effect is detected on zenith up to 25 km away from the city. These data show the critical problem of the long-distance effects of LP on protected areas. To complete the monitoring of the region, a new SQM network is ongoing in cooperation with Parc Astronòmic Montsec and Catalan Service against Light Pollution. During 2014 six SQM permanent detectors are starting their measurements around the area of Montsec and major cities that affects this protected area. This data could be combined with meteorological data (clouds, humidity, etc) in some of the evaluation sites.

Application of distance learning to interactive seminar instruction in orthodontic residency programs.

PubMed

Bednar, Eric D; Hannum, Wallace M; Firestone, Allen; Silveira, Anibal M; Cox, Thomas D; Proffit, William R

2007-11-01

A series of experiments involving 3 orthodontic departments has shown that distance learning can be acceptable to residents and effective in teaching concepts that are fundamental to orthodontic practice. Residents in each department participated in distance seminars, clinical conferences, and clinical seminars via high-speed Internet connections. The acceptability of this form of instruction was judged from evaluation forms completed by the residents. Its effectiveness was judged from pretests and posttests on the seminar topics. The improvement from pretest to posttest scores after observing a sequence of distance seminars was similar to that with direct instruction. Orthodontic residents rated the educational experiences positively. Live participation in seminars via video conferencing was preferred to live observation or later observation of a recording, but observation provided similar improvement in test scores. The acceptability of the distance seminars appeared to be influenced by the instructor's personality and teaching style in facilitating interaction, the seminar subject, the residents' comfort level in dealing with this technology, and the sequence for interaction vs observation. Further development of recorded seminars with live follow-up discussions has the potential to supplement instruction in graduate orthodontic programs and help with the impending shortage of experienced full-time orthodontic faculty.

The effect of proximity to hurricanes Katrina and Rita on subsequent hurricane outlook and optimistic bias.

PubMed

Trumbo, Craig; Lueck, Michelle; Marlatt, Holly; Peek, Lori

2011-12-01

This study evaluated how individuals living on the Gulf Coast perceived hurricane risk after Hurricanes Katrina and Rita. It was hypothesized that hurricane outlook and optimistic bias for hurricane risk would be associated positively with distance from the Katrina-Rita landfall (more optimism at greater distance), controlling for historically based hurricane risk and county population density, demographics, individual hurricane experience, and dispositional optimism. Data were collected in January 2006 through a mail survey sent to 1,375 households in 41 counties on the coast (n = 824, 60% response). The analysis used hierarchal regression to test hypotheses. Hurricane history and population density had no effect on outlook; individuals who were male, older, and with higher household incomes were associated with lower risk perception; individual hurricane experience and personal impacts from Katrina and Rita predicted greater risk perception; greater dispositional optimism predicted more optimistic outlook; distance had a small effect but predicted less optimistic outlook at greater distance (model R(2) = 0.21). The model for optimistic bias had fewer effects: age and community tenure were significant; dispositional optimism had a positive effect on optimistic bias; distance variables were not significant (model R(2) = 0.05). The study shows that an existing measure of hurricane outlook has utility, hurricane outlook appears to be a unique concept from hurricane optimistic bias, and proximity has at most small effects. Future extension of this research will include improved conceptualization and measurement of hurricane risk perception and will bring to focus several concepts involving risk communication. © 2011 Society for Risk Analysis.

Evaluation of an Instructional Model to Teach Clinically Relevant Medicinal Chemistry in a Campus and a Distance Pathway

PubMed Central

Galt, Kimberly A.

2008-01-01

Objectives To evaluate an instructional model for teaching clinically relevant medicinal chemistry. Methods An instructional model that uses Bloom's cognitive and Krathwohl's affective taxonomy, published and tested concepts in teaching medicinal chemistry, and active learning strategies, was introduced in the medicinal chemistry courses for second-professional year (P2) doctor of pharmacy (PharmD) students (campus and distance) in the 2005-2006 academic year. Student learning and the overall effectiveness of the instructional model were assessed. Student performance after introducing the instructional model was compared to that in prior years. Results Student performance on course examinations improved compared to previous years. Students expressed overall enthusiasm about the course and better understood the value of medicinal chemistry to clinical practice. Conclusion The explicit integration of the cognitive and affective learning objectives improved student performance, student ability to apply medicinal chemistry to clinical practice, and student attitude towards the discipline. Testing this instructional model provided validation to this theoretical framework. The model is effective for both our campus and distance-students. This instructional model may also have broad-based applications to other science courses. PMID:18483599

An Evaluative Study of an ICT Module for a School Leadership and Management Preparation Program

ERIC Educational Resources Information Center

Musgrave, Sarietjie; De Wet, Corene

2017-01-01

This study reports on findings of an evaluative study on the effectiveness of an information and communication technology (ICT) module that forms part of the Advanced Certificate in Education: School Leadership and Management program. The study was carried out among distance education (DE) students from the University of the Free State enrolled…

Distance Education in Social Work: An Evaluation of an Undergraduate Course on Family Violence

ERIC Educational Resources Information Center

Walsh, Christine Ann; Baynton, Myra

2012-01-01

Social work is a discipline that emphasizes personal contact and has traditionally been taught face-to-face. This paper examines whether online learning is appropriate for educating social workers about family violence. It describes a newly-developed online course in family violence and evaluates its effectiveness. Two surveys of the class and an…

Distance and protective barrier effects on the composite resin degree of conversion

PubMed Central

Coutinho, Margareth; Trevizam, Natália Carvalho; Takayassu, Renata Nakase; Leme, Ariene Arcas; Soares, Giulliana Panfiglio

2013-01-01

Context: The food wrap films are used to cover the tip of curing light units in order to avoid contamination and prevent damage to the light guide. However, their effects on resin polymerization are not fully known. Aims: We investigated the effects on restoration efficiency of a food wrap protective barrier used on the tip of curing light units. Materials and Methods: For each treatment, five replications were performed, a total of 60 bovine incisor. The degree of conversion (%DC) of restorations with the composite resin Opallis EA2 was evaluated using 3 curing light devices (Optilux 501, Optilight and Ultra LED) and 2 curing distances (0 and 5 mm). The composite resin was tested for restoration of cavities in bovine crowns. %DC values were measured by the Fourier transform infrared spectroscopy-attenuated total reflectance technique. Statistical Analysis Used: The data were analyzed using 3-way ANOVA and Tukey's test. Results: Use of the protective film lowered %DC (F = 4.13; P = 0.05), and the effects of curing distance were associated to the curing light device (F = 3.61; P = 0.03). Conclusions: The distance from the light curing tip and use of a translucent protective barrier on the light-cure device can both impair composite resin %DC. PMID:24015001

Genetic divergence in the common bean (Phaseolus vulgaris L.) in the Cerrado-Pantanal ecotone.

PubMed

da Silva, F A; Corrêa, A M; Teodoro, P E; Lopes, K V; Corrêa, C C G

2017-03-30

Evaluating genetic diversity among genotypes is important for providing parameters for the identification of superior genotypes, because the choice of parents that form segregating populations is crucial. Our objectives were to i) evaluate agronomic performance; ii) compare clustering methods; iii) ascertain the relative contributions of the variables evaluated; and iv) identify the most promising hybrids to produce superior segregating populations. The trial was conducted in 2015 at the State University of Mato Grosso do Sul, Brazil. We used a randomized block design with three replications, and recorded the days to emergence, days to flowering, days to maturity, plant height, number of branches, number of pods, number of seeds per pod, weight of 100 grains, and productivity. The genetic diversity of the genotypes was determined by cluster analysis using two dissimilarity measures: the Euclidean distance and the standardized mean Mahalanobis distance using the Ward hierarchical method. The genotypes 'CNFC 10762', 'IAC Dawn', and 'BRS Style' had the highest grain yields, and clusters that were based on the Euclidean distance differed from those based on the Mahalanobis distance, the second being more precise. The yield grain character has greater relevance to the dispute. Hybrids with a high heterotic effect can be obtained by crossing 'IAC Alvorada' with 'CNFC 10762', 'IAC Alvorada' with 'CNFC 10764', and 'BRS Style' with 'IAC Alvorada'.

38 CFR 4.76 - Visual acuity.

Code of Federal Regulations, 2010 CFR

2010-07-01

... distance and near vision using Snellen's test type or its equivalent. (b) Evaluation of visual acuity. (1) Evaluate central visual acuity on the basis of corrected distance vision with central fixation, even if a central scotoma is present. However, when the lens required to correct distance vision in the poorer eye...

38 CFR 4.76 - Visual acuity.

Code of Federal Regulations, 2011 CFR

2011-07-01

... distance and near vision using Snellen's test type or its equivalent. (b) Evaluation of visual acuity. (1) Evaluate central visual acuity on the basis of corrected distance vision with central fixation, even if a central scotoma is present. However, when the lens required to correct distance vision in the poorer eye...

Pyrotechnic hazards classification and evaluation program test report. Heat flux study of deflagrating pyrotechnic munitions

NASA Technical Reports Server (NTRS)

Fassnacht, P. O.

1971-01-01

A heat flux study of deflagrating pyrotechnic munitions is presented. Three tests were authorized to investigate whether heat flux measurements may be used as effective hazards evaluation criteria to determine safe quantity distances for pyrotechnics. A passive sensor study was conducted simultaneously to investigate their usefulness in recording events and conditions. It was concluded that heat flux measurements can effectively be used to evaluate hazards criteria and that passive sensors are an inexpensive tool to record certain events in the vicinity of deflagrating pyrotechnic stacks.

Alternative information signs : an evaluation of driver comprehension and visual attention.

DOT National Transportation Integrated Search

2015-08-01

The effectiveness of a traffic sign is collectively influenced by the signs understandability, legibility distance, glance legibility, and : learnability; however, understandability has been repeatedly identified as a one of the most important mea...

Arithmetic mismatch negativity and numerical magnitude processing in number matching.

PubMed

Hsu, Yi-Fang; Szücs, Dénes

2011-08-11

This study examined the relationship of the arithmetic mismatch negativity (AMN) and the semantic evaluation of numerical magnitude. The first question was whether the AMN was sensitive to the incongruity in numerical information per se, or rather, to the violation of strategic expectations. The second question was whether the numerical distance effect could appear independently of the AMN. Event-related potentials (ERPs) were recorded while participants decided whether two digits were matching or non-matching in terms of physical similarity. The AMN was enhanced in matching trials presented infrequently relative to non-matching trials presented frequently. The numerical distance effect was found over posterior sites during a 92 ms long interval (236-328 ms) but appeared independently of the AMN. It was not the incongruity in numerical information per se, but rather, the violation of strategic expectations that elicited the AMN. The numerical distance effect might only temporally coincide with the AMN and did not form an inherent part of it.

Experimental Evaluation of the Heat Sink Effect in Hepatic Microwave Ablation

PubMed Central

Ringe, Kristina I.; Lutat, Carolin; Rieder, Christian; Schenk, Andrea; Wacker, Frank; Raatschen, Hans-Juergen

2015-01-01

Purpose To demonstrate and quantify the heat sink effect in hepatic microwave ablation (MWA) in a standardized ex vivo model, and to analyze the influence of vessel distance and blood flow on lesion volume and shape. Materials and Methods 108 ex vivo MWA procedures were performed in freshly harvested pig livers. Antennas were inserted parallel to non-perfused and perfused (700,1400 ml/min) glass tubes (diameter 5mm) at different distances (10, 15, 20mm). Ablation zones (radius, area) were analyzed and compared (Kruskal-Wallis Test, Dunn’s multiple comparison Test). Temperature changes adjacent to the tubes were measured throughout the ablation cycle. Results Maximum temperature decreased significantly with increasing flow and distance (p<0.05). Compared to non-perfused tubes, ablation zones were significantly deformed by perfused tubes within 15mm distance to the antenna (p<0.05). At a flow rate of 700ml/min ablation zone radius was reduced to 37.2% and 80.1% at 10 and 15mm tube distance, respectively; ablation zone area was reduced to 50.5% and 89.7%, respectively. Conclusion Significant changes of ablation zones were demonstrated in a pig liver model. Considerable heat sink effect was observed within a diameter of 15mm around simulated vessels, dependent on flow rate. This has to be taken into account when ablating liver lesions close to vessels. PMID:26222431

Using Pre-test/Post-test Data To Evaluate the Effectiveness of Computer Aided Instruction (A Study of CAI and Its Use with Developmental Reading Students).

ERIC Educational Resources Information Center

Lansford, Carl E.

As computer aided instruction (CAI) and distance learning become more popular, a model for easily evaluating these teaching methods must be developed, one which will enable replication of the study each year. This paper discusses the results of a study using existing dependent and independent variables to evaluate CAI for developmental reading…

Use of a platform in an automated open-field to enhance assessment of anxiety-like behaviors in mice.

PubMed

Pogorelov, Vladimir M; Lanthorn, Thomas H; Savelieva, Katerina V

2007-05-15

The present report describes a setup for simultaneously measuring anxiety-like behaviors and locomotor activity in mice. Animals are placed in a brightly lit, standard automated open-field (OF) in which a rectangular ceramic platform 8 cm high covers one quadrant of the floor. Mice preferred to stay under the platform, avoiding the area with bright illumination. Activities under and outside the platform were measured for 5 min. Chlordiazepoxide and buspirone dose-dependently increased time spent outside the platform (L-Time) and the light distance to total OF distance ratio (L:T-TD) in both genders without changing total OF distance. By contrast, amphetamine decreased L-Time and L:T-TD in males, thus displaying an anxiogenic effect. Imipramine was without selective effect on L-Time or L:T-TD, but decreased total OF distance at the highest dose indicative of a sedative effect. Drug effects were also evaluated in the OF without platform using conventional anxiety measures. Introduction of the platform into the OF apparatus strongly enhanced the sensitivity to anxiolytics. Comparison of strains differing in activity or anxiety levels showed that L-Time and L:T-TD can be used as measures of anxiety-like behavior independent of locomotor activity. Changes in motor activity are reflected in the total distance traveled under and outside the platform. Therefore, the platform test is fully automated, sensitive to both anxiolytic and anxiogenic effects of drugs and genetic phenotypes with little evidence of gender-specific responses, and can be easily utilized by most laboratories measuring behavior.

Enhancing course grades and evaluations using distance education technologies.

PubMed

Carpenter, Roger; Theeke, Laurie; Smothers, Angel

2013-01-01

Delivering appropriate amounts of course content using appropriate methods is a concern for nursing faculty. To address this problem, webcasting, Camtasia, and Wimba Live Classroom were evaluated for impact on course grades and student evaluations in a medical-surgical nursing course. The addition of Camtasia resulted in improved final grades and Student Evaluations of Instruction scores that reflected enhanced critical thinking, teacher effectiveness, and overall learning. Students preferred recorded content that could be viewed on mobile devices.

Long-Distance Interactions Regulate the Structure and Resilience of Coastal Ecosystems

NASA Astrophysics Data System (ADS)

van de Koppel, Johan; van der Heide, Tjisse; Altieri, Andrew H.; Eriksson, Britas Klemens; Bouma, Tjeerd J.; Olff, Han; Silliman, Brian R.

2015-01-01

Mounting evidence indicates that spatial interactions are important in structuring coastal ecosystems. Until recently, however, most of this work has been focused on seemingly exceptional systems that are characterized by regular, self-organized patterns. In this review, we document that interactions that operate at long distances, beyond the direct neighborhood of individual organisms, are more common and have much more far-reaching implications for coastal ecosystems than was previously realized. We review studies from a variety of ecosystem types—including cobble beaches, mussel beds, coral reefs, seagrass meadows, and mangrove forests—that reveal a startling interplay of positive and negative interactions between habitats across distances of up to a kilometer. In addition to classical feeding relations, alterations of physical conditions constitute an important part of these long-distance interactions. This entanglement of habitats has crucial implications for how humans manage coastal ecosystems, and evaluations of anthropogenic impact should explicitly address long-distance and system-wide effects before we deem these human activities to be causing little harm.

Effect of the chest wall on the measurement of hemoglobin concentrations by near-infrared time-resolved spectroscopy in normal breast and cancer.

PubMed

Yoshizawa, Nobuko; Ueda, Yukio; Nasu, Hatsuko; Ogura, Hiroyuki; Ohmae, Etsuko; Yoshimoto, Kenji; Takehara, Yasuo; Yamashita, Yutaka; Sakahara, Harumi

2016-11-01

Optical imaging and spectroscopy using near-infrared light have great potential in the assessment of tumor vasculature. We previously measured hemoglobin concentrations in breast cancer using a near-infrared time-resolved spectroscopy system. The purpose of the present study was to evaluate the effect of the chest wall on the measurement of hemoglobin concentrations in normal breast tissue and cancer. We measured total hemoglobin (tHb) concentration in both cancer and contralateral normal breast using a near-infrared time-resolved spectroscopy system in 24 female patients with breast cancer. Patients were divided into two groups based on menopausal state. The skin-to-chest wall distance was determined using ultrasound images obtained with an ultrasound probe attached to the spectroscopy probe. The apparent tHb concentration of normal breast increased when the skin-to-chest wall distance was less than 20 mm. The tHb concentration in pre-menopausal patients was higher than that in post-menopausal patients. Although the concentration of tHb in cancer tissue was statistically higher than that in normal breast, the contralateral normal breast showed higher tHb concentration than cancer in 9 of 46 datasets. When the curves of tHb concentrations as a function of the skin-to-chest wall distance in normal breast were applied for pre- and post-menopausal patients separately, all the cancer lesions plotted above the curves. The skin-to-chest wall distance affected the measurement of tHb concentration of breast tissue by near-infrared time-resolved spectroscopy. The tHb concentration of breast cancer tissue was more precisely evaluated by considering the skin-to-chest wall distance.

Distance Metric Learning via Iterated Support Vector Machines.

PubMed

Zuo, Wangmeng; Wang, Faqiang; Zhang, David; Lin, Liang; Huang, Yuchi; Meng, Deyu; Zhang, Lei

2017-07-11

Distance metric learning aims to learn from the given training data a valid distance metric, with which the similarity between data samples can be more effectively evaluated for classification. Metric learning is often formulated as a convex or nonconvex optimization problem, while most existing methods are based on customized optimizers and become inefficient for large scale problems. In this paper, we formulate metric learning as a kernel classification problem with the positive semi-definite constraint, and solve it by iterated training of support vector machines (SVMs). The new formulation is easy to implement and efficient in training with the off-the-shelf SVM solvers. Two novel metric learning models, namely Positive-semidefinite Constrained Metric Learning (PCML) and Nonnegative-coefficient Constrained Metric Learning (NCML), are developed. Both PCML and NCML can guarantee the global optimality of their solutions. Experiments are conducted on general classification, face verification and person re-identification to evaluate our methods. Compared with the state-of-the-art approaches, our methods can achieve comparable classification accuracy and are efficient in training.

Evaluation of a Classroom Exercise on Social Distance and Discrimination

ERIC Educational Resources Information Center

Maurer, Trent W.

2013-01-01

This project evaluated a class activity on social distance and discrimination using the Bogardus Social Distance Scale. Students [N = 266] in six sections of a family development course received either lecture or lecture plus the activity and completed two pretest and posttest measures. Results revealed greater positive shifts on the Scale for…

Evaluation of gas well setback policy in the Marcellus Shale region of Pennsylvania in relation to emissions of fine particulate matter.

PubMed

Banan, Zoya; Gernand, Jeremy M

2018-04-18

Shale gas has become an important strategic energy source with considerable potential economic benefits and the potential to reduce greenhouse gas emissions in so far as it displaces coal use. However, there still exist environmental health risks caused by emissions from exploration and production activities. In the United States, states and localities have set different minimum setback policies to reduce the health risks corresponding to the emissions from these locations, but it is unclear whether these policies are sufficient. This study uses a Gaussian plume model to evaluate the probability of exposure exceedance from EPA concentration limits for PM2.5 at various locations around a generic wellsite in the Marcellus shale region. A set of meteorological data monitored at ten different stations across Marcellus shale gas region in Pennsylvania during 2015 serves as an input to this model. Results indicate that even though the current setback distance policy in Pennsylvania (500 ft. or 152.4 m) might be effective in some cases, exposure limit exceedance occurs frequently at this distance with higher than average emission rates and/or greater number of wells per wellpad. Setback distances should be 736 m to ensure compliance with the daily average concentration of PM2.5, and a function of the number of wells to comply with the annual average PM2.5 exposure standard. The Marcellus Shale gas is known as a significant source of criteria pollutants and studies show that the current setback distance in Pennsylvania is not adequate to protect the residents from exceeding the established limits. Even an effective setback distance to meet the annual exposure limit may not be adequate to meet the daily limit. The probability of exceeding the annual limit increases with number of wells per site. We use a probabilistic dispersion model to introduce a technical basis to select appropriate setback distances.

Evaluation of the uncertainties associated with in vivo X-ray fluorescence bone lead calibrations

NASA Astrophysics Data System (ADS)

Lodwick, Jeffrey C.

An anthropometric leg phantom developed at the University of Cincinnati (UC) was used to evaluate the effects that changes in leg position and variation between subjects has on in vivo x-ray fluorescence (XRF) measurements of stable lead in bone. The changes in leg position that were evaluated include changes in source-phantom distance ranging between 0.0 mm and 30.0 mm and phantom rotation over 40 degrees. Source-phantom distance was determined to have a significant effect on XRF measurement results particularly at source-phantom distances greater than 10.0 mm. Rotation of the leg phantom through 40 degrees was determined to have no significant effect on XRF measurement results. Between subject factors that were evaluated include bone calcium content and overlying tissue thickness. Bone calcium content was determined to have a significant effect on XRF measurements when measuring lead in micrograms per gram bone material. However, if measurement results of micrograms of lead per gram calcium (or per gram bone mineral) is used the normalization method makes the change in calcium content not significant. Overlying tissue thickness was determined to have no significant effect on XRF measurement results with tissue thickness ranging between 5.7 and 11.62 mm. The UC leg phantom was modified to include a fibula bone phantom so that the effect that the fibula has on XRF measurement results could be evaluated. The fibula was determined to have no significant effect on XRF measurement results and in the future need not be incorporated into in vivo XRF calibration phantoms. A knee phantom was also developed for purposes of calibrations of in vivo XRF measurement of lead in the patella. XRF measurement results using this phantom were compared to results of XRF measurements made using the plaster-of-Paris (POP) phantoms. A significant difference was observed between the normalized count rates of the two phantom types when either micrograms of lead per gram of bone material or micrograms of lead per gram calcium (bone mineral) is used as the lead content. This difference is consistent with what is observed in real in vivo XRF measurements and indicates the need for the correction factors that are used.

Time-Sharing-Based Synchronization and Performance Evaluation of Color-Independent Visual-MIMO Communication.

PubMed

Kwon, Tae-Ho; Kim, Jai-Eun; Kim, Ki-Doo

2018-05-14

In the field of communication, synchronization is always an important issue. The communication between a light-emitting diode (LED) array (LEA) and a camera is known as visual multiple-input multiple-output (MIMO), for which the data transmitter and receiver must be synchronized for seamless communication. In visual-MIMO, LEDs generally have a faster data rate than the camera. Hence, we propose an effective time-sharing-based synchronization technique with its color-independent characteristics providing the key to overcome this synchronization problem in visual-MIMO communication. We also evaluated the performance of our synchronization technique by varying the distance between the LEA and camera. A graphical analysis is also presented to compare the symbol error rate (SER) at different distances.

Clinical Outcomes after Binocular Implantation of a New Trifocal Diffractive Intraocular Lens

PubMed Central

Kretz, Florian T. A.; Breyer, Detlev; Diakonis, Vasilios F.; Klabe, Karsten; Henke, Franziska; Auffarth, Gerd U.; Kaymak, Hakan

2015-01-01

Purpose. To evaluate visual, refractive, and contrast sensitivity outcomes, as well as the incidence of pseudophakic photic phenomena and patient satisfaction after bilateral diffractive trifocal intraocular lens (IOL) implantation. Methods. This prospective nonrandomized study included consecutive patients undergoing cataract surgery with bilateral implantation of a diffractive trifocal IOL (AT LISA tri 839MP, Carl Zeiss Meditec). Distance, intermediate, and near visual outcomes were evaluated as well as the defocus curve and the refractive outcomes 3 months after surgery. Photopic and mesopic contrast sensitivity, patient satisfaction, and halo perception were also evaluated. Results. Seventy-six eyes of 38 patients were included; 90% of eyes showed a spherical equivalent within ±0.50 diopters 3 months after surgery. All patients had a binocular uncorrected distance visual acuity of 0.00 LogMAR or better and a binocular uncorrected intermediate visual acuity of 0.10 LogMAR or better, 3 months after surgery. Furthermore, 85% of patients achieved a binocular uncorrected near visual acuity of 0.10 LogMAR or better. Conclusions. Trifocal diffractive IOL implantation seems to provide an effective restoration of visual function for far, intermediate, and near distances, providing high levels of visual quality and patient satisfaction. PMID:26301104

Comparison of Bayesian clustering and edge detection methods for inferring boundaries in landscape genetics

USGS Publications Warehouse

Safner, T.; Miller, M.P.; McRae, B.H.; Fortin, M.-J.; Manel, S.

2011-01-01

Recently, techniques available for identifying clusters of individuals or boundaries between clusters using genetic data from natural populations have expanded rapidly. Consequently, there is a need to evaluate these different techniques. We used spatially-explicit simulation models to compare three spatial Bayesian clustering programs and two edge detection methods. Spatially-structured populations were simulated where a continuous population was subdivided by barriers. We evaluated the ability of each method to correctly identify boundary locations while varying: (i) time after divergence, (ii) strength of isolation by distance, (iii) level of genetic diversity, and (iv) amount of gene flow across barriers. To further evaluate the methods' effectiveness to detect genetic clusters in natural populations, we used previously published data on North American pumas and a European shrub. Our results show that with simulated and empirical data, the Bayesian spatial clustering algorithms outperformed direct edge detection methods. All methods incorrectly detected boundaries in the presence of strong patterns of isolation by distance. Based on this finding, we support the application of Bayesian spatial clustering algorithms for boundary detection in empirical datasets, with necessary tests for the influence of isolation by distance. ?? 2011 by the authors; licensee MDPI, Basel, Switzerland.

Evaluation of Cross-Cultural Distance Learning in the Korean ELT Context

ERIC Educational Resources Information Center

Chang, Bok-Myung

2015-01-01

This study aims to review the development of NWCCDL Project during the last 10 years from (2005 to 2014) and evaluate the effects of NWCCDL Project on the students' satisfaction of the project and their affective domain. The research data was analyzed from the results of the questionnaires which were conducted at the end of every semester. This…

A comparative study of inter-abutment distance of dies made from full arch dual-arch impression trays with those made from full arch stock trays: an in vitro study.

PubMed

Reddy, Jagan Mohan; Prashanti, E; Kumar, G Vinay; Suresh Sajjan, M C; Mathew, Xavier

2009-01-01

The dual-arch impression technique is convenient in that it makes the required maxillary and mandibular impressions, as well as the inter-occlusal record in one procedure. The accuracy of inter-abutment distance in dies fabricated from dual-arch impression technique remains in question because there is little information available in the literature. This study was conducted to evaluate the accuracy of inter-abutment distance in dies obtained from full arch dual-arch trays with those obtained from full arch stock metal trays. The metal dual-arch trays showed better accuracy followed by the plastic dual-arch and stock dentulous trays, respectively, though statistically insignificant. The pouring sequence did not have any effect on the inter-abutment distance statistically, though pouring the non-working side of the dual-arch impression first showed better accuracy.

Posterior chamber phakic intraocular lens sizing based on iris pigment layer measurements by anterior segment optical coherence tomography.

PubMed

Malyugin, Boris E; Shpak, Alexander A; Pokrovskiy, Dmitry F

2015-08-01

To use anterior segment optical coherence tomography (AS-OCT) to evaluate the clinical effectiveness of Implantable Collamer Lens posterior chamber phakic intraocular lens (PC pIOL) sizing based on measurement of the distance from the iris pigment end to the iris pigment end. S. Fyodorov Eye Microsurgery Federal State Institution, Moscow, Russia. Evaluation of diagnostic test or technology. Stage 1 was a prospective study. The sulcus-to-sulcus (STS) distance was measured using ultrasound biomicroscopy (UBM) (Vumax 2), and the distance from iris pigment end to iris pigment end was assessed using a proposed AS-OCT algorithm. Part 2 used retrospective data from patients after implantation of a PC pIOL with the size selected according to AS-OCT (Visante) measurements of the distance from iris pigment end to iris pigment end. The PC pIOL vault was measured by AS-OCT, and adverse events were assessed. Stage 1 comprised 32 eyes of 32 myopic patients (mean age 28.4 years ± 6.3 [SD]; mean spherical equivalent [SE] -13.11 ± 4.28 diopters [D]). Stage 2 comprised 29 eyes of 16 patients (mean age 27.7 ± 4.7 years; mean SE -16.55 ± 3.65 D). The mean STS distance (12.35 ± 0.47 mm) was similar to the mean distance from iris pigment end to iris pigment end distance (examiner 1: 12.36 ± 0.51 mm; examiner 2: 12.37 ± 0.53 mm). The PC pIOL sized using the new AS-OCT algorithm had a mean vault of 0.53 ± 0.18 mm and did not produce adverse events during the 12-month follow-up. In 16 of 29 eyes, the PC pIOL vault was within an optimum interval (0.35 to 0.70 mm). The new measurement algorithm can be effectively used for PC pIOL sizing. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Solving the aerodynamics of fungal flight: How air viscosity slows spore motion

PubMed Central

Fischer, Mark W. F.; Stolze-Rybczynski, Jessica L.; Davis, Diana J.; Cui, Yunluan; Money, Nicholas P.

2010-01-01

Viscous drag causes the rapid deceleration of fungal spores after high-speed launches and limits discharge distance. Stokes' law posits a linear relationship between drag force and velocity. It provides an excellent fit to experimental measurements of the terminal velocity of free-falling spores and other instances of low Reynolds number motion (Re<1). More complex, non-linear drag models have been devised for movements characterized by higher Re, but their effectiveness for modeling the launch of fast-moving fungal spores has not been tested. In this paper, we use data on spore discharge processes obtained from ultra-high-speed video recordings to evaluate the effects of air viscosity predicted by Stokes' law and a commonly used non-linear drag model. We find that discharge distances predicted from launch speeds by Stokes' model provide a much better match to measured distances than estimates from the more complex drag model. Stokes' model works better over a wide range projectile sizes, launch speeds, and discharge distances, from microscopic mushroom ballistospores discharged at <1 m/s over a distance of <0.1 mm (Re<1.0), to macroscopic sporangia of Pilobolus that are launched at >10 m/s and travel as far as 2.5 m (Re>100). PMID:21036338

Teaching Teachers through Distance Methods: An Evaluation of a Sri Lankan Programme. Education Division Document, No. 40.

ERIC Educational Resources Information Center

Dock, Alan W.; And Others

This report describes the development process of a distance education program in Sri Lanka run by the Institute of Distance Education for nongraduate teachers inservice, and presents results of the program's evaluation. Two teacher education courses--an elementary education course and a combined science/mathematics course--were offered. The…

Transmission of 51.56-Gb/s OOK signal using 1.55-μm directly modulated laser and duobinary electrical equalizer.

PubMed

Bae, S H; Kim, Hoon; Chung, Y C

2016-10-03

We demonstrate the transmission of 51.56-Gb/s on-off keying (OOK) signals generated by using a 1.55-μm directly modulated laser (DML) over 15-km long standard single-mode fiber. In this experiment, a duobinary electrical equalizer based on a finite-impulse-response filter is used at the receiver to increase the dispersion-limited transmission distance. We evaluate the performances of the 51.56-Gb/s OOK signals with respect to the transmission distance by using the frequency response analysis of the proposed system. This result is used to explain why it is effective to utilize the duobinary equalization (instead of binary equalization) for increasing the transmission distance.

The influence of tyre contact patch and on the stopping distance of automotive vehicles

NASA Astrophysics Data System (ADS)

Selig, M.; Ball, A.; Ash, J.; Schmidt, K.

2012-05-01

This contribution presents the experimental tests results about the influence of the tyre contact patch on the stopping distance of automotive vehicles. The objective of the performed tests is the evaluation of the effect of tyre inflation pressure, hence the resulting tyre contact patch on the braking system and the brake distance. The conditions of the experiment are a dry and level road surface without steering inputs. To record scientific results, a brake robot system is used. The benefit of a robotic system is the elimination of the interfering variable driver, who is not able to apply the brake system at the same time with the same force. State-of-the-art data acquisition tools are used to log the data.

Effects of Special Use Airspace on Economic Benefits of Direct Flights

NASA Technical Reports Server (NTRS)

Datta, Koushik; Barrington, Craig; Foster, John D. (Technical Monitor)

1996-01-01

A methodology for estimating the economic effects of Special Use Airspace (SUA) on direct route flights is presented in this paper. The methodology is based on evaluating operating costs of aircraft and analyzing the different ground-track distances traveled by flights under different air traffic scenarios. Using this methodology the following objectives are evaluated: optimistic bias of studies that assume accessible SUAs the maximum economic benefit of dynamic use of SUAs and the marginal economic benefit of the dynamic use of individual SUAs.

Distance matters: Effect of geographic trauma system resource organization on fatal motor vehicle collisions.

PubMed

Brown, Joshua B; Rosengart, Matthew R; Billiar, Timothy R; Peitzman, Andrew B; Sperry, Jason L

2017-07-01

Trauma systems improve outcome; however, it is unclear how geographic organization of trauma system resources (TSR) affects outcome. Our objective was to evaluate the relationship of fatal motor vehicle collision (MVC) rates and the distance from individual MVC locations to the nearest TSR as a measure of the geographical organization of trauma systems, as well as how theoretical changes in the distribution of TSR may affect fatal MVC rates. All fatal MVC in Pennsylvania 2013-2014 were mapped from the Fatality Analysis Reporting System database. Deaths on scene were excluded. TSR including trauma centers and helicopter bases were mapped. Distance between each fatal MVC and nearest TSR was calculated. The primary outcome was fatal MVC rate per 100 million vehicle miles traveled (VMT). Empiric Bayes kriging and hot spot analysis were performed to evaluate geographic patterns in fatal MVC rates. Association between fatal MVC rate and distance to the nearest TSR was evaluated with linear regression. Spatial lag regression evaluated this association while controlling for MVC and county-level characteristics. We identified 886 fatalities from 863 fatal MVC. Median fatal MVC rate was 0.187 per 100 million VMT. Higher fatal MVC rates and fatality hot spots occur in locations farther from TSR. The fatal MVC rate increased 0.141 per 100 million VMT for every 10 miles farther from the nearest TSR (p < 0.01). When controlling for confounders, the fatal MVC rate increased by 0.089 per 100 million VMT for every 10 miles farther from the nearest TSR (p < 0.01). If two helicopters stationed at trauma centers were relocated into the highest fatality regions, our model predicts a 12.3% relative reduction in the overall MVC fatality rate. Increasing distance to the nearest TSR is associated with increasing fatal MVC rate. The geographic organization of trauma systems may impact outcome, and geospatial analysis can allow data-driven changes to potentially improve outcome. Prognostic/Epidemiologic, level III; Case management, level III.

[Application of locomotor activity test to evaluate functional injury after global cerebral ischemia in C57BL/6 mice].

PubMed

Zhang, Li-quan; Xu, Jia-ni; Wang, Zhen-zhen; Zeng, Li-jun; Ye, Yi-lu; Zhang, Wei-ping; Wei, Er-qing; Zhang, Qi

2014-05-01

To evaluate the application of locomotor activity test in functional injury after global cerebral ischemia (GCI) in C57BL/6 mice. GCI was induced by bilateral carotid arteries occlusion for 30 min in C57BL/6 mice. Mice were divided into sham group, GCI group and minocycline group. Saline or minocycline (45 mg/kg) was i.p. injected once daily for 6 d after ischemia. At Day 6 after ischemia, locomotor activity was recorded for 1 h in open field test. Total distance, central distance, central distance ratio, periphery distance, periphery distance ratio, central time and periphery time were used to evaluate the behavior characteristics of locomotor activity in C57BL/6 mice after ischemia. The survival neuron density was detected by Nissl staining in hippocampus, cortex and striatum. Compared with sham group, total distance, central distance and central time increased and periphery time decreased in C57BL/6 mice after GCI (Ps<0.05). However, minocycline significantly reduced the central distance and central time and increased the periphery time (Ps<0.05). Neurons were damaged in hippocampus, cortex and striatum after GCI, which manifested by decreased neurons and the most serious damage in hippocampal CA1 region. Minocycline significantly improved the neuron appearance and increased the neuron number in hippocampus and striatum (P<0.001 or P<0.05). Locomotor activity in open field test can objectively evaluate the behavior injury after GCI in mice. Central distance and central time can be used as indexes of quantitative assessment.

Quantitative evaluation of deep and shallow tissue layers' contribution to fNIRS signal using multi-distance optodes and independent component analysis.

PubMed

Funane, Tsukasa; Atsumori, Hirokazu; Katura, Takusige; Obata, Akiko N; Sato, Hiroki; Tanikawa, Yukari; Okada, Eiji; Kiguchi, Masashi

2014-01-15

To quantify the effect of absorption changes in the deep tissue (cerebral) and shallow tissue (scalp, skin) layers on functional near-infrared spectroscopy (fNIRS) signals, a method using multi-distance (MD) optodes and independent component analysis (ICA), referred to as the MD-ICA method, is proposed. In previous studies, when the signal from the shallow tissue layer (shallow signal) needs to be eliminated, it was often assumed that the shallow signal had no correlation with the signal from the deep tissue layer (deep signal). In this study, no relationship between the waveforms of deep and shallow signals is assumed, and instead, it is assumed that both signals are linear combinations of multiple signal sources, which allows the inclusion of a "shared component" (such as systemic signals) that is contained in both layers. The method also assumes that the partial optical path length of the shallow layer does not change, whereas that of the deep layer linearly increases along with the increase of the source-detector (S-D) distance. Deep- and shallow-layer contribution ratios of each independent component (IC) are calculated using the dependence of the weight of each IC on the S-D distance. Reconstruction of deep- and shallow-layer signals are performed by the sum of ICs weighted by the deep and shallow contribution ratio. Experimental validation of the principle of this technique was conducted using a dynamic phantom with two absorbing layers. Results showed that our method is effective for evaluating deep-layer contributions even if there are high correlations between deep and shallow signals. Next, we applied the method to fNIRS signals obtained on a human head with 5-, 15-, and 30-mm S-D distances during a verbal fluency task, a verbal working memory task (prefrontal area), a finger tapping task (motor area), and a tetrametric visual checker-board task (occipital area) and then estimated the deep-layer contribution ratio. To evaluate the signal separation performance of our method, we used the correlation coefficients of a laser-Doppler flowmetry (LDF) signal and a nearest 5-mm S-D distance channel signal with the shallow signal. We demonstrated that the shallow signals have a higher temporal correlation with the LDF signals and with the 5-mm S-D distance channel than the deep signals. These results show the MD-ICA method can discriminate between deep and shallow signals. Copyright © 2013 Elsevier Inc. All rights reserved.

[Objective evaluation of arterial intermittent claudication by the walking tolerance test. Comparative study of physiological walking and walking on a conveyor belt (author's transl)].

PubMed

Bouchet, J Y; Franco, A; Morzol, B; Beani, J C

1980-01-01

Two methods are used to evaluate the walking distance: physiological walking along a standard path (0% - 6 mk/h) and walking on a tread mill (10% - 3 km/h). In both tests, four data are checked: -- initial trouble distance, -- cramp or walking-distance, -- localisation of pain, -- recovery time. These tests are dependable for the diagnosis of arterial claudication, reproducible and well tolerated. Their results have been compared: there is no correlation between the initial trouble distance and the cramp distance. However there is a correlation between the cramp distance by physiological walking and on treadmill. Recovery time, if long, is a criteria of gravity. Interests of both methods are discussed.

Two-generation analysis of pollen flow across a landscape. I. Male gamete heterogeneity among females.

PubMed

Smouse, P E; Dyer, R J; Westfall, R D; Sork, V L

2001-02-01

Gene flow is a key factor in the spatial genetic structure in spatially distributed species. Evolutionary biologists interested in microevolutionary processess and conservation biologists interested in the impact of landscape change require a method that measures the real time process of gene movement. We present a novel two-generation (parent-offspring) approach to the study of genetic structure (TwoGener) that allows us to quantify heterogeneity among the male gamete pools sampled by maternal trees scattered across the landscape and to estimate mean pollination distance and effective neighborhood size. First, we describe the model's elements: genetic distance matrices to estimate intergametic distances, molecular analysis of variance to determine whether pollen profiles differ among mothers, and optimal sampling considerations. Second, we evaluate the model's effectiveness by simulating spatially distributed populations. Spatial heterogeneity in male gametes can be estimated by phiFT, a male gametic analogue of Wright's F(ST) and an inverse function of mean pollination distance. We illustrate TwoGener in cases where the male gamete can be categorically or ambiguously determined. This approach does not require the high level of genetic resolution needed by parentage analysis, but the ambiguous case is vulnerable to bias in the absence of adequate genetic resolution. Finally, we apply TwoGener to an empirical study of Quercus alba in Missouri Ozark forests. We find that phiFT = 0.06, translating into about eight effective pollen donors per female and an effective pollination neighborhood as a circle of radius about 17 m. Effective pollen movement in Q. alba is more restricted than previously realized, even though pollen is capable of moving large distances. This case study illustrates that, with a modest investment in field survey and laboratory analysis, the TwoGener approach permits inferences about landscape-level gene movements.

PERMANOVA-S: association test for microbial community composition that accommodates confounders and multiple distances.

PubMed

Tang, Zheng-Zheng; Chen, Guanhua; Alekseyenko, Alexander V

2016-09-01

Recent advances in sequencing technology have made it possible to obtain high-throughput data on the composition of microbial communities and to study the effects of dysbiosis on the human host. Analysis of pairwise intersample distances quantifies the association between the microbiome diversity and covariates of interest (e.g. environmental factors, clinical outcomes, treatment groups). In the design of these analyses, multiple choices for distance metrics are available. Most distance-based methods, however, use a single distance and are underpowered if the distance is poorly chosen. In addition, distance-based tests cannot flexibly handle confounding variables, which can result in excessive false-positive findings. We derive presence-weighted UniFrac to complement the existing UniFrac distances for more powerful detection of the variation in species richness. We develop PERMANOVA-S, a new distance-based method that tests the association of microbiome composition with any covariates of interest. PERMANOVA-S improves the commonly-used Permutation Multivariate Analysis of Variance (PERMANOVA) test by allowing flexible confounder adjustments and ensembling multiple distances. We conducted extensive simulation studies to evaluate the performance of different distances under various patterns of association. Our simulation studies demonstrate that the power of the test relies on how well the selected distance captures the nature of the association. The PERMANOVA-S unified test combines multiple distances and achieves good power regardless of the patterns of the underlying association. We demonstrate the usefulness of our approach by reanalyzing several real microbiome datasets. miProfile software is freely available at https://medschool.vanderbilt.edu/tang-lab/software/miProfile z.tang@vanderbilt.edu or g.chen@vanderbilt.edu Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

PERMANOVA-S: association test for microbial community composition that accommodates confounders and multiple distances

PubMed Central

Tang, Zheng-Zheng; Chen, Guanhua; Alekseyenko, Alexander V.

2016-01-01

Motivation: Recent advances in sequencing technology have made it possible to obtain high-throughput data on the composition of microbial communities and to study the effects of dysbiosis on the human host. Analysis of pairwise intersample distances quantifies the association between the microbiome diversity and covariates of interest (e.g. environmental factors, clinical outcomes, treatment groups). In the design of these analyses, multiple choices for distance metrics are available. Most distance-based methods, however, use a single distance and are underpowered if the distance is poorly chosen. In addition, distance-based tests cannot flexibly handle confounding variables, which can result in excessive false-positive findings. Results: We derive presence-weighted UniFrac to complement the existing UniFrac distances for more powerful detection of the variation in species richness. We develop PERMANOVA-S, a new distance-based method that tests the association of microbiome composition with any covariates of interest. PERMANOVA-S improves the commonly-used Permutation Multivariate Analysis of Variance (PERMANOVA) test by allowing flexible confounder adjustments and ensembling multiple distances. We conducted extensive simulation studies to evaluate the performance of different distances under various patterns of association. Our simulation studies demonstrate that the power of the test relies on how well the selected distance captures the nature of the association. The PERMANOVA-S unified test combines multiple distances and achieves good power regardless of the patterns of the underlying association. We demonstrate the usefulness of our approach by reanalyzing several real microbiome datasets. Availability and Implementation: miProfile software is freely available at https://medschool.vanderbilt.edu/tang-lab/software/miProfile. Contact: z.tang@vanderbilt.edu or g.chen@vanderbilt.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27197815

Intracerebroventricular administration of taurine impairs learning and memory in rats.

PubMed

Ito, Koichi; Arko, Matevž; Kawaguchi, Tomohiro; Kikusui, Takefumi; Kuwahara, Masayoshi; Tsubone, Hirokazu

2012-03-01

Taurine is a semi-essential amino acid widely distributed in the body and we take in it from a wide range of nutritive-tonic drinks to improve health. To date, we have elucidated that oral supplementation of taurine does not affect learning and memory in the rat. However, there are few studies concerning the direct effects of taurine in the brain at the behavior level. In this study, we intracerebroventricularly administered taurine to rats and aimed to elucidate the acute effects on learning and memory using the Morris water maze method. Escape latency, swim distance, and distance to zone, which is the integral of the distance between the rats and the platform for every 0.16 seconds, were adopted as parameters of the ability of learning and memory. We also tried to evaluate the effect of intraperitoneal taurine administration. Escape latency, swim distance, and distance to zone were significantly longer in the intracerebroventricularly taurine-administered rats than in the saline-administered rats. Mean swimming velocity was comparable between these two groups, although the physical performance was improved by taurine administration. Probe trials showed that the manner of the rats in finding the platform was comparable. In contrast, no significant differences were found between the intraperitoneally taurine-administered rats and the saline-administered rats. These results indicate that taurine administered directly into the brain ventricle suppresses and delays the ability of learning and memory in rats. In contrast, it is implied that taurine administered peripherally was not involved in learning and memory.

Definition and feasibility of isolation distances for transgenic maize cultivation.

PubMed

Sanvido, Olivier; Widmer, Franco; Winzeler, Michael; Streit, Bernhard; Szerencsits, Erich; Bigler, Franz

2008-06-01

A major concern related to the adoption of genetically modified (GM) crops in agricultural systems is the possibility of unwanted GM inputs into non-GM crop production systems. Given the increasing commercial cultivation of GM crops in the European Union (EU), there is an urgent need to define measures to prevent mixing of GM with non-GM products during crop production. Cross-fertilization is one of the various mechanisms that could lead to GM-inputs into non-GM crop systems. Isolation distances between GM and non-GM fields are widely accepted to be an effective measure to reduce these inputs. However, the question of adequate isolation distances between GM and non-GM maize is still subject of controversy both amongst scientists and regulators. As several European countries have proposed largely differing isolation distances for maize ranging from 25 to 800 m, there is a need for scientific criteria when using cross-fertilization data of maize to define isolation distances between GM and non-GM maize. We have reviewed existing cross-fertilization studies in maize, established relevant criteria for the evaluation of these studies and applied these criteria to define science-based isolation distances. To keep GM-inputs in the final product well below the 0.9% threshold defined by the EU, isolation distances of 20 m for silage and 50 m for grain maize, respectively, are proposed. An evaluation using statistical data on maize acreage and an aerial photographs assessment of a typical agricultural landscape by means of Geographic Information Systems (GIS) showed that spatial resources would allow applying the defined isolation distances for the cultivation of GM maize in the majority of the cases under actual Swiss agricultural conditions. The here developed approach, using defined criteria to consider the agricultural context of maize cultivation, may be of assistance for the analysis of cross-fertilization data in other countries.

Evaluating the Relationship between FRET Changes and Distance Changes Using DNA Length and Restriction Enzyme Specificity

ERIC Educational Resources Information Center

Pazhani, Yogitha; Horn, Abigail E.; Grado, Lizbeth; Kugel, Jennifer F.

2016-01-01

FRET (Fo¨rster resonance energy transfer) involves the transfer of energy from an excited donor fluorophore to an acceptor molecule in a manner that is dependent on the distance between the two. A biochemistry laboratory experiment is described that teaches students how to use FRET to evaluate distance changes in biological molecules. Students…

The Evaluations of the College Students' Perceptions on Distance Education from the Point of the Technical and Educational Factors

ERIC Educational Resources Information Center

Gok, Tolga

2015-01-01

The purpose of the research was to investigate the college students' opinions about distance education courses. The distance education questionnaire (DEQ) was developed for evaluating the perceptions of the students. The DEQ was conducted on 66 college students enrolled in the compulsory courses. The DEQ consisted of 18 items and two factors…

Impact of travel distance to the treatment facility on overall mortality in US patients with prostate cancer.

PubMed

Vetterlein, Malte W; Löppenberg, Björn; Karabon, Patrick; Dalela, Deepansh; Jindal, Tarun; Sood, Akshay; Chun, Felix K-H; Trinh, Quoc-Dien; Menon, Mani; Abdollah, Firas

2017-09-01

The objective of this study was to investigate the impact of travel distance to the treating facility on the risk of overall mortality (OM) among US patients with prostate cancer (PCa). In total, 775,999 patients who had PCa in all stages and received treatment with different strategies (radical prostatectomy, radiation therapy, observation, androgen-deprivation therapy, multimodal treatment, and chemotherapy) were drawn from the National Cancer Data Base from 2004 through 2012. Independent predictors of travel distance (intermediate [12.5-49.9 miles] and long [49.9-249.9 miles] vs short[<12.5 miles]) and its effect on OM were calculated using multivariable regression analyses. Additional analyses evaluated the distance effect on OM in selected subgroups. In total, 54.5%, 33.4%, and 12.1% of patients traveled short, intermediate, and long distances, respectively. Residency in rural areas and the receipt of treatment at academic/high-volume centers independently predicted long travel distance. Non-Hispanic black men and Medicaid-insured men were less likely to travel long distances (all P < .001). Overall, traveling a long distance (hazard ratio, 0.87; 95% confidence interval, 0.83-0.92; P < .001) was associated with lower OM risk compared with traveling a short distance. This held true among non-Hispanic white men; privately insured and Medicare-insured men; those who underwent radical prostatectomy, received radiation therapy, and received multimodal strategies; and those who received treatment at academic/high-volume centers (P < .01), but not among non-Hispanic black men (P = .3). Long travel distance was associated with an increased OM in Medicaid-insured patients (P < .001). An OM benefit was observed among men who traveled long distances for PCa treatment, which is likely to be a reflection of centralization of care and more favorable patient-level characteristics in those travelers. Furthermore, the survival benefit mediated by long travel distances appears to be influenced by baseline socioeconomic, treatment, and facility-level factors. Cancer 2017;123:3241-52. © 2017 American Cancer Society. © 2017 American Cancer Society.

Evaluation of Dynamic Passing Sight Distance Problem Using a Finite Element Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Xuedong; Radwan, Essam; Zhang, Fan

2008-06-01

Sufficient passing sight distance is an important control for two-lane rural highway design to minimize the possibility of a head-on collision between passing and opposing vehicles. Traditionally, passing zones are marked by checking passing sight distance that is potentially restricted by static sight obstructions. Such obstructions include crest curves, overpasses, and lateral objects along highways. This paper proposes a new concept of dynamic sight-distance assessment, which involves restricted passing sight distances due to the impeding vehicles that are traveling in the same direction. Using a finite-element model, the dynamic passing sight-distance problem was evaluated, and the writers analyzed the relationshipsmore » between the available passing sight distance and other factors such as the horizontal curve radius, impeding vehicle dimensions, and a driver s following distance. It was found that the impeding vehicles may cause substantially insufficient passing sight distances, which may lead to potential traffic safety problems. It is worthwhile to expand on this safety issue and consider the dynamic passing sight distance in highway design.« less

Evaluation of the effectiveness of child safety restraints

DOT National Transportation Integrated Search

1987-03-01

The goals of the study were to better establish the relationsips between proper and improper usage of safety seats in crashes and the resulting injury levels and mechanisms and to establish measures of the distance from home that the children were wh...

Dynamic feet distance: A new functional assessment during treadmill locomotion in normal and thoracic spinal cord injured rats.

PubMed

Diogo, Camila Cardoso; Costa, Luís Maltez da; Pereira, José Eduardo; Filipe, Vítor; Couto, Pedro Alexandre; Magalhães, Luís G; Geuna, Stefano; Armada-da-Silva, Paulo A; Maurício, Ana Colette; Varejão, Artur Severo

2017-09-29

Of all the detrimental effects of spinal cord injury (SCI), one of the most devastating is the disruption of the ability to perform functional movement. Very little is known on the recovery of hindlimb joint kinematics after clinically-relevant contusive thoracic lesion in experimental animal models. A new functional assessment instrument, the dynamic feet distance (DFD) was used to describe the distance between the two feet throughout the gait cycle in normal and affected rodents. The purpose of this investigation was the evaluation and characterization of the DFD during treadmill locomotion in normal and T9 contusion injured rats, using three-dimensional (3D) instrumented gait analysis. Despite that normal and injured rats showed a similar pattern in the fifth metatarsal head joints distance excursion, we found a significantly wider distance between the feet during the entire gait cycle following spinal injury. This is the first study to quantify the distance between the two feet, throughout the gait cycle, and the biomechanical adjustments made between limbs in laboratory rodents after nervous system injury. Copyright © 2017 Elsevier B.V. All rights reserved.

Active commuting to school in Finland, the potential for physical activity increase in different seasons

PubMed Central

Kallio, Jouni; Turpeinen, Salla; Hakonen, Harto; Tammelin, Tuija

2016-01-01

Background Active commuting to school (ACS) can be a significant source of physical activity and provide many health benefits. Objective This study identified the potential to increase physical activity levels by promoting ACS in Finnish schools and evaluated the effects of season, distance and age on ACS. Design Data were collected with a questionnaire from 5,107 students, aged 10–16, in 45 comprehensive schools in Finland. The distance and the mode of transport to school in different seasons were self-reported. Results The prevalence of ACS was over 80% during spring/fall for those living 0–5 km from school. ACS was inversely associated with the distance to school and was lower in winter compared to spring and fall. Cycling is less common in winter, especially among girls and younger students. The potential for increasing students’ physical activity levels via ACS seems to be largest in winter, especially among students living 1–5 km from school. The variation in the prevalence of ACS between schools was large, especially in winter. Conclusions When planning interventions to promote ACS, one is encouraged to acknowledge and evaluate the potential in the selected target schools in different seasons. The potential varies largely between schools and seasons and is highly dependent on students’ commuting distances. PMID:27924739

Development of microarray device for functional evaluation of PC12D cell axonal extension ability

NASA Astrophysics Data System (ADS)

Nakamachi, Eiji; Yanagimoto, Junpei; Murakami, Shinya; Morita, Yusuke

2014-04-01

In this study, we developed a microarray bio-MEMS device that could trap PC12D (rat pheochromocytoma cells) cells to examine the intercellular interaction effect on the cell activation and the axonal extension ability. This is needed to assign particular patterns of PC12D cells to establish a cell functional evaluation technique. This experimental observation-based technique can be used for design of the cell sheet and scaffold for peripheral and central nerve regeneration. We have fabricated a micropillar-array bio-MEMS device, whose diameter was approximately 10 μm, by using thick photoresist SU-8 on the glass slide substrate. A maximum trapped PC12D cell ratio, 48.5%, was achieved. Through experimental observation of patterned PC12D "bi-cells" activation, we obtained the following results. Most of the PC12D "bi-cells" which had distances between 40 and 100 μm were connected after 24 h with a high probability. On the other hand, "bi-cells" which had distances between 110 and 200 μm were not connected. In addition, we measured axonal extension velocities in cases where the intercellular distance was between 40 and 100 μm. A maximum axonal extension velocity, 86.4 μm/h, was obtained at the intercellular distance of 40 μm.

Neighborhood educational disparities in active commuting among women: the effect of distance between the place of residence and the place of work/study (an ACTI-Cités study).

PubMed

Perchoux, Camille; Nazare, Julie-Anne; Benmarhnia, Tarik; Salze, Paul; Feuillet, Thierry; Hercberg, Serge; Hess, Franck; Menai, Mehdi; Weber, Christiane; Charreire, Hélène; Enaux, Christophe; Oppert, Jean-Michel; Simon, Chantal

2017-06-12

Active transportation has been associated with favorable health outcomes. Previous research highlighted the influence of neighborhood educational level on active transportation. However, little is known regarding the effect of commuting distance on social disparities in active commuting. In this regard, women have been poorly studied. The objective of this paper was to evaluate the relationship between neighborhood educational level and active commuting, and to assess whether the commuting distance modifies this relationship in adult women. This cross-sectional study is based on a subsample of women from the Nutrinet-Santé web-cohort (N = 1169). Binomial, log-binomial and negative binomial regressions were used to assess the associations between neighborhood education level and (i) the likelihood of reporting any active commuting time, and (ii) the share of commuting time made by active transportation modes. Potential effect measure modification of distance to work on the previous associations was assessed both on the additive and the multiplicative scales. Neighborhood education level was positively associated with the probability of reporting any active commuting time (relative risk = 1.774; p < 0.05) and the share of commuting time spent active (relative risk = 1.423; p < 0.05). The impact of neighborhood education was greater at long distances to work for both outcomes. Our results suggest that neighborhood educational disparities in active commuting tend to increase with commuting distance among women. Further research is needed to provide geographically driven guidance for health promotion intervention aiming at reducing disparities in active transportation among socioeconomic groups.

Evaluation in Distance Teaching. Proceedings of a Workshop (Townsville, Australia, May 11-14, 1980).

ERIC Educational Resources Information Center

Armstrong, John D., Ed.; Store, Ron E., Ed.

Proceedings of a 1980 workshop in Queensland, Australia, on evaluation in distance teaching are presented. Two focal areas were the assessment of students and evaluation of programs and courses. In addition to keynote and workshop papers, a variety of evaluation forms are presented. Among the papers and authors are: "The Setting of Tertiary…

Effects of irradiation distance on supply of reactive oxygen species to the bottom of a Petri dish filled with liquid by an atmospheric O{sub 2}/He plasma jet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kawasaki, Toshiyuki, E-mail: kawasaki@nbu.ac.jp; Kusumegi, Shota; Kudo, Akihiro

The impact of irradiation distances on plasma jet-induced specific effects on the supply of reactive oxygen species (ROS) to the bottom of a Petri dish filled with liquid was investigated using a KI-starch gel reagent that can be employed as a ROS indicator even in water. O{sub 3} exposure experiments without plasma irradiation were also performed to elucidate the specific effects of the plasma jet. Relative concentrations of ROS transported to the bottom were evaluated using absorbance measurements. The results indicated that ROS supply to the bottom is markedly enhanced by the plasma jet irradiation at shorter irradiation distances, whereasmore » similar results could not be obtained for the O{sub 3} exposure. In these cases, the liquid mixing in the depth direction was also enhanced by the plasma jet irradiation only, and the supply of reactive atomic oxygen to the liquid surface was markedly increased as well.« less

Surface modification of carbon nanotubes using 3-aminopropyltriethoxysilane to improve mechanical properties of nanocomposite based polymer matrix: Experimental and Density functional theory study

NASA Astrophysics Data System (ADS)

Hamed Mashhadzadeh, A.; Fereidoon, Ab.; Ghorbanzadeh Ahangari, M.

2017-10-01

In current study we combined theoretical and experimental studies to evaluate the effect of functionalization and silanization on mechanical behavior of polymer-based/CNT nanocomposites. Epoxy was selected as thermoset polymer, polypropylene and poly vinyl chloride were selected as thermoplastic polymers. The whole procedure is divided to two sections . At first we applied density functional theory (DFT) to analyze the effect of functionalization on equilibrium distance and adsorption energy of unmodified, functionalized by sbnd OH group and silanized epoxy/CNT, PP/CNT and PVC/CNT nanocomposites and the results showed that functionalization increased adsorption energy and reduced the equilibrium distance in all studied nanocomposites and silanization had higher effect comparing to OH functionalizing. Then we prepared experimental samples of all mentioned nanocomposites and tested their tensile and flexural strength properties. The obtained results showed that functionalization increased the studied mechanical properties in all evaluated nanocomposites. Finally we compared the results of experimental and theoretical sections with each other and estimated a suitable agreement between these parts.

Learning at a Distance in South Dakota: Description and Evaluation of the Diffusion of a Distance Education.

ERIC Educational Resources Information Center

Simonson, Michael; Bauck, Tamara

One major component of the efforts to promote the use of technology and distance education in South Dakota and specifically of Phase III of the Connecting the Schools Project-an initiative announced in the spring of 1999 by Governor Janklow that built a statewide intranet among all 176 school districts--was a comprehensive evaluation activity. The…

Correction of Motion Artifacts From Shuttle Mode Computed Tomography Acquisitions for Body Perfusion Imaging Applications.

PubMed

Ghosh, Payel; Chandler, Adam G; Altinmakas, Emre; Rong, John; Ng, Chaan S

2016-01-01

The aim of this study was to investigate the feasibility of shuttle-mode computed tomography (CT) technology for body perfusion applications by quantitatively assessing and correcting motion artifacts. Noncontrast shuttle-mode CT scans (10 phases, 2 nonoverlapping bed locations) were acquired from 4 patients on a GE 750HD CT scanner. Shuttling effects were quantified using Euclidean distances (between-phase and between-bed locations) of corresponding fiducial points on the shuttle and reference phase scans (prior to shuttle mode). Motion correction with nonrigid registration was evaluated using sum-of-squares differences and distances between centers of segmented volumes of interest on shuttle and references images. Fiducial point analysis showed an average shuttling motion of 0.85 ± 1.05 mm (between-bed) and 1.18 ± 1.46 mm (between-phase), respectively. The volume-of-interest analysis of the nonrigid registration results showed improved sum-of-squares differences from 2950 to 597, between-bed distance from 1.64 to 1.20 mm, and between-phase distance from 2.64 to 1.33 mm, respectively, averaged over all cases. Shuttling effects introduced during shuttle-mode CT acquisitions can be computationally corrected for body perfusion applications.

Association between light absorption measurements of PM2.5 and distance from heavy traffic roads in the Mexico City metropolitan area.

PubMed

Cortez-Lugo, Marlene; Escamilla-Núñez, Consuelo; Barraza-Villarreal, Albino; Texcalac-Sangrador, José Luis; Chow, Judith; Watson, John; Hernández-Cadena, Leticia; Romieu, Isabelle

2013-04-01

To study the relationship between light absorption measurements of PM2.5 at various distances from heavy traffic roads and diesel vehicle counts in Mexico City. PM2.5 samples were obtained from June 2003-June 2005 in three MCMA regions. Light absorption (b abs) in a subset of PM2.5 samples was determined. We evaluated the effect of distance and diesel vehicle counts to heavy traffic roads on PM2.5 b abs using generalized estimating equation models. Median PM2.5 b abs measurements significantly decrease as distance from heavy traffic roads increases (p<0.002); levels decreased by 7% (CI95% 0.9-14) for each 100 additional meters from heavy traffic roads. Our model predicts that PM2.5 b abs measurements would increase by 20% (CI95% 3-38) as the hourly heavy diesel vehicle count increases by 150 per hour. PM2.5 b abs measurements are significantly associated with distance from motorways and traffic density and therefore can be used to assess human exposure to traffic-related emissions.

Matrix Completion Optimization for Localization in Wireless Sensor Networks for Intelligent IoT

PubMed Central

Nguyen, Thu L. N.; Shin, Yoan

2016-01-01

Localization in wireless sensor networks (WSNs) is one of the primary functions of the intelligent Internet of Things (IoT) that offers automatically discoverable services, while the localization accuracy is a key issue to evaluate the quality of those services. In this paper, we develop a framework to solve the Euclidean distance matrix completion problem, which is an important technical problem for distance-based localization in WSNs. The sensor network localization problem is described as a low-rank dimensional Euclidean distance completion problem with known nodes. The task is to find the sensor locations through recovery of missing entries of a squared distance matrix when the dimension of the data is small compared to the number of data points. We solve a relaxation optimization problem using a modification of Newton’s method, where the cost function depends on the squared distance matrix. The solution obtained in our scheme achieves a lower complexity and can perform better if we use it as an initial guess for an interactive local search of other higher precision localization scheme. Simulation results show the effectiveness of our approach. PMID:27213378

Evaluation of target acquisition difficulty using recognition distance to measure required retinal area

NASA Astrophysics Data System (ADS)

Nilsson, Thomy H.

2001-09-01

The psychophysical method of limits was used to measure the distance at which observers could distinguish military vehicles photographed in natural landscapes. Obtained from the TNO-TM Search_2 dataset, these pictures either were rear-projected 35-mm slides or were presented on a computer monitor. Based on the rationale that more difficult vehicle targets would require more visual pathways for recognition, difficult of acquisition was defined in terms of the relative retinal area required for recognition. Relative retinal area was derived from the inverse square of the recognition distance of a particular vehicle relative to the distance of the vehicle that could be seen furthest away. Results are compared with data on the time required to find the vehicles in these pictures. These comparison indicate recognition distance thresholds can be a suitable means of defining standards for the effectiveness of vital graphic information; and the two methods are complementary with respect to distinguishing different degrees of acquisition difficulty, and together may provide a means to measure the total information processing required for recognition.

Facilities Offered by the University of Ibadan (Nigeria) Distance Learning Centre towards Learners' Academic Goal--An Evaluation

ERIC Educational Resources Information Center

Adegbile, J. A.; Oyekanmi, J. O.

2011-01-01

Distance learners in the University of Ibadan, Nigeria unlike other distance learners of different parts of the world are faced with various educational, social and psychological problems associated with the code of distance learning. The facilities offered by the University of Ibadan distance learning centre towards the users' multifarious needs…

Egocentrism: Its Effect on the Form and Use of Grammar.

ERIC Educational Resources Information Center

Zubin, David A.

The concept of cognitive egocentrism is presented, supported with experimental evidence, and operationally defined on a scale of egocentric distance from "ego" ("speaker") to "hearer," to "other," to "concrete entity." This concept is used in evaluating the hypothesis that the nominative case in…

Maslow and Motherboards: Taking a Hierarchical View of Technology Planning.

ERIC Educational Resources Information Center

Johnson, Doug

2003-01-01

Presents a planning model for educational uses of technology that is based on Maslow's hierarchy of needs. Topics include established infrastructure; effective administration; extensive resources; enhanced teaching, including creating distance learning opportunities; empowered students, including evaluation methods and information literacy skills;…

Optimization of biostimulant for bioremediation of contaminated coastal sediment by response surface methodology (RSM) and evaluation of microbial diversity by pyrosequencing.

PubMed

Subha, Bakthavachallam; Song, Young Chae; Woo, Jung Hui

2015-09-15

The present study aims to optimize the slow release biostimulant ball (BSB) for bioremediation of contaminated coastal sediment using response surface methodology (RSM). Different bacterial communities were evaluated using a pyrosequencing-based approach in contaminated coastal sediments. The effects of BSB size (1-5cm), distance (1-10cm) and time (1-4months) on changes in chemical oxygen demand (COD) and volatile solid (VS) reduction were determined. Maximum reductions of COD and VS, 89.7% and 78.8%, respectively, were observed at a 3cm ball size, 5.5cm distance and 4months; these values are the optimum conditions for effective treatment of contaminated coastal sediment. Most of the variance in COD and VS (0.9291 and 0.9369, respectively) was explained in our chosen models. BSB is a promising method for COD and VS reduction and enhancement of SRB diversity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of clays on the fire-retardant properties of a polyethylenic copolymer containing intumescent formulation

PubMed Central

Ribeiro, Simone P S; Estevão, Luciana R M; Nascimento, Regina S V

2008-01-01

Organophilic clay particles were added to a standard intumescent formulation and, since the role of clay expansion or intercalation is still a matter of much controversy, several clays with varying degrees of interlayer distances were evaluated. The composites were obtained by blending the nanostructured clay and the intumescent system with a polyethylenic copolymer. The flame-retardant properties of the materials were evaluated by the limiting oxygen index (LOI), the UL-94 rating and thermogravimetric analysis (TGA). The results showed that the addition of highly expanded clays to the ammonium polyphosphate and pentaerythritol formulation does not significantly increase the flame retardancy of the mixture, when measured by the LOI and UL-94. However, when clays with smaller basal distances were added to the intumescent formulation, a synergistic effect was observed. In contrast, the simple addition of clays to the copolymer, without the intumescent formulation, did not increase the fire retardance of the materials. PMID:27877975

Effects of pipette modulation and imaging distances on ion currents measured with scanning ion conductance microscopy (SICM).

PubMed

Chen, Chiao-Chen; Baker, Lane A

2011-01-07

Local conductance variations can be estimated by measuring ion current magnitudes with scanning ion conductance microscopy (SICM). Factors which influence image quality and quantitation of ion currents measured with SICM have been evaluated. Specifically, effects of probe-sample separation and pipette modulation have been systematically studied for the case of imaging conductance variations at pores in a polymer membrane under transmembrane concentration gradients. The influence of probe-sample separation on ion current images was evaluated using distance-modulated (ac) feedback. Approach curves obtained using non-modulated (dc) feedback were also recorded to determine the relative influence of pipette-generated convection by comparison of ion currents measured with both ac and dc feedback modes. To better interpret results obtained, comparison to a model based on a disk-shaped geometry for nanopores in the membrane, as well as relevant position-dependent parameters of the experiment is described. These results advance our current understanding of conductance measurements with SICM.

Evaluating a Health Educational First aid Program with the Implementation of Synchronous Distance Learning.

PubMed

Ponirou, Paraskevi; Diomidous, Marianna; Mantas, John; Kalokairinou, Athena; Kalouri, Ourania; Kapadochos, Theodoros; Tzavara, Chara

2014-01-01

The education in First Aid through health education programs can help in promoting the health of the population. Meanwhile, the development of alternative forms of education with emphasis on distance learning implemented with e-learning creates an innovative system of knowledge and skills in different population groups. The main purpose of this research proposal is to investigate the effectiveness of the educational program to candidates educators about knowledge and emergency preparedness at school. The study used the Solomon four group design (2 intervention groups and 2 control groups). Statistical analysis showed significant difference within the four groups. Intervention groups had improved significantly their knowledge showing that the program was effective and that they would eventually deal with a threatening situation with right handlings. There were no statistical significant findings regarding other independent variables (p>0,05).The health education program with the implementation of synchronous distance learning succeeded to enhance the knowledge of candidates educators.

Person Re-Identification via Distance Metric Learning With Latent Variables.

PubMed

Sun, Chong; Wang, Dong; Lu, Huchuan

2017-01-01

In this paper, we propose an effective person re-identification method with latent variables, which represents a pedestrian as the mixture of a holistic model and a number of flexible models. Three types of latent variables are introduced to model uncertain factors in the re-identification problem, including vertical misalignments, horizontal misalignments and leg posture variations. The distance between two pedestrians can be determined by minimizing a given distance function with respect to latent variables, and then be used to conduct the re-identification task. In addition, we develop a latent metric learning method for learning the effective metric matrix, which can be solved via an iterative manner: once latent information is specified, the metric matrix can be obtained based on some typical metric learning methods; with the computed metric matrix, the latent variables can be determined by searching the state space exhaustively. Finally, extensive experiments are conducted on seven databases to evaluate the proposed method. The experimental results demonstrate that our method achieves better performance than other competing algorithms.

Construction and validation of a distance learning module on premedication antisepsis for nursing professionals.

PubMed

Pereira, Barbara Juliana da Costa; Mendes, Isabel Amélia Costa; Beatriz Maria, Jorge; Mazzo, Alessandra

2013-11-01

The aim of this descriptive study, carried out at a public university, was to design, develop, and validate a distance learning module on intramuscular premedication antisepsis. The content was introduced in the Modular Object-Oriented Dynamic Learning Environment, based on the Systematic Model for Web-Based Training projects. Ten nurses and information technologists at work consented to participate, in compliance with ethical guidelines, and answered a questionnaire to validate the Virtual Learning Environment. The educational aspects of the environment interface were mostly evaluated as "excellent," whereas the assessment of didactic resources indicated interactivity difficulties. It is concluded that distance learning is an important tool for the teaching of premedication antisepsis. To ensure its effectiveness, appropriate methods and interactive devices must be used.

New platform for evaluating ultrasound-guided interventional technologies

NASA Astrophysics Data System (ADS)

Kim, Younsu; Guo, Xiaoyu; Boctor, Emad M.

2016-04-01

Ultrasound-guided needle tracking systems are frequently used in surgical procedures. Various needle tracking technologies have been developed using ultrasound, electromagnetic sensors, and optical sensors. To evaluate these new needle tracking technologies, 3D volume information is often acquired to compute the actual distance from the needle tip to the target object. The image-guidance conditions for comparison are often inconsistent due to the ultrasound beam-thickness. Since 3D volumes are necessary, there is often some time delay between the surgical procedure and the evaluation. These evaluation methods will generally only measure the final needle location because they interrupt the surgical procedure. The main contribution of this work is a new platform for evaluating needle tracking systems in real-time, resolving the problems stated above. We developed new tools to evaluate the precise distance between the needle tip and the target object. A PZT element transmitting unit is designed as needle introducer shape so that it can be inserted in the needle. We have collected time of flight and amplitude information in real-time. We propose two systems to collect ultrasound signals. We demonstrate this platform on an ultrasound DAQ system and a cost-effective FPGA board. The results of a chicken breast experiment show the feasibility of tracking a time series of needle tip distances. We performed validation experiments with a plastisol phantom and have shown that the preliminary data fits a linear regression model with a RMSE of less than 0.6mm. Our platform can be applied to more general needle tracking methods using other forms of guidance.

[Mental health promotion in school with school coaches: evaluation of a pilot project].

PubMed

Corrieri, Sandro; Conrad, Ines; Riedel-Heller, Steffi G

2015-03-01

How did the work of four school coaches in five Saxonian schools influence children's and adolescents' psychosocial development? At three points in time, students at intervention (N = 292) and control schools (N = 300) were evaluated concerning their social distance towards mentally ill people and their help-seeking behavior in case of crisis. The survey also included teachers (N = 323) and parents (N = 370). Data analysis was done descriptively and with random effects models. The social distance of the intervention schools declined significantly compared to the control schools. Having heard or read about mental illnesses, or personally knowing somebody affected by mental illness, led to less social distance and more empathy. Information increased the confidence to receive help from a professional consultant. Friends and family were the main reference groups. The school coaches were accepted as confidential persons and helped with school and private issues. The school coaches' work showed positive influence on all members of the school system. © Georg Thieme Verlag KG Stuttgart · New York.

Usefulness of an Internet-based thematic learning network: comparison of effectiveness with traditional teaching.

PubMed

Coma Del Corral, María Jesús; Guevara, José Cordero; Luquin, Pedro Abáigar; Peña, Horacio J; Mateos Otero, Juan José

2006-03-01

UniNet is an Internet-based thematic network for a virtual community of users (VCU). It supports one multidisciplinary community of doctoral students, who receive most of the courses on the network. The evident advantages of distance learning by Internet, in terms of costs, comfort, etc., require a previous evaluation of the system, focusing on the learning outcomes of the student. The aim was to evaluate the real learning of the students of doctorate courses, by comparing the effectiveness of distance learning in UniNet with traditional classroom-based teaching. Five doctorate courses were taught simultaneously to two independent groups of students in two ways: one, through the UniNet Network, and the other in a traditional classroom. The academic knowledge of students was evaluated at the beginning and end of each course. The difference in score was considered as a knowledge increase. The comparison was made using Student's t-test for independent groups. There were no significant statistical differences in the outcomes of the two groups of students. This suggests that both teaching systems were equivalent in increasing the knowledge of the students. Both educational methods, the traditional system and the online system in a thematic network, are effective and similar for increasing knowledge.

Does silvoagropecuary landscape fragmentation affect the genetic diversity of the sigmodontine rodent Oligoryzomys longicaudatus?

PubMed Central

Lazo-Cancino, Daniela; Musleh, Selim S.; Hernandez, Cristian E.; Palma, Eduardo

2017-01-01

Background Fragmentation of native forests is a highly visible result of human land-use throughout the world. In this study, we evaluated the effects of landscape fragmentation and matrix features on the genetic diversity and structure of Oligoryzomys longicaudatus, the natural reservoir of Hantavirus in southern South America. We focused our work in the Valdivian Rainforest where human activities have produced strong change of natural habitats, with an important number of human cases of Hantavirus. Methods We sampled specimens of O. longicaudatus from five native forest patches surrounded by silvoagropecuary matrix from Panguipulli, Los Rios Region, Chile. Using the hypervariable domain I (mtDNA), we characterized the genetic diversity and evaluated the effect of fragmentation and landscape matrix on the genetic structure of O. longicaudatus. For the latter, we used three approaches: (i) Isolation by Distance (IBD) as null model, (ii) Least-cost Path (LCP) where genetic distances between patch pairs increase with cost-weighted distances, and (iii) Isolation by Resistance (IBR) where the resistance distance is the average number of steps that is needed to commute between the patches during a random walk. Results We found low values of nucleotide diversity (π) for the five patches surveyed, ranging from 0.012 to 0.015, revealing that the 73 sampled specimens of this study belong to two populations but with low values of genetic distance (γST) ranging from 0.022 to 0.099. Likewise, we found that there are no significant associations between genetic distance and geographic distance for IBD and IBR. However, we found for the LCP approach, a significant positive relationship (r = 0.737, p = 0.05), with shortest least-cost paths traced through native forest and arborescent shrublands. Discussion In this work we found that, at this reduced geographical scale, Oligoryzomys longicaudatus shows genetic signs of fragmentation. In addition, we found that connectivity between full growth native forest remnants is mediated by the presence of dense shrublands and native forest corridors. In this sense, our results are important because they show how native forest patches and associated routes act as source of vector species in silvoagropecuary landscape, increasing the infection risk on human population. This study is the first approach to understand the epidemiological spatial context of silvoagropecuary risk of Hantavirus emergence. Further studies are needed to elucidate the effects of landscape fragmentation in order to generate new predictive models based on vector intrinsic attributes and landscape features. PMID:28975057

Does silvoagropecuary landscape fragmentation affect the genetic diversity of the sigmodontine rodent Oligoryzomys longicaudatus?

PubMed

Lazo-Cancino, Daniela; Musleh, Selim S; Hernandez, Cristian E; Palma, Eduardo; Rodriguez-Serrano, Enrique

2017-01-01

Fragmentation of native forests is a highly visible result of human land-use throughout the world. In this study, we evaluated the effects of landscape fragmentation and matrix features on the genetic diversity and structure of Oligoryzomys longicaudatus, the natural reservoir of Hantavirus in southern South America. We focused our work in the Valdivian Rainforest where human activities have produced strong change of natural habitats, with an important number of human cases of Hantavirus. We sampled specimens of O. longicaudatus from five native forest patches surrounded by silvoagropecuary matrix from Panguipulli, Los Rios Region, Chile. Using the hypervariable domain I (mtDNA), we characterized the genetic diversity and evaluated the effect of fragmentation and landscape matrix on the genetic structure of O. longicaudatus . For the latter, we used three approaches: (i) Isolation by Distance (IBD) as null model, (ii) Least-cost Path (LCP) where genetic distances between patch pairs increase with cost-weighted distances, and (iii) Isolation by Resistance (IBR) where the resistance distance is the average number of steps that is needed to commute between the patches during a random walk. We found low values of nucleotide diversity ( π ) for the five patches surveyed, ranging from 0.012 to 0.015, revealing that the 73 sampled specimens of this study belong to two populations but with low values of genetic distance ( γ ST ) ranging from 0.022 to 0.099. Likewise, we found that there are no significant associations between genetic distance and geographic distance for IBD and IBR. However, we found for the LCP approach, a significant positive relationship ( r  = 0.737, p  = 0.05), with shortest least-cost paths traced through native forest and arborescent shrublands. In this work we found that, at this reduced geographical scale , Oligoryzomys longicaudatus shows genetic signs of fragmentation. In addition, we found that connectivity between full growth native forest remnants is mediated by the presence of dense shrublands and native forest corridors. In this sense, our results are important because they show how native forest patches and associated routes act as source of vector species in silvoagropecuary landscape, increasing the infection risk on human population. This study is the first approach to understand the epidemiological spatial context of silvoagropecuary risk of Hantavirus emergence. Further studies are needed to elucidate the effects of landscape fragmentation in order to generate new predictive models based on vector intrinsic attributes and landscape features.

Distance Education and Distance Learning: Some Psychological Considerations.

ERIC Educational Resources Information Center

Cropley, Arthur J.; Kahl, Thomas N.

1983-01-01

Compares and contrasts distance education and face-to-face education in terms of selected psychological dimensions, i.e., organization and learning, motivation, learning and communication processes, didactic activities and materials, and evaluation and feedback. Psychological aspects of distance education that may be favorable to learning are also…

Solving the aerodynamics of fungal flight: how air viscosity slows spore motion.

PubMed

Fischer, Mark W F; Stolze-Rybczynski, Jessica L; Davis, Diana J; Cui, Yunluan; Money, Nicholas P

2010-01-01

Viscous drag causes the rapid deceleration of fungal spores after high-speed launches and limits discharge distance. Stokes' law posits a linear relationship between drag force and velocity. It provides an excellent fit to experimental measurements of the terminal velocity of free-falling spores and other instances of low Reynolds number motion (Re<1). More complex, non-linear drag models have been devised for movements characterized by higher Re, but their effectiveness for modeling the launch of fast-moving fungal spores has not been tested. In this paper, we use data on spore discharge processes obtained from ultra-high-speed video recordings to evaluate the effects of air viscosity predicted by Stokes' law and a commonly used non-linear drag model. We find that discharge distances predicted from launch speeds by Stokes' model provide a much better match to measured distances than estimates from the more complex drag model. Stokes' model works better over a wide range projectile sizes, launch speeds, and discharge distances, from microscopic mushroom ballistospores discharged at <1 m s(-1) over a distance of <0.1mm (Re<1.0), to macroscopic sporangia of Pilobolus that are launched at >10 m s(-1) and travel as far as 2.5m (Re>100). Copyright © 2010 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Influence of extrinsic operational parameters on salt diffusion during ultrasound assisted meat curing.

PubMed

Inguglia, Elena S; Zhang, Zhihang; Burgess, Catherine; Kerry, Joseph P; Tiwari, Brijesh K

2018-02-01

The present study investigated the effect of geometric parameters of the ultrasound instrument during meat salting in order to enhance salt diffusion and salt distribution in pork meat on a lab scale. The effects of probe size (∅2.5 and 1.3cm) and of different distances between the transducer and the meat sample (0.3, 0.5, and 0.8cm) on NaCl diffusion were investigated. Changes in the moisture content and NaCl gain were used to evaluate salt distribution and diffusion in the samples, parallel and perpendicular to ultrasound propagation direction. Results showed that 0.3cm was the most efficient distance between the probe and the sample to ensure a higher salt diffusion rate. A distance of 0.5cm was however considered as a trade-off distance to ensure salt diffusion and maintenance of meat quality parameters. The enhancement of salt diffusion by ultrasound was observed to decrease with increased horizontal distance from the probe. This study is of valuable importance for meat processing industries willing to apply new technologies on a larger scale and with defined operational standards. The data suggest that the geometric parameters of ultrasound systems can have strong influence on the efficiency of ultrasonic enhancement of NaCl uptake in meat and can be a crucial element in determining salt uptake during meat processing. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of Long-Term Physical Activity Practice after Cardiac Rehabilitation on Some Risk Factors

ERIC Educational Resources Information Center

Freyssin, Celine, Jr.; Blanc, Philippe; Verkindt, Chantal; Maunier, Sebastien; Prieur, Fabrice

2011-01-01

The objective of this study was to evaluate the effects of long-term physical activity practice after a cardiac rehabilitation program on weight, physical capacity and arterial compliance. The Dijon Physical Activity Score was used to identify two groups: sedentary and active. Weight, distance at the 6-min walk test and the small artery elasticity…

Do Small Schools Improve Performance in Large, Urban Districts? Causal Evidence from New York City. Working Paper #01-12

ERIC Educational Resources Information Center

Schwartz, Amy Ellen; Stiefel, Leanna; Wiswall, Matthew

2012-01-01

We evaluate the effectiveness of small high school reform in the country's largest school district, New York City. Using a rich administrative dataset for multiple cohorts of students and distance between student residence and school to instrument for endogenous school selection, we find substantial heterogeneity in school effects: newly created…

Reducing Conflicts between Motor Vehicles and Pedestrians: The Separate and Combined Effects of Pavement Markings and a Sign Prompt

ERIC Educational Resources Information Center

Huybers, Sherry; Van Houten, Ron; Malenfant, J.E. Louis

2004-01-01

The effects of a symbolic "yield here to pedestrians" sign and advance yield pavement markings on pedestrian/motor vehicle conflicts, motorists' yielding behavior, and the distance motorists' yield in advance of crosswalks were evaluated at multilane crosswalks at uncontrolled T intersections. In Experiment 1, the sign, when used alone, reduced…

Designing, delivering and evaluating a distance learning nursing course responsive to students needs.

PubMed

Sowan, Azizeh K; Jenkins, Louise S

2013-06-01

The majority of available studies in distance learning in nursing and health lack the sufficient details of course design and delivery processes which greatly affect the learning outcomes. Also, little is available about the fairness of this method of education to students with limited access to course resources. We describe the design and delivery processes and experience, in terms of satisfaction and achievement, of undergraduate nursing students in a distance course. The difference in achievement between the distance students and a comparable cohort of hybrid students is also examined. We also demonstrate the possibility of providing accessible education to students with limited technological resources. Participants included all undergraduate nursing students who were enrolled in a distance and a hybrid section of a communication skills course offered at a School of Nursing in Jordan. The distance course was created using Blackboard and Tegrity learning management systems. The design and delivery processes of the distance course incorporated three pedagogical principles that enhance: (a) course access and navigation; (b) communication and interaction; and (c) active and collaborative learning experiences. After course completion, distance students completed a 27-item satisfaction questionnaire. Achievement in the course and correlates of satisfaction were measured. The final sample included 25 students in the distance section and 35 in the hybrid section (N=60). The mean score of overall satisfaction in the distance section was 4.14 (0.32) out of a 5-point scale, indicating a high satisfaction. Results revealed significant associations between total satisfaction score and achievement in the distance course, grade expected in the course, and frequency of accessing the course materials (p<.05). All distance students, including students with limited technological resources available at home, managed to successfully complete the course. Major concerns reported by distance students were related to lack of time management skills and negative attitudes toward group assignments. The mean final course grade of the distance section (80±8.2) was significantly higher than the hybrid section (72.2±9.5), (t=3.5, p<.05). The use of effective instructional strategies resulted in delivering successful distance learning, even for students with limited resources. Institutions have to make strategic decisions on how to optimize the use of technology to fit their individualized learning environments. Instructors need to become familiar with the characteristics of students cohort served by the course and design the course accordingly. In addition, students should be guided on how to manage their time in distance learning environments and work effectively in group assignments. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Validation of Foot Placement Locations from Ankle Data of a Kinect v2 Sensor

PubMed Central

Geerse, Daphne; Coolen, Bert; Kolijn, Detmar; Roerdink, Melvyn

2017-01-01

The Kinect v2 sensor may be a cheap and easy to use sensor to quantify gait in clinical settings, especially when applied in set-ups integrating multiple Kinect sensors to increase the measurement volume. Reliable estimates of foot placement locations are required to quantify spatial gait parameters. This study aimed to systematically evaluate the effects of distance from the sensor, side and step length on estimates of foot placement locations based on Kinect’s ankle body points. Subjects (n = 12) performed stepping trials at imposed foot placement locations distanced 2 m or 3 m from the Kinect sensor (distance), for left and right foot placement locations (side), and for five imposed step lengths. Body points’ time series of the lower extremities were recorded with a Kinect v2 sensor, placed frontoparallelly on the left side, and a gold-standard motion-registration system. Foot placement locations, step lengths, and stepping accuracies were compared between systems using repeated-measures ANOVAs, agreement statistics and two one-sided t-tests to test equivalence. For the right side at the 2 m distance from the sensor we found significant between-systems differences in foot placement locations and step lengths, and evidence for nonequivalence. This distance by side effect was likely caused by differences in body orientation relative to the Kinect sensor. It can be reduced by using Kinect’s higher-dimensional depth data to estimate foot placement locations directly from the foot’s point cloud and/or by using smaller inter-sensor distances in the case of a multi-Kinect v2 set-up to estimate foot placement locations at greater distances from the sensor. PMID:28994731

Validation of Foot Placement Locations from Ankle Data of a Kinect v2 Sensor.

PubMed

Geerse, Daphne; Coolen, Bert; Kolijn, Detmar; Roerdink, Melvyn

2017-10-10

The Kinect v2 sensor may be a cheap and easy to use sensor to quantify gait in clinical settings, especially when applied in set-ups integrating multiple Kinect sensors to increase the measurement volume. Reliable estimates of foot placement locations are required to quantify spatial gait parameters. This study aimed to systematically evaluate the effects of distance from the sensor, side and step length on estimates of foot placement locations based on Kinect's ankle body points. Subjects (n = 12) performed stepping trials at imposed foot placement locations distanced 2 m or 3 m from the Kinect sensor (distance), for left and right foot placement locations (side), and for five imposed step lengths. Body points' time series of the lower extremities were recorded with a Kinect v2 sensor, placed frontoparallelly on the left side, and a gold-standard motion-registration system. Foot placement locations, step lengths, and stepping accuracies were compared between systems using repeated-measures ANOVAs, agreement statistics and two one-sided t -tests to test equivalence. For the right side at the 2 m distance from the sensor we found significant between-systems differences in foot placement locations and step lengths, and evidence for nonequivalence. This distance by side effect was likely caused by differences in body orientation relative to the Kinect sensor. It can be reduced by using Kinect's higher-dimensional depth data to estimate foot placement locations directly from the foot's point cloud and/or by using smaller inter-sensor distances in the case of a multi-Kinect v2 set-up to estimate foot placement locations at greater distances from the sensor.

Recorded interactive seminars and follow-up discussions as an effective method for distance learning.

PubMed

Miller, Kenneth T; Hannum, Wallace M; Proffit, William R

2011-03-01

Previous studies have suggested that, although orthodontic residents prefer to be live and interactive in a seminar, they learn almost as much when watching a previously recorded interactive seminar and following up with live discussion. Our objective was to test the effectiveness and acceptability of using previously recorded interactive seminars and different types of live follow-up discussions. Residents at schools participating from a distance completed preseminar readings and at their convenience watched streaming video of some or all recordings of 4 interactive seminar sequences consisting of 6 seminars each. Afterward, distant residents participated in 1 of 4 types of interaction: local follow-up discussion, videoconference, teleconference, and no discussion. The effectiveness of the seminar sequences was tested by pretest and posttest scores. Acceptability was evaluated from ratings of aspects of the seminar and discussion experience. Open-ended questions allowed residents to express what they liked and to suggest changes in their experiences. In each seminar sequence, test scores of schools participating through recordings and follow-up discussions improved more than those participating live and interactive. After viewing, residents preferred local follow-up discussion, which was not statistically different from participating live and interactive both locally and from a distance. Videoconference and teleconference discussions were both more acceptable to residents than no follow-up discussion, which was found to be significantly below all methods tested. When residents are live and interactive in a seminar, there does not appear to be a significant difference between being local vs at a distance. Recorded interactive seminars with follow-up discussions are also an effective and acceptable method of distance learning. Residents preferred local follow-up discussion, but, at a distance, they preferred videoconference to both teleconference and no discussion. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Effectiveness of an ethics course delivered in traditional and non-traditional formats.

PubMed

Feldhaus, Charles R; Fox, Patricia L

2004-04-01

This paper details a three-credit-hour undergraduate ethics course that was delivered using traditional, distance, and compressed formats. OLS 263: Ethical Decisions in Leadership is a 200-level course offered by the Department of Organizational Leadership and Supervision in the Purdue School of Engineering and Technology at Indiana University Purdue University Indianapolis (IUPUI). Students in engineering, technology, business, nursing, and other majors take the course. In an effort to determine student perceptions of course and instructor effectiveness, end-of-course student survey data were compared using data from traditional, distance, and compressed sections of the course. In addition, learning outcomes from the final course project were evaluated using a standardized assessment rubric and scores on the course project.

Head restraint backset during routine automobile driving: drivers usually exceed the recommended guidelines.

PubMed

Shugg, Jarrod A J; Vernest, Kyle; Dickey, James P

2011-04-01

Although several previous studies have evaluated horizontal head restraint backset distances, few studies have evaluated them during driving. The purpose of this study was to measure this backset during routine automobile driving and to specifically evaluate the backset during individual driving tasks such as turning, stopping, starting, and lane changes. Fourteen subjects drove around a specified route through the city of Guelph, Ontario, Canada, that included residential, thruway, and highway driving; additional minor driving tasks, such as lane changes, were evaluated. The distance of head restraint to posterior aspect of the head was measured continuously throughout the drive using an ultrasonic measurement system. The timing of specific tasks was documented using a video camera. The average head-to-restraint distance throughout the driving route was 78.1 mm (standard deviation [SD] 24.8 mm); this distance did not vary significantly between the global measures during various driving areas (residential, thruway, and highway). We observed that the head restraint backsets during right turns (93.6 mm; SD 34.8 mm) were significantly larger compared to the other driving tasks (p < .001). The 7 males and 7 females showed similar backset distances: 84.52 mm (SD 12.08) and 71.68 mm (SD 5.53), respectively (p = .0785). We observed that most subjects maintain a relatively consistent head-to-restraint distance throughout their driving route; 2 subjects adopted very large head restraint backset distances throughout their drive and 2 others adopted very small head restraint backset distances-this appears to reflect driver posture. Twelve of 14 subjects had average backset distances that exceed the National Highway Traffic Safety Administration and the Federal Motor Vehicle Safety Standard guidelines, indicating that most drivers may be at risk for whiplash-like disorders if exposed to a rear impact while driving. Of the monitored driving tasks, turning, especially right turns, caused drivers to increase their head-to-restraint backset distance.

Evaluation and operationalization of a novel forest detrainment modeling approach for computational snow avalanche simulation

NASA Astrophysics Data System (ADS)

Teich, M.; Feistl, T.; Fischer, J.; Bartelt, P.; Bebi, P.; Christen, M.; Grêt-Regamey, A.

2013-12-01

Two-dimensional avalanche simulation software operating in three-dimensional terrain are widely used for hazard zoning and engineering to predict runout distances and impact pressures of snow avalanche events. Mountain forests are an effective biological protection measure; however, the protective capacity of forests to decelerate or even to stop avalanches that start within forested areas or directly above the treeline is seldom considered in this context. In particular, runout distances of small- to medium-scale avalanches are strongly influenced by the structural conditions of forests in the avalanche path. This varying decelerating effect has rarely been addressed or implemented in avalanche simulation. We present an evaluation and operationalization of a novel forest detrainment modeling approach implemented in the avalanche simulation software RAMMS. The new approach accounts for the effect of forests in the avalanche path by detraining mass, which leads to a deceleration and runout shortening of avalanches. The extracted avalanche mass caught behind trees stops immediately and, therefore, is instantly subtracted from the flow and the momentum of the stopped mass is removed from the total momentum of the avalanche flow. This relationship is parameterized by the empirical detrainment coefficient K [Pa] which accounts for the braking power of different forest types per unit area. To define K dependent on specific forest characteristics, we simulated 40 well-documented small- to medium-scale avalanches which released in and ran through forests with varying K-values. Comparing two-dimensional simulation results with one-dimensional field observations for a high number of avalanche events and simulations manually is however time consuming and rather subjective. In order to process simulation results in a comprehensive and standardized way, we used a recently developed automatic evaluation and comparison method defining runout distances based on a pressure-based runout indicator in an avalanche path dependent coordinate system. Analyzing and comparing observed and simulated runout distances statistically revealed values for K suitable to simulate the combined influence of four forest characteristics on avalanche runout: forest type, crown coverage, vertical structure and surface roughness, e.g. values for K were higher for dense spruce and mixed spruce-beech forests compared to open larch forests at the upper treeline. Considering forest structural conditions within avalanche simulation will improve current applications for avalanche simulation tools in mountain forest and natural hazard management considerably. Furthermore, we show that an objective and standardized evaluation of two-dimensional simulation results is essential for a successful evaluation and further calibration of avalanche models in general.

Designing a Workable Framework for Evaluating Distance Language Instruction

ERIC Educational Resources Information Center

Madyarov, Irshat

2009-01-01

Teaching foreign languages at distance is now becoming widespread; so is the need for evaluating online language courses. This article discusses an example of a framework that was applied to evaluate an online English as a foreign language (EFL) course at a Middle Eastern university. The development of the framework investigated areas of interest…

Training for Distance Teaching through Distance Learning.

ERIC Educational Resources Information Center

Cadorath, Jill; Harris, Simon; Encinas, Fatima

2002-01-01

Describes a mixed-mode bachelor degree course in English language teaching at the Universidad Autonoma de Puebla (Mexico) that was designed to help practicing teachers write appropriate distance education materials by giving them the experience of being distance students. Includes a course outline and results of a course evaluation. (Author/LRW)

Distance Education and Distributed Learning. Current Perspectives on Applied Information Technologies.

ERIC Educational Resources Information Center

Vrasidas, Charalambos, Ed.; Glass, Gene V., Ed.

This book describes the current state of developments in distance education and distributed learning. The volume brings together some of the leading contemporary contributors in the areas of educational technology and distance education. Topics covered include research and evaluation in distance education, online communities, faculty productivity,…

Developing Telecommunication Linkages for Microcomputer-Aided Instruction. TDC Research Report No. 1.

ERIC Educational Resources Information Center

Blinn, Charles R.; And Others

A project undertaken at the University of Minnesota evaluated two microcomputer teletraining systems (audiographic conferencing) to determine the effectiveness of this technology for point-to-point and multipoint distance education. System design requirements included broadcast keystrokes, error checking, master-slave linkages, simultaneous voice…

Developing metapopulation connectivity criteria from genetic and habitat data to recover the endangered Mexican wolf.

PubMed

Carroll, Carlos; Fredrickson, Richard J; Lacy, Robert C

2014-02-01

Restoring connectivity between fragmented populations is an important tool for alleviating genetic threats to endangered species. Yet recovery plans typically lack quantitative criteria for ensuring such population connectivity. We demonstrate how models that integrate habitat, genetic, and demographic data can be used to develop connectivity criteria for the endangered Mexican wolf (Canis lupus baileyi), which is currently being restored to the wild from a captive population descended from 7 founders. We used population viability analysis that incorporated pedigree data to evaluate the relation between connectivity and persistence for a restored Mexican wolf metapopulation of 3 populations of equal size. Decreasing dispersal rates greatly increased extinction risk for small populations (<150-200), especially as dispersal rates dropped below 0.5 genetically effective migrants per generation. We compared observed migration rates in the Northern Rocky Mountains (NRM) wolf metapopulation to 2 habitat-based effective distance metrics, least-cost and resistance distance. We then used effective distance between potential primary core populations in a restored Mexican wolf metapopulation to evaluate potential dispersal rates. Although potential connectivity was lower in the Mexican wolf versus the NRM wolf metapopulation, a connectivity rate of >0.5 genetically effective migrants per generation may be achievable via natural dispersal under current landscape conditions. When sufficient data are available, these methods allow planners to move beyond general aspirational connectivity goals or rules of thumb to develop objective and measurable connectivity criteria that more effectively support species recovery. The shift from simple connectivity rules of thumb to species-specific analyses parallels the previous shift from general minimum-viable-population thresholds to detailed viability modeling in endangered species recovery planning. © 2013 Society for Conservation Biology.

Nonlinear friction model for servo press simulation

NASA Astrophysics Data System (ADS)

Ma, Ninshu; Sugitomo, Nobuhiko; Kyuno, Takunori; Tamura, Shintaro; Naka, Tetsuo

2013-12-01

The friction coefficient was measured under an idealized condition for a pulse servo motion. The measured friction coefficient and its changing with both sliding distance and a pulse motion showed that the friction resistance can be reduced due to the re-lubrication during unloading process of the pulse servo motion. Based on the measured friction coefficient and its changes with sliding distance and re-lubrication of oil, a nonlinear friction model was developed. Using the newly developed the nonlinear friction model, a deep draw simulation was performed and the formability was evaluated. The results were compared with experimental ones and the effectiveness was verified.

Spatiotemporal Variation in Distance Dependent Animal Movement Contacts: One Size Doesn’t Fit All

PubMed Central

Brommesson, Peter; Wennergren, Uno; Lindström, Tom

2016-01-01

The structure of contacts that mediate transmission has a pronounced effect on the outbreak dynamics of infectious disease and simulation models are powerful tools to inform policy decisions. Most simulation models of livestock disease spread rely to some degree on predictions of animal movement between holdings. Typically, movements are more common between nearby farms than between those located far away from each other. Here, we assessed spatiotemporal variation in such distance dependence of animal movement contacts from an epidemiological perspective. We evaluated and compared nine statistical models, applied to Swedish movement data from 2008. The models differed in at what level (if at all), they accounted for regional and/or seasonal heterogeneities in the distance dependence of the contacts. Using a kernel approach to describe how probability of contacts between farms changes with distance, we developed a hierarchical Bayesian framework and estimated parameters by using Markov Chain Monte Carlo techniques. We evaluated models by three different approaches of model selection. First, we used Deviance Information Criterion to evaluate their performance relative to each other. Secondly, we estimated the log predictive posterior distribution, this was also used to evaluate their relative performance. Thirdly, we performed posterior predictive checks by simulating movements with each of the parameterized models and evaluated their ability to recapture relevant summary statistics. Independent of selection criteria, we found that accounting for regional heterogeneity improved model accuracy. We also found that accounting for seasonal heterogeneity was beneficial, in terms of model accuracy, according to two of three methods used for model selection. Our results have important implications for livestock disease spread models where movement is an important risk factor for between farm transmission. We argue that modelers should refrain from using methods to simulate animal movements that assume the same pattern across all regions and seasons without explicitly testing for spatiotemporal variation. PMID:27760155

Entangled-coherent-state quantum key distribution with entanglement witnessing

NASA Astrophysics Data System (ADS)

Simon, David S.; Jaeger, Gregg; Sergienko, Alexander V.

2014-01-01

An entanglement-witness approach to quantum coherent-state key distribution and a system for its practical implementation are described. In this approach, eavesdropping can be detected by a change in sign of either of two witness functions: an entanglement witness S or an eavesdropping witness W. The effects of loss and eavesdropping on system operation are evaluated as a function of distance. Although the eavesdropping witness W does not directly witness entanglement for the system, its behavior remains related to that of the true entanglement witness S. Furthermore, W is easier to implement experimentally than S. W crosses the axis at a finite distance, in a manner reminiscent of entanglement sudden death. The distance at which this occurs changes measurably when an eavesdropper is present. The distance dependence of the two witnesses due to amplitude reduction and due to increased variance resulting from both ordinary propagation losses and possible eavesdropping activity is provided. Finally, the information content and secure key rate of a continuous variable protocol using this witness approach are given.

A data-based conservation planning tool for Florida panthers

USGS Publications Warehouse

Murrow, Jennifer L.; Thatcher, Cindy A.; Van Manen, Frank T.; Clark, Joseph D.

2013-01-01

Habitat loss and fragmentation are the greatest threats to the endangered Florida panther (Puma concolor coryi). We developed a data-based habitat model and user-friendly interface so that land managers can objectively evaluate Florida panther habitat. We used a geographic information system (GIS) and the Mahalanobis distance statistic (D2) to develop a model based on broad-scale landscape characteristics associated with panther home ranges. Variables in our model were Euclidean distance to natural land cover, road density, distance to major roads, human density, amount of natural land cover, amount of semi-natural land cover, amount of permanent or semi-permanent flooded area–open water, and a cost–distance variable. We then developed a Florida Panther Habitat Estimator tool, which automates and replicates the GIS processes used to apply the statistical habitat model. The estimator can be used by persons with moderate GIS skills to quantify effects of land-use changes on panther habitat at local and landscape scales. Example applications of the tool are presented.

Determinants of 6-minute walk distance in patients with idiopathic pulmonary fibrosis undergoing lung transplant evaluation.

PubMed

Porteous, Mary K; Rivera-Lebron, Belinda N; Kreider, Maryl; Lee, James; Kawut, Steven M

2016-03-01

Little is known about the physiologic determinants of 6-minute walk distance in idiopathic pulmonary fibrosis. We investigated the demographic, pulmonary function, echocardiographic, and hemodynamic determinants of 6-minute walk distance in patients with idiopathic pulmonary fibrosis evaluated for lung transplantation. We performed a cross-sectional analysis of 130 patients with idiopathic pulmonary fibrosis who completed a lung transplantation evaluation at the Hospital of the University of Pennsylvania between 2005 and 2010. Multivariable linear regression analysis was used to generate an explanatory model for 6-minute walk distance. After adjustment for age, sex, race, height, and weight, the presence of right ventricular dilation was associated with a decrease of 50.9 m (95% confidence interval [CI], 8.4-93.3) in 6-minute walk distance ([Formula: see text]). For each 200-mL reduction in forced vital capacity, the walk distance decreased by 15.0 m (95% CI, 9.0-21.1; [Formula: see text]). For every increase of 1 Wood unit in pulmonary vascular resistance, the walk distance decreased by 17.3 m (95% CI, 5.1-29.5; [Formula: see text]). Six-minute walk distance in idiopathic pulmonary fibrosis depends in part on circulatory impairment and the degree of restrictive lung disease. Future trials that target right ventricular morphology, pulmonary vascular resistance, and forced vital capacity may potentially improve exercise capacity in patients with idiopathic pulmonary fibrosis.

A CT-based software tool for evaluating compensator quality in passively scattered proton therapy

NASA Astrophysics Data System (ADS)

Li, Heng; Zhang, Lifei; Dong, Lei; Sahoo, Narayan; Gillin, Michael T.; Zhu, X. Ronald

2010-11-01

We have developed a quantitative computed tomography (CT)-based quality assurance (QA) tool for evaluating the accuracy of manufactured compensators used in passively scattered proton therapy. The thickness of a manufactured compensator was measured from its CT images and compared with the planned thickness defined by the treatment planning system. The difference between the measured and planned thicknesses was calculated with use of the Euclidean distance transformation and the kd-tree search method. Compensator accuracy was evaluated by examining several parameters including mean distance, maximum distance, global thickness error and central axis shifts. Two rectangular phantoms were used to validate the performance of the QA tool. Nine patients and 20 compensators were included in this study. We found that mean distances, global thickness errors and central axis shifts were all within 1 mm for all compensators studied, with maximum distances ranging from 1.1 to 3.8 mm. Although all compensators passed manual verification at selected points, about 5% of the pixels still had maximum distances of >2 mm, most of which correlated with large depth gradients. The correlation between the mean depth gradient of the compensator and the percentage of pixels with mean distance <1 mm is -0.93 with p < 0.001, which suggests that the mean depth gradient is a good indicator of compensator complexity. These results demonstrate that the CT-based compensator QA tool can be used to quantitatively evaluate manufactured compensators.

Social distance influences the outcome evaluation of cooperation and conflict: Evidence from event-related potentials.

PubMed

Chen, Yezi; Lu, Jiamei; Wang, Yiwen; Feng, Zhouqi; Yuan, Bo

2017-04-24

Previous research shows that social distance plays an important role in promoting cooperation and that subtle cues that reduce social distance increase the tendency to cooperate. However, it is unclear how social distance influences our outcome evaluation of cooperative and conflict feedback. The present study investigated the influence of social distance on cooperative and conflict behavior and the evaluation process of the cooperative and conflict outcomes, using the event-related potentials (ERPs) technique. We recorded ERPs from 14 normal adults playing a social game task against a friend and a stranger. The results showed that the FRN (Feedback Related Negativity) and P300 were affected by the opponent's choice to cooperate or aggress; however, only the P300 was affected by social distance. Specifically, when the opponent chose to cooperate, the feedback elicited a smaller FRN and a larger P300 amplitude; and compared with playing against friends, the P300 had a larger amplitude when participants gaming with strangers. Our results indicate that at the early stage of the evaluation of cooperation and conflict outcomes, individuals may initially and quickly encode the valence of outcomes, judging whether an outcome is consistent with their expectations. However, at the late stage, which involves a top-down cognitive appraisal process, some social factors, such as social distance, may moderate processing of attention resource allocation of feedback about outcomes, and of higher-level motivation/affective appraisal. Copyright © 2017 Elsevier B.V. All rights reserved.

Padma 28 for intermittent claudication.

PubMed

Morling, Joanne R; Maxwell, Heather; Stewart, Marlene

2013-07-16

Intermittent claudication is pain caused by chronic occlusive arterial disease that develops in a limb during exercise and is relieved with rest. Most drug treatments of intermittent claudication have a limited effect in improving walking distance. Padma 28, a Tibetan herbal preparation, has been used to treat intermittent claudication, but there is debate as to whether Padma 28 produces a clinical benefit beyond the placebo effect. To determine whether Padma 28 is effective, compared with placebo or other medications, in increasing pain-free and maximum walking distance for patients with intermittent claudication. The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator (TSC) searched the Specialised Register (last searched April 2013), CENTRAL (2013, Issue 3) and clinical trials databases. In addition, a pharmaceutical company was contacted. Randomised controlled trials of Padma 28 compared with placebo or other pharmacological treatments in people suffering from intermittent claudication. All review authors independently assessed the selected studies and extracted the data. Risk of bias was evaluated independently by two review authors. Depending on the data provided in the individual trials, we extracted mean or median walking distance at the end of the trial, or change in walking distance over the course of the trial, or both. Where not provided, and whenever possible, the statistical significance of differences in these parameters between treatment and placebo groups in individual trials was calculated. Where possible, data were combined by meta-analysis. Five trials involving 365 participants were identified. All trials compared Padma 28 with placebo for at least 16 weeks of follow-up. Pain-free and maximum walking distances both increased significantly in the groups treated with Padma 28, with no significant change in the placebo group. In general, the studies presented results comparing the treatment arms before and after treatment but made no comparisons between the Padma 28 and placebo groups. Pooled data of maximum walking distance after treatment with Padma 28 and placebo from two studies indicated a statistically significant difference in maximum walking distance (mean difference (MD) 95.97 m, 95% confidence interval (CI) 79.07 m to 112.88 m, P < 0.00001). The clinical importance of these observed changes in walking distance is unclear as no quality of life data were reported. There was no effect on ankle brachial index. Mild side effects, especially gastrointestinal discomfort, tiredness and skin eruption, were reported but this outcome was not statistically significantly different between the groups (odds ratio (OR) 1.09, 95% CI 0.42 to 2.83, P = 0.86). Some evidence exists from individual trials to suggest that Padma 28 may be effective in increasing walking distances, at least in the short term (four months), in people with intermittent claudication. Side effects do not appear to be a problem. However, the longer term effects of treatment are unknown and the clinical significance of the improvements in walking distance are questionable. Moreover, the quality of the evidence is limited by the small sample size of the available trials, lack of detail on key elements required to assess sources of bias, such as around randomisation and blinding, limited reporting of statistical analyses that compared treatment groups, and relatively high withdrawal rates that were linked to the outcome that is patients were withdrawn if they failed to improve walking distance. There was also evidence of publication bias. We therefore feel there is currently insufficient evidence to support the use of Padma 28 in the routine management of intermittent claudication. Further well-designed research would be required to determine the true effects of this herbal preparation.

The role of the golden proportion in the evaluation of facial esthetics.

PubMed

Rossetti, Alberto; De Menezes, Marcio; Rosati, Riccardo; Ferrario, Virgilio F; Sforza, Chiarella

2013-09-01

To demonstrate if one or more golden relationships between different measurements of the human face exist. To make our measurements, we used three-dimensional (3D) stereophotogrammetry, which has proved to be the "gold standard" in the field of facial anthropometry. We obtained 3D stereophotogrammetric facial acquisitions of 400 healthy young adult subjects, then had them scored by an Evaluation Jury. Each subject received an esthetic evaluation ranging from 0 to 40. Individuals with a score larger than 28 were considered very attractive (VA), and individuals with a score lower than 12 were considered not attractive (NA). Fifteen subjects per group were chosen by chance, with a final total group of 60 subjects: 15 VA males, 15 NA males, 15 VA females, and 15 NA females. For each subject, a set of facial distances was obtained from the stereophotogrammetric facial reconstruction, and 10 ratios were computed. The effects of sex and attractiveness were tested by analysis of variance. Additionally, Student's t-tests verified if the ratios were statistically different from the golden ratio. For nine ratios, no significant effects of sex or attractiveness were found. Only the eye-mouth distance/height of the mandible ratio was significantly influenced by sex (P = .035) and attractiveness (P = .032). Seven out of 10 ratios were statistically different from the hypothetical value of 1.618, and only three of them were similar to the golden ratio. Ratios between 3D facial distances were not related to attractiveness. Most of the facial ratios were different from the golden ratio.

Scanning mass spectrometer for quantitative reaction studies on catalytically active microstructures.

PubMed

Roos, M; Kielbassa, S; Schirling, C; Häring, T; Bansmann, J; Behm, R J

2007-08-01

We describe an apparatus for spatially resolving scanning mass spectrometry which is able to measure the gas composition above catalytically active microstructures or arrays of these microstructures with a lateral resolution of better than 100 mum under reaction conditions and which allows us to quantitatively determine reaction rates on individual microstructures. Measurements of the three-dimensional gas composition at different vertical distances and separations between active structures allow the evaluation of gas phase mass transport effects. The system is based on a piezoelectrically driven positioning substage for controlled lateral and vertical positioning of the sample under a rigidly mounted capillary probe connecting to a mass spectrometer. Measurements can be performed at pressures in the range of <10(-2)-10 mbars and temperatures between room temperature and 450 degrees C. The performance of the setup is demonstrated using the CO oxidation reaction on Pt microstructures on Si with sizes between 100 and 300 mum and distances in the same order of magnitude, evaluating CO(2) formation and CO consumption above the microstructures. The rapidly decaying lateral resolution with increasing distance between sample and probe underlines the effects of (lateral) gas transport in the room between sample and probe. The reaction rates and apparent activation energy obtained from such measurements agree with previous data on extended surfaces, demonstrating the feasibility of determining absolute reaction rates on individual microstructures.

Safety performance testing of a modified Oregon multidirectional slip-base sign support : FOIL test numbers 98F002 and 98F004

DOT National Transportation Integrated Search

1997-07-01

This project evaluated the effectiveness of symbol traffic signs for young, middle-aged and elderly drivers. Daytime legibility distance and comprehension of 85 symbols in the Manual on Uniform Traffic Control Devices (MUTCD) were measured. Legibilit...

Technical Assistance to Early Interventionists in Rural Areas: An Empirical Evaluation.

ERIC Educational Resources Information Center

Cooper, Carolyn S.; McEvoy, Mary A.

This study assessed the effectiveness of a model for providing long distance technical assistance on teacher implementation of an intervention designed to increase child-child social interaction. Subjects were 10 preschool special education teachers and 40 preschool-aged children (some developing normally and some with mild to moderate…

ICTE Tallahassee 2001. International Conference on Technology and Education Proceedings (19th, Tallahassee, Florida, May 2-5, 2001).

ERIC Educational Resources Information Center

2001

The ICTE Tallahassee 2001 conference proceedings is organized into eight themes: "Harnessing the Internet To Raise Educational Standards"; "Policies and Strategies To Evaluate, Identify, and Acquire Effective Software"; "Technology Resources in Support of Learning"; "Distance, Flexible, and Open Learning";…

Re-evaluating causal modeling with mantel tests in landscape genetics

Treesearch

Samuel A. Cushman; Tzeidle N. Wasserman; Erin L. Landguth; Andrew J. Shirk

2013-01-01

The predominant analytical approach to associate landscape patterns with gene flow processes is based on the association of cost distances with genetic distances between individuals. Mantel and partial Mantel tests have been the dominant statistical tools used to correlate cost distances and genetic distances in landscape genetics. However, the inherent high...

Do isometric pull-down exercises increase the acromio-humeral distance?

PubMed

Sealey, P; Critchley, D

2017-06-01

To evaluate the effect of isometric shoulder extension in 90° shoulder flexion on the acromio-humeral distance, to establish the force required to achieve a clinically important increase in the acromio-humeral distance, and to investigate the practicality and reliability of real-time ultrasound measurement of the acromio-humeral distance in 90° shoulder forward flexion. Prospective single-group intervention. King's College London, Guy's Campus. Twenty healthy volunteers [five males and 15 females (40 shoulders)] with a mean age of 32 (standard deviation 10, range 19 to 55) years were recruited from the faculty and staff at King's College London. The acromio-humeral distance in asymptomatic participants was measured using real-time ultrasound in the neutral position at rest, at 90° shoulder flexion at rest, and while performing an isometric pull-down exercise at 100%, 50%, 30% and 10% maximal voluntary isometric contraction. Real-time ultrasound measures of the acromio-humeral distance. Of the 20 participants, 38 shoulders were imaged. In 90° shoulder flexion, pull-down exercises at all levels of force increased the acromio-humeral distance compared with no pull-down (P<0.05), but this was only clinically significant in males. Measures had excellent short-term intra-operator reliability. Isometric pull-down exercises lead to an increase in the acromio-humeral distance in asymptomatic males that may be clinically important, and therefore may be an appropriate exercise for patients with shoulder pathology. Ultrasound measurement of the acromio-humeral distance in 90° shoulder flexion is practical and reliable. Copyright © 2016 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Transport Equation Based Wall Distance Computations Aimed at Flows With Time-Dependent Geometry

NASA Technical Reports Server (NTRS)

Tucker, Paul G.; Rumsey, Christopher L.; Bartels, Robert E.; Biedron, Robert T.

2003-01-01

Eikonal, Hamilton-Jacobi and Poisson equations can be used for economical nearest wall distance computation and modification. Economical computations may be especially useful for aeroelastic and adaptive grid problems for which the grid deforms, and the nearest wall distance needs to be repeatedly computed. Modifications are directed at remedying turbulence model defects. For complex grid structures, implementation of the Eikonal and Hamilton-Jacobi approaches is not straightforward. This prohibits their use in industrial CFD solvers. However, both the Eikonal and Hamilton-Jacobi equations can be written in advection and advection-diffusion forms, respectively. These, like the Poisson s Laplacian, are commonly occurring industrial CFD solver elements. Use of the NASA CFL3D code to solve the Eikonal and Hamilton-Jacobi equations in advective-based forms is explored. The advection-based distance equations are found to have robust convergence. Geometries studied include single and two element airfoils, wing body and double delta configurations along with a complex electronics system. It is shown that for Eikonal accuracy, upwind metric differences are required. The Poisson approach is found effective and, since it does not require offset metric evaluations, easiest to implement. The sensitivity of flow solutions to wall distance assumptions is explored. Generally, results are not greatly affected by wall distance traits.

Transport Equation Based Wall Distance Computations Aimed at Flows With Time-Dependent Geometry

NASA Technical Reports Server (NTRS)

Tucker, Paul G.; Rumsey, Christopher L.; Bartels, Robert E.; Biedron, Robert T.

2003-01-01

Eikonal, Hamilton-Jacobi and Poisson equations can be used for economical nearest wall distance computation and modification. Economical computations may be especially useful for aeroelastic and adaptive grid problems for which the grid deforms, and the nearest wall distance needs to be repeatedly computed. Modifications are directed at remedying turbulence model defects. For complex grid structures, implementation of the Eikonal and Hamilton-Jacobi approaches is not straightforward. This prohibits their use in industrial CFD solvers. However, both the Eikonal and Hamilton-Jacobi equations can be written in advection and advection-diffusion forms, respectively. These, like the Poisson's Laplacian, are commonly occurring industrial CFD solver elements. Use of the NASA CFL3D code to solve the Eikonal and Hamilton-Jacobi equations in advective-based forms is explored. The advection-based distance equations are found to have robust convergence. Geometries studied include single and two element airfoils, wing body and double delta configurations along with a complex electronics system. It is shown that for Eikonal accuracy, upwind metric differences are required. The Poisson approach is found effective and, since it does not require offset metric evaluations, easiest to implement. The sensitivity of flow solutions to wall distance assumptions is explored. Generally, results are not greatly affected by wall distance traits.

Comparison of attraction capabilities associated with high-speed, dual-pneumatic vitrectomy probes.

PubMed

Dugel, Pravin U; Abulon, Dina J K; Dimalanta, Ramon

2015-05-01

To measure membrane attraction capabilities of enhanced 27-gauge, enhanced 25-gauge, and 23-gauge vitrectomy probes under various parameters. A membrane-on-cantilever apparatus was used to measure membrane attraction for enhanced 27-, enhanced 25-, and 23-gauge UltraVit probes (n = 6 for each). The following parameters were evaluated: effects of cut rates and duty cycles on membrane attraction distances, and flow rates and vacuum levels required to attract a membrane at a fixed distance. The enhanced 27-gauge probe had the shortest attraction distance across all cutting speeds and duty cycles. To attract a membrane at a fixed distance, increasing vacuum was necessary with higher cutting rates and smaller probe gauges but flow rate remained relatively constant. The biased open duty cycle was associated with a longer attraction distance than 50/50 or biased closed modes. The shorter membrane attraction distance of the enhanced 27-gauge probe versus 23-gauge and enhanced 25-gauge probes may permit greater membrane dissection precision while providing improved access to small tissue planes. Equivalent fluid flow capabilities of the 27-gauge probe compared with the 23-gauge and 25-gauge probes may provide efficient aspiration. Surgeon selection of duty cycle modes may improve intraoperative fluid control and expand the cutter utility as a multifunctional tool.

Establishing an efficient way to utilize the drought resistance germplasm population in wheat.

PubMed

Wang, Jiancheng; Guan, Yajing; Wang, Yang; Zhu, Liwei; Wang, Qitian; Hu, Qijuan; Hu, Jin

2013-01-01

Drought resistance breeding provides a hopeful way to improve yield and quality of wheat in arid and semiarid regions. Constructing core collection is an efficient way to evaluate and utilize drought-resistant germplasm resources in wheat. In the present research, 1,683 wheat varieties were divided into five germplasm groups (high resistant, HR; resistant, R; moderate resistant, MR; susceptible, S; and high susceptible, HS). The least distance stepwise sampling (LDSS) method was adopted to select core accessions. Six commonly used genetic distances (Euclidean distance, Euclid; Standardized Euclidean distance, Seuclid; Mahalanobis distance, Mahal; Manhattan distance, Manhat; Cosine distance, Cosine; and Correlation distance, Correlation) were used to assess genetic distances among accessions. Unweighted pair-group average (UPGMA) method was used to perform hierarchical cluster analysis. Coincidence rate of range (CR) and variable rate of coefficient of variation (VR) were adopted to evaluate the representativeness of the core collection. A method for selecting the ideal constructing strategy was suggested in the present research. A wheat core collection for the drought resistance breeding programs was constructed by the strategy selected in the present research. The principal component analysis showed that the genetic diversity was well preserved in that core collection.

The Influence of the Interlayer Distance on the Performance of Thermally Reduced Graphene Oxide Supercapacitors.

PubMed

Lin, Jun-Hong

2018-02-08

In this paper, cationic surfactant cetyltrimethylammonium bromide (CTAB) was employed to prevent the restack of the thermally reduce graphene oxide (TRG) sheets. A facile approach was demonstrated to effectively enlarge the interlayer distance of the TRG sheets through the ionic interaction between the intercalated CTAB and ionic liquids (ILs). The morphology of the composites and the interaction between the intercalated ionic species were systematically characterized by SEM, SAXS, XRD, TGA, and FTIR. In addition, the performance of the EDLC cells based on these TRG composites was evaluated. It was found that due to the increased interlayer distance (0.41 nm to 2.51 nm) that enlarges the accessible surface area for the IL electrolyte, the energy density of the cell can be significantly improved (23.1 Wh/kg to 62.5 Wh/kg).

Calibrating the orientation between a microlens array and a sensor based on projective geometry

NASA Astrophysics Data System (ADS)

Su, Lijuan; Yan, Qiangqiang; Cao, Jun; Yuan, Yan

2016-07-01

We demonstrate a method for calibrating a microlens array (MLA) with a sensor component by building a plenoptic camera with a conventional prime lens. This calibration method includes a geometric model, a setup to adjust the distance (L) between the prime lens and the MLA, a calibration procedure for determining the subimage centers, and an optimization algorithm. The geometric model introduces nine unknown parameters regarding the centers of the microlenses and their images, whereas the distance adjustment setup provides an initial guess for the distance L. The simulation results verify the effectiveness and accuracy of the proposed method. The experimental results demonstrate the calibration process can be performed with a commercial prime lens and the proposed method can be used to quantitatively evaluate whether a MLA and a sensor is assembled properly for plenoptic systems.

The Influence of the Interlayer Distance on the Performance of Thermally Reduced Graphene Oxide Supercapacitors

PubMed Central

Lin, Jun-Hong

2018-01-01

In this paper, cationic surfactant cetyltrimethylammonium bromide (CTAB) was employed to prevent the restack of the thermally reduce graphene oxide (TRG) sheets. A facile approach was demonstrated to effectively enlarge the interlayer distance of the TRG sheets through the ionic interaction between the intercalated CTAB and ionic liquids (ILs). The morphology of the composites and the interaction between the intercalated ionic species were systematically characterized by SEM, SAXS, XRD, TGA, and FTIR. In addition, the performance of the EDLC cells based on these TRG composites was evaluated. It was found that due to the increased interlayer distance (0.41 nm to 2.51 nm) that enlarges the accessible surface area for the IL electrolyte, the energy density of the cell can be significantly improved (23.1 Wh/kg to 62.5 Wh/kg). PMID:29419773

Reaching nearby sources: comparison between real and virtual sound and visual targets

PubMed Central

Parseihian, Gaëtan; Jouffrais, Christophe; Katz, Brian F. G.

2014-01-01

Sound localization studies over the past century have predominantly been concerned with directional accuracy for far-field sources. Few studies have examined the condition of near-field sources and distance perception. The current study concerns localization and pointing accuracy by examining source positions in the peripersonal space, specifically those associated with a typical tabletop surface. Accuracy is studied with respect to the reporting hand (dominant or secondary) for auditory sources. Results show no effect on the reporting hand with azimuthal errors increasing equally for the most extreme source positions. Distance errors show a consistent compression toward the center of the reporting area. A second evaluation is carried out comparing auditory and visual stimuli to examine any bias in reporting protocol or biomechanical difficulties. No common bias error was observed between auditory and visual stimuli indicating that reporting errors were not due to biomechanical limitations in the pointing task. A final evaluation compares real auditory sources and anechoic condition virtual sources created using binaural rendering. Results showed increased azimuthal errors, with virtual source positions being consistently overestimated to more lateral positions, while no significant distance perception was observed, indicating a deficiency in the binaural rendering condition relative to the real stimuli situation. Various potential reasons for this discrepancy are discussed with several proposals for improving distance perception in peripersonal virtual environments. PMID:25228855

Femtosecond-LASIK outcomes using the VisuMax®-MEL® 80 platform for mixed astigmatism refractive surgery.

PubMed

Stanca, Horia Tudor; Munteanu, Mihnea; Jianu, Dragoş Cătălin; Motoc, Andrei Gheorghe Marius; Jecan, Cristian Radu; Tăbăcaru, Bogdana; Stanca, Simona; Preda, Maria Alexandra

2018-01-01

To evaluate the predictability, efficacy and safety of Femtosecond-laser-assisted in situ keratomileusis (LASIK) procedure for mixed astigmatism. We prospectively evaluated for 12 months 74 eyes (52 patients) with mixed astigmatism that underwent Femtosecond-LASIK treatment. The preoperative mean refractive sphere value was +1.879±1.313 diopters (D) and the mean refractive cylinder value was -4.169±1.091 D. The anterior corneal flap was cut using the VisuMax® femtosecond laser and then the stromal ablation was done using the MEL® 80 excimer laser. Mean age was 30.22±6.421 years with 61.53% female patients. Postoperative spherical equivalent at 12 months was within ±0.5D of emmetropia in 75.8% of eyes and within ±1D in 97.3% of eyes. Postoperative uncorrected distance visual acuity was equivalent to or better than the preoperative corrected distance visual acuity in 91.9% of eyes. Compared to the preoperative corrected distance visual acuity (CDVA), 8.1% of eyes gained one line, 2.7% gained two lines and 2.7% gained three lines of visual acuity. Femtosecond-LASIK using the VisuMax®-MEL® 80 platform appears to have safe, effective and predictable results in mixed astigmatic eyes. The results are impressive for high refractive error treatment and for improvement of both uncorrected and corrected distance visual acuity.

The role of semantic self-perceptions in temporal distance perceptions toward autobiographical events: the semantic congruence model.

PubMed

Gebauer, Jochen E; Haddock, Geoffrey; Broemer, Philip; von Hecker, Ulrich

2013-11-01

Why do some autobiographical events feel as if they happened yesterday, whereas others feel like ancient history? Such temporal distance perceptions have surprisingly little to do with actual calendar time distance. Instead, psychologists have found that people typically perceive positive autobiographical events as overly recent, while perceiving negative events as overly distant. The origins of this temporal distance bias have been sought in self-enhancement strivings and mood congruence between autobiographical events and chronic mood. As such, past research exclusively focused on the evaluative features of autobiographical events, while neglecting semantic features. To close this gap, we introduce a semantic congruence model. Capitalizing on the Big Two self-perception dimensions, Study 1 showed that high semantic congruence between recalled autobiographical events and trait self-perceptions render the recalled events subjectively recent. Specifically, interpersonally warm (competent) individuals perceived autobiographical events reflecting warmth (competence) as relatively recent, but warm (competent) individuals did not perceive events reflecting competence (warmth) as relatively recent. Study 2 found that conscious perceptions of congruence mediate these effects. Studies 3 and 4 showed that neither mood congruence nor self-enhancement account for these results. Study 5 extended the results from the Big Two to the Big Five self-perception dimensions, while affirming the independence of the semantic congruence model from evaluative influences. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Evaluation of pollen dispersal and cross pollination using transgenic grapevine plants.

PubMed

Harst, Margit; Cobanov, Beatrix-Axinja; Hausmann, Ludger; Eibach, Rudolf; Töpfer, Reinhard

2009-01-01

Public debate about the possible risk of genetically modified plants often concerns putative effects of pollen dispersal and out-crossing into conventional fields in the neighborhood of transgenic plants. Though Vitis vinifera (grapevine) is generally considered to be self-pollinating, it cannot be excluded that vertical gene transfer might occur. For monitoring pollen flow and out-crossing events, transgenic plants of Vitis vinifera cv. 'Dornfelder' harboring the gus-int gene were planted in the center of a field experiment in Southwest Germany in 1999. The rate of pollen dispersal was determined by pollen traps placed at radial distances of 5-150 m from the pollen-donor plants, at 1.00 and 1.80 m above ground. Transgenic pollen was evaluated by GUS staining, and could clearly be distinguished from pollen originating from non-transgenic grapevine plants. Transgenic pollen was observed up to 150 m from the pollen donors. The rate of out-crossing was determined by sampling seeds of selected grapevines at a distance of 10 m to the pollen source, and of a sector at 20 m distance, respectively, followed by GUS analysis of seedlings. The average cross-pollination rate during the experiment (2002-2004) was 2.7% at a distance of 20 m. The results of this first pilot study present a good base for further assessment under the conditions of normal viticulture practice.

CYBER WARFARE GOVERNANCE: EVALUATION OF CURRENT INTERNATIONAL AGREEMENTS ON THE OFFENSIVE USE OF CYBER

DTIC Science & Technology

2015-10-01

AIR COMMAND AND STAFF COLLEGE DISTANCE LEARNING AIR UNIVERSITY CYBER WARFARE GOVERNANCE: EVALUATION OF CURRENT INTERNATIONAL AGREEMENTS ON THE...order to prevent catastrophic second and third order effects. Rule 43 “prohibits means or methods of cyber warfare that indiscriminate by nature...Means and methods of cyber warfare are indiscriminate by nature if they cannot be: directed at a specific military objective, or limited in their

Change in skeletal muscle stiffness after running competition is dependent on both running distance and recovery time: a pilot study.

PubMed

Sadeghi, Seyedali; Newman, Cassidy; Cortes, Daniel H

2018-01-01

Long-distance running competitions impose a large amount of mechanical loading and strain leading to muscle edema and delayed onset muscle soreness (DOMS). Damage to various muscle fibers, metabolic impairments and fatigue have been linked to explain how DOMS impairs muscle function. Disruptions of muscle fiber during DOMS exacerbated by exercise have been shown to change muscle mechanical properties. The objective of this study is to quantify changes in mechanical properties of different muscles in the thigh and lower leg as function of running distance and time after competition. A custom implementation of Focused Comb-Push Ultrasound Shear Elastography (F-CUSE) method was used to evaluate shear modulus in runners before and after a race. Twenty-two healthy individuals (age: 23 ± 5 years) were recruited using convenience sampling and split into three race categories: short distance (nine subjects, 3-5 miles), middle distance (10 subjects, 10-13 miles), and long distance (three subjects, 26+ miles). Shear Wave Elastography (SWE) measurements were taken on both legs of each subject on the rectus femoris (RF), vastus lateralis (VL), vastus medialis (VM), soleus, lateral gastrocnemius (LG), medial gastrocnemius (MG), biceps femoris (BF) and semitendinosus (ST) muscles. For statistical analyses, a linear mixed model was used, with recovery time and running distance as fixed variables, while shear modulus was used as the dependent variable. Recovery time had a significant effect on the soleus ( p  = 0.05), while running distance had considerable effect on the biceps femoris ( p  = 0.02), vastus lateralis ( p  < 0.01) and semitendinosus muscles ( p  = 0.02). Sixty-seven percent of muscles exhibited a decreasing stiffness trend from before competition to immediately after competition. The preliminary results suggest that SWE could potentially be used to quantify changes of muscle mechanical properties as a way for measuring recovery procedures for runners.

Use of Disease-modifying Antirheumatic Drugs for Inflammatory Arthritis in US Veterans: Effect of Specialty Care and Geographic Distance.

PubMed

Walsh, Jessica A; Pei, Shaobo; Burningham, Zachary; Penmetsa, Gopi; Cannon, Grant W; Clegg, Daniel O; Sauer, Brian C

2018-03-01

To evaluate the effect of access to and distance from rheumatology care on the use of disease-modifying antirheumatic drugs (DMARD) in US veterans with inflammatory arthritis (IA). Provider encounters and DMARD dispensations for IA (rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis) were evaluated in national Veterans Affairs (VA) datasets between January 1, 2015, and December 31, 2015. Among 12,589 veterans with IA, 23.5% saw a rheumatology provider. In the general IA population, 25.3% and 13.6% of veterans were exposed to a synthetic DMARD (sDMARD) and biologic DMARD (bDMARD), respectively. DMARD exposure was 2.6- to 3.4-fold higher in the subpopulation using rheumatology providers, compared to the general IA population. The distance between veterans' homes and the closest VA rheumatology site was < 40 miles (Near) for 55.9%, 40-99 miles (Intermediate) for 31.7%, and ≥ 100 miles (Far) for 12.4%. Veterans in the Intermediate and Far groups were less likely to see a rheumatology provider than veterans in the Near group (RR = 0.72 and RR = 0.49, respectively). Exposure to bDMARD was 34% less frequent in the Far group than the Near group. In the subpopulation who used rheumatology care, the bDMARD exposure discrepancy did not persist between distance groups. Use of rheumatology care and DMARD was low for veterans with IA. DMARD exposure was strongly associated with rheumatology care use. Veterans in the general IA population living far from rheumatology sites accessed rheumatology care and bDMARD less frequently than veterans living close to rheumatology sites.

The numerical distance effect is task dependent.

PubMed

Goldfarb, Liat; Henik, Avishai; Rubinsten, Orly; Bloch-David, Yafit; Gertner, Limor

2011-11-01

Number comparison tasks produce a distance effect e.g., Moyer & Landauer (Nature 215: 1519-1520, 1967). It has been suggested that this effect supports the existence of semantic mental representations of numbers. In a matching task, a distance effect also appears, which suggests that the effect has an automatic semantic component. Recently, Cohen (Psychonomic Bulletin & Review 16: 332-336, 2009) suggested that in both automatic and intentional tasks, the distance effect might reflect not a semantic number representation, but a physical similarity between digits. The present article (1) compares the distance effect in the automatic matching task with that in the intentional number comparison task and suggests that, in the latter, the distance effect does include an additional semantic component; and (2) indicates that the distance effect in the standard automatic matching task is questionable and that its appearance in previous matching tasks was based on the specific analysis and design that were applied.

Antigenic Distance Measurements for Seasonal Influenza Vaccine Selection

PubMed Central

Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

2011-01-01

Influenza vaccination is one of the major options to counteract the effects of influenza diseases. Selection of an effective vaccine strain is the key to the success of an effective vaccination program since vaccine protection can only be achieved when the selected influenza vaccine strain matches the antigenic variants causing future outbreaks. Identification of an antigenic variant is the first step to determine whether vaccine strain needs to be updated. Antigenic distance derived from immunological assays, such as hemagglutination inhibition, is commonly used to measure the antigenic closeness between circulating strains and the current influenza vaccine strain. Thus, consensus on an explicit and robust antigenic distance measurement is critical in influenza surveillance. Based on the current seasonal influenza surveillance procedure, we propose and compare three antigenic distance measurements, including Average antigenic distance (A-distance), Mutual antigenic distance (M-distance), and Largest antigenic distance (L-distance). With the assistance of influenza antigenic cartography, our simulation results demonstrated that M-distance is a robust influenza antigenic distance measurement. Experimental results on both simulation and seasonal influenza surveillance data demonstrate that M-distance can be effectively utilized in influenza vaccine strain selection. PMID:22063385

Diffusion-enhanced Förster resonance energy transfer and the effects of external quenchers and the donor quantum yield.

PubMed

Jacob, Maik H; Dsouza, Roy N; Ghosh, Indrajit; Norouzy, Amir; Schwarzlose, Thomas; Nau, Werner M

2013-01-10

The structural and dynamic properties of a flexible peptidic chain codetermine its biological activity. These properties are imprinted in intrachain site-to-site distances as well as in diffusion coefficients of mutual site-to-site motion. Both distance distribution and diffusion determine the extent of Förster resonance energy transfer (FRET) between two chain sites labeled with a FRET donor and acceptor. Both could be obtained from time-resolved FRET measurements if their individual contributions to the FRET efficiency could be systematically varied. Because the FRET diffusion enhancement (FDE) depends on the donor-fluorescence lifetime, it has been proposed that the FDE can be reduced by shortening the donor lifetime through an external quencher. Benefiting from the high diffusion sensitivity of short-distance FRET, we tested this concept experimentally on a (Gly-Ser)(6) segment labeled with the donor/acceptor pair naphthylalanine/2,3-diazabicyclo[2.2.2]oct-2-ene (NAla/Dbo). Surprisingly, the very effective quencher potassium iodide (KI) had no effect at all on the average donor-acceptor distance, although the donor lifetime was shortened from ca. 36 ns in the absence of KI to ca. 3 ns in the presence of 30 mM KI. We show that the proposed approach had to fail because it is not the experimentally observed but the radiative donor lifetime that controls the FDE. Because of that, any FRET ensemble measurement can easily underestimate diffusion and might be misleading even if it employs the Haas-Steinberg diffusion equation (HSE). An extension of traditional FRET analysis allowed us to evaluate HSE simulations and to corroborate as well as generalize the experimental results. We demonstrate that diffusion-enhanced FRET depends on the radiative donor lifetime as it depends on the diffusion coefficient, a useful symmetry that can directly be applied to distinguish dynamic and structural effects of viscous cosolvents on the polymer chain. We demonstrate that the effective FRET rate and the recovered donor-acceptor distance depend on the quantum yield, most strongly in the absence of diffusion, which has to be accounted for in the interpretation of distance trends monitored by FRET.

Effect of Geographic Distance on Distance Education: An Empirical Study

ERIC Educational Resources Information Center

Luo, Heng; Robinson, Anthony C.; Detwiler, Jim

2014-01-01

This study investigates the effect of geographic distance on students' distance learning experience with the aim to provide tentative answers to a fundamental question--does geographic distance matter in distance education? Using educational outcome data collected from an online master's program in Geographic Information Systems, this study…

Road traffic and nearby grassland bird patterns in a suburbanizing landscape.

PubMed

Forman, Richard T T; Reineking, Bjorn; Hersperger, Anna M

2002-06-01

An extensive road system with rapidly increasing traffic produces diverse ecological effects that cover a large land area. Our objective was to evaluate the effect of roads with different traffic volumes on surrounding avian distributions, and its importance relative to other variables. Grassland bird data (5 years) for 84 open patches in an outer suburban/rural landscape near Boston were analyzed relative to: distance from roads with 3000-8000 to >30,000 vehicles/day; open-habitat patch size; area of quality microhabitat within a patch; adjacent land use; and distance to other open patches. Grassland bird presence and regular breeding correlated significantly with both distance from road and habitat patch size. Distance to nearest other open patch, irrespective of size, was not significant. Similarly, except for one species, adjacent land use, in this case built area, was not significant. A light traffic volume of 3000-8000 vehicles/day (local collector street here) had no significant effect on grassland bird distribution. For moderate traffic of 8000-15,000 (through street), there was no effect on bird presence although regular breeding was reduced for 400 m from a road. For heavier traffic of 15,000-30,000 (two-lane highway), both bird presence and breeding were decreased for 700 m. For a heavy traffic volume of > or =30,000 vehicles/day (multilane highway), bird presence and breeding were reduced for 1200 m from a road. The results suggest that avian studies and long-term surveys near busy roads may be strongly affected by traffic volume or changes in volume. We conclude that road ecology, especially the effects extending outward >100 m from roads with traffic, is a sine qua non for effective land-use and transportation policy.

Evaluation of jamming efficiency for the protection of a single ground object

NASA Astrophysics Data System (ADS)

Matuszewski, Jan

2018-04-01

The electronic countermeasures (ECM) include methods to completely prevent or restrict the effective use of the electromagnetic spectrum by the opponent. The most widespread means of disorganizing the operation of electronic devices is to create active and passive radio-electronic jamming. The paper presents the way of jamming efficiency calculations for protecting ground objects against the radars mounted on the airborne platforms. The basic mathematical formulas for calculating the efficiency of active radar jamming are presented. The numerical calculations for ground object protection are made for two different electronic warfare scenarios: the jammer is placed very closely and in a determined distance from the protecting object. The results of these calculations are presented in the appropriate figures showing the minimal distance of effective jamming. The realization of effective radar jamming in electronic warfare systems depends mainly on the precise knowledge of radar and the jammer's technical parameters, the distance between them, the assumed value of the degradation coefficient, the conditions of electromagnetic energy propagation and the applied jamming method. The conclusions from these calculations facilitate making a decision regarding how jamming should be conducted to achieve high efficiency during the electronic warfare training.

Accreditation of Distance Learning in the Field of Dentistry

ERIC Educational Resources Information Center

Hanlon, Linda L.

2004-01-01

This study looked at criteria important to dental accreditation consultants when evaluating programs that utilized some distance technology. Attitudinal and demographic data were collected to determine any relationships between these profiles and how a consultant would apply predetermined evaluative criteria. Descriptive statistics, internal…

Dynamic Evaluation of Distance Education Courses.

ERIC Educational Resources Information Center

Champagne, Matthew V.

This paper focuses on the Interactive and Distance Education Assessment (IDEA) laboratory, an assessment system developed by psychology students and faculty at Rensselaer Polytechnic Institute (New York) that incorporated learning styles, teaching styles, and other measures of individual difference into the evaluation of interactive and distance…

Evaluation of a multimodal, distance learning HIV management course for clinical care providers in India.

PubMed

Chang, Larry William; Kadam, Dileep B; Sangle, Shashi; Narayanan, Shivakumar; Borse, Rohidas T; McKenzie-White, Jane; Bowen, Craig W; Sisson, Stephen D; Bollinger, Robert C

2012-01-01

Distance learning is an important tool for training HIV health workers. However, there is limited evidence on design and evaluation of distance learning HIV curricula and tools. We therefore designed, implemented, and evaluated a distance learning course on HIV management for clinical care providers in India. After course completion, participant scores rose significantly from a pretest (78.4% mean correct) compared with the posttest (87.5%, P < .001). After course completion, participants were more likely to be confident in starting an initial antiretroviral (ARV) regimen, understanding ARV toxicities, encouraging patient adherence, diagnosing immune reconstitution syndrome, and monitoring patients on ARV medications (P ≤ .05). All participants (100%) strongly agreed/agreed that they would recommend this course to others, and most of them (96%) strongly agreed/agreed that they would take a course in this format again. A pragmatic approach to HIV curriculum development and evaluation resulted in reliable learning outcomes, as well as learner satisfaction and improvement in knowledge.

Sensors for 3D Imaging: Metric Evaluation and Calibration of a CCD/CMOS Time-of-Flight Camera.

PubMed

Chiabrando, Filiberto; Chiabrando, Roberto; Piatti, Dario; Rinaudo, Fulvio

2009-01-01

3D imaging with Time-of-Flight (ToF) cameras is a promising recent technique which allows 3D point clouds to be acquired at video frame rates. However, the distance measurements of these devices are often affected by some systematic errors which decrease the quality of the acquired data. In order to evaluate these errors, some experimental tests on a CCD/CMOS ToF camera sensor, the SwissRanger (SR)-4000 camera, were performed and reported in this paper. In particular, two main aspects are treated: the calibration of the distance measurements of the SR-4000 camera, which deals with evaluation of the camera warm up time period, the distance measurement error evaluation and a study of the influence on distance measurements of the camera orientation with respect to the observed object; the second aspect concerns the photogrammetric calibration of the amplitude images delivered by the camera using a purpose-built multi-resolution field made of high contrast targets.

Evaluation of the Competitive Environment for White Pine (Pinus strobus L.) Seedlings Planted on Prescribed Burn Sites in the Southern Appalachians

Treesearch

Katherine J. Elliott; James M. Vose

1995-01-01

We evaluated the competitive environment around planted white pine (Pinus strobus L.) seedlings and monitored the response of seedling growth to competition from naturally regenerating herbaceous and woody species for 2 yr after prescribed burning. We evaluated the bility of distance-independent and distance-dependent competition indices to predict resource...

Assuring Quality Evaluation Practices in Open and Distance Learning System: The Case of National Open University of Nigeria

ERIC Educational Resources Information Center

Ofoha, D.

2012-01-01

The success of any open and distance learning (ODL) programme depends on how well it is evaluated. In the National Open University of Nigeria (NOUN), students are assessed and evaluated through continuous assessment as well as end of semester examinations. This paper focuses on Tutor Marked Assignment (TMA), which forms part of continuous…

Emotions predictably modify response times in the initiation of human motor actions: A meta-analytic review.

PubMed

Beatty, Garrett F; Cranley, Nicole M; Carnaby, Giselle; Janelle, Christopher M

2016-03-01

Emotions motivate individuals to attain appetitive goals and avoid aversive consequences. Empirical investigations have detailed how broad approach and avoidance orientations are reflected in fundamental movement attributes such as the speed, accuracy, and variability of motor actions. Several theoretical perspectives propose explanations for how emotional states influence the speed with which goal directed movements are initiated. These perspectives include biological predisposition, muscle activation, distance regulation, cognitive evaluation, and evaluative response coding accounts. A comprehensive review of literature and meta-analysis were undertaken to quantify empirical support for these theoretical perspectives. The systematic review yielded 34 studies that contained 53 independent experiments producing 128 effect sizes used to evaluate the predictions of existing theories. The central tenets of the biological predisposition (Hedges' g = -0.356), distance regulation (g = -0.293; g = 0.243), and cognitive evaluation (g = -0.249; g = -0.405; g = -0.174) accounts were supported. Partial support was also identified for the evaluative response coding (g = -0.255) framework. Our findings provide quantitative evidence that substantiate existing theoretical perspectives, and provide potential direction for conceptual integration of these independent perspectives. Recommendations for future empirical work in this area are discussed. (c) 2016 APA, all rights reserved).

Effectiveness of breast fixation to reduce migration of the tip of a totally implantable venous access port in women.

PubMed

Song, Myung Gyu; Seo, Tae-Seok; Kim, Yun Hwan; Cho, Sung Bum; Jung, Euichul; Chung, Hwan Hoon; Lee, Seung Hwa

2016-07-12

To evaluate effectiveness of breast fixation to reduce migration of the catheter tip of a totally implantable venous access port (TIVP) in women. TIVPs were placed in 129 women via the right axillary vein from July 2012 to December 2014, with a final study population of 118 patients (mean age, 55.3 ± 13.8 years; range, 21-91 years). The patients were divided into two groups according to breast fixation during TIVP placement. A total of 56 patients received TIVP placement without breast fixation (Group 1); the remaining 62 received TIVP placement in the supine position after fixation of the ipsilateral breast on the abdominal wall in the sitting position (Group 2). Medical records were retrospectively reviewed for age, weight, height, body mass index, and underlying malignancy. We evaluated the difference in distance ratios between the port chamber and the catheter tip on supine chest and erect chest radiographs, respectively. Statistical analysis was performed using Student's t test. Differences in all parameters between Group 1 and Group 2 were not statistically significant. Mean distance ratio between the port chamber and the catheter tip was 1.95 ± 0.97 in Group 1 and 1.33 ± 0.59 in Group 2. Differences in distance ratios between the port chamber and the catheter tip were statistically significant between Group 1 and Group 2 (p = 0.001). Breast fixation seems to be effective in reducing migration of the port chamber and catheter tip with position changes in female patients during TIVP placement.

Quantifying the effects of research band resighting activities on staging terns in comparison to other disturbances

USGS Publications Warehouse

Althouse, Melissa; Cohen, Jonathan B.; Spendelow, Jeffrey A.; Karpanty, Sarah M.; Davis, Kayla L.; Parsons, Katharine C.; Luttazi, Cristin F.

2016-01-01

Avian research that involves potential disturbance to the study species may have unintended fitness consequences and could lead to biases in measurements of interest. The effects of band resighting on the behavior of mixed-species flocks of staging waterbirds were evaluated against recreational pedestrian activity that was expected to cause flushing. We found a model with additive effects of distance (near, 0-50 m, or far, 50-200 m) and disturbance type (researcher or pedestrian) best explained flock behaviors. The proportion of staging flocks that flushed in response to pedestrians was greatest when pedestrians were within 50 m of the flock. Virtually no flushes were observed in response to researchers, regardless of distance. These results could assist in alleviating concerns that accepted protocols used for intensive band resighting studies on staging seabirds of special conservation status, such as Roseate (Sterna dougallii) and Common (S. hirundo) terns, may have adverse effects. Our framework could be used by others to test the effects of similar research on sensitive species.

Looking Across and Looking Beyond the Knowledge Frontier: Intellectual Distance, Novelty, and Resource Allocation in Science.

PubMed

Boudreau, Kevin J; Guinan, Eva C; Lakhani, Karim R; Riedl, Christoph

2016-10-01

Selecting among alternative projects is a core management task in all innovating organizations. In this paper, we focus on the evaluation of frontier scientific research projects. We argue that the "intellectual distance" between the knowledge embodied in research proposals and an evaluator's own expertise systematically relates to the evaluations given. To estimate relationships, we designed and executed a grant proposal process at a leading research university in which we randomized the assignment of evaluators and proposals to generate 2,130 evaluator-proposal pairs. We find that evaluators systematically give lower scores to research proposals that are closer to their own areas of expertise and to those that are highly novel. The patterns are consistent with biases associated with boundedly rational evaluation of new ideas. The patterns are inconsistent with intellectual distance simply contributing "noise" or being associated with private interests of evaluators. We discuss implications for policy, managerial intervention, and allocation of resources in the ongoing accumulation of scientific knowledge.

Formative Evaluation of the ACSC Distance Learning Program: A Status Study.

ERIC Educational Resources Information Center

MacCuish, Donald A.

2001-01-01

Describes a formative evaluation of the Air Command and Staff College (ACSC) distance learning program, which offers professional military education (PME). Highlights include use of the status study methodology; curriculum development; course design; learning theories; instructional systems design; best practices; and student assessment. (LRW)

Modeling of dialogue regimes of distance robot control

NASA Astrophysics Data System (ADS)

Larkin, E. V.; Privalov, A. N.

2017-02-01

Process of distance control of mobile robots is investigated. Petri-Markov net for modeling of dialogue regime is worked out. It is shown, that sequence of operations of next subjects: a human operator, a dialogue computer and an onboard computer may be simulated with use the theory of semi-Markov processes. From the semi-Markov process of the general form Markov process was obtained, which includes only states of transaction generation. It is shown, that a real transaction flow is the result of «concurrency» in states of Markov process. Iteration procedure for evaluation of transaction flow parameters, which takes into account effect of «concurrency», is proposed.

Electromyographic Patterns during Golf Swing: Activation Sequence Profiling and Prediction of Shot Effectiveness.

PubMed

Verikas, Antanas; Vaiciukynas, Evaldas; Gelzinis, Adas; Parker, James; Olsson, M Charlotte

2016-04-23

This study analyzes muscle activity, recorded in an eight-channel electromyographic (EMG) signal stream, during the golf swing using a 7-iron club and exploits information extracted from EMG dynamics to predict the success of the resulting shot. Muscles of the arm and shoulder on both the left and right sides, namely flexor carpi radialis, extensor digitorum communis, rhomboideus and trapezius, are considered for 15 golf players (∼5 shots each). The method using Gaussian filtering is outlined for EMG onset time estimation in each channel and activation sequence profiling. Shots of each player revealed a persistent pattern of muscle activation. Profiles were plotted and insights with respect to player effectiveness were provided. Inspection of EMG dynamics revealed a pair of highest peaks in each channel as the hallmark of golf swing, and a custom application of peak detection for automatic extraction of swing segment was introduced. Various EMG features, encompassing 22 feature sets, were constructed. Feature sets were used individually and also in decision-level fusion for the prediction of shot effectiveness. The prediction of the target attribute, such as club head speed or ball carry distance, was investigated using random forest as the learner in detection and regression tasks. Detection evaluates the personal effectiveness of a shot with respect to the player-specific average, whereas regression estimates the value of target attribute, using EMG features as predictors. Fusion after decision optimization provided the best results: the equal error rate in detection was 24.3% for the speed and 31.7% for the distance; the mean absolute percentage error in regression was 3.2% for the speed and 6.4% for the distance. Proposed EMG feature sets were found to be useful, especially when used in combination. Rankings of feature sets indicated statistics for muscle activity in both the left and right body sides, correlation-based analysis of EMG dynamics and features derived from the properties of two highest peaks as important predictors of personal shot effectiveness. Activation sequence profiles helped in analyzing muscle orchestration during golf shot, exposing a specific avalanche pattern, but data from more players are needed for stronger conclusions. Results demonstrate that information arising from an EMG signal stream is useful for predicting golf shot success, in terms of club head speed and ball carry distance, with acceptable accuracy. Surface EMG data, collected with a goal to automatically evaluate golf player's performance, enables wearable computing in the field of ambient intelligence and has potential to enhance exercising of a long carry distance drive.

Electromyographic Patterns during Golf Swing: Activation Sequence Profiling and Prediction of Shot Effectiveness

PubMed Central

Verikas, Antanas; Vaiciukynas, Evaldas; Gelzinis, Adas; Parker, James; Olsson, M. Charlotte

2016-01-01

This study analyzes muscle activity, recorded in an eight-channel electromyographic (EMG) signal stream, during the golf swing using a 7-iron club and exploits information extracted from EMG dynamics to predict the success of the resulting shot. Muscles of the arm and shoulder on both the left and right sides, namely flexor carpi radialis, extensor digitorum communis, rhomboideus and trapezius, are considered for 15 golf players (∼5 shots each). The method using Gaussian filtering is outlined for EMG onset time estimation in each channel and activation sequence profiling. Shots of each player revealed a persistent pattern of muscle activation. Profiles were plotted and insights with respect to player effectiveness were provided. Inspection of EMG dynamics revealed a pair of highest peaks in each channel as the hallmark of golf swing, and a custom application of peak detection for automatic extraction of swing segment was introduced. Various EMG features, encompassing 22 feature sets, were constructed. Feature sets were used individually and also in decision-level fusion for the prediction of shot effectiveness. The prediction of the target attribute, such as club head speed or ball carry distance, was investigated using random forest as the learner in detection and regression tasks. Detection evaluates the personal effectiveness of a shot with respect to the player-specific average, whereas regression estimates the value of target attribute, using EMG features as predictors. Fusion after decision optimization provided the best results: the equal error rate in detection was 24.3% for the speed and 31.7% for the distance; the mean absolute percentage error in regression was 3.2% for the speed and 6.4% for the distance. Proposed EMG feature sets were found to be useful, especially when used in combination. Rankings of feature sets indicated statistics for muscle activity in both the left and right body sides, correlation-based analysis of EMG dynamics and features derived from the properties of two highest peaks as important predictors of personal shot effectiveness. Activation sequence profiles helped in analyzing muscle orchestration during golf shot, exposing a specific avalanche pattern, but data from more players are needed for stronger conclusions. Results demonstrate that information arising from an EMG signal stream is useful for predicting golf shot success, in terms of club head speed and ball carry distance, with acceptable accuracy. Surface EMG data, collected with a goal to automatically evaluate golf player’s performance, enables wearable computing in the field of ambient intelligence and has potential to enhance exercising of a long carry distance drive. PMID:27120604

Welding induced residual stress evaluation using laser-generated Rayleigh waves

NASA Astrophysics Data System (ADS)

Ye, Chong; Zhou, Yuanlai; Reddy, Vishnu V. B.; Mebane, Aaron; Ume, I. Charles

2018-04-01

Welding induced residual stress could affect the dimensional stability, fatigue life, and chemical resistance of the weld joints. Ultrasonic method serves as an important non-destructive tool for the residual stress evaluation due to its easy implementation, low cost and wide application to different materials. Residual stress would result in the ultrasonic wave velocity variation, which is the so called acoustoelastic effect. In this paper, Laser/EMAT ultrasonic technique was proposed to experimentally study the relative velocity variation ΔV/V of Rayleigh wave, which has the potential to evaluate surface/subsurface longitudinal residual stress developed during the Gas Metal Arc Welding process. Broad band ultrasonic waves were excited by pulsed Q-Switched Nd: YAG laser. An electromagnetic acoustic transducer (EMAT) attached to the welded plates was used to capture the Rayleigh wave signals propagating along the weld seam direction. Different time of flight measurements were conducted by varying the distance between the weld seam and Rayleigh wave propagating path in the range of 0 to 45 mm. The maximum relative velocity difference was found on the weld seam. With the increasing distance away from the weld seam, the relative velocity difference sharply decreased to negative value. With further increase in distance, the relative velocity difference slowly increased and approached zero. The distribution of relative velocity variations indicates that tensile stress appears in the melted zone as it becomes compressive near the heat-affected zone.

Numerical Analysis of Edge Over Coating and Baffle Effect on Hot-Dip Galvanizing

NASA Astrophysics Data System (ADS)

Bao, Chengren; Kang, Yonglin; Li, Yan

2017-06-01

In hot-dip galvanizing process, air jet wiping control is so crucial to determine the coating thickness and uniformity of the zinc layer on the steel strip. A numerical simulation of gas-jet wiping in hot-dip galvanizing was conducted to minimize the occurrence of edge over coating (EOC). The causes of EOC were identified by contrasting and analyzing the airflow fields on the strip edge with and without a baffle. The factors influencing the airflow field on the strip edge during the change in the gap between the baffle and the strip edge were also analyzed. The effect of the distance between the air knife and the strip was evaluated. Technological parameters with on-site guidance role were obtained by combining them with the actual production to elucidate the role of the baffle in restraining the occurrence of EOC. The uniform distribution of pressure and coating thickness on the strip is achieved when the distance of the baffle from the strip edge is about 0.3 times of the jetting distance.

Refining and defining riverscape genetics: How rivers influence population genetic structure

Treesearch

Chanté D. Davis; Clinton W. Epps; Rebecca L. Flitcroft; Michael A. Banks

2018-01-01

Traditional analysis in population genetics evaluates differences among groups of individuals and, in some cases, considers the effects of distance or potential barriers to gene flow. Genetic variation of organisms in complex landscapes, seascapes, or riverine systems, however, may be shaped by many forces. Recent research has linked habitat heterogeneity and landscape...

Influence of Students' Feedback on the Quality of Adult Higher Distance Education Service Delivery

ERIC Educational Resources Information Center

Oduaran, Akpovire

2017-01-01

The evaluation of a program's compliance with service delivery and features necessary for the attainment of the program's educational objectives, student outcomes and continuous improvement is an important element in program accreditation and continuous improvement process. The study reported in this paper investigated the possible effects of…

Concurrent Development and Cost-Benefit Analysis of Paper-Based and Digitized Instructional Material.

ERIC Educational Resources Information Center

Annand, David

2002-01-01

Describes the simultaneous development of paper-based and digitized versions of a textbook and related instructional material used in an undergraduate, independent study, distance education course at Athabasca University (Canada). Used break-even analysis as an initial evaluation measure to determine cost-effectiveness, and discusses the next…

[Clinical study of the application of non-invasive porcelain veneer to improve the aesthetic effects in maxillary anterior area].

PubMed

Li, Jian-hui; DI, Ping; Hu, Xiu-lian; Qiu, Li-xin; Cui, Hong-yan; Lin, Ye

2010-02-18

To evaluate the clinical results of application of non-invasive porcelain veneer to reduce the black triangle of implant and adjacent teeth and to improve the aesthetic effect in the maxillary anterior area. The study included 10 patients (Male: 4, Female: 6; average age: 41.5) accessioned during May 2007 to August 2009 in Peking University School of Stomatology. The provisional restorations were delivery on implant after 3-6 months healing period of the implant. The non-invasive porcelain veneers were used in the round tip adjacent teeth with gingival recession in the indicated patients. Main measured parameters on the model included horizontal distance and vertical distance. The Horizontal distance refers to the black triangle bottom which is from adjacent surface of the natural teeth to the implant restoration at the gingival level. The vertical distance is from mid-point of the triangle bottom to the contact point. Clinical observed items included bleeding index (BI), integrity of porcelain veneer and degree of satisfaction of the patients. A total of 14 adjacent natural teeth in 10 patients were cemented with porcelain veneer. No porcelain veneer was lost or fracture during follow-up period (range 6 to 27 months, mean of 10.4 months). Mean bleeding index 0-1. The horizontal distance was reduced from (3.1 + or - 0.8) mm before restoration to (1.1 + or - 0.5) mm after restoration. Vertical distance from (5.3 + or - 1.1) mm to (2.9 + or - 0.7) mm. All patients were satisfied with the clinical result. The data and the experience described in this study indicate that improvement of aesthetic effects by using no-invasive porcelain veneer techniques can be a predictable technique for patients with periodontal disease. Further study is needed to determine the long-term result of the technique.

Finally! Distance Education for Library Support Staff.

ERIC Educational Resources Information Center

Rau, Kirk

1998-01-01

Discusses distance undergraduate education programs for paraprofessional librarians and suggests how to evaluate institutions: accreditation, academic program, communication, curriculum, and delivery methods. Highlights the AS degree in Library and Information Technology distance-education program offered by the University of Maine at Augusta.…

[Extramedullary fixation combined with intramedullary fixation in the surgical reduction of sagittal mandibular condylar fractures].

PubMed

Chuanjun, Chen; Xiaoyang, Chen; Jing, Chen

2016-10-01

This study aimed to evaluate the clinical effect of extramedullary fixation combined with intramedullary fixation during the surgical reduction of sagittal mandibular condylar fractures. Twenty-four sagittal fractures of the mandibular condyle in18 patients were fixed by two appliances: intramedullary with one long-screw osteosynthesis or Kirschner wire and extramedullary with one micro-plate. The radiologically-recorded post-operative stability-associated com-plications included the screw/micro-plate loosening, micro-plate twisting, micro-plate fractures, and fragment rotation. The occluding relations, the maximalinter-incisal distances upon mouth opening, and the mandibular deflection upon mouth opening were evaluated based on follow-up clinical examination. Postoperative panoramic X-ray and CT scans showed good repositioning of the fragment, with no redislocation or rotation, no screw/plate loosening, and no plate-twisting or fracture. Clinical examination showed that all patients regained normal mandibular movements, ideal occlusion, and normal maximal inter-incisal distances upon mouth opening. Extramedullary fixation combined with intramedullary fixation is highly recommended for sagittal condylar fractures because of the anti-rotation effect of the fragment and the reasonable place-ment of the fixation appliances.

Analysis of an arched outer-race ball bearing considering centrifugal forces.

NASA Technical Reports Server (NTRS)

Hamrock, B. J.; Anderson, W. J.

1972-01-01

Thrust-load analysis of a 150-mm angular contact ball bearing, taking into account centrifugal forces but omitting gyroscopics, elastohydrodynamics, and thermal effects. A Newton-Raphson method of iteration is used to evaluate the radial and axial projection of the distance between the ball center and the outer raceway groove curvature center. Fatigue life of the bearing is evaluated. Results for life, contact loads, and angles are given for a conventional bearing and two arched bearings.

A Self-Assessment Stereo Capture Model Applicable to the Internet of Things

PubMed Central

Lin, Yancong; Yang, Jiachen; Lv, Zhihan; Wei, Wei; Song, Houbing

2015-01-01

The realization of the Internet of Things greatly depends on the information communication among physical terminal devices and informationalized platforms, such as smart sensors, embedded systems and intelligent networks. Playing an important role in information acquisition, sensors for stereo capture have gained extensive attention in various fields. In this paper, we concentrate on promoting such sensors in an intelligent system with self-assessment capability to deal with the distortion and impairment in long-distance shooting applications. The core design is the establishment of the objective evaluation criteria that can reliably predict shooting quality with different camera configurations. Two types of stereo capture systems—toed-in camera configuration and parallel camera configuration—are taken into consideration respectively. The experimental results show that the proposed evaluation criteria can effectively predict the visual perception of stereo capture quality for long-distance shooting. PMID:26308004

Inspection of the interior surface of cylindrical vessels using optic fiber shearography

NASA Astrophysics Data System (ADS)

Liu, Bin; Wei, Quan; Tu, Jun; Arola, Dwayne D.; Zhang, Dongsheng

2017-09-01

In this study, a shearography system integrated with a coherent fiber-optic illumination and a fiber-optic imaging bundle is presented to inspect the quality of the interior surface of a cylindrical vessel for safety purposes. The specific optical arrangement is designed for the inspection of a certain area at a small working distance. The optical arrangement of the system was assembled and an aluminum honeycomb sample was evaluated to demonstrate the capability of the system. The important relationship between the image quality and the working distance, as well as the field of view, is discussed. The system has been applied for the inspection of the interior surface of a cylindrical vessel. The experimental results suggest that the shearography system integrated with optical and image fibers can effectively minimize the size of the inspection device and be capable of evaluating the interior surface of cylindrical structures.

Effect of soldering techniques and gap distance on tensile strength of soldered Ni-Cr alloy joint.

PubMed

Lee, Sang-Yeob; Lee, Jong-Hyuk

2010-12-01

The present study was intended to evaluate the effect of soldering techniques with infrared ray and gas torch under different gap distances (0.3 mm and 0.5 mm) on the tensile strength and surface porosity formation in Ni-Cr base metal alloy. Thirty five dumbbell shaped Ni-Cr alloy specimens were prepared and assigned to 5 groups according to the soldering method and the gap distance. For the soldering methods, gas torch (G group) and infrared ray (IR group) were compared and each group was subdivided by corresponding gap distance (0.3 mm: G3 and IR3, 0.5 mm: G5, IR5). Specimens of the experimental groups were sectioned in the middle with a diamond disk and embedded in solder blocks according to the predetermined distance. As a control group, 7 specimens were prepared without sectioning or soldering. After the soldering procedure, a tensile strength test was performed using universal testing machine at a crosshead speed 1 mm/min. The proportions of porosity on the fractured surface were calculated on the images acquired through the scanning electronic microscope. Every specimen of G3, G5, IR3 and IR5 was fractured on the solder joint area. However, there was no significant difference between the test groups (P > .05). There was a negative correlation between porosity formation and tensile strength in all the specimens in the test groups (P < .05). There was no significant difference in ultimate tensile strength of joints and porosity formations between the gas-oxygen torch soldering and infrared ray soldering technique or between the gap distance of 0.3 mm and 0.5 mm.

Effect of soldering techniques and gap distance on tensile strength of soldered Ni-Cr alloy joint

PubMed Central

Lee, Sang-Yeob

2010-01-01

PURPOSE The present study was intended to evaluate the effect of soldering techniques with infrared ray and gas torch under different gap distances (0.3 mm and 0.5 mm) on the tensile strength and surface porosity formation in Ni-Cr base metal alloy. MATERIALS AND METHODS Thirty five dumbbell shaped Ni-Cr alloy specimens were prepared and assigned to 5 groups according to the soldering method and the gap distance. For the soldering methods, gas torch (G group) and infrared ray (IR group) were compared and each group was subdivided by corresponding gap distance (0.3 mm: G3 and IR3, 0.5 mm: G5, IR5). Specimens of the experimental groups were sectioned in the middle with a diamond disk and embedded in solder blocks according to the predetermined distance. As a control group, 7 specimens were prepared without sectioning or soldering. After the soldering procedure, a tensile strength test was performed using universal testing machine at a crosshead speed 1 mm/min. The proportions of porosity on the fractured surface were calculated on the images acquired through the scanning electronic microscope. RESULTS Every specimen of G3, G5, IR3 and IR5 was fractured on the solder joint area. However, there was no significant difference between the test groups (P > .05). There was a negative correlation between porosity formation and tensile strength in all the specimens in the test groups (P < .05). CONCLUSION There was no significant difference in ultimate tensile strength of joints and porosity formations between the gas-oxygen torch soldering and infrared ray soldering technique or between the gap distance of 0.3 mm and 0.5 mm. PMID:21264189

Symbolic Numerical Distance Effect Does Not Reflect the Difference between Numbers.

PubMed

Krajcsi, Attila; Kojouharova, Petia

2017-01-01

In a comparison task, the larger the distance between the two numbers to be compared, the better the performance-a phenomenon termed as the numerical distance effect. According to the dominant explanation, the distance effect is rooted in a noisy representation, and performance is proportional to the size of the overlap between the noisy representations of the two values. According to alternative explanations, the distance effect may be rooted in the association between the numbers and the small-large categories, and performance is better when the numbers show relatively high differences in their strength of association with the small-large properties. In everyday number use, the value of the numbers and the association between the numbers and the small-large categories strongly correlate; thus, the two explanations have the same predictions for the distance effect. To dissociate the two potential sources of the distance effect, in the present study, participants learned new artificial number digits only for the values between 1 and 3, and between 7 and 9, thus, leaving out the numbers between 4 and 6. It was found that the omitted number range (the distance between 3 and 7) was considered in the distance effect as 1, and not as 4, suggesting that the distance effect does not follow the values of the numbers predicted by the dominant explanation, but it follows the small-large property association predicted by the alternative explanations.

Enhancing traditional, televised, and videotaped courses with Web-based technologies: a comparison of student satisfaction.

PubMed

Sole, M L; Lindquist, M

2001-01-01

Varied distance learning strategies can be used to deliver nursing courses, including interactive television, videotape, and Web-based approaches. (1) To assess student assess student satisfaction with a critical care elective course offered simultaneously via traditional and distance learning formats in which Web-based strategies were added, and (2) to compare satisfaction of students taking the traditional course versus those taking the class via distance technology. Students (n = 113) who took the course during the spring 1998 and 1999 semesters completed a teacher-constructed evaluation at the end of the semester. Mean ratings on the evaluation were positive. Ratings of interaction, communication with instructor, and facilitation of learning were higher from students who took the traditional course. The application of Web-based technologies may be one factor for the overall course satisfaction. However, it is important to continue to evaluate strategies that work best for students taking courses via distance technology.

Evaluating Usability in a Distance Digital Systems Laboratory Class

ERIC Educational Resources Information Center

Kostaras, N.; Xenos, M.; Skodras, A. N.

2011-01-01

This paper presents the usability evaluation of a digital systems laboratory class offered to distance-learning students. It details the way in which students can participate remotely in such a laboratory, the methodology employed in the usability assessment of the laboratory infrastructure (hardware and software), and also outlines the main…

Integrated management of timber-elk-cattle: interior forests of western North America.

Treesearch

J.W. Thomas; D.A. Leckenby; L. Jack [and others]. Lyon

1988-01-01

The need for and the evaluation of elk-habitat evaluation models are reviewed, and a state-of-the-art example is presented that incorporates distribution of elk-habitat use related to distance from cover/forage edges, distance from roads, cover quality, and forage quantity and quality.

Evaluation of Image Segmentation and Object Recognition Algorithms for Image Parsing

DTIC Science & Technology

2013-09-01

generation of the features from the key points. OpenCV uses Euclidean distance to match the key points and has the option to use Manhattan distance...feature vector includes polarity and intensity information. Final step is matching the key points. In OpenCV , Euclidean distance or Manhattan...the code below is one way and OpenCV offers the function radiusMatch (a pair must have a distance less than a given maximum distance). OpenCV’s

Modeling of urban growth using cellular automata (CA) optimized by Particle Swarm Optimization (PSO)

NASA Astrophysics Data System (ADS)

Khalilnia, M. H.; Ghaemirad, T.; Abbaspour, R. A.

2013-09-01

In this paper, two satellite images of Tehran, the capital city of Iran, which were taken by TM and ETM+ for years 1988 and 2010 are used as the base information layers to study the changes in urban patterns of this metropolis. The patterns of urban growth for the city of Tehran are extracted in a period of twelve years using cellular automata setting the logistic regression functions as transition functions. Furthermore, the weighting coefficients of parameters affecting the urban growth, i.e. distance from urban centers, distance from rural centers, distance from agricultural centers, and neighborhood effects were selected using PSO. In order to evaluate the results of the prediction, the percent correct match index is calculated. According to the results, by combining optimization techniques with cellular automata model, the urban growth patterns can be predicted with accuracy up to 75 %.

Evaluating visual discomfort in stereoscopic projection-based CAVE system with a close viewing distance

NASA Astrophysics Data System (ADS)

Song, Weitao; Weng, Dongdong; Feng, Dan; Li, Yuqian; Liu, Yue; Wang, Yongtian

2015-05-01

As one of popular immersive Virtual Reality (VR) systems, stereoscopic cave automatic virtual environment (CAVE) system is typically consisted of 4 to 6 3m-by-3m sides of a room made of rear-projected screens. While many endeavors have been made to reduce the size of the projection-based CAVE system, the issue of asthenopia caused by lengthy exposure to stereoscopic images in such CAVE with a close viewing distance was seldom tangled. In this paper, we propose a light-weighted approach which utilizes a convex eyepiece to reduce visual discomfort induced by stereoscopic vision. An empirical experiment was conducted to examine the feasibility of convex eyepiece in a large depth of field (DOF) at close viewing distance both objectively and subjectively. The result shows the positive effects of convex eyepiece on the relief of eyestrain.

Tracking modern human population history from linguistic and cranial phenotype

PubMed Central

Reyes-Centeno, Hugo; Harvati, Katerina; Jäger, Gerhard

2016-01-01

Languages and genes arguably follow parallel evolutionary trajectories, descending from a common source and subsequently differentiating. However, although common ancestry is established within language families, it remains controversial whether language preserves a deep historical signal. To address this question, we evaluate the association between linguistic and geographic distances across 265 language families, as well as between linguistic, geographic, and cranial distances among eleven populations from Africa, Asia, and Australia. We take advantage of differential population history signals reflected by human cranial anatomy, where temporal bone shape reliably tracks deep population history and neutral genetic changes, while facial shape is more strongly associated with recent environmental effects. We show that linguistic distances are strongly geographically patterned, even within widely dispersed groups. However, they are correlated predominantly with facial, rather than temporal bone, morphology, suggesting that variation in vocabulary likely tracks relatively recent events and possibly population contact. PMID:27833101

Identifying and mitigating errors in satellite telemetry of polar bears

USGS Publications Warehouse

Arthur, Stephen M.; Garner, Gerald W.; Olson, Tamara L.

1998-01-01

Satellite radiotelemetry is a useful method of tracking movements of animals that travel long distances or inhabit remote areas. However, the logistical constraints that encourage the use of satellite telemetry also inhibit efforts to assess accuracy of the resulting data. To investigate effectiveness of methods that might be used to improve the reliability of these data, we compared 3 sets of criteria designed to select the most plausible locations of polar bears (Ursus maritimus) that were tracked using satellite radiotelemetry in the Bering, Chukchi, East Siberian, Laptev, and Kara seas during 1988-93. We also evaluated several indices of location accuracy. Our results suggested that, although indices could provide information useful in evaluating location accuracy, no index or set of criteria was sufficient to identify all the implausible locations. Thus, it was necessary to examine the data and make subjective decisions about which locations to accept or reject. However, by using a formal set of selection criteria, we simplified the task of evaluating locations and ensured that decisions were made consistently. This approach also enabled us to evaluate biases that may be introduced by the criteria used to identify location errors. For our study, the best set of selection criteria comprised: (1) rejecting locations for which the distance to the nearest other point from the same day was >50 km; (2) determining the highest accuracy code (NLOC) for a particular day and rejecting locations from that day with lesser values; and (3) from the remaining locations for each day, selecting the location closest to the location chosen for the previous transmission period. Although our selection criteria seemed unlikely to bias studies of habitat use or geographic distribution, basing selection decisions on distances between points might bias studies of movement rates or distances. It is unlikely that any set of criteria will be best for all situations; to make efficient use of data and minimize bias, these rules must be tailored to specific study objectives.

Internet-Based Distance Learning in Higher Education.

ERIC Educational Resources Information Center

Hofmann, Donald W.

2002-01-01

Suggests that the effectiveness of Internet-based distance learning has increased with its increased popularity. Looks at the differences between the effectiveness of Internet-based distance learning and traditional methods. Indicates that distance learning is more effective because of the necessity for students to become active learners.…

Maximum nondiffracting propagation distance of aperture-truncated Airy beams

NASA Astrophysics Data System (ADS)

Chu, Xingchun; Zhao, Shanghong; Fang, Yingwu

2018-05-01

Airy beams have called attention of many researchers due to their non-diffracting, self-healing and transverse accelerating properties. A key issue in research of Airy beams and its applications is how to evaluate their nondiffracting propagation distance. In this paper, the critical transverse extent of physically realizable Airy beams is analyzed under the local spatial frequency methodology. The maximum nondiffracting propagation distance of aperture-truncated Airy beams is formulated and analyzed based on their local spatial frequency. The validity of the formula is verified by comparing the maximum nondiffracting propagation distance of an aperture-truncated ideal Airy beam, aperture-truncated exponentially decaying Airy beam and exponentially decaying Airy beam. Results show that the formula can be used to evaluate accurately the maximum nondiffracting propagation distance of an aperture-truncated ideal Airy beam. Therefore, it can guide us to select appropriate parameters to generate Airy beams with long nondiffracting propagation distance that have potential application in the fields of laser weapons or optical communications.

A distance learning model in a physical therapy curriculum.

PubMed

English, T; Harrison, A L; Hart, A L

1998-01-01

In response to the rural health initiative established in 1991, the University of Kentucky has developed an innovative distance learning program of physical therapy instruction that combines classroom lecture and discussion via compressed video technology with laboratory experiences. The authors describe the process of planning, implementing, and evaluating a specific distance learning course in pathomechanics for the professional-level master's-degree physical therapy students at the University of Kentucky. This presentation may serve as a model for teaching distance learning. Descriptions of optimal approaches to preclass preparation, scheduling, course delivery, use of audiovisual aids, use of handout material, and video production are given. Special activities that may enhance or deter the achievement of the learning objectives are outlined, and a problem-solving approach to common problems encountered is presented. An approach to evaluating and comparing course outcomes for the distance learnere is presented. For this particular course, there was no statistically significant difference in the outcome measures utilized to compare the distance learners with the on-site learners.

Positioning for Effectiveness: Applying Marketing Concepts to Distance Education.

ERIC Educational Resources Information Center

Levenburg, Nancy

1997-01-01

Demonstrates how colleges can use distance education to attract and retain a "critical mass" of learners for distance programs. Explores alternative ways to view distance education market opportunities and determine which avenues to pursue. Suggests how to be more effective in all aspects of distance education programs. (13 citations) (YKH)

A position paper of the EFLM Committee on Education and Training and Working Group on Distance Education Programmes/E-Learning: developing an e-learning platform for the education of stakeholders in laboratory medicine.

PubMed

Gruson, Damien; Faure, Gilbert; Gouget, Bernard; Haliassos, Alexandre; Kisikuchin, Darya; Reguengo, Henrique; Topic, Elizabeta; Blaton, Victor

2013-04-01

The progress of information and communication technologies has strongly influenced changes in healthcare and laboratory medicine. E-learning, the learning or teaching through electronic means, contributes to the effective knowledge translation in medicine and healthcare, which is an essential element of a modern healthcare system and for the improvement of patient care. E-learning also represents a great vector for the transfer knowledge into laboratory practice, stimulate multidisciplinary interactions, enhance continuing professional development and promote laboratory medicine. The European Federation of Laboratory Medicine (EFLM) has initiated a distance learning program and the development of a collaborative network for e-learning. The EFLM dedicated working group encourages the organization of distance education programs and e-learning courses as well as critically evaluate information from courses, lectures and documents including electronic learning tools. The objectives of the present paper are to provide some specifications for distance learning and be compatible with laboratory medicine practices.

Optimization of exposure parameters for pediatric chest x-ray imaging

NASA Astrophysics Data System (ADS)

Park, Hye-Suk; Kim, Ye-Seul; Kim, Hee-Joung

2012-03-01

The pediatric patients are more susceptible to the effects of ionizing radiation than adults. Pediatric patients are smaller, more radiosensitive than adult patients and many cannot stand unassisted. Their characteristics affect the method of imaging projection and how dose is optimized. The purpose of this study was to investigate the effect of various technical parameters for the dose optimization in pediatric chest radiological examinations by evaluating effective dose and effective detective quantum efficiency (eDQE) including the scatter radiation from the object, the blur caused by the focal spot, geometric magnification and detector characteristics. For the tube voltages ranging from 40 to 90 kV in 10 kV increments at the focus-to-detector distance of 100, 110, 120, 150, 180 cm, the eDQE was evaluated at same effective dose. The results showed that the eDQE was largest at 60 kVp without and with an anti-scatter grid. Especially, the eDQE was considerably higher without the use of an anti-scatter grid on equivalent effective dose. This indicates that the reducing the scatter radiation did not compensate for the loss of absorbed effective photons in the grid. When the grid is not used the eDQE increased with increasing focus-to-detector distance because of the greater effective modulation transfer function (eMTF) with the lower focal spot blurring. In conclusion, for pediatric patients, the amount of scattered radiation is less, and the amount of grid attenuation increased unnecessary radiation dose.

Evaluation of different delivery modes of an interactive e-learning programme for teaching cultural diversity.

PubMed

Hawthorne, Kamila; Prout, Hayley; Kinnersley, Paul; Houston, Helen

2009-01-01

UK medical schools find it challenging to provide standardised teaching to expanding year intakes. In addition, developing and implementing diversity training can cause difficulties. This paper describes the evaluation of an interactive e-learning programme to raise awareness and understanding of communication difficulties in diversity consultations. The programme was part of an undergraduate portfolio-based community module. Three hundred and two students were assigned to one of three delivery methods--a large group setting, small groups with a facilitator, and as part of distance learning while on community placement. The evaluation included analysis of their coursework marks, a self-completed evaluation questionnaire, and small group discussions. Two hundred and twenty-three students took part in the evaluation. They were able to apply the concepts they learnt to clinical examples from their own experiences. Type of delivery did not affect coursework marks, but students tended to prefer the e-learning as part of a distance learning package. They offered helpful suggestions to improve its complexity and range. The acceptability and utility of this e-learning module both in face to face teaching and remote placement has been demonstrated, and evaluation by the students has provided valuable information for its further development. All medical schools should include some diversity training, and further research should concentrate on the effects of this type of learning on longer term outcomes such as attitude and performance tests. Such tools could reduce demands on staff time in facilitation of small groupwork, and their cost effectiveness could be increased by making them available to other medical schools.

Evaluation of radio-tracking and strip transect methods for determining foraging ranges of Black-Legged Kittiwakes

USGS Publications Warehouse

Ostrand, William D.; Drew, G.S.; Suryan, R.M.; McDonald, L.L.

1998-01-01

We compared strip transect and radio-tracking methods of determining foraging range of Black-legged Kittiwakes (Rissa tridactyla). The mean distance birds were observed from their colony determined by radio-tracking was significantly greater than the mean value calculated from strip transects. We determined that this difference was due to two sources of bias: (1) as distance from the colony increased, the area of available habitat also increased resulting in decreasing bird densities (bird spreading). Consequently, the probability of detecting birds during transect surveys also would decrease as distance from the colony increased, and (2) the maximum distance birds were observed from the colony during radio-tracking exceeded the extent of the strip transect survey. We compared the observed number of birds seen on the strip transect survey to the predictions of a model of the decreasing probability of detection due to bird spreading. Strip transect data were significantly different from modeled data; however, the field data were consistently equal to or below the model predictions, indicating a general conformity to the concept of declining detection at increasing distance. We conclude that radio-tracking data gave a more representative indication of foraging distances than did strip transect sampling. Previous studies of seabirds that have used strip transect sampling without accounting for bird spreading or the effects of study-area limitations probably underestimated foraging range.

SU-G-TeP3-04: Evaluation of the Dose Enhancement with Gold Nanoparticle in Microdosimetry Level Using the Geant4-DNA Toolkit

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, C; Chow, J

Purpose: This study investigated the dose enhancement effect of using gold nanoparticles (GNP) as radiation sensitizers radiated by different photon beam energies. Microdosimetry of photon-irradiated GNP was determined by the Geant4-DNA process in the DNA scale. Methods: Monte Carlo simulation was conducted using the Geant4 toolkit (ver. 10.2). A GNP with different sizes (30, 50, and 100nm diameter sphere) and a DNA were placed in a water cube (1µm{sup 3}). The GNP was irradiated by photon beams with different energies (50, 100, and 150keV) and produced secondary electrons to increase the dose to the DNA. Energy depositions were calculated formore » both with and without GNP and to investigate the dose enhancement effect at the DNA. The distance between the GNP and DNA was varied to optimize the best GNP position to the DNA. The photon beam source was set to 200nm from the GNP in each simulation. Results: It is found that GNP had a dose enhancement effect on kV photon radiations. For Monte Carlo results on different GNP sizes, distances between the GNP and DNA, and photon beam energies, enhancement ratio was found increasing as GNP size increased. The distance between the GNP and DNA affected the result that as distance increased while the dose enhancement ratio decreased. However, the effect of changing distance was not as significant as varying the GNP size. In addition, increasing the photon beam energy also increased the dose enhancement ratio. The largest dose enhancement ratio was found to be 3.5, when the GNP (100nm diameter) irradiated by the 150keV photon beam was set to 80nm from the DNA. Conclusion: Dose enhancement was determined in the DNA with GNP in the microdosimetry scale. It is concluded that the dose enhancement varied with the photon beam energy, GNP size and distance between the GNP and DNA.« less

Effects of off-axis elliptical training on reducing pain and improving knee function in individuals with patellofemoral pain

PubMed Central

Tsai, Liang-Ching; Lee, Song Joo; Yang, Aaron J.; Ren, Yupeng; Press, Joel M.; Zhang, Li-Qun

2014-01-01

Objective To examine whether an off-axis elliptical training program reduces pain and improves knee function in individuals with patellofemoral pain (PFP). Design Controlled laboratory study, pre-test-post-test. Setting University rehabilitation center. Participants Twelve adult subjects with PFP. Interventions Subjects with PFP completed an exercise program consisting of 18 sessions of lower extremity off-axis training using a custom-made elliptical trainer that allows frontal-plane sliding and transverse-plane pivoting of the footplates. Main Outcome Measures Changes in knee pain and function post-training and 6 weeks following training were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee (IKDC) scores. Lower extremity off-axis control was assessed by pivoting and sliding instability, calculated as the root mean square (RMS) of the footplate pivoting angle and sliding distance during elliptical exercise. Subjects’ single-leg hop distance and proprioception in detecting lower extremity pivoting motion were also evaluated. Results Subjects reported significantly greater KOOS and IKDC scores (increased by 12–18 points) and hop distance (increased by 0.2 m) following training. A significant decrease in the pivoting and sliding RMS was also observed following training. Additionally, subjects with PFP demonstrated improved pivoting proprioception when tested under a minimum-weight-bearing position. Conclusions An off-axis elliptical training program was effective in enhancing lower extremity neuromuscular control on the frontal and transverse planes, reducing pain and improving knee function in persons with PFP. PMID:25591131

Evaluation of Motor Control Using Haptic Device

NASA Astrophysics Data System (ADS)

Nuruki, Atsuo; Kawabata, Takuro; Shimozono, Tomoyuki; Yamada, Masafumi; Yunokuchi, Kazutomo

When the kinesthesia and the touch act at the same time, such perception is called haptic perception. This sense has the key role in motor information on the force and position control. The haptic perception is important in the field where the evaluation of the motor control is needed. The purpose of this paper is to evaluate the motor control, perception of heaviness and distance in normal and fatigue conditions using psychophysical experiment. We used a haptic device in order to generate precise force and distance, but the precedent of the evaluation system with the haptic device has been few. Therefore, it is another purpose to examine whether the haptic device is useful as evaluation system for the motor control. The psychophysical quantity of force and distance was measured by two kinds of experiments. Eight healthy subjects participated in this study. The stimulation was presented by haptic device [PHANTOM Omni: SensAble Company]. The subjects compared between standard and test stimulation, and answered it had felt which stimulation was strong. In the result of the psychophysical quantity of force, just noticeable difference (JND) had a significant difference, and point of subjective equality (PSE) was not different between normal and muscle fatigue. On the other hand, in the result of the psychophysical quantity of distance, JND and PSE were not difference between normal and muscle fatigue. These results show that control of force was influenced, but control of distance was not influenced in muscle fatigue. Moreover, these results suggested that the haptic device is useful as the evaluation system for the motor control.

SU-E-I-92: Accuracy Evaluation of Depth Data in Microsoft Kinect.

PubMed

Kozono, K; Aoki, M; Ono, M; Kamikawa, Y; Arimura, H; Toyofuku, F

2012-06-01

Microsoft Kinect has potential for use in real-time patient position monitoring in diagnostic radiology and radiotherapy. We evaluated the accuracy of depth image data and the device-to-device variation in various conditions simulating clinical applications in a hospital. Kinect sensor consists of infrared-ray depth camera and RGB camera. We developed a computer program using OpenNI and OpenCV for measuring quantitative distance data. The program displays depth image obtained from Kinect sensor on the screen, and the cartesian coordinates at an arbitrary point selected by mouse-clicking can be measured. A rectangular box without luster (300 × 198 × 50 mm 3 ) was used as a measuring object. The object was placed on the floor at various distances ranging from 0 to 400 cm in increments of 10 cm from the sensor, and depth data were measured for 10 points on the planar surface of the box. The measured distance data were calibrated by using the least square method. The device-to-device variations were evaluated using five Kinect sensors. There was almost linear relationship between true and measured values. Kinect sensor was unable to measure at a distance of less than 50 cm from the sensor. It was found that distance data calibration was necessary for each sensor. The device-to-device variation error for five Kinect sensors was within 0.46% at the distance range from 50 cm to 2 m from the sensor. The maximum deviation of the distance data after calibration was 1.1 mm at a distance from 50 to 150 cm. The overall average error of five Kinect sensors was 0.18 mm at a distance range of 50 to 150 cm. Kinect sensor has distance accuracy of about 1 mm if each device is properly calibrated. This sensor will be useable for positioning of patients in diagnostic radiology and radiotherapy. © 2012 American Association of Physicists in Medicine.

Effect of scapular external rotation on the axillary nerve during the arthroscopic Latarjet procedure: an anatomical investigation.

PubMed

Reinares, Felipe; Werthel, Jean-David; Moraiti, Constantina; Valenti, Philippe

2017-10-01

The first purpose of this study is to measure the distance between the axillary nerve and the exit point of K-wires placed retrograde through the glenoid in the setting of an arthroscopic Latarjet procedure. The second objective is to evaluate whether manual external rotation of the scapula alters that distance. In seven fresh-frozen specimens, two 2.0-mm K-wires were drilled through the glenoid using an arthroscopic Latarjet retrograde glenoid guide. These were drilled into the glenoid at the 7- and 8-o'clock positions (right shoulders) and at the 4- and 5-o'clock positions (left). K-wires were oriented parallel to the glenoid articular surface and perpendicular to the long superoinferior axis of the glenoid, 7 mm medial to the joint surface. Two independent evaluators measured the distances between the axillary nerve and the exit point of the K-wires in the horizontal plane (AKHS for the superior K-wire and AKHI for the inferior K-wire) and in the vertical plane (AKV). Measurements were taken with the scapula left free and were repeated with the scapula placed at 15° and 30° of external rotation. With the scapula left free, scapular external rotation was 34° ± 2.3°. In this position, the AKHS was 2.5 ± 1.6, 6.3 ± 1.2 mm at 15° of external rotation (ER) and 11.4 ± 1.4 mm at 30° ER. The AKHI distance was 0.37 ± 1.6, 3.4 ± 1.4 and 10.6 ± 2.1 mm, respectively, for the scapula left free, at 15° ER and 30° of ER. The AKV distances were, respectively, 0.12 ± 0.2, 4.9 ± 1.6 and 9.9 ± 1.7 mm. The increase in all distances was statistically significant (p < 0.001). Increasing scapular external rotation significantly increases the distance between the axillary nerve and the exit point of the K-wires, increasing the margin of safety during this procedure. Therefore, increased external rotation of the scapula could be an effective tool to decrease the risk of iatrogenic axillary nerve injury. Cadaveric study, Level V.

Innovations in Doctoral Education: Distance Education Methodology Applied

ERIC Educational Resources Information Center

Bettmann, Joanna; Thompson, Kimberly; Padykula, Nora; Berzoff, Joan

2009-01-01

This study evaluated the impact of a distance education program to meet the practice learning needs of first-year doctoral students. The program, a six-session case-based telephonic seminar, was taught to 19 first-year doctoral students. Evaluation of the program included self-report quantitative and qualitative data gathered pre- and postseminar,…

Online Education Evaluation: What Should We Evaluate?

ERIC Educational Resources Information Center

Hew, Khe Foon; Liu, Shijuan; Martinez, Ray; Bonk, Curt; Lee, Ji-Yeon

2004-01-01

In recent years, Web technologies have helped expand distance education in higher education. Online programs have become widely and generally accepted in many countries. According to the U.S. Department of Education, the number of Institutions of Higher Education (IHEs) offering distance education has increased by one-third since 1994-1995; and 44…

Evaluating ATM Technology for Distance Education in Library and Information Science.

ERIC Educational Resources Information Center

Stanford, Serena W.

1997-01-01

Investigates the impact of asynchronous transfer mode (ATM) technology in an interactive environment providing distance education in library and information science at two San Jose State University (California) sites. The main purpose of the study was to develop a reliable and valid evaluation instrument. Contains 6 tables. (Author/AEF)

Percutaneous irreversible electroporation for breast tissue and breast cancer: safety, feasibility, skin effects and radiologic-pathologic correlation in an animal study.

PubMed

Li, Sheng; Chen, Fei; Shen, Lujun; Zeng, Qi; Wu, Peihong

2016-08-05

To study the safety, feasibility and skin effects of irreversible electroporation (IRE) for breast tissue and breast cancer in animal models. Eight pigs were used in this study. IRE was performed on the left breasts of the pigs with different skin-electrode distances, and the right breasts were used as controls. The electrodes were placed 1-8 mm away from the skin, with an electrode spacing of 1.5-2 cm. Imaging and pathological examinations were performed at specific time points for follow-up evaluation. Vital signs, skin damage, breast tissue changes and ablation efficacy were also closely observed. Eight rabbit models with or without VX2 breast tumor implantations were used to further assess the damage caused by and the repair of thin skin after IRE treatment for breast cancer. Contrast-enhanced ultrasound and elastosonography were used to investigate ablation efficacy and safety. During IRE, the color of the pig breast skin reversibly changed. When the skin-electrode distance was 3 mm, the breast skin clearly changed, becoming white in the center and purple in the surrounding region during IRE. One small purulent skin lesion was detected several days after IRE. When the skin-electrode distance was 5-8 mm, the breast skin became red during IRE. However, the skin architecture was normal when evaluated using gross pathology and hematoxylin-eosin staining. When the skin-electrode distance was 1 mm, skin atrophy and yellow glabrescence occurred in the rabbit breasts after IRE. When the skin-electrode distance was ≥5 mm, there was no skin damage in the rabbit model regardless of breast cancer implantation. After IRE, complete ablation of the targeted breast tissue or cancer was confirmed, and apoptosis was detected in the target tissue and outermost epidermal layer. In the ablated breasts of the surviving animals, complete mammary regeneration with normal skin and hair was observed. Furthermore, no massive fibrosis or mass formation were detected on ultrasound or through hematoxylin-eosin staining. After IRE, the skin architecture was well preserved when the skin-electrode distance was ≥5 mm. Moreover, breast regeneration occurred without mass formation or obvious fibrosis.

Efficient visualization of urban spaces

NASA Astrophysics Data System (ADS)

Stamps, A. E.

2012-10-01

This chapter presents a new method for calculating efficiency and applies that method to the issues of selecting simulation media and evaluating the contextual fit of new buildings in urban spaces. The new method is called "meta-analysis". A meta-analytic review of 967 environments indicated that static color simulations are the most efficient media for visualizing urban spaces. For contextual fit, four original experiments are reported on how strongly five factors influence visual appeal of a street: architectural style, trees, height of a new building relative to the heights of existing buildings, setting back a third story, and distance. A meta-analysis of these four experiments and previous findings, covering 461 environments, indicated that architectural style, trees, and height had effects strong enough to warrant implementation, but the effects of setting back third stories and distance were too small to warrant implementation.

Self-distancing from trauma memories reduces physiological but not subjective emotional reactivity among Veterans with posttraumatic stress disorder.

PubMed

Wisco, Blair E; Marx, Brian P; Sloan, Denise M; Gorman, Kaitlyn R; Kulish, Andrea L; Pineles, Suzanne L

2015-11-01

Self-distancing, or viewing oneself from a third-person perspective, reduces reactivity when analyzing one's feelings. Self-distancing may have important effects among individuals with posttraumatic stress disorder (PTSD), who have heightened emotional and physiological reactivity to trauma memories, but the effects of self-distancing in this group are unclear. We randomly assigned 48 Veterans diagnosed with PTSD to analyze their trauma-related feelings from an immersed (first-person) or distanced (third-person) perspective, and measured physiological and subjective emotional reactivity. Self-distancing during trauma analysis protected against increases in physiological reactivity, such that participants in the immersed condition showed a significant increase in heart rate and skin conductance responses not seen in the distanced condition. However, self-distancing had no effect on self-reported emotional reactivity. Our findings suggest that the effects of self-distancing on subjective emotions may not extend to trauma memories. However, self-distancing during trauma analysis did change physiological reactivity, suggesting at least a short-term benefit for individuals with PTSD.

Evaluation and design of non-lethal laser dazzlers utilizing microcontrollers

NASA Astrophysics Data System (ADS)

Richardson, Keith Jack

Current non-lethal weapons suffer from an inability to meet requirements for uses across many fields and purposes. The safety and effectiveness of these weapons are inadequate. New concepts have provided a weapon utilizing lasers to flashblind a target's visual system. Minimal research and testing have been conducted to investigate the efficiency and safety of these weapons called laser dazzlers. Essentially a laser dazzler is comprised of a laser beam that has been diverged with the use of a lens to expand the beam creating an intensely bright flashlight. All laser dazzlers to date are incapable of adjusting to external conditions automatically. This is important, because the power of these weapons need to change according to distance and light conditions. At long distances, the weapon is rendered useless because the laser beam has become diluted. At near distances, the weapon is too powerful causing permanent damage to the eye because the beam is condensed. Similarly, the eye adapts to brightness by adjusting the pupil size, which effectively limits the amount of light entering the eye. Laser eye damage is determined by the level of irradiance entering the eye. Therefore, a laser dazzler needs the ability to adjust output irradiance to compensate for the distance to the target and ambient light conditions. It was postulated if an innovative laser dazzler design could adjust the laser beam divergence then the irradiance at the eye could be optimized for maximum vision disruption with minimal risk of permanent damage. The young nature of these weapons has lead to the rushed assumptions of laser wavelengths (color) and pulsing frequencies to cause maximum disorientation. Research provided key values of irradiance, wavelength, pulsing frequency and functions for the optical lens system. In order for the laser dazzler to continuously evaluate the external conditions, luminosity and distance sensors were incorporated into the design. A control system was devised to operate the mechanical components meeting calculated values. Testing the conceptual laser dazzlers illustrated the complexities of the system. A set irradiance value could be met at any distance and light condition, although this was accomplished by less than ideal methods. The final design included two lasers and only one optical system. The optical system was only capable of providing constant irradiance of one laser or the other allowing only single laser operation. For dual laser operation, the optical system was calibrated to offset the losses of each laser as distance was changed. Ultimately, this provided a constant combined irradiance with a decreasing green irradiance and increasing red irradiance as distance was increasing. Future work should include enhancements to the mechanical components of the laser dazzler to further refine accuracy. This research was intended to provide a proof of concept and did so successfully.

Speaking Personally--With Marcio Mugnol

ERIC Educational Resources Information Center

Almeida, Luis C.

2014-01-01

Marcio Mugnol is a member of the distance education evaluation team on the Brazilian Ministry of Education (MEC) board. He has delivered concurrent presentations in distance education and is currently researching the advancement of distance education in the Brazilian market. He is a specialist in business management from FGV (Fundação Getulio…

Distance Education and Training Council Constitution and Bylaws. 2012 Edition

ERIC Educational Resources Information Center

Distance Education and Training Council, 2012

2012-01-01

The mission of the Distance Education and Training Council (hereinafter referred to as the Council or DETC) is to promote, by means of standard-setting, evaluation, and consultation processes, the development and maintenance of high educational and ethical standards in education and training programs delivered through distance learning. The…

Occasional Papers in Open and Distance Learning, Number 17.

ERIC Educational Resources Information Center

Donnan, Peter, Ed.; McDonald, Anne, Ed.

These occasional papers focus on open learning and distance education. This volume contains four papers on a variety of topics: bridging courses, issues for researchers in evaluating interactive multimedia, designing study materials to address the special needs of distance students, and faculty attitudes concerning technology. Papers are:…

Evaluation of Hybrid and Distance Education Learning Environments in Spain

ERIC Educational Resources Information Center

Ferrer-Cascales, Rosario; Walker, Scott L.; Reig-Ferrer, Abilio; Fernandez-Pascual, Maria Dolores; Albaladejo-Blazquez, Natalia

2011-01-01

This article describes the adaptation and validation of the "Distance Education Learning Environments Survey" (DELES) for use in investigating the qualities found in distance and hybrid education psycho-social learning environments in Spain. As Europe moves toward post-secondary student mobility, equanimity in access to higher education,…

Examination of University Students' Level of Satisfaction and Readiness for E-Courses and the Relationship between Them

ERIC Educational Resources Information Center

Topal, Arzu Deveci

2016-01-01

The success of a distance education program can be evaluated according to student satisfaction, aside from comprehensive examinations, projects and presentations. The purpose of this research study is to determine both the relationship between e-course satisfaction and online learning readiness by ascertaining student levels, and the effect of the…

The Effects of Divided Attention on Speech Motor, Verbal Fluency, and Manual Task Performance

ERIC Educational Resources Information Center

Dromey, Christopher; Shim, Erin

2008-01-01

Purpose: The goal of this study was to evaluate aspects of the "functional distance hypothesis," which predicts that tasks regulated by brain networks in closer anatomic proximity will interfere more with each other than tasks controlled by spatially distant regions. Speech, verbal fluency, and manual motor tasks were examined to ascertain whether…

Quality and physiological responses of two late-season sweet cherry cultivars 'Lapins' and 'Skeena' to modified atmosphere packaging (MAP) during simulated long distance ocean shipping

USDA-ARS?s Scientific Manuscript database

Flavor loss, skin darkening, pitting, splitting, pedicel browning, and decay are the major quality deteriorations in sweet cherries during storage/shipping. In this research, three modified atmosphere packaging (MAP) liners with varied gas permeability were evaluated for the effect on quality deteri...

Practice and Evaluation of Blended Learning with Cross-Cultural Distance Learning in a Foreign Language Class: Using Mix Methods Data Analysis

ERIC Educational Resources Information Center

Sugie, Satoko; Mitsugi, Makoto

2014-01-01

The Information and Communication Technology (ICT) utilization in Chinese as a "second" foreign language has mainly been focused on Learning Management System (LMS), digital material development, and quantitative analysis of learners' grammatical knowledge. There has been little research that has analyzed the effectiveness of…

Reactions to the Labels "Institutionalized" and "Mentally Retarded" by Retarded and Nonretarded Persons.

ERIC Educational Resources Information Center

Gibbons, Frederick X.; Gibbons, Barbara N.

The effects of labels, "mentally retarded" and "institutionalized" on the evaluations and causal attributions of nonretarded persons, and on the social distance preferences of EMR persons, were assessed. In addition, each group was asked to predict the likelihood of a labeled (mentally retarded) or a nonlabeled target person achieving success at a…

Influence of neighboring particles on the drag of a particle suspended in laminar flows

NASA Astrophysics Data System (ADS)

Roig, Adam Vincent

Understanding particle-fluid flows is very important for the areas of sedimentation in river beds, fluidized bed reactors, and other fields of multiphase flow. The effect of one particle on another in a fluid flow is not very well understood nor does a correlation exist to describe the behavior of the drag coefficient between particles. The use of Proteus was validated by comparison to previous studies to the result obtained through simulations in Proteus, including analysis of the wake structure of a single sphere. Two particles were then analyzed for various Reynolds numbers less than 250 but greater than 5 and for the dimensionless gap of L/D ≥ 2, where L is the distance between the two particle centers and D is the diameter of the particles. Two arrangements were used for simulation, with the particles spaced horizontally or vertically within the fluid flow. Both orientations were evaluated for the effects of the dimensionless gap on the drag coefficient. The wake structure at higher Reynolds numbers were also evaluated for effects due to neighboring particles. A correlation was developed for the case of the horizontal particles at a dimensionless gap, L/D ≥ 2 for the range of Reynolds numbers described. The orientation effect is then studied at a fixed distance for offsets of thirty, forty-five and sixty degrees from the horizontal. Results are also presented to evaluate the effect of the diameter of a neighboring particle. The current results are restricted to the case described in the work. Future studies may build on the current work to extend the work to other effects of neighboring particles and multiple particle influence.

An updated geospatial liquefaction model for global application

USGS Publications Warehouse

Zhu, Jing; Baise, Laurie G.; Thompson, Eric M.

2017-01-01

We present an updated geospatial approach to estimation of earthquake-induced liquefaction from globally available geospatial proxies. Our previous iteration of the geospatial liquefaction model was based on mapped liquefaction surface effects from four earthquakes in Christchurch, New Zealand, and Kobe, Japan, paired with geospatial explanatory variables including slope-derived VS30, compound topographic index, and magnitude-adjusted peak ground acceleration from ShakeMap. The updated geospatial liquefaction model presented herein improves the performance and the generality of the model. The updates include (1) expanding the liquefaction database to 27 earthquake events across 6 countries, (2) addressing the sampling of nonliquefaction for incomplete liquefaction inventories, (3) testing interaction effects between explanatory variables, and (4) overall improving model performance. While we test 14 geospatial proxies for soil density and soil saturation, the most promising geospatial parameters are slope-derived VS30, modeled water table depth, distance to coast, distance to river, distance to closest water body, and precipitation. We found that peak ground velocity (PGV) performs better than peak ground acceleration (PGA) as the shaking intensity parameter. We present two models which offer improved performance over prior models. We evaluate model performance using the area under the curve under the Receiver Operating Characteristic (ROC) curve (AUC) and the Brier score. The best-performing model in a coastal setting uses distance to coast but is problematic for regions away from the coast. The second best model, using PGV, VS30, water table depth, distance to closest water body, and precipitation, performs better in noncoastal regions and thus is the model we recommend for global implementation.

Seeing an Embodied Virtual Hand is Analgesic Contingent on Colocation.

PubMed

Nierula, Birgit; Martini, Matteo; Matamala-Gomez, Marta; Slater, Mel; Sanchez-Vives, Maria V

2017-06-01

Seeing one's own body has been reported to have analgesic properties. Analgesia has also been described when seeing an embodied virtual body colocated with the real one. However, there is controversy regarding whether this effect holds true when seeing an illusory-owned body part, such as during the rubber-hand illusion. A critical difference between these paradigms is the distance between the real and surrogate body part. Colocation of the real and surrogate arm is possible in an immersive virtual environment, but not during illusory ownership of a rubber arm. The present study aimed at testing whether the distance between a real and a virtual arm can explain such differences in terms of pain modulation. Using a paradigm of embodiment of a virtual body allowed us to evaluate heat pain thresholds at colocation and at a 30-cm distance between the real and the virtual arm. We observed a significantly higher heat pain threshold at colocation than at a 30-cm distance. The analgesic effects of seeing a virtual colocated arm were eliminated by increasing the distance between the real and the virtual arm, which explains why seeing an illusorily owned rubber arm does not consistently result in analgesia. These findings are relevant for the use of virtual reality in pain management. Looking at a virtual body has analgesic properties similar to looking at one's real body. We identify the importance of colocation between a real and a surrogate body for this to occur and thereby resolve a scientific controversy. This information is useful for exploiting immersive virtual reality in pain management. Copyright © 2017. Published by Elsevier Inc.

Maxillary tridimensional changes after slow expansion with leaf expander in a sample of growing patients: a pilot study.

PubMed

Lanteri, V; Gianolio, A; Gualandi, G; Beretta, M

2018-03-01

The aim of this study is to evaluate the dento-alveolar effects of slow maxillary expansion using the Leaf Expander in a sample of growing patients with maxillary transverse deficiency, unilateral cross bite and mandibular shift. The study included 10 patients, 3 male and 7 female (mean age 7.5 + 7 months), treated with Leaf Expander anchored on the upper deciduous teeth. Digital models were obtained by a lab scan of the pvs impressions at the beginning of the therapy (T1) and at the removal of the palatal expander (T2). Five parameters were measured: 1) the distance between the first upper permanent molars; 2) the distance between the upper second deciduous molars; 3) the distance between the upper canine cusps 4) the distance between the first lower permanent molars; 5) the distance of the lower canine cusps. In all patients complete correction of posterior crossbite was achieved on average in 4 months, with a spontaneous expansion of the upper first permanent molars. Significant increases in the dento-alveolar transversal diameters were obtained. Increases were also observed in the anterior mandibular arch diameter (+ 1 mm). These findings suggest that slow maxillary expansion using Leaf Expander appliance could be a reasonable alternative to conventional maxillary expansion therapy in the early mixed dentition.

Soybean yield in relation to distance from the Itaipu reservoir

NASA Astrophysics Data System (ADS)

de Faria, Rogério Teixeira; Junior, Ruy Casão; Werner, Simone Silmara; Junior, Luiz Antônio Zanão; Hoogenboom, Gerrit

2016-07-01

Crops close to small water bodies may exhibit changes in yield if the water mass causes significant changes in the microclimate of areas near the reservoir shoreline. The scientific literature describes this effect as occurring gradually, with higher intensity in the sites near the shoreline and decreasing intensity with distance from the reservoir. Experiments with two soybean cultivars were conducted during four crop seasons to evaluate soybean yield in relation to distance from the Itaipu reservoir and determine the effect of air temperature and water availability on soybean crop yield. Fifteen experimental sites were distributed in three transects perpendicular to the Itaipu reservoir, covering an area at approximately 10 km from the shoreline. The yield gradient between the site closest to the reservoir and the sites farther away in each transect did not show a consistent trend, but varied as a function of distance, crop season, and cultivar. This finding indicates that the Itaipu reservoir does not affect the yield of soybean plants grown within approximately 10 km from the shoreline. In addition, the variation in yield among the experimental sites was not attributed to thermal conditions because the temperature was similar within transects. However, the crop water availability was responsible for higher differences in yield among the neighboring experimental sites related to water stress caused by spatial variability in rainfall, especially during the soybean reproductive period in January and February.

Analytic processing of distance.

PubMed

Dopkins, Stephen; Galyer, Darin

2018-01-01

How does a human observer extract from the distance between two frontal points the component corresponding to an axis of a rectangular reference frame? To find out we had participants classify pairs of small circles, varying on the horizontal and vertical axes of a computer screen, in terms of the horizontal distance between them. A response signal controlled response time. The error rate depended on the irrelevant vertical as well as the relevant horizontal distance between the test circles with the relevant distance effect being larger than the irrelevant distance effect. The results implied that the horizontal distance between the test circles was imperfectly extracted from the overall distance between them. The results supported an account, derived from the Exemplar Based Random Walk model (Nosofsky & Palmieri, 1997), under which distance classification is based on the overall distance between the test circles, with relevant distance being extracted from overall distance to the extent that the relevant and irrelevant axes are differentially weighted so as to reduce the contribution of irrelevant distance to overall distance. The results did not support an account, derived from the General Recognition Theory (Ashby & Maddox, 1994), under which distance classification is based on the relevant distance between the test circles, with the irrelevant distance effect arising because a test circle's perceived location on the relevant axis depends on its location on the irrelevant axis, and with relevant distance being extracted from overall distance to the extent that this dependency is absent. Copyright © 2017 Elsevier B.V. All rights reserved.

The facile synthesis of a chitosan Cu(II) complex by solution plasma process and evaluation of their antioxidant activities.

PubMed

Ma, Fengming; Li, Pu; Zhang, Baiqing; Wang, Zhenyu

2017-10-01

Synthesis of chitosan-Cu(II) complex by solution plasma process (SPP) irradiation was investigated. The effects of the distance between the electrodes, initial Cu(II) concentration, and initial pH on the Cu(II) adsorption capacity were evaluated. The results showed that narrower distance between the electrodes, higher initial Cu(II) concentration and higher initial pH (at pH<6) were favourable for the adsorption capacity of Cu(II). Characterization of the chitosan-Cu(II) complex by ultraviolet-visible (UV-vis), fourier transform infrared (FT-IR) and electron spin resonance (ESR) spectroscopy revealed that the main structure of chitosan was not changed after irradiation. Thermogravimetry (TG) analysis indicated that Cu(II) ions were well incorporated into the chitosan. The antioxidant activity of the chitosan-Cu(II) complex was evaluated by DPPH, ABTS, and reducing power assays. The chitosan-Cu(II) complex exhibited greater antioxidant activity than the original chitosan. Thus, SPP could be used for preparation of chitosan-Cu(II) complexes. Copyright © 2017. Published by Elsevier B.V.

Statistical characterization of spatial patterns of rainfall cells in extratropical cyclones

NASA Astrophysics Data System (ADS)

Bacchi, Baldassare; Ranzi, Roberto; Borga, Marco

1996-11-01

The assumption of a particular type of distribution of rainfall cells in space is needed for the formulation of several space-time rainfall models. In this study, weather radar-derived rain rate maps are employed to evaluate different types of spatial organization of rainfall cells in storms through the use of distance functions and second-moment measures. In particular the spatial point patterns of the local maxima of rainfall intensity are compared to a completely spatially random (CSR) point process by applying an objective distance measure. For all the analyzed radar maps the CSR assumption is rejected, indicating that at the resolution of the observation considered, rainfall cells are clustered. Therefore a theoretical framework for evaluating and fitting alternative models to the CSR is needed. This paper shows how the "reduced second-moment measure" of the point pattern can be employed to estimate the parameters of a Neyman-Scott model and to evaluate the degree of adequacy to the experimental data. Some limitations of this theoretical framework, and also its effectiveness, in comparison to the use of scaling functions, are discussed.

Locality of Area Coverage on Digital Acoustic Communication in Air using Differential Phase Shift Keying

NASA Astrophysics Data System (ADS)

Mizutani, Keiichi; Ebihara, Tadashi; Wakatsuki, Naoto; Mizutani, Koichi

2009-07-01

We experimentally evaluate the locality of digital acoustic communication in air. Digital acoustic communication in air is suitable for a small cell system, because acoustic waves have a short propagation distance in air. In this study, optimal cell size is experimentally evaluated. Each base station (BS) transmits different commands. In our experiment, differential phase shift keying (DPSK), especially binary DPSK (DBPSK), is adopted as a modulation and demodulation scheme. The evaluated system consists of a personal computer (PC), a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), a loud speaker (SP), a microphone (MIC), and transceiver software. All experiments are performed in an anechoic room. The cell size of the transmitter can be limited under low signal-to-noise ratio (SNR) condition. If another transmitter works, cell size is limited by the effect of the interference from that transmitter. The cell size-to-distance ratio of transmitter A to transmitter B is 37.5%, if cell edge bit-error-rate (BER) is taken as 10-3.

Evaluation of Interhandle Distance During Pushing and Pulling of a Four-Caster Cart for Upper Limb Exertion.

PubMed

Ohnishi, Akihiro; Takanokura, Masato; Sugama, Atsushi

2016-09-01

This study examined the relationship between interhandle distances and upper limb exertion during simply pushing and pulling of a cart with four swivel wheels, defined by a roll box pallet (RBP) in a Japanese industrial standard. Six healthy young male participants were asked to push and pull an RBP at a distance of 5.2 m under six conditions corresponding to different interhandle distances (40 cm, 60 cm, and 80 cm) and weights (130 kg and 250 kg). The upper limb exertion was studied by shoulder abduction and flexion, and elbow flexion, as well as surface electromyogram (EMG) in shoulder extensor, and elbow flexor and extensor. Participants were required to provide subjective evaluations on operability after each trial. Subjective operability indicated that a narrower interhandle distance had a better operability for pushing. Interhandle distance was also related to upper limb exertion especially for pushing. A narrow interhandle distance caused smaller shoulder adduction but larger elbow flexion. The normalized EMG data revealed that muscular activity became smaller with a narrow interhandle distance in shoulder extensor. During the pulling task, elbow flexion was smaller at a narrow interhandle distance, although subjective operability and normalized EMG were not significantly varied. A wider interhandle distance, such as 80 cm, was not suitable in the forwardbackward movement of the RBP. Therefore, this study concluded that an interhandle distance of 40 cm would be suitable for pushing and pulling an RBP to protect the workers' hands against the risk of injury by installing inner handles.

Effect of Fluoride-Releasing Adhesive Systems on the Mechanical Properties of Eroded Dentin.

PubMed

Guedes, Ana Paula Albuquerque; Moda, Mariana Dias; Suzuki, Thaís Yumi Umeda; Godas, André Gustavo de Lima; Sundfeld, Renato Herman; Briso, André Luiz Fraga; Santos, Paulo Henrique dos

2016-01-01

The aim of the study was to evaluate the effect of erosive pH cycling with solutions that simulate dental erosion on Martens hardness (HMV) and elastic modulus (Eit) of dentin restored with fluoride-releasing adhesive systems. Twenty-seven bovine dentin slabs were restored with three adhesive systems: Adper Single Bond 2 total-etch adhesive system, One Up Bond F and Clearfil SE Protect fluoride-containing self-etching adhesive systems. The restorations were made with Filtek Z250. The HMV and Eit values at distances of 10, 30, 50 and 70 µm from the interface were evaluated using a dynamic ultra microhardness tester before and after immersion in deionized water, citric acid and hydrochloric acid (n=9). Data were submitted to repeated-measures ANOVA and Fisher's PLSD tests (=0.05). After erosive cycling, HMV values of dentin decreased in all groups. For dentin restored with Adper Single Bond 2, the lowest values were found closer to the hybrid layer, while for One Up Bond F and Clearfil SE Protect, the values remained unaltered at all distances. For dentin restored with fluoride-releasing adhesive systems, a decrease in Eit was found, but after 30 µm this difference was not significant. The acid substances were able to alter HMV and Eit of the underlying dentin. For fluoride-releasing adhesives, the greater the distance from bonded interface, the lower the Eit values. The fluoride in One Up Bond F and Clearfil SE Protect was able to protect the underlying dentin closer to the materials. In this way, the fluoride from adhesive systems could have some positive effect in the early stages of erosive lesions.

Assessment of the Effectiveness of Internet-Based Distance Learning through the VClass e-Education Platform

ERIC Educational Resources Information Center

Pukkaew, Chadchadaporn

2013-01-01

This study assesses the effectiveness of internet-based distance learning (IBDL) through the VClass live e-education platform. The research examines (1) the effectiveness of IBDL for regular and distance students and (2) the distance students' experience of VClass in the IBDL course entitled Computer Programming 1. The study employed the common…

Use of the Advanced Communications Technology Satellite to Promote International Distance Education Programs for Georgetown University

NASA Technical Reports Server (NTRS)

Bradley, Harold; Kauffman, Amy

1996-01-01

Georgetown's distance education program is designed to demonstrate to faculty and administrators the feasibility and desirability of using two-way video transmission for international education. These programs will extend the reach of Georgetown's educational offerings; enrich the curriculum and content of Georgetown's offerings by interaction with institutions in other nations; enhance the world view of the School of Business Administration; enable Georgetown to share its resources with other institutions outside of the United States; and promote Commerce within the Americas. The primary reason for this pilot program is to evaluate the effectiveness and economic viability of offering academic courses and Small Business Development training.

Mega-fire Recovery in Dry Conifer Forests of the Interior West

NASA Astrophysics Data System (ADS)

Malone, S. L.; Fornwalt, P.; Chambers, M. E.; Battaglia, M.

2015-12-01

Wildfire is a complex landscape process with great uncertainty in whether trends in size and severity are shifting trajectories for ecosystem recovery that are outside of the historical range of variability. Considering that wildfire size and severity is likely to increase into the future with a drier climate, it is important that we understand wildfire effects and ecosystem recovery. To evaluate how ecosystems recover from wildfire we measured spatial patterns in regeneration and mapped tree refugia within mega-fire perimeters (Hayman, Jasper, Bobcat, and Grizzly Gulch) in ponderosa pine (Pinus ponderosa) dominated forest. On average, high severity fire effects accounted for > 15% of burned area and increased with fire size. Areas with high severity fire effects contained 1 - 15% tree refugia cover, compared to 37 - 70% observed in low severity areas . Large high severity patches with low coverage of tree refugia, were more frequent in larger fires and regeneration distances required to initiate forest recovery far exceeded 1.5 canopy height or 200 m, distances where the vast majority of regeneration is likely to arise. Using a recovery model driven by distance, we estimate recovery times between 300 to > 1000 years for these mega-fires. In Western dry conifer forests, large patches of stand replacing fire are likely to lead to uneven aged forest and very long recovery times.

Integrated Testing, Simulation and Analysis of Electric Drive Options for Medium-Duty Parcel Delivery Vehicles: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramroth, L. A.; Gonder, J.; Brooker, A.

2012-09-01

The National Renewable Energy Laboratory verified diesel-conventional and diesel-hybrid parcel delivery vehicle models to evaluate petroleum reduction and cost implications of plug-in hybrid gasoline and diesel variants. These variants are run on a field-data-derived design matrix to analyze the effects of drive cycle, distance, battery replacements, battery capacity, and motor power on fuel consumption and lifetime cost. Two cost scenarios using fuel prices corresponding to forecasted highs for 2011 and 2030 and battery costs per kilowatt-hour representing current and long-term targets compare plug-in hybrid lifetime costs with diesel conventional lifetime costs. Under a future cost scenario of $100/kWh battery energymore » and $5/gal fuel, plug-in hybrids are cost effective. Assuming a current cost of $700/kWh and $3/gal fuel, they rarely recoup the additional motor and battery cost. The results highlight the importance of understanding the application's drive cycle, daily driving distance, and kinetic intensity. For instances in the current-cost scenario where the additional plug-in hybrid cost is regained in fuel savings, the combination of kinetic intensity and daily distance travelled does not coincide with the usage patterns observed in the field data. If the usage patterns were adjusted, the hybrids could become cost effective.« less

Learning and navigation of hornets: role of the various light perceiving organs.

PubMed

Kirshboim, S; Ishay, J S

2001-01-01

The present study reports on experiments carried out on workers of Vespa orientalis (Hymenoptera, Vespinae). The experiments involved: learning of the workers upon their breeding box, evaluation of their ability to navigate back to the breeding box from ever increasing distances, and the effect which masking the various light perceiving organs has on the homing flight of hornets. The test hornets were removed from their breeding box to which they became accustomed and then released at gradually increasing distances from it (100 to 1000 meters) so as to assess their ability to return home. The group of hornets returning from a given distance was on the next day released at a greater distance, and so forth, and their homing capability was then compared between regular control groups and hornets that were coated with masking paint in various light-perceiving regions such as the clypeus, frons, ocelli and ommatidia on the head or segments 3 or 4 of the gaster, the whole gaster or various combinations of the two (head and gaster). It was found that in all the groups combined (test + various controls) only about 44% of hornets released at a distance of 100 meters from the breeding box, found their way home. The percentage of homing hornets diminished with increasing distance from home and generally they responded in accordance with the formula: S(d)=exp(dp/beta), where d=distance; S(d)=the proportion of hornets expected to return from d; P=the shape parameter of the distribution: beta=the 'scale' parameter of the distribution. Percentage of successfully homing hornets was significantly larger in control hornets than in treated ones only at a release distance of 1000 meters.

A study on quantitative analysis of exposure dose caused by patient depending on time and distance in nuclear medicine examination

NASA Astrophysics Data System (ADS)

Kim, H. S.; Cho, J. H.; Shin, S. G.; Dong, K. R.; Chung, W. K.; Chung, J. E.

2013-01-01

This study evaluated possible actions that can help protect against and reduce radiation exposure by measuring the exposure dose for each type of isotope that is used frequently in nuclear medicine before performing numerical analysis of the effective half-life based on the measurement results. From July to August in 2010, the study targeted 10, 6 and 5 people who underwent an 18F-FDG (fludeoxyglucose) positron emission tomography (PET) scan, 99mTc-HDP bone scan, and 201Tl myocardial single-photon emission computed tomography (SPECT) scan, respectively, in the nuclear medicine department. After injecting the required medicine into the subjects, a survey meter was used to measure the dose depending on the distance from the heart and time elapsed. For the 18F-FDG PET scan, the dose decreased by approximately 66% at 90 min compared to that immediately after the injection and by 78% at a distance of 1 m compared to that at 0.3 m. In the 99mTc-HDP bone scan, the dose decreased by approximately 71% in 200 min compared to that immediately after the injection and by approximately 78% at a distance of 1 m compared to that at 0.3 m. In the 201Tl myocardial SPECT scan, the dose decreased by approximately 30% in 250 min compared to that immediately after the injection and by approximately 55% at a distance of 1 m compared to that at 0.3 m. In conclusion, the dose decreases by a large margin depending on the distance and time. In conclusion, this study measured the exposure doses by isotopes, distance from the heart and exposure time, and found that the doses were reduced significantly according the distance and the time.

[Multifactorial method for assessing the physical work capacity of mice].

PubMed

Dubovik, B V; Bogomazov, S D

1987-01-01

Based on the swimming test according to Kiplinger, in experiments on (CBA X C57BL)F1 mice there were elaborated criteria for animal performance evaluation in the process of repeated swimming of a standard distance thus measuring power, volume of work and rate of the fatigue development in relative units. From the study of effects of sydnocarb, bemethyl and phenazepam on various parameters of physical performance of mice a conclusion was made that the proposed method provides a more informative evaluation of the pharmacological effect on physical performance of animals as compared to the methods based on the record of time of performing the load.

Influence of viewing distance and size of tv on visual fatigue and feeling of involvement.

PubMed

Sakamoto, Kiyomi; Asahara, Shigeo; Yamashita, Kuniko; Okada, Akira

2012-12-01

Using physiological and psychological measurements, we carried out experiments to investigate the influence of viewing distance and TV screen size on visual fatigue and feeling of involvement using 17-inch, 42-inch and 65-inch displays. The experiment was an ordinary viewing test with the content similar to everyday TV programs for one hour including scenery, sport, drama, etc., with commercials sandwiched in between. The number of participants was 16 (8 persons aged 21-31, and 8 persons aged 50-70) for each display size. In all, 48 participants viewed 3 display sizes. In our physiological evaluation, CFF (critical flicker fusion frequency), blink rate and a sympathetic nerve activity index were used; and in the psychological evaluation, questionnaires and interviews were employed. Our results, based on physiological and psychological measurements, suggest the opti- mum viewing distance to be around 165-220 cm, irrespective of screen size. Our evaluations, which are based on optimum viewing distance for minimal visual fatigue and a closer feeling of involvement, might therefore not agree with the currently recommended viewing distance, which is defined as 2 or 3 times the display's height.

Quality of core collections for effective utilisation of genetic resources review, discussion and interpretation.

PubMed

Odong, T L; Jansen, J; van Eeuwijk, F A; van Hintum, T J L

2013-02-01

Definition of clear criteria for evaluation of the quality of core collections is a prerequisite for selecting high-quality cores. However, a critical examination of the different methods used in literature, for evaluating the quality of core collections, shows that there are no clear guidelines on the choices of quality evaluation criteria and as a result, inappropriate analyses are sometimes made leading to false conclusions being drawn regarding the quality of core collections and the methods to select such core collections. The choice of criteria for evaluating core collections appears to be based mainly on the fact that those criteria have been used in earlier publications rather than on the actual objectives of the core collection. In this study, we provide insight into different criteria used for evaluating core collections. We also discussed different types of core collections and related each type of core collection to their respective evaluation criteria. Two new criteria based on genetic distance are introduced. The consequences of the different evaluation criteria are illustrated using simulated and experimental data. We strongly recommend the use of the distance-based criteria since they not only allow the simultaneous evaluation of all variables describing the accessions, but they also provide intuitive and interpretable criteria, as compared with the univariate criteria generally used for the evaluation of core collections. Our findings will provide genebank curators and researchers with possibilities to make informed choices when creating, comparing and using core collections.

Voronoi distance based prospective space-time scans for point data sets: a dengue fever cluster analysis in a southeast Brazilian town

PubMed Central

2011-01-01

Background The Prospective Space-Time scan statistic (PST) is widely used for the evaluation of space-time clusters of point event data. Usually a window of cylindrical shape is employed, with a circular or elliptical base in the space domain. Recently, the concept of Minimum Spanning Tree (MST) was applied to specify the set of potential clusters, through the Density-Equalizing Euclidean MST (DEEMST) method, for the detection of arbitrarily shaped clusters. The original map is cartogram transformed, such that the control points are spread uniformly. That method is quite effective, but the cartogram construction is computationally expensive and complicated. Results A fast method for the detection and inference of point data set space-time disease clusters is presented, the Voronoi Based Scan (VBScan). A Voronoi diagram is built for points representing population individuals (cases and controls). The number of Voronoi cells boundaries intercepted by the line segment joining two cases points defines the Voronoi distance between those points. That distance is used to approximate the density of the heterogeneous population and build the Voronoi distance MST linking the cases. The successive removal of edges from the Voronoi distance MST generates sub-trees which are the potential space-time clusters. Finally, those clusters are evaluated through the scan statistic. Monte Carlo replications of the original data are used to evaluate the significance of the clusters. An application for dengue fever in a small Brazilian city is presented. Conclusions The ability to promptly detect space-time clusters of disease outbreaks, when the number of individuals is large, was shown to be feasible, due to the reduced computational load of VBScan. Instead of changing the map, VBScan modifies the metric used to define the distance between cases, without requiring the cartogram construction. Numerical simulations showed that VBScan has higher power of detection, sensitivity and positive predicted value than the Elliptic PST. Furthermore, as VBScan also incorporates topological information from the point neighborhood structure, in addition to the usual geometric information, it is more robust than purely geometric methods such as the elliptic scan. Those advantages were illustrated in a real setting for dengue fever space-time clusters. PMID:21513556

Maternal effects on anogenital distance in a wild marmot population.

PubMed

Fouqueray, Timothée D; Blumstein, Daniel T; Monclús, Raquel; Martin, Julien G A

2014-01-01

In mammals, prenatal exposure to sex steroid hormones may have profound effects on later behavior and fitness and have been reported under both laboratory and field conditions. Anogenital distance is a non-invasive measure of prenatal exposure to sex steroid hormones. While we know that intra-uterine position and litter sex ratio influence anogenital distance, there are other, heretofore unstudied, factors that could influence anogenital distance, including maternal effects. We capitalized on a long-term study of wild yellow-bellied marmots (Marmota flaviventris) to study the importance of maternal effects on explaining variation in anogenital distance and found significant effects. The strength of these effects varied annually. Taken together, our data highlights the strong variability due to environmental effects, and illustrates the importance of additive genetic and maternal genetic effects on neonatal anogenital distance. We suspect that, as others apply recently popularised quantitative genetic techniques to study free-living populations, such effects will be identified in other systems.

Maternal Effects on Anogenital Distance in a Wild Marmot Population

PubMed Central

Fouqueray, Timothée D.; Blumstein, Daniel T.; Monclús, Raquel; Martin, Julien G. A.

2014-01-01

In mammals, prenatal exposure to sex steroid hormones may have profound effects on later behavior and fitness and have been reported under both laboratory and field conditions. Anogenital distance is a non-invasive measure of prenatal exposure to sex steroid hormones. While we know that intra-uterine position and litter sex ratio influence anogenital distance, there are other, heretofore unstudied, factors that could influence anogenital distance, including maternal effects. We capitalized on a long-term study of wild yellow-bellied marmots (Marmota flaviventris) to study the importance of maternal effects on explaining variation in anogenital distance and found significant effects. The strength of these effects varied annually. Taken together, our data highlights the strong variability due to environmental effects, and illustrates the importance of additive genetic and maternal genetic effects on neonatal anogenital distance. We suspect that, as others apply recently popularised quantitative genetic techniques to study free-living populations, such effects will be identified in other systems. PMID:24651864

Assessing opportunities for physical activity in the built environment of children: interrelation between kernel density and neighborhood scale.

PubMed

Buck, Christoph; Kneib, Thomas; Tkaczick, Tobias; Konstabel, Kenn; Pigeot, Iris

2015-12-22

Built environment studies provide broad evidence that urban characteristics influence physical activity (PA). However, findings are still difficult to compare, due to inconsistent measures assessing urban point characteristics and varying definitions of spatial scale. Both were found to influence the strength of the association between the built environment and PA. We simultaneously evaluated the effect of kernel approaches and network-distances to investigate the association between urban characteristics and physical activity depending on spatial scale and intensity measure. We assessed urban measures of point characteristics such as intersections, public transit stations, and public open spaces in ego-centered network-dependent neighborhoods based on geographical data of one German study region of the IDEFICS study. We calculated point intensities using the simple intensity and kernel approaches based on fixed bandwidths, cross-validated bandwidths including isotropic and anisotropic kernel functions and considering adaptive bandwidths that adjust for residential density. We distinguished six network-distances from 500 m up to 2 km to calculate each intensity measure. A log-gamma regression model was used to investigate the effect of each urban measure on moderate-to-vigorous physical activity (MVPA) of 400 2- to 9.9-year old children who participated in the IDEFICS study. Models were stratified by sex and age groups, i.e. pre-school children (2 to <6 years) and school children (6-9.9 years), and were adjusted for age, body mass index (BMI), education and safety concerns of parents, season and valid weartime of accelerometers. Association between intensity measures and MVPA strongly differed by network-distance, with stronger effects found for larger network-distances. Simple intensity revealed smaller effect estimates and smaller goodness-of-fit compared to kernel approaches. Smallest variation in effect estimates over network-distances was found for kernel intensity measures based on isotropic and anisotropic cross-validated bandwidth selection. We found a strong variation in the association between the built environment and PA of children based on the choice of intensity measure and network-distance. Kernel intensity measures provided stable results over various scales and improved the assessment compared to the simple intensity measure. Considering different spatial scales and kernel intensity methods might reduce methodological limitations in assessing opportunities for PA in the built environment.

Enhancing Research Capacity for Global Health: Evaluation of a Distance-Based Program for International Study Coordinators

ERIC Educational Resources Information Center

Wilson, Lynda Law; Rice, Marti; Jones, Carolynn T.; Joiner, Cynthia; LaBorde, Jennifer; McCall, Kimberly; Jester, Penelope M.; Carter, Sheree C.; Boone, Chrissy; Onwuzuligbo, Uzoma; Koneru, Alaya

2013-01-01

Introduction: Due to the increasing number of clinical trials conducted globally, there is a need for quality continuing education for health professionals in clinical research manager (CRM) roles. This article describes the development, implementation, and evaluation of a distance-based continuing education program for CRMs working outside the…

Distance Learning Success--A Perspective from Socio-Technical Systems Theory

ERIC Educational Resources Information Center

Wang, Jianfeng; Solan, David; Ghods, Abe

2010-01-01

With widespread adoption of computer-based distance education as a mission-critical component of the institution's educational program, the need for evaluation has emerged. In this research, we aim to expand on the systems approach by offering a model for evaluation based on socio-technical systems theory addressing a stated need in the literature…

Relationship between Affective Learning, Instructor Attractiveness and Instructor Evaluation in Videoconference-Based Distance Education Courses

ERIC Educational Resources Information Center

Aydin, Irem E.

2012-01-01

This paper is intended to reveal the results of a study in which the relationship between learners' perceptions of affective learning, instructors' attractiveness and instructor evaluations in a videoconference based distance education course was investigated. An online survey instrument was used to collect quantitative data. A series of Pearson…

Whatever Happened to the Silent Scientific Revolution?--Research, Theory and Practice in Distance Education.

ERIC Educational Resources Information Center

Morgan, Alistair

The point of departure for this article is the title of a book edited by David Fetterman, "Qualitative Approaches to Educational Evaluation--The Silent Scientific Revolution." This article addresses the question of how the shift to a qualitative, phenomenological approach has impinged on research and evaluation in distance education.…

Testing a model of componential processing of multi-symbol numbers-evidence from measurement units.

PubMed

Huber, Stefan; Bahnmueller, Julia; Klein, Elise; Moeller, Korbinian

2015-10-01

Research on numerical cognition has addressed the processing of nonsymbolic quantities and symbolic digits extensively. However, magnitude processing of measurement units is still a neglected topic in numerical cognition research. Hence, we investigated the processing of measurement units to evaluate whether typical effects of multi-digit number processing such as the compatibility effect, the string length congruity effect, and the distance effect are also present for measurement units. In three experiments, participants had to single out the larger one of two physical quantities (e.g., lengths). In Experiment 1, the compatibility of number and measurement unit (compatible: 3 mm_6 cm with 3 < 6 and mm < cm; incompatible: 3 cm_6 mm with 3 < 6 but cm > mm) as well as string length congruity (congruent: 1 m_2 km with m < km and 2 < 3 characters; incongruent: 2 mm_1 m with mm < m, but 3 > 2 characters) were manipulated. We observed reliable compatibility effects with prolonged reaction times (RT) for incompatible trials. Moreover, a string length congruity effect was present in RT with longer RT for incongruent trials. Experiments 2 and 3 served as control experiments showing that compatibility effects persist when controlling for holistic distance and that a distance effect for measurement units exists. Our findings indicate that numbers and measurement units are processed in a componential manner and thus highlight that processing characteristics of multi-digit numbers generalize to measurement units. Thereby, our data lend further support to the recently proposed generalized model of componential multi-symbol number processing.

Effects of prolonged strenuous endurance exercise on plasma myosin heavy chain fragments and other muscular proteins. Cycling vs running.

PubMed

Koller, A; Mair, J; Schobersberger, W; Wohlfarter, T; Haid, C; Mayr, M; Villiger, B; Frey, W; Puschendorf, B

1998-03-01

This study evaluates creatine kinase, myosin heavy chain, and cardiac troponin blood levels following three types of exercise: 1) short-distance uphill or downhill running; 2) alpine ultramarathon; and 3) alpine long-distance cycling. Comparative field study; follow-up up to 10 days. Department of Sports Medicine. All biochemical markers were analysed at the Department of Medical Chemistry and Biochemistry. Subjects included healthy, trained males (N = 53). All subjects were nonsmokers and free from medication prior to and during the study. Each volunteer was an experienced runner or cyclist, who had at least once successfully finished the Swiss Alpine Marathon of Davos or the Otztal-Radmarathon before. Running or cycling. Plasma concentrations of creatine kinase, myosin heavy chain fragments and cardiac troponins were measured to diagnose skeletal and cardiac muscle damage, respectively. Skeletal muscle protein release is markedly different between uphill and downhill running, with very little evidence for muscle damage in the uphill runners. There is considerable muscle protein leakage in the ultramarathoners (67 km distance; 30 km downhill running). In contrast, only modest amounts of skeletal muscle damage are found after alpine long-distance cycling (230 km distance). This study proves that there is slow-twitch skeletal muscle fiber damage after prolonged strenuous endurance exercise and short-distance downhill running. Exhaustive endurance exercise involving downhill running and short-distance downhill running lead to more pronounced injury than strenuous endurance exercise involving concentric actions. From our results there is no reason for suggesting that prolonged intense exercise may induce myocardial injury in symptom-less athletes without cardiac deseases.

Distance Learning Students' Need: Evaluating Interactions from Moore's Theory of Transactional Distance

ERIC Educational Resources Information Center

Ustati, Rusmanizah; Hassan, Sharifah Sariah Syed

2013-01-01

This study draws on the experience from a focus group interviews under the distance learning programme known as "Program Pensiswazahan Guru" (PPG) organized by the Malaysian Ministry of Education in collaboration with local universities and institutes of education. Its purpose is to uncover students' perception about the platform used by…

Levels of Interaction Provided by Online Distance Education Models

ERIC Educational Resources Information Center

Alhih, Mohammed; Ossiannilsson, Ebba; Berigel, Muhammet

2017-01-01

Interaction plays a significant role to foster usability and quality in online education. It is one of the quality standard to reveal the evidence of practice in online distance education models. This research study aims to evaluate levels of interaction in the practices of distance education centres. It is aimed to provide online distance…

Distance Learning 2000: Proceedings of the Annual Conference on Distance Teaching & Learning (16th, Madison, Wisconsin, August 2-4, 2000).

ERIC Educational Resources Information Center

Wisconsin Univ. System, Madison.

These proceedings contain 75 papers from information sessions that address important human factors in distance education from several perspectives, including implementation planning, management and policy, instructional design, teaching methods, faculty development, learning environments, learner supports, and evaluation. Among the papers are:…

Characteristics and Activities of Teachers on Distance Learning Programs That Affect Their Ratings

ERIC Educational Resources Information Center

Stanišic Stojic, Svetlana M.; Dobrijevic, Gordana; Stanišic, Nemanja; Stanic, Nenad

2014-01-01

This paper presents an analysis of teachers' ratings on distance learning undergraduate study programs: 7,156 students enrolled in traditional and 528 students enrolled in distance learning studies took part in the evaluation questionnaire, assessing 71 teachers. The data were collected from the Moodle platform and from the Singidunum University…

The Concentric Support Model: A Model for the Planning and Evaluation of Distance Learning Programs

ERIC Educational Resources Information Center

Osika, Elizabeth

2006-01-01

Each year, the number of institutions offering distance learning courses continues to grow significantly (Green, 2002; National Center for Educational Statistics, 2003; Wagner, 2000). Broskoske and Harvey (2000) explained that "many institutions begin a distance education initiative encouraged by the potential benefits, influenced by their…

Phase Noise Influence in Long-range Coherent Optical OFDM Systems with Delay Detection, IFFT Multiplexing and FFT Demodulation

NASA Astrophysics Data System (ADS)

Jacobsen, Gunnar; Xu, Tianhua; Popov, Sergei; Sergeyev, Sergey; Zhang, Yimo

2012-12-01

We present a study of the influence of dispersion induced phase noise for CO-OFDM systems using FFT multiplexing/IFFT demultiplexing techniques (software based). The software based system provides a method for a rigorous evaluation of the phase noise variance caused by Common Phase Error (CPE) and Inter-Carrier Interference (ICI) including - for the first time to our knowledge - in explicit form the effect of equalization enhanced phase noise (EEPN). This, in turns, leads to an analytic BER specification. Numerical results focus on a CO-OFDM system with 10-25 GS/s QPSK channel modulation. A worst case constellation configuration is identified for the phase noise influence and the resulting BER is compared to the BER of a conventional single channel QPSK system with the same capacity as the CO-OFDM implementation. Results are evaluated as a function of transmission distance. For both types of systems, the phase noise variance increases significantly with increasing transmission distance. For a total capacity of 400 (1000) Gbit/s, the transmission distance to have the BER < 10-2 for the worst case CO-OFDM design is less than 800 and 460 km, respectively, whereas for a single channel QPSK system it is less than 1400 and 560 km.

Teaching, Testing, and Evaluating Roger D. Mc Leod's Models for Vision, and its Repair, by Patent-pending Naturoptics.

NASA Astrophysics Data System (ADS)

Niemi, Paul R.; D., O.; Mc Leod, David M.; Mc Leod, Roger D.

2007-04-01

RDM taught a health professional how to recover her previously impaired near vision in one session, also bringing a similar male from 20/30 to 20/10, distance vision, in about ten minutes; another health professional's improvement went from 20/300 to 20/20 in three sessions. A former athlete achieved a distance improvement from 20/800 to 20/100, again, in three sessions. RDM offers to replicate these types of improvements, using patent-pending Naturoptics under monitored conditions, and non-disclosure restraints, to protect franchising and patent-pending rights. Evening atropine use, controlled, at Singapore's National Eye Center, demonstrated an effect against myopia. Does this actually constitute an experimental verification of Mc Leod's Airy-disk radius-formula explanation of how vision works, and predicts how it can be damaged/repaired? Evaluation and documentation is to be by close and distance vision standard charts, or their equivalents, with guaranteed ``chart'' improvements of one line per session, after the beginning visit, or the session is free. Patent-pending Naturoptics differs from all vision-boosting competitors by safely re-eliciting vision's feedback control self-repairs, including astigmatism and presbyopia. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.4

CT-Guided Interventions Using a Free-Hand, Optical Tracking System: Initial Clinical Experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schubert, Tilman, E-mail: TSchubert@uhbs.ch; Jacob, Augustinus L.; Pansini, Michele

2013-08-01

PurposeThe present study was designed to evaluate the geometrical accuracy and clinical applicability of a new, free-hand, CT-guided, optical navigation system.MethodsFifteen procedures in 14 consecutive patients were retrospectively analyzed. The navigation system was applied for interventional procedures on small target lesions, in cases with long needle paths, narrow access windows, or when an out-of-plane access was expected. Mean lesion volume was 27.9 ml, and mean distance to target measured was 107.5 mm. Eleven of 15 needle trajectories were planned as out-of-plane approaches regarding the axial CT plane.ResultsNinety-one percent of the biopsies were diagnostic. All therapeutic interventions were technically successful. Targetingmore » precision was high with a mean distance of the needle tip from planned target of 1.98 mm. Mean intervention time was 1:12 h. A statistically significant correlation between angular needle deviation and intervention time (p = 0.007), respiratory movement of the target (p = 0.008), and body mass index (p = 0.02) was detected. None of the evaluated parameters correlated significantly with the distance from the needle tip to the planned target.ConclusionsThe application of a navigation system for complex CT-guided procedures provided safe and effective targeting within a reasonable intervention time in our series.« less

Power and sample-size estimation for microbiome studies using pairwise distances and PERMANOVA.

PubMed

Kelly, Brendan J; Gross, Robert; Bittinger, Kyle; Sherrill-Mix, Scott; Lewis, James D; Collman, Ronald G; Bushman, Frederic D; Li, Hongzhe

2015-08-01

The variation in community composition between microbiome samples, termed beta diversity, can be measured by pairwise distance based on either presence-absence or quantitative species abundance data. PERMANOVA, a permutation-based extension of multivariate analysis of variance to a matrix of pairwise distances, partitions within-group and between-group distances to permit assessment of the effect of an exposure or intervention (grouping factor) upon the sampled microbiome. Within-group distance and exposure/intervention effect size must be accurately modeled to estimate statistical power for a microbiome study that will be analyzed with pairwise distances and PERMANOVA. We present a framework for PERMANOVA power estimation tailored to marker-gene microbiome studies that will be analyzed by pairwise distances, which includes: (i) a novel method for distance matrix simulation that permits modeling of within-group pairwise distances according to pre-specified population parameters; (ii) a method to incorporate effects of different sizes within the simulated distance matrix; (iii) a simulation-based method for estimating PERMANOVA power from simulated distance matrices; and (iv) an R statistical software package that implements the above. Matrices of pairwise distances can be efficiently simulated to satisfy the triangle inequality and incorporate group-level effects, which are quantified by the adjusted coefficient of determination, omega-squared (ω2). From simulated distance matrices, available PERMANOVA power or necessary sample size can be estimated for a planned microbiome study. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Evaluation of Contrail Reduction Strategies Based on Aircraft Flight Distances

NASA Technical Reports Server (NTRS)

Chen, Neil Y.; Sridhar, Banavar; Li, Jinhua; Ng, Hok Kwan

2012-01-01

This paper evaluates a set of contrail reduction strategies based on the flight range of aircraft as contrail reduction strategies have different impacts on aircraft depending on how they plan to fly. In general, aircraft with longer flight distances cruise at the altitudes where contrails are more likely to form. The concept of the contrail frequency index is used to quantify contrail impacts. The strategy for reducing the persistent contrail formation is to minimize the contrail frequency index by altering the aircraft's cruising altitude. A user-defined factor is used to trade off between contrail reduction and extra CO2 emissions. A higher value of tradeoff factor results in more contrail reduction and extra CO2 emissions. Results show that contrail reduction strategies using various tradeo factors behave differently from short-range flights to long-range ights. Analysis shows that short-distance flights (less than 500 miles) are the most frequent flights but contribute least to contrail reduction. Therefore these aircraft have the lowest priority when applying contrail reduction strategies. Medium-distance flights (500 to 1000 miles) have a higher priority if the goal is to achieve maximum contrail reduction in total; long-distance flights (1000 to 1500 miles) have a higher priority if the goal is to achieve maximum contrail reduction per flight. The characteristics of transcontinental flights (greater than 1500 miles) vary with different weather days so the priority of applying contrail reduction strategies to the group needs to be evaluated based on the locations of the contrail areas during any given day. For the days tested, medium-distance ights contribute up to 42.6% of the reduction among the groups during a day. The contrail frequency index per 1,000 miles for medium-distance, long-distance, and transcontinental flights can be reduced by an average of 75%. The results provide a starting point for developing operational policies to reduce the impact of aviation on climate based on aircraft flight distances.

Effects of target distance on select biomechanical parameters in taekwondo roundhouse kick.

PubMed

Falco, Coral; Molina-García, Javier; Alvarez, Octavio; Estevan, Isaac

2013-11-01

The aim of this study was to investigate the effects of target distance on temporal and impact force parameters that are important performance factors in taekwondo kicks. Forty-nine taekwondo athletes (age = 24.5 +/- 5.9 years; mass = 79.9 +/- 10.8 kg) were recruited: 13 male experts, 21 male novices, 8 female experts, and 6 female novices. Impact force, reaction time, and execution time were computed. Three-way repeated measure ANOVAs revealed significant 'distance' effect on impact force, reaction time, and execution time (p = 0.001). Comparisons between distance conditions revealed that taekwondo athletes kicked with higher impact force from short distance (17.6 +/- 7.5 N/kg) than from long distance (13.1 +/- 5.7 N/kg) (p < 0.001), had lower reaction time from short distance (498 +/- 90 ms) and normal distance (521 +/- 111 ms) than from long distance (602 +/- 121 ms) (p < 0.001), and had lower execution time from short distance (261 +/- 69 ms/m) than from normal distance (306 +/- 105 ms/m) or from long distance (350 +/- 106 ms/m) (p = 0.003 and p < 0.001, respectively). In conclusion, target distance affected the kick performance; as distance increases, impact force decreased and reaction time increased. Therefore, when reaction to a simple visual stimulus is needed, kicking from a long distance is not recommended, as longer time is required to respond.

Radiological and micro-computed tomography analysis of the bone at dental implants inserted 2, 3 and 4 mm apart in a minipig model with platform switching incorporated.

PubMed

Elian, Nicolas; Bloom, Mitchell; Dard, Michel; Cho, Sang-Choon; Trushkowsky, Richard D; Tarnow, Dennis

2014-02-01

The purpose of this study was to assess the effect of inter-implant distance on interproximal bone utilizing platform switching. Analysis of interproximal bone usually depends on traditional two-dimensional radiographic assessment. Although there has been increased reliability of current techniques, there has been an inability to track bone level changes over time and in three dimensions. Micro-CT has provided three-dimensional imaging that can be used in conjunction with traditional two-dimensional radiographic techniques. This study was performed on 24 female minipigs. Twelve animals received three implants with an inter-implant distance of 3 mm on one side of the mandible and another three implants on the contra-lateral side, where the implants were placed 2 mm apart creating a split mouth design. Twelve other animals received three implants with an inter-implant distance of 3 mm on one side of the mandible and another three implants on the contra-lateral side, where the implants were placed 4 mm apart creating a split mouth design too. The quantitative evaluation was performed comparatively on radiographs taken at t 0 (immediately after implantation) and at t 8 weeks (after termination). The samples were scanned by micro-computed tomography (μCT) to quantify the first bone to implant contact (fBIC) and bone volume/total volume (BV/TV). Mixed model regressions using the nonparametric Brunner-Langer method were used to determine the effect of inter-implant distance on the measured outcomes. The change in bone level was determined using radiography and its mean was 0.05 mm for an inter-implant distance of 3 and 0.00 mm for a 2 mm distance (P = 0.7268). The mean of this outcome was 0.18 mm for the 3 mm and for 4 mm inter-implant distance (P = 0.9500). Micro-computed tomography showed that the fBIC was always located above the reference, 0.27 and 0.20 mm for the comparison of 2-3 mm (P = 0.4622) and 0.49 and 0.34 mm for the inter-implant distance of 3 and 4 mm (P = 0.1699). BV/TV inside the defined parallelepipedic masks reached 82.38% for the 2 mm inter-implant distance and 85.00% for 3 mm, P = 0.8432. For the comparison of the 3-4 mm inter-implant distance, the means were 84.69% and 84.38%, respectively, P = 0.8401. Non-inferiority tests for the smaller inter-implant distances for both comparisons showed similar differences and similar tolerance ranges. The effect of a smaller interproximal distances between implants on bone level, fBIC and BV/TV assessed by two convergent investigation methods, radiology and μCT, was similar to that of larger distances. Implants can potentially be placed 2 mm apart instead of 3 mm and 3 mm apart instead of 4 mm when platform switching is utilized. Further research with a conventional platform is warranted. © 2012 John Wiley & Sons A/S.

Effects of Caffeine Supplementation on Performance in Ball Games.

PubMed

Chia, Jingyi Shannon; Barrett, Laura Ann; Chow, Jia Yi; Burns, Stephen Francis

2017-12-01

Although a large body of evidence exists documenting the ergogenic properties of caffeine, most studies have focused on endurance performance. However, findings from endurance sports cannot be generalized to performance in ball games where, apart from having a high level of endurance, successful athletic performances require a combination of physiological, technical and cognitive capabilities. The purpose of this review was to critically evaluate studies that have examined the effect of a single dose of caffeine in isolation on one or more of the following performance measures: total distance, sprint performance, agility, vertical jump performance and accuracy in ball games. Searches of three major databases resulted in 19 studies (invasion games: 13; net-barrier games: 6) that evaluated the acute effects of caffeine on human participants, provided the caffeine dose administered, and included a ball games specific task or simulated match. Improvements in sprint performance were observed in 8 of 10 studies (80%), and vertical jump in 7 of 8 studies (88%). Equivocal results were reported for distance covered, agility and accuracy. Minor side effects were reported in 4 of 19 studies reviewed. Pre-exercise caffeine ingestion between 3.0 and 6.0 mg/kg of body mass appears to be a safe ergogenic aid for athletes in ball games. However, the efficacy of caffeine varies depending on various factors, including, but not limited to, the nature of the game, physical status and caffeine habituation. More research is warranted to clarify the effects of caffeine on performance measures unique to ball games, such as agility and accuracy. It is essential that athletes, coaches and practitioners evaluate the risk-benefit ratio of caffeine ingestion strategies on an individual case-by-case basis.

Evaluation of Effective Factors on Travel Time in Optimization of Bus Stops Placement Using Genetic Algorithm

NASA Astrophysics Data System (ADS)

Bargegol, Iraj; Ghorbanzadeh, Mahyar; Ghasedi, Meisam; Rastbod, Mohammad

2017-10-01

In congested cities, locating and proper designing of bus stops according to the unequal distribution of passengers is crucial issue economically and functionally, since this subject plays an important role in the use of bus system by passengers. Location of bus stops is a complicated subject; by reducing distances between stops, walking time decreases, but the total travel time may increase. In this paper, a specified corridor in the city of Rasht in north of Iran is studied. Firstly, a new formula is presented to calculate the travel time, by which the number of stops and consequently, the travel time can be optimized. An intended corridor with specified number of stops and distances between them is addressed, the related formulas to travel time are created, and its travel time is calculated. Then the corridor is modelled using a meta-heuristic method in order that the placement and the optimal distances of bus stops for that are determined. It was found that alighting and boarding time along with bus capacity are the most effective factors affecting travel time. Consequently, it is better to have more concentration on indicated factors for improving the efficiency of bus system.

Using Relative Position and Temporal Judgments to Assess the Effects of Texture and Field of View on Spatial Awareness for Synthetic Vision Systems Displays

NASA Technical Reports Server (NTRS)

Bolton, Matthew L.; Bass, Ellen J.; Comstock, James R., Jr.

2006-01-01

Synthetic Vision Systems (SVS) depict computer generated views of terrain surrounding an aircraft. In the assessment of textures and field of view (FOV) for SVS, no studies have directly measured the 3 levels of spatial awareness: identification of terrain, its relative spatial location, and its relative temporal location. This work introduced spatial awareness measures and used them to evaluate texture and FOV in SVS displays. Eighteen pilots made 4 judgments (relative angle, distance, height, and abeam time) regarding the location of terrain points displayed in 112 5-second, non-interactive simulations of a SVS heads down display. Texture produced significant main effects and trends for the magnitude of error in the relative distance, angle, and abeam time judgments. FOV was significant for the directional magnitude of error in the relative distance, angle, and height judgments. Pilots also provided subjective terrain awareness ratings that were compared with the judgment based measures. The study found that elevation fishnet, photo fishnet, and photo elevation fishnet textures best supported spatial awareness for both the judgments and the subjective awareness measures.

Fuelling decisions in migratory birds: geomagnetic cues override the seasonal effect.

PubMed

Kullberg, Cecilia; Henshaw, Ian; Jakobsson, Sven; Johansson, Patrik; Fransson, Thord

2007-09-07

Recent evaluations of both temporal and spatial precision in bird migration have called for external cues in addition to the inherited programme defining the migratory journey in terms of direction, distance and fuelling behaviour along the route. We used juvenile European robins (Erithacus rubecula) to study whether geomagnetic cues affect fuel deposition in a medium-distance migrant by simulating a migratory journey from southeast Sweden to the wintering area in southern Spain. In the late phase of the onset of autumn migration, robins exposed to the magnetic treatment attained a lower fuel load than control birds exposed to the ambient magnetic field of southeast Sweden. In contrast, robins captured in the early phase of the onset of autumn migration all showed low fuel deposition irrespective of experimental treatment. These results are, as expected, the inverse of what we have found in similar studies in a long-distance migrant, the thrush nightingale (Luscinia luscinia), indicating that the reaction in terms of fuelling behaviour to a simulated southward migration varies depending on the relevance for the species. Furthermore, we suggest that information from the geomagnetic field act as an important external cue overriding the seasonal effect on fuelling behaviour in migratory birds.

Hierarchical traits distances explain grassland Fabaceae species' ecological niches distances.

PubMed

Fort, Florian; Jouany, Claire; Cruz, Pablo

2015-01-01

Fabaceae species play a key role in ecosystem functioning through their capacity to fix atmospheric nitrogen via their symbiosis with Rhizobium bacteria. To increase benefits of using Fabaceae in agricultural systems, it is necessary to find ways to evaluate species or genotypes having potential adaptations to sub-optimal growth conditions. We evaluated the relevance of phylogenetic distance, absolute trait distance and hierarchical trait distance for comparing the adaptation of 13 grassland Fabaceae species to different habitats, i.e., ecological niches. We measured a wide range of functional traits (root traits, leaf traits, and whole plant traits) in these species. Species phylogenetic and ecological distances were assessed from a species-level phylogenetic tree and species' ecological indicator values, respectively. We demonstrated that differences in ecological niches between grassland Fabaceae species were related more to their hierarchical trait distances than to their phylogenetic distances. We showed that grassland Fabaceae functional traits tend to converge among species with the same ecological requirements. Species with acquisitive root strategies (thin roots, shallow root systems) are competitive species adapted to non-stressful meadows, while conservative ones (coarse roots, deep root systems) are able to tolerate stressful continental climates. In contrast, acquisitive species appeared to be able to tolerate low soil-P availability, while conservative ones need high P availability. Finally we highlight that traits converge along the ecological gradient, providing the assumption that species with similar root-trait values are better able to coexist, regardless of their phylogenetic distance.

Hierarchical traits distances explain grassland Fabaceae species' ecological niches distances

PubMed Central

Fort, Florian; Jouany, Claire; Cruz, Pablo

2015-01-01

Fabaceae species play a key role in ecosystem functioning through their capacity to fix atmospheric nitrogen via their symbiosis with Rhizobium bacteria. To increase benefits of using Fabaceae in agricultural systems, it is necessary to find ways to evaluate species or genotypes having potential adaptations to sub-optimal growth conditions. We evaluated the relevance of phylogenetic distance, absolute trait distance and hierarchical trait distance for comparing the adaptation of 13 grassland Fabaceae species to different habitats, i.e., ecological niches. We measured a wide range of functional traits (root traits, leaf traits, and whole plant traits) in these species. Species phylogenetic and ecological distances were assessed from a species-level phylogenetic tree and species' ecological indicator values, respectively. We demonstrated that differences in ecological niches between grassland Fabaceae species were related more to their hierarchical trait distances than to their phylogenetic distances. We showed that grassland Fabaceae functional traits tend to converge among species with the same ecological requirements. Species with acquisitive root strategies (thin roots, shallow root systems) are competitive species adapted to non-stressful meadows, while conservative ones (coarse roots, deep root systems) are able to tolerate stressful continental climates. In contrast, acquisitive species appeared to be able to tolerate low soil-P availability, while conservative ones need high P availability. Finally we highlight that traits converge along the ecological gradient, providing the assumption that species with similar root-trait values are better able to coexist, regardless of their phylogenetic distance. PMID:25741353

Relativistic effects in the energy loss of a fast charged particle moving parallel to a two-dimensional electron gas

NASA Astrophysics Data System (ADS)

Mišković, Zoran L.; Akbari, Kamran; Segui, Silvina; Gervasoni, Juana L.; Arista, Néstor R.

2018-05-01

We present a fully relativistic formulation for the energy loss rate of a charged particle moving parallel to a sheet containing two-dimensional electron gas, allowing that its in-plane polarization may be described by different longitudinal and transverse conductivities. We apply our formulation to the case of a doped graphene layer in the terahertz range of frequencies, where excitation of the Dirac plasmon polariton (DPP) in graphene plays a major role. By using the Drude model with zero damping we evaluate the energy loss rate due to excitation of the DPP, and show that the retardation effects are important when the incident particle speed and its distance from graphene both increase. Interestingly, the retarded energy loss rate obtained in this manner may be both larger and smaller than its non-retarded counterpart for different combinations of the particle speed and distance.

Comparative treatment effectiveness of conventional trench and seepage pit systems.

PubMed

Field, J P; Farrell-Poe, K L; Walworth, J L

2007-03-01

On-site wastewater treatment systems can be a potential source of groundwater contamination in regions throughout the United States and other parts of the world. Here, we evaluate four conventional trench systems and four seepage pit systems to determine the relative effectiveness of these systems for the treatment of septic tank effluent in medium- to coarse-textured arid and semiarid soils. Soil borings were advanced up to twice the depth of the trenches (4 m) and seepage pits (15 m) at two horizontal distances (30 cm and 1.5 m) from the sidewalls of the systems. Soil samples were analyzed for various biological and chemical parameters, including Escherichia coli, total coliform, pH, total organic carbon, total dissolved solids, total nitrogen, ammonium-nitrogen, and nitrate-nitrogen. Most soil parameters investigated approached background levels more rapidly near the trenches than the seepage pits, as sampling distance increased both vertically and horizontally from the sidewalls of the systems.

Bayesian comparison of protein structures using partial Procrustes distance.

PubMed

Ejlali, Nasim; Faghihi, Mohammad Reza; Sadeghi, Mehdi

2017-09-26

An important topic in bioinformatics is the protein structure alignment. Some statistical methods have been proposed for this problem, but most of them align two protein structures based on the global geometric information without considering the effect of neighbourhood in the structures. In this paper, we provide a Bayesian model to align protein structures, by considering the effect of both local and global geometric information of protein structures. Local geometric information is incorporated to the model through the partial Procrustes distance of small substructures. These substructures are composed of β-carbon atoms from the side chains. Parameters are estimated using a Markov chain Monte Carlo (MCMC) approach. We evaluate the performance of our model through some simulation studies. Furthermore, we apply our model to a real dataset and assess the accuracy and convergence rate. Results show that our model is much more efficient than previous approaches.

Safe separation distance score: A new metric for evaluating wildland firefighter safety zones using lidar

Treesearch

Michael J. Campbell; Philip E. Dennison; Bret W. Butler

2016-01-01

Safety zones are areas where firefighters can retreat to in order to avoid bodily harm when threatened by burnover or entrapment from wildland fire. At present, safety zones are primarily designated by firefighting personnel as part of daily fire management activities. Though critical to safety zone assessment, the effectiveness of this approach is inherently limited...

Interactive Televised Social Work Practice Courses: an Evaluation of On-Site and Remote-Site Students' Educational Outcomes and Satisfaction

ERIC Educational Resources Information Center

Rehder, Kylene

2013-01-01

Social work is a growing profession and its education is expanding through the use of technology supported learning environments. Although distance education opportunities are increasing, social work educators and administrators continue to question its suitability. Much of the skepticism is rooted in the belief that to effectively educate about…

Time and distance to clear wood in pruned red alder saplings.

Treesearch

Dean S. DeBell; Constance A. Harrington; Barbara L. Gartner; Ryan. Singleton

2006-01-01

Pruning trials in young alder stands were sampled to evaluate response to pruning. Effects of pruning (1) live branches on different dates, and (2) dead branches with or without damaging the branch collar were assessed on trees pruned in 3- and 6-year-old plantations, respectively. Six years after pruning, stem sections were collected and dissected in the longitudinal-...

CAD/CAM at a Distance: Assessing the Effectiveness of Web-Based Instruction To Meet Workforce Development Needs. AIR 2000 Annual Forum Paper.

ERIC Educational Resources Information Center

Wilkerson, Joyce A.; Elkins, Susan A.

This qualitative case study assessed web-based instruction in a computer-aided design/computer-assisted manufacturing (CAD/CAM) course designed for workforce development. The study examined students' and instructors' experience in a CAD/CAM course delivered exclusively on the Internet, evaluating course content and delivery, clarity of…

Extension Education: Training Coordinators to Facilitate Distance Education through the Assemblies of God Bible Institute in Belize

ERIC Educational Resources Information Center

Castleberry, Terry Lane

2010-01-01

The specific objective of this project was to train coordinators to open new extension classes and effectively facilitate existing extension classes offered by the Assemblies of God Bible Institute (AGBI) in Belize. Extensive biblical and literary research and a thorough evaluation of current extension classes led to the development of a…

Assessing the Battery Cost at Which Plug-In Hybrid Medium-Duty Parcel Delivery Vehicles Become Cost-Effective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramroth, L. A.; Gonder, J. D.; Brooker, A. D.

2013-04-01

The National Renewable Energy Laboratory (NREL) validated diesel-conventional and diesel-hybrid medium-duty parcel delivery vehicle models to evaluate petroleum reductions and cost implications of hybrid and plug-in hybrid diesel variants. The hybrid and plug-in hybrid variants are run on a field data-derived design matrix to analyze the effect of drive cycle, distance, engine downsizing, battery replacements, and battery energy on fuel consumption and lifetime cost. For an array of diesel fuel costs, the battery cost per kilowatt-hour at which the hybridized configuration becomes cost-effective is calculated. This builds on a previous analysis that found the fuel savings from medium duty plug-inmore » hybrids more than offset the vehicles' incremental price under future battery and fuel cost projections, but that they seldom did so under present day cost assumptions in the absence of purchase incentives. The results also highlight the importance of understanding the application's drive cycle specific daily distance and kinetic intensity.« less

Effectiveness of ultrasound-guided transversus abdominis plane block and rectus sheath block in pain control and recovery after gynecological transumbilical single-incision laparoscopic surgery.

PubMed

Mugita, M; Kawahara, R; Tamai, Y; Yamasaki, K; Okuno, S; Hanada, R; Inaoka, M; Funato, T

2014-01-01

To evaluate the effectiveness of ultrasound-guided transversus abdominis plane (TAP) and rectus sheath (RS) blocks in pain management and recovery after gynecological single-incision laparoscopic surgery (SILS). Abilateral TAP block (Group A, n = 9), bilateral TAP and RS blocks (Group B, n = 10), and a bilateral RS block (Group C, n = 9) with 40 ml ropivacaine per patient were conducted in 28 patients undergoing SILS for ovarian tumors. A pain score and walking distance in a 6-minute walk test (6MWT) were examined. Pain scores were significantly lower on postoperative day (POD) 3 than on POD 1 in Groups B (p = 0.03) and C (p = 0.02). The walking distance on POD 3 was comparable with that before surgery in Group C (p = 0.75), but shorter in Groups A (p = 0.004) and B (p = 0.02). The RS block alone was the most effective in relieving pain and accelerating general recovery after gynecological SILS.

NGA-West 2 Equations for predicting PGA, PGV, and 5%-Damped PSA for shallow crustal earthquakes

USGS Publications Warehouse

Boore, David M.; Stewart, Jon P.; Seyhan, Emel; Atkinson, Gail M.

2013-01-01

We provide ground-motion prediction equations for computing medians and standard deviations of average horizontal component intensity measures (IMs) for shallow crustal earthquakes in active tectonic regions. The equations were derived from a global database with M 3.0–7.9 events. We derived equations for the primary M- and distance-dependence of the IMs after fixing the VS30-based nonlinear site term from a parallel NGA-West 2 study. We then evaluated additional effects using mixed effects residuals analysis, which revealed no trends with source depth over the M range of interest, indistinct Class 1 and 2 event IMs, and basin depth effects that increase and decrease long-period IMs for depths larger and smaller, respectively, than means from regional VS30-depth relations. Our aleatory variability model captures decreasing between-event variability with M, as well as within-event variability that increases or decreases with M depending on period, increases with distance, and decreases for soft sites.

Going beyond Kirkpatrick's Training Evaluation Model: The Role of Workplace Factors in Distance Learning Transfer

ERIC Educational Resources Information Center

Aluko, F. R.; Shonubi, O. K.

2014-01-01

This article emanates from a longitudinal study of the impact of a distance education programme for teacher training on graduates' job performance, in which the authors built on the findings of a previous pilot study. After using Kirkpatrick's Training Evaluation Model in a previous study, one of the authors found there to be a strong relationship…

The Importance of Distance to Resources in the Spatial Modelling of Bat Foraging Habitat

PubMed Central

Rainho, Ana; Palmeirim, Jorge M.

2011-01-01

Many bats are threatened by habitat loss, but opportunities to manage their habitats are now increasing. Success of management depends greatly on the capacity to determine where and how interventions should take place, so models predicting how animals use landscapes are important to plan them. Bats are quite distinctive in the way they use space for foraging because (i) most are colonial central-place foragers and (ii) exploit scattered and distant resources, although this increases flying costs. To evaluate how important distances to resources are in modelling foraging bat habitat suitability, we radio-tracked two cave-dwelling species of conservation concern (Rhinolophus mehelyi and Miniopterus schreibersii) in a Mediterranean landscape. Habitat and distance variables were evaluated using logistic regression modelling. Distance variables greatly increased the performance of models, and distance to roost and to drinking water could alone explain 86 and 73% of the use of space by M. schreibersii and R. mehelyi, respectively. Land-cover and soil productivity also provided a significant contribution to the final models. Habitat suitability maps generated by models with and without distance variables differed substantially, confirming the shortcomings of maps generated without distance variables. Indeed, areas shown as highly suitable in maps generated without distance variables proved poorly suitable when distance variables were also considered. We concluded that distances to resources are determinant in the way bats forage across the landscape, and that using distance variables substantially improves the accuracy of suitability maps generated with spatially explicit models. Consequently, modelling with these variables is important to guide habitat management in bats and similarly mobile animals, particularly if they are central-place foragers or depend on spatially scarce resources. PMID:21547076

Are Perceived and Objective Distances to Fresh Food and Physical Activity Resources Associated with Cardiometabolic Risk?

PubMed

Baldock, Katherine L; Paquet, Catherine; Howard, Natasha J; Coffee, Neil T; Taylor, Anne W; Daniel, Mark

2018-01-29

Perceived and objective measures of neighbourhood features have shown limited correspondence. Few studies have examined whether discordance between objective measures and individual perceptions of neighbourhood environments relates to individual health. Individuals with mismatched perceptions may benefit from initiatives to improve understandings of resource availability. This study utilised data from n = 1491 adult participants in a biomedical cohort to evaluate cross-sectional associations between measures of access (perceived, objective, and perceived-objective mismatch) to fruit and vegetable retailers (FVR) and public open space (POS), and clinically-measured metabolic syndrome and its component risk factors: central obesity, dyslipidaemia, hypertension and pre-diabetes/diabetes. Access measures included perceived distances from home to the nearest FVR and POS, corresponding objectively-assessed road network distances, and the discordance between perceived and objective distances (overestimated (i.e., mismatched) distances versus matched perceived-objective distances). Individual and neighbourhood measures were spatially joined using a geographic information system. Associations were evaluated using multilevel logistic regression, accounting for individual and area-level covariates. Hypertension was positively associated with perceived distances to FVR (odds ratio (OR) = 1.14, 95% confidence interval (CI) = 1.02, 1.28) and POS (OR = 1.19, 95% CI = 1.05, 1.34), after accounting for covariates and objective distances. Hypertension was positively associated with overestimating distances to FVR (OR = 1.36, 95% CI = 1.02, 1.80). Overestimating distances to POS was positively associated with both hypertension (OR = 1.42, 95% CI = 1.11, 1.83) and dyslipidaemia (OR = 1.25, 95% CI = 1.00, 1.57). Results provide new evidence for specific associations between perceived and overestimated distances from home to nearby resources and cardiometabolic risk factors.

[Leeches, phytotherapy and physiotherapy in osteo-arthrosis of the knee--a geriatric case study].

PubMed

Teut, Michael; Warning, Albrecht

2008-10-01

Chronic pain is a serious problem for geriatric patients. Conventional pharmacotherapy with nonsteroidal anti-inflammatory drugs or opiates is often accompanied by serious side effects. An 87-year-old woman with severe joint pain due to osteoarthritis of the knee presented with side effects from fentanyl therapy. She was subsequently treated in an inpatient setting with leeches, phytotherapy, physiotherapy and three single doses of metamizol. Prospective single-case study. Pain reduction was assessed with a numeric rating scale (0-10; 0 = minimum; 10 = maximum), mobility by walking distance, and activities of daily living by Barthel index. The association between complementary therapy and the changes observed in the patient under treatment were evaluated using cognition-based medicine. Under complementary therapy, the patient experienced a clear reduction in pain (from 8 to 3 points on the numeric rating scale); regained the ability to walk (increase in walking distance from 0 to 70 m); and showed improvements in activities of daily living (increase in Barthel index from 45 to 65). An association between pain reduction and the complementary treatment setting seems likely. The role of complementary pain therapy in geriatric patients should be evaluated systematically. 2008 S. Karger AG, Basel

Evaluation of Distance Education Components of e-MBA Program--A Case Study

ERIC Educational Resources Information Center

Gunes, Ali; Altintas, Tugba

2013-01-01

By 2008-2009 educational year, distance education e-MBA Program have been added to Graduate School of Social Sciences of Istanbul Aydin University. The distance education components that were used included asynchronous education, synchronous education, exams, the learning management system-web site and a remote live-support desk. At the end of the…

Cross-Sectional Evaluation of Distance Education Students' Learning Styles and Critical Thinking Dispositions in Turkey

ERIC Educational Resources Information Center

Yüksel, Ismail; Türkses, Ercüment

2015-01-01

This study aims to examine distance education students' learning styles and critical thinking dispositions. This cross sectional survey was conducted on 114 Turkish distance education students from various departments in a state university. The data of the study were collected through Grasha-Riechmann Student Learning Style Scale (GRSLSS) and…

Building Academic Quality in Distance Higher Education. A Monograph in Higher Education Evaluation and Policy.

ERIC Educational Resources Information Center

Chacon-Duque, Fabio J.

The factors that determine course completion and achievement in college distance education were investigated using a sample of 25 courses offered through the Independent Learning Program at the Pennsylvania State University. The main objective was to develop a multivariate model to explain and predict outcomes of distance education. Additional…

Using goal setting and feedback to increase weekly running distance.

PubMed

Wack, Stephanie R; Crosland, Kimberly A; Miltenberger, Raymond G

2014-01-01

We evaluated goal setting with performance feedback to increase running distance among 5 healthy adults. Participants set a short-term goal each week and a long-term goal to achieve on completion of the study. Results demonstrated that goal setting and performance feedback increased running distance for all participants. © Society for the Experimental Analysis of Behavior.

Video in Distance Education: ITFS vs. Web-Streaming--Evaluation of Student Attitudes

ERIC Educational Resources Information Center

Reisslein, Jana; Seeling, Patrick; Reisslein, Martin

2005-01-01

The use of video in distance education courses has a long tradition, with many colleges and universities having been delivering distance education courses with video since the 80's using the Instructional Television Fixed Service (ITFS) and cable television. With the emergence of the Internet and the increased access bandwidths from private homes…

Student outcomes of distance learning in nursing education: an integrative review.

PubMed

Patterson, Barbara J; Krouse, Anne M; Roy, Linda

2012-09-01

Distance learning offers a distinctive environment to educate nursing students. While there is a significant body of evidence in the literature related to course, program, and faculty outcomes of distance education, little attention has been given by researchers to evaluate student outcomes, with the exception of student satisfaction. There is a need to evaluate and translate findings related to student outcomes in distance learning into educational practice. Integrative reviews offer one strategy to contribute to evidence-based teaching practice initiatives. A search of available published qualitative and quantitative research on student outcomes of distance learning from 1999 to 2009 was conducted using a number of databases. Astin's Input-Environment-Output conceptual model provided a framework for this review. Thirty-three studies met the inclusion criteria. Bothcognitive and affective student outcomes emerged. The cognitive outcomes were student learning, learning process, and technology proficiency. Affective outcomes included personal and professional growth, satisfaction, and connectedness. Implications, recommendations, and future research are discussed.

Duration, distance, and speed judgments of two moving objects by 4- to 11-year olds.

PubMed

Matsuda, F

1996-11-01

Four- to 11-year-old children (N = 133) made duration, distance, and speed judgments on a Piagetian task where two cars ran on two parallel tracks. Special effort was made to make duration judgment tasks and distance judgment tasks comparable. Among younger children, difficulties of duration judgments and distance judgments were approximately the same. Additionally, temporal attributes had nearly the same effects on duration judgments as spatial attributes had on distance judgments, and spatial attributes had nearly the same effects on duration judgments as temporal attributes had on distance judgments. Among older children, distance judgments were easier than duration judgments, and the above-mentioned symmetry in effects of temporal and spatial attributes decreased somewhat. Temporal and spatial attributes affected speed judgments equally, across age groups.

The effect of balneotherapy on patients with ankylosing spondylitis.

PubMed

Altan, L; Bingöl, U; Aslan, M; Yurtkuran, M

2006-01-01

To compare the effect of balneotherapy on physical activity and quality of life as well as the symptoms of pain and stiffness with exercise alone in ankylosing spondylitis (AS) patients. A total of 60 patients who had a diagnosis of AS according to the modified New York criteria were included in the study. The patients were randomly assigned to two groups. In Group I (n = 30) the patients received balneotherapy in a therapeutic pool for 30 min once a day for 3 weeks. All patients received instructions on the exercise programme, which they were requested to repeat once a day for 30 min during the study. The patients in this group continued the same exercise programme after the end of the balneotherapy protocol to complete a course of 6 months. In Group II the patients were given the same exercise protocol but did not receive balneotherapy. Patients were evaluated before the start of the study and at 3 weeks and 24 weeks. Evaluation parameters were daily and night pain, morning stiffness, the patient's global evaluation and the physician's global evaluation (according to a scoring system of 1 to 5), the Bath Ankylosing Spondilitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Dougados Functional Index (DFI), tragus-wall distance, chest expansion, modified Shober test (MST), fingertip-fibula head distance, and Nottingham Health Profile (NHP). Evaluations were completed in 54 patients in the two groups. Comparison of the groups showed significantly superior results for Group I for parameters of BASDAI, NHP total, pain, physical activity, tiredness and sleep score, patient's global evaluation and the physician's global evaluation at 3 weeks, but only for the parameters of patient's global evaluation and MST at 24 weeks. Balneotherapy has a supplementary effect on improvement in disease activity and functional parameters in AS patients immediately after the treatment period. However, in the light of our medium-term evaluation results, we suggest that further research is needed to assess the role of balneotherapy applied for longer durations in AS patients.

Quantification of lung perfusion blood volume (lung PBV) by dual-energy CT in patients with chronic thromboembolic pulmonary hypertension (CTEPH) before and after balloon pulmonary angioplasty (BPA): Preliminary results.

PubMed

Koike, Hirofumi; Sueyoshi, Eijun; Sakamoto, Ichiro; Uetani, Masataka; Nakata, Tomoo; Maemura, Kouji

2016-09-01

Balloon pulmonary angioplasty (BPA) is a treatment option for patients with chronic thromboembolic pulmonary hypertension (CTEPH). Its effect on pulmonary perfusion has not been quantified; we examined the clinical significance of pulmonary blood volume (PBV) using dual-energy computed tomography (DECT) in patients with CTEPH undergoing BPA. In this retrospective study of 16 BPAs in eight female patients with CTEPH, we evaluated both-lung (n=16), right- or left-lung (n=32), and three right- or left-segment (upper, middle, and lower) (n=96) PBVs before and after BPA, using DECT. We evaluated the relationships between improvement in lung PBV and pulmonary artery (PA) pressure (PAP), cardiac index (CI), pulmonary vascular resistance (PVR), and 6-min walking distance. We measured PA enhancement (PAenh) on DECT images and calculated lung PBV/PAenh to adjust timing. Pre- and post-BPA 6-segment lung PBV/PAenh were 0.067±0.021 and 0.077±0.019, respectively, in the treated segment (p<0.0001). There were significant positive correlations between pre- to post-BPA improvements in both-lung PBV/PAenh and PAP (R=0.69, p=0.005), PVR (R=0.56, p=0.03), and 6-min walking distance (R=0.67, p=0.01). Improved PBV after BPA, reflecting increased lung perfusion, was positively correlated with PAP, PVR, and 6-min walking distance. Lung PBV may be an indicator of BPA treatment effect. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Multiple factors affect a population of Agassiz's desert tortoise (Gopherus agassizii) in the Northwestern Mojave Desert

USGS Publications Warehouse

Berry, Kristin H.; Yee, Julie L.; Coble, Ashley A.; Perry, William M.; Shields, Timothy A.

2013-01-01

Numerous factors have contributed to declines in populations of the federally threatened Agassiz's Desert Tortoise (Gopherus agassizii) and continue to limit recovery. In 2010, we surveyed a low-density population on a military test facility in the northwestern Mojave Desert of California, USA, to evaluate population status and identify potential factors contributing to distribution and low densities. Estimated densities of live tortoises ranged spatially from 1.2/km2 to 15.1/km2. Although only one death of a breeding-age tortoise was recorded for the 4-yr period prior to the survey, remains of 16 juvenile and immature tortoises were found, and most showed signs of predation by Common Ravens (Corvus corax) and mammals. Predation may have limited recruitment of young tortoises into the adult size classes. To evaluate the relative importance of different types of impacts to tortoises, we developed predictive models for spatially explicit densities of tortoise sign and live tortoises using topography (i.e., slope), predators (Common Raven, signs of mammalian predators), and anthropogenic impacts (distances from paved road and denuded areas, density of ordnance fragments) as covariates. Models suggest that densities of tortoise sign increased with slope and signs of mammalian predators and decreased with Common Ravens, while also varying based on interaction effects involving these predictors as well as distances from paved roads, denuded areas, and ordnance. Similarly, densities of live tortoises varied by interaction effects among distances to denuded areas and paved roads, density of ordnance fragments, and slope. Thus multiple factors predict the densities and distribution of this population.

Distance learning for University Physics in South Africa

NASA Astrophysics Data System (ADS)

Cilliers, J. A.; Basson, I.

1997-03-01

The University of South Africa (Unisa) is one of the largest distance education universities in the world. Teaching physics at a distance is a complex and multifaceted problem which is compounded in the South African context by the diversity of educational backgrounds of the learners involved. The fact that students are distributed over a vast geographical area, presents unique problems for the incorporation of the practical component into the curriculum. Current research involves a fundamental evaluation of the aims and objectives of the introductory laboratory. The project is based on the notion that practicals, as they have been used in most physics curricula, are not particularly effective or efficient, although they are costly both financially and logistically. Design, development and delivery of efficient study material imply that there should be agreement between what the student knows and can do, and what the material offers. An in depth profile that takes into account biographic as well as cognitive characteristics of the target group, is therefore being compiled. This paper gives an overview of the specific problems and circumstances that were identified for distance education in physics in a multi-cultural society, and proposes a new model for the incorporation of the introductory laboratory into the curriculum.

Psychophysics of human echolocation.

PubMed

Schörnich, Sven; Wallmeier, Ludwig; Gessele, Nikodemus; Nagy, Andreas; Schranner, Michael; Kish, Daniel; Wiegrebe, Lutz

2013-01-01

The skills of some blind humans orienting in their environment through the auditory analysis of reflections from self-generated sounds have received only little scientific attention to date. Here we present data from a series of formal psychophysical experiments with sighted subjects trained to evaluate features of a virtual echo-acoustic space, allowing for rigid and fine-grain control of the stimulus parameters. The data show how subjects shape both their vocalisations and auditory analysis of the echoes to serve specific echo-acoustic tasks. First, we show that humans can echo-acoustically discriminate target distances with a resolution of less than 1 m for reference distances above 3.4 m. For a reference distance of 1.7 m, corresponding to an echo delay of only 10 ms, distance JNDs were typically around 0.5 m. Second, we explore the interplay between the precedence effect and echolocation. We show that the strong perceptual asymmetry between lead and lag is weakened during echolocation. Finally, we show that through the auditory analysis of self-generated sounds, subjects discriminate room-size changes as small as 10%.In summary, the current data confirm the practical efficacy of human echolocation, and they provide a rigid psychophysical basis for addressing its neural foundations.

Effects of weighted and un-weighted pendulum exercises on ultrasonographic acromiohumeral distance in patients with subacromial impingement syndrome.

PubMed

Akkaya, Nuray; Akkaya, Semih; Gungor, Harun R; Yaşar, Gokce; Atalay, Nilgun Simsir; Sahin, Fusun

2017-01-01

Although functional results of combined rehabilitation programs are reported, there have been no reports studying the effects of solo pendulum exercises on ultrasonographic measurements of acromiohumeral distance (AHD). To investigate the effects of weighted and un-weighted pendulum exercises on ultrasonographic AHD and clinical symptoms in patients with subacromial impingement syndrome. Patients with subacromial impingement syndrome were randomized to performing weighted (1.5 kilograms hand held dumbbell, N= 18) or un-weighted (free of weight, N= 16) pendulum exercises for 4 weeks, 3 sessions/day. Exercises were repeated for each direction of shoulder motion in each session (ten minutes). Clinical situation was evaluated by Constant score and Shoulder Pain Disability Index (SPADI). Ultrasonographic measurements of AHD at 0°, 30° and 60° shoulder abduction were performed. All clinical and ultrasonographic evaluations were performed at the beginning of the exercise program and at end of 4 weeks of exercise program. Thirty-four patients (23 females, 11 males; mean age 41.7 ± 8.9 years) were evaluated. Significant clinical improvements were detected in both exercise groups between pre and post-treatment evaluations (p < 0.05). There was no significant difference for pre and post-treatment AHD measurements at 0°, 30°, and 60° shoulder abduction between groups (p > 0.05). There was no significant difference for pre and post-treatment narrowing of AHD (narrowing of 0°-30°, and 0°-60°) between groups (p > 0.05). While significant clinical improvements were achieved with both weighted and un-weighted solo pendulum exercises, no significant difference was detected for ultrasonographic AHD measurements between exercise groups.

An Evaluation of the Impact of E-Learning Media Formats on Student Perception and Performance

NASA Astrophysics Data System (ADS)

Kurbel, Karl; Stankov, Ivo; Datsenka, Rastsislau

Factors influencing student evaluation of web-based courses are analyzed, based on student feedback from an online distance-learning graduate program. The impact of different media formats on the perception of the courses by the students as well as on their performance in these courses are examined. In particular, we studied conventional hypertext-based courses, video-based courses and audio-based courses, and tried to find out whether the media format has an effect on how students assess courses and how good or bad their grades are. Statistical analyses were performed to answer several research questions related to the topic and to properly evaluate the factors influencing student evaluation.

Cross-layer Energy Optimization Under Image Quality Constraints for Wireless Image Transmissions.

PubMed

Yang, Na; Demirkol, Ilker; Heinzelman, Wendi

2012-01-01

Wireless image transmission is critical in many applications, such as surveillance and environment monitoring. In order to make the best use of the limited energy of the battery-operated cameras, while satisfying the application-level image quality constraints, cross-layer design is critical. In this paper, we develop an image transmission model that allows the application layer (e.g., the user) to specify an image quality constraint, and optimizes the lower layer parameters of transmit power and packet length, to minimize the energy dissipation in image transmission over a given distance. The effectiveness of this approach is evaluated by applying the proposed energy optimization to a reference ZigBee system and a WiFi system, and also by comparing to an energy optimization study that does not consider any image quality constraint. Evaluations show that our scheme outperforms the default settings of the investigated commercial devices and saves a significant amount of energy at middle-to-large transmission distances.

Fracture identification based on remote detection acoustic reflection logging

NASA Astrophysics Data System (ADS)

Zhang, Gong; Li, Ning; Guo, Hong-Wei; Wu, Hong-Liang; Luo, Chao

2015-12-01

Fracture identification is important for the evaluation of carbonate reservoirs. However, conventional logging equipment has small depth of investigation and cannot detect rock fractures more than three meters away from the borehole. Remote acoustic logging uses phase-controlled array-transmitting and long sound probes that increase the depth of investigation. The interpretation of logging data with respect to fractures is typically guided by practical experience rather than theory and is often ambiguous. We use remote acoustic reflection logging data and high-order finite-difference approximations in the forward modeling and prestack reverse-time migration to image fractures. First, we perform forward modeling of the fracture responses as a function of the fracture-borehole wall distance, aperture, and dip angle. Second, we extract the energy intensity within the imaging area to determine whether the fracture can be identified as the formation velocity is varied. Finally, we evaluate the effect of the fracture-borehole distance, fracture aperture, and dip angle on fracture identification.

Promoting occupational health nursing training: an educational outreach with a blended model of distance and traditional learning approaches.

PubMed

Ward, Julie A; Beaton, Randal D; Bruck, Annie M; de Castro, A B

2011-09-01

In 2009, occupational health nursing faculty and professionals at the University of Washington developed an innovative continuing nursing education offering, the OHN Institute. The OHN Institute was designed to meet the following objectives: (1) extend basic occupational health nursing training to non-occupational health nurses in Federal Region X, (2) target new occupational health nurses or those who possessed little or no advanced education in occupational health nursing, and (3) offer a hybrid continuing nursing education program consisting of on-site and distance learning modalities. Evaluation findings suggested that the various continuing nursing education modalities and formats (e.g., asynchronous vs. synchronous, online modules vs. live modules) were essentially comparable in terms of effectiveness. Perhaps most importantly, the OHN Institute evaluation demonstrated that quality continuing nursing education outcomes for occupational health nurses depended largely on knowledgeable and engaging faculty and a compelling vision of desired outcomes, including the application of learned content to professional practice. Copyright 2011, SLACK Incorporated.

Power and sample-size estimation for microbiome studies using pairwise distances and PERMANOVA

PubMed Central

Kelly, Brendan J.; Gross, Robert; Bittinger, Kyle; Sherrill-Mix, Scott; Lewis, James D.; Collman, Ronald G.; Bushman, Frederic D.; Li, Hongzhe

2015-01-01

Motivation: The variation in community composition between microbiome samples, termed beta diversity, can be measured by pairwise distance based on either presence–absence or quantitative species abundance data. PERMANOVA, a permutation-based extension of multivariate analysis of variance to a matrix of pairwise distances, partitions within-group and between-group distances to permit assessment of the effect of an exposure or intervention (grouping factor) upon the sampled microbiome. Within-group distance and exposure/intervention effect size must be accurately modeled to estimate statistical power for a microbiome study that will be analyzed with pairwise distances and PERMANOVA. Results: We present a framework for PERMANOVA power estimation tailored to marker-gene microbiome studies that will be analyzed by pairwise distances, which includes: (i) a novel method for distance matrix simulation that permits modeling of within-group pairwise distances according to pre-specified population parameters; (ii) a method to incorporate effects of different sizes within the simulated distance matrix; (iii) a simulation-based method for estimating PERMANOVA power from simulated distance matrices; and (iv) an R statistical software package that implements the above. Matrices of pairwise distances can be efficiently simulated to satisfy the triangle inequality and incorporate group-level effects, which are quantified by the adjusted coefficient of determination, omega-squared (ω2). From simulated distance matrices, available PERMANOVA power or necessary sample size can be estimated for a planned microbiome study. Availability and implementation: http://github.com/brendankelly/micropower. Contact: brendank@mail.med.upenn.edu or hongzhe@upenn.edu PMID:25819674

Qualitation and Quantitation on Microplasma Jet for Bacteria Inactivation.

PubMed

Du, ChangMing; Liu, Ya; Huang, YaNi; Li, ZiMing; Men, Rui; Men, Yue; Tang, Jun

2016-01-06

In this work, a self-made microplasma jet system was used to conduct the qualitation and quantitation of inactivation with Escherichia coli as the target bacteria. The logarithmic concentration and the size of antimicrobial rings served as the evaluation parameters, respectively. The effect of various parameters on inactivation effect was studied. The results showed that the majority of bacteria had been inactivated in 30 s. The inactivation effect enhanced and then weakened with the increase of air flow rate, and receded as the extension of treatment distance. The effect with different carrier gases showed as follows: oxygen > air > nitrogen > argon. Meanwhile, the effect of different components of microplasma was studied in the optimum conditions (The flow rate was 5 L/min; inactivation distance was 2 cm). The results showed that electrically neutral active species was the main factor of inactivation rather than heating effect, ultraviolet radiation and charged particles. Finally the experiments of thallus change proved that microplasma jet had etching effect on cell membrane. It also found that microplasma could degrade organic material like protein. Furthermore, the images of scanning electron microscope (SEM) revealed the change of cell morphology step by step in the whole process of inactivation.

Qualitation and Quantitation on Microplasma Jet for Bacteria Inactivation

NASA Astrophysics Data System (ADS)

Du, Changming; Liu, Ya; Huang, Yani; Li, Ziming; Men, Rui; Men, Yue; Tang, Jun

2016-01-01

In this work, a self-made microplasma jet system was used to conduct the qualitation and quantitation of inactivation with Escherichia coli as the target bacteria. The logarithmic concentration and the size of antimicrobial rings served as the evaluation parameters, respectively. The effect of various parameters on inactivation effect was studied. The results showed that the majority of bacteria had been inactivated in 30 s. The inactivation effect enhanced and then weakened with the increase of air flow rate, and receded as the extension of treatment distance. The effect with different carrier gases showed as follows: oxygen > air > nitrogen > argon. Meanwhile, the effect of different components of microplasma was studied in the optimum conditions (The flow rate was 5 L/min inactivation distance was 2 cm). The results showed that electrically neutral active species was the main factor of inactivation rather than heating effect, ultraviolet radiation and charged particles. Finally the experiments of thallus change proved that microplasma jet had etching effect on cell membrane. It also found that microplasma could degrade organic material like protein. Furthermore, the images of scanning electron microscope (SEM) revealed the change of cell morphology step by step in the whole process of inactivation.

Qualitation and Quantitation on Microplasma Jet for Bacteria Inactivation

PubMed Central

Du, ChangMing; Liu, Ya; Huang, YaNi; Li, ZiMing; Men, Rui; Men, Yue; Tang, Jun

2016-01-01

In this work, a self-made microplasma jet system was used to conduct the qualitation and quantitation of inactivation with Escherichia coli as the target bacteria. The logarithmic concentration and the size of antimicrobial rings served as the evaluation parameters, respectively. The effect of various parameters on inactivation effect was studied. The results showed that the majority of bacteria had been inactivated in 30 s. The inactivation effect enhanced and then weakened with the increase of air flow rate, and receded as the extension of treatment distance. The effect with different carrier gases showed as follows: oxygen > air > nitrogen > argon. Meanwhile, the effect of different components of microplasma was studied in the optimum conditions (The flow rate was 5 L/min; inactivation distance was 2 cm). The results showed that electrically neutral active species was the main factor of inactivation rather than heating effect, ultraviolet radiation and charged particles. Finally the experiments of thallus change proved that microplasma jet had etching effect on cell membrane. It also found that microplasma could degrade organic material like protein. Furthermore, the images of scanning electron microscope (SEM) revealed the change of cell morphology step by step in the whole process of inactivation. PMID:26732987

Evaluating the effects of herbicide drift on nontarget terrestrial plants: A case study with mesotrione.

PubMed

Brain, Richard A; Perine, Jeff; Cooke, Catriona; Ellis, Clare Butler; Harrington, Paul; Lane, Andrew; O'Sullivan, Christine; Ledson, Mark

2017-09-01

Nature of exposure is a fundamental driver in nontarget terrestrial plant risk assessment for pesticides; consequently a novel study was designed to generate field-based drift exposure and evaluate corresponding biological effects of the herbicide mesotrione. The approach used a combination of US guideline drift reduction technology and vegetative vigor approaches. In each of 3 independent replicate spray application trials, 10 pots each of lettuce and tomato were placed at distances of 10, 20, 30, 40, and 50 ft (∼3, 6, 9, 12, and 15 m) from the downwind edge of the spray boom. Each application was conducted using a commercial 60-ft (18-m) boom sprayer fitted with TeeJet ® Technologies TTI110025 nozzles, with a nominal application rate of 0.2 lb a.i./A (224 g a.i./ha). The environmental conditions required by the protocol (air temperature 10-30 °C and wind perpendicular to the swath (±30°) blowing toward the plants at a mean wind speed of ≥10 mph [≥4.5 m/s] measured at 2.0 m above the ground) were met for each application. Following exposure, plants were transferred to a greenhouse for the 21-d vegetative vigor phase of the study. Symptoms of phytotoxicity and plant height were assessed at 7, 14, and 21 d after treatment. On completion of the 21-d after treatment assessment, all plants were harvested and dried in an oven to determine shoot dry weight. The biological data indicated that no statistically significant effects were observed at a distance of 30 ft (∼9 m) from mesotrione drift at wind speeds of ≥10 mph (10.9-12.4 mph); this endpoint (30 ft) is defined as the no observed effects distance (NOED). Environ Toxicol Chem 2017;36:2465-2475. © 2017 SETAC. © 2017 SETAC.

Ranging in Human Sonar: Effects of Additional Early Reflections and Exploratory Head Movements

PubMed Central

Wallmeier, Ludwig; Wiegrebe, Lutz

2014-01-01

Many blind people rely on echoes from self-produced sounds to assess their environment. It has been shown that human subjects can use echolocation for directional localization and orientation in a room, but echo-acoustic distance perception - e.g. to determine one's position in a room - has received little scientific attention, and systematic studies on the influence of additional early reflections and exploratory head movements are lacking. This study investigates echo-acoustic distance discrimination in virtual echo-acoustic space, using the impulse responses of a real corridor. Six blindfolded sighted subjects and a blind echolocation expert had to discriminate between two positions in the virtual corridor, which differed by their distance to the front wall, but not to the lateral walls. To solve this task, participants evaluated echoes that were generated in real time from self-produced vocalizations. Across experimental conditions, we systematically varied the restrictions for head rotations, the subjects' orientation in virtual space and the reference position. Three key results were observed. First, all participants successfully solved the task with discrimination thresholds below 1 m for all reference distances (0.75–4 m). Performance was best for the smallest reference distance of 0.75 m, with thresholds around 20 cm. Second, distance discrimination performance was relatively robust against additional early reflections, compared to other echolocation tasks like directional localization. Third, free head rotations during echolocation can improve distance discrimination performance in complex environmental settings. However, head movements do not necessarily provide a benefit over static echolocation from an optimal single orientation. These results show that accurate distance discrimination through echolocation is possible over a wide range of reference distances and environmental conditions. This is an important functional benefit of human echolocation, which may also play a major role in the calibration of auditory space representations. PMID:25551226

Distance Measurements In X-Ray Pictures

NASA Astrophysics Data System (ADS)

Forsgren, Per-Ola

1987-10-01

In this paper, a measurement method for the distance between binary objects will be presented. It has been developed for a specific purpose, the evaluation of rheumatic disease, but should be useful also in other applications. It is based on a distance map in the area between binary objects. A skeleton is extracted from the distance map by searching for local maxima. The distance measure is based on the average of skelton points in a defined measurement area. An objective criterion for selection of measurement points on the skeleton is proposed. Preliminary results indicate that good repeatability is attained.

Ecosystem engineering of harvester ants: effects on vegetation in a sagebrush-steppe ecosystem

USGS Publications Warehouse

Gosselin, Elyce N; Holbrook, Joseph D.; Huggler, Katey; Brown, Emily; Vierling, Kerri T.; Arkle, Robert; Pilliod, David S.

2016-01-01

Harvester ants are influential in many ecosystems because they distribute and consume seeds, remove vegetation, and redistribute soil particles and nutrients. Understanding the interaction between harvester ants and plant communities is important for management and restoration efforts, particularly in systems altered by fire and invasive species such as the sagebrush-steppe. Our objective was to evaluate how vegetation cover changed as a function of distance from Owyhee harvester ant (Pogonomyrmex salinus) nests within a sagebrush-steppe ecosystem. We sampled 105 harvester ant nests within southern Idaho, USA, that occurred in different habitats: annual grassland, perennial grassland, and native shrubland. The influence of Owyhee harvester ants on vegetation was larger at the edge of ant nests, but the relationship was inconsistent among plant species. Percent cover was positively associated with distance from harvester ant nests for plant species that were considered undesirable food sources and were densely distributed. However, percent cover was negatively associated with distance-from-nests for patchily distributed and desirable plant species. For some plant species, there was no change in cover associated with distance-from-nests. Total vegetation cover was associated with distance-from-nests in the shrubland habitat but not in the 2 grasslands. The dominant plant species in the shrubland habitat was a densely distributed shrub (winterfat, Krascheninnikovia lanata) that was defoliated by harvester ants. Our results suggest that Owyhee harvester ants increase spatial heterogeneity in plant communities through plant clearing, but the direction and magnitude of effect will likely be contingent on the dominant vegetation groups. This information may inform future management and plant restoration efforts in sagebrush-steppe by directly considering the islands of influence associated with harvester ant engineering.

Do We Really Need to Wear Proper Eye Protection When Using Holmium:YAG Laser During Endourologic Procedures? Results from an Ex Vivo Animal Model on Pig Eyes.

PubMed

Villa, Luca; Cloutier, Jonathan; Compérat, Eva; Kronemberg, Peter; Charlotte, Frederic; Berthe, Laurent; Rouchausse, Yann; Salonia, Andrea; Montorsi, Francesco; Traxer, Olivier

2016-03-01

We sought to evaluate the effect of holmium:yttrium-aluminum-garnet (Ho:YAG) laser exposure on ex vivo pig eyes and to test the protective action of different glasses in preventing eye lesions in case of accident. We pointed the tip of a Ho:YAG laser fiber from different distances (0, 3, 5, 8, 10, and 20 cm, respectively) toward the center of the pupil of the pig eye. The Ho:YAG laser was activated for 1 or 5 seconds at three different settings (0.5 J-20 Hz, 1 J-10 Hz, and 2 J-10 Hz, respectively). The experiment was repeated using laser safety glasses and eyeglasses. A total of 78 pig eyes were used. The effects of the Ho:YAG laser on pig eyes were assessed by histopathology. Comparable laser emission experiments were performed on thermal paper at different distances using different pulse energies. Ho:YAG laser-induced corneal lesions were observed in unprotected eyes, ranging from superficial burning lesions to full-thickness necrotic areas, and were directly related to pulse energy and time of exposure and inversely related to the distance from the eye. When the laser was placed 5 cm or more, no corneal damage was observed regardless of the laser setting and the time of exposure. Similar distance/energy level relationships were observed on thermal paper. No damage was observed to the lens or the retina in any of the Ho-YAG laser-treated eyes or in any of the eyes protected by laser safety and eyeglasses. Ho:YAG lasers can cause damage when set to high energy, but only to the cornea, from close distances (0-5 cm) and in the absence of eye protection. Eyeglasses are equally effective in preventing laser damage as laser safety glasses.

SU-E-J-219: Quantitative Evaluation of Motion Effects On Accuracy of Image-Guided Radiotherapy with Fiducial Markers Using CT Imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ali, I; Oyewale, S; Ahmad, S

2014-06-01

Purpose: To investigate quantitatively patient motion effects on the localization accuracy of image-guided radiation with fiducial markers using axial CT (ACT), helical CT (HCT) and cone-beam CT (CBCT) using modeling and experimental phantom studies. Methods: Markers with different lengths (2.5 mm, 5 mm, 10 mm, and 20 mm) were inserted in a mobile thorax phantom which was imaged using ACT, HCT and CBCT. The phantom moved with sinusoidal motion with amplitudes ranging 0–20 mm and a frequency of 15 cycles-per-minute. Three parameters that include: apparent marker lengths, center position and distance between the centers of the markers were measured inmore » the different CT images of the mobile phantom. A motion mathematical model was derived to predict the variations in the previous three parameters and their dependence on the motion in the different imaging modalities. Results: In CBCT, the measured marker lengths increased linearly with increase in motion amplitude. For example, the apparent length of the 10 mm marker was about 20 mm when phantom moved with amplitude of 5 mm. Although the markers have elongated, the center position and the distance between markers remained at the same position for different motion amplitudes in CBCT. These parameters were not affected by motion frequency and phase in CBCT. In HCT and ACT, the measured marker length, center and distance between markers varied irregularly with motion parameters. The apparent lengths of the markers varied with inverse of the phantom velocity which depends on motion frequency and phase. Similarly the center position and distance between markers varied inversely with phantom speed. Conclusion: Motion may lead to variations in maker length, center position and distance between markers using CT imaging. These effects should be considered in patient setup using image-guided radiation therapy based on fiducial markers matching using 2D-radiographs or volumetric CT imaging.« less

The Positive Effect of Authoritarian Leadership on Employee Performance: The Moderating Role of Power Distance.

PubMed

Wang, Honglei; Guan, Bichen

2018-01-01

Based on goal setting theory, this study explores the positive effect and influencing process of authoritarian leadership on employee performance, as well as the moderating role of individual power distance in this process. Data from 211 supervisor-subordinate dyads in Chinese organizations indicates that authoritarian leadership is positively associated with employee performance, and learning goal orientation mediates this relationship. Furthermore, power distance moderates the effect of authoritarian leadership on learning goal orientation, such that the effect was stronger when individual power distance was higher. The indirect effect of authoritarian leadership on employee performance via learning goal orientation is also moderated by power distance. Theoretical and managerial implications and future directions are also discussed.

The Positive Effect of Authoritarian Leadership on Employee Performance: The Moderating Role of Power Distance

PubMed Central

Wang, Honglei; Guan, Bichen

2018-01-01

Based on goal setting theory, this study explores the positive effect and influencing process of authoritarian leadership on employee performance, as well as the moderating role of individual power distance in this process. Data from 211 supervisor-subordinate dyads in Chinese organizations indicates that authoritarian leadership is positively associated with employee performance, and learning goal orientation mediates this relationship. Furthermore, power distance moderates the effect of authoritarian leadership on learning goal orientation, such that the effect was stronger when individual power distance was higher. The indirect effect of authoritarian leadership on employee performance via learning goal orientation is also moderated by power distance. Theoretical and managerial implications and future directions are also discussed. PMID:29628902

Designing multifocal corneal models to correct presbyopia by laser ablation

NASA Astrophysics Data System (ADS)

Alarcón, Aixa; Anera, Rosario G.; Del Barco, Luis Jiménez; Jiménez, José R.

2012-01-01

Two multifocal corneal models and an aspheric model designed to correct presbyopia by corneal photoablation were evaluated. The design of each model was optimized to achieve the best visual quality possible for both near and distance vision. In addition, we evaluated the effect of myosis and pupil decentration on visual quality. The corrected model with the central zone for near vision provides better results since it requires less ablated corneal surface area, permits higher addition values, presents stabler visual quality with pupil-size variations and lower high-order aberrations.

Evaluation for relationship among source parameters of underground nuclear tests in Northern Korean Peninsula

NASA Astrophysics Data System (ADS)

Kim, G.; Che, I. Y.

2017-12-01

We evaluated relationship among source parameters of underground nuclear tests in northern Korean Peninsula using regional seismic data. Dense global and regional seismic networks are incorporated to measure locations and origin times precisely. Location analyses show that distance among the locations is tiny on a regional scale. The tiny location-differences validate a linear model assumption. We estimated source spectral ratios by excluding path effects based spectral ratios of the observed seismograms. We estimated empirical relationship among depth of burials and yields based on theoretical source models.

Effects of multiple concurrent stressors on rectal temperature, blood acid-base status, and longissimus muscle glycolytic potential in market-weight pigs.

PubMed

Ritter, M J; Ellis, M; Anderson, D B; Curtis, S E; Keffaber, K K; Killefer, J; McKeith, F K; Murphy, C M; Peterson, B A

2009-01-01

Sixty-four market-weight (130.0 +/- 0.65 kg) barrows (n = 16) and gilts (n = 48) were used in a split-plot design with a 2 x 2 x 2 factorial arrangement of treatments: 1) handling intensity (gentle vs. aggressive), 2) transport floor space (0.39 vs. 0.49 m(2)/pig), and 3) distance moved during handling (25 vs. 125 m) to determine the effects of multiple concurrent stressors on metabolic responses. For the handling intensity treatment, pigs were moved individually approximately 50 m through a handling course with either 0 (gentle) or 8 (aggressive) shocks from an electric goad. Pigs were loaded onto a trailer and transported for approximately 1 h at floor spaces of either 0.39 or 0.49 m(2)/pig. After transport, pigs were unloaded, and the distance moved treatment was applied; pigs were moved 25 or 125 m through a handling course using livestock paddles. Rectal temperature was measured, and blood samples (to measure blood acid-base status) were collected 2 h before the handling intensity treatment was applied and immediately after the distance moved treatment was applied. A LM sample to measure glycolytic potential was collected after the distance moved treatments on a subset of 32 pigs. There were handling intensity x distance moved interactions (P < 0.05) for several blood acid-base measurements. In general, there was no effect of distance moved on these traits when pigs were previously handled gently. However, when pigs were previously handled aggressively, pigs moved 125 compared with 25 m had greater (P < 0.05) blood lactate and less (P < 0.05) blood pH, bicarbonate, and base-excess. Pigs transported at 0.39 compared with 0.49 m(2)/pig had a greater (P < 0.01) increase in creatine kinase values; however, transport floor space did not affect any other measurements. Data were analyzed by the number of stressors (the aggressive handling, restricted transport floor space, and 125-m distance moved treatments) experienced by each pig (0, 1, 2, or 3). As the number of stressors experienced by the pig increased, rectal temperature, blood lactate, and LM lactate increased linearly (P

Effects of burstiness on the air transportation system

NASA Astrophysics Data System (ADS)

Ito, Hidetaka; Nishinari, Katsuhiro

2017-01-01

The effects of burstiness in complex networks have received considerable attention. In particular, the effects on temporal distance and delays in the air transportation system are significant owing to their huge impact on our society. Therefore, in this paper, the temporal distance of empirical U.S. flight schedule data is compared with that of regularized data without burstiness to analyze the effects of burstiness. The temporal distance is calculated by a graph analysis method considering flight delays, missed connections, flight cancellations, and congestion. In addition, we propose two temporal distance indexes based on passengers' behavior to quantify the effects. As a result, we find that burstiness reduces both the scheduled and the actual temporal distances for business travelers, while delays caused by missed connections and congestion are increased. We also find that the decrease of the scheduled temporal distance by burstiness is offset by an increase of the delays for leisure passengers. Moreover, we discover that the positive effect of burstiness is lost when flight schedules are overcrowded.

Effects of burstiness on the air transportation system.

PubMed

Ito, Hidetaka; Nishinari, Katsuhiro

2017-01-01

The effects of burstiness in complex networks have received considerable attention. In particular, the effects on temporal distance and delays in the air transportation system are significant owing to their huge impact on our society. Therefore, in this paper, the temporal distance of empirical U.S. flight schedule data is compared with that of regularized data without burstiness to analyze the effects of burstiness. The temporal distance is calculated by a graph analysis method considering flight delays, missed connections, flight cancellations, and congestion. In addition, we propose two temporal distance indexes based on passengers' behavior to quantify the effects. As a result, we find that burstiness reduces both the scheduled and the actual temporal distances for business travelers, while delays caused by missed connections and congestion are increased. We also find that the decrease of the scheduled temporal distance by burstiness is offset by an increase of the delays for leisure passengers. Moreover, we discover that the positive effect of burstiness is lost when flight schedules are overcrowded.

Inhibition of demineralization around the enamel-dentin/restoration interface after dentin pretreatment with TiF4 and self-etching adhesive systems.

PubMed

Bridi, Enrico Coser; do Amaral, Flávia Lucisano Botelho; França, Fabiana Mantovani Gomes; Turssi, Cecilia Pedroso; Basting, Roberta Tarkany

2016-05-01

The objective of this study was to evaluate the inhibition of demineralization around enamel-dentin/restoration interface after dentin pretreatment with 2.5% titanium tetrafluoride (TiF4). Forty dental class V cavities at the cementoenamel junction were distributed into four groups (n = 10), according to the presence or absence of TiF4 and to the adhesive system (Clearfil SE Bond/CL and Adper EasyOne/AD), and restored with a resin composite. A dynamic pH cycling model was used to induce the development of artificial caries lesions. After sectioning the dental blocks, Knoop microhardness tests were performed at different depths (20, 40, and 60 μm from the occlusal margin of the restoration) and at different distances (100, 200, and 300 μm from the adhesive interface). Repeated measures three-way analysis of variance (ANOVA) and Tukey's test were used (α = 0.05). For enamel, there were no differences in the microhardness values for CL, AD, and TiF4-AD at depths, regardless of the distances. Considering each depth, there were no significant differences among treatments. For dentin, ANOVA showed no significant interaction among the independent variables treatment*distance*depth (p = 0.994), no significant interaction between treatment*depth (p = 0.722), no significant interaction between treatment*distance (p = 0.265), no significant interaction between depth*distance (p = 0.365), and no significant effect on treatment (p = 0.151), depth (p = 0.067), or distance (p = 0.251). Dentin pretreatment of the cavity walls with TiF4 before self-etching adhesive systems was not effective in inhibiting demineralization around the enamel-dentin/restoration interfaces. The mechanism of incorporating fluoride in enamel and dentin of the cavity walls to inhibit demineralization around restorations seems ineffective when using TiF4 as a dentin pretreatment.

Evaluation on Cost Overrun Risks of Long-distance Water Diversion Project Based on SPA-IAHP Method

NASA Astrophysics Data System (ADS)

Yuanyue, Yang; Huimin, Li

2018-02-01

Large investment, long route, many change orders and etc. are main causes for costs overrun of long-distance water diversion project. This paper, based on existing research, builds a full-process cost overrun risk evaluation index system for water diversion project, apply SPA-IAHP method to set up cost overrun risk evaluation mode, calculate and rank weight of every risk evaluation indexes. Finally, the cost overrun risks are comprehensively evaluated by calculating linkage measure, and comprehensive risk level is acquired. SPA-IAHP method can accurately evaluate risks, and the reliability is high. By case calculation and verification, it can provide valid cost overrun decision making information to construction companies.

The Molecular Structure of cis-FONO

NASA Technical Reports Server (NTRS)

Lee, Timothy J.; Dateo, Christopher E.; Rice, Julia E.; Langhoff, Stephen R. (Technical Monitor)

1994-01-01

The molecular structure of cis-FONO has been determined with the CCSD(T) correlation method using an spdf quality basis set. In agreement with previous coupled-cluster calculations but in disagreement with density functional theory, cis-FONO is found to exhibit normal bond distances. The quadratic and cubic force fields of cis-FONO have also been determined in order to evaluate the effect of vibrational averaging on the molecular geometry. Vibrational averaging is found to increase bond distances, as expected, but it does not affect the qualitative nature of the bonding. The CCSD(T)/spdf harmonic frequencies of cis-FONO support our previous assertion that a band observed at 1200 /cm is a combination band (upsilon(sub 3) + upsilon(sub 4)), and not a fundamental.

A Discriminant Distance Based Composite Vector Selection Method for Odor Classification

PubMed Central

Choi, Sang-Il; Jeong, Gu-Min

2014-01-01

We present a composite vector selection method for an effective electronic nose system that performs well even in noisy environments. Each composite vector generated from a electronic nose data sample is evaluated by computing the discriminant distance. By quantitatively measuring the amount of discriminative information in each composite vector, composite vectors containing informative variables can be distinguished and the final composite features for odor classification are extracted using the selected composite vectors. Using the only informative composite vectors can be also helpful to extract better composite features instead of using all the generated composite vectors. Experimental results with different volatile organic compound data show that the proposed system has good classification performance even in a noisy environment compared to other methods. PMID:24747735

Gaussian geometric discord in terms of Hellinger distance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suciu, Serban, E-mail: serban.suciu@theory.nipne.ro; Isar, Aurelian

2015-12-07

In the framework of the theory of open systems based on completely positive quantum dynamical semigroups, we address the quantification of general non-classical correlations in Gaussian states of continuous variable systems from a geometric perspective. We give a description of the Gaussian geometric discord by using the Hellinger distance as a measure for quantum correlations between two non-interacting non-resonant bosonic modes embedded in a thermal environment. We evaluate the Gaussian geometric discord by taking two-mode squeezed thermal states as initial states of the system and show that it has finite values between 0 and 1 and that it decays asymptoticallymore » to zero in time under the effect of the thermal bath.« less

Interactive effects of temperature and glyphosate on the behavior of blue ridge two-lined salamanders (Eurycea wilderae).

PubMed

Gandhi, Jaina S; Cecala, Kristen K

2016-09-01

The objective of the present study was to evaluate the potential interactive effects of stream temperatures and environmentally relevant glyphosate-based herbicide concentrations on movement and antipredator behaviors of larval Eurycea wilderae (Blue Ridge two-lined salamander). Larval salamanders were exposed to 1 of 4 environmentally relevant glyphosate concentrations (0.00 µg acid equivalent [a.e.]/L, 0.73 µg a.e./L, 1.46 µg a.e./L, and 2.92 µg a.e./L) at either ambient (12 °C) or elevated (23 °C) water temperature. Behaviors observed included the exploration of a novel habitat, use of refuge, habitat selection relative to a potential predator, and burst movement distance. In the absence of glyphosate, temperature consistently affected movement and refuge-use behavior, with individuals moving longer distances more frequently and using refuge less at warm temperatures; however, when glyphosate was added, the authors observed inconsistent effects of temperature that may have resulted from differential toxicity at various temperatures. Larval salamanders made shorter, more frequent movements and demonstrated reduced burst distance at higher glyphosate concentrations. The authors also found that lower glyphosate concentrations sometimes had stronger effects than higher concentrations (i.e., nonmonotonic dose responses), suggesting that standard safety tests conducted only at higher glyphosate concentrations might overlook important sublethal effects on salamander behavior. These data demonstrate that sublethal effects of glyphosate-based herbicides on natural behaviors of amphibians can occur with short-term exposure to environmentally relevant concentrations. Environ Toxicol Chem 2016;35:2297-2303. © 2016 SETAC. © 2016 SETAC.

An Evaluation of the Impact of "Learning Design" on the Distance Learning and Teaching Experience

ERIC Educational Resources Information Center

Clifton, Grace

2017-01-01

This paper evaluates the implementation of Learning Design on the production of a core FHEQ level 6 (QAA, 2008) unit of study at a UK distance learning institution. By comparing student (n = 656) and tutor (n = 42) survey data with questionnaire responses (n = 9) from the unit of study's core production team, this paper assesses the impact of…

Estimating abundance of mountain lions from unstructured spatial sampling

USGS Publications Warehouse

Russell, Robin E.; Royle, J. Andrew; Desimone, Richard; Schwartz, Michael K.; Edwards, Victoria L.; Pilgrim, Kristy P.; Mckelvey, Kevin S.

2012-01-01

Mountain lions (Puma concolor) are often difficult to monitor because of their low capture probabilities, extensive movements, and large territories. Methods for estimating the abundance of this species are needed to assess population status, determine harvest levels, evaluate the impacts of management actions on populations, and derive conservation and management strategies. Traditional mark–recapture methods do not explicitly account for differences in individual capture probabilities due to the spatial distribution of individuals in relation to survey effort (or trap locations). However, recent advances in the analysis of capture–recapture data have produced methods estimating abundance and density of animals from spatially explicit capture–recapture data that account for heterogeneity in capture probabilities due to the spatial organization of individuals and traps. We adapt recently developed spatial capture–recapture models to estimate density and abundance of mountain lions in western Montana. Volunteers and state agency personnel collected mountain lion DNA samples in portions of the Blackfoot drainage (7,908 km2) in west-central Montana using 2 methods: snow back-tracking mountain lion tracks to collect hair samples and biopsy darting treed mountain lions to obtain tissue samples. Overall, we recorded 72 individual capture events, including captures both with and without tissue sample collection and hair samples resulting in the identification of 50 individual mountain lions (30 females, 19 males, and 1 unknown sex individual). We estimated lion densities from 8 models containing effects of distance, sex, and survey effort on detection probability. Our population density estimates ranged from a minimum of 3.7 mountain lions/100 km2 (95% Cl 2.3–5.7) under the distance only model (including only an effect of distance on detection probability) to 6.7 (95% Cl 3.1–11.0) under the full model (including effects of distance, sex, survey effort, and distance x sex on detection probability). These numbers translate to a total estimate of 293 mountain lions (95% Cl 182–451) to 529 (95% Cl 245–870) within the Blackfoot drainage. Results from the distance model are similar to previous estimates of 3.6 mountain lions/100 km2 for the study area; however, results from all other models indicated greater numbers of mountain lions. Our results indicate that unstructured spatial sampling combined with spatial capture–recapture analysis can be an effective method for estimating large carnivore densities.

Factors affecting measurement of optic parameters by time-resolved near-infrared spectroscopy in breast cancer

NASA Astrophysics Data System (ADS)

Yoshizawa, Nobuko; Ueda, Yukio; Mimura, Tetsuya; Ohmae, Etsuko; Yoshimoto, Kenji; Wada, Hiroko; Ogura, Hiroyuki; Sakahara, Harumi

2018-02-01

The purpose of this study was to evaluate the effects of the thickness and depth of tumors on hemoglobin measurements in breast cancer by optical spectroscopy and to demonstrate tissue oxygen saturation (SO2) and reduced scattering coefficient (μs‧) in breast tissue and breast cancer in relation to the skin-to-chest wall distance. We examined 53 tumors from 44 patients. Total hemoglobin concentration (tHb), SO2, and μs‧ were measured by time-resolved spectroscopy (TRS). The skin-to-chest wall distance and the size and depth of tumors were measured by ultrasonography. There was a positive correlation between tHb and tumor thickness, and a negative correlation between tHb and tumor depth. SO2 in breast tissue decreased when the skin-to-chest wall distance decreased, and SO2 in tumors tended to be lower than in breast tissue. In breast tissue, there was a negative correlation between μs‧ and the skin-to-chest wall distance, and μs‧ in tumors was higher than in breast tissue. Measurement of tHb in breast cancer by TRS was influenced by tumor thickness and depth. Although SO2 seemed lower and μs‧ was higher in breast cancer than in breast tissue, the skin-to-chest wall distance may have affected the measurements.

Abstract Mindsets Increase Believability of Spatially Distant Online Messages

PubMed Central

Sungur, Hande; Hartmann, Tilo; van Koningsbruggen, Guido M.

2016-01-01

Growing evidence from online credibility research reveals that online users rely on heuristic processes to evaluate the credibility of online information. The current paper, which is based on the construal level theory (CLT), proposes that congruency between the psychological distance of a stimulus and the way it is mentally construed can act as a heuristic for believability. According to CLT, psychologically close (e.g., spatially, temporally, socially) stimuli are represented concretely whereas psychologically distant stimuli are represented abstractly. The level of mental construals and the psychological distance of information have been shown to influence people’s truth judgments in offline contexts. This study tests whether congruency between the construal level of people’s mindsets (abstract vs. concrete) and the psychological distance implied in an online message (far vs. close) enhances message believability. By partially confirming CLT predictions, we found that believability of an online news item about a distant location increased when people maintained an abstract mindset rather than a concrete one. The effect of a concrete mindset on believability was not significant for the close psychological distance condition. Our findings provide initial evidence that congruency between the construal level of people’s mindsets and psychological distance cues in online messages can act as a heuristic for believability. We discuss the potential of applying the CLT framework to the growing literature on online cognitive heuristics in the area of online information credibility. PMID:27468272

Understanding less than nothing: children's neural response to negative numbers shifts across age and accuracy.

PubMed

Gullick, Margaret M; Wolford, George

2013-01-01

We examined the brain activity underlying the development of our understanding of negative numbers, which are amounts lacking direct physical counterparts. Children performed a paired comparison task with positive and negative numbers during an fMRI session. As previously shown in adults, both pre-instruction fifth-graders and post-instruction seventh-graders demonstrated typical behavioral and neural distance effects to negative numbers, where response times and parietal and frontal activity increased as comparison distance decreased. We then determined the factors impacting the distance effect in each age group. Behaviorally, the fifth-grader distance effect for negatives was significantly predicted only by positive comparison accuracy, indicating that children who were generally better at working with numbers were better at comparing negatives. In seventh-graders, negative number comparison accuracy significantly predicted their negative number distance effect, indicating that children who were better at working with negative numbers demonstrated a more typical distance effect. Across children, as age increased, the negative number distance effect increased in the bilateral IPS and decreased frontally, indicating a frontoparietal shift consistent with previous numerical development literature. In contrast, as negative comparison task accuracy increased, the parietal distance effect increased in the left IPS and decreased in the right, possibly indicating a change from an approximate understanding of negatives' values to a more exact, precise representation (particularly supported by the left IPS) with increasing expertise. These shifts separately indicate the effects of increasing maturity generally in numeric processing and specifically in negative number understanding.

Effect of course length and corridor width on the 2-minute walk test performance in geriatric patients.

PubMed

Lindemann, Ulrich; Beck, Luisa; Becker, Clemens

2017-02-01

To evaluate the effect of course length and corridor width on 2-minute walk test results in older adults. Cross-sectional and experimental study with different test conditions. Geriatric rehabilitation clinic. A total of 21 patients (median age 81 years). Patients walked two minutes on a 20 m and 40 m course with a 2 m or 1 m corridor width and on a continuous course without any turning in a corridor of 2 m width, five walks in total. The distance traveled within the 2 minutes was recorded. Compared with the 20 m course length, median walking distances measured by the 2-minute walk test in a walk way 2 m broad were better on the continuous corridor without any turn (136.9 m vs. 129.3 m, p = 0.002) and on the 40 m course (131.8 m vs. 129.3 m, p = 0.003). Walking distance on a 20 m course length was longer in a corridor of 2 m width compared with the 1 m corridor width (129.3 m vs. 119.2 m, p = 0.005). The walking distance was not affected by corridor width on the 40 m course length. Performance of elderly patients on the 2-minute walk test is influenced by the width of the corridor and the length of the course used.

Effect of gap distance on tensile strength of preceramic base metal solder joints.

PubMed

Fattahi, Farnaz; Motamedi, Milad

2011-01-01

In order to fabricate prostheses with high accuracy and durability, soldering techniques have been introduced to clinical dentistry. However, these prostheses always fail at their solder joints. The purpose of this study was to evaluate the effect of gap distance on the tensile strength of base metal solder joints. Based on ADA/ISO 9693 specifications for tensile test, 40 specimens were fabricated from a Ni-Cr alloy and cut at the midpoint of 3-mm diameter bar and placed at desired positions by a specially designed device. The specimens were divided into four groups of 10 samples according to the desired solder gap distance: Group1: 0.1mm; Group2: 0.25mm; Group3: 0.5mm; and Group4: 0.75mm. After soldering, specimens were tested for tensile strength by a universal testing machine at a cross-head speed of 0.5mm/min with a preload of 10N. The mean tensile strength values of the groups were 162, 307.8, 206.1 and 336.7 MPa, respectively. The group with 0.75-mm gap had the highest and the group with 0.1-mm gap had the lowest tensile strength. Bonferroni test showed that Group1 and Group4 had statistically different values (P=0.023), but the differences between other groups were not sig-nificant at a significance level of 0.05. There was no direct relationship between increasing soldering gap distance and tensile strength of the solder joints.

An Empirical Jet-Surface Interaction Noise Model with Temperature and Nozzle Aspect Ratio Effects

NASA Technical Reports Server (NTRS)

Brown, Cliff

2015-01-01

An empirical model for jet-surface interaction (JSI) noise produced by a round jet near a flat plate is described and the resulting model evaluated. The model covers unheated and hot jet conditions (1 less than or equal to jet total temperature ratio less than or equal to 2.7) in the subsonic range (0.5 less than or equal to M(sub a) less than or equal to 0.9), surface lengths 0.6 less than or equal to (axial distance from jet exit to surface trailing edge (inches)/nozzle exit diameter) less than or equal to 10, and surface standoff distances (0 less than or equal to (radial distance from jet lipline to surface (inches)/axial distance from jet exit to surface trailing edge (inches)) less than or equal to 1) using only second-order polynomials to provide predictable behavior. The JSI noise model is combined with an existing jet mixing noise model to produce exhaust noise predictions. Fit quality metrics and comparisons to between the predicted and experimental data indicate that the model is suitable for many system level studies. A first-order correction to the JSI source model that accounts for the effect of nozzle aspect ratio is also explored. This correction is based on changes to the potential core length and frequency scaling associated with rectangular nozzles up to 8:1 aspect ratio. However, more work is needed to refine these findings into a formal model.

Failure mode and effects analysis using intuitionistic fuzzy hybrid weighted Euclidean distance operator

NASA Astrophysics Data System (ADS)

Liu, Hu-Chen; Liu, Long; Li, Ping

2014-10-01

Failure mode and effects analysis (FMEA) has shown its effectiveness in examining potential failures in products, process, designs or services and has been extensively used for safety and reliability analysis in a wide range of industries. However, its approach to prioritise failure modes through a crisp risk priority number (RPN) has been criticised as having several shortcomings. The aim of this paper is to develop an efficient and comprehensive risk assessment methodology using intuitionistic fuzzy hybrid weighted Euclidean distance (IFHWED) operator to overcome the limitations and improve the effectiveness of the traditional FMEA. The diversified and uncertain assessments given by FMEA team members are treated as linguistic terms expressed in intuitionistic fuzzy numbers (IFNs). Intuitionistic fuzzy weighted averaging (IFWA) operator is used to aggregate the FMEA team members' individual assessments into a group assessment. IFHWED operator is applied thereafter to the prioritisation and selection of failure modes. Particularly, both subjective and objective weights of risk factors are considered during the risk evaluation process. A numerical example for risk assessment is given to illustrate the proposed method finally.

Laboratory evaluation of the Design Analysis Associates DAA H-3613i radar water-level sensor—Results of temperature, distance, and SDI-12 tests

USGS Publications Warehouse

Carnley, Mark V.

2016-09-30

The Design Analysis Associates (DAA) DAA H-3613i radar water-level sensor (DAA H-3613i), manufactured by Xylem Incorporated, was evaluated by the U.S. Geological Survey (USGS) Hydrologic Instrumentation Facility (HIF) for conformance to manufacturer’s accuracy specifications for measuring a distance throughout the sensor’s operating temperature range, for measuring distances from 3 to 15 feet at ambient temperatures, and for compliance with the SDI-12 serial-to-digital interface at 1200-baud communication standard. The DAA H-3613i is a noncontact water-level sensor that uses pulsed radar to measure the distance between the radar and the water surface from 0.75 to 131 feet over a temperature range of −40 to 60 degrees Celsius (°C). Manufacturer accuracy specifications that were evaluated, the test procedures that followed, and the results obtained are described in this report. The sensor’s accuracy specification of ± 0.01 feet (± 3 millimeters) meets USGS requirements for a primary water-stage sensor used in the operation of a streamgage. The sensor met the manufacturer’s stated accuracy specifications for water-level measurements during temperature testing at a distance of 8 feet from the target over its temperature-compensated operating range of −40 to 60 °C, except at 60 °C. At 60 °C, about half the measurements exceeded the manufacturer’s accuracy specification by not more than 0.005 feet.The sensor met the manufacturer’s stated accuracy specifications for water-level measurements during distance-accuracy testing at the tested distances from 3 to 15 feet above the water surface at the HIF.

Sensors closeness test based on an improved [0, 1] bounded Mahalanobis distance Δ{sup 2}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Masnan, Maz Jamilah, E-mail: mazjamilah@unimap.edu.my; Mahat, Nor Idayu, E-mail: noridayu@uum.edu.my; Shakaff, Ali Yeon Md, E-mail: aliyeon@unimap.edu.my

2015-12-11

Mahalanobis distance Δ{sup 2} values are commonly in the range of 0 to +∞ where higher values represent greater distance between class means or points. The increase in Mahalanobis distance is unbounded as the distance multiply. To certain extend, the unbounded distance values pose difficulties in the evaluation and decision for instance in the sensors closeness test. This paper proposes an approach to [0, 1] bounded Mahalanobis distance Δ{sup 2} that enable researcher to easily perform sensors closeness test. The experimental data of four different types of rice based on three different electronic nose sensors namely InSniff, PEN3, and Cyranose320more » were analyzed and sensor closeness test seems successfully performed within the [0, 1] bound.« less

Distance Education Programs in Texas Community & Technical Colleges: Assessing Student Support Services in a Virtual Environment.

ERIC Educational Resources Information Center

Luedtke, Cherry Beth

This project evaluates the status of distance learning at 54 public, two-year community, and technical colleges in Texas. Data was collected from the Web sites of each of the institutions. The Web site data indicted that 44 of the colleges refer specifically to distance education courses offered. To assess what student support services are…

Evaluation of Library Utilization by Students Enrolled in External Degree Programme in University of Nairobi, Kenya

ERIC Educational Resources Information Center

Gor, Peter Ochieng

2012-01-01

With the increasing popularity of distance education, focus has turned to the role of libraries in distance learning process. It is widely agreed that like their campus-based counterparts, distance education learners need adequate library services if they are to gain quality education. This study sought to examine library utilization by students…

Assessment of Students' Ratings for Two Methodologies of Teaching via Distance Learning: An Evaluative Approach Based on Accreditation.

ERIC Educational Resources Information Center

Restauri, Sherri L.; King, Franklin L.; Nelson, J. Gordon

Two of the most popular delivery formats in distance education are video conferencing and online methodologies. The first step in the processes of recognition and reorganization needed for both forms of distance education is to identify the differences between the traditional classroom environment and the classroom that is augmented or replaced by…

Determining the Feasibility of an E-Portfolio Application in a Distance Education Teaching Practice Course

ERIC Educational Resources Information Center

Kecik, Ilknur; Aydin, Belgin; Sakar, Nurhan; Dikdere, Mine; Aydin, Sinan; Yuksel, Ilknur; Caner, Mustafa

2012-01-01

In this study we aim to conduct a complete evaluation of the e-portfolio application in the distance teaching practice course that is part of the Distance English Language Teacher (DELT) program at Anadolu University from the perspective of three groups: university supervisors, preservice teachers, and cooperating teachers. Using a survey on the…

THE INFLUENCE OF REFRACTIVE ERROR MANAGEMENT ON THE NATURAL HISTORY AND TREATMENT OUTCOME OF ACCOMMODATIVE ESOTROPIA (AN AMERICAN OPHTHALMOLOGICAL SOCIETY THESIS)

PubMed Central

Black, Bradley Charles

2006-01-01

Purpose To evaluate the effect of refractive error management on resolution of accommodative esotropia, deterioration of accommodative esotropia, and the natural history of hypermetropia in accommodative esotropia. Methods Retrospective cohort study and nested case-control study of patients with accommodative esotropia untreated prior to diagnosis by the author. Eligibility criteria included esodeviation of ≥10 prism diopters (PD) on distance and near fixation on initial examination, hypermetropia, distance esodeviation <10 PD with full cycloplegic refraction correction on first follow-up examination, and at least 2 years of follow-up. Results The study included 285 patients with mean follow-up of 102 months. After age 7 years, mean annual decrease in hypermetropia was .24 D for patients wearing full cycloplegic refraction and for patients in whom hypermetropia was undercorrected by 1.00 D or more. Age at diagnosis (P < .0001), oblique muscle dysfunction (P < .0001), and abnormal distance-near relationship (P = .007) were associated with deterioration of accommodative esotropia. Of 51 patients with an intermittent abnormal distance-near relationship, 19 (37%) had increased hypermetropia on cycloplegic refraction, and prescription of the increased correction normalized the distance-near relationship. Conclusions The possibility that undercorrecting hypermetropia speeds its resolution is not supported by this study. Accommodative esotropia is usually stable, but younger age at diagnosis, oblique muscle dysfunction, and abnormal distance-near relationship are associated with deterioration. Undercorrection of hypermetropia can cause an abnormal distance-near relationship, which in turn can cause deterioration of accommodative esotropia. Aggressive undercorrection of hypermetropia should be pursued carefully, because the risk may outweigh the potential advantages. PMID:17471349

Distance Decay of Similarity in Neotropical Diatom Communities

PubMed Central

Wetzel, Carlos E.; Bicudo, Denise de C.; Ector, Luc; Lobo, Eduardo A.; Soininen, Janne; Landeiro, Victor L.; Bini, Luis M.

2012-01-01

Background The regression of similarity against distance unites several ecological phenomena, and thus provides a highly useful approach for illustrating the spatial turnover across sites. Our aim was to test whether the rates of decay in community similarity differ between diatom growth forms suggested to show different dispersal ability. We hypothesized that the diatom group with lower dispersal ability (i.e. periphyton) would show higher distance decay rates than a group with higher dispersal ability (i.e. plankton). Methods/Principal findings Periphyton and phytoplankton samples were gathered at sites distributed over an area of approximately 800 km length in the Negro River, Amazon basin, Brazil, South America (3°08′00″S; 59°54′30″W). Distance decay relationships were then estimated using distance-based regressions, and the coefficients of these regressions were compared among the groups with different dispersal abilities to assess our predictions. We found evidence that different tributaries and reaches of the Negro River harbor different diatom communities. As expected, the rates of distance decay in community similarity were higher for periphyton than for phytoplankton indicating the lower dispersal ability of periphytic taxa. Conclusions/Significance Our study demonstrates that the comparison of distance decay relationships among taxa with similar ecological requirements, but with different growth form and thus dispersal ability provides a sound approach to evaluate the effects of dispersal ability on beta diversity patterns. Our results are also in line with the growing body of evidence indicating that microorganisms exhibit biogeographic patterns. Finally, we underscore that clumbing all microbial taxa into one group may be a flawed approach to test whether microbes exhibit biogeographic patterns. PMID:23028767

Functional connectivity and structural covariance between regions of interest can be measured more accurately using multivariate distance correlation.

PubMed

Geerligs, Linda; Cam-Can; Henson, Richard N

2016-07-15

Studies of brain-wide functional connectivity or structural covariance typically use measures like the Pearson correlation coefficient, applied to data that have been averaged across voxels within regions of interest (ROIs). However, averaging across voxels may result in biased connectivity estimates when there is inhomogeneity within those ROIs, e.g., sub-regions that exhibit different patterns of functional connectivity or structural covariance. Here, we propose a new measure based on "distance correlation"; a test of multivariate dependence of high dimensional vectors, which allows for both linear and non-linear dependencies. We used simulations to show how distance correlation out-performs Pearson correlation in the face of inhomogeneous ROIs. To evaluate this new measure on real data, we use resting-state fMRI scans and T1 structural scans from 2 sessions on each of 214 participants from the Cambridge Centre for Ageing & Neuroscience (Cam-CAN) project. Pearson correlation and distance correlation showed similar average connectivity patterns, for both functional connectivity and structural covariance. Nevertheless, distance correlation was shown to be 1) more reliable across sessions, 2) more similar across participants, and 3) more robust to different sets of ROIs. Moreover, we found that the similarity between functional connectivity and structural covariance estimates was higher for distance correlation compared to Pearson correlation. We also explored the relative effects of different preprocessing options and motion artefacts on functional connectivity. Because distance correlation is easy to implement and fast to compute, it is a promising alternative to Pearson correlations for investigating ROI-based brain-wide connectivity patterns, for functional as well as structural data. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Effect of Proximity to a Cattle Feedlot on Escherichia coli O157:H7 Contamination of Leafy Greens and Evaluation of the Potential for Airborne Transmission

PubMed Central

Wells, James E.; Bono, James L.; Woodbury, Bryan L.; Kalchayanand, Norasak; Norman, Keri N.; Suslow, Trevor V.; López-Velasco, Gabriela; Millner, Patricia D.

2014-01-01

The impact of proximity to a beef cattle feedlot on Escherichia coli O157:H7 contamination of leafy greens was examined. In each of 2 years, leafy greens were planted in nine plots located 60, 120, and 180 m from a cattle feedlot (3 plots at each distance). Leafy greens (270) and feedlot manure samples (100) were collected six different times from June to September in each year. Both E. coli O157:H7 and total E. coli bacteria were recovered from leafy greens at all plot distances. E. coli O157:H7 was recovered from 3.5% of leafy green samples per plot at 60 m, which was higher (P < 0.05) than the 1.8% of positive samples per plot at 180 m, indicating a decrease in contamination as distance from the feedlot was increased. Although E. coli O157:H7 was not recovered from air samples at any distance, total E. coli was recovered from air samples at the feedlot edge and all plot distances, indicating that airborne transport of the pathogen can occur. Results suggest that risk for airborne transport of E. coli O157:H7 from cattle production is increased when cattle pen surfaces are very dry and when this situation is combined with cattle management or cattle behaviors that generate airborne dust. Current leafy green field distance guidelines of 120 m (400 feet) may not be adequate to limit the transmission of E. coli O157:H7 to produce crops planted near concentrated animal feeding operations. Additional research is needed to determine safe set-back distances between cattle feedlots and crop production that will reduce fresh produce contamination. PMID:25452286

[A New Distance Metric between Different Stellar Spectra: the Residual Distribution Distance].

PubMed

Liu, Jie; Pan, Jing-chang; Luo, A-li; Wei, Peng; Liu, Meng

2015-12-01

Distance metric is an important issue for the spectroscopic survey data processing, which defines a calculation method of the distance between two different spectra. Based on this, the classification, clustering, parameter measurement and outlier data mining of spectral data can be carried out. Therefore, the distance measurement method has some effect on the performance of the classification, clustering, parameter measurement and outlier data mining. With the development of large-scale stellar spectral sky surveys, how to define more efficient distance metric on stellar spectra has become a very important issue in the spectral data processing. Based on this problem and fully considering of the characteristics and data features of the stellar spectra, a new distance measurement method of stellar spectra named Residual Distribution Distance is proposed. While using this method to measure the distance, the two spectra are firstly scaled and then the standard deviation of the residual is used the distance. Different from the traditional distance metric calculation methods of stellar spectra, when used to calculate the distance between stellar spectra, this method normalize the two spectra to the same scale, and then calculate the residual corresponding to the same wavelength, and the standard error of the residual spectrum is used as the distance measure. The distance measurement method can be used for stellar classification, clustering and stellar atmospheric physical parameters measurement and so on. This paper takes stellar subcategory classification as an example to test the distance measure method. The results show that the distance defined by the proposed method is more effective to describe the gap between different types of spectra in the classification than other methods, which can be well applied in other related applications. At the same time, this paper also studies the effect of the signal to noise ratio (SNR) on the performance of the proposed method. The result show that the distance is affected by the SNR. The smaller the signal-to-noise ratio is, the greater impact is on the distance; While SNR is larger than 10, the signal-to-noise ratio has little effect on the performance for the classification.

Predicting performance for ecological restoration: A case study using Spartina altemiflora

USGS Publications Warehouse

Travis, S.E.; Grace, J.B.

2010-01-01

The success of population-based ecological restoration relies on the growth and reproductive performance of selected donor materials, whether consisting of whole plants or seed. Accurately predicting performance requires an understanding of a variety of underlying processes, particularly gene flow and selection, which can be measured, at least in part, using surrogates such as neutral marker genetic distances and simple latitudinal effects. Here we apply a structural equation modeling approach to understanding and predicting performance in a widespread salt marsh grass, Spartina alterniflora, commonly used for ecological restoration throughout its native range in North America. We collected source materials from throughout this range, consisting of eight clones each from 23 populations, for transplantation to a common garden site in coastal Louisiana and monitored their performance. We modeled performance as a latent process described by multiple indicator variables (e.g., clone diameter, stem number) and estimated direct and indirect influences of geographic and genetic distances on performance. Genetic distances were determined by comparison of neutral molecular markers with those from a local population at the common garden site. Geographic distance metrics included dispersal distance (the minimum distance over water between donor and experimental sites) and latitude. Model results indicate direct effects of genetic distance and latitude on performance variation among the donor sites. Standardized effect strengths indicate that performance was roughly twice as sensitive to variation in genetic distance as to latitudinal variation. Dispersal distance had an indirect influence on performance through effects on genetic distance, indicating a typical pattern of genetic isolation by distance. Latitude also had an indirect effect on genetic distance through its linear relationship with dispersal distance. Three performance indicators had significant loadings on performance alone (mean clone diameter, mean number of stems, mean number of inflorescences), while the performance indicators mean stem height and mean stem width were also influenced by latitude. We suggest that dispersal distance and latitude should provide an adequate means of predicting performance in future S. alterniflora restorations and propose a maximum sampling distance of 300 km (holding latitude constant) to avoid the sampling of inappropriate ecotypes. ?? 2010 by the Ecological Society of America.

Distancing from experienced self: how global-versus-local perception affects estimation of psychological distance.

PubMed

Liberman, Nira; Förster, Jens

2009-08-01

In 4 studies, the authors examined the prediction derived from construal level theory (CLT) that higher level of perceptual construal would enhance estimated egocentric psychological distance. The authors primed participants with global perception, local perception, or both (the control condition). Relative to the control condition, global processing made participants estimate larger psychological distances in time (Study 1), space (Study 2), social distance (Study 3), and hypotheticality (Study 4). Local processing had the opposite effect. Consistent with CLT, all studies show that the effect of global-versus-local processing did emerge when participants estimated egocentric distances, which are distances from the experienced self in the here and now, but did not emerge with temporal distances not from now (Study 1), spatial distances not from here (Study 2), social distances not from the self (Study 3), or hypothetical events that did not involve altering an experienced reality (Study 4).

Retrieval evaluation and distance learning from perceived similarity between endomicroscopy videos.

PubMed

André, Barbara; Vercauteren, Tom; Buchner, Anna M; Wallace, Michael B; Ayache, Nicholas

2011-01-01

Evaluating content-based retrieval (CBR) is challenging because it requires an adequate ground-truth. When the available groundtruth is limited to textual metadata such as pathological classes, retrieval results can only be evaluated indirectly, for example in terms of classification performance. In this study we first present a tool to generate perceived similarity ground-truth that enables direct evaluation of endomicroscopic video retrieval. This tool uses a four-points Likert scale and collects subjective pairwise similarities perceived by multiple expert observers. We then evaluate against the generated ground-truth a previously developed dense bag-of-visual-words method for endomicroscopic video retrieval. Confirming the results of previous indirect evaluation based on classification, our direct evaluation shows that this method significantly outperforms several other state-of-the-art CBR methods. In a second step, we propose to improve the CBR method by learning an adjusted similarity metric from the perceived similarity ground-truth. By minimizing a margin-based cost function that differentiates similar and dissimilar video pairs, we learn a weight vector applied to the visual word signatures of videos. Using cross-validation, we demonstrate that the learned similarity distance is significantly better correlated with the perceived similarity than the original visual-word-based distance.

Trifocal intraocular lenses: a comparison of the visual performance and quality of vision provided by two different lens designs.

PubMed

Gundersen, Kjell G; Potvin, Rick

2017-01-01

To compare two different diffractive trifocal intraocular lens (IOL) designs, evaluating longer-term refractive outcomes, visual acuity (VA) at various distances, low contrast VA and quality of vision. Patients with binocularly implanted trifocal IOLs of two different designs (FineVision [FV] and Panoptix [PX]) were evaluated 6 months to 2 years after surgery. Best distance-corrected and uncorrected VA were tested at distance (4 m), intermediate (80 and 60 cm) and near (40 cm). A binocular defocus curve was collected with the subject's best distance correction in place. The preferred reading distance was determined along with the VA at that distance. Low contrast VA at distance was also measured. Quality of vision was measured with the National Eye Institute Visual Function Questionnaire near subset and the Quality of Vision questionnaire. Thirty subjects in each group were successfully recruited. The binocular defocus curves differed only at vergences of -1.0 D (FV better, P =0.02), -1.5 and -2.00 D (PX better, P <0.01 for both). Best distance-corrected and uncorrected binocular vision were significantly better for the PX lens at 60 cm ( P <0.01) with no significant differences at other distances. The preferred reading distance was between 42 and 43 cm for both lenses, with the VA at the preferred reading distance slightly better with the PX lens ( P =0.04). There were no statistically significant differences by lens for low contrast VA ( P =0.1) or for quality of vision measures ( P >0.3). Both trifocal lenses provided excellent distance, intermediate and near vision, but several measures indicated that the PX lens provided better intermediate vision at 60 cm. This may be important to users of tablets and other handheld devices. Quality of vision appeared similar between the two lens designs.

Evaluation of physical dimension changes as nondestructive measurements for monitoring rigor mortis development in broiler muscles.

PubMed

Cavitt, L C; Sams, A R

2003-07-01

Studies were conducted to develop a non-destructive method for monitoring the rate of rigor mortis development in poultry and to evaluate the effectiveness of electrical stimulation (ES). In the first study, 36 male broilers in each of two trials were processed at 7 wk of age. After being bled, half of the birds received electrical stimulation (400 to 450 V, 400 to 450 mA, for seven pulses of 2 s on and 1 s off), and the other half were designated as controls. At 0.25 and 1.5 h postmortem (PM), carcasses were evaluated for the angles of the shoulder, elbow, and wing tip and the distance between the elbows. Breast fillets were harvested at 1.5 h PM (after chilling) from all carcasses. Fillet samples were excised and frozen for later measurement of pH and R-value, and the remainder of each fillet was held on ice until 24 h postmortem. Shear value and pH means were significantly lower, but R-value means were higher (P < 0.05) for the ES fillets compared to the controls, suggesting acceleration of rigor mortis by ES. The physical dimensions of the shoulder and elbow changed (P < 0.05) during rigor mortis development and with ES. These results indicate that physical measurements of the wings maybe useful as a nondestructive indicator of rigor development and for monitoring the effectiveness of ES. In the second study, 60 male broilers in each of two trials were processed at 7 wk of age. At 0.25, 1.5, 3.0, and 6.0 h PM, carcasses were evaluated for the distance between the elbows. At each time point, breast fillets were harvested from each carcass. Fillet samples were excised and frozen for later measurement of pH and sacromere length, whereas the remainder of each fillet was held on ice until 24 h PM. Shear value and pH means (P < 0.05) decreased, whereas sarcomere length means (P < 0.05) increased over time, indicating rigor mortis development. Elbow distance decreased (P < 0.05) with rigor development and was correlated (P < 0.01) with shear value (r = 0.2581), sarcomere length (r = -0.3079), and pH (r = 0.6303). These results suggest that elbow distance could be used in conjunction with other detection methods for optically automating measurement of rigor mortis development in broiler carcasses.

Fish with Chips: Tracking Reef Fish Movements to Evaluate Size and Connectivity of Caribbean Marine Protected Areas

PubMed Central

Pittman, Simon J.; Monaco, Mark E.; Friedlander, Alan M.; Legare, Bryan; Nemeth, Richard S.; Kendall, Matthew S.; Poti, Matthew; Clark, Randall D.; Wedding, Lisa M.; Caldow, Chris

2014-01-01

Coral reefs and associated fish populations have experienced rapid decline in the Caribbean region and marine protected areas (MPAs) have been widely implemented to address this decline. The performance of no-take MPAs (i.e., marine reserves) for protecting and rebuilding fish populations is influenced by the movement of animals within and across their boundaries. Very little is known about Caribbean reef fish movements creating a critical knowledge gap that can impede effective MPA design, performance and evaluation. Using miniature implanted acoustic transmitters and a fixed acoustic receiver array, we address three key questions: How far can reef fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of reef fish movements? We show that many reef fishes are capable of traveling far greater distances and in shorter duration than was previously known. Across the Puerto Rican Shelf, more than half of our 163 tagged fish (18 species of 10 families) moved distances greater than 1 km with three fish moving more than 10 km in a single day and a quarter spending time outside of MPAs. We provide direct evidence of ecological connectivity across a network of MPAs, including estimated movements of more than 40 km connecting a nearshore MPA with a shelf-edge spawning aggregation. Most tagged fish showed high fidelity to MPAs, but also spent time outside MPAs, potentially contributing to spillover. Three-quarters of our fish were capable of traveling distances that would take them beyond the protection offered by at least 40–64% of the existing eastern Caribbean MPAs. We recommend that key species movement patterns be used to inform and evaluate MPA functionality and design, particularly size and shape. A re-scaling of our perception of Caribbean reef fish mobility and habitat use is imperative, with important implications for ecology and management effectiveness. PMID:24797815

Side effects of intraoral devices for OSAS treatment.

PubMed

Teixeira, Andressa Otranto de Britto; Andrade, Ana Luiza Ladeia; Almeida, Rhita Cristina da Cunha; Almeida, Marco Antonio de Oliveira

2017-10-14

Intraoral devices have increasingly assumed a key role in the treatment of obstructive sleep apnea syndrome, but there are limitations to their indication and side effects that result from their continuous use, as well as the use of the continuous positive airway pressure device. To evaluate the changes in dental positioning caused by the continuous use of mandibular advancement devices. A prospective longitudinal study with a sample of 15 patients, with evaluation of complete documentation after a mean time of 6.47 months, assessed changes in dental positioning due to the use of the Twin Block oral device for the treatment of patients with apnea. The following variables were evaluated: overjet, overbite, upper and lower intermolar distances, upper and lower intercanine distances, Little's irregularity index and the incisor mandibular plane angle. An intraclass correlation test was performed and a correlation index>0.08 was accepted. After verifying the normal sample distribution (Shapiro-Wilks), a parametric test was used (t test), with a significance level set at 5%. There was a decrease in the values of overjet, overbite and Little's irregularity index, whereas there was an increase in the lower intercanine distance and IMPA values. All these variables are influenced, at different levels, by the forward inclination of the lower incisors, an action that can be expected due to the force applied by the device on the dentition. The other variables did not show statistically significant differences. After a mean time of 6.47 months of use of the mandibular advancement device, there were statistically significant changes in the dental positioning, but they were not clinically relevant. However, it is relevant that this device is commonly in use over long periods of time, making the monitoring of these patients of the utmost importance for the duration of their therapy. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Fish with chips: tracking reef fish movements to evaluate size and connectivity of Caribbean marine protected areas.

PubMed

Pittman, Simon J; Monaco, Mark E; Friedlander, Alan M; Legare, Bryan; Nemeth, Richard S; Kendall, Matthew S; Poti, Matthew; Clark, Randall D; Wedding, Lisa M; Caldow, Chris

2014-01-01

Coral reefs and associated fish populations have experienced rapid decline in the Caribbean region and marine protected areas (MPAs) have been widely implemented to address this decline. The performance of no-take MPAs (i.e., marine reserves) for protecting and rebuilding fish populations is influenced by the movement of animals within and across their boundaries. Very little is known about Caribbean reef fish movements creating a critical knowledge gap that can impede effective MPA design, performance and evaluation. Using miniature implanted acoustic transmitters and a fixed acoustic receiver array, we address three key questions: How far can reef fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of reef fish movements? We show that many reef fishes are capable of traveling far greater distances and in shorter duration than was previously known. Across the Puerto Rican Shelf, more than half of our 163 tagged fish (18 species of 10 families) moved distances greater than 1 km with three fish moving more than 10 km in a single day and a quarter spending time outside of MPAs. We provide direct evidence of ecological connectivity across a network of MPAs, including estimated movements of more than 40 km connecting a nearshore MPA with a shelf-edge spawning aggregation. Most tagged fish showed high fidelity to MPAs, but also spent time outside MPAs, potentially contributing to spillover. Three-quarters of our fish were capable of traveling distances that would take them beyond the protection offered by at least 40-64% of the existing eastern Caribbean MPAs. We recommend that key species movement patterns be used to inform and evaluate MPA functionality and design, particularly size and shape. A re-scaling of our perception of Caribbean reef fish mobility and habitat use is imperative, with important implications for ecology and management effectiveness.

Landscape resistance and habitat combine to provide an optimal model of genetic structure and connectivity at the range margin of a small mammal.

PubMed

Marrotte, R R; Gonzalez, A; Millien, V

2014-08-01

We evaluated the effect of habitat and landscape characteristics on the population genetic structure of the white-footed mouse. We develop a new approach that uses numerical optimization to define a model that combines site differences and landscape resistance to explain the genetic differentiation between mouse populations inhabiting forest patches in southern Québec. We used ecological distance computed from resistance surfaces with Circuitscape to infer the effect of the landscape matrix on gene flow. We calculated site differences using a site index of habitat characteristics. A model that combined site differences and resistance distances explained a high proportion of the variance in genetic differentiation and outperformed models that used geographical distance alone. Urban and agriculture-related land uses were, respectively, the most and the least resistant landscape features influencing gene flow. Our method detected the effect of rivers and highways as highly resistant linear barriers. The density of grass and shrubs on the ground best explained the variation in the site index of habitat characteristics. Our model indicates that movement of white-footed mouse in this region is constrained along routes of low resistance. Our approach can generate models that may improve predictions of future northward range expansion of this small mammal. © 2014 John Wiley & Sons Ltd.

[Descemet's stripping automated endothelial keratoplasty (DEAEK). Systematic review of clinical-effectiveness and safety].

PubMed

Paz-Valiñas, L; de la Fuente-Cid, R; de Rojas-Silva, M V; López-Rodríguez, I; López-García, M

2015-04-01

To conduct a systematic review of the efficacy/effectiveness, safety and cost of Descemet's stripping automated endothelial keratoplasty (DSAEK) technique in patients with corneal endothelial failure. Comprehensive literature search conducted in the main biomedical databases from January-May 2012. Following a critical perusal of the total of 485 abstracts retrieved, 16 case series and one economic evaluation study were included. Corrected distance visual acuity and uncorrected distance visual acuity improved after treatment with DSAEK, attaining values of 0.6 to 0.8 and 0.5 respectively. The degree of post-DSAEK astigmatism was not significant with respect to baseline values. The main complications were graft dislocation-detachment (1.5-23%), primary failure (0-12%) and endothelial rejection (0.8-8.5%). In Fuchs' dystrophy and bullous keratopathy, data on the effectiveness of DSAEK indicate post-intervention improvement in uncorrected and corrected distance visual acuity. Astigmatism arising after DSAEK was not significant. The most significant post-DSAEK complications are linked to the viability of the graft, with the most frequent complications being dislocation-detachment and, to a lesser extent, endothelial rejection. The studies that assess DSAEK are case series, and for the most part retrospective. The quality of this type of studies is both low and limited. Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Integrated remote sensing and visualization (IRSV) system for transportation infrastructure operations and management, phase two, volume 2 : applications of LiDAR technology in structural evaluation under normal traffic operation and post blast loading.

DOT National Transportation Integrated Search

2012-03-01

This report focused on two potential applications of terrestrial LiDAR scans on highway : bridges: 1) vehicle crossing effects measured by3-D, terrestrial LiDAR scans of highway bridges : measuring clearance distance; and 2) bridge post-blast geometr...

Wireless data transmission from inside electromagnetic fields.

PubMed

Huertas, José Ignacio; Barraza, Roberto; Echeverry, Julian Mauricio

2010-01-01

This paper describes analytical and experimental work developed to evaluate the effects of the electromagnetic fields produced by high-voltage lines (400 kV) on wireless data transmission at the 900MHz band. In this work the source of the data transmission is located inside the electromagnetic field and the reception station is located at different distances from the power lines. Different atmospheric conditions are considered.

Google Maps offers a new way to evaluate claudication.

PubMed

Khambati, Husain; Boles, Kim; Jetty, Prasad

2017-05-01

Accurate determination of walking capacity is important for the clinical diagnosis and management plan for patients with peripheral arterial disease. The current "gold standard" of measurement is walking distance on a treadmill. However, treadmill testing is not always reflective of the patient's natural walking conditions, and it may not be fully accessible in every vascular clinic. The objective of this study was to determine whether Google Maps, the readily available GPS-based mapping tool, offers an accurate and accessible method of evaluating walking distances in vascular claudication patients. Patients presenting to the outpatient vascular surgery clinic between November 2013 and April 2014 at the Ottawa Hospital with vasculogenic calf, buttock, and thigh claudication symptoms were identified and prospectively enrolled in our study. Onset of claudication symptoms and maximal walking distance (MWD) were evaluated using four tools: history; Walking Impairment Questionnaire (WIQ), a validated claudication survey; Google Maps distance calculator (patients were asked to report their daily walking routes on the Google Maps-based tool runningmap.com, and walking distances were calculated accordingly); and treadmill testing for onset of symptoms and MWD, recorded in a double-blinded fashion. Fifteen patients were recruited for the study. Determination of walking distances using Google Maps proved to be more accurate than by both clinical history and WIQ, correlating highly with the gold standard of treadmill testing for both claudication onset (r = .805; P < .001) and MWD (r = .928; P < .0001). In addition, distances were generally under-reported on history and WIQ. The Google Maps tool was also efficient, with reporting times averaging below 4 minutes. For vascular claudicants with no other walking limitations, Google Maps is a promising new tool that combines the objective strengths of the treadmill test and incorporates real-world walking environments. It offers an accurate, efficient, inexpensive, and readily accessible way to assess walking distances in patients with peripheral vascular disease. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

High resolution ion chamber array delivery quality assurance for robotic radiosurgery: Commissioning and validation.

PubMed

Blanck, Oliver; Masi, Laura; Chan, Mark K H; Adamczyk, Sebastian; Albrecht, Christian; Damme, Marie-Christin; Loutfi-Krauss, Britta; Alraun, Manfred; Fehr, Roman; Ramm, Ulla; Siebert, Frank-Andre; Stelljes, Tenzin Sonam; Poppinga, Daniela; Poppe, Björn

2016-06-01

High precision radiosurgery demands comprehensive delivery-quality-assurance techniques. The use of a liquid-filled ion-chamber-array for robotic-radiosurgery delivery-quality-assurance was investigated and validated using several test scenarios and routine patient plans. Preliminary evaluation consisted of beam profile validation and analysis of source-detector-distance and beam-incidence-angle response dependence. The delivery-quality-assurance analysis is performed in four steps: (1) Array-to-plan registration, (2) Evaluation with standard Gamma-Index criteria (local-dose-difference⩽2%, distance-to-agreement⩽2mm, pass-rate⩾90%), (3) Dose profile alignment and dose distribution shift until maximum pass-rate is found, and (4) Final evaluation with 1mm distance-to-agreement criterion. Test scenarios consisted of intended phantom misalignments, dose miscalibrations, and undelivered Monitor Units. Preliminary method validation was performed on 55 clinical plans in five institutions. The 1000SRS profile measurements showed sufficient agreement compared with a microDiamond detector for all collimator sizes. The relative response changes can be up to 2.2% per 10cm source-detector-distance change, but remains within 1% for the clinically relevant source-detector-distance range. Planned and measured dose under different beam-incidence-angles showed deviations below 1% for angles between 0° and 80°. Small-intended errors were detected by 1mm distance-to-agreement criterion while 2mm criteria failed to reveal some of these deviations. All analyzed delivery-quality-assurance clinical patient plans were within our tight tolerance criteria. We demonstrated that a high-resolution liquid-filled ion-chamber-array can be suitable for robotic radiosurgery delivery-quality-assurance and that small errors can be detected with tight distance-to-agreement criterion. Further improvement may come from beam specific correction for incidence angle and source-detector-distance response. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Effect of diabetes mellitus on walking distance parameters after supervised exercise therapy for intermittent claudication: A systematic review.

PubMed

Hageman, David; Gommans, Lindy Nm; Scheltinga, Marc Rm; Teijink, Joep Aw

2017-02-01

Some believe that certain patients with intermittent claudication may be unsuitable for supervised exercise therapy (SET), based on the presence of comorbidities and the possibly increased risks. We conducted a systematic review (MEDLINE, EMBASE and CENTRAL) to summarize evidence on the potential influence of diabetes mellitus (DM) on the response to SET. Randomized and nonrandomized studies that investigated the effect of DM on walking distance after SET in patients with IC were included. Considered outcome measures were maximal, pain-free and functional walking distance (MWD, PFWD and FWD). Three articles met the inclusion criteria ( n = 845). In one study, MWD was 111 meters (128%) longer in the non-DM group compared to the DM group after 3 months of follow-up ( p = 0.056). In a second study, the non-DM group demonstrated a significant increase in PFWD (114 meters, p ⩽ 0.05) after 3 months of follow-up, whereas there was no statistically significant increase for the DM group (54 meters). On the contrary, the largest study of this review did not demonstrate any adverse effect of DM on MWD and FWD after SET. In conclusion, the data evaluating the effects of DM on SET were inadequate to determine if DM impairs the exercise response. While trends in the data do not suggest an impairment, they are not conclusive. Practitioners should consider this limitation when making clinical decisions.

Effects of renin-angiotensin-aldosterone system inhibitors on mortality, hospitalization, and diastolic function in patients with HFpEF. A meta-analysis of 13 randomized controlled trials.

PubMed

Zhang, Q; Chen, Y; Liu, Q; Shan, Q

2016-02-01

The purpose of this meta-analysis was to evaluate the effects of renin-angiotensin-aldosterone system (RAAS) inhibitors on mortality, hospitalization, diastolic function, and exercise capacity in heart failure with preserved ejection fraction (HFpEF). Thirteen randomized controlled trials (RCTs), totaling 12,532 patients with HFpEF, were selected. All-cause and cardiovascular mortality, all-cause and heart failure-related hospitalization, diastolic function, and the 6-min walk distance were assessed. The risk ratios (RR) of the dichotomous data, weighted mean difference (WMD) of continuous data, and 95 % confidence intervals (CI) were calculated to assess the effects of RAAS inhibitors. RAAS inhibitors significantly decreased heart failure-related hospitalization (RR 0.89; 95 % CI 0.82-0.97; p = 0.01) and improved the diastolic function, as reflected in a reduced E/e' index (MD -1.38; 95 % CI -2.01 to -0.74; p < 0.0001). However, there were no beneficial effects on all-cause cardiovascular mortality and all-cause hospitalization. Other diastolic parameters had few changes compared with the controls. The 6-min walk distance was not improved by the use of RAAS inhibitors. In patients with HFpEF, RAAS inhibitors decreased heart-failure hospitalization and the E/e' index without affecting mortality, all-cause hospitalization, other diastolic function parameters, and the 6-min walk distance.

The effect of inhomogeneities on the distance to the last scattering surface and the accuracy of the CMB analysis

NASA Astrophysics Data System (ADS)

Bolejko, Krzysztof

2011-02-01

The standard analysis of the CMB data assumes that the distance to the last scattering surface can be calculated using the distance-redshift relation as in the Friedmann model. However, in the inhomogeneous universe, even if langδρrang = 0, the distance relation is not the same as in the unperturbed universe. This can be of serious consequences as a change of distance affects the mapping of CMB temperature fluctuations into the angular power spectrum Cl. In addition, if the change of distance is relatively uniform no new temperature fluctuations are generated. It is therefore a different effect than the lensing or ISW effects which introduce additional CMB anisotropies. This paper shows that the accuracy of the CMB analysis can be impaired by the accuracy of calculation of the distance within the cosmological models. Since this effect has not been fully explored before, to test how the inhomogeneities affect the distance-redshift relation, several methods are examined: the Dyer-Roeder relation, lensing approximation, and non-linear Swiss-Cheese model. In all cases, the distance to the last scattering surface is different than when homogeneity is assumed. The difference can be as low as 1% and as high as 80%. An usual change of the distance is around 20-30%. Since the distance to the last scattering surface is set by the position of the CMB peaks, in order to have a good fit, the distance needs to be adjusted. After correcting the distance, the cosmological parameters change. Therefore, a not properly estimated distance to the last scattering surface can be a major source of systematics. This paper shows that if inhomogeneities are taken into account when calculating the distance then models with positive spatial curvature and with ΩΛ ~ 0.8-0.9 are preferred.

Haplotype diversity in the equine myostatin gene with focus on variants associated with race distance propensity and muscle fiber type proportions

PubMed Central

Petersen, Jessica L; Valberg, Stephanie J; Mickelson, James R; McCue, Molly E

2014-01-01

Summary Two variants in the equine myostatin gene (MSTN), including a T/C SNP substitution in the first intron and a 227-bp SINE insertion in the promoter, are associated with muscle fiber type proportions in the Quarter Horse (QH) and with the prediction of race distance propensity in the Thoroughbred (TB). Genotypes from these loci, along with 18 additional variants surrounding MSTN, were examined in 301 horses of 14 breeds to evaluate haplotype relationships and diversity. The C allele of intron 1 was found in 12 of 14 breeds at a frequency of 0.27; the SINE was observed in five breeds, but common in only the TB and QH (0.73 and 0.48 respectively). Haplotype data suggest the SINE insertion is contemporary to and arose upon a haplotype containing the intron 1 C allele. Gluteal muscle biopsies of TBs showed a significant association of the intron 1 C allele and SINE with a higher proportion of Type 2B and lower proportion of Type 1 fibers. However, in the Belgian horse, in which the SINE is not present, the intron 1 SNP was not associated with fiber type proportions, and evaluation of fiber type proportions across the Belgian, TB and QH breeds shows the significant effect of breed on fiber type proportions is negated when evaluating horses without the SINE variant. These data suggest the SINE, rather than the intron 1 SNP, is driving the observed muscle fiber type characteristics and is the variant targeted by selection for short-distance racing. PMID:25160752

Tethered swimming can be used to evaluate force contribution for short-distance swimming performance.

PubMed

Morouço, Pedro G; Marinho, Daniel A; Keskinen, Kari L; Badillo, Juan J; Marques, Mário C

2014-11-01

The purpose of this study was two-fold: (a) to compare stroke and the physiological responses between maximal tethered and free front crawl swimming and (b) to evaluate the contribution of force exertion for swimming performance over short distances. A total of 34 male swimmers, representing various levels of competitive performance, participated in this study. Each participant was tested in both a 30-second maximal tethered swimming test and a 50-m free swimming test. The tethered force parameters, the swimming speed, stroke (stroke rate [SR]), and the physiological responses (increase in blood lactate concentration [ΔBLa], heart rate, and rate of perceived exertion) were recorded and calculated. The results showed no differences in stroke and the physiological responses between tethered and free swimming, with a high level of agreement for the SR and ΔBLa. A strong correlation was obtained between the maximum impulse of force per stroke and the speed (r = 0.91; p < 0.001). Multiple regression analysis revealed that the maximum impulse and SR in the tethered condition explained 84% of the free swimming performance. The relationship between the swimming speed and maximum force tended to be nonlinear, whereas linear relationships were observed with the maximum impulse. This study demonstrates that tethered swimming does not significantly alter stroke and the physiological responses compared with free swimming, and that the maximum impulse per stroke should be used to evaluate the balance between force and the ability to effectively apply force during sprint swimming. Consequently, coaches can rely on tethered forces to identify strength deficits and improve swimming performance over short distances.

Effect of corticosteroids on orthodontic tooth movement in a rabbit model.

PubMed

Abtahi, M; Shafaee, H; Saghravania, N; Peel, S; Giddon, D; Sohrabi, K

2014-01-01

While there are a growing number of studies on the effects of medications on orthodontic tooth movement (OTM), only few studies have investigated the role of corticosteroids, despite their widespread use. The aim of the current study was to evaluate the effects of triamcinolone acetonide injection on OTM in a rabbit model. Sixteen one-month old rabbits were randomly divided into two groups: Eight rabbits had triamcinolone acetonide (1 mg/kg/day) administered IM daily for 21 days (test group) while the remaining eight rabbits received no drug (control group). The rabbits in both groups had a tube bonded to the upper central incisors and a stainless steel helical spring was inserted in tube slot to apply 50 cN distal force. After 3 weeks, the rabbits were sacrificed and the distance between mesial corners of incisors was measured The incisors are associated tissue was processed for histology and the apical and cervical area of the roots evaluated. An observer who was blind to the study groups evaluated the specimens. All appliance-treated incisors in test and control groups showed evidence of tooth movement. The distance between the incisors was significantly greater in the triamcinolone acetonide treated group compared to the control group (P < 0.001). Histological examination revealed an increased number of resorption lacunae and decreased number of cuboidal osteoblastic cells around the apical and cervical area of the Incisor roots in the test compared to the control group (P < 0.01). Treatment with triamcinolone acetonide is associated with increased tooth movement in rabbits via increased resorptive activity in the alveolar bone.

Evaluation of three different methods of distance learning for postgraduate diagnostic imaging education: A pilot study.

PubMed

Poirier, Jean-Nicolas; Cooley, Jeffrey R; Wessely, Michelle; Guebert, Gary M; Petrocco-Napuli, Kristina

2014-10-01

Objective : The purpose of this study was to evaluate the perceived effectiveness and learning potential of 3 Web-based educational methods in a postgraduate radiology setting. Methods : Three chiropractic radiology faculty from diverse geographic locations led mini-courses using asynchronous discussion boards, synchronous Web conferencing, and asynchronous voice-over case presentations formatted for Web viewing. At the conclusion of each course, participants filled out a 14-question survey (using a 5-point Likert scale) designed to evaluate the effectiveness of each method in achieving specified course objectives and goals and their satisfaction when considering the learning potential of each method. The mean, standard deviation, and percentage agreements were tabulated. Results : Twenty, 15, and 10 participants completed the discussion board, Web conferencing, and case presentation surveys, respectively. All educational methods demonstrated a high level of agreement regarding the course objective (total mean rating >4.1). The case presentations had the highest overall rating for achieving the course goals; however, all but one method still had total mean ratings >4.0 and overall agreement levels of 70%-100%. The strongest potential for interactive learning was found with Web conferencing and discussion boards, while case presentations rated very low in this regard. Conclusions : The perceived effectiveness in achieving the course objective and goals was high for each method. Residency-based distance education may be a beneficial adjunct to current methods of training, allowing for international collaboration. When considering all aspects tested, there does not appear to be a clear advantage to any one method. Utilizing various methods may be most appropriate.

Teaching basic medical sciences at a distance: strategies for effective teaching and learning in internet-based courses.

PubMed

Ertmer, Peggy A; Nour, Abdelfattah Y M

2007-01-01

In recent years, the Internet has become an effective and accessible delivery mechanism for distance education. In 2003, 81% of all institutions of higher education offered at least one fully online or hybrid course. By 2005, the proportion of institutions that listed online education as important to their long-term goals had increased by 8%. This growth in available online courses and their increased convenience and flexibility have stimulated dramatic increases in enrollment in online programs, including the Veterinary Technology Distance Learning Program (VT-DLP) at Purdue University. Regardless of the obvious benefits, distance learning (DL) can be frustrating for the learners if course developers are unable to merge their knowledge about the learners, the process of instructional design, and the appropriate uses of technology and interactivity options into effective course designs. This article describes strategies that we have used to increase students' learning of physiology content in an online environment. While some of these are similar, if not identical, to strategies that might be used in a face-to-face (f2f) environment (e.g., case studies, videos, concept maps), additional strategies (e.g., animations, virtual microscopy) are needed to replace or supplement what might normally occur in a f2f course. We describe how we have addressed students' need for instructional interaction, specifically in the context of two foundational physiology courses that occur early in the VT-DLP. Although the teaching and learning strategies we have used have led to increasingly high levels of interaction, there is an ongoing need to evaluate these strategies to determine their impact on students' learning of physiology content, their development of problem-solving skills, and their retention of information.

Assessment of Location and Anatomical Characteristics of Mental Foramen, Anterior Loop and Mandibular Incisive Canal Using Cone Beam Computed Tomography.

PubMed

Panjnoush, Mehrdad; Rabiee, Zonnar Sadat; Kheirandish, Yasaman

2016-03-01

This study aimed to evaluate the location and characteristics of mental foramen, anterior loop and mandibular incisive canal using cone beam computed tomography (CBCT). This retrospective cross-sectional study evaluated 200 mandibular CBCT scans for the location of mental foramen, anterior loop prevalence and mandibular incisive canal visibility, its mean length and distance to buccal and lingual plates and inferior border of the mandible. The effect of age and gender on these variables was also analyzed (P<0.05). Anterior loop and mandibular incisive canal were seen in 59.5% and 97.5% of the cases, respectively. The mean length of the mandibular incisive canal was 10.48±4.53mm in the right and 10.40±4.52mm in the left side. The mean distance from the endpoints of the canal to buccal plate was 3.63±1.73mm in the right and 3.66±1.45mm in the left side. These distances were 3.89±1.53mm in the right and 4.13±1.48mm in the left side to lingual plate and 9.98±2.07mm in the right and 8.62±1.97mm in the left side to the inferior border of the mandible. The distance from the endpoints of the canal to lingual plate was significantly different in the right and left sides. The distance from the endpoint of the canal to the buccal plate and inferior border of the mandible was significantly shorter in females (P=0.016), and had a weak, significant correlation with age (rsp=0.215, P=0.003). Due to variability in mandibular incisive canal length and high prevalence of anterior loop, CBCT is recommended before surgical manipulation of interforaminal region.

MP2, DFT-D, and PCM study of the HMB-TCNE complex: Thermodynamics, electric properties, and solvent effects

NASA Astrophysics Data System (ADS)

Kysel, Ondrej; Budzák, Scaronimon; Medveď, Miroslav; Mach, Pavel

Geometry, thermodynamic, and electric properties of the pi-EDA complex between hexamethylbenzene (HMB) and tetracyanoethylene (TCNE) are investigated at the MP2/6-31G* and, partly, DFT-D/6-31G* levels. Solvent effects on the properties are evaluated using the PCM model. Fully optimized HMB-TCNE geometry in gas phase is a stacking complex with an interplanar distance 2.87 × 10-10 m and the corresponding BSSE corrected interaction energy is -51.3 kJ mol-1. As expected, the interplanar distance is much shorter in comparison with HF and DFT results. However the crystal structures of both (HMB)2-TCNE and HMB-TCNE complexes have interplanar distances somewhat larger (3.18 and 3.28 × 10-10 m, respectively) than our MP2 gas phase value. Our estimate of the distance in CCl4 on the basis of PCM solvent effect study is also larger (3.06-3.16 × 10-10 m). The calculated enthalpy, entropy, Gibbs energy, and equilibrium constant of HMB-TCNE complex formation in gas phase are: DeltaH0 = -61.59 kJ mol-1, DeltaSc0 = -143 J mol-1 K-1, DeltaG0 = -18.97 kJ mol-1, and K = 2,100 dm3 mol-1. Experimental data, however, measured in CCl4 are significantly lower: DeltaH0 = -34 kJ mol-1, DeltaSc0 = -70.4 J mol-1 K-1, DeltaG0 = -13.01 kJ mol-1, and K = 190 dm3 mol-1. The differences are caused by solvation effects which stabilize more the isolated components than the complex. The total solvent destabilization of Gibbs energy of the complex relatively to that of components is equal to 5.9 kJ mol-1 which is very close to our PCM value 6.5 kJ mol-1. MP2/6-31G* dipole moment and polarizabilities are in reasonable agreement with experiment (3.56 D versus 2.8 D for dipole moment). The difference here is due to solvent effect which enlarges interplanar distance and thus decreases dipole moment value. The MP2/6-31G* study supplemented by DFT-D parameterization for enthalpy calculation, and by the PCM approach to include solvent effect seems to be proper tools to elucidate the properties of pi-EDA complexes.

Development of Intra-knee Joint Sustained-Release Gel Formulation and Evaluation of Its Pharmacological Efficiency in Rats.

PubMed

Noda, Takehiro; Okuda, Tomoyuki; Ban, Kousuke; Mizuno, Ryota; Tagami, Tatsuaki; Ozeki, Tetsuya; Okamoto, Hirokazu

2017-06-01

In the development of a drug for intra-articular administration, a sustained-release formulation is desirable since it is difficult to sustain the effects of conventional injections due to fast drug leakage from the joint cavity. In this study, we prepared sustained release gel formulations for intra-articular administration containing indocyanine green (ICG) as a model drug to follow its fate after intra-articular administration in rats with in-vivo imaging system (IVIS). ICG administered as an aqueous solution leaked from the joint cavity in a short time and was excreted out of the body within a day. On the other hand, ICG in the sustained-release formulations was retained and released in the joint cavity for a week. Next, we prepared a sustained-release formulation with hyaluronic acid (HA) as the gel base containing a pain-relief drug (Drug A). We had administered it and other formulations into the rat knee where we injected bradykinin to evaluate their walking distance after 1 and 3 d. The effect of an aqueous solution of Drug A disappeared on day 3. The HA gel formulation without Drug A was more effective than the aqueous solution. The HA gel formulation with Drug A was the most effective; the walking distance was about 85% of the baseline on day 3. This study showed that the gel formulations were effective to sustain the release of a drug in the knee joint, and that the combination of a pain-relief drug with HA gel was effective to improve the mobility of the acute pain model rats.

Dalfampridine Effects Beyond Walking Speed in Multiple Sclerosis

PubMed Central

Fjeldstad, Cecilie; Suárez, Gustavo; Klingler, Michael; Henney, Herbert R.; Rabinowicz, Adrian L.

2015-01-01

Background: Dalfampridine extended release (ER) improves walking in people with multiple sclerosis (MS), as demonstrated by walking speed improvement. This exploratory study evaluated treatment effects of dalfampridine-ER on gait, balance, and walking through treatment withdrawal and reinitiation. Methods: Dalfampridine-ER responders, based on Timed 25-Foot Walk (T25FW) assessment before study entry, were included in this open-label, three-period, single-center study. Period 1: on-drug evaluations performed at screening and 1 week after screening. Period 2: dalfampridine-ER withdrawal and off-drug evaluations (days 5 and 11). Period 3: dalfampridine-ER reinitiation/final on-drug evaluation (day 15). Primary outcome variables: NeuroCom composite scores for gait and balance; balance was evaluated if gait changes were significant. Secondary variables: individual NeuroCom scores, walking speed (T25FW) and distance (2-Minute Walk Test [2MWT]), and balance (Berg Balance Scale [BBS]). Results: All 20 patients completed the study: mean age, 53.1 years; mean MS duration, 11.3 years; mean time taking dalfampridine-ER, 315.3 days. NeuroCom gait composite scores worsened during period 2 relative to period 1 and improved during period 3; the mean ± SD difference in gait composite scores on drug was 4.03 ± 1.51 points (P = .015). Balance composite scores did not change significantly. Improvements were observed for off-drug versus on-drug for T25FW (0.36 ft/sec, P < .001), 2MWT (25.4 ft, P = .006), and BBS (1.7 points, P = .003). Safety profile was consistent with previous studies. Conclusions: Significant improvements in gait, walking speed, distance, and balance were demonstrated by dalfampridine-ER reinitiation after a 10-day withdrawal period. PMID:26664333

Un modelo para el control de calidad academica de los textos de instruccion a distancia (A Model for Controlling the Academic Quality of Distance Education Texts).

ERIC Educational Resources Information Center

Bolanos-Mora, Guiselle; And Others

1992-01-01

In response to the need for a system of control over the academic quality of distance education texts, this article proposes a methodological model based on criteria that evaluate written materials based on their instructional quality, design, and production. A discussion and figures evaluate educational aspects of content, communication,…

Less precise representation of numerical magnitude in high math-anxious individuals: an ERP study of the size and distance effects.

PubMed

Núñez-Peña, M Isabel; Suárez-Pellicioni, Macarena

2014-12-01

Numerical comparison tasks are widely used to study the mental representation of numerical magnitude. In study, event-related brain potentials (ERPs) were recorded while 26 high math-anxious (HMA) and 27 low math-anxious (LMA) individuals were presented with pairs of single-digit Arabic numbers and were asked to decide which one had the larger numerical magnitude. The size of the numbers and the distance between them were manipulated in order to study the size and the distance effects. The results showed that both distance and size effects were larger for the HMA group. As for ERPs, results showed that the ERP distance effect had larger amplitude for both the size and distance effects in the HMA group than among their LMA counterparts. Since this component has been taken as a marker of the processing of numerical magnitude, this result suggests that HMA individuals have a less precise representation of numerical magnitude. Copyright © 2014 Elsevier B.V. All rights reserved.

Visual Inspection of Surfaces

NASA Technical Reports Server (NTRS)

Hughes, David; Perez, Xavier

2007-01-01

This presentation evaluates the parameters that affect visual inspection of cleanliness. Factors tested include surface reflectance, surface roughness, size of the largest particle, exposure time, inspector and distance from sample surface. It is concluded that distance predictions were not great, particularly because the distance at which contamination is seen may depend on more variables than those tested. Most parameters estimates had confidence of 95% or better, except for exposure and reflectance. Additionally, the distance at which surface is visibly contaminated decreases with increasing reflectance, roughness, and exposure. The distance at which the surface is visually contaminated increased with the largest particle size. These variables were only slightly affected the observer.

Integrated methods for teaching population health.

PubMed

Sistrom, Maria Gilson; Zeigen, Laura; Jones, Melissa; Durham, Korana Fiol; Boudrot, Thomas

2011-01-01

The Institute of Medicine recommends reforms to public health education to better prepare the public health workforce. This study addresses the application of two of the recommended reforms in the population health nursing curriculum at one university: use of an ecological model and distance learning methods. Using interdisciplinary faculty, integrated teaching and learning methods, and a multimedia curriculum, this study examined the following question: can distance learning be designed to support learning goals and outcomes specific to an ecological approach and population health concepts in general? Course content was evaluated using students' perception of practice utility and understanding of population health concepts. Integrated teaching methods were evaluated using a scale as well as comparison to other student distance learning experiences within the university. Findings demonstrated that both the ecological model and distance learning methods were successfully used to teach population health to a large nursing student cohort. 2011, SLACK Incorporated.

The evaluation of alternate methodologies for land cover classification in an urbanizing area

NASA Technical Reports Server (NTRS)

Smekofski, R. M.

1981-01-01

The usefulness of LANDSAT in classifying land cover and in identifying and classifying land use change was investigated using an urbanizing area as the study area. The question of what was the best technique for classification was the primary focus of the study. The many computer-assisted techniques available to analyze LANDSAT data were evaluated. Techniques of statistical training (polygons from CRT, unsupervised clustering, polygons from digitizer and binary masks) were tested with minimum distance to the mean, maximum likelihood and canonical analysis with minimum distance to the mean classifiers. The twelve output images were compared to photointerpreted samples, ground verified samples and a current land use data base. Results indicate that for a reconnaissance inventory, the unsupervised training with canonical analysis-minimum distance classifier is the most efficient. If more detailed ground truth and ground verification is available, the polygons from the digitizer training with the canonical analysis minimum distance is more accurate.

An Overview and Empirical Comparison of Distance Metric Learning Methods.

PubMed

Moutafis, Panagiotis; Leng, Mengjun; Kakadiaris, Ioannis A

2016-02-16

In this paper, we first offer an overview of advances in the field of distance metric learning. Then, we empirically compare selected methods using a common experimental protocol. The number of distance metric learning algorithms proposed keeps growing due to their effectiveness and wide application. However, existing surveys are either outdated or they focus only on a few methods. As a result, there is an increasing need to summarize the obtained knowledge in a concise, yet informative manner. Moreover, existing surveys do not conduct comprehensive experimental comparisons. On the other hand, individual distance metric learning papers compare the performance of the proposed approach with only a few related methods and under different settings. This highlights the need for an experimental evaluation using a common and challenging protocol. To this end, we conduct face verification experiments, as this task poses significant challenges due to varying conditions during data acquisition. In addition, face verification is a natural application for distance metric learning because the encountered challenge is to define a distance function that: 1) accurately expresses the notion of similarity for verification; 2) is robust to noisy data; 3) generalizes well to unseen subjects; and 4) scales well with the dimensionality and number of training samples. In particular, we utilize well-tested features to assess the performance of selected methods following the experimental protocol of the state-of-the-art database labeled faces in the wild. A summary of the results is presented along with a discussion of the insights obtained and lessons learned by employing the corresponding algorithms.

Hip abductor strength and lower extremity running related injury in distance runners: A systematic review.

PubMed

Mucha, Matthew D; Caldwell, Wade; Schlueter, Emily L; Walters, Carly; Hassen, Amy

2017-04-01

Determine the association between hip abduction strength and lower extremity running related injury in distance runners. Systematic review. Prospective longitudinal and cross sectional studies that quantified hip abduction strength and provided diagnosis of running related injury in distance runners were included and assessed for quality. Effect size was calculated for between group differences in hip abduction strength. Of the 1841 articles returned in the initial search, 11 studies matched all inclusion criteria. Studies were grouped according to injury: iliotibial band syndrome, patellofemoral pain syndrome, medial tibial stress syndrome, tibial stress fracture, and Achilles tendinopathy, and examined for strength differences between injured and non-injured groups. Meaningful differences were found in the studies examining iliotibial band syndrome. Three of five iliotibial band syndrome articles found weakness in runners with iliotibial band syndrome; two were of strong methodological rigor and both of those found a relationship between weakness and injury. Other results did not form associative or predictive relationships between weakness and injury in distance runners. Hip abduction weakness evaluated by hand held dynamometer may be associated with iliotibial band syndrome in distance runners as suggested by several cross sectional studies but is unclear as a significant factor for the development of patellofemoral pain syndrome, medial tibial stress syndrome, tibial stress fracture or Achilles tendinopathy according to the current literature. Future studies are needed with consistent methodology and inclusion of all distance running populations to determine the significance of hip abduction strength in relationship to lower extremity injury. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Modelling the distance impedance of protest attendance

NASA Astrophysics Data System (ADS)

Traag, V. A.; Quax, R.; Sloot, P. M. A.

2017-02-01

Protesters are usually young, relatively well educated, middle class people that are politically engaged. But where do protesters come from? We here show, based on mobile phone data, that distance is an important impedance to protest attendance. Most protesters come from nearby regions, suggesting distance forms an obstacle to participation. Although this effect can be partly explained by social network effects, which show similar spatial dependencies, an effect of distance remains. This suggests distance still acts as an obstacle to participation, although it may also be that long-range contacts are less effective for recruitment. Face-to-face contacts seem more important in spreading protests through earlier participants, whereas central recruitment works better by telephone. Our results are important for understanding processes of recruitment.

Auditory distance perception in humans: a review of cues, development, neuronal bases, and effects of sensory loss.

PubMed

Kolarik, Andrew J; Moore, Brian C J; Zahorik, Pavel; Cirstea, Silvia; Pardhan, Shahina

2016-02-01

Auditory distance perception plays a major role in spatial awareness, enabling location of objects and avoidance of obstacles in the environment. However, it remains under-researched relative to studies of the directional aspect of sound localization. This review focuses on the following four aspects of auditory distance perception: cue processing, development, consequences of visual and auditory loss, and neurological bases. The several auditory distance cues vary in their effective ranges in peripersonal and extrapersonal space. The primary cues are sound level, reverberation, and frequency. Nonperceptual factors, including the importance of the auditory event to the listener, also can affect perceived distance. Basic internal representations of auditory distance emerge at approximately 6 months of age in humans. Although visual information plays an important role in calibrating auditory space, sensorimotor contingencies can be used for calibration when vision is unavailable. Blind individuals often manifest supranormal abilities to judge relative distance but show a deficit in absolute distance judgments. Following hearing loss, the use of auditory level as a distance cue remains robust, while the reverberation cue becomes less effective. Previous studies have not found evidence that hearing-aid processing affects perceived auditory distance. Studies investigating the brain areas involved in processing different acoustic distance cues are described. Finally, suggestions are given for further research on auditory distance perception, including broader investigation of how background noise and multiple sound sources affect perceived auditory distance for those with sensory loss.

A guide to the use of distance sampling to estimate abundance of Karner blue butterflies

USGS Publications Warehouse

Grundel, Ralph

2015-01-01

This guide is intended to describe the use of distance sampling as a method for evaluating the abundance of Karner blue butterflies at a location. Other methods for evaluating abundance exist, including mark-release-recapture and index counts derived from Pollard-Yates surveys, for example. Although this guide is not intended to be a detailed comparison of the pros and cons of each type of method, there are important preliminary considerations to think about before selecting any method for evaluating the abundance of Karner blue butterflies.

Collaborative Evaluation within a Framework of Stakeholder-Oriented Evaluation Approaches

ERIC Educational Resources Information Center

O'Sullivan, Rita G.

2012-01-01

Collaborative Evaluation systematically invites and engages stakeholders in program evaluation planning and implementation. Unlike "distanced" evaluation approaches, which reject stakeholder participation as evaluation team members, Collaborative Evaluation assumes that active, on-going engagement between evaluators and program staff,…

Evaluating the Implementation of the Online Tutorial for the Universitas Terbuka Distance Learning Bachelor Degree Program in Indonesia

ERIC Educational Resources Information Center

Zubaidah, Ida

2013-01-01

Universitas Terbuka (UT), the Indonesia Open University and the 45th state university in the country, is the only one that uses distance learning as its sole mode of delivery and instruction. Although UT has operated for 28 years, unlike face-to-face classroom-based education, distance education has not been considered as a fully legitimate…

Guidance on the Use of Learning Strategies in Distance Education (DE) as a Function of Age and Gender

ERIC Educational Resources Information Center

Alliprandini, Paula Mariza Zedu; Pavesi, Marilza Aparecida; Dayanne, Vicentini; Sekitani, Juliane Tiemi

2015-01-01

This study aims to determine whether there are differences in the use of learning strategies used by students enrolled in courses offered in the format of Distance Learning (DL) by gender and age of participants. A total of 402 students responded to a range of learning strategies evaluations-version adapted for distance learning, containing 49…

Technology Options for Multimedia in Distance Learning. A Report for the Commission of the European Communities--Task Force Human Resources, Education, Training, and Youth.

ERIC Educational Resources Information Center

Sherwood-Roberts, P.; Vervest, P.

This report focuses on interactive multimedia delivery platforms available for distance education. An introduction addresses the role of distance education and open learning in covering training needs and advantages of interactive multimedia in training. Chapter 2 proposes a multimedia skills evaluation framework and examines the elements of this…

The effect of debris-flow composition on runout distance

NASA Astrophysics Data System (ADS)

de Haas, Tjalling; Braat, Lisanne; Leuven, Jasper; Lokhorst, Ivar; Kleinhans, Maarten

2015-04-01

Estimating runout distance is of major importance for the assessment and mitigation of debris-flow hazards. Debris-flow runout distance depends on debris-flow composition and topography, but state-of-the-art runout prediction methods are mainly based on topographical parameters and debris-flow volume, while composition is generally neglected or incorporated in empirical constants. Here we experimentally investigated the effect of debris-flow composition and topography on runout distance. We created the first small-scale experimental debris flows with self-formed levees, distinct lobes and morphology and texture accurately resembling natural debris flows. In general, the effect of debris-flow composition on runout distance was larger than the effect of topography. Enhancing channel slope and width, outflow plain slope, debris-flow size and water fraction leads to an increase in runout distance. However, runout distance shows an optimum relation with coarse-material and clay fraction. An increase in coarse-material fraction leads to larger runout distances by increased grain collisional forces and more effective levee formation, but too much coarse debris causes a large accumulation of coarse debris at the flow front, enhancing friction and decreasing runout. An increase in clay fraction initially enlarges the volume and viscosity of the interstitial fluid, liquefying the flow and enhancing runout, while a further increase leads to very viscous flows with high yield strength, reducing runout. These results highlight the importance and further need of research on the relation between debris-flow composition and runout distance. Our experiments further provide valuable insight on the effects of debris-flow composition on depositional mechanisms and deposit morphology.

Geographic distance affects dispersal of the patchy distributed greater long-tailed hamster (Tscherskia triton).

PubMed

Xue, Huiliang; Zhong, Min; Xu, Jinhui; Xu, Laixiang

2014-01-01

Dispersal is a fundamental process in ecology influencing the genetic structure and the viability of populations. Understanding how variable factors influence the dispersal of the population is becoming an important question in animal ecology. To date, geographic distance and geographic barriers are often considered as main factors impacting dispersal, but their effects are variable depending on different conditions. In general, geographic barriers affect more significantly than geographic distance on dispersal. In rapidly expanding populations, however, geographic barriers have less effect on dispersal than geographic distance. The effects of both geographic distance and geographic barriers in low-density populations with patchy distributions are poorly understood. By using a panel of 10 microsatellite loci we investigated the genetic structure of three patchy-distributed populations of the Greater long-tailed hamster (Tscherskia triton) from Raoyang, Guan and Shunyi counties of the North China Plain. The results showed that (i) high genetic diversity and differentiation exist in three geographic populations with patchy distributions; (ii) gene flow occurs among these three populations with physical barriers of Beijing city and Hutuo River, which potentially restricted the dispersal of the animal; (iii) the gene flow is negatively correlated with the geographic distance, while the genetic distance shows the positive correlation. Our results suggest that the effect of the physical barriers is conditional-dependent, including barrier capacity or individual potentially dispersal ability. Geographic distance also acts as an important factor affecting dispersal for the patchy distributed geographic populations. So, gene flow is effective, even at relatively long distances, in balancing the effect of geographic barrier in this study.

Programmable shunts and headphones: Are they safe together?

PubMed

Spader, Heather S; Ratanaprasatporn, Linda; Morrison, John F; Grossberg, Jonathan A; Cosgrove, G Rees

2015-10-01

Programmable shunts have a valuable role in the treatment of patients with hydrocephalus, but because a magnet is used to change valve settings, interactions with external magnets may reprogram these shunts. Previous studies have demonstrated the ability of magnetic toys and iPads to erroneously reprogram shunts. Headphones are even more ubiquitous, and they contain an electromagnet for sound projection that sits on the head very close to the shunt valve. This study is the first to look at the magnetic field emissions of headphones and their effect on reprogrammable shunt valves to ascertain whether headphones are safe for patients with these shunts to wear. In this in vitro study of the magnetic properties of headphones and their interactions with 3 different programmable shunts, the authors evaluated Apple earbuds, Beats by Dr. Dre, and Bose QuietComfort Acoustic Noise Cancelling headphones. Each headphone was tested for electromagnetic field emissions using a direct current gaussmeter. The following valves were evaluated: Codman Hakim programmable valve, Medtronic Strata II valve, and Aesculap proGAV. Each valve was tested at distances of 0 to 50 mm (in 5-mm increments) from each headphone. The exposure time at each distance was 1 minute, and 3 trials were performed to confirm results at each valve setting and distance. All 3 headphones generated magnetic fields greater than the respective shunt manufacturer's recommended strength of exposure, but these fields did not persist beyond 5 mm. By 2 cm, the fields levels were below 20 G, well below the Medtronic recommendation of 90 G and the Codman recommendation of 80 G. Because the mechanism for the proGAV is different, there is no recommended gauss level. There was no change in gauss-level emissions by the headphones with changes in frequency and amplitude. Both the Strata and Codman-Hakim valves were reprogrammed by direct contact (distance 0 mm) with the Bose headphones. When a rotation component was added, all 3 headphones reprogrammed the Strata and Codman-Hakim valves at 0 mm. At all distances above 0 mm, the headphones did not affect the shunts. The proGAV valve was not affected by headphones at any distance. Although all the headphones studied generated significant gauss fields at distances less than 5 mm, the programmable valve settings only changed at a distance of 0 mm (i.e., with direct contact). Given the subcutaneous location of the valve, the authors conclude that is highly unlikely that commercially available or customary headphones can contribute to the reprogramming of shunts.

Analysis of speed, stroke rate, and stroke distance for world-class breaststroke swimming.

PubMed

Garland Fritzdorf, Stephen; Hibbs, Angela; Kleshnev, Valery

2009-02-15

Speed in aquatic locomotion is determined by stroke distance and stroke rate, but it does not always follow that an increase in stroke rate will lead to an increase in speed. Kleshnev (2006) developed a method to evaluate the relationship between speed and stroke rate during rowing - the effective work per stroke. In this case study, the effective work per stroke was determined for a male world-class 100-m breaststroke swimmer for seven races in major championships and compared between: each of the seven races; each quarter within each race; and the best swims of this case study and seven other world-class swimmers. The effective work per stroke was related to race performance, with the fastest race having the highest effective work per stroke and lowest stroke rate, with slower races having low effectiveness and high stroke rate (R(2) = 0.85). The effective work per stroke was reduced in a race as the swimmer fatigued. The within-race standard deviation of effectiveness was lower in fast swims (R(2) = 0.84). This analysis has identified some characteristics of fast swimming: high effectiveness, optimal stroke rate, and a flat effectiveness profile. Training and racing strategies can now be devised to improve performance by increasing the sensitivity of assessment of strengths and weaknesses in individuals.

Development of a distance-to-roadway proximity metric to compare near-road pollutant levels to a central site monitor

NASA Astrophysics Data System (ADS)

Barzyk, Timothy M.; George, Barbara Jane; Vette, Alan F.; Williams, Ronald W.; Croghan, Carry W.; Stevens, Carvin D.

The primary objective of the Detroit Exposure and Aerosol Research Study (DEARS) was to compare air pollutant concentrations measured at various neighborhoods, or exposure monitoring areas (EMAs), throughout a major metropolitan area to levels measured at a central site or community monitor. One of the EMAs was located near a busy freeway (annual average daily traffic (AADT) of ˜130,000) so that impacts of mobile sources could be examined. Air pollution concentrations from the roadway-proximate sites were compared to the central site monitor. The volatile organic compounds (VOCs) selected (benzene, toluene, ethylbenzene, m,p- and o-xylene, 1,3 butadiene, 1,3,5-trimethylbenzene and 4-ethyltoluene) are typically associated with mobile sources. Gradients were also evident that demonstrated the amplification of pollutant levels near the roadway compared to the community monitor. A novel distance-to-roadway proximity metric was developed to plot the measurements and model these gradients. Effective distance represents the actual distance an air parcel travels from the middle of a roadway to a site and varies as a function of wind direction, whereas perpendicular distance is a fixed distance oriented normal to the roadway. Perpendicular distance is often used as a proxy for exposures to traffic emissions in epidemiological studies. Elevated concentrations of all the compounds were found for both a summer and winter season. Effective distance was found to be a statistically significant ( p < 0.05) univariate predictor for concentrations of toluene, ethylbenzene, m,p-xylene and o-xylene for summer 2005. For each of these pollutants, effective distance yielded lower p-values than the corresponding perpendicular distance models, and model fit improved. Results demonstrate that this near-road EMA had elevated levels of traffic-related VOCs compared to the community monitor, and that effective distance was a more accurate predictor of the degree to which they were elevated as a function of distance. Effective distance produced a range of distance-to-roadway values for a single site based on wind direction, thus increasing the number and range of values that could be used to plot and predict relative differences in pollutant concentrations between two sites.

The effect of distance to provider on employee response to changes in mental health benefits.

PubMed

Lindrooth, Richard C; Lo Sasso, Anthony T; Lurie, Ithai Z

2006-10-01

We assess whether distance to provider moderates the effect of a change in mental health benefits on treatment initiation of employees of a large US-based company for psychiatric disorders. Mental health treatment administrative claims data plus eligibility information provided by a Fortune 50 company for the years 1995-1998 are used for the analysis. The effect of distance is measured using the relative effect of the initiative on residents living far from providers compared to those living close to providers. We model the probability of treatment initiation using a random effects logit specification. We find that the effect of distance to provider has the potential to over-shadow other incentives to initiate treatment, especially at distances greater than 4 miles. These results lend further support to the notion that geographic dispersion of providers should be an important consideration when forming a selective contracting network. Copyright (c) 2006 John Wiley & Sons, Ltd.

Evaluation of viewing experiences induced by curved 3D display

NASA Astrophysics Data System (ADS)

Mun, Sungchul; Park, Min-Chul; Yano, Sumio

2015-05-01

As advanced display technology has been developed, much attention has been given to flexible panels. On top of that, with the momentum of the 3D era, stereoscopic 3D technique has been combined with the curved displays. However, despite the increased needs for 3D function in the curved displays, comparisons between curved and flat panel displays with 3D views have rarely been tested. Most of the previous studies have investigated their basic ergonomic aspects such as viewing posture and distance with only 2D views. It has generally been known that curved displays are more effective in enhancing involvement in specific content stories because field of views and distance from the eyes of viewers to both edges of the screen are more natural in curved displays than in flat panel ones. For flat panel displays, ocular torsions may occur when viewers try to move their eyes from the center to the edges of the screen to continuously capture rapidly moving 3D objects. This is due in part to differences in viewing distances from the center of the screen to eyes of viewers and from the edges of the screen to the eyes. Thus, this study compared S3D viewing experiences induced by a curved display with those of a flat panel display by evaluating significant subjective and objective measures.

Evaluating and comparing methods of sinkhole susceptibility mapping in the Ebro Valley evaporite karst (NE Spain)

NASA Astrophysics Data System (ADS)

Galve, J. P.; Gutiérrez, F.; Remondo, J.; Bonachea, J.; Lucha, P.; Cendrero, A.

2009-10-01

Multiple sinkhole susceptibility models have been generated in three study areas of the Ebro Valley evaporite karst (NE Spain) applying different methods (nearest neighbour distance, sinkhole density, heuristic scoring system and probabilistic analysis) for each sinkhole type separately (cover collapse sinkholes, cover and bedrock collapse sinkholes and cover and bedrock sagging sinkholes). The quantitative and independent evaluation of the predictive capability of the models reveals that: (1) The most reliable susceptibility models are those derived from the nearest neighbour distance and sinkhole density. These models can be generated in a simple and rapid way from detailed geomorphological maps. (2) The reliability of the nearest neighbour distance and density models is conditioned by the degree of clustering of the sinkholes. Consequently, the karst areas in which sinkholes show a higher clustering are a priori more favourable for predicting new occurrences. (3) The predictive capability of the best models obtained in this research is significantly higher (12.5-82.5%) than that of the heuristic sinkhole susceptibility model incorporated into the General Urban Plan for the municipality of Zaragoza. Although the probabilistic approach provides lower quality results than the methods based on sinkhole proximity and density, it helps to identify the most significant factors and select the most effective mitigation strategies and may be applied to model susceptibility in different future scenarios.

The Sound of Success: Investigating Cognitive and Behavioral Effects of Motivational Music in Sports

PubMed Central

Elvers, Paul; Steffens, Jochen

2017-01-01

Listening to music before, during, or after sports is a common phenomenon, yet its functions and effects on performance, cognition, and behavior remain to be investigated. In this study we present a novel approach to the role of music in sports and exercise that focuses on the notion of musical self-enhancement (Elvers, 2016). We derived the following hypotheses from this framework: listening to motivational music will (i) enhance self-evaluative cognition, (ii) improve performance in a ball game, and (iii) evoke greater risk-taking behavior. To evaluate the hypotheses, we conducted a between-groups experiment (N = 150) testing the effectiveness of both an experimenter playlist and a participant-selected playlist in comparison to a no-music control condition. All participants performed a ball-throwing task developed by Decharms and Davé (1965), consisting of two parts: First, participants threw the ball from fixed distances into a funnel basket. During this task, performance was measured. In the second part, the participants themselves chose distances from the basket, which allowed their risk-taking behavior to be assessed. The results indicate that listening to motivational music led to greater risk taking but did not improve ball-throwing performance. This effect was more pronounced in male participants and among those who listened to their own playlists. Furthermore, self-selected music enhanced state self-esteem in participants who were performing well but not in those who were performing poorly. We also discuss further implications for the notion of musical self-enhancement. PMID:29209257

Leader-team congruence in power distance values and team effectiveness: the mediating role of procedural justice climate.

PubMed

Cole, Michael S; Carter, Min Z; Zhang, Zhen

2013-11-01

We examine the effect of (in)congruence between leaders' and teams' power distance values on team effectiveness. We hypothesize that the (in)congruence between these values would differentially predict team effectiveness, with procedural justice climate serving as a mediator. Using multisource data and polynomial regression, we found that similarities (and differences) between leaders' and their teams' power distance values can have consequential effects on teams' justice climate and, ultimately, their effectiveness (viz., team performance and team organizational citizenship behavior). We conclude that to fully understand the implications of power distance, one should consider the multiple perspectives of both leaders and team members. (c) 2013 APA, all rights reserved.

Effect of 1. 5 tesla nuclear magnetic resonance imaging scanner on implanted permanent pacemakers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayes, D.L.; Holmes, D.R. Jr.; Gray, J.E.

1987-10-01

Patients with a permanent pacemaker are currently restricted from diagnostic nuclear magnetic resonance (NMR) imaging because of potential adverse effects on the pacemaker by the magnet. Previous work has shown that NMR imaging will result in asynchronous pacing of the pulse generator within a given distance of the magnet. The radiofrequency signal generated by the system may also result in rapid cardiac pacing, which may have deleterious effects. This study utilized a 1.5 tesla unit in an in vivo laboratory animal to evaluate the unit's effects on eight different pulse generators from two manufacturers. All pacemakers functioned in an asynchronousmore » mode when placed within a certain distance of the magnet. In addition, transient reed switch inhibition was observed. Seven of the eight pulse generators paced rapidly when exposed to the radiofrequency signal and there was a dramatic decrease in arterial blood pressure. Whether effective rapid cardiac pacing would occur could not be predicted before exposure to the magnetic resonance unit. Nuclear magnetic resonance imaging with high magnetic fields in patients with a pacemaker should continue to be avoided until the mechanism of the rapid cardiac pacing can be further delineated and either predicted or prevented.« less

Facet Joint Osteoarthritis Affects Spinal Segmental Motion in Degenerative Spondylolisthesis.

PubMed

Kitanaka, Shigeyuki; Takatori, Ryota; Arai, Yuji; Nagae, Masateru; Tonomura, Hitoshi; Mikami, Yasuo; Inoue, Nozomu; Ogura, Taku; Fujiwara, Hiroyoshi; Kubo, Toshikazu

2018-06-15

This is a retrospective clinical case series (case-control study). To clarify the influence of facet joint osteoarthritis (FJOA) on the pathology of degenerative spondylolisthesis (DS) using in vivo 3-dimensional image analysis. There are no radical treatments to prevent progression of DS in patients with lumbar spinal canal stenosis associated with DS. Therefore, an effective treatment method based on the pathology of DS should be developed. In total, 50 patients with lumbar spinal canal stenosis involving L4/5 who underwent dynamic computed tomography were divided into 2 groups: with DS [spondylolisthesis (Sp) group; 12 male, 14 female; mean age, 74 y]; and without DS (non-Sp group; 15 male, 9 female; mean age, 70 y). Degeneration of the intervertebral disk and FJOA at L4/5 were evaluated using magnetic resonance imaging. Disk and intervertebral foramen heights, the distance between the craniocaudal edges of the facet joint, and the interspinous distance were measured on dynamic computed tomographic images. Also, in vivo 3-dimensional segmental motion was evaluated using the volume merge method. There were no significant differences in degenerative findings for the intervertebral disk; however, progressive FJOA was detected in the Sp group. Dynamic changes in the distance between the craniocaudal edges of the facet joints were significantly larger in the Sp group. In this study, progressive FJOA and larger segmental motion in the distance between the craniocaudal edges of the facet joints were found in the Sp group. We clarified for the first time that DS involves ligament laxity due to FJOA that affects spinal segmental motion in vivo. We consider that a treatment method based on FJOA would be useful for treating patients with DS. Level IV.

Is the transposition of the nipple-areolar complex necessary in Simon grade 2b gynecomastia operations using suction-assisted liposuction?

PubMed

Özalp, Burhan; Berköz, Ömer; Aydınol, Mustafa

2018-02-01

The aim of this study was to assess the efficacy of suction-assisted liposuction (SAL) in Simon grade 2b gynecomastia and its effect on sternal notch to nipple areola (SNN) distance. A retrospective analysis was performed on 21 patients with grade 2b gynecomastia who underwent SAL. Preoperative and postoperative SNN distances of the patients were measured, the results were analysed using a Mann-Whitney U test and a p-value <.05 was accepted as statistically significant. Aesthetic results were evaluated by the surgical team considering five criteria: breast size, breast shape, nipple-areolar complex positioning, scarring, and skin tightness of the breast envelope. A 10-point Likert scale was used to assess patient satisfaction with SAL surgery. All of the patients were followed up for an average period of 17.8 months (range = 12-28 months). The mean amount of lipoaspirate was 232 mL per breast (range = 190-310 mL). The mean preoperative SNN distance was 22.3 cm (range = 20-23.5 cm), whereas postoperative was 21.3 cm (range = 19.2-22.8 cm); the difference was statistically significant (p < .05). There was one case of nipple areola necrosis, three hypoesthesia, five persistent pains, and four slight buttonhole deformities. The aesthetic result was evaluated as very good by the surgical team, and the overall patient satisfaction rate in terms of breast shape and volume was 92%. It was concluded that SAL provides a good aesthetic outcome in patients with Simon grade 2b gynecomastia and shortens the SNN distance by 1 cm, but further clinical studies are required to support this conclusion.

Performance analysis of jump-gliding locomotion for miniature robotics.

PubMed

Vidyasagar, A; Zufferey, Jean-Christohphe; Floreano, Dario; Kovač, M

2015-03-26

Recent work suggests that jumping locomotion in combination with a gliding phase can be used as an effective mobility principle in robotics. Compared to pure jumping without a gliding phase, the potential benefits of hybrid jump-gliding locomotion includes the ability to extend the distance travelled and reduce the potentially damaging impact forces upon landing. This publication evaluates the performance of jump-gliding locomotion and provides models for the analysis of the relevant dynamics of flight. It also defines a jump-gliding envelope that encompasses the range that can be achieved with jump-gliding robots and that can be used to evaluate the performance and improvement potential of jump-gliding robots. We present first a planar dynamic model and then a simplified closed form model, which allow for quantification of the distance travelled and the impact energy on landing. In order to validate the prediction of these models, we validate the model with experiments using a novel jump-gliding robot, named the 'EPFL jump-glider'. It has a mass of 16.5 g and is able to perform jumps from elevated positions, perform steered gliding flight, land safely and traverse on the ground by repetitive jumping. The experiments indicate that the developed jump-gliding model fits very well with the measured flight data using the EPFL jump-glider, confirming the benefits of jump-gliding locomotion to mobile robotics. The jump-glide envelope considerations indicate that the EPFL jump-glider, when traversing from a 2 m height, reaches 74.3% of optimal jump-gliding distance compared to pure jumping without a gliding phase which only reaches 33.4% of the optimal jump-gliding distance. Methods of further improving flight performance based on the models and inspiration from biological systems are presented providing mechanical design pathways to future jump-gliding robot designs.

Copper link evaluations/solutions for fiber channel, SSA, SONET, ATM, and other services through 4 Gb/sec: basic information, test results, and evaluation

NASA Astrophysics Data System (ADS)

Leib, Michael J.

1995-10-01

Technitrol, the original designer of MIL-STD-1553 transformers, the original military 1Mb/s LAN, has advanced the state of the art one further notch, introducing a series of transceivers that allow high speed (through 1 Gb/s) data transmission over copper wire instead of fiber optic cable. One such device can be employed to implement the Fiber Channel Interface as defined by hte X3T11 ANSI Fibre Channel Committee using either mini coax, Type 1 shielded twisted pair, twinax or video cable. The technology now exists to upgrade data transmission rates on current physical media to speeds formerly only available with fiber optic cabling. Copper transceiver technology provides a cost effective alternative for dealing with demanding high speed applications such as high speed serial data transfer, high speed disk and tape storage transfer, imaging telemetry, radar, and other avionics applications. Eye diagrams will be presented to show that excellent data transmission at rates of 1 gigabit/sec with low jitter is capable over mini coax at distances to approximately 50 meters, shielded twisted pair and twinax cable to distances of 105 meters, and video cable to distances of 175 meters. Distances are further at lower data rates. As a member of the X3T11 ANSI Fiber Channel Committee, Technitrol has developed a Physical Media (copper wire) Dependant (PMD) transceiver not only compliant with the Fibre Channel Specifications but exceeding the specifications by a factor greater than four. Conceivably, this opens high speed interconnections for today's high data rate requirements to copper cabling systems. Fibre Optic problems need not be dealt with to obtain data transfers for high speed information transfers.

Validation of stereophotogrammetry of the human torso.

PubMed

Lee, Juhun; Kawale, Manas; Merchant, Fatima A; Weston, June; Fingeret, Michelle C; Ladewig, Dianne; Reece, Gregory P; Crosby, Melissa A; Beahm, Elisabeth K; Markey, Mia K

2011-02-15

The objective of this study was to determine if measurements of breast morphology computed from three-dimensional (3D) stereophotogrammetry are equivalent to traditional anthropometric measurements obtained directly on a subject using a tape measure. 3D torso images of 23 women ranged in age from 36 to 63 who underwent or were scheduled for breast reconstruction surgery were obtained using a 3dMD torso system (3Q Technologies Inc., Atlanta, GA). Two different types (contoured and line-of-sight distances) of a total of nine distances were computed from 3D images of each participant. Each participant was photographed twice, first without fiducial points marked (referred to as unmarked image) and second with fiducial points marked prior to imaging (referred to as marked image). Stereophotogrammetry was compared to traditional direct anthropometry, in which measurements were taken with a tape measure on participants. Three statistical analyses were used to evaluate the agreement between stereophotogrammetry and direct anthropometry. Seven out of nine distances showed excellent agreement between stereophotogrammetry and direct anthropometry (both marked and unmarked images). In addition, stereophotogrammetry from the unmarked image was equivalent to that of the marked image (both line-of-sight and contoured distances). A lower level of agreement was observed for some measures because of difficulty in localizing more vaguely defined fiducial points, such as lowest visible point of breast mound, and inability of the imaging system in capturing areas obscured by the breast, such as the inframammary fold. Stereophotogrammetry from 3D images obtained from the 3dMD torso system is effective for quantifying breast morphology. Tools for surgical planning and evaluation based on stereophotogrammetry have the potential to improve breast surgery outcomes.

Comparative absorption, electroabsorption and electrochemical studies of intervalence electron transfer and electronic coupling in cyanide-bridged bimetallic systems: ancillary ligand effects

NASA Astrophysics Data System (ADS)

Vance, Fredrick W.; Slone, Robert V.; Stern, Charlotte L.; Hupp, Joseph T.

2000-03-01

Electroabsorption or Stark spectroscopy has been used to evaluate the systems (NC) 5M II-CN-Ru III(NH 3) 51- and (NC) 5M II-CN-Ru III(NH 3) 4py 1-, where M II=Fe II or Ru II. When a pyridine ligand is present in the axial position on the Ru III acceptor, the effective optical electron transfer distance - as measured by the change in dipole moment, |Δ μ| - is increased by more than 35% relative to the ammine substituted counterpart. Comparison of the charge transfer distances to the crystal structure of Na[(CN) 5Fe-CN-Ru(NH 3) 4py] · 6H 2O reveals that the Stark derived distances are ˜50% to ˜90% of the geometric separation of the metal centers. The differences result in an upward revision in the Hush delocalization parameter, c b2, and of the electronic coupling matrix element, H ab, relative to those parameters obtained exclusively from electronic absorption measurements. The revised parameters are compared to those, which are obtained via electrochemical techniques and found to be in only fair agreement. We conclude that the absorption/electroabsorption analysis likely yields a more reliable set of mixing and coupling parameters.

Objective assessment of the effect of pupil size upon the power distribution of multifocal contact lenses.

PubMed

Papadatou, Eleni; Del Águila-Carrasco, Antonio J; Esteve-Taboada, José J; Madrid-Costa, David; Cerviño-Expósito, Alejandro

2017-01-01

To analytically assess the effect of pupil size upon the refractive power distributions of different designs of multifocal contact lenses. Two multifocal contact lenses of center-near design and one multifocal contact lens of center-distance design were used in this study. Their power profiles were measured using the NIMO TR1504 device (LAMBDA-X, Belgium). Based on their power profiles, the power distribution was assessed as a function of pupil size. For the high addition lenses, the resulting refractive power as a function of viewing distance (far, intermediate, and near) and pupil size was also analyzed. The power distribution of the lenses was affected by pupil size differently. One of the lenses showed a significant spread in refractive power distribution, from about -3 D to 0 D. Generally, the power distribution of the lenses expanded as the pupil diameter became greater. The surface of the lens dedicated for each distance varied substantially with the design of the lens. In an experimental basis, our results show how the lenses power distribution is affected by the pupil size and underlined the necessity of careful evaluation of the patient's visual needs and the optical properties of a multifocal contact lens for achieving the optimal visual outcome.

A methodology for improving the spatial framework for secondary education: An example from trinidad and tobago

NASA Astrophysics Data System (ADS)

London, Norrel A.

1992-03-01

Following a period of massive quantitative increases in education provision in the 1970's and 1980's, many Third World nations now find it difficult to provide additional school places to improve their present system of education provision. Strapped by financial constraints on the one hand, and on the other by pressing demands for efficient and effective services, developing nations have been encouraged to adopt judicious and careful spatial planning as a way out of the present dilemma. The paper uses a technical model to demonstrate how Trinidad and Tobago may reduce the problem of a lengthy journey-to-school, currently faced by many secondary school students. Paradoxically, this results from the Government's efforts to expand the system of secondary education during the past two decades. Using an index of distance travelled between home and school, the paper evaluates the geographic location of eight schools that have been proposed for construction by Trinidad and Tobago, and recommends alternative locations that would more effectively and more quickly achieve the Government's objective of minimizing home-to-school distances now travelled by secondary students. The rank order in which the proposed eight schools ought to be built, so as to achieve distance minimization with incremental addition of each new facility is also suggested.

Method and Application for Dynamic Comprehensive Evaluation with Subjective and Objective Information

PubMed Central

Liu, Dinglin; Zhao, Xianglian

2013-01-01

In an effort to deal with more complicated evaluation situations, scientists have focused their efforts on dynamic comprehensive evaluation research. How to make full use of the subjective and objective information has become one of the noteworthy content. In this paper, a dynamic comprehensive evaluation method with subjective and objective information is proposed. We use the combination weighting method to determine the index weight. Analysis hierarchy process method is applied to dispose the subjective information, and criteria importance through intercriteria correlation method is used to handle the objective information. And for the time weight determination, we consider both time distance and information size to embody the principle of esteeming the present over the past. And then the linear weighted average model is constructed to make the evaluation process more practicable. Finally, an example is presented to illustrate the effectiveness of this method. Overall, the results suggest that the proposed method is reasonable and effective. PMID:24386176

Representing connectivity: quantifying effective habitat availability based on area and connectivity for conservation status assessment and recovery.

PubMed

Neel, Maile; Tumas, Hayley R; Marsden, Brittany W

2014-01-01

We apply a comprehensive suite of graph theoretic metrics to illustrate how landscape connectivity can be effectively incorporated into conservation status assessments and in setting conservation objectives. These metrics allow conservation practitioners to evaluate and quantify connectivity in terms of representation, resiliency, and redundancy and the approach can be applied in spite of incomplete knowledge of species-specific biology and dispersal processes. We demonstrate utility of the graph metrics by evaluating changes in distribution and connectivity that would result from implementing two conservation plans for three endangered plant species (Erigeron parishii, Acanthoscyphus parishii var. goodmaniana, and Eriogonum ovalifolium var. vineum) relative to connectivity under current conditions. Although distributions of the species differ from one another in terms of extent and specific location of occupied patches within the study landscape, the spatial scale of potential connectivity in existing networks were strikingly similar for Erigeron and Eriogonum, but differed for Acanthoscyphus. Specifically, patches of the first two species were more regularly distributed whereas subsets of patches of Acanthoscyphus were clustered into more isolated components. Reserves based on US Fish and Wildlife Service critical habitat designation would not greatly contribute to maintain connectivity; they include 83-91% of the extant occurrences and >92% of the aerial extent of each species. Effective connectivity remains within 10% of that in the whole network for all species. A Forest Service habitat management strategy excluded up to 40% of the occupied habitat of each species resulting in both range reductions and loss of occurrences from the central portions of each species' distribution. Overall effective network connectivity was reduced to 62-74% of the full networks. The distance at which each CHMS network first became fully connected was reduced relative to the full network in Erigeron and Acanthoscyphus due to exclusion of peripheral patches, but was slightly increased for Eriogonum. Distances at which networks were sensitive to loss of connectivity due to presence non-redundant connections were affected mostly for Acanthoscyphos. Of most concern was that the range of distances at which lack of redundancy yielded high risk was much greater than in the full network. Through this in-depth example evaluating connectivity using a comprehensive suite of developed graph theoretic metrics, we establish an approach as well as provide sample interpretations of subtle variations in connectivity that conservation managers can incorporate into planning.

Representing connectivity: quantifying effective habitat availability based on area and connectivity for conservation status assessment and recovery

PubMed Central

Tumas, Hayley R.; Marsden, Brittany W.

2014-01-01

We apply a comprehensive suite of graph theoretic metrics to illustrate how landscape connectivity can be effectively incorporated into conservation status assessments and in setting conservation objectives. These metrics allow conservation practitioners to evaluate and quantify connectivity in terms of representation, resiliency, and redundancy and the approach can be applied in spite of incomplete knowledge of species-specific biology and dispersal processes. We demonstrate utility of the graph metrics by evaluating changes in distribution and connectivity that would result from implementing two conservation plans for three endangered plant species (Erigeron parishii, Acanthoscyphus parishii var. goodmaniana, and Eriogonum ovalifolium var. vineum) relative to connectivity under current conditions. Although distributions of the species differ from one another in terms of extent and specific location of occupied patches within the study landscape, the spatial scale of potential connectivity in existing networks were strikingly similar for Erigeron and Eriogonum, but differed for Acanthoscyphus. Specifically, patches of the first two species were more regularly distributed whereas subsets of patches of Acanthoscyphus were clustered into more isolated components. Reserves based on US Fish and Wildlife Service critical habitat designation would not greatly contribute to maintain connectivity; they include 83–91% of the extant occurrences and >92% of the aerial extent of each species. Effective connectivity remains within 10% of that in the whole network for all species. A Forest Service habitat management strategy excluded up to 40% of the occupied habitat of each species resulting in both range reductions and loss of occurrences from the central portions of each species’ distribution. Overall effective network connectivity was reduced to 62–74% of the full networks. The distance at which each CHMS network first became fully connected was reduced relative to the full network in Erigeron and Acanthoscyphus due to exclusion of peripheral patches, but was slightly increased for Eriogonum. Distances at which networks were sensitive to loss of connectivity due to presence non-redundant connections were affected mostly for Acanthoscyphos. Of most concern was that the range of distances at which lack of redundancy yielded high risk was much greater than in the full network. Through this in-depth example evaluating connectivity using a comprehensive suite of developed graph theoretic metrics, we establish an approach as well as provide sample interpretations of subtle variations in connectivity that conservation managers can incorporate into planning. PMID:25320685

Action at an Attentional Distance: A Study of Children's Reasoning about Causes and Effects Involving Spatial and Attentional Discontinuity

ERIC Educational Resources Information Center

Grotzer, Tina A.; Solis, S. Lynneth

2015-01-01

Spatial discontinuity between causes and effects is a feature of many scientific concepts, particularly those in the environmental and ecological sciences. Causes can be spatially separated from their effects by great distances. Action at a distance, the idea that causes and effects can be separated in physical space, is a well-studied concept in…

Socioeconomic position and low birth weight among mothers exposed to traffic-related air pollution.

PubMed

Habermann, Mateus; Gouveia, Nelson

2014-01-01

Atmospheric pollution is a major public health concern. It can affect placental function and restricts fetal growth. However, scientific knowledge remains too limited to make inferences regarding causal associations between maternal exposure to air pollution and adverse effects on pregnancy. This study evaluated the association between low birth weight (LBW) and maternal exposure during pregnancy to traffic related air pollutants (TRAP) in São Paulo, Brazil. Analysis included 5,772 cases of term-LBW (<2,500 g) and 5,814 controls matched by sex and month of birth selected from the birth registration system. Mothers' addresses were geocoded to estimate exposure according to 3 indicators: distance from home to heavy traffic roads, distance-weighted traffic density (DWTD) and levels of particulate matter ≤10 µg/m3 estimated through land use regression (LUR-PM10). Final models were evaluated using multiple logistic regression adjusting for birth, maternal and pregnancy characteristics. We found decreased odds in the risk of LBW associated with DWTD and LUR-PM10 in the highest quartiles of exposure with a significant linear trend of decrease in risk. The analysis with distance from heavy traffic roads was less consistent. It was also observed that mothers with higher education and neighborhood-level income were potentially more exposed to TRAP. This study found an unexpected decreased risk of LBW associated with traffic related air pollution. Mothers with advantaged socioeconomic position (SEP) although residing in areas of higher vehicular traffic might not in fact be more expose to air pollution. It can also be that the protection against LBW arising from a better SEP is stronger than the effect of exposure to air pollution, and this exposure may not be sufficient to increase the risk of LBW for these mothers.

Beat-the-wave evacuation mapping for tsunami hazards in Seaside, Oregon, USA

USGS Publications Warehouse

Priest, George R.; Stimely, Laura; Wood, Nathan J.; Madin, Ian; Watzig, Rudie

2016-01-01

Previous pedestrian evacuation modeling for tsunamis has not considered variable wave arrival times or critical junctures (e.g., bridges), nor does it effectively communicate multiple evacuee travel speeds. We summarize an approach that identifies evacuation corridors, recognizes variable wave arrival times, and produces a map of minimum pedestrian travel speeds to reach safety, termed a “beat-the-wave” (BTW) evacuation analysis. We demonstrate the improved approach by evaluating difficulty of pedestrian evacuation of Seaside, Oregon, for a local tsunami generated by a Cascadia subduction zone earthquake. We establish evacuation paths by calculating the least cost distance (LCD) to safety for every grid cell in a tsunami-hazard zone using geospatial, anisotropic path distance algorithms. Minimum BTW speed to safety on LCD paths is calculated for every grid cell by dividing surface distance from that cell to safety by the tsunami arrival time at safety. We evaluated three scenarios of evacuation difficulty: (1) all bridges are intact with a 5-minute evacuation delay from the start of earthquake, (2) only retrofitted bridges are considered intact with a 5-minute delay, and (3) only retrofitted bridges are considered intact with a 10-minute delay. BTW maps also take into account critical evacuation points along complex shorelines (e.g., peninsulas, bridges over shore-parallel estuaries) where evacuees could be caught by tsunami waves. The BTW map is able to communicate multiple pedestrian travel speeds, which are typically visualized by multiple maps with current LCD-based mapping practices. Results demonstrate that evacuation of Seaside is problematic seaward of the shore-parallel waterways for those with any limitations on mobility. Tsunami vertical-evacuation refuges or additional pedestrian bridges may be effective ways of reducing loss of life seaward of these waterways.

Socioeconomic Position and Low Birth Weight among Mothers Exposed to Traffic-Related Air Pollution

PubMed Central

Habermann, Mateus; Gouveia, Nelson

2014-01-01

Background Atmospheric pollution is a major public health concern. It can affect placental function and restricts fetal growth. However, scientific knowledge remains too limited to make inferences regarding causal associations between maternal exposure to air pollution and adverse effects on pregnancy. This study evaluated the association between low birth weight (LBW) and maternal exposure during pregnancy to traffic related air pollutants (TRAP) in São Paulo, Brazil. Methods and findings Analysis included 5,772 cases of term-LBW (<2,500 g) and 5,814 controls matched by sex and month of birth selected from the birth registration system. Mothers’ addresses were geocoded to estimate exposure according to 3 indicators: distance from home to heavy traffic roads, distance-weighted traffic density (DWTD) and levels of particulate matter ≤10 µg/m3 estimated through land use regression (LUR-PM10). Final models were evaluated using multiple logistic regression adjusting for birth, maternal and pregnancy characteristics. We found decreased odds in the risk of LBW associated with DWTD and LUR-PM10 in the highest quartiles of exposure with a significant linear trend of decrease in risk. The analysis with distance from heavy traffic roads was less consistent. It was also observed that mothers with higher education and neighborhood-level income were potentially more exposed to TRAP. Conclusions This study found an unexpected decreased risk of LBW associated with traffic related air pollution. Mothers with advantaged socioeconomic position (SEP) although residing in areas of higher vehicular traffic might not in fact be more expose to air pollution. It can also be that the protection against LBW arising from a better SEP is stronger than the effect of exposure to air pollution, and this exposure may not be sufficient to increase the risk of LBW for these mothers. PMID:25426640

Optical design and evaluation of a 4 mm cost-effective ultra-high-definition arthroscope.

PubMed

Cheng, Dewen; Wang, Yongtian; Yu, Lu; Liu, Xiaohua

2014-08-01

High definition and magnification rigid endoscope plays an important role in modern minimally invasive medical surgery and diagnosis. In this paper, we present the design and evaluation methods of a high definition rigid endoscope, specifically an arthroscope, with a large depth of field (DOF). The incident heights and exit angles of the sampled rays on the relay lens are controlled during the optimization process to ensure an effective field view (70°) and a normal ray path within the limited lens diameter of 2.7 mm. The lens is set up as a multi-configuration system with two extreme and one middle object distances to cover a large DOF. As a result, an entrance pupil of 0.3 mm is achieved for the first time, to bring the theoretical resolution to 23.1 lps/mm in the object space at a working distance of 20 mm, with the wavelength of 0.532 um. The modulation transfer function (MTF) curves approach diffraction limit, and the values are all higher than 0.3 at 160 line pairs/mm (lps/mm) in the image space. Meanwhile, stray light caused by total internal reflection on the inner wall of the rod lenses and the objective lens is eliminated. The measured resolution in the object space at a 20 mm working distance is 22.3 lps/mm, and test results show that other performance characteristics also fulfill design requirements. The relay lenses are designed with only one type of the spacer and two types of lenses to greatly reduce the fabrication and assembly cost. The design method has important research and application values for lens systems used in modern minimally invasive medical surgery and industrial non-destructive testing area.

Pulley Ruptures in Rock Climbers: Outcome of Conservative Treatment With the Pulley-Protection Splint-A Series of 47 Cases.

PubMed

Schneeberger, Micha; Schweizer, Andreas

2016-06-01

To evaluate the effectiveness of conservative treatment of finger flexor tendon pulley rupture with a pulley-protection splint (PPS) with regard to reduction in tendon-phalanx distance (TPD) and functional and sport-specific outcomes in a retrospective case series. Tendon-phalanx distance in active forced flexion was measured before and after treatment in ultrasound records. Functional and sport-specific outcomes were evaluated by means of a questionnaire, which also contained instructions for self-measurement of finger range of motion and finger strength. Forty-seven complete pulley ruptures in 45 rock climbers (mean age, 33.4 years; range, 21.8-56.2 years) were included in the study. In the 39 patients who had follow-up ultrasound examination, PPS treatment decreased mean ± SD TPD from 4.4 ± 1.0 mm to 2.3 ± 0.6 mm after A2 pulley rupture and from 2.9 ± 0.7 mm to 2.1 ± 0.5 mm after A4 pulley rupture. Tendon-phalanx distance was reduced in all patients. Finger range of motion (n = 42) and finger strength (n = 22) did not differ significantly between treated and contralateral sides. Of the 43 climbers who completed questionnaires, 38 had regained their previous climbing level a mean 8.8 months after pulley rupture; 1 reported reduced finger dexterity; 39 assessed their treatment results to be good, and 4 to be very good. The PPS is an effective conservative treatment modality for pulley ruptures, which reduces TPD and enables the patient to regain previous finger function. Copyright © 2016 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

Biometry of the hypospadic penis after hormone therapy (testosterone and estrogen): A randomized, double-blind controlled trial.

PubMed

Paiva, Kelly Christina de Castro; Bastos, André Netto; Miana, Laura Pimenta; Barros, Eveline de Souza; Ramos, Plínio Santos; Miranda, Lara Meneguelli; Faria, Natália Maia; Avarese de Figueiredo, André; de Bessa, José; Netto, José Murillo B

2016-08-01

The use of preoperative hormonal stimulation before hypospadias surgery aims to increase penile size and achieve better surgical results; however, the rules are not clear in the literature. We evaluated the effects of topical testosterone and estrogen in the hypospadic penis regarding biometric measures, side effects, and serum hormonal levels. To our knowledge, this is the first study using estradiol prior to hypospadias surgery. Sixty-nine children with hypospadias were randomly divided into three study groups: a control group (CG) of 17 children given placebo cream; a testosterone group (TG) of 28 children who used 1% testosterone propionate; and an estradiol group (EG) of 24 children using 0.01% estradiol. All subjects applied the topical ointment on the entire penis, twice daily for 30 days before surgical correction. Biometric evaluation of the penis included penile length and diameter, glans diameter, distance from the urethral meatus to the tip, and the width of the urethral plate. These measurements as well as serum hormone level, and side effects were evaluated prior to hormone use, and 30 and 90 days after. After 30 days an increase in penile diameter and length and diameter of the glans were observed in TG (p < 0.05). The width of the urethral plate and distance from meatus to the tip increased in TG, although not significantly. The most frequent side effects were appearance of pubic hair and darkening of the genital skin, mainly in TG, but these were transient and disappeared after 90 days of treatment. No significant variations were seen in serum hormonal levels (Table). As in previous studies, an increase in penile length and diameter, and glans diameter was observed with the use of testosterone. Proximal urethral plate width and distance from the meatus to the tip of the penis had a tendency to increase also in TG. Estradiol did not change biometric measure of the penis. Few side effects occurred after both hormones, and any that did improved after 90 days follow-up and did not change hormone serum levels. Preoperative use of topical testosterone increases penile size, diameter of the penis and glans. The use of estradiol does not change penile biometry. Side effects occur mainly with the use of testosterone and are transient. No significant and persistent hormonal changes were observed. Copyright © 2016 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Evaluating Alerting and Guidance Performance of a UAS Detect-And-Avoid System

NASA Technical Reports Server (NTRS)

Lee, Seung Man; Park, Chunki; Thipphavong, David P.; Isaacson, Douglas R.; Santiago, Confesor

2016-01-01

A key challenge to the routine, safe operation of unmanned aircraft systems (UAS) is the development of detect-and-avoid (DAA) systems to aid the UAS pilot in remaining "well clear" of nearby aircraft. The goal of this study is to investigate the effect of alerting criteria and pilot response delay on the safety and performance of UAS DAA systems in the context of routine civil UAS operations in the National Airspace System (NAS). A NAS-wide fast-time simulation study was conducted to assess UAS DAA system performance with a large number of encounters and a broad set of DAA alerting and guidance system parameters. Three attributes of the DAA system were controlled as independent variables in the study to conduct trade-off analyses: UAS trajectory prediction method (dead-reckoning vs. intent-based), alerting time threshold (related to predicted time to LoWC), and alerting distance threshold (related to predicted Horizontal Miss Distance, or HMD). A set of metrics, such as the percentage of true positive, false positive, and missed alerts, based on signal detection theory and analysis methods utilizing the Receiver Operating Characteristic (ROC) curves were proposed to evaluate the safety and performance of DAA alerting and guidance systems and aid development of DAA system performance standards. The effect of pilot response delay on the performance of DAA systems was evaluated using a DAA alerting and guidance model and a pilot model developed to support this study. A total of 18 fast-time simulations were conducted with nine different DAA alerting threshold settings and two different trajectory prediction methods, using recorded radar traffic from current Visual Flight Rules (VFR) operations, and supplemented with DAA-equipped UAS traffic based on mission profiles modeling future UAS operations. Results indicate DAA alerting distance threshold has a greater effect on DAA system performance than DAA alerting time threshold or ownship trajectory prediction method. Further analysis on the alert lead time (time in advance of predicted loss of well clear at which a DAA alert is first issued) indicated a strong positive correlation between alert lead time and DAA system performance (i.e. the ability of the UAS pilot to maneuver the unmanned aircraft to remain well clear). While bigger distance thresholds had beneficial effects on alert lead time and missed alert rate, it also generated a higher rate of false alerts. In the design and development of DAA alerting and guidance systems, therefore, the positive and negative effects of false alerts and missed alerts should be carefully considered to achieve acceptable alerting system performance by balancing false and missed alerts. The results and methodology presented in this study are expected to help stakeholders, policymakers and standards committees define the appropriate setting of DAA system parameter thresholds for UAS that ensure safety while minimizing operational impacts to the NAS and equipage requirements for its users before DAA operational performance standards can be finalized.

Geography and distance effect on financial dynamics in the Chinese stock market

NASA Astrophysics Data System (ADS)

Li, Xing; Qiu, Tian; Chen, Guang; Zhong, Li-Xin; Jiang, Xiong-Fei

2016-09-01

Geography effect is investigated for the Chinese stock market including the Shanghai and Shenzhen stock markets, based on the daily data of individual stocks. The stocks in the Shanghai city and the Guangdong province are found to greatly contribute to the Shanghai and Shenzhen markets in the geographical sector, respectively. By investigating a geographical correlation on a geographical parameter, the stock location is found to have an impact on the financial dynamics, except for the financial crisis time of the Shenzhen market. Stock distance effect is further studied, with the probability of the short distance observed to be much greater than that of the long distance. The distance is found to only affect the stock correlation of the Shanghai stock market, but has no effect on the Shenzhen stock market.

A New Distance Metric for Unsupervised Learning of Categorical Data.

PubMed

Jia, Hong; Cheung, Yiu-Ming; Liu, Jiming

2016-05-01

Distance metric is the basis of many learning algorithms, and its effectiveness usually has a significant influence on the learning results. In general, measuring distance for numerical data is a tractable task, but it could be a nontrivial problem for categorical data sets. This paper, therefore, presents a new distance metric for categorical data based on the characteristics of categorical values. In particular, the distance between two values from one attribute measured by this metric is determined by both the frequency probabilities of these two values and the values of other attributes that have high interdependence with the calculated one. Dynamic attribute weight is further designed to adjust the contribution of each attribute-distance to the distance between the whole data objects. Promising experimental results on different real data sets have shown the effectiveness of the proposed distance metric.

The Northwest's Hot Topics in Preparedness forum: a novel distance-learning collaborative.

PubMed

Shield, Margaret; Wiesner, Paul; Curran, Connie; Stark, Greg; Rauch, Steve; Stergachis, Andy; Thompson, Jack

2005-11-01

The Northwest Center for Public Health Practice at the University of Washington hosts a training forum, called Hot Topics in Preparedness, that is delivered via a synchronous, Web conferencing system. These monthly, 1-hour sessions focus on key topics related to emergency preparedness for public health professionals and their emergency response partners in the Northwest region. This distance learning series was conceived and implemented as a regional collaborative, overseen by an advisory board representing state, local, and tribal health agencies. Results of session evaluations, challenges, and lessons learned from the first year of the Hot Topics in Preparedness forum are reported. Web conferencing is a popular, convenient, and effective strategy for delivering training in the rapidly changing field of preparedness across a large geographic region.

The time and spatial behavior of solar flare proton anisotropies observed in deep space on Pioneers 10 and 11

NASA Technical Reports Server (NTRS)

Mccarthy, J.; Ogallagher, J. J.

1975-01-01

The anisotropy of solar flare protons from the direction of the 'garden hose' magnetic field line has been analyzed for 24 events observed by the University of Chicago experiment on Pioneers 10 and 11 in 1972 and 1973. The anisotropy versus time profiles during individual events are in general consistent with diffusive propagation, but several cases are observed where the decay is better described by an exponential time decay. The anisotropy amplitude evaluated at the time of maximum intensity for each event shows evidence for a gradual decrease with increasing distance from the sun which is qualitatively consistent with diffusive propagation and suggests that the effective interplanetary diffusion coefficient parallel to the magnetic field increases slowly with heliocentric distance.

Metric projection for dynamic multiplex networks.

PubMed

Jurman, Giuseppe

2016-08-01

Evolving multiplex networks are a powerful model for representing the dynamics along time of different phenomena, such as social networks, power grids, biological pathways. However, exploring the structure of the multiplex network time series is still an open problem. Here we propose a two-step strategy to tackle this problem based on the concept of distance (metric) between networks. Given a multiplex graph, first a network of networks is built for each time step, and then a real valued time series is obtained by the sequence of (simple) networks by evaluating the distance from the first element of the series. The effectiveness of this approach in detecting the occurring changes along the original time series is shown on a synthetic example first, and then on the Gulf dataset of political events.

Is your prescription of distance running shoes evidence-based?

PubMed

Richards, C E; Magin, P J; Callister, R

2009-03-01

To determine whether the current practice of prescribing distance running shoes featuring elevated cushioned heels and pronation control systems tailored to the individual's foot type is evidence-based. MEDLINE (1950-May 2007), CINAHL (1982-May 2007), EMBASE (1980-May 2007), PsychInfo (1806-May 2007), Cochrane Database of Systematic Reviews (2(nd) Quarter 2007), Cochrane Central Register of Controlled trials (2(nd) Quarter 2007), SPORTSDiscus (1985-May 2007) and AMED (1985-May 2007). English language articles were identified via keyword and medical subject headings (MeSH) searches of the above electronic databases. With these searches and the subsequent review process, controlled trials or systematic reviews were sought in which the study population included adult recreational or competitive distance runners, the exposure was distance running, the intervention evaluated was a running shoe with an elevated cushioned heel and pronation control systems individualised to the wearer's foot type, and the outcome measures included either running injury rates, distance running performance, osteoarthritis risk, physical activity levels, or overall health and wellbeing. The quality of these studies and their findings were then evaluated. No original research that met the study criteria was identified either directly or via the findings of the six systematic reviews identified. The prescription of this shoe type to distance runners is not evidence-based.

Automatic lung nodule matching for the follow-up in temporal chest CT scans

NASA Astrophysics Data System (ADS)

Hong, Helen; Lee, Jeongjin; Shin, Yeong Gil

2006-03-01

We propose a fast and robust registration method for matching lung nodules of temporal chest CT scans. Our method is composed of four stages. First, the lungs are extracted from chest CT scans by the automatic segmentation method. Second, the gross translational mismatch is corrected by the optimal cube registration. This initial registration does not require extracting any anatomical landmarks. Third, initial alignment is step by step refined by the iterative surface registration. To evaluate the distance measure between surface boundary points, a 3D distance map is generated by the narrow-band distance propagation, which drives fast and robust convergence to the optimal location. Fourth, nodule correspondences are established by the pairs with the smallest Euclidean distances. The results of pulmonary nodule alignment of twenty patients are reported on a per-center-of mass point basis using the average Euclidean distance (AED) error between corresponding nodules of initial and follow-up scans. The average AED error of twenty patients is significantly reduced to 4.7mm from 30.0mm by our registration. Experimental results show that our registration method aligns the lung nodules much faster than the conventional ones using a distance measure. Accurate and fast result of our method would be more useful for the radiologist's evaluation of pulmonary nodules on chest CT scans.

Integrating Telepresence Robots Into Nursing Simulation.

PubMed

Rudolph, Alexandra; Vaughn, Jacqueline; Crego, Nancy; Hueckel, Remi; Kuszajewski, Michele; Molloy, Margory; Brisson, Raymond; Shaw, Ryan J

This article provides an overview of the use of telepresence robots in clinical practice and describes an evaluation of an educational project in which distance-based nurse practitioner students used telepresence robots in clinical simulations with on-campus Accelerated Bachelor of Science in Nursing students. The results of this project suggest that the incorporation of telepresence in simulation is an effective method to promote engagement, satisfaction, and self-confidence in learning.

Narrative processing of entertainment media and mental illness stigma.

PubMed

Caputo, Nicole Mossing; Rouner, Donna

2011-10-01

This study examined the narrative effects of familiarity, transportation, whether a story is factual or fiction, and perceived realism on the stigmatizing behavior of social distancing behavior. A sample of N = 137 participants watched a commercial movie about mental illness. Genre was manipulated to determine whether fiction or nonfiction impacted social distancing behavior. Although there was no effect of the genre manipulation, transportation was found to have a relationship with social distancing, with the more relevant the participants found the story, the lower they demonstrated social distancing behavior. How much participants identified with the main character was found to have a partial mediating effect between perceived story relevance and social distancing behavior.

Analysis of clinically important factors on the performance of advanced hydraulic, microprocessor-controlled exo-prosthetic knee joints based on 899 trial fittings

PubMed Central

Hahn, Andreas; Lang, Michael; Stuckart, Claudia

2016-01-01

Abstract The objective of this work is to evaluate whether clinically important factors may predict an individual's capability to utilize the functional benefits provided by an advanced hydraulic, microprocessor-controlled exo-prosthetic knee component. This retrospective cross-sectional cohort analysis investigated the data of above knee amputees captured during routine trial fittings. Prosthetists rated the performance indicators showing the functional benefits of the advanced maneuvering capabilities of the device. Subjects were asked to rate their perception. Simple and multiple linear and logistic regression was applied. Data from 899 subjects with demographics typical for the population were evaluated. Ability to vary gait speed, perform toileting, and ascend stairs were identified as the most sensitive performance predictors. Prior C-Leg users showed benefits during advanced maneuvering. Variables showed plausible and meaningful effects, however, could not claim predictive power. Mobility grade showed the largest effect but also failed to be predictive. Clinical parameters such as etiology, age, mobility grade, and others analyzed here do not suffice to predict individual potential. Daily walking distance may pose a threshold value and be part of a predictive instrument. Decisions based solely on single parameters such as mobility grade rating or walking distance seem to be questionable. PMID:27828871

Analysis of clinically important factors on the performance of advanced hydraulic, microprocessor-controlled exo-prosthetic knee joints based on 899 trial fittings.

PubMed

Hahn, Andreas; Lang, Michael; Stuckart, Claudia

2016-11-01

The objective of this work is to evaluate whether clinically important factors may predict an individual's capability to utilize the functional benefits provided by an advanced hydraulic, microprocessor-controlled exo-prosthetic knee component.This retrospective cross-sectional cohort analysis investigated the data of above knee amputees captured during routine trial fittings. Prosthetists rated the performance indicators showing the functional benefits of the advanced maneuvering capabilities of the device. Subjects were asked to rate their perception. Simple and multiple linear and logistic regression was applied.Data from 899 subjects with demographics typical for the population were evaluated. Ability to vary gait speed, perform toileting, and ascend stairs were identified as the most sensitive performance predictors. Prior C-Leg users showed benefits during advanced maneuvering. Variables showed plausible and meaningful effects, however, could not claim predictive power. Mobility grade showed the largest effect but also failed to be predictive.Clinical parameters such as etiology, age, mobility grade, and others analyzed here do not suffice to predict individual potential. Daily walking distance may pose a threshold value and be part of a predictive instrument. Decisions based solely on single parameters such as mobility grade rating or walking distance seem to be questionable.

Chromosome neighborhood composition determines translocation outcomes after exposure to high-dose radiation in primary cells.

PubMed

Brianna Caddle, Lura; Grant, Jeremy L; Szatkiewicz, Jin; van Hase, Johann; Shirley, Bobbi-Jo; Bewersdorf, Joerg; Cremer, Christoph; Arneodo, Alain; Khalil, Andre; Mills, Kevin D

2007-01-01

Radiation exposure is an occupational hazard for military personnel, some health care professionals, airport security screeners, and medical patients, with some individuals at risk for acute, high-dose exposures. Therefore, the biological effects of radiation, especially the potential for chromosome damage, are major occupational and health concerns. However, the biophysical mechanisms of chromosome instability subsequent to radiation-induced DNA damage are poorly understood. It is clear that interphase chromosomes occupy discrete structural and functional subnuclear domains, termed chromosome territories (CT), which may be organized into 'neighborhoods' comprising groups of specific CTs. We directly evaluated the relationship between chromosome positioning, neighborhood composition, and translocation partner choice in primary lymphocytes, using a cell-based system in which we could induce multiple, concentrated DNA breaks via high-dose irradiation. We critically evaluated mis-rejoining profiles and tested whether breaks occurring nearby were more likely to fuse than breaks occurring at a distance. We show that CT neighborhoods comprise heterologous chromosomes, within which inter-CT distances directly relate to translocation partner choice. These findings demonstrate that interphase chromosome arrangement is a principal factor in genomic instability outcomes in primary lymphocytes, providing a structural context for understanding the biological effects of radiation exposure, and the molecular etiology of tumor-specific translocation patterns.

Experimental and numerical investigation of laser shock synchronous welding and forming of Copper/Aluminum

NASA Astrophysics Data System (ADS)

Wang, Xiao; Zhang, Hongfeng; Shen, Zongbao; Li, Jianwen; Qian, Qing; Liu, Huixia

2016-11-01

A novel laser shock synchronous welding and forming method is introduced, which utilizes laser-induced shock waves to accelerate the flyer plate towards the base plate to achieve the joining of dissimilar metals and forming in a specific shape of mold. The samples were obtained with different laser energies and standoff distances. The surface morphology and roughness of the samples were greatly affected by the laser energy and standoff distances. Fittability was investigated to examine the forming accuracy. The results showed that the samples replicate the mold features well. Straight and wavy interfaces with un-bonded regions in the center were observed through metallographic analysis. Moreover, Energy Disperse Spectroscopy analysis was conducted on the welding interface, and the results indicated that a short-distance elemental diffusion emerged in the welding interface. The nanoindentation hardness of the welding regions was measured to evaluate the welding interface. In addition, the Smoothed Particle Hydrodynamics method was employed to simulate the welding and forming process. It was shown that different standoff distances significantly affected the size of the welding regions and interface waveform characteristics. The numerical analysis results indicated that the opposite shear stress direction and effective plastic strain above a certain threshold are essential to successfully obtain welding and forming workpiece.

Vehicular road influence areas

NASA Astrophysics Data System (ADS)

Huertas, María E.; Huertas, José I.; Valencia, Alexander

2017-02-01

Vehicle operation over paved and unpaved roads is an emission source that significantly contributes to air pollution. Emissions are derived from vehicle exhaust pipes and re-suspension of particulate matter generated by wind erosion and tire to road surface interactions. Environmental authorities require a methodology to evaluate road impact areas, which enable managers to initiate counter-measures, particularly under circumstances where historic meteorological and/or air quality data is unavailable. The present study describes an analytical and experimental work developed to establish a simplified methodology to estimate the area influenced by vehicular roads. AERMOD was chosen to model pollutant dispersion generated by two roads of common attributes (straight road over flat terrain) under the effects of several arbitrary chosen weather conditions. The resulting pollutant concentration vs. Distance curves collapsed into a single curve when concentration and distance were expressed as dimensionless numbers and this curve can be described by a beta distribution function. This result implied that average concentration at a given distance was proportional to emission intensity and that it showed minor sensitivity to meteorological conditions. Therefore, road influence was defined by the area adjacent to the road limited by distance at which the beta distribution function equaled the limiting value specified by the national air quality standard for the pollutant under consideration.