A line transect model for aerial surveys

USGS Publications Warehouse

Quang, Pham Xuan; Lanctot, Richard B.

1991-01-01

We employ a line transect method to estimate the density of the common and Pacific loon in the Yukon Flats National Wildlife Refuge from aerial survey data. Line transect methods have the advantage of automatically taking into account “visibility bias” due to detectability difference of animals at different distances from the transect line. However, line transect methods must overcome two difficulties when applied to inaccurate recording of sighting distances due to high travel speeds, so that in fact only a few reliable distance class counts are available. We propose a unimodal detection function that provides an estimate of the effective area lost due to the blind strip, under the assumption that a line of perfect detection exists parallel to the transect line. The unimodal detection function can also be applied when a blind strip is absent, and in certain instances when the maximum probability of detection is less than 100%. A simple bootstrap procedure to estimate standard error is illustrated. Finally, we present results from a small set of Monte Carlo experiments.

Assessment of the line transect method: an examination of the spatial patterns of down and standing dead wood

Treesearch

Duncan C. Lutes

2002-01-01

The line transect method, its underlying assumptions, and the spatial patterning of down and standing pieces of dead wood were examined at the Tenderfoot Creek Experimental Forest in central Montana. The accuracy of the line transect method was not determined due to conflicting results of t-tests and ordinary least squares regression. In most instances down pieces were...

Overview: DVD-video disc set of seafloor transects during USGS research cruises in the Pacific Ocean

USGS Publications Warehouse

Chezar, Henry; Newman, Ivy

2006-01-01

Many USGS research programs involve the gathering of underwater seafloor video footage. This footage was captured on a variety of media, including Beta III and VHS tapes. Much of this media is now deteriorating, prompting the migration of this video footage onto DVD-Video discs. Advantages of using DVD-Video discs are: less storage space, ease of transport, wider distribution, and non-degradational viewing of the media. The videos in this particular collection (328 of them) were made on the ocean floor under President Reagan's Exclusive Economic Zone proclamation of 1983. There are now five copies of these 328 discs in existence: at the USGS libraries in Menlo Park, Calif., Denver, Colo., and Reston, Va.; at the USGS Publications Warehouse (masters from which to make copies for customers); and Hank Chezar's USGS Western Coastal and Marine Geology team archives. The purpose of Open-File Report 2004-1101 is to provide users with a listing of the available DVD-Video discs (with their Open-File Report numbers) along with a brief description of their associated USGS research activities. Each disc was created by first encoding the source video and audio into MPEG-2 streams using the MediaPress Pro hardware encoder. A menu for the disc was then made using Adobe Photoshop 6.0. The disc was then authored using DVD Studio Pro and subsequently written onto a DVD-R recordable disc.

The "Tracked Roaming Transect" and distance sampling methods increase the efficiency of underwater visual censuses.

PubMed

Irigoyen, Alejo J; Rojo, Irene; Calò, Antonio; Trobbiani, Gastón; Sánchez-Carnero, Noela; García-Charton, José A

2018-01-01

Underwater visual census (UVC) is the most common approach for estimating diversity, abundance and size of reef fishes in shallow and clear waters. Abundance estimation through UVC is particularly problematic in species occurring at low densities and/or highly aggregated because of their high variability at both spatial and temporal scales. The statistical power of experiments involving UVC techniques may be increased by augmenting the number of replicates or the area surveyed. In this work we present and test the efficiency of an UVC method based on diver towed GPS, the Tracked Roaming Transect (TRT), designed to maximize transect length (and thus the surveyed area) with respect to diving time invested in monitoring, as compared to Conventional Strip Transects (CST). Additionally, we analyze the effect of increasing transect width and length on the precision of density estimates by comparing TRT vs. CST methods using different fixed widths of 6 and 20 m (FW3 and FW10, respectively) and the Distance Sampling (DS) method, in which perpendicular distance of each fish or group of fishes to the transect line is estimated by divers up to 20 m from the transect line. The TRT was 74% more time and cost efficient than the CST (all transect widths considered together) and, for a given time, the use of TRT and/or increasing the transect width increased the precision of density estimates. In addition, since with the DS method distances of fishes to the transect line have to be estimated, and not measured directly as in terrestrial environments, errors in estimations of perpendicular distances can seriously affect DS density estimations. To assess the occurrence of distance estimation errors and their dependence on the observer's experience, a field experiment using wooden fish models was performed. We tested the precision and accuracy of density estimators based on fixed widths and the DS method. The accuracy of the estimates was measured comparing the actual total abundance with those estimated by divers using FW3, FW10, and DS estimators. Density estimates differed by 13% (range 0.1-31%) from the actual values (average = 13.09%; median = 14.16%). Based on our results we encourage the use of the Tracked Roaming Transect with Distance Sampling (TRT+DS) method for improving density estimates of species occurring at low densities and/or highly aggregated, as well as for exploratory rapid-assessment surveys in which divers could gather spatial ecological and ecosystem information on large areas during UVC.

The "Tracked Roaming Transect" and distance sampling methods increase the efficiency of underwater visual censuses

PubMed Central

2018-01-01

Underwater visual census (UVC) is the most common approach for estimating diversity, abundance and size of reef fishes in shallow and clear waters. Abundance estimation through UVC is particularly problematic in species occurring at low densities and/or highly aggregated because of their high variability at both spatial and temporal scales. The statistical power of experiments involving UVC techniques may be increased by augmenting the number of replicates or the area surveyed. In this work we present and test the efficiency of an UVC method based on diver towed GPS, the Tracked Roaming Transect (TRT), designed to maximize transect length (and thus the surveyed area) with respect to diving time invested in monitoring, as compared to Conventional Strip Transects (CST). Additionally, we analyze the effect of increasing transect width and length on the precision of density estimates by comparing TRT vs. CST methods using different fixed widths of 6 and 20 m (FW3 and FW10, respectively) and the Distance Sampling (DS) method, in which perpendicular distance of each fish or group of fishes to the transect line is estimated by divers up to 20 m from the transect line. The TRT was 74% more time and cost efficient than the CST (all transect widths considered together) and, for a given time, the use of TRT and/or increasing the transect width increased the precision of density estimates. In addition, since with the DS method distances of fishes to the transect line have to be estimated, and not measured directly as in terrestrial environments, errors in estimations of perpendicular distances can seriously affect DS density estimations. To assess the occurrence of distance estimation errors and their dependence on the observer’s experience, a field experiment using wooden fish models was performed. We tested the precision and accuracy of density estimators based on fixed widths and the DS method. The accuracy of the estimates was measured comparing the actual total abundance with those estimated by divers using FW3, FW10, and DS estimators. Density estimates differed by 13% (range 0.1–31%) from the actual values (average = 13.09%; median = 14.16%). Based on our results we encourage the use of the Tracked Roaming Transect with Distance Sampling (TRT+DS) method for improving density estimates of species occurring at low densities and/or highly aggregated, as well as for exploratory rapid-assessment surveys in which divers could gather spatial ecological and ecosystem information on large areas during UVC. PMID:29324887

Sampling coarse woody debris along spoked transects

Treesearch

Paul C. Van Deusen; Jeffery H. Gove

2011-01-01

Line transects are commonly used for sampling coarse woody debris (CWD). The USDA Forest Service Forest Inventory and Analysis programme uses a variant of this method that involves sampling for CWD along transects that radiate from the centre of a circular plot-like spokes on a wheel. A new approach for analysis of data collected with spoked transects is developed....

Lead burdens and behavioral impairments of the lined shore crab Pachygrapsus crassipes

USGS Publications Warehouse

Hui, Clifford A.

2002-01-01

Unless a correction is made, population estimates derived from a sample of belt transects will be biased if a fraction of, the individuals on the sample transects are not counted. An approach, useful for correcting this bias when sampling immotile populations using transects of a fixed width, is presented. The method assumes that a searcher's ability to find objects near the center of the transect is nearly perfect. The method utilizes a mathematical equation, estimated from the data, to represent the searcher's inability to find all objects at increasing distances from the center of the transect. An example of the analysis of data, formation of the equation, and application is presented using waterfowl nesting data collected in Colorado.

Measuring Historical Coastal Change using GIS and the Change Polygon Approach

USGS Publications Warehouse

Smith, M.J.; Cromley, R.G.

2012-01-01

This study compares two automated approaches, the transect-from-baseline technique and a new change polygon method, for quantifying historical coastal change over time. The study shows that the transect-from-baseline technique is complicated by choice of a proper baseline as well as generating transects that intersect with each other rather than with the nearest shoreline. The change polygon method captures the full spatial difference between the positions of the two shorelines and average coastal change is the defined as the ratio of the net area divided by the shoreline length. Although then change polygon method is sensitive to the definition and measurement of shoreline length, the results are more invariant to parameter changes than the transect-from-baseline method, suggesting that the change polygon technique may be a more robust coastal change method. ?? 2012 Blackwell Publishing Ltd.

A log-linear model approach to estimation of population size using the line-transect sampling method

USGS Publications Warehouse

Anderson, D.R.; Burnham, K.P.; Crain, B.R.

1978-01-01

The technique of estimating wildlife population size and density using the belt or line-transect sampling method has been used in many past projects, such as the estimation of density of waterfowl nestling sites in marshes, and is being used currently in such areas as the assessment of Pacific porpoise stocks in regions of tuna fishing activity. A mathematical framework for line-transect methodology has only emerged in the last 5 yr. In the present article, we extend this mathematical framework to a line-transect estimator based upon a log-linear model approach.

Mobile acoustic transects miss rare bat species: implications of survey method and spatio-temporal sampling for monitoring bats.

PubMed

Braun de Torrez, Elizabeth C; Wallrichs, Megan A; Ober, Holly K; McCleery, Robert A

2017-01-01

Due to increasing threats facing bats, long-term monitoring protocols are needed to inform conservation strategies. Effective monitoring should be easily repeatable while capturing spatio-temporal variation. Mobile acoustic driving transect surveys ('mobile transects') have been touted as a robust, cost-effective method to monitor bats; however, it is not clear how well mobile transects represent dynamic bat communities, especially when used as the sole survey approach. To assist biologists who must select a single survey method due to resource limitations, we assessed the effectiveness of three acoustic survey methods at detecting species richness in a vast protected area (Everglades National Park): (1) mobile transects, (2) stationary surveys that were strategically located by sources of open water and (3) stationary surveys that were replicated spatially across the landscape. We found that mobile transects underrepresented bat species richness compared to stationary surveys across all major vegetation communities and in two distinct seasons (dry/cool and wet/warm). Most critically, mobile transects failed to detect three rare bat species, one of which is federally endangered. Spatially replicated stationary surveys did not estimate higher species richness than strategically located stationary surveys, but increased the rate at which species were detected in one vegetation community. The survey strategy that detected maximum species richness and the highest mean nightly species richness with minimal effort was a strategically located stationary detector in each of two major vegetation communities during the wet/warm season.

LIDAR optical rugosity of coral reefs in Biscayne National Park, Florida

USGS Publications Warehouse

Brock, J.C.; Wright, C.W.; Clayton, T.D.; Nayegandhi, A.

2004-01-01

The NASA Experimental Advanced Airborne Research Lidar (EAARL), a temporal waveform-resolving, airborne, green wavelength LIDAR (light detection and ranging), is designed to measure the submeter-scale topography of shallow reef substrates. Topographic variability is a prime component of habitat complexity, an ecological factor that both expresses and controls the abundance and distribution of many reef organisms. Following the acquisition of EAARL coverage over both mid-platform patch reefs and shelf-margin bank reefs within Biscayne National Park in August 2002, EAARL-based optical indices of topographic variability were evaluated at 15 patch reef and bank reef sites. Several sites were selected to match reefs previously evaluated in situ along underwater video and belt transects. The analysis used large populations of submarine topographic transects derived from the examination of closely spaced laser spot reflections along LIDAR raster scans. At all 15 sites, each LIDAR transect was evaluated separately to determine optical rugosity (Rotran), and the average elevation difference between adjacent points (Av(??E ap)). Further, the whole-site mean and maximum values of Ro tran and Av(??Eap) for the entire population of transects at each analysis site, along with their standard deviations, were calculated. This study revealed that the greater habitat complexity of inshore patch reefs versus outer bank reefs results in relative differences in topographic complexity that can be discerned in the laser returns. Accordingly, LIDAR sensing of optical rugosity is proposed as a complementary new technique for the rapid assessment of shallow coral reefs. ?? Springer-Verlag 2004.

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.

Quantification of Massive Seasonal Aggregations of Blacktip Sharks (Carcharhinus limbatus) in Southeast Florida

PubMed Central

Kajiura, Stephen M.; Tellman, Shari L.

2016-01-01

Southeast Florida witnesses an enormous seasonal influx of upper trophic level marine predators each year as massive aggregations of migrating blacktip sharks (Carcharhinus limbatus) overwinter in nearshore waters. The narrow shelf and close proximity of the Gulf Stream current to the Palm Beach County shoreline drive tens of thousands of sharks to the shallow, coastal environment. This natural bottleneck provides a unique opportunity to estimate relative abundance. Over a four year period from 2011–2014, an aerial survey was flown approximately biweekly along the length of Palm Beach County. A high definition video camera and digital still camera mounted out of the airplane window provided a continuous record of the belt transect which extended 200 m seaward from the shoreline between Boca Raton Inlet and Jupiter Inlet. The number of sharks within the survey transect was directly counted from the video. Shark abundance peaked in the winter (January-March) with a maximum in 2011 of 12,128 individuals counted within the 75.6 km-2 belt transect. This resulted in a maximum density of 803.2 sharks km-2. By the late spring (April-May), shark abundance had sharply declined to 1.1% of its peak, where it remained until spiking again in January of the following year. Shark abundance was inversely correlated with water temperature and large numbers of sharks were found only when water temperatures were less than 25°C. Shark abundance was also correlated with day of the year but not with barometric pressure. Although shark abundance was not correlated with photoperiod, the departure of the sharks from southeast Florida occurred around the vernal equinox. The shark migration along the United States eastern seaboard corresponds spatially and temporally with the spawning aggregations of various baitfish species. These baseline abundance data can be compared to future studies to determine if shark population size is changing and if sharks are restricting their southward migration as global water temperatures increase. PMID:27027502

Quantification of Massive Seasonal Aggregations of Blacktip Sharks (Carcharhinus limbatus) in Southeast Florida.

PubMed

Kajiura, Stephen M; Tellman, Shari L

2016-01-01

Southeast Florida witnesses an enormous seasonal influx of upper trophic level marine predators each year as massive aggregations of migrating blacktip sharks (Carcharhinus limbatus) overwinter in nearshore waters. The narrow shelf and close proximity of the Gulf Stream current to the Palm Beach County shoreline drive tens of thousands of sharks to the shallow, coastal environment. This natural bottleneck provides a unique opportunity to estimate relative abundance. Over a four year period from 2011-2014, an aerial survey was flown approximately biweekly along the length of Palm Beach County. A high definition video camera and digital still camera mounted out of the airplane window provided a continuous record of the belt transect which extended 200 m seaward from the shoreline between Boca Raton Inlet and Jupiter Inlet. The number of sharks within the survey transect was directly counted from the video. Shark abundance peaked in the winter (January-March) with a maximum in 2011 of 12,128 individuals counted within the 75.6 km(-2) belt transect. This resulted in a maximum density of 803.2 sharks km(-2). By the late spring (April-May), shark abundance had sharply declined to 1.1% of its peak, where it remained until spiking again in January of the following year. Shark abundance was inversely correlated with water temperature and large numbers of sharks were found only when water temperatures were less than 25 °C. Shark abundance was also correlated with day of the year but not with barometric pressure. Although shark abundance was not correlated with photoperiod, the departure of the sharks from southeast Florida occurred around the vernal equinox. The shark migration along the United States eastern seaboard corresponds spatially and temporally with the spawning aggregations of various baitfish species. These baseline abundance data can be compared to future studies to determine if shark population size is changing and if sharks are restricting their southward migration as global water temperatures increase.

Quantification of massive seasonal aggregations of blacktip sharks ( Carcharhinus limbatus) in Southeast Florida

DOE PAGES

Kajiura, Stephen M.; Tellman, Shari L.; Patterson, Heather M.

2016-03-30

Southeast Florida witnesses an enormous seasonal influx of upper trophic level marine predators each year as massive aggregations of migrating blacktip sharks ( Carcharhinus limbatus) overwinter in nearshore waters. The narrow shelf and close proximity of the Gulf Stream current to the Palm Beach County shoreline drive tens of thousands of sharks to the shallow, coastal environment. This natural bottleneck provides a unique opportunity to estimate relative abundance. Over a four year period from 2011–2014, an aerial survey was flown approximately biweekly along the length of Palm Beach County. A high definition video camera and digital still camera mounted outmore » of the airplane window provided a continuous record of the belt transect which extended 200 m seaward from the shoreline between Boca Raton Inlet and Jupiter Inlet. The number of sharks within the survey transect was directly counted from the video. Shark abundance peaked in the winter (January-March) with a maximum in 2011 of 12,128 individuals counted within the 75.6 km -2 belt transect. This resulted in a maximum density of 803.2 sharks km -2. By the late spring (April-May), shark abundance had sharply declined to 1.1% of its peak, where it remained until spiking again in January of the following year. Shark abundance was inversely correlated with water temperature and large numbers of sharks were found only when water temperatures were less than 25°C. Shark abundance was also correlated with day of the year but not with barometric pressure. Although shark abundance was not correlated with photoperiod, the departure of the sharks from southeast Florida occurred around the vernal equinox. The shark migration along the United States eastern seaboard corresponds spatially and temporally with the spawning aggregations of various baitfish species. As a result, these baseline abundance data can be compared to future studies to determine if shark population size is changing and if sharks are restricting their southward migration as global water temperatures increase.« less

Quantification of massive seasonal aggregations of blacktip sharks ( Carcharhinus limbatus) in Southeast Florida

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

Kajiura, Stephen M.; Tellman, Shari L.; Patterson, Heather M.

Southeast Florida witnesses an enormous seasonal influx of upper trophic level marine predators each year as massive aggregations of migrating blacktip sharks ( Carcharhinus limbatus) overwinter in nearshore waters. The narrow shelf and close proximity of the Gulf Stream current to the Palm Beach County shoreline drive tens of thousands of sharks to the shallow, coastal environment. This natural bottleneck provides a unique opportunity to estimate relative abundance. Over a four year period from 2011–2014, an aerial survey was flown approximately biweekly along the length of Palm Beach County. A high definition video camera and digital still camera mounted outmore » of the airplane window provided a continuous record of the belt transect which extended 200 m seaward from the shoreline between Boca Raton Inlet and Jupiter Inlet. The number of sharks within the survey transect was directly counted from the video. Shark abundance peaked in the winter (January-March) with a maximum in 2011 of 12,128 individuals counted within the 75.6 km -2 belt transect. This resulted in a maximum density of 803.2 sharks km -2. By the late spring (April-May), shark abundance had sharply declined to 1.1% of its peak, where it remained until spiking again in January of the following year. Shark abundance was inversely correlated with water temperature and large numbers of sharks were found only when water temperatures were less than 25°C. Shark abundance was also correlated with day of the year but not with barometric pressure. Although shark abundance was not correlated with photoperiod, the departure of the sharks from southeast Florida occurred around the vernal equinox. The shark migration along the United States eastern seaboard corresponds spatially and temporally with the spawning aggregations of various baitfish species. As a result, these baseline abundance data can be compared to future studies to determine if shark population size is changing and if sharks are restricting their southward migration as global water temperatures increase.« less

Developing accurate survey methods for estimating population sizes and trends of the critically endangered Nihoa Millerbird and Nihoa Finch.

USGS Publications Warehouse

Gorresen, P. Marcos; Camp, Richard J.; Brinck, Kevin W.; Farmer, Chris

2012-01-01

Point-transect surveys indicated that millerbirds were more abundant than shown by the striptransect method, and were estimated at 802 birds in 2010 (95%CI = 652 – 964) and 704 birds in 2011 (95%CI = 579 – 837). Point-transect surveys yielded population estimates with improved precision which will permit trends to be detected in shorter time periods and with greater statistical power than is available from strip-transect survey methods. Mean finch population estimates and associated uncertainty were not markedly different among the three survey methods, but the performance of models used to estimate density and population size are expected to improve as the data from additional surveys are incorporated. Using the pointtransect survey, the mean finch population size was estimated at 2,917 birds in 2010 (95%CI = 2,037 – 3,965) and 2,461 birds in 2011 (95%CI = 1,682 – 3,348). Preliminary testing of the line-transect method in 2011 showed that it would not generate sufficient detections to effectively model bird density, and consequently, relatively precise population size estimates. Both species were fairly evenly distributed across Nihoa and appear to occur in all or nearly all available habitat. The time expended and area traversed by observers was similar among survey methods; however, point-transect surveys do not require that observers walk a straight transect line, thereby allowing them to avoid culturally or biologically sensitive areas and minimize the adverse effects of recurrent travel to any particular area. In general, pointtransect surveys detect more birds than strip-survey methods, thereby improving precision and resulting population size and trend estimation. The method is also better suited for the steep and uneven terrain of Nihoa

Measure of pancreas transection and postoperative pancreatic fistula.

PubMed

Takahashi, Shinichiro; Gotohda, Naoto; Kato, Yuichiro; Konishi, Masaru

2016-05-15

In pancreaticoduodenectomy (PD), a standard protocol for pancreas transection has not been established although the method of pancreas transection might be involved in the occurrence of postoperative pancreatic fistula (POPF). This study aimed to compare whether pancreas transection by ultrasonically activated shears (UAS) or that by scalpel contributed more to POPF development. A prospective database of 171 patients who underwent PD for periampullary tumor at National Cancer Center Hospital East between January 2010 and June 2013 was reviewed. Among the 171 patients, 93 patients with soft pancreas were specifically included in this study. Surgical results and background were compared between patients with pancreas transection by UAS and scalpel to evaluate the effectiveness of UAS on reducing POPF. Body mass index, main pancreatic duct diameter, or other clinicopathologic factors that have been reported as predictive factors for POPF were not significantly different between the two groups. The incidence of all grades of POPF and that of grade B were significantly lower in the scalpel group (52%, 4%) than in the UAS group (74%, 42%). Postoperative complications ≥ grade III were also significantly fewer in the scalpel group. Scalpel transection was less associated with POPF than UAS transection in patients who underwent PD for soft pancreas. The method of pancreas transection plays an important role in the prevention of clinical POPF. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparison of rangeland vegetation sampling techniques in the Central Grasslands

USGS Publications Warehouse

Stohlgren, T.J.; Bull, K.A.; Otsuki, Yuka

1998-01-01

Maintaining native plant diversity, detecting exotic species, and monitoring rare species are becoming important objectives in rangeland conservation. Four rangeland vegetation sampling techniques were compared to see how well they captured local pant diversity. The methods tested included the commonly used Parker transects, Daubenmire transects as modified by the USDA Forest Service, a new transect and 'large quadrat' design proposed by the USDA Agricultural Research Service, and the Modified-Whittaker multi-scale vegetation plot. The 4 methods were superimposed in shortgrass steppe, mixed grass prairie, northern mixed prairie, and tallgrass prairie in the Central Grasslands of the United States with 4 replicates in each prairie type. Analysis of variance tests showed significant method effects and prairie type effects, but no significant method X type interactions for total species richness, the number of native species, the number of species with less than 1 % cover, and the time required for sampling. The methods behaved similarly in each prairie type under a wide variety of grazing regimens. The Parker, large quadrat, and Daubenmire transects significantly underestimated the total species richness and the number of native species in each prairie type, and the number of species with less than 1 % cover in all but the tallgrass prairie type. The transect techniques also consistently missed half the exotic species, including noxious weeds, in each prairie type. The Modified-Whittaker method, which included an exhaustive search for plant species in a 20 x 50 m plot, served as the baseline for species richeness comparisons. For all prairie types, the Modified-Whittaker plot captured an average of 42. (?? 2.4; 1 S.E.) plant species per site compared to 15.9 (?? 1.3), 18.9 (?? 1.2), and 22.8 (?? 1.6) plant species per site using the Parker, large quadrat, and Daubenmire transect methods, respectively. The 4 methods captured most of the dominant species at each site and thus produced similar results for total foliar cover and soil cover. The detection and measurement of exotic plant species were greatly enhanced by using ten 1 m2 subplots in a multi-scale sampling design and searching a larger area (1,000 m2) at each site. Even with 4 replicate sites, the transect methods usually captured, and thus would monitor, 36 to 66 % of the plant species at each site. To evaluate the status and trends of common, rare, and exotic plant species at local, regional, and national scales, innovative, multi-scale methods must replace the commonly used transect methods to the past.

Comparing census methods for the endangered Kirtland's Warbler

Treesearch

John R. Probst; Deahn M. Donner; Mike Worland; Jerry Weinrich; Phillip Huber; Kenneth R. Ennis

2005-01-01

We compared transect counts used for the annual official count of male Kirtland`s Warblers (Dendroica kirtlandii) to an observation-based mapping method of individually sighted males in 155 stands over 10 yrs. The annual census count almost tripled from 1990 to 1999. The transect and observation-based mapping method showed the same increasing trend...

Mobile acoustic transects miss rare bat species: implications of survey method and spatio-temporal sampling for monitoring bats

PubMed Central

Wallrichs, Megan A.; Ober, Holly K.; McCleery, Robert A.

2017-01-01

Due to increasing threats facing bats, long-term monitoring protocols are needed to inform conservation strategies. Effective monitoring should be easily repeatable while capturing spatio-temporal variation. Mobile acoustic driving transect surveys (‘mobile transects’) have been touted as a robust, cost-effective method to monitor bats; however, it is not clear how well mobile transects represent dynamic bat communities, especially when used as the sole survey approach. To assist biologists who must select a single survey method due to resource limitations, we assessed the effectiveness of three acoustic survey methods at detecting species richness in a vast protected area (Everglades National Park): (1) mobile transects, (2) stationary surveys that were strategically located by sources of open water and (3) stationary surveys that were replicated spatially across the landscape. We found that mobile transects underrepresented bat species richness compared to stationary surveys across all major vegetation communities and in two distinct seasons (dry/cool and wet/warm). Most critically, mobile transects failed to detect three rare bat species, one of which is federally endangered. Spatially replicated stationary surveys did not estimate higher species richness than strategically located stationary surveys, but increased the rate at which species were detected in one vegetation community. The survey strategy that detected maximum species richness and the highest mean nightly species richness with minimal effort was a strategically located stationary detector in each of two major vegetation communities during the wet/warm season. PMID:29134138

Line transect estimation of population size: the exponential case with grouped data

USGS Publications Warehouse

Anderson, D.R.; Burnham, K.P.; Crain, B.R.

1979-01-01

Gates, Marshall, and Olson (1968) investigated the line transect method of estimating grouse population densities in the case where sighting probabilities are exponential. This work is followed by a simulation study in Gates (1969). A general overview of line transect analysis is presented by Burnham and Anderson (1976). These articles all deal with the ungrouped data case. In the present article, an analysis of line transect data is formulated under the Gates framework of exponential sighting probabilities and in the context of grouped data.

Trail Transect: A Method for Documenting Trail Changes

Treesearch

R.E. Leonard; A.M. Whitney

1977-01-01

A trail transect that documents trail conditions and changes in trails has been used successfully over the past 3 years to measure soil loss, and changes in trail width and vegetation. The system also can be used to study the relationship between trail degradation and the physical characteristics of the site. Data from trail transects can be useful in determining the...

Estimating nest detection probabilities for white-winged dove nest transects in Tamaulipas, Mexico

USGS Publications Warehouse

Nichols, J.D.; Tomlinson, R.E.; Waggerman, G.

1986-01-01

Nest transects in nesting colonies provide one source of information on White-winged Dove (Zenaida asiatica asiatica) population status and reproduction. Nests are counted along transects using standardized field methods each year in Texas and northeastern Mexico by personnel associated with Mexico's Office of Flora and Fauna, the Texas Parks and Wildlife Department, and the U.S. Fish and Wildlife Service. Nest counts on transects are combined with information on the size of nesting colonies to estimate total numbers of nests in sampled colonies. Historically, these estimates have been based on the actual nest counts on transects and thus have required the assumption that all nests lying within transect boundaries are detected (seen) with a probability of one. Our objectives were to test the hypothesis that nest detection probability is one and, if rejected, to estimate this probability.

Spatial and size-frequency distribution of Acropora (Cnidaria: Scleractinia) species in Chinchorro Bank, Mexican Caribbean: implications for management

NASA Astrophysics Data System (ADS)

Vega-Zepeda, A.; Hernández-Arana, H.; Carricart-Ganivet, J. P.

2007-09-01

The Mexican Government decreed Chinchorro Bank reef as a Biosphere Reserve in 1996. The aim of this study was to evaluate the spatial and size-frequency distribution of Acropora spp. in order to provide further knowledge and tools to enhance management. A field survey was conducted, within six regions, to locate and measure Acropora patches in the reef lagoon. Density, colony size and living tissue cover of Acropora colonies were evaluated using the line-intercept transect technique, combining direct observations and video transects. The results showed that Acropora spp. was preferentially distributed in the southern regions; where cover and density were high. Based on these results and considering that Acropora spp. produces landscape heterogeneity, which in turn generates shelter for other species, including some of considerable economic importance, then at least the South East region should be considered as a key area for Acropora species conservation, and should be included in the Chinchorro Bank management plan.

Imaging fall Chinook salmon redds in the Columbia River with a dual-frequency identification sonar

USGS Publications Warehouse

Tiffan, K.F.; Rondorf, D.W.; Skalicky, J.J.

2004-01-01

We tested the efficacy of a dual-frequency identification sonar (DIDSON) for imaging and enumeration of fall Chinook salmon Oncorhynchus tshawytscha redds in a spawning area below Bonneville Dam on the Columbia River. The DIDSON uses sound to form near-video-quality images and has the advantages of imaging in zero-visibility water and possessing a greater detection range and field of view than underwater video cameras. We suspected that the large size and distinct morphology of a fall Chinook salmon redd would facilitate acoustic imaging if the DIDSON was towed near the river bottom so as to cast an acoustic shadow from the tailspill over the redd pocket. We tested this idea by observing 22 different redds with an underwater video camera, spatially referencing their locations, and then navigating to them while imaging them with the DIDSON. All 22 redds were successfully imaged with the DIDSON. We subsequently conducted redd searches along transects to compare the number of redds imaged by the DIDSON with the number observed using an underwater video camera. We counted 117 redds with the DIDSON and 81 redds with the underwater video camera. Only one of the redds observed with the underwater video camera was not also documented by the DIDSON. In spite of the DIDSON's high cost, it may serve as a useful tool for enumerating fall Chinook salmon redds in conditions that are not conducive to underwater videography.

Use of the transect method in satellite survey missions with application to the infrared astronomical satellite /IRAS/

NASA Technical Reports Server (NTRS)

Mclaughlin, W. I.; Lundy, S. A.; Ling, H. Y.; Stroberg, M. W.

1980-01-01

The coverage of the celestial sphere or the surface of the earth with a narrow-field instrument onboard a satellite can be described by a set of swaths on the sphere. A transect is a curve on this sphere constructed to sample the coverage. At each point on the transect the number of times that the field-of-view of the instrument has passed over the point is recorded. This information is conveniently displayed as an integer-valued histogram over the length of the transect. The effectiveness of the transect method for a particular observing plan and the best placement of the transects depends upon the structure of the set of observations. Survey missions are usually characterized by a somewhat parallel alignment of the instrument swaths. Using autocorrelation and cross-correlation functions among the histograms the structure of a survey has been analyzed into two components, and each is illustrated by a simple mathematical model. The complex, all-sky survey to be performed by the Infrared Astronomical Satellite (IRAS) is synthesized in some detail utilizing the objectives and constraints of that mission. It is seen that this survey possesses the components predicted by the simple models and this information is useful in characterizing the properties of the IRAS survey and the placement of the transects as a function of celestial latitude and certain structural properties of the coverage.

Density (DE)

Treesearch

John F. Caratti

2006-01-01

The FIREMON Density (DE) method is used to assess changes in plant species density and height for a macroplot. This method uses multiple quadrats and belt transects (transects having a width) to sample within plot variation and quantify statistically valid changes in plant species density and height over time. Herbaceous plant species are sampled with quadrats while...

Evaluation of the aesthetics of physical methods of euthanasia of anesthetized rats.

PubMed

Hickman, Debra L; Johnson, Steven W

2011-09-01

Dissection of living brain tissue for in vitro experiments requires the use of a rapid euthanasia method. However, the method must not subject animals to unnecessary pain and must be aesthetically acceptable to experimenters. The purposes of the current study were to assess the aesthetics of 6 euthanasia methods, measure the procedure duration, and evaluate brain for pathology after each procedure. We digitally recorded euthanasia of isoflurane-anesthetized rats by 6 physical methods: anesthetic overdose, cardiac exsanguination, decapitation, closed intrathoracic transection of the great vessels and heart, thoracic percussion, and thoracotomy with rupture of great vessels. Volunteer researchers and animal caretakers watched the video and completed an associated questionnaire. Anesthetic overdose and cardiac exsanguinations were rated most aesthetically pleasing, although these procedures took the longest to complete. In contrast, decapitation and thoracic percussion were the least aesthetically pleasing, but these methods were the quickest. No demographic factor was identified that could predict whether a given euthanasia procedure would be favored for aesthetic reasons, and participants provided a wide variety of rationales for the aesthetic ratings they assigned. Although all of these euthanasia methods meet the criteria of approved methods of euthanasia of anesthetized rats as defined by the AVMA, aesthetic features and the scientific need for rapid euthanasia are both considerations in selecting a method.

Evaluation of the Aesthetics of Physical Methods of Euthanasia of Anesthetized Rats

PubMed Central

Hickman, Debra L; Johnson, Steven W

2011-01-01

Dissection of living brain tissue for in vitro experiments requires the use of a rapid euthanasia method. However, the method must not subject animals to unnecessary pain and must be aesthetically acceptable to experimenters. The purposes of the current study were to assess the aesthetics of 6 euthanasia methods, measure the procedure duration, and evaluate brain for pathology after each procedure. We digitally recorded euthanasia of isoflurane-anesthetized rats by 6 physical methods: anesthetic overdose, cardiac exsanguination, decapitation, closed intrathoracic transection of the great vessels and heart, thoracic percussion, and thoracotomy with rupture of great vessels. Volunteer researchers and animal caretakers watched the video and completed an associated questionnaire. Anesthetic overdose and cardiac exsanguinations were rated most aesthetically pleasing, although these procedures took the longest to complete. In contrast, decapitation and thoracic percussion were the least aesthetically pleasing, but these methods were the quickest. No demographic factor was identified that could predict whether a given euthanasia procedure would be favored for aesthetic reasons, and participants provided a wide variety of rationales for the aesthetic ratings they assigned. Although all of these euthanasia methods meet the criteria of approved methods of euthanasia of anesthetized rats as defined by the AVMA, aesthetic features and the scientific need for rapid euthanasia are both considerations in selecting a method. PMID:22330717

Effects of submarine power transmission cables on a glass sponge reef and associated megafaunal community.

PubMed

Dunham, A; Pegg, J R; Carolsfeld, W; Davies, S; Murfitt, I; Boutillier, J

2015-06-01

We examined the effects of submarine power transmission cable installation and operation on glass sponge reef condition and associated megafauna. Video and still imagery were collected using a Remotely Operated Vehicle twice a year for 4 years following cable installation. The effects of cables on glass sponges were assessed by comparing sponge cover along fixed transects and at marked index sites. Megafauna counts along transects were used to explore the effects on associated community. We found no evidence of cable movement across the sponge reef surface. Live sponge cover was found to be consistently lower along cable transects and at cable index sites compared to controls. Live sponge cover was the lowest (55 ± 1.1% decrease) at cable index sites 1.5 years after installation and recovered to 85 ± 30.6% of the original size over the following 2 years. Our data suggest 100% glass sponge mortality along the direct cable footprint and 15% mortality in the surrounding 1.5 m corridor 3.5 years after cable installation. Growth rate of a new glass sponge was 1 and 3 cm/year in first and second year, respectively, and appeared to be seasonal. We observed a diverse megafaunal community with representatives from 7 phyla and 14 classes. Total megafauna, spot prawn, and other Arthropoda abundances were slightly lower along cable transects although the effect of cable presence was not statistically significant. The following measures could be taken to reduce the amount of damage to glass sponge reefs and associated fauna: routing the cable around reefs, whenever possible, minimizing cable movement across the surface of the reef at installation and routine operation, and assessing potential damage to glass sponges prior to decommissioning. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Divers-Operated Underwater Photogrammetry: Applications in the Study of Antarctic Benthos

NASA Astrophysics Data System (ADS)

Piazza, P.; Cummings, V.; Lohrer, D.; Marini, S.; Marriott, P.; Menna, F.; Nocerino, E.; Peirano, A.; Schiaparelli, S.

2018-05-01

Ecological studies about marine benthic communities received a major leap from the application of a variety of non-destructive sampling and mapping techniques based on underwater image and video recording. The well-established scientific diving practice consists in the acquisition of single path or `round-trip' over elongated transects, with the imaging device oriented in a nadir looking direction. As it may be expected, the application of automatic image processing procedures to data not specifically acquired for 3D modelling can be risky, especially if proper tools for assessing the quality of the produced results are not employed. This paper, born from an international cooperation, focuses on this topic, which is of great interest for ecological and monitoring benthic studies in Antarctica. Several video footages recorded from different scientific teams in different years are processed with an automatic photogrammetric procedure and salient statistical features are reported to critically analyse the derived results. As expected, the inclusion of oblique images from additional lateral strips may improve the expected accuracy in the object space, without altering too much the current video recording practices.

The effect of changes to the method of estimating the pollen count from aerobiological samples.

PubMed

Sikoparija, Branko; Pejak-Šikoparija, Tatjana; Radišić, Predrag; Smith, Matt; Soldevilla, Carmen Galán

2011-02-01

Pollen data have been recorded at Novi Sad in Serbia since 2000. The adopted method of producing pollen counts has been the use of five longitudinal transects that examine 19.64% of total sample surface. However, counting five transects is time consuming and so the main objective of this study is to investigate whether reducing the number to three or even two transects would have a significant effect on daily average and bi-hourly pollen concentrations, as well as the main characteristics of the pollen season and long-term trends. This study has shown that there is a loss of accuracy in daily average and bi-hourly pollen concentrations (an increase in % ERROR) as the sub-sampling area is reduced from five to three or two longitudinal transects. However, this loss of accuracy does not impact on the main characteristics of the season or long-term trends. As a result, this study can be used to justify changing the sub-sampling method used at Novi Sad from five to three longitudinal transects. The use of two longitudinal transects has been ruled out because, although quicker, the counts produced: (a) had the greatest amount of % ERROR, (b) altered the amount of influence of the independent variable on the dependent variable (the slope in regression analysis) and (c) the total sampled surface (7.86%) was less than the minimum requirement recommended by the European Aerobiology Society working group on Quality Control (at least 10% of total slide area).

Total Human Eye Allotransplantation: Developing Surgical Protocols for Donor and Recipient Procedures

PubMed Central

Davidson, Edward H.; Wang, Eric W.; Yu, Jenny Y.; Fernandez-Miranda, Juan C.; Wang, Dawn J.; Richards, Nikisha; Miller, Maxine; Schuman, Joel S.; Washington, Kia M.

2017-01-01

Background Vascularized composite allotransplantation of the eye is an appealing, novel method for reconstruction of the nonfunctioning eye. The authors’ group has established the first orthotopic model for eye transplantation in the rat. With advancements in immunomodulation strategies together with new therapies in neuroregeneration, parallel development of human surgical protocols is vital for ensuring momentum toward eye transplantation in actual patients. Methods Cadaveric donor tissue harvest (n = 8) was performed with orbital exenteration, combined open craniotomy, and endonasal approach to ligate the ophthalmic artery with a cuff of paraclival internal carotid artery, for transection of the optic nerve at the optic chiasm and transection of cranial nerves III to VI and the superior ophthalmic vein at the cavernous sinus. Candidate recipient vessels (superficial temporal/internal maxillary/facial artery and superficial temporal/facial vein) were exposed. Vein grafts were required for all anastomoses. Donor tissue was secured in recipient orbits followed by sequential venous and arterial anastomoses and nerve coaptation. Pedicle lengths and calibers were measured. All steps were timed, photographed, video recorded, and critically analyzed after each operative session. Results The technical feasibility of cadaveric donor procurement and transplantation to cadaveric recipient was established. Mean measurements included optic nerve length (39 mm) and caliber (5 mm), donor artery length (33 mm) and caliber (3 mm), and superior ophthalmic vein length (15 mm) and caliber (0.5 mm). Recipient superficial temporal, internal maxillary artery, and facial artery calibers were 0.8, 2, and 2 mm, respectively; and superior temporal and facial vein calibers were 0.8 and 2.5 mm, respectively. Conclusion This surgical protocol serves as a benchmark for optimization of technique, large-animal model development, and ultimately potentiating the possibility of vision restoration transplantation surgery. PMID:27879599

Do McKinnon lists provide reliable data in bird species frequency? A comparison with transect-based data

NASA Astrophysics Data System (ADS)

Cento, Michele; Scrocca, Roberto; Coppola, Michele; Rossi, Maurizio; Di Giuseppe, Riccardo; Battisti, Corrado; Luiselli, Luca; Amori, Giovanni

2018-05-01

Although occurrence-based listing methods could provide reliable lists of species composition for a site, the effective reliability of this method to provide more detailed information about species frequency (and abundance) has been rarely tested. In this paper, we compared the species frequencies obtained for the same set of species-rich sites (wetlands of central Italy) from two different methods: McKinnon lists and line transects. In all sites we observed: (i) rapid cumulating curves of line transect abundance frequencies toward the asymptote represented by the maximum value in McKinnon occurrence frequency; (ii) a large amount of species having a low frequency with line transect method showing a high range of variation in frequency obtained by McKinnon lists; (iii) a set of species having a subdominant (>0.02-<0.05) and dominant species (>0.05) frequency with line transect showed all the highest value in McKinnon frequency. McKinnon lists provides only a coarse-grained proxy of species frequency of individuals distinguishing only between common species (having the highest values of McKinnon frequency) and rare species (all the other species). Although McKinnon lists have some points of strength, this method does not discriminate the frequencies inside the subset of common species (sub-dominant and dominant species). Therefore, we suggest a cautionary approach when McKinnon frequencies should be used to obtain complex univariate metrics of diversity.

State-space modeling of population sizes and trends in Nihoa Finch and Millerbird

USGS Publications Warehouse

Gorresen, P. Marcos; Brinck, Kevin W.; Camp, Richard J.; Farmer, Chris; Plentovich, Sheldon M.; Banko, Paul C.

2016-01-01

Both of the 2 passerines endemic to Nihoa Island, Hawai‘i, USA—the Nihoa Millerbird (Acrocephalus familiaris kingi) and Nihoa Finch (Telespiza ultima)—are listed as endangered by federal and state agencies. Their abundances have been estimated by irregularly implemented fixed-width strip-transect sampling from 1967 to 2012, from which area-based extrapolation of the raw counts produced highly variable abundance estimates for both species. To evaluate an alternative survey method and improve abundance estimates, we conducted variable-distance point-transect sampling between 2010 and 2014. We compared our results to those obtained from strip-transect samples. In addition, we applied state-space models to derive improved estimates of population size and trends from the legacy time series of strip-transect counts. Both species were fairly evenly distributed across Nihoa and occurred in all or nearly all available habitat. Population trends for Nihoa Millerbird were inconclusive because of high within-year variance. Trends for Nihoa Finch were positive, particularly since the early 1990s. Distance-based analysis of point-transect counts produced mean estimates of abundance similar to those from strip-transects but was generally more precise. However, both survey methods produced biologically unrealistic variability between years. State-space modeling of the long-term time series of abundances obtained from strip-transect counts effectively reduced uncertainty in both within- and between-year estimates of population size, and allowed short-term changes in abundance trajectories to be smoothed into a long-term trend.

Bathymetric and underwater video survey of Lower Granite Reservoir and vicinity, Washington and Idaho, 2009-10

USGS Publications Warehouse

Williams, Marshall L.; Fosness, Ryan L.; Weakland, Rhonda J.

2012-01-01

The U.S. Geological Survey conducted a bathymetric survey of the Lower Granite Reservoir, Washington, using a multibeam echosounder, and an underwater video mapping survey during autumn 2009 and winter 2010. The surveys were conducted as part of the U.S. Army Corps of Engineer's study on sediment deposition and control in the reservoir. The multibeam echosounder survey was performed in 1-mile increments between river mile (RM) 130 and 142 on the Snake River, and between RM 0 and 2 on the Clearwater River. The result of the survey is a digital elevation dataset in ASCII coordinate positioning data (easting, northing, and elevation) useful in rendering a 3×3-foot point grid showing bed elevation and reservoir geomorphology. The underwater video mapping survey was conducted from RM 107.73 to 141.78 on the Snake River and RM 0 to 1.66 on the Clearwater River, along 61 U.S. Army Corps of Engineers established cross sections, and dredge material deposit transects. More than 900 videos and 90 bank photographs were used to characterize the sediment facies and ground-truth the multibeam echosounder data. Combined, the surveys were used to create a surficial sediment facies map that displays type of substrate, level of embeddedness, and presence of silt.

Photographic evaluation of the impacts of bottom fishing on benthic epifauna

USGS Publications Warehouse

Collie, J.S.; Escanero, G.A.; Valentine, P.C.

2000-01-01

The gravel sediment habitat on the northern edge of Georges Bank (East coast of North America) is an important nursery area for juvenile fish, and the site of a productive scallop fishery. During two cruises to this area in 1994 we made photographic transects at sites of varying depths that experience varying degrees of disturbance from otter trawling and scallop dredging. Differences between sites were quantified by analyzing videos and still photographs of the sea bottom. Videos were analyzed for sediment types and organism abundance. In the still photos, the percentages of the bottom covered by bushy, plant-like organisms and colonial worm tubes (Filograna implexa) were determined, as was the presence/absence of encrusting bryozoa. Non-colonial organisms were also identified as specifically as possible and sediment type was quantified. Significant differences between disturbed and undisturbed areas were found for the variables measured in the still photos; colonial epifaunal species were conspicuously less abundant at disturbed sites. Results from the videos and still photos were generally consistent although less detail was visible in the videos. Emergent colonial epifauna provide a complex habitat for shrimp, polychaetes, brittle stars and small fish at undisturbed sites. Bottom fishing removes this epifauna, thereby reducing the complexity and species diversity of the benthic community. (C) 2000 International Council for the Exploration of the Sea.

The transect method: a novel approach to on-farm welfare assessment of commercial turkeys

PubMed Central

Marchewka, Joanna; Estevez, Inma; Vezzoli, Giuseppe; Ferrante, Valentina; Makagon, Maja M.

2015-01-01

Currently, no animal-based protocol for on-farm welfare assessment of commercial turkeys is available. The birds’ size and flighty nature make obtaining a representative sample using traditional methods difficult. The transect walks (TW) approach provides a potential alternative for on-farm assessments of turkey welfare. We compared the TW approach with a traditional method, and data collected as the birds were moved out of the house during the load out process (L). Ten commercial 19- to 20-week-old Hybrid turkey flocks were evaluated (1 flock/house/farm). Half of the flocks were housed on farms deemed as “faring well” by the company, the other half were on “suboptimal” farms. Each house was subdivided longitudinally into 4 transects. Two observers walked the transects in random order, recording the total number of birds per transect that were immobile; lame; aggressive towards a mate; interacting with humans; with visible head, vent, or back wounds; engaging in mounting behaviors; small; featherless; dirty; sick; terminal; or dead. Flocks were re-evaluated on the same day using the individual sampling method (S), where randomly selected birds were scored as they took 10 steps. Flocks were re-assessed within 48 h of the transect evaluation, as birds were funneled out of the house during load out. Using ANOVAs we determined the effects of observers, method, management, and their interactions on proportions of turkeys per house within each category. Outcome parameters were not affected by management (P > 0.05 for all) or observer (P > 0.05 for most), but an assessment method effect was detected (P < 0.05). S differed from the 2 other methods (P < 0.05) for most parameters except aggression towards a mate, back wounds, dirty, sick, and vent wounds. Differences were not detected between data collected using TW and during L, except for dead (P = 0.0007) and immobile (P = 0.007). Results suggest that the TW method is a promising tool for on-farm turkey welfare assessment as it produced results similar to those obtained at L when all birds could be scored individually. PMID:25577791

The transect method: a novel approach to on-farm welfare assessment of commercial turkeys.

PubMed

Marchewka, Joanna; Estevez, Inma; Vezzoli, Giuseppe; Ferrante, Valentina; Makagon, Maja M

2015-01-01

Currently, no animal-based protocol for on-farm welfare assessment of commercial turkeys is available. The birds' size and flighty nature make obtaining a representative sample using traditional methods difficult. The transect walks (TW) approach provides a potential alternative for on-farm assessments of turkey welfare. We compared the TW approach with a traditional method, and data collected as the birds were moved out of the house during the load out process (L). Ten commercial 19- to 20-week-old Hybrid turkey flocks were evaluated (1 flock/house/farm). Half of the flocks were housed on farms deemed as "faring well" by the company, the other half were on "suboptimal" farms. Each house was subdivided longitudinally into 4 transects. Two observers walked the transects in random order, recording the total number of birds per transect that were immobile; lame; aggressive towards a mate; interacting with humans; with visible head, vent, or back wounds; engaging in mounting behaviors; small; featherless; dirty; sick; terminal; or dead. Flocks were re-evaluated on the same day using the individual sampling method (S), where randomly selected birds were scored as they took 10 steps. Flocks were re-assessed within 48 h of the transect evaluation, as birds were funneled out of the house during load out. Using ANOVAs we determined the effects of observers, method, management, and their interactions on proportions of turkeys per house within each category. Outcome parameters were not affected by management (P>0.05 for all) or observer (P>0.05 for most), but an assessment method effect was detected (P<0.05). S differed from the 2 other methods (P<0.05) for most parameters except aggression towards a mate, back wounds, dirty, sick, and vent wounds. Differences were not detected between data collected using TW and during L, except for dead (P=0.0007) and immobile (P=0.007). Results suggest that the TW method is a promising tool for on-farm turkey welfare assessment as it produced results similar to those obtained at L when all birds could be scored individually. © The Author 2015. Published by Oxford University Press on behalf of Poultry Science Association.

Numerical simulations to assess the tracer dilution method for measurement of landfill methane emissions.

PubMed

Taylor, Diane M; Chow, Fotini K; Delkash, Madjid; Imhoff, Paul T

2016-10-01

Landfills are a significant contributor to anthropogenic methane emissions, but measuring these emissions can be challenging. This work uses numerical simulations to assess the accuracy of the tracer dilution method, which is used to estimate landfill emissions. Atmospheric dispersion simulations with the Weather Research and Forecast model (WRF) are run over Sandtown Landfill in Delaware, USA, using observation data to validate the meteorological model output. A steady landfill methane emissions rate is used in the model, and methane and tracer gas concentrations are collected along various transects downwind from the landfill for use in the tracer dilution method. The calculated methane emissions are compared to the methane emissions rate used in the model to find the percent error of the tracer dilution method for each simulation. The roles of different factors are examined: measurement distance from the landfill, transect angle relative to the wind direction, speed of the transect vehicle, tracer placement relative to the hot spot of methane emissions, complexity of topography, and wind direction. Results show that percent error generally decreases with distance from the landfill, where the tracer and methane plumes become well mixed. Tracer placement has the largest effect on percent error, and topography and wind direction both have significant effects, with measurement errors ranging from -12% to 42% over all simulations. Transect angle and transect speed have small to negligible effects on the accuracy of the tracer dilution method. These tracer dilution method simulations provide insight into measurement errors that might occur in the field, enhance understanding of the method's limitations, and aid interpretation of field data. Copyright © 2016 Elsevier Ltd. All rights reserved.

Welfare assessment in broiler farms: transect walks versus individual scoring.

PubMed

Marchewka, J; Watanabe, T T N; Ferrante, V; Estevez, I

2013-10-01

Current scientific approaches to welfare assessment in broilers are based on individual sampling that can be time consuming under field conditions. On the other hand, farmers conduct routine checks based on walks through the house to screen birds' health condition. We adapted the walks through following line transect methodology used in wildlife studies to explore their feasibility as a welfare assessment tool. The aim of this study was to compare broiler welfare assessed by individual sampling and transect walks. We evaluated 6 identically managed flocks. For individual sampling, we collected measures on 150 birds, including weight, breast dirtiness, hock and footpad dermatitis, lameness, and immobility. Transect observations were conducted by slowly walking on randomized paths within each house recording: immobility, lameness, back dirtiness, sickness, agony, and dead. Transect walks allowed detection of small variations (P < 0.003) in the prevalence of most welfare indicators considered with consistency in interobserver reliability (P ≥ 0.05). In addition, assessments across transects were highly consistent (P ≥ 0.05). Individual sampling was also sensitive to differences across houses (P < 0.01) with the exception of immobility (P = 0.783). No differences were found across sampling locations (P ≥ 0.05). However, both methods differed greatly in the frequency of the incidence of the parameters considered. For example, immobility varied from 0.2 ± 0.02% for transect walks to 4 ± 2.3% for individual sampling, whereas lameness varied between 0.8 ± 0.07% and 24.2 ± 4.7% for transect and samplings, respectively. It is possible that the transect approach may have overlooked walking deficiencies because a large number of birds were scored, although if this was the case, the consistency obtained in the scoring across observers and transects would be surprising. Differences may also be related to possibly biased individual sampling procedures, where less mobile and passive individuals may be more likely to be caught. Furthermore the procedure may cause fatigue and fear reactions reducing mobility. Current study provides new insights into constraints and advantages of broiler on-farm assessment methods, which should be considered for designing on-farm welfare assessment protocols.

Detecting swift fox: Smoked-plate scent stations versus spotlighting

Treesearch

Daniel W. Uresk; Kieth E. Severson; Jody Javersak

2003-01-01

We compared two methods of detecting presence of swift fox: smoked-plate scent stations and spotlight counts. Tracks were counted on ten 1-mile (1.6-km) transects with bait/tracking plate stations every 0.1 mile (0.16 km). Vehicle spotlight counts were conducted on the same transects. Methods were compared with Spearman's rank order correlation. Repeated measures...

Evaluating the use of drone photogrammetry for measurement of stream channel morphology and response to high flow events

NASA Astrophysics Data System (ADS)

Price, Katie; Ballow, William

2015-04-01

Traditional high-precision survey methods for stream channel measurement are labor-intensive and require wadeability or boat access to streams. These conditions limit the number of sites researchers are able to study and generally prohibit the possibility of repeat channel surveys to evaluate short-term fluctuations in channel morphology. In recent years, unmanned aerial vehicles (drones) equipped with photo and video capabilities have become widely available and affordable. Concurrently, developments in photogrammetric software offer unprecedented mapping and 3D rendering capabilities of drone-captured photography. In this study, we evaluate the potential use of drone-mounted cameras for detailed stream channel morphometric analysis. We used a relatively low-cost drone (DJI Phantom 2+ Vision) and commercially available, user friendly software (Agisoft Photscan) for photogrammetric analysis of drone-captured stream channel photography. Our test study was conducted on Proctor Creek, a highly responsive urban stream in Atlanta, Georgia, within the crystalline Piedmont region of the southeastern United States. As a baseline, we performed traditional high-precision survey methods to collect morphological measurements (e.g., bankfull and wetted width, bankfull and wetted thalweg depth) at 11 evenly-spaced transects, following USGS protocols along reaches of 20 times average channel width. We additionally used the drone to capture 200+ photos along the same reaches, concurrent with the channel survey. Using the photogrammetry software, we generated georeferenced 3D models of the stream channel, from which morphological measurements were derived from the 11 transects and compared with measurements from the traditional survey method. We additionally explored possibilities for novel morphometric characterization available from the continuous 3D surface, as an improvement on the limited number of detailed cross-sections available from standard methods. These results showed great promise for the drone photogrammetry methods, which encouraged the exploration of the possibility of repeat aerial surveys to evaluate channel response to high flow events. Repeat drone surveys were performed following a sequence of high-flow events in Proctor Creek to evaluate the possibility of using these methods for assessment of stream channel response to flooding.

A rapid method to characterize seabed habitats and associated macro-organisms

USGS Publications Warehouse

Anderson, T.J.; Cochrane, G.R.; Roberts, D.A.; Chezar, H.; Hatcher, G.; ,

2007-01-01

This study presents a method for rapidly collecting, processing, and interrogating real-time abiotic and biotic seabed data to determine seabed habitat classifications. This is done from data collected over a large area of an acoustically derived seabed map, along multidirectional transects, using a towed small camera-sled. The seabed, within the newly designated Point Harris Marine Reserve on the northern coast of San Miguel Island, California, was acoustically imaged using sidescan sonar then ground-truthed using a towed small camera-sled. Seabed characterizations were made from video observations, and were logged to a laptop computer (PC) in real time. To ground-truth the acoustic mosaic, and to characterize abiotic and biotic aspects of the seabed, a three-tiered characterization scheme was employed that described the substratum type, physical structure (i.e., bedform or vertical relief), and the occurrence of benthic macrofauna and flora. A crucial advantage of the method described here, is that preliminary seabed characterizations can be interrogated and mapped over the sidescan mosaic and other seabed information within hours of data collection. This ability to rapidly process seabed data is invaluable to scientists and managers, particularly in modifying concurrent or planning subsequent surveys.

Locating waterfowl observations on aerial surveys

USGS Publications Warehouse

Butler, W.I.; Hodges, J.I.; Stehn, R.A.

1995-01-01

We modified standard aerial survey data collection to obtain the geographic location for each waterfowl observation on surveys in Alaska during 1987-1993. Using transect navigation with CPS (global positioning system), data recording on continuously running tapes, and a computer data input program, we located observations with an average deviation along transects of 214 m. The method provided flexibility in survey design and data analysis. Although developed for geese nesting near the coast of the Yukon-Kuskokwim Delta, the methods are widely applicable and were used on other waterfowl surveys in Alaska to map distribution and relative abundance of waterfowl. Accurate location data with GIS analysis and display may improve precision and usefulness of data from any aerial transect survey.

Distribution and spatial variation of hydrothermal faunal assemblages at Lucky Strike (Mid-Atlantic Ridge) revealed by high-resolution video image analysis

NASA Astrophysics Data System (ADS)

Cuvelier, Daphne; Sarrazin, Jozée; Colaço, Ana; Copley, Jon; Desbruyères, Daniel; Glover, Adrian G.; Tyler, Paul; Serrão Santos, Ricardo

2009-11-01

Whilst the fauna inhabiting hydrothermal vent structures in the Atlantic Ocean is reasonably well known, less is understood about the spatial distributions of the fauna in relation to abiotic and biotic factors. In this study, a major active hydrothermal edifice (Eiffel Tower, at 1690 m depth) on the Lucky Strike vent field (Mid-Atlantic Ridge (MAR)) was investigated. Video transects were carried out by ROV Victor 6000 and complete image coverage was acquired. Four distinct assemblages, ranging from dense larger-sized Bathymodiolus mussel beds to smaller-sized mussel clumps and alvinocaridid shrimps, and two types of substrata were defined based on high definition photographs and video imagery. To evaluate spatial variation, faunal distribution was mapped in three dimensions. A high degree of patchiness characterizes this 11 m high sulfide structure. The differences observed in assemblage and substratum distribution were related to habitat characteristics (fluid exits, depth and structure orientation). Gradients in community structure were observed, which coincided with an increasing distance from the fluid exits. A biological zonation model for the Eiffel Tower edifice was created in which faunal composition and distribution can be visually explained by the presence/absence of fluid exits.

Environmental Impact of a Submarine Cable: Case Study of the Acoustic Thermometry of Ocean Climate (ATOC)/ Pioneer Seamount Cable

NASA Astrophysics Data System (ADS)

Kogan, I.; Paull, C. K.; Kuhnz, L.; von Thun, S.; Burton, E.; Greene, H. G.; Barry, J. P.

2003-12-01

To better understand the potential impacts of the presence of cables on the seabed, a topic of interest for which little data is published or publicly available, a study of the environmental impacts of the ATOC/Pioneer Seamount cable was conducted. The 95 km long, submarine, coaxial cable extends between Pioneer Seamount and the Pillar Point Air Force Station in Half Moon Bay, California. Approximately two thirds of the cable lies within the Monterey Bay National Marine Sanctuary. The cable is permitted to NOAA- Oceanic and Atmospheric Research for transmitting data from a hydrophone array on Pioneer Seamount to shore. The cable was installed unburied on the seafloor in 1995. The cable path crosses the continental shelf, descends to a maximum depth of 1,933 m, and climbs back upslope to 998 m depth near the crest of Pioneer Seamount. A total of 42 hours of video and 152 push cores were collected in 10 stations along cable and control transects using the ROVs Ventana and Tiburon equipped with cable-tracking tools. The condition of the cable, its effect on the seafloor, and distribution of benthic megafauna and infauna were determined. Video data indicated the nature of interaction between the cable and the seafloor. Rocky nearshore areas, where wave energies are greatest, showed the clearest evidence of impact. Here, evidence of abrasion included frayed and unraveling portions of the cable's armor and vertical grooves in the rock apparently cut by the cable. The greatest incision and armor damage occurred on ledges between spans in irregular rock outcrop areas. Unlike the nearshore rocky region, neither the rocks nor the cable appeared damaged along outcrops on Pioneer Seamount. Multiple loops of slack cable added during a 1997 cable repair operation were found lying flat on the seafloor. Several sharp kinks in the cable were seen at 240 m water depths in an area subjected to intense trawling activity. Most of the cable has become buried with time in sediment substrates on the continental shelf whereas much of the cable remains exposed in sediments at deeper depths. The cable is exposed in rocky environments of the nearshore region and on all of Pioneer Seamount. The main biological features associated with the cable were organisms utilizing the cable as substrate and occasionally as shelter. Considerable care was taken to count megafauna in video transects and macrofauna from the top 5 cm of push cores. Few differences were found between cable and control sites at the 95% confidence level. Anemones Metridium farcimen and Stomphia sp. colonized the cable and were more abundant in cable transects at most soft sediment sites. Coarse extrapolation of the transect data suggest that more than 5,000 M. farcimen may live on the continental shelf portion of the cable. Several other species of anemones living on the cable are common along deeper sections of the cable route. Where the cable was buried, the presence of linear rows of sea anemones proved to be a reliable indicator of the cable's position. Flatfish and rockfish apparently congregate near the cable and were as much as 1 order of magnitude more abundant near the cable at some sites.

Spontaneous regeneration of the corticospinal tract after transection in young rats: a key role of reactive astrocytes in making favorable and unfavorable conditions for regeneration.

PubMed

Iseda, T; Nishio, T; Kawaguchi, S; Yamanoto, M; Kawasaki, T; Wakisaka, S

2004-01-01

We demonstrated the occurrence of marked regeneration of the corticospinal tract (CST) after a single transection and failure of regeneration after a repeated transection in young rats. To provide convincing evidence for the complete transection and regeneration we used retrograde neuronal double labeling. Double-labeled neurons that took up the first tracer from the transection site and the second tracer from the injection site caudal to the transection site were observed in the sensorimotor cortex. The anterograde tracing method revealed various patterns of regeneration. In the most successful cases the vast majority of regenerated fibers descended in the normal tract and terminated normally whereas a trace amount of fibers coursed aberrantly. In the less successful cases fibers descended partly normally and partly aberrantly or totally aberrantly. To clarify the role of astrocytes in determining the success or failure of regeneration we compared expression of glial fibrillary acidic protein (GFAP), vimentin and neurofilament (NF) immunoreactivity (IR) in the lesion between single and repeated transections. In either transection, astrocytes disappeared from the CST near the lesion site as early as 3 h after lesioning. However, by 24 h after a single transection, immature astrocytes coexpressing GFAP- and vimentin-IR appeared in the former astrocyte-free area and NF-positive axons crossed the lesion. By contrast, after a repeated transection the astrocyte-free area spread and NF-positive axons never crossed the lesion. It appears likely that the major sign, and possibly cause of failure of regeneration is the prolonged disappearance of astrocytes in the lesioned tract area. Copyright 2004 IBRO

Automated Generation of Geo-Referenced Mosaics From Video Data Collected by Deep-Submergence Vehicles: Preliminary Results

NASA Astrophysics Data System (ADS)

Rhzanov, Y.; Beaulieu, S.; Soule, S. A.; Shank, T.; Fornari, D.; Mayer, L. A.

2005-12-01

Many advances in understanding geologic, tectonic, biologic, and sedimentologic processes in the deep ocean are facilitated by direct observation of the seafloor. However, making such observations is both difficult and expensive. Optical systems (e.g., video, still camera, or direct observation) will always be constrained by the severe attenuation of light in the deep ocean, limiting the field of view to distances that are typically less than 10 meters. Acoustic systems can 'see' much larger areas, but at the cost of spatial resolution. Ultimately, scientists want to study and observe deep-sea processes in the same way we do land-based phenomena so that the spatial distribution and juxtaposition of processes and features can be resolved. We have begun development of algorithms that will, in near real-time, generate mosaics from video collected by deep-submergence vehicles. Mosaics consist of >>10 video frames and can cover 100's of square-meters. This work builds on a publicly available still and video mosaicking software package developed by Rzhanov and Mayer. Here we present the results of initial tests of data collection methodologies (e.g., transects across the seafloor and panoramas across features of interest), algorithm application, and GIS integration conducted during a recent cruise to the Eastern Galapagos Spreading Center (0 deg N, 86 deg W). We have developed a GIS database for the region that will act as a means to access and display mosaics within a geospatially-referenced framework. We have constructed numerous mosaics using both video and still imagery and assessed the quality of the mosaics (including registration errors) under different lighting conditions and with different navigation procedures. We have begun to develop algorithms for efficient and timely mosaicking of collected video as well as integration with navigation data for georeferencing the mosaics. Initial results indicate that operators must be properly versed in the control of the video systems as well as maintaining vehicle attitude and altitude in order to achieve the best results possible.

Application of the AMBUR R package for spatio-temporal analysis of shoreline change: Jekyll Island, Georgia, USA

NASA Astrophysics Data System (ADS)

Jackson, Chester W.; Alexander, Clark R.; Bush, David M.

2012-04-01

The AMBUR (Analyzing Moving Boundaries Using R) package for the R software environment provides a collection of functions for assisting with analyzing and visualizing historical shoreline change. The package allows import and export of geospatial data in ESRI shapefile format, which is compatible with most commercial and open-source GIS software. The "baseline and transect" method is the primary technique used to quantify distances and rates of shoreline movement, and to detect classification changes across time. Along with the traditional "perpendicular" transect method, two new transect methods, "near" and "filtered," assist with quantifying changes along curved shorelines that are problematic for perpendicular transect methods. Output from the analyses includes data tables, graphics, and geospatial data, which are useful in rapidly assessing trends and potential errors in the dataset. A forecasting function also allows the user to estimate the future location of the shoreline and store the results in a shapefile. Other utilities and tools provided in the package assist with preparing and manipulating geospatial data, error checking, and generating supporting graphics and shapefiles. The package can be customized to perform additional statistical, graphical, and geospatial functions, and, it is capable of analyzing the movement of any boundary (e.g., shorelines, glacier terminus, fire edge, and marine and terrestrial ecozones).

Benthic megafaunal community structure of cobalt-rich manganese crusts on Necker Ridge

NASA Astrophysics Data System (ADS)

Morgan, Nicole B.; Cairns, Stephen; Reiswig, Henry; Baco, Amy R.

2015-10-01

In the North Pacific Ocean, the seamounts of the Hawaiian Archipelago and the Mid-Pacific Mountains are connected by Necker Ridge, a 600 km-long feature spanning a depth range of 1400-4000 m. The Necker Ridge is a part of a large area of the central and western Pacific under consideration for cobalt-rich manganese crust mining. We describe the fauna and community structure of the previously unsampled Necker Ridge based on explorations with the submersible Pisces IV. On five pinnacles and a portion of the Ridge ranging from 1400 to 2000 m deep, 27 transects were recorded using HD video, and voucher specimens were collected to aid in species identification. The video was analyzed to identify and count the megafauna found on each transect and to characterize the substrate. Diversity increased from south to north along the feature. There was a significant difference in community structure between southern and northern pinnacles, with southern pinnacles dominated by crinoids of the Family Charitometridae and northern pinnacles dominated by octocorals, especially the Families Isididae and Chrysogorgiidae. DistLM demonstrated a correlation between community structure on the pinnacles and at least six environmental variables, including latitude, sediment cover, and oxygen concentration, but not including depth. The discontinuous and patchy nature of these distinct megafaunal communities highlights growing evidence that cobalt-rich seamounts are highly heterogeneous habitats, and that managing seamounts may require more complex regulations than treating them as a single ecological unit. These results suggest that extensive community analysis should occur at a given site to determine management priority areas, prior to consideration of that site for exploitation of natural resources.

Probable errors in width distributions of sea ice leads measured along a transect

NASA Technical Reports Server (NTRS)

Key, J.; Peckham, S.

1991-01-01

The degree of error expected in the measurement of widths of sea ice leads along a single transect are examined in a probabilistic sense under assumed orientation and width distributions, where both isotropic and anisotropic lead orientations are examined. Methods are developed for estimating the distribution of 'actual' widths (measured perpendicular to the local lead orientation) knowing the 'apparent' width distribution (measured along the transect), and vice versa. The distribution of errors, defined as the difference between the actual and apparent lead width, can be estimated from the two width distributions, and all moments of this distribution can be determined. The problem is illustrated with Landsat imagery and the procedure is applied to a submarine sonar transect. Results are determined for a range of geometries, and indicate the importance of orientation information if data sampled along a transect are to be used for the description of lead geometries. While the application here is to sea ice leads, the methodology can be applied to measurements of any linear feature.

Quantitative US Elastography Can Be Used to Quantify Mechanical and Histologic Tendon Healing in a Rabbit Model of Achilles Tendon Transection.

PubMed

Yamamoto, Yohei; Yamaguchi, Satoshi; Sasho, Takahisa; Fukawa, Taisuke; Akatsu, Yorikazu; Akagi, Ryuichiro; Yamaguchi, Tadashi; Takahashi, Kenji; Nagashima, Kengo; Takahashi, Kazuhisa

2017-05-01

Purpose To determine the time-dependent change in strain ratios (SRs) at the healing site of an Achilles tendon rupture in a rabbit model of tendon transection and to assess the correlation between SRs and the mechanical and histologic properties of the healing tissue. Materials and Methods Experimental methods were approved by the institutional animal care and use committee. The Achilles tendons of 24 New Zealand white rabbits (48 limbs) were surgically transected. The SRs of Achilles tendons were calculated by using compression-based quantitative ultrasonographic elastography measurements obtained 2, 4, 8, and 12 weeks after transection. After in vivo elastography, the left Achilles tendon was harvested for mechanical testing of ultimate load, ultimate stress, elastic modulus, and linear stiffness, and the right tendons were harvested for tissue histologic analysis with the Bonar scale. Time-dependent changes in SRs, mechanical parameters, and Bonar scale scores were evaluated by using repeated-measures analysis of variance. The correlation between SRs and each measured variable was evaluated by using the Spearman rank correlation coefficient. Results Mean SRs and Bonar scale values decreased as a function of time after transection, whereas mechanical parameters increased (P < .001). SR correlated with ultimate stress (ρ = 0.68, P <.001,) elastic modulus (ρ = 0.74, P <.001), and the Bonar scale (ρ = 0.87, P <.001). Conclusion Quantitative elastography could be a useful method with which to evaluate mechanical and histologic properties of the healing tendon. © RSNA, 2017 Online supplemental material is available for this article.

Rectal transection using a curved cutter stapler with an endo-Satinsky clamp during a laparoscopic low anterior resection.

PubMed

Hotta, Tsukasa; Takifuji, Katsunari; Yokoyama, Shozo; Matsuda, Kenji; Yamaue, Hiroki

2012-10-01

A new rectal transaction method was developed using a combination of the curved cutter stapler and endo-Satinsky clamp because of the difficulty in performing rectal transection in the narrow pelvic cavity. The endo-Satinsky clamp is inserted without a flexible trocar cannula by connecting the handle extra-abdominally with a shaft of the endo-Satinsky clamp through the left higher quadrant port via a retrograde course from a midline incision above the pubis symphysis. The endo-Satinsky clamp is used to clamp the rectal wall horizontally at the distal end of the tumor. The wrist of an elastic surgical glove fixed with the shaft of the curved cutter stapler is covered with a midline incision, and consequently, the stapler is inserted into the pelvic cavity. The curved head of the stapler is rotated to the left at the anal side of the endo-Satinsky clamp to insert the rectum between the jaws of the stapler. The stapler is closed and fired, and a rectal transection is thus performed with one firing using a single cartridge. This method was performed in 12 patients with rectal cancer. The median value and range of the tumor distance from the anal verge were 7.0 and 4.5-11.0 cm, respectively. The median duration of the operation was 252 min, and the median blood loss was 15 mL. Only one stapling cartridge was used for rectal transection in all cases, and no major complications were observed. We herein demonstrated a new transection method for rectal cancer.

Effect of Chorda Tympani Nerve Transection on Salt Taste Perception in Mice

PubMed Central

Ishiwatari, Yutaka; Theodorides, Maria L.; Bachmanov, Alexander A.

2011-01-01

Effects of gustatory nerve transection on salt taste have been studied extensively in rats and hamsters but have not been well explored in the mouse. We examined the effects of chorda tympani (CT) nerve transection on NaCl taste preferences and thresholds in outbred CD-1 mice using a high-throughput phenotyping method developed in our laboratory. To measure taste thresholds, mice were conditioned by oral self-administration of LiCl or NaCl and then presented with NaCl concentration series in 2-bottle preference tests. LiCl-conditioned and control NaCl-exposed mice were given bilateral transections of the CT nerve (LiCl-CTX, NaCl-CTX) or were left intact as controls (LiCl-CNT, NaCl-CNT). After recovery from surgery, mice received a concentration series of NaCl (0–300 mM) in 48-h 2-bottle tests. CT transection increased NaCl taste thresholds in LiCl-conditioned mice and eliminated avoidance of concentrated NaCl in control NaCl-exposed mice. This demonstrates that in mice, the CT nerve is important for detection and recognition of NaCl taste and is necessary for the normal avoidance of high concentrations of NaCl. The results of this experiment also show that the method of high-throughput phenotyping of salt taste thresholds is suitable for detecting changes in the taste periphery in mouse genetic studies. PMID:21743094

Gait cycle analysis: parameters sensitive for functional evaluation of peripheral nerve recovery in rat hind limbs.

PubMed

Rui, Jing; Runge, M Brett; Spinner, Robert J; Yaszemski, Michael J; Windebank, Anthony J; Wang, Huan

2014-10-01

Video-assisted gait kinetics analysis has been a sensitive method to assess rat sciatic nerve function after injury and repair. However, in conduit repair of sciatic nerve defects, previously reported kinematic measurements failed to be a sensitive indicator because of the inferior recovery and inevitable joint contracture. This study aimed to explore the role of physiotherapy in mitigating joint contracture and to seek motion analysis indices that can sensitively reflect motor function. Data were collected from 26 rats that underwent sciatic nerve transection and conduit repair. Regular postoperative physiotherapy was applied. Parameters regarding step length, phase duration, and ankle angle were acquired and analyzed from video recording of gait kinetics preoperatively and at regular postoperative intervals. Stride length ratio (step length of uninjured foot/step length of injured foot), percent swing of the normal paw (percentage of the total stride duration when the uninjured paw is in the air), propulsion angle (toe-off angle subtracted by midstance angle), and clearance angle (ankle angle change from toe off to midswing) decreased postoperatively comparing with baseline values. The gradual recovery of these measurements had a strong correlation with the post-nerve repair time course. Ankle joint contracture persisted despite rigorous physiotherapy. Parameters acquired from a 2-dimensional motion analysis system, that is, stride length ratio, percent swing of the normal paw, propulsion angle, and clearance angle, could sensitively reflect nerve function impairment and recovery in the rat sciatic nerve conduit repair model despite the existence of joint contractures.

New approaches to high-resolution mapping of marine vertical structures.

PubMed

Robert, Katleen; Huvenne, Veerle A I; Georgiopoulou, Aggeliki; Jones, Daniel O B; Marsh, Leigh; D O Carter, Gareth; Chaumillon, Leo

2017-08-21

Vertical walls in marine environments can harbour high biodiversity and provide natural protection from bottom-trawling activities. However, traditional mapping techniques are usually restricted to down-looking approaches which cannot adequately replicate their 3D structure. We combined sideways-looking multibeam echosounder (MBES) data from an AUV, forward-looking MBES data from ROVs and ROV-acquired videos to examine walls from Rockall Bank and Whittard Canyon, Northeast Atlantic. High-resolution 3D point clouds were extracted from each sonar dataset and structure from motion photogrammetry (SfM) was applied to recreate 3D representations of video transects along the walls. With these reconstructions, it was possible to interact with extensive sections of video footage and precisely position individuals. Terrain variables were derived on scales comparable to those experienced by megabenthic individuals. These were used to show differences in environmental conditions between observed and background locations as well as explain spatial patterns in ecological characteristics. In addition, since the SfM 3D reconstructions retained colours, they were employed to separate and quantify live coral colonies versus dead framework. The combination of these new technologies allows us, for the first time, to map the physical 3D structure of previously inaccessible habitats and demonstrates the complexity and importance of vertical structures.

Field trials of line transect methods applied to estimation of desert tortoise abundance

USGS Publications Warehouse

Anderson, David R.; Burnham, Kenneth P.; Lubow, Bruce C.; Thomas, L. E. N.; Corn, Paul Stephen; Medica, Philip A.; Marlow, R.W.

2001-01-01

We examine the degree to which field observers can meet the assumptions underlying line transect sampling to monitor populations of desert tortoises (Gopherus agassizii). We present the results of 2 field trials using artificial tortoise models in 3 size classes. The trials were conducted on 2 occasions on an area south of Las Vegas, Nevada, where the density of the test population was known. In the first trials, conducted largely by experienced biologists who had been involved in tortoise surveys for many years, the density of adult tortoise models was well estimated (-3.9% bias), while the bias was higher (-20%) for subadult tortoise models. The bias for combined data was -12.0%. The bias was largely attributed to the failure to detect all tortoise models on or near the transect centerline. The second trials were conducted with a group of largely inexperienced student volunteers and used somewhat different searching methods, and the results were similar to the first trials. Estimated combined density of subadult and adult tortoise models had a negative bias (-7.3%), again attributable to failure to detect some models on or near the centerline. Experience in desert tortoise biology, either comparing the first and second trials or in the second trial with 2 experienced biologists versus 16 novices, did not have an apparent effect on the quality of the data or the accuracy of the estimates. Observer training, specific to line transect sampling, and field testing are important components of a reliable survey. Line transect sampling represents a viable method for large-scale monitoring of populations of desert tortoise; however, field protocol must be improved to assure the key assumptions are met.

Mapping coral and sponge habitats on a shelf-depth environment using multibeam sonar and ROV video observations: Learmonth Bank, northern British Columbia, Canada

NASA Astrophysics Data System (ADS)

Neves, Bárbara M.; Du Preez, Cherisse; Edinger, Evan

2014-01-01

Efforts to locate and map deep-water coral and sponge habitats are essential for the effective management and conservation of these vulnerable marine ecosystems. Here we test the applicability of a simple multibeam sonar classification method developed for fjord environments to map the distribution of shelf-depth substrates and gorgonian coral- and sponge-dominated biotopes. The studied area is a shelf-depth feature Learmonth Bank, northern British Columbia, Canada and the method was applied aiming to map primarily non-reef forming coral and sponge biotopes. Aside from producing high-resolution maps (5 m2 raster grid), biotope-substrate associations were also investigated. A multibeam sonar survey yielded bathymetry, acoustic backscatter strength and slope. From benthic video transects recorded by remotely operated vehicles (ROVs) six primary substrate types and twelve biotope categories were identified, defined by the primary sediment and dominant biological structure, respectively. Substrate and biotope maps were produced using a supervised classification mostly based on the inter-quartile range of the acoustic variables for each substrate type and biotope. Twenty-five percent of the video observations were randomly reserved for testing the classification accuracy. The dominant biotope-defining corals were red tree coral Primnoa pacifica and small styasterids, of which Stylaster parageus was common. Demosponges and hexactinellid sponges were frequently observed but no sponge reefs were observed. The substrate classification readily distinguished fine sediment, Sand and Bedrock from the other substrate types, but had greater difficulty distinguishing Bedrock from Boulders and Cobble. The biotope classification accurately identified Gardens (dense aggregations of sponges and corals) and Primnoa-dominated biotopes (67% accuracy), but most other biotopes had lower accuracies. There was a significant correspondence between Learmonth's biotopes and substrate types, with many biotopes strongly associated with only a single substrate type. This strong correspondence allowed substrate types to function as a surrogate for helping to map biotope distributions. Our results add new information on the distribution of corals and sponges at Learmonth Bank, which can be used to guide management at this location.

Evaluation of Scat Deposition Transects versus Radio Telemetry for Developing a Species Distribution Model for a Rare Desert Carnivore, the Kit Fox.

PubMed

Dempsey, Steven J; Gese, Eric M; Kluever, Bryan M; Lonsinger, Robert C; Waits, Lisette P

2015-01-01

Development and evaluation of noninvasive methods for monitoring species distribution and abundance is a growing area of ecological research. While noninvasive methods have the advantage of reduced risk of negative factors associated with capture, comparisons to methods using more traditional invasive sampling is lacking. Historically kit foxes (Vulpes macrotis) occupied the desert and semi-arid regions of southwestern North America. Once the most abundant carnivore in the Great Basin Desert of Utah, the species is now considered rare. In recent decades, attempts have been made to model the environmental variables influencing kit fox distribution. Using noninvasive scat deposition surveys for determination of kit fox presence, we modeled resource selection functions to predict kit fox distribution using three popular techniques (Maxent, fixed-effects, and mixed-effects generalized linear models) and compared these with similar models developed from invasive sampling (telemetry locations from radio-collared foxes). Resource selection functions were developed using a combination of landscape variables including elevation, slope, aspect, vegetation height, and soil type. All models were tested against subsequent scat collections as a method of model validation. We demonstrate the importance of comparing multiple model types for development of resource selection functions used to predict a species distribution, and evaluating the importance of environmental variables on species distribution. All models we examined showed a large effect of elevation on kit fox presence, followed by slope and vegetation height. However, the invasive sampling method (i.e., radio-telemetry) appeared to be better at determining resource selection, and therefore may be more robust in predicting kit fox distribution. In contrast, the distribution maps created from the noninvasive sampling (i.e., scat transects) were significantly different than the invasive method, thus scat transects may be appropriate when used in an occupancy framework to predict species distribution. We concluded that while scat deposition transects may be useful for monitoring kit fox abundance and possibly occupancy, they do not appear to be appropriate for determining resource selection. On our study area, scat transects were biased to roadways, while data collected using radio-telemetry was dictated by movements of the kit foxes themselves. We recommend that future studies applying noninvasive scat sampling should consider a more robust random sampling design across the landscape (e.g., random transects or more complete road coverage) that would then provide a more accurate and unbiased depiction of resource selection useful to predict kit fox distribution.

Benthic macroinvertebrate field sampling effort required to ...

EPA Pesticide Factsheets

This multi-year pilot study evaluated a proposed field method for its effectiveness in the collection of a benthic macroinvertebrate sample adequate for use in the condition assessment of streams and rivers in the Neuquén Province, Argentina. A total of 13 sites, distributed across three rivers, were sampled. At each site, benthic macroinvertebrates were collected at 11 transects. Each sample was processed independently in the field and laboratory. Based on a literature review and resource considerations, the collection of 300 organisms (minimum) at each site was determined to be necessary to support a robust condition assessment, and therefore, selected as the criterion for judging the adequacy of the method. This targeted number of organisms was collected at all sites, at a minimum, when collections from all 11 transects were combined. Subsequent bootstrapping analysis of data was used to estimate whether collecting at fewer transects would reach the minimum target number of organisms for all sites. In a subset of sites, the total number of organisms frequently fell below the target when fewer than 11 transects collections were combined.Site conditions where <300 organisms might be collected are discussed. These preliminary results suggest that the proposed field method results in a sample that is adequate for robust condition assessment of the rivers and streams of interest. When data become available from a broader range of sites, the adequacy of the field

Geological sampling data and benthic biota classification: Buzzards Bay and Vineyard Sound, Massachusetts

USGS Publications Warehouse

Ackerman, Seth D.; Pappal, Adrienne L.; Huntley, Emily C.; Blackwood, Dann S.; Schwab, William C.

2015-01-01

Sea-floor sample collection is an important component of a statewide cooperative mapping effort between the U.S. Geological Survey (USGS) and the Massachusetts Office of Coastal Zone Management (CZM). Sediment grab samples, bottom photographs, and video transects were collected within Vineyard Sound and Buzzards Bay in 2010 aboard the research vesselConnecticut. This report contains sample data and related information, including analyses of surficial-sediment grab samples, locations and images of sea-floor photography, survey lines along which sea-floor video was collected, and a classification of benthic biota observed in sea-floor photographs and based on the Coastal and Marine Ecological Classification Standard (CMECS). These sample data and analyses information are used to verify interpretations of geophysical data and are an essential part of geologic maps of the sea floor. These data also provide a valuable inventory of benthic habitat and resources. Geographic information system (GIS) data, maps, and interpretations, produced through the USGS and CZM mapping cooperative, are intended to aid efforts to manage coastal and marine resources and to provide baseline information for research focused on coastal evolution and environmental change.

Correction for slope in point and transect relascope sampling of downed coarse woody debris

Treesearch

Goran Stahl; Anna Ringvall; Jeffrey H. Gove; Mark J. Ducey

2002-01-01

In this article, the effect of sloping terrain on estimates in point and transect relascope sampling (PRS and TRS, respectively) is studied. With these inventory methods, a wide angle relascope is used either from sample points (PRS) or along survey lines (TRS). Characteristics associated with line-shaped objects on the ground are assessed, e.g., the length or volume...

The Camera-Based Assessment Survey System (C-BASS): A towed camera platform for reef fish abundance surveys and benthic habitat characterization in the Gulf of Mexico

NASA Astrophysics Data System (ADS)

Lembke, Chad; Grasty, Sarah; Silverman, Alex; Broadbent, Heather; Butcher, Steven; Murawski, Steven

2017-12-01

An ongoing challenge for fisheries management is to provide cost-effective and timely estimates of habitat stratified fish densities. Traditional approaches use modified commercial fishing gear (such as trawls and baited hooks) that have biases in species selectivity and may also be inappropriate for deployment in some habitat types. Underwater visual and optical approaches offer the promise of more precise and less biased assessments of relative fish abundance, as well as direct estimates of absolute fish abundance. A number of video-based approaches have been developed and the technology for data acquisition, calibration, and synthesis has been developing rapidly. Beginning in 2012, our group of engineers and researchers at the University of South Florida has been working towards the goal of completing large scale, video-based surveys in the eastern Gulf of Mexico. This paper discusses design considerations and development of a towed camera system for collection of video-based data on commercially and recreationally important reef fishes and benthic habitat on the West Florida Shelf. Factors considered during development included potential habitat types to be assessed, sea-floor bathymetry, vessel support requirements, personnel requirements, and cost-effectiveness of system components. This regional-specific effort has resulted in a towed platform called the Camera-Based Assessment Survey System, or C-BASS, which has proven capable of surveying tens of kilometers of video transects per day and has the ability to cost-effective population estimates of reef fishes and coincident benthic habitat classification.

Low-altitude photographic transects of the Arctic Network of National Park Units and Selawik National Wildlife Refuge, Alaska, July 2013

USGS Publications Warehouse

Marcot, Bruce G.; Jorgenson, M. Torre; DeGange, Anthony R.

2014-01-01

5. A Canon® Rebel 3Ti with a Sigma zoom lens (18–200 mm focal length). The Drift® HD-170 and GoPro® Hero3 cameras were secured to the struts and underwing for nadir (direct downward) imaging. The Panasonic® and Canon® cameras were each hand-held for oblique-angle landscape images, shooting through the airplanes’ windows, targeting both general landscape conditions as well as landscape features of special interest, such as tundra fire scars and landslips. The Drift® and GoPro® cameras each were set for time-lapse photography at 5-second intervals for overlapping coverage. Photographs from all cameras (100 percent .jpg format) were date- and time-synchronized to geographic positioning system waypoints taken during the flights, also at 5-second intervals, providing precise geotagging (latitude-longitude) of all files. All photographs were adjusted for color saturation and gamma, and nadir photographs were corrected for lens distortion for the Drift® and GoPro® cameras’ 170° wide-angle distortion. EXIF (exchangeable image file format) data on camera settings and geotagging were extracted into spreadsheet databases. An additional 1 hour, 20 minutes, and 43 seconds of high-resolution videos were recorded at 60 frames per second with the GoPro® camera along selected transect segments, and also were image-adjusted and corrected for lens distortion. Geotagged locations of 12,395 nadir photographs from the Drift® and GoPro® cameras were overlayed in a geographic information system (ArcMap 10.0) onto a map of 44 ecotypes (land- and water-cover types) of the Arctic Network study area. Presence and area of each ecotype occurring within a geographic information system window centered on the location of each photograph were recorded and included in the spreadsheet databases. All original and adjusted photographs, videos, geographic positioning system flight tracks, and photograph databases are available by contacting ascweb@usgs.gov.

Mass discharge in a tracer plume: Evaluation of the Theissen Polygon Method

PubMed Central

Mackay, Douglas M.; Einarson, Murray D.; Kaiser, Phil M.; Nozawa-Inoue, Mamie; Goyal, Sham; Chakraborty, Irina; Rasa, Ehsan; Scow, Kate M.

2013-01-01

A tracer plume was created within a thin aquifer by injection for 299 days of two adjacent “sub-plumes” to represent one type of plume heterogeneity encountered in practice. The plume was monitored by snapshot sampling of transects of fully screened wells. The mass injection rate and total mass injected were known. Using all wells in each transect (0.77 m well spacing, 1.4 points/m2 sampling density), the Theissen Polygon Method (TPM) yielded apparently accurate mass discharge (Md) estimates at 3 transects for 12 snapshots. When applied to hypothetical sparser transects using subsets of the wells with average spacing and sampling density from 1.55 to 5.39 m and 0.70 to 0.20 points/m2, respectively, the TPM accuracy depended on well spacing and location of the wells in the hypothesized transect with respect to the sub-plumes. Potential error was relatively low when the well spacing was less than the widths of the sub-plumes (> 0.35 points/m2). Potential error increased for well spacing similar to or greater than the sub-plume widths, or when less than 1% of the plume area was sampled. For low density sampling of laterally heterogeneous plumes, small changes in groundwater flow direction can lead to wide fluctuations in Md estimates by the TPM. However, sampling conducted when flow is known or likely to be in a preferred direction can potentially allow more useful comparisons of Md over multiyear time frames, such as required for performance evaluation of natural attenuation or engineered remediation systems. PMID:22324777

A Case Study in the Effectiveness of Marine Protected Areas (MPAs): the Islands of Bonaire and Curacao, Dutch Caribbean

NASA Astrophysics Data System (ADS)

Relles, Noelle J.

The islands of Bonaire and Curacao, Dutch Caribbean, were both mapped along their leeward coasts for dominant coral community and other benthic cover in the early 1980s. This mapping effort offers a unique baseline for comparing changes in the benthic community of the two islands since that time, particularly given the marked differences between the two islands. Bonaire is well-protected and completely surrounded by a marine protected area (MPA), which includes two no-diving marine reserves; additionally, Bonaire's population is only around 15,000. In contrast, the island of Curacao is home to 140,000 inhabitants and marine protection is limited, with a reef area of 600 ha established as a "paper" park (i.e., little enforcement). Video transects collected by SCUBA over the reefs were collected on Bonaire in January of 2008; when compared to data from 1985, coral cover had declined in the shallowest portion of the reef (< 5 m) and was mostly the result of declines in Acropora spp., whereas head corals increased. Transects closest to the no-diving marine reserves showed higher coral cover and diversity than transects located farther from the reserves. Satellite remote sensing techniques were used to create landscape-scale reef maps along the leeward coasts of both islands, which could differentiate areas of high hard coral cover (> 20%), predominantly sand (> 50%) and areas where hard coral and sand were mixed with soft corals, sea whips and marine plants. These modern maps (2007-09) were groundtruthed using the video data collected on Bonaire for accuracy and then compared to the early 1980s maps of the reefs on both islands. Bonaire experienced declines in coral cover overall and the remaining coral was increasingly patchy; however, changes in patch characteristics were not significant over the time period, but status as a marine reserve and the sheltering of the shoreline did appear to buffer against coral loss. Surprisingly, the island of Curacao did not experience a decline in total coral cover, but did become increasingly patchy, significantly more so than Bonaire. The Curacao Underwater Park afforded no additional protection against coral loss or fragmentation than an adjacent unprotected area of reef. The difference between the two islands in coral loss versus fragmentation has the potential for a unique natural experiment to study the effects of habitat fragmentation in the absence of overall habitat loss at the landscape scale. The Bonaire National Marine Park could benefit by restricting visitors to its most frequented dive sites by increasing the cost of entry into a tiered pay system, thus generating more income for education and management of the park, as well as deterring some divers from these overused sites. Satellite remote sensing-derived maps are useful for rapid reef mapping and can be utilized for comparison to ancillary maps created by more traditional methods. Satellite-derived maps can only distinguish benthic habitats coarsely (3-4 habitat classes) and are only as reliable as their source data, they benefit greatly from fieldwork to determine depth, geographic location, and benthic habitat cover in real time.

Statistical methods for identifying and bounding a UXO target area or minefield

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

McKinstry, Craig A.; Pulsipher, Brent A.; Gilbert, Richard O.

2003-09-18

The sampling unit for minefield or UXO area characterization is typically represented by a geographical block or transect swath that lends itself to characterization by geophysical instrumentation such as mobile sensor arrays. New spatially based statistical survey methods and tools, more appropriate for these unique sampling units have been developed and implemented at PNNL (Visual Sample Plan software, ver. 2.0) with support from the US Department of Defense. Though originally developed to support UXO detection and removal efforts, these tools may also be used in current form or adapted to support demining efforts and aid in the development of newmore » sensors and detection technologies by explicitly incorporating both sampling and detection error in performance assessments. These tools may be used to (1) determine transect designs for detecting and bounding target areas of critical size, shape, and density of detectable items of interest with a specified confidence probability, (2) evaluate the probability that target areas of a specified size, shape and density have not been missed by a systematic or meandering transect survey, and (3) support post-removal verification by calculating the number of transects required to achieve a specified confidence probability that no UXO or mines have been missed.« less

Early changes in muscle atrophy and muscle fiber type conversion after spinal cord transection and peripheral nerve transection in rats.

PubMed

Higashino, Kosaku; Matsuura, Tetsuya; Suganuma, Katsuyoshi; Yukata, Kiminori; Nishisho, Toshihiko; Yasui, Natsuo

2013-05-20

Spinal cord transection and peripheral nerve transection cause muscle atrophy and muscle fiber type conversion. It is still unknown how spinal cord transection and peripheral nerve transection each affect the differentiation of muscle fiber type conversion mechanism and muscle atrophy. The aim of our study was to evaluate the difference of muscle weight change, muscle fiber type conversion, and Peroxisome proliferator-activated receptor-γ coactivatior-1α (PGC-1α) expression brought about by spinal cord transection and by peripheral nerve transection. Twenty-four Wistar rats underwent surgery, the control rats underwent a laminectomy; the spinal cord injury group underwent a spinal cord transection; the denervation group underwent a sciatic nerve transection. The rats were harvested of the soleus muscle and the TA muscle at 0 week, 1 week and 2 weeks after surgery. Histological examination was assessed using hematoxylin and eosin (H&E) staining and immunofluorescent staing. Western blot was performed with 3 groups. Both sciatic nerve transection and spinal cord transection caused muscle atrophy with the effect being more severe after sciatic nerve transection. Spinal cord transection caused a reduction in the expression of both sMHC protein and PGC-1α protein in the soleus muscle. On the other hand, sciatic nerve transection produced an increase in expression of sMHC protein and PGC-1α protein in the soleus muscle. The results of the expression of PGC-1α were expected in other words muscle atrophy after sciatic nerve transection is less than after spinal cord transection, however muscle atrophy after sciatic nerve transection was more severe than after spinal cord transection. In the conclusion, spinal cord transection diminished the expression of sMHC protein and PGC-1α protein in the soleus muscle. On the other hand, sciatic nerve transection enhanced the expression of sMHC protein and PGC-1α protein in the soleus muscle.

Accounting for Subgroup Structure in Line-Transect Abundance Estimates of False Killer Whales (Pseudorca crassidens) in Hawaiian Waters

PubMed Central

Bradford, Amanda L.; Forney, Karin A.; Oleson, Erin M.; Barlow, Jay

2014-01-01

For biological populations that form aggregations (or clusters) of individuals, cluster size is an important parameter in line-transect abundance estimation and should be accurately measured. Cluster size in cetaceans has traditionally been represented as the total number of individuals in a group, but group size may be underestimated if group members are spatially diffuse. Groups of false killer whales (Pseudorca crassidens) can comprise numerous subgroups that are dispersed over tens of kilometers, leading to a spatial mismatch between a detected group and the theoretical framework of line-transect analysis. Three stocks of false killer whales are found within the U.S. Exclusive Economic Zone of the Hawaiian Islands (Hawaiian EEZ): an insular main Hawaiian Islands stock, a pelagic stock, and a Northwestern Hawaiian Islands (NWHI) stock. A ship-based line-transect survey of the Hawaiian EEZ was conducted in the summer and fall of 2010, resulting in six systematic-effort visual sightings of pelagic (n = 5) and NWHI (n = 1) false killer whale groups. The maximum number and spatial extent of subgroups per sighting was 18 subgroups and 35 km, respectively. These sightings were combined with data from similar previous surveys and analyzed within the conventional line-transect estimation framework. The detection function, mean cluster size, and encounter rate were estimated separately to appropriately incorporate data collected using different methods. Unlike previous line-transect analyses of cetaceans, subgroups were treated as the analytical cluster instead of groups because subgroups better conform to the specifications of line-transect theory. Bootstrap values (n = 5,000) of the line-transect parameters were randomly combined to estimate the variance of stock-specific abundance estimates. Hawai’i pelagic and NWHI false killer whales were estimated to number 1,552 (CV = 0.66; 95% CI = 479–5,030) and 552 (CV = 1.09; 95% CI = 97–3,123) individuals, respectively. Subgroup structure is an important factor to consider in line-transect analyses of false killer whales and other species with complex grouping patterns. PMID:24587372

Accounting for subgroup structure in line-transect abundance estimates of false killer whales (Pseudorca crassidens) in Hawaiian waters.

PubMed

Bradford, Amanda L; Forney, Karin A; Oleson, Erin M; Barlow, Jay

2014-01-01

For biological populations that form aggregations (or clusters) of individuals, cluster size is an important parameter in line-transect abundance estimation and should be accurately measured. Cluster size in cetaceans has traditionally been represented as the total number of individuals in a group, but group size may be underestimated if group members are spatially diffuse. Groups of false killer whales (Pseudorca crassidens) can comprise numerous subgroups that are dispersed over tens of kilometers, leading to a spatial mismatch between a detected group and the theoretical framework of line-transect analysis. Three stocks of false killer whales are found within the U.S. Exclusive Economic Zone of the Hawaiian Islands (Hawaiian EEZ): an insular main Hawaiian Islands stock, a pelagic stock, and a Northwestern Hawaiian Islands (NWHI) stock. A ship-based line-transect survey of the Hawaiian EEZ was conducted in the summer and fall of 2010, resulting in six systematic-effort visual sightings of pelagic (n = 5) and NWHI (n = 1) false killer whale groups. The maximum number and spatial extent of subgroups per sighting was 18 subgroups and 35 km, respectively. These sightings were combined with data from similar previous surveys and analyzed within the conventional line-transect estimation framework. The detection function, mean cluster size, and encounter rate were estimated separately to appropriately incorporate data collected using different methods. Unlike previous line-transect analyses of cetaceans, subgroups were treated as the analytical cluster instead of groups because subgroups better conform to the specifications of line-transect theory. Bootstrap values (n = 5,000) of the line-transect parameters were randomly combined to estimate the variance of stock-specific abundance estimates. Hawai'i pelagic and NWHI false killer whales were estimated to number 1,552 (CV = 0.66; 95% CI = 479-5,030) and 552 (CV = 1.09; 95% CI = 97-3,123) individuals, respectively. Subgroup structure is an important factor to consider in line-transect analyses of false killer whales and other species with complex grouping patterns.

Expanding biological data standards development processes for US IOOS: visual line transect observing community for mammal, bird, and turtle data

USGS Publications Warehouse

Fornwall, M.; Gisiner, R.; Simmons, S. E.; Moustahfid, Hassan; Canonico, G.; Halpin, P.; Goldstein, P.; Fitch, R.; Weise, M.; Cyr, N.; Palka, D.; Price, J.; Collins, D.

2012-01-01

The US Integrated Ocean Observing System (IOOS) has recently adopted standards for biological core variables in collaboration with the US Geological Survey/Ocean Biogeographic Information System (USGS/OBIS-USA) and other federal and non-federal partners. In this Community White Paper (CWP) we provide a process to bring into IOOS a rich new source of biological observing data, visual line transect surveys, and to establish quality data standards for visual line transect observations, an important source of at-sea bird, turtle and marine mammal observation data. The processes developed through this exercise will be useful for other similar biogeographic observing efforts, such as passive acoustic point and line transect observations, tagged animal data, and mark-recapture (photo-identification) methods. Furthermore, we suggest that the processes developed through this exercise will serve as a catalyst for broadening involvement by the larger marine biological data community within the goals and processes of IOOS.

Water-level, borehole geophysical log, and water-quality data from wells transecting the freshwater/saline-water interface of the San Antonio segment of the Edwards Aquifer, South-Central Texas, 1999-2007

USGS Publications Warehouse

Lambert, Rebecca B.; Hunt, Andrew G.; Stanton, Gregory P.; Nyman, Michael B.

2009-01-01

As a part of a 9-year (1999-2007) study done by the U.S. Geological Survey in cooperation with the San Antonio Water System to improve understanding of the San Antonio segment of the Edwards aquifer, south-central Texas, in and near the freshwater/saline-water transition zone of the aquifer, the U.S. Geological Survey collected water-level, borehole geophysical, and water-quality data during 1999-2007 from 37 wells arranged in nine transects (except for two wells) across the freshwater/saline-water interface of the aquifer. This report presents the data collected and also describes the data-collection, analytical, and quality-assurance methods used. The wells, constructed with casing from land surface into the upper part of the aquifer and completed as open hole in the aquifer, are in Uvalde County (East Uvalde transect), in Medina County (South Medina and Devine wells), in Bexar County (Pitluk, Mission, and San Antonio transects), in Comal and Guadalupe Counties (Tri-County transect), in Comal County (New Braunfels transect), and in Hays County (Fish Hatchery, San Marcos, and Kyle transects). Data collected included continuous water level at 18 wells; fluid electrical conductivity and temperature with depth (fluid profiles) obtained by borehole geophysical logging of 15 wells; discrete (periodic) samples for major ions and trace elements at 36 wells; stable isotopes or stable isotopes and tritium at 27 wells; dissolved gases obtained by pumping (or collecting flow) of 19 wells; and continuous specific conductance and temperature at three of the wells equipped with continuous water-level sensors.

Coral reefs in Saudi Arabia: 3.5 years after the Gulf War oil spill

NASA Astrophysics Data System (ADS)

Vogt, I. P.

1995-11-01

As a consequence of the 1991 Gulf War, 6-8 million barrels of oil were released into the marine environment and a total of 1.12 billion barrels were burned in the Kuwaiti oil fields. In order to detect delayed effects of the Gulf War pollution, six permanent transect lines were placed on Saudi Arabian offshore and inshore reefs. A comparison of three sets of video recordings taken between 1992 and 1994 indicated a significant increase in live coral cover. Therefore, it has been concluded that corals in Saudi Arabia survived the largest oil spill on record remarkably unscathed, with no visible signs of immediate or late effects up to 3.5 years after the Gulf War.

Adaptive kernel function using line transect sampling

NASA Astrophysics Data System (ADS)

Albadareen, Baker; Ismail, Noriszura

2018-04-01

The estimation of f(0) is crucial in the line transect method which is used for estimating population abundance in wildlife survey's. The classical kernel estimator of f(0) has a high negative bias. Our study proposes an adaptation in the kernel function which is shown to be more efficient than the usual kernel estimator. A simulation study is adopted to compare the performance of the proposed estimators with the classical kernel estimators.

The effects of nicotine exposure and PFC transection on the time-frequency distribution of VTA DA neurons' firing activities.

PubMed

Chen, Ting Y; Zhang, Die; Dragomir, Andrei; Akay, Yasemin; Akay, Metin

2011-05-01

We investigated the influence of nicotine exposure and prefrontal cortex (PFC) transections on ventral tegmental areas (VTA) dopamine (DA) neurons' firing activities using a time-frequency method based on the continuous wavelet transform (CWT). Extracellular single-unit neural activity was recorded from DA neurons in the VTA area of rats. One group had their PFC inputs to the VTA intact, while the other group had the inputs to VTA bilaterally transected immediate caudal to the PFC. We hypothesized that the systemic nicotine exposure will significantly change the energy distribution in the recorded neural activity. Additionally, we investigated whether the loss of inputs to the VTA caused by the PFC transection resulted in the cancellation of the nicotine' effect on the neurons' firing patterns. The time-frequency representations of VTA DA neurons firing activity were estimated from the reconstructed firing rate histogram. The energy contents were estimated from three frequency bands, which are known to encompass the significant modes of operation of DA neurons. Our results show that systemic nicotine exposure disrupts the energy distribution in PFC-intact rats. Particularly, there is a significant increase in energy contents of the 1-1.5 Hz frequency band. This corresponds to an observed increase in the firing rate of VTA DA neurons following nicotine exposure. Additionally, our results from PFC-transected rats show that there is no change in the energy distribution of the recordings after systemic nicotine exposure. These results indicate that the PFC plays an important role in affecting the activities of VTA DA neurons and that the CWT is a useful method for monitoring the changes in neural activity patterns in both time and frequency domains.

Statistical and Multifractal Evaluation of Soil Compaction in a Vineyard

NASA Astrophysics Data System (ADS)

Marinho, M.; Raposo, J. R.; Mirás Avalos, J. M.; Paz González, A.

2012-04-01

One of the detrimental effects caused by agricultural machines is soil compaction, which can be defined by an increase in soil bulk density. Soil compaction often has a negative impact on plant growth, since it reduces the macroporosity and soil permeability and increases resistance to penetration. Our research explored the effect of the agricultural machinery on soil when trafficking through a vineyard at a small spatial scale, based on the evaluation of the soil compaction status. The objectives of this study were: i) to quantify soil bulk density along transects following wine row, wheel track and outside track, and, ii) to characterize the variability of the bulk density along these transects using multifractal analysis. The field work was conducted at the experimental farm of EVEGA (Viticulture and Enology Centre of Galicia) located in Ponte San Clodio, Leiro, Orense, Spain. Three parallel transects were marked on positions with contrasting machine traffic effects, i.e. vine row, wheel-track and outside-track. Undisturbed samples were collected in 16 points of each transect, spaced 0.50 m apart, for bulk density determination using the cylinder method. Samples were taken in autumn 2011, after grape harvest. Since soil between vine rows was tilled and homogenized beginning spring 2011, cumulative effects of traffic during the vine growth period could be evaluated. The distribution patterns of soil bulk density were characterized by multifractal analysis carried out by the method of moments. Multifractality was assessed by several indexes derived from the mass exponent, τq, the generalized dimension, Dq, and the singularity spectrum, f(α), curves. Mean soil bulk density values determined for vine row, outside-track and wheel-track transects were 1.212 kg dm-3, 1.259 kg dm-3and 1.582 kg dm-3, respectively. The respective coefficients of variation (CV) for these three transects were 7.76%, 4.82% and 2.03%. Therefore mean bulk density under wheel-track was 30.5% higher than along the vine row. Vine row and outside-track positions showed not significant differences between means. The bulk density of the wheel-track transect also showed the lowest CV. The multifractal spectra of the three transects were asymmetric curves, rather short toward the left and much longer toward the right. The width of the right deviating shaped multifractal spectra was ranked as: wine row > outside-track ≈ wheel-track. Entropy dimension, D1, was 0.998, 0.992 and 0.992 for vine row, outside-track and track transects, respectively. These results show different patterns of variability of bulk density for parallel transects. They also suggest that multifractal parameters may be useful in assessing the variability of other soil properties such as soil particle density, soil porosity or soil water content, at different spatial scales as well. Acknowledgments. This work was funded in part by Spanish Ministry of Science and Innovation (MICINN) in the frame of project CGL2009-13700-C02. Financial support from CAPES/GOV., Brazil, is also acknowledged by Prof. M. Marinho.

Video conference quality assessment based on cooperative sensing of video and audio

NASA Astrophysics Data System (ADS)

Wang, Junxi; Chen, Jialin; Tian, Xin; Zhou, Cheng; Zhou, Zheng; Ye, Lu

2015-12-01

This paper presents a method to video conference quality assessment, which is based on cooperative sensing of video and audio. In this method, a proposed video quality evaluation method is used to assess the video frame quality. The video frame is divided into noise image and filtered image by the bilateral filters. It is similar to the characteristic of human visual, which could also be seen as a low-pass filtering. The audio frames are evaluated by the PEAQ algorithm. The two results are integrated to evaluate the video conference quality. A video conference database is built to test the performance of the proposed method. It could be found that the objective results correlate well with MOS. Then we can conclude that the proposed method is efficiency in assessing video conference quality.

Location and description of transects for ecological studies in floodplain forests of the lower Suwannee River, Florida

USGS Publications Warehouse

Lewis, L.J.; Light, H.M.; Darst, M.R.

2001-01-01

Twelve transects were established in floodplain forests along the lower Suwannee River, Florida, as the principal data collection sites for a comprehensive study conducted by the U.S. Geological Survey and the Suwannee River Water Management District from 1996 to 2001. Data collected along the 12 transects included hydrologic conditions, land-surface elevations, soils, and vegetation of floodplain forests in relation to river flow. Transect locations are marked in the field with permanent markers at approximately 30 meter intervals. Detailed descriptions of the 12 transects and their locations are provided so that they can be used for future ecological studies. Descriptions of the transects include contact information necessary for access to the property on which the transects are located, maps showing transect locations and routes from the nearest city or major road, small scale maps of each transect showing marker locations, latitude and longitude of each marker, compass bearings of each transect line and graphs showing land-surface elevations of the transect with marker locations.

Using video-based observation research methods in primary care health encounters to evaluate complex interactions.

PubMed

Asan, Onur; Montague, Enid

2014-01-01

The purpose of this paper is to describe the use of video-based observation research methods in primary care environment and highlight important methodological considerations and provide practical guidance for primary care and human factors researchers conducting video studies to understand patient-clinician interaction in primary care settings. We reviewed studies in the literature which used video methods in health care research, and we also used our own experience based on the video studies we conducted in primary care settings. This paper highlighted the benefits of using video techniques, such as multi-channel recording and video coding, and compared "unmanned" video recording with the traditional observation method in primary care research. We proposed a list that can be followed step by step to conduct an effective video study in a primary care setting for a given problem. This paper also described obstacles, researchers should anticipate when using video recording methods in future studies. With the new technological improvements, video-based observation research is becoming a promising method in primary care and HFE research. Video recording has been under-utilised as a data collection tool because of confidentiality and privacy issues. However, it has many benefits as opposed to traditional observations, and recent studies using video recording methods have introduced new research areas and approaches.

Using video-based observation research methods in primary care health encounters to evaluate complex interactions

PubMed Central

Asan, Onur; Montague, Enid

2015-01-01

Objective The purpose of this paper is to describe the use of video-based observation research methods in primary care environment and highlight important methodological considerations and provide practical guidance for primary care and human factors researchers conducting video studies to understand patient-clinician interaction in primary care settings. Methods We reviewed studies in the literature which used video methods in health care research and, we also used our own experience based on the video studies we conducted in primary care settings. Results This paper highlighted the benefits of using video techniques such as multi-channel recording and video coding and compared “unmanned” video recording with the traditional observation method in primary care research. We proposed a list, which can be followed step by step to conduct an effective video study in a primary care setting for a given problem. This paper also described obstacles researchers should anticipate when using video recording methods in future studies. Conclusion With the new technological improvements, video-based observation research is becoming a promising method in primary care and HFE research. Video recording has been under-utilized as a data collection tool because of confidentiality and privacy issues. However, it has many benefits as opposed to traditional observations, and recent studies using video recording methods have introduced new research areas and approaches. PMID:25479346

Full-frame video stabilization with motion inpainting.

PubMed

Matsushita, Yasuyuki; Ofek, Eyal; Ge, Weina; Tang, Xiaoou; Shum, Heung-Yeung

2006-07-01

Video stabilization is an important video enhancement technology which aims at removing annoying shaky motion from videos. We propose a practical and robust approach of video stabilization that produces full-frame stabilized videos with good visual quality. While most previous methods end up with producing smaller size stabilized videos, our completion method can produce full-frame videos by naturally filling in missing image parts by locally aligning image data of neighboring frames. To achieve this, motion inpainting is proposed to enforce spatial and temporal consistency of the completion in both static and dynamic image areas. In addition, image quality in the stabilized video is enhanced with a new practical deblurring algorithm. Instead of estimating point spread functions, our method transfers and interpolates sharper image pixels of neighboring frames to increase the sharpness of the frame. The proposed video completion and deblurring methods enabled us to develop a complete video stabilizer which can naturally keep the original image quality in the stabilized videos. The effectiveness of our method is confirmed by extensive experiments over a wide variety of videos.

Comparison of transect sampling and object-oriented image classification methods of urbanizing catchments

NASA Astrophysics Data System (ADS)

Yang, Y.; Tenenbaum, D. E.

2009-12-01

The process of urbanization has major effects on both human and natural systems. In order to monitor these changes and better understand how urban ecological systems work, urban spatial structure and the variation needs to be first quantified at a fine scale. Because the land-use and land-cover (LULC) in urbanizing areas is highly heterogeneous, the classification of urbanizing environments is the most challenging field in remote sensing. Although a pixel-based method is a common way to do classification, the results are not good enough for many research objectives which require more accurate classification data in fine scales. Transect sampling and object-oriented classification methods are more appropriate for urbanizing areas. Tenenbaum used a transect sampling method using a computer-based facility within a widely available commercial GIS in the Glyndon Catchment and the Upper Baismans Run Catchment, Baltimore, Maryland. It was a two-tiered classification system, including a primary level (which includes 7 classes) and a secondary level (which includes 37 categories). The statistical information of LULC was collected. W. Zhou applied an object-oriented method at the parcel level in Gwynn’s Falls Watershed which includes the two previously mentioned catchments and six classes were extracted. The two urbanizing catchments are located in greater Baltimore, Maryland and drain into Chesapeake Bay. In this research, the two different methods are compared for 6 classes (woody, herbaceous, water, ground, pavement and structure). The comparison method uses the segments in the transect method to extract LULC information from the results of the object-oriented method. Classification results were compared in order to evaluate the difference between the two methods. The overall proportions of LULC classes from the two studies show that there is overestimation of structures in the object-oriented method. For the other five classes, the results from the two methods are similar, except for a difference in the proportions of the woody class. The segment to segment comparison shows that the resolution of the light detection and ranging (LIDAR) data used in the object-oriented method does affect the accuracy of the classification. Shadows of trees and structures are still a big problem in the object-oriented method. For classes that make up a small proportion of the catchments, such as water, neither method was capable of detecting them.

Analysis-Preserving Video Microscopy Compression via Correlation and Mathematical Morphology

PubMed Central

Shao, Chong; Zhong, Alfred; Cribb, Jeremy; Osborne, Lukas D.; O’Brien, E. Timothy; Superfine, Richard; Mayer-Patel, Ketan; Taylor, Russell M.

2015-01-01

The large amount video data produced by multi-channel, high-resolution microscopy system drives the need for a new high-performance domain-specific video compression technique. We describe a novel compression method for video microscopy data. The method is based on Pearson's correlation and mathematical morphology. The method makes use of the point-spread function (PSF) in the microscopy video acquisition phase. We compare our method to other lossless compression methods and to lossy JPEG, JPEG2000 and H.264 compression for various kinds of video microscopy data including fluorescence video and brightfield video. We find that for certain data sets, the new method compresses much better than lossless compression with no impact on analysis results. It achieved a best compressed size of 0.77% of the original size, 25× smaller than the best lossless technique (which yields 20% for the same video). The compressed size scales with the video's scientific data content. Further testing showed that existing lossy algorithms greatly impacted data analysis at similar compression sizes. PMID:26435032

A Quantitative, Non-Destructive Methodology for Habitat Characterisation and Benthic Monitoring at Offshore Renewable Energy Developments

PubMed Central

Sheehan, Emma V.; Stevens, Timothy F.; Attrill, Martin J.

2010-01-01

Following governments' policies to tackle global climate change, the development of offshore renewable energy sites is likely to increase substantially over coming years. All such developments interact with the seabed to some degree and so a key need exists for suitable methodology to monitor the impacts of large-scale Marine Renewable Energy Installations (MREIs). Many of these will be situated on mixed or rocky substrata, where conventional methods to characterise the habitat are unsuitable. Traditional destructive sampling is also inappropriate in conservation terms, particularly as safety zones around (MREIs) could function as Marine Protected Areas, with positive benefits for biodiversity. Here we describe a technique developed to effectively monitor the impact of MREIs and report the results of its field testing, enabling large areas to be surveyed accurately and cost-effectively. The methodology is based on a high-definition video camera, plus LED lights and laser scale markers, mounted on a “flying array” that maintains itself above the seabed grounded by a length of chain, thus causing minimal damage. Samples are taken by slow-speed tows of the gear behind a boat (200 m transects). The HD video and randomly selected frame grabs are analysed to quantify species distribution. The equipment was tested over two years in Lyme Bay, UK (25 m depth), then subsequently successfully deployed in demanding conditions at the deep (>50 m) high-energy Wave Hub site off Cornwall, UK, and a potential tidal stream energy site in Guernsey, Channel Islands (1.5 ms−1 current), the first time remote samples from such a habitat have been achieved. The next stage in the monitoring development process is described, involving the use of Remote Operated Vehicles to survey the seabed post-deployment of MREI devices. The complete methodology provides the first quantitative, relatively non-destructive method for monitoring mixed-substrate benthic communities beneath MPAs and MREIs pre- and post-device deployment. PMID:21206748

A quantitative, non-destructive methodology for habitat characterisation and benthic monitoring at offshore renewable energy developments.

PubMed

Sheehan, Emma V; Stevens, Timothy F; Attrill, Martin J

2010-12-29

Following governments' policies to tackle global climate change, the development of offshore renewable energy sites is likely to increase substantially over coming years. All such developments interact with the seabed to some degree and so a key need exists for suitable methodology to monitor the impacts of large-scale Marine Renewable Energy Installations (MREIs). Many of these will be situated on mixed or rocky substrata, where conventional methods to characterise the habitat are unsuitable. Traditional destructive sampling is also inappropriate in conservation terms, particularly as safety zones around (MREIs) could function as Marine Protected Areas, with positive benefits for biodiversity. Here we describe a technique developed to effectively monitor the impact of MREIs and report the results of its field testing, enabling large areas to be surveyed accurately and cost-effectively. The methodology is based on a high-definition video camera, plus LED lights and laser scale markers, mounted on a "flying array" that maintains itself above the seabed grounded by a length of chain, thus causing minimal damage. Samples are taken by slow-speed tows of the gear behind a boat (200 m transects). The HD video and randomly selected frame grabs are analysed to quantify species distribution. The equipment was tested over two years in Lyme Bay, UK (25 m depth), then subsequently successfully deployed in demanding conditions at the deep (>50 m) high-energy Wave Hub site off Cornwall, UK, and a potential tidal stream energy site in Guernsey, Channel Islands (1.5 ms⁻¹ current), the first time remote samples from such a habitat have been achieved. The next stage in the monitoring development process is described, involving the use of Remote Operated Vehicles to survey the seabed post-deployment of MREI devices. The complete methodology provides the first quantitative, relatively non-destructive method for monitoring mixed-substrate benthic communities beneath MPAs and MREIs pre- and post-device deployment.

Statistical Algorithms Accounting for Background Density in the Detection of UXO Target Areas at DoD Munitions Sites

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

Matzke, Brett D.; Wilson, John E.; Hathaway, J.

2008-02-12

Statistically defensible methods are presented for developing geophysical detector sampling plans and analyzing data for munitions response sites where unexploded ordnance (UXO) may exist. Detection methods for identifying areas of elevated anomaly density from background density are shown. Additionally, methods are described which aid in the choice of transect pattern and spacing to assure with degree of confidence that a target area (TA) of specific size, shape, and anomaly density will be identified using the detection methods. Methods for evaluating the sensitivity of designs to variation in certain parameters are also discussed. Methods presented have been incorporated into the Visualmore » Sample Plan (VSP) software (free at http://dqo.pnl.gov/vsp) and demonstrated at multiple sites in the United States. Application examples from actual transect designs and surveys from the previous two years are demonstrated.« less

Portable Airborne Laser System Measures Forest-Canopy Height

NASA Technical Reports Server (NTRS)

Nelson, Ross

2005-01-01

(PALS) is a combination of laser ranging, video imaging, positioning, and data-processing subsystems designed for measuring the heights of forest canopies along linear transects from tens to thousands of kilometers long. Unlike prior laser ranging systems designed to serve the same purpose, the PALS is not restricted to use aboard a single aircraft of a specific type: the PALS fits into two large suitcases that can be carried to any convenient location, and the PALS can be installed in almost any local aircraft for hire, thereby making it possible to sample remote forests at relatively low cost. The initial cost and the cost of repairing the PALS are also lower because the PALS hardware consists mostly of commercial off-the-shelf (COTS) units that can easily be replaced in the field. The COTS units include a laser ranging transceiver, a charge-coupled-device camera that images the laser-illuminated targets, a differential Global Positioning System (dGPS) receiver capable of operation within the Wide Area Augmentation System, a video titler, a video cassette recorder (VCR), and a laptop computer equipped with two serial ports. The VCR and computer are powered by batteries; the other units are powered at 12 VDC from the 28-VDC aircraft power system via a low-pass filter and a voltage converter. The dGPS receiver feeds location and time data, at an update rate of 0.5 Hz, to the video titler and the computer. The laser ranging transceiver, operating at a sampling rate of 2 kHz, feeds its serial range and amplitude data stream to the computer. The analog video signal from the CCD camera is fed into the video titler wherein the signal is annotated with position and time information. The titler then forwards the annotated signal to the VCR for recording on 8-mm tapes. The dGPS and laser range and amplitude serial data streams are processed by software that displays the laser trace and the dGPS information as they are fed into the computer, subsamples the laser range and amplitude data, interleaves the subsampled data with the dGPS information, and records the resulting interleaved data stream.

Nearshore Bathymetric Change Resolved by Depth Inversions, Sonic Altimeters, and In-Situ Surveys

NASA Astrophysics Data System (ADS)

Brodie, K. L.; Palmsten, M. L.; Hesser, T.; Dickhudt, P.; Ladner, H.; Elgar, S.; Raubenheimer, B.; Penko, A.

2016-12-01

Video-based remote sensing of shoaling and breaking surface gravity waves combined with a depth-inversion algorithm, cBathy, may be able to provide bathymetry information with high spatial and temporal resolution in the nearshore (Holman et al., 2013, JGR, Vol 118). Although the accuracy of cBathy has been assessed in low-wave conditions when coincident in-situ surveys are available, it has not been tested for many conditions with significant wave height > 1.5 m. During high wave conditions, the use of linear wave theory in the depth-inversion algorithm may result in estimates of water depth that are too deep. Here, measurements from an in-situ array of sonic altimeters and from frequent watercraft surveys are used to assess the ability of cBathy to estimate the spatio-temporal evolution of the seafloor during a range of wave conditions at a micro-tidal sandy beach in Duck, NC. Observations were collected continuously from 14 October to 01 November 2015 with 8 altimeters in 1.5 to 4 m water depth on 2 cross-shore transects separated by 75 m in the alongshore during waves that ranged from 0.5 to 1.0 m. Nearshore bathymetry was alongshore variable, with a crescentic bar that attached to the shoreline along one transect and was 150 m offshore along the other transect. Sand levels changed by as much as 1 m in some locations. Additional measurements were collected with 3 altimeters on a single cross-shore transect for 6 months, with wave heights from 0.3 to 5.0 m and sand level fluctuations of up to 1 m in a single day. Initial comparisons with surveys show cBathy RMSE and bias are of similar magnitude to prior studies. Although cBathy resolves the large-scale spatial morphology of the sandbar, when Hs > 1.3 m cBathy estimates of the sandbar location are 10 to 50 m onshore of the surveyed location. cBathy uncertainty estimates were a poor representation of actual errors when compared with the surveys. Six-month-long time series of altimeter data will be used to assess cBathy's performance during large wave conditions, and altimeter and survey data will be used to assess the spatial and temporal scales of change that can be resolved with cBathy. Funded by USACE, ASAALT, NRL, and ASD(R&E).

Clinical use of endovenous indocyanine green during rectosigmoid segmental resection for endometriosis.

PubMed

Seracchioli, Renato; Raimondo, Diego; Arena, Alessandro; Zanello, Margherita; Mabrouk, Mohamed

2018-06-01

To describe a new use of endovenous indocyanine green (ICG) to allow real-time visualization of bowel perfusion in women with recto-sigmoid endometriosis who may be candidates for segmental resection. Step-by-step explanation of this method using descriptive text and educational video. Tertiary level referral academic center. A nulliparous 36-year-old woman affected by a large rectal endometriotic nodule was referred for severe dysmenorrhea, dyspareunia, hematochezia, and dyschezia, despite progestinic therapy. An intravenous injection of 1.5 mL solution containing 3.75 mg dose of ICG for intraoperative fluorescence imaging. Evaluation of blood perfusion of bowel and rectal endometriosis nodule. Evaluation of neoanastomosis vascularization after bowel resection. The procedure of endometriosis removal was performed using the daVinciXi surgical platform (Intuitive Surgical, Sunnyvale, CA). After ovarian endometriosis removal and adhesiolysis, we identified the endometriosis nodule on the anterior surface of the rectum. Pararectal, rectovaginal, and retrorectal spaces were dissected with a nerve-sparing technique. Indocyanine green was administered through a peripheral line. A near-infrared camera head enabled vision of the colorant after latency of a few seconds. We observed the ischemic area around the rectal nodule and perfusion areas upstream and downstream from the lesion. We selected the transecting line for rectal resection, taking account of this objective evaluation, beyond the limits of macroscopic disease. After direct mechanical anastomosis, we checked the rectal vascularization with ICG. To the best of our knowledge, this is the first reported use of endovenous ICG during a bowel resection for deep endometriosis. Endovenous ICG is proposed during surgery for rectosigmoid endometriosis to assess the perfusion of the bowel and select the transecting line. With ICG fluorescence imaging, we can objectively evaluate whether blood supply to the anastomosis is adequate. Endovenous ICG for objective vascular assessment is simple and rapid to use, and no complications related to ICG use were recorded. Copyright © 2018 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Selectivity in the Reinnervation of the Lateral Gastrocnemius Muscle after Nerve Repair with Ethyl Cyanoacrylate in the Rat

PubMed Central

Landegren, Thomas; Risling, Mårten; Hammarberg, Henrik; Persson, Jonas K. E.

2011-01-01

There is a need for complementary surgical techniques that enable rapid and reliable primary repair of transected nerves. Previous studies after peripheral nerve transection and repair with synthetic adhesives have demonstrated regeneration to an extent comparable to that of conventional techniques. The aim of this study was to compare two different repair techniques on the selectivity of muscle reinnervation after repair and completed regeneration. We used the cholera toxin B technique of retrograde axonal tracing to evaluate the morphology, the number, and the three-dimensional location of α-motoneurons innervating the lateral gastrocnemius muscle and compared the results after repair with either ethyl cyanoacrylate (ECA) or epineural sutures of the transected parent sciatic nerve. In addition, we recorded the wet weight of the muscle. Six months after transection and repair of the sciatic nerve, the redistribution of the motoneuron pool was markedly disorganized, the motoneurons had apparently increased in number, and they were scattered throughout a larger volume of the spinal cord gray matter with a decrease in the synaptic coverage compared to controls. A reduction in muscle weight was observed as well. No difference in morphometric variables or muscle weight between the two repair methods could be detected. We conclude that the selectivity of motor reinnervation following sciatic nerve transection and subsequent repair with ECA is comparable to that following conventional micro suturing. PMID:21577248

Critical habitat for ovigerous Dungeness crabs

USGS Publications Warehouse

Scheding, Karen; Shirley, Thomas C.; O'Clair, Charles E.; Taggart, S. James; Kruse, Gordon H.; Bez, Nicolas; Booth, Anthony; Dorn, Martin W.; Hills, Susan; Lipcius, Romuald N.; Pelletier, Dominique; Roy, Claude; Smith, Stephen J.; Witherell, David B.

2001-01-01

The Dungeness crab, Cancer magister, supports an important fishery in the northeastern Pacific Ocean, yet there is limited knowledge of ovigerous female brooding locations and brooding behavior. Our earlier research suggests that ovigerous crabs aggregate at the same brooding locations for many years. Within these locations, ovigerous females occur in high densities, with the majority of the aggregation buried within the sediment. These locations often have similar water depths and sediment types and appear to be critical for this life history stage. Our study was designed to examine the bathymetric distribution of Dungeness crabs in bays with and without sea otters at eight locations within the Glacier Bay area by conducting transects with a video-equipped manned submersible. Two of the bays investigated contained large aggregations of ovigerous females. At both sites the substrate was composed primarily of sand. However, only a small percentage of the 33 km of transects were classified as sand. These data suggest that sand substrate may be a limiting resource. Since crab brooding aggregations represent a large portion of the crab population within a small area, and because they are a critical component of Dungeness life history, areas with these characteristics need to be investigated, mapped, and protected from development or exploitation. The areas requiring protection from the impact of anthropogenic wastes, fishing, and logging activities could be quite small, thus limiting conflict with alternative users.

A method of mobile video transmission based on J2ee

NASA Astrophysics Data System (ADS)

Guo, Jian-xin; Zhao, Ji-chun; Gong, Jing; Chun, Yang

2013-03-01

As 3G (3rd-generation) networks evolve worldwide, the rising demand for mobile video services and the enormous growth of video on the internet is creating major new revenue opportunities for mobile network operators and application developers. The text introduced a method of mobile video transmission based on J2ME, giving the method of video compressing, then describing the video compressing standard, and then describing the software design. The proposed mobile video method based on J2EE is a typical mobile multimedia application, which has a higher availability and a wide range of applications. The users can get the video through terminal devices such as phone.

Comparative population assessments of Nautilus sp. in the Philippines, Australia, Fiji, and American Samoa using baited remote underwater video systems.

PubMed

Barord, Gregory J; Dooley, Frederick; Dunstan, Andrew; Ilano, Anthony; Keister, Karen N; Neumeister, Heike; Preuss, Thomas; Schoepfer, Shane; Ward, Peter D

2014-01-01

The extant species of Nautilus and Allonautilus (Cephalopoda) inhabit fore-reef slope environments across a large geographic area of the tropical western Pacific and eastern Indian Oceans. While many aspects of their biology and behavior are now well-documented, uncertainties concerning their current populations and ecological role in the deeper, fore-reef slope environments remain. Given the historical to current day presence of nautilus fisheries at various locales across the Pacific and Indian Oceans, a comparative assessment of the current state of nautilus populations is critical to determine whether conservation measures are warranted. We used baited remote underwater video systems (BRUVS) to make quantitative photographic records as a means of estimating population abundance of Nautilus sp. at sites in the Philippine Islands, American Samoa, Fiji, and along an approximately 125 km transect on the fore reef slope of the Great Barrier Reef from east of Cairns to east of Lizard Island, Australia. Each site was selected based on its geography, historical abundance, and the presence (Philippines) or absence (other sites) of Nautilus fisheries The results from these observations indicate that there are significantly fewer nautiluses observable with this method in the Philippine Islands site. While there may be multiple possibilities for this difference, the most parsimonious is that the Philippine Islands population has been reduced due to fishing. When compared to historical trap records from the same site the data suggest there have been far more nautiluses at this site in the past. The BRUVS proved to be a valuable tool to measure Nautilus abundance in the deep sea (300-400 m) while reducing our overall footprint on the environment.

A low delay transmission method of multi-channel video based on FPGA

NASA Astrophysics Data System (ADS)

Fu, Weijian; Wei, Baozhi; Li, Xiaobin; Wang, Quan; Hu, Xiaofei

2018-03-01

In order to guarantee the fluency of multi-channel video transmission in video monitoring scenarios, we designed a kind of video format conversion method based on FPGA and its DMA scheduling for video data, reduces the overall video transmission delay.In order to sace the time in the conversion process, the parallel ability of FPGA is used to video format conversion. In order to improve the direct memory access (DMA) writing transmission rate of PCIe bus, a DMA scheduling method based on asynchronous command buffer is proposed. The experimental results show that this paper designs a low delay transmission method based on FPGA, which increases the DMA writing transmission rate by 34% compared with the existing method, and then the video overall delay is reduced to 23.6ms.

Action recognition in depth video from RGB perspective: A knowledge transfer manner

NASA Astrophysics Data System (ADS)

Chen, Jun; Xiao, Yang; Cao, Zhiguo; Fang, Zhiwen

2018-03-01

Different video modal for human action recognition has becoming a highly promising trend in the video analysis. In this paper, we propose a method for human action recognition from RGB video to Depth video using domain adaptation, where we use learned feature from RGB videos to do action recognition for depth videos. More specifically, we make three steps for solving this problem in this paper. First, different from image, video is more complex as it has both spatial and temporal information, in order to better encode this information, dynamic image method is used to represent each RGB or Depth video to one image, based on this, most methods for extracting feature in image can be used in video. Secondly, as video can be represented as image, so standard CNN model can be used for training and testing for videos, beside, CNN model can be also used for feature extracting as its powerful feature expressing ability. Thirdly, as RGB videos and Depth videos are belong to two different domains, in order to make two different feature domains has more similarity, domain adaptation is firstly used for solving this problem between RGB and Depth video, based on this, the learned feature from RGB video model can be directly used for Depth video classification. We evaluate the proposed method on one complex RGB-D action dataset (NTU RGB-D), and our method can have more than 2% accuracy improvement using domain adaptation from RGB to Depth action recognition.

An unsupervised method for summarizing egocentric sport videos

NASA Astrophysics Data System (ADS)

Habibi Aghdam, Hamed; Jahani Heravi, Elnaz; Puig, Domenec

2015-12-01

People are getting more interested to record their sport activities using head-worn or hand-held cameras. This type of videos which is called egocentric sport videos has different motion and appearance patterns compared with life-logging videos. While a life-logging video can be defined in terms of well-defined human-object interactions, notwithstanding, it is not trivial to describe egocentric sport videos using well-defined activities. For this reason, summarizing egocentric sport videos based on human-object interaction might fail to produce meaningful results. In this paper, we propose an unsupervised method for summarizing egocentric videos by identifying the key-frames of the video. Our method utilizes both appearance and motion information and it automatically finds the number of the key-frames. Our blind user study on the new dataset collected from YouTube shows that in 93:5% cases, the users choose the proposed method as their first video summary choice. In addition, our method is within the top 2 choices of the users in 99% of studies.

Marine tunicates from Sangkarang Archipelago Indonesia: recent finding and bio-prospecting

NASA Astrophysics Data System (ADS)

Litaay, Magdalena

2018-03-01

Tunicate belongs to urochordata that inhabit benthic area of coral reefs. This paper attempts to compile result of several studies on diversity of marine tunicates from Sangkarang Archipelago of South Sulawesi Indonesia. Method for tunicates sample collection was line transect method that applied at two 3 and 7 m depth. A 50 m line transect was applied parallel to a shore line in each depth and was done in duplicate. A 2.5 m plot was places side by side of transect, in which all tunicate inside plot was counted, identified, and photographed, respectively. Tunicates identification was based on morphological characteristics. The latest finding shows that eighteen species of tunicates were recorded in Samalona waters as also the same number of species in Barrang Caddi waters. The result from this finding was compared to previous studies done at other part of Sangkarang area. This study concluded that this archipelago is rich in tunicates and these resources can be utilized for various purposes. Bioprospect of marine tunicates is also discus in the present study.

Comparison of Relative Bias, Precision, and Efficiency of Sampling Methods for Natural Enemies of Soybean Aphid (Hemiptera: Aphididae).

PubMed

Bannerman, J A; Costamagna, A C; McCornack, B P; Ragsdale, D W

2015-06-01

Generalist natural enemies play an important role in controlling soybean aphid, Aphis glycines (Hemiptera: Aphididae), in North America. Several sampling methods are used to monitor natural enemy populations in soybean, but there has been little work investigating their relative bias, precision, and efficiency. We compare five sampling methods: quadrats, whole-plant counts, sweep-netting, walking transects, and yellow sticky cards to determine the most practical methods for sampling the three most prominent species, which included Harmonia axyridis (Pallas), Coccinella septempunctata L. (Coleoptera: Coccinellidae), and Orius insidiosus (Say) (Hemiptera: Anthocoridae). We show an important time by sampling method interaction indicated by diverging community similarities within and between sampling methods as the growing season progressed. Similarly, correlations between sampling methods for the three most abundant species over multiple time periods indicated differences in relative bias between sampling methods and suggests that bias is not consistent throughout the growing season, particularly for sticky cards and whole-plant samples. Furthermore, we show that sticky cards produce strongly biased capture rates relative to the other four sampling methods. Precision and efficiency differed between sampling methods and sticky cards produced the most precise (but highly biased) results for adult natural enemies, while walking transects and whole-plant counts were the most efficient methods for detecting coccinellids and O. insidiosus, respectively. Based on bias, precision, and efficiency considerations, the most practical sampling methods for monitoring in soybean include walking transects for coccinellid detection and whole-plant counts for detection of small predators like O. insidiosus. Sweep-netting and quadrat samples are also useful for some applications, when efficiency is not paramount. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Recovery of Benthic Megafauna from Anthropogenic Disturbance at a Hydrocarbon Drilling Well (380 m Depth in the Norwegian Sea)

PubMed Central

Gates, Andrew R.; Jones, Daniel O. B.

2012-01-01

Recovery from disturbance in deep water is poorly understood, but as anthropogenic impacts increase in deeper water it is important to quantify the process. Exploratory hydrocarbon drilling causes physical disturbance, smothering the seabed near the well. Video transects obtained by remotely operated vehicles were used to assess the change in invertebrate megafaunal density and diversity caused by drilling a well at 380 m depth in the Norwegian Sea in 2006. Transects were carried out one day before drilling commenced and 27 days, 76 days, and three years later. A background survey, further from the well, was also carried out in 2009. Porifera (45% of observations) and Cnidaria (40%) dominated the megafauna. Porifera accounted for 94% of hard-substratum organisms and cnidarians (Pennatulacea) dominated on the soft sediment (78%). Twenty seven and 76 days after drilling commenced, drill cuttings were visible, extending over 100 m from the well. In this area there were low invertebrate megafaunal densities (0.08 and 0.10 individuals m−2) in comparison to pre-drill conditions (0.21 individuals m−2). Three years later the visible extent of the cuttings had reduced, reaching 60 m from the well. Within this area the megafaunal density (0.05 individuals m−2) was lower than pre-drill and reference transects (0.23 individuals m−2). There was a significant increase in total megafaunal invertebrate densities with both distance from drilling and time since drilling although no significant interaction. Beyond the visible disturbance there were similar megafaunal densities (0.14 individuals m−2) to pre-drilling and background surveys. Species richness, Shannon-Weiner diversity and multivariate techniques showed similar patterns to density. At this site the effects of exploratory drilling on megafaunal invertebrate density and diversity seem confined to the extent of the visible cuttings pile. However, elevated Barium concentration and reduced sediment grain size suggest persistence of disturbance for three years, with unclear consequences for other components of the benthic fauna. PMID:23056177

Electrical Resistivity and Seismic Surveys at the Nevada Test Site, Nevada, April 2007

USGS Publications Warehouse

Haines, Seth S.; Burton, Bethany L.; Sweetkind, Donald S.; Asch, Theodore H.

2008-01-01

In April 2007, the USGS collected direct-current (DC) electrical resistivity data and shear- (S) and compressional- (P) wave seismic data to provide new detail of previously mapped, overlapping fault splays at two administrative areas in the Nevada Test Site (NTS). In NTS Area 7, we collected two-dimensional DC resistivity data along a transect crossing the Yucca Fault parallel to, and between, two transects along which resistivity data were collected in a previous study in 2006. In addition, we collected three-dimensional DC resistivity data in a grid that overlies part of the 2007 transect. The DC resistivity data show that the fault has a footwall that is more conductive than the hanging wall and an along-strike progression of the fault in a location where overlapping splays are present. Co-located with the northernmost of the two 2006 DC resistivity transects, we acquired S- and P-wave seismic data for both reflection and refraction processing. The S-wave data are corrupted by large amounts of converted (P-wave) energy likely due to the abundance of fractured caliche in the shallow subsurface. The P-wave data show minimal reflected energy, but they show clear refracted first arrivals. We have inverted these first arrival times to determine P-wave seismic velocity models. The seismic model for the transect in Area 7 shows low velocities extending to the base of the model at the location of the Yucca Fault, as well as low velocities at the eastern end of the transect, in the vicinity of the adjacent crater. These new surveys provide further detail about the geometry of the Yucca Fault in this location where it shows two overlapping splays. We collected P- and S-wave seismic data along a transect in the southern part of NTS Area 2, corresponding with the location of a 2006 DC resistivity transect that targeted a set of small faults identified with field mapping. Again, the S-wave data are difficult to interpret. The P-wave data show clear first arrivals that we inverted, yielding a velocity model that shows lateral heterogeneity similar to the 2006 DC resistivity models. Finally, we collected P-wave data along a second transect in Area 2, located north of the first line and in an area of a very minor fault that was targeted by another 2006 DC resistivity survey. The P-wave refraction velocity model shows generally high velocities, with a zone of somewhat lower velocities in the central part of the transect. The position of the low velocity zone corresponds with the location of a minor fault, though it is unclear whether the two are related. Together, these results demonstrate the value of geophysical data for mapping the subsurface extent of faults. The 2007 DC resistivity data complement the 2006 data and provide important new detail of the overlapping fault splays. The seismic data demonstrate the ability of P-wave refraction methods to identify the damage zones at faults, and they show the difficulties associated with S-wave methods in areas with caliche. Combining all of the geophysical data from the Area 7 studies, we are able to develop a coherent interpretation of the relation between the site geology, the fault, and the observations.

Simulation of Anterior Cruciate Ligament Deficiency in a Musculoskeletal Model with Anatomical Knees

PubMed Central

Guess, Trent M; Stylianou, Antonis

2012-01-01

Abnormal knee kinematics and meniscus injury resulting from anterior cruciate ligament (ACL) deficiency are often implicated in joint degeneration even though changes in tibio-femoral contact location after injury are small, typically only a few millimeters. Ligament reconstruction surgery does not significantly reduce the incidence of early onset osteoarthritis. Increased knowledge of knee contact mechanics would increase our understanding of the effects of ACL injury and help guide ACL reconstruction methods. Presented here is a cadaver specific computational knee model combined with a body-level musculoskeletal model from a subject of similar height and weight as the cadaver donor. The knee model was developed in the multi-body framework and includes representation of the menisci. Experimental body-level measurements provided input to the musculoskeletal model. The location of tibio-menisco-femoral contact as well as contact pressures were compared for models with an intact ACL, partial ACL transection (posterolateral bundle transection), and full ACL transection during a muscle driven forward dynamics simulation of a dual limb squat. During the squat, small changes in femur motion relative to the tibia for both partial and full ACL transection push the lateral meniscus in the posterior direction at extension. The central-anterior region of the lateral meniscus then becomes “wedged” between the tibia and femur during knee flexion. This “wedging” effect does not occur for the intact knee. Peak contact pressure and contact locations are similar for the partial tear and complete ACL transection during the deep flexion portion of the squat, particularly on the lateral side. The tibio-femoral contact location on the tibia plateau shifts slightly to the posterior and lateral direction with ACL transection. PMID:22470411

Scar modulation in subacute and chronic CNS lesions: Effects on axonal regeneration.

PubMed

Stichel, Christine C.; Lausberg, Friederike; Hermanns, Susanne; Müller, Hans Werner

1999-01-01

After injury of the adult mammalian CNS axonal regeneration across or around the lesion scar is negligible. Previously, we have shown that the lesion-induced basal membrane (BM) within the lesion center participates in a growth barrier for axon regeneration and that its reduction by means of pharmacological or immunochemical treatment is a prerequisite and sufficient condition for regrowing axons to cross the lesion site. The present study was designed to further investigate this observation by analyzing the effect of a delayed treatment on the regeneration of both subacutely and chronically lesioned axons.Adult rats underwent unilateral transection of the postcommissural fornix. At one to five days after transection one group of animals received a local injection of 2, 2'-dipyridyl (DPY), an inhibitor of collagen triple helix formation and synthesis. Another group received a second transection within the former lesion site followed by an immediate DPY-injection at five days or 4 weeks after transection. Six weeks after the last surgery BM deposition and axonal regeneration were analysed using immunocytochemical methods.A local injection of DPY clearly reduced the lesion-induced BM deposition when applied within the first 3 days after transection. Under these conditions regrowing axons still crossed the former impermeable lesion site and regenerated within their normal pathway up to their former target, the mammillary body. However, in late subacute (5 d) and chronic stages (4 w) the double transection+injection paradigm failed to reduce BM deposition and, in consequence, also to induce axonal regeneration.These results demonstrate the potential of the collagen IV-reducing strategy to promote axonal regeneration across the lesion scar not only in acute but also in early subacute traumatic injuries.

Transection Speed and Impact on Perioperative Inflammatory Response – A Randomized Controlled Trial Comparing Stapler Hepatectomy and CUSA Resection

PubMed Central

Schwarz, Christoph; Klaus, Daniel A.; Tudor, Bianca; Fleischmann, Edith; Wekerle, Thomas; Roth, Georg; Bodingbauer, Martin; Kaczirek, Klaus

2015-01-01

Background Parenchymal transection represents a crucial step during liver surgery and many different techniques have been described so far. Stapler resection is supposed to be faster than CUSA resection. However, whether speed impacts on the inflammatory response in patients undergoing liver resection (LR) remains unclear. Materials and Methods This is a randomized controlled trial including 40 patients undergoing anatomical LR. Primary endpoint was transection speed (cm2/min). Secondary endpoints included the perioperative change of pro- and anti-inflammatory cytokines, overall surgery duration, length of hospital stay, morbidity and mortality. Results Mean transection speed was significantly higher in patients undergoing stapler hepatectomy compared to CUSA resection (CUSA: 1 (0.4) cm2/min vs. Stapler: 10.8 (6.1) cm2/min; p<0.0001). Analyzing the impact of surgery duration on inflammatory response revealed a significant correlation between IL-6 levels measured at the end of surgery and the overall length of surgery (p<0.0001, r = 0.6188). Patients undergoing CUSA LR had significantly higher increase of interleukin-6 (IL-6) after parenchymal transection compared to patients with stapler hepatectomy in the portal and hepatic veins, respectively (p = 0.028; p = 0.044). C-reactive protein levels on the first post-operative day were significantly lower in the stapler cohort (p = 0.010). There was a trend towards a reduced overall surgery time in patients with stapler LR, especially in the subgroup of patients undergoing minor hepatectomies (p = 0.020). Conclusions Liver resection using staplers is fast, safe and suggests a diminished inflammatory response probably due to a decreased parenchymal transection time. Trial Registration ClinicalTrials.gov NCT01785212 PMID:26452162

Endovascular repair of thoracic aortic traumatic transections is a safe method in patients with complicated injuries.

PubMed

Rahimi, Saum A; Darling, R Clement; Mehta, Manish; Roddy, Sean P; Taggert, John B; Sternbach, Yaron

2010-10-01

Historically thoracic aortic rupture secondary to trauma was treated with cardiopulmonary bypass and open surgery. With the advent of endovascular grafting, physicians have the ability to reconstruct the thoracic aortic transection using a less invasive technique. In this study, we examine our experience with stent graft repair of thoracic transections secondary to trauma. The medical records of patients treated at a level I trauma center from 2005 to 2008 were reviewed. Those patients who had an aortic transection treated with an endograft were identified and evaluated for in-hospital mortality and morbidity and concurrent injuries. Demographics, procedural details, and outcomes were analyzed. Over a 3-year period, 18 thoracic aortic transections secondary to trauma were identified in patients with a mean age of 43 (range, 16-80). Primary technical success was 100%. None of the patients required explant or open repair during this time period. In-hospital mortality was 2 of 18 (11%); all patients had multiple trauma including long bone fractures. The subclavian artery origin was covered by the stent graft in 9 of the 18 patients. The mean estimated blood loss per procedure was 222 cc. No patient in this series had postoperative paraplegia. Follow-up ranged from 1 to 50 months with an average of 13 months. There have been no late explantation or device failures identified. Endovascular repair of traumatic thoracic aortic transections can be performed safely with a relatively low mortality and morbidity and should be the procedure of choice for patients presenting with traumatic thoracic aortic ruptures. Copyright © 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Hyperexcitability of bladder afferent neurons associated with reduction of Kv1.4 α-subunit in rats with spinal cord injury.

PubMed

Takahashi, Ryosuke; Yoshizawa, Tsuyoshi; Yunoki, Takakazu; Tyagi, Pradeep; Naito, Seiji; de Groat, William C; Yoshimura, Naoki

2013-12-01

To clarify the functional and molecular mechanisms inducing hyperexcitability of C-fiber bladder afferent pathways after spinal cord injury we examined changes in the electrophysiological properties of bladder afferent neurons, focusing especially on voltage-gated K channels. Freshly dissociated L6-S1 dorsal root ganglion neurons were prepared from female spinal intact and spinal transected (T9-T10 transection) Sprague Dawley® rats. Whole cell patch clamp recordings were performed on individual bladder afferent neurons. Kv1.2 and Kv1.4 α-subunit expression levels were also evaluated by immunohistochemical and real-time polymerase chain reaction methods. Capsaicin sensitive bladder afferent neurons from spinal transected rats showed increased cell excitability, as evidenced by lower spike activation thresholds and a tonic firing pattern. The peak density of transient A-type K+ currents in capsaicin sensitive bladder afferent neurons from spinal transected rats was significantly less than that from spinal intact rats. Also, the KA current inactivation curve was displaced to more hyperpolarized levels after spinal transection. The protein and mRNA expression of Kv1.4 α-subunits, which can form transient A-type K+ channels, was decreased in bladder afferent neurons after spinal transection. Results indicate that the excitability of capsaicin sensitive C-fiber bladder afferent neurons is increased in association with reductions in transient A-type K+ current density and Kv1.4 α-subunit expression in injured rats. Thus, the Kv1.4 α-subunit could be a molecular target for treating overactive bladder due to neurogenic detrusor overactivity. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Pitanguy's otoplasty: report of 551 operations.

PubMed

Werdin, Frank; Wolters, Marianne; Lampe, Hermann

2007-01-01

Protruding ears is a common condition and in plastic surgery there are many techniques for correcting them such as suture, transection, and scoring. Over a period of 15 years, we have used Pitanguy's otoplasty. The advantages of the Pitanguy technique have been verified in a retrospective study of 278 patients followed up for up to 15 years. There were 20 relapses (4%), which is clearly lower than the mean (between 8% and 11%) for patients treated by other methods. The main reason for our low rate resulted from the generation of large scarring areas, using a combination of transection and seaming. We think that a slightly modified Pitanguy's method reduces postoperative morbidity which affects the aesthetic results.

Comparison of blood chemistry values for samples collected from juvenile chinook salmon by three methods

USGS Publications Warehouse

Congleton, J.L.; LaVoie, W.J.

2001-01-01

Thirteen blood chemistry indices were compared for samples collected by three commonly used methods: caudal transection, heart puncture, and caudal vessel puncture. Apparent biases in blood chemistry values for samples obtained by caudal transection were consistent with dilution with tissue fluids: alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK), triglyceride, and K+ were increased and Na+ and Cl- were decreased relative to values for samples obtained by caudal vessel puncture. Some enzyme activities (ALT, AST, LDH) and K+ concentrations were also greater in samples taken by heart puncture than in samples taken by caudal vessel puncture. Of the methods tested, caudal vessel puncture had the least effect on blood chemistry values and should be preferred for blood chemistry studies on juvenile salmonids.

Comparing Methods of Assessing Dog Rabies Vaccination Coverage in Rural and Urban Communities in Tanzania

PubMed Central

Sambo, Maganga; Johnson, Paul C. D.; Hotopp, Karen; Changalucha, Joel; Cleaveland, Sarah; Kazwala, Rudovick; Lembo, Tiziana; Lugelo, Ahmed; Lushasi, Kennedy; Maziku, Mathew; Mbunda, Eberhard; Mtema, Zacharia; Sikana, Lwitiko; Townsend, Sunny E.; Hampson, Katie

2017-01-01

Rabies can be eliminated by achieving comprehensive coverage of 70% of domestic dogs during annual mass vaccination campaigns. Estimates of vaccination coverage are, therefore, required to evaluate and manage mass dog vaccination programs; however, there is no specific guidance for the most accurate and efficient methods for estimating coverage in different settings. Here, we compare post-vaccination transects, school-based surveys, and household surveys across 28 districts in southeast Tanzania and Pemba island covering rural, urban, coastal and inland settings, and a range of different livelihoods and religious backgrounds. These approaches were explored in detail in a single district in northwest Tanzania (Serengeti), where their performance was compared with a complete dog population census that also recorded dog vaccination status. Post-vaccination transects involved counting marked (vaccinated) and unmarked (unvaccinated) dogs immediately after campaigns in 2,155 villages (24,721 dogs counted). School-based surveys were administered to 8,587 primary school pupils each representing a unique household, in 119 randomly selected schools approximately 2 months after campaigns. Household surveys were conducted in 160 randomly selected villages (4,488 households) in July/August 2011. Costs to implement these coverage assessments were $12.01, $66.12, and $155.70 per village for post-vaccination transects, school-based, and household surveys, respectively. Simulations were performed to assess the effect of sampling on the precision of coverage estimation. The sampling effort required to obtain reasonably precise estimates of coverage from household surveys is generally very high and probably prohibitively expensive for routine monitoring across large areas, particularly in communities with high human to dog ratios. School-based surveys partially overcame sampling constraints, however, were also costly to obtain reasonably precise estimates of coverage. Post-vaccination transects provided precise and timely estimates of community-level coverage that could be used to troubleshoot the performance of campaigns across large areas. However, transects typically overestimated coverage by around 10%, which therefore needs consideration when evaluating the impacts of campaigns. We discuss the advantages and disadvantages of these different methods and make recommendations for how vaccination campaigns can be better monitored and managed at different stages of rabies control and elimination programs. PMID:28352630

A double-observer method for reducing bias in faecal pellet surveys of forest ungulates

USGS Publications Warehouse

Jenkins, K.J.; Manly, B.F.J.

2008-01-01

1. Faecal surveys are used widely to study variations in abundance and distribution of forest-dwelling mammals when direct enumeration is not feasible. The utility of faecal indices of abundance is limited, however, by observational bias and variation in faecal disappearance rates that obscure their relationship to population size. We developed methods to reduce variability in faecal surveys and improve reliability of faecal indices. 2. We used double-observer transect sampling to estimate observational bias of faecal surveys of Roosevelt elk Cervus elaphus roosevelti and Columbian black-tailed deer Odocoileus hemionus columbianus in Olympic National Park, Washington, USA. We also modelled differences in counts of faecal groups obtained from paired cleared and uncleared transect segments as a means to adjust standing crop faecal counts for a standard accumulation interval and to reduce bias resulting from variable decay rates. 3. Estimated detection probabilities of faecal groups ranged from < 0.2-1.0 depending upon the observer, whether the faecal group was from elk or deer, faecal group size, distance of the faecal group from the sampling transect, ground vegetation cover, and the interaction between faecal group size and distance from the transect. 4. Models of plot-clearing effects indicated that standing crop counts of deer faecal groups required 34% reduction on flat terrain and 53% reduction on sloping terrain to represent faeces accumulated over a standard 100-day interval, whereas counts of elk faecal groups required 0% and 46% reductions on flat and sloping terrain, respectively. 5. Synthesis and applications. Double-observer transect sampling provides a cost-effective means of reducing observational bias and variation in faecal decay rates that obscure the interpretation of faecal indices of large mammal abundance. Given the variation we observed in observational bias of faecal surveys and persistence of faeces, we emphasize the need for future researchers to account for these comparatively manageable sources of bias before comparing faecal indices spatially or temporally. Double-observer sampling methods are readily adaptable to study variations in faecal indices of large mammals at the scale of the large forest reserve, natural area, or other forested regions when direct estimation of populations is problematic. ?? 2008 The Authors.

Ecohydrological optimality in the Northeast China Transect

NASA Astrophysics Data System (ADS)

Cong, Zhentao; Li, Qinshu; Mo, Kangle; Zhang, Lexin; Shen, Hong

2017-05-01

The Northeast China Transect (NECT) is one of the International Geosphere-Biosphere Program (IGBP) terrestrial transects, where there is a significant precipitation gradient from east to west, as well as a vegetation transition of forest-grassland-desert. It is remarkable to understand vegetation distribution and dynamics under climate change in this transect. We take canopy cover (M), derived from Normalized Difference Vegetation Index (NDVI), as an index to describe the properties of vegetation distribution and dynamics in the NECT. In Eagleson's ecohydrological optimality theory, the optimal canopy cover (M*) is determined by the trade-off between water supply depending on water balance and water demand depending on canopy transpiration. We apply Eagleson's ecohydrological optimality method in the NECT based on data from 2000 to 2013 to get M*, which is compared with M from NDVI to further discuss the sensitivity of M* to vegetation properties and climate factors. The result indicates that the average M* fits the actual M well (for forest, M* = 0.822 while M = 0.826; for grassland, M* = 0.353 while M = 0.352; the correlation coefficient between M and M* is 0.81). Results of water balance also match the field-measured data in the references. The sensitivity analyses show that M* decreases with the increase of leaf area index (LAI), stem fraction and temperature, while it increases with the increase of leaf angle and precipitation amount. Eagleson's ecohydrological optimality method offers a quantitative way to understand the impacts of climate change on canopy cover and provides guidelines for ecorestoration projects.

Primary non-transecting bulbar urethroplasty long-term success rates are similar to transecting urethroplasty.

PubMed

Anderson, Kirk M; Blakely, Stephen A; O'Donnell, Colin I; Nikolavsky, Dmitriy; Flynn, Brian J

2017-01-01

To review the long-term outcomes of transecting versus non-transecting urethroplasty to repair bulbar urethral strictures. A retrospective review was conducted of 342 patients who underwent anterior urethroplasty performed by a single surgeon from 2003 to 2014. Patients were excluded from further analysis if there had been prior urethroplasty, stricture location outside the bulbous urethra, or age <18 years. In the transecting group, surgical techniques used included excision and primary anastomosis and augmented anastomotic urethroplasty. In the non-transecting group, surgical techniques used included non-transecting anastomotic urethroplasty and dorsal and/or ventral buccal grafting. The primary endpoint was stricture resolution in transecting vs. non-transecting bulbar urethroplasty. Success was defined as freedom from secondary procedures including dilation, urethrotomy, or repeat urethroplasty. One hundred and fifty-two patients met inclusion criteria. At a mean follow-up of 65 months (range: 10-138 months), stricture-free recurrence in the transecting and non-transecting groups was similar, 83% (n = 85/102) and 82% (n = 41/50), respectively (p = 0.84). Surgical technique (p = 0.91), stricture length (p = 0.8), and etiology (p = 0.6) did not affect stricture recurrence rate on multivariate analysis. There was no difference detected in time to stricture recurrence (p = 0.21). In this retrospective series, transecting and non-transecting primary bulbar urethroplasty resulted in similar long-term stricture resolution rate. Prospective studies are needed to determine what differences may present in outcomes related to sexual function and long-term success.

Objectification of perceptual image quality for mobile video

NASA Astrophysics Data System (ADS)

Lee, Seon-Oh; Sim, Dong-Gyu

2011-06-01

This paper presents an objective video quality evaluation method for quantifying the subjective quality of digital mobile video. The proposed method aims to objectify the subjective quality by extracting edgeness and blockiness parameters. To evaluate the performance of the proposed algorithms, we carried out subjective video quality tests with the double-stimulus continuous quality scale method and obtained differential mean opinion score values for 120 mobile video clips. We then compared the performance of the proposed methods with that of existing methods in terms of the differential mean opinion score with 120 mobile video clips. Experimental results showed that the proposed methods were approximately 10% better than the edge peak signal-to-noise ratio of the J.247 method in terms of the Pearson correlation.

Video Encryption and Decryption on Quantum Computers

NASA Astrophysics Data System (ADS)

Yan, Fei; Iliyasu, Abdullah M.; Venegas-Andraca, Salvador E.; Yang, Huamin

2015-08-01

A method for video encryption and decryption on quantum computers is proposed based on color information transformations on each frame encoding the content of the encoding the content of the video. The proposed method provides a flexible operation to encrypt quantum video by means of the quantum measurement in order to enhance the security of the video. To validate the proposed approach, a tetris tile-matching puzzle game video is utilized in the experimental simulations. The results obtained suggest that the proposed method enhances the security and speed of quantum video encryption and decryption, both properties required for secure transmission and sharing of video content in quantum communication.

Video Elicitation Interviews: A Qualitative Research Method for Investigating Physician-Patient Interactions

PubMed Central

Henry, Stephen G.; Fetters, Michael D.

2012-01-01

We describe the concept and method of video elicitation interviews and provide practical guidance for primary care researchers who want to use this qualitative method to investigate physician-patient interactions. During video elicitation interviews, researchers interview patients or physicians about a recent clinical interaction using a video recording of that interaction as an elicitation tool. Video elicitation is useful because it allows researchers to integrate data about the content of physician-patient interactions gained from video recordings with data about participants’ associated thoughts, beliefs, and emotions gained from elicitation interviews. This method also facilitates investigation of specific events or moments during interactions. Video elicitation interviews are logistically demanding and time consuming, and they should be reserved for research questions that cannot be fully addressed using either standard interviews or video recordings in isolation. As many components of primary care fall into this category, high-quality video elicitation interviews can be an important method for understanding and improving physician-patient interactions in primary care. PMID:22412003

Video elicitation interviews: a qualitative research method for investigating physician-patient interactions.

PubMed

Henry, Stephen G; Fetters, Michael D

2012-01-01

We describe the concept and method of video elicitation interviews and provide practical guidance for primary care researchers who want to use this qualitative method to investigate physician-patient interactions. During video elicitation interviews, researchers interview patients or physicians about a recent clinical interaction using a video recording of that interaction as an elicitation tool. Video elicitation is useful because it allows researchers to integrate data about the content of physician-patient interactions gained from video recordings with data about participants' associated thoughts, beliefs, and emotions gained from elicitation interviews. This method also facilitates investigation of specific events or moments during interactions. Video elicitation interviews are logistically demanding and time consuming, and they should be reserved for research questions that cannot be fully addressed using either standard interviews or video recordings in isolation. As many components of primary care fall into this category, high-quality video elicitation interviews can be an important method for understanding and improving physician-patient interactions in primary care.

Line Transect Surveys Underdetect Terrestrial Mammals: Implications for the Sustainability of Subsistence Hunting

PubMed Central

Levi, Taal; Oliveira, Luiz F. B.; Luzar, Jeffrey B.; Overman, Han; Read, Jane M.

2016-01-01

Conservation of Neotropical game species must take into account the livelihood and food security needs of local human populations. Hunting management decisions should therefore rely on abundance and distribution data that are as representative as possible of true population sizes and dynamics. We simultaneously applied a commonly used encounter-based method and an infrequently used sign-based method to estimate hunted vertebrate abundance in a 48,000-km2 indigenous landscape in southern Guyana. Diurnal direct encounter data collected during three years along 216, four-kilometer -long transects consistently under-detected many diurnal and nocturnal mammal species readily detected through sign. Of 32 species analyzed, 31 were detected by both methods; however, encounters did not detect one and under-detected another 12 of the most heavily hunted species relative to sign, while sign under-detected 12 never or rarely collected species relative to encounters. The six most important game animals in the region, all ungulates, were not encountered at 11–40% of village and control sites or on 29–72% of transects where they were detected by sign. Using the sign methodology, we find that tapirs, one of the terrestrial vertebrates considered most sensitive to overexploitation, are present at many sites where they were never visually detected during distance sampling. We find that this is true for many other species as well. These high rates of under-detection suggest that behavioral changes in hunted populations may affect apparent occurrence and abundance of these populations. Accumulation curves (detection of species on transects) were much steeper for sign for 12 of 16 hunted species than for encounters, but that pattern was reversed for 12 of 16 species unhunted in our area. We conclude that collection of sign data is an efficient and effective method of monitoring hunted vertebrate populations that complements encounter and camera-trapping methods in areas impacted by hunting. Sign surveys may be the most viable method for large-scale, management-oriented studies in remote areas, particularly those focused on community-based wildlife management. PMID:27074025

Clamp-Crushing versus stapler hepatectomy for transection of the parenchyma in elective hepatic resection (CRUNSH) - A randomized controlled trial (NCT01049607)

PubMed Central

2011-01-01

Background Hepatic resection is still associated with significant morbidity. Although the period of parenchymal transection presents a crucial step during the operation, uncertainty persists regarding the optimal technique of transection. It was the aim of the present randomized controlled trial to evaluate the efficacy and safety of hepatic resection using the technique of stapler hepatectomy compared to the simple clamp-crushing technique. Methods/Design The CRUNSH Trial is a prospective randomized controlled single-center trial with a two-group parallel design. Patients scheduled for elective hepatic resection without extrahepatic resection at the Department of General-, Visceral- and Transplantation Surgery, University of Heidelberg are enrolled into the trial and randomized intraoperatively to hepatic resection by the clamp-crushing technique and stapler hepatectomy, respectively. The primary endpoint is total intraoperative blood loss. A set of general and surgical variables are documented as secondary endpoints. Patients and outcome-assessors are blinded for the treatment intervention. Discussion The CRUNSH Trial is the first randomized controlled trial to evaluate efficacy and safety of stapler hepatectomy compared to the clamp-crushing technique for parenchymal transection during elective hepatic resection. Trial Registration ClinicalTrials.gov: NCT01049607 PMID:21888669

Bird Radar Validation in the Field by Time-Referencing Line-Transect Surveys

PubMed Central

Dokter, Adriaan M.; Baptist, Martin J.; Ens, Bruno J.; Krijgsveld, Karen L.; van Loon, E. Emiel

2013-01-01

Track-while-scan bird radars are widely used in ornithological studies, but often the precise detection capabilities of these systems are unknown. Quantification of radar performance is essential to avoid observational biases, which requires practical methods for validating a radar’s detection capability in specific field settings. In this study a method to quantify the detection capability of a bird radar is presented, as well a demonstration of this method in a case study. By time-referencing line-transect surveys, visually identified birds were automatically linked to individual tracks using their transect crossing time. Detection probabilities were determined as the fraction of the total set of visual observations that could be linked to radar tracks. To avoid ambiguities in assigning radar tracks to visual observations, the observer’s accuracy in determining a bird’s transect crossing time was taken into account. The accuracy was determined by examining the effect of a time lag applied to the visual observations on the number of matches found with radar tracks. Effects of flight altitude, distance, surface substrate and species size on the detection probability by the radar were quantified in a marine intertidal study area. Detection probability varied strongly with all these factors, as well as species-specific flight behaviour. The effective detection range for single birds flying at low altitude for an X-band marine radar based system was estimated at ∼1.5 km. Within this range the fraction of individual flying birds that were detected by the radar was 0.50±0.06 with a detection bias towards higher flight altitudes, larger birds and high tide situations. Besides radar validation, which we consider essential when quantification of bird numbers is important, our method of linking radar tracks to ground-truthed field observations can facilitate species-specific studies using surveillance radars. The methodology may prove equally useful for optimising tracking algorithms. PMID:24066103

Bird radar validation in the field by time-referencing line-transect surveys.

PubMed

Dokter, Adriaan M; Baptist, Martin J; Ens, Bruno J; Krijgsveld, Karen L; van Loon, E Emiel

2013-01-01

Track-while-scan bird radars are widely used in ornithological studies, but often the precise detection capabilities of these systems are unknown. Quantification of radar performance is essential to avoid observational biases, which requires practical methods for validating a radar's detection capability in specific field settings. In this study a method to quantify the detection capability of a bird radar is presented, as well a demonstration of this method in a case study. By time-referencing line-transect surveys, visually identified birds were automatically linked to individual tracks using their transect crossing time. Detection probabilities were determined as the fraction of the total set of visual observations that could be linked to radar tracks. To avoid ambiguities in assigning radar tracks to visual observations, the observer's accuracy in determining a bird's transect crossing time was taken into account. The accuracy was determined by examining the effect of a time lag applied to the visual observations on the number of matches found with radar tracks. Effects of flight altitude, distance, surface substrate and species size on the detection probability by the radar were quantified in a marine intertidal study area. Detection probability varied strongly with all these factors, as well as species-specific flight behaviour. The effective detection range for single birds flying at low altitude for an X-band marine radar based system was estimated at ~1.5 km. Within this range the fraction of individual flying birds that were detected by the radar was 0.50 ± 0.06 with a detection bias towards higher flight altitudes, larger birds and high tide situations. Besides radar validation, which we consider essential when quantification of bird numbers is important, our method of linking radar tracks to ground-truthed field observations can facilitate species-specific studies using surveillance radars. The methodology may prove equally useful for optimising tracking algorithms.

Saugus River and Tributaries, Lynn Malden, Revere and Saugus, Massachusetts. Flood Damage Reduction. Volume 8. Appendix K. Environmental

DTIC Science & Technology

1989-06-01

K10 Summary of Soil Analyses for the Salt Marsh Transects K32 KI1 Plant Community Composition Data Along Compartment K33 B Transect K12 Plant...Community Composition Data Along Compartment K33 I Transect K13 Plant Community Composition Data Along Compartment K33 K1 Transect K14 Plant Community... Composition Data Along Compartment K34 K3 Transect K15 Plant Community Composition Data Along Compartment K34 L2 Transect K16 Plant Community Composition

Video-Based Fingerprint Verification

PubMed Central

Qin, Wei; Yin, Yilong; Liu, Lili

2013-01-01

Conventional fingerprint verification systems use only static information. In this paper, fingerprint videos, which contain dynamic information, are utilized for verification. Fingerprint videos are acquired by the same capture device that acquires conventional fingerprint images, and the user experience of providing a fingerprint video is the same as that of providing a single impression. After preprocessing and aligning processes, “inside similarity” and “outside similarity” are defined and calculated to take advantage of both dynamic and static information contained in fingerprint videos. Match scores between two matching fingerprint videos are then calculated by combining the two kinds of similarity. Experimental results show that the proposed video-based method leads to a relative reduction of 60 percent in the equal error rate (EER) in comparison to the conventional single impression-based method. We also analyze the time complexity of our method when different combinations of strategies are used. Our method still outperforms the conventional method, even if both methods have the same time complexity. Finally, experimental results demonstrate that the proposed video-based method can lead to better accuracy than the multiple impressions fusion method, and the proposed method has a much lower false acceptance rate (FAR) when the false rejection rate (FRR) is quite low. PMID:24008283

The experiments and analysis of several selective video encryption methods

NASA Astrophysics Data System (ADS)

Zhang, Yue; Yang, Cheng; Wang, Lei

2013-07-01

This paper presents four methods for selective video encryption based on the MPEG-2 video compression,including the slices, the I-frames, the motion vectors, and the DCT coefficients. We use the AES encryption method for simulation experiment for the four methods on VS2010 Platform, and compare the video effects and the processing speed of each frame after the video encrypted. The encryption depth can be arbitrarily selected, and design the encryption depth by using the double limit counting method, so the accuracy can be increased.

Some comments on Anderson and Pospahala's correction of bias in line transect sampling

USGS Publications Warehouse

Anderson, D.R.; Burnham, K.P.; Chain, B.R.

1980-01-01

ANDERSON and POSPAHALA (1970) investigated the estimation of wildlife population size using the belt or line transect sampling method and devised a correction for bias, thus leading to an estimator with interesting characteristics. This work was given a uniform mathematical framework in BURNHAM and ANDERSON (1976). In this paper we show that the ANDERSON-POSPAHALA estimator is optimal in the sense of being the (unique) best linear unbiased estimator within the class of estimators which are linear combinations of cell frequencies, provided certain assumptions are met.

Top soil radioactivity assessment in a high natural radiation background area: the case of Vinaninkarena, Antsirabe-Madagascar.

PubMed

Rabesiranana, Naivo; Rasolonirina, Martin; Terina, Franck; Solonjara, Asivelo F; Andriambololona, Raoelina

2008-11-01

The village of Vinaninkarena, Antsirabe, Madagascar (47 degrees 02'40''E, 19 degrees 57'17''S) is located in a high natural radioactivity area. In order to evaluate the natural radionuclide content in soil, sampling was done on-site by the transect method (85 soil samples) and off-site through transects across and beyond the region (up to a range of 100 km), to determine the natural radioactivity variation within vs. outside the region, and to detect significant differences, taking into account spatial variability.

Topographic, bioclimatic, and vegetation characteristics of three ecoregion classification systems in North America: Comparisons along continent-wide transects

USGS Publications Warehouse

Thompson, R.S.; Shafer, S.L.; Anderson, K.H.; Strickland, L.E.; Pelltier, R.T.; Bartlein, P.J.; Kerwin, M.W.

2005-01-01

Ecoregion classification systems are increasingly used for policy and management decisions, particularly among conservation and natural resource managers. A number of ecoregion classification systems are currently available, with each system defining ecoregions using different classification methods and different types of data. As a result, each classification system describes a unique set of ecoregions. To help potential users choose the most appropriate ecoregion system for their particular application, we used three latitudinal transects across North America to compare the boundaries and environmental characteristics of three ecoregion classification systems [Ku??chler, World Wildlife Fund (WWF), and Bailey]. A variety of variables were used to evaluate the three systems, including woody plant species richness, normalized difference in vegetation index (NDVI), and bioclimatic variables (e.g., mean temperature of the coldest month) along each transect. Our results are dominated by geographic patterns in temperature, which are generally aligned north-south, and in moisture, which are generally aligned east-west. In the west, the dramatic changes in physiography, climate, and vegetation impose stronger controls on ecoregion boundaries than in the east. The Ku??chler system has the greatest number of ecoregions on all three transects, but does not necessarily have the highest degree of internal consistency within its ecoregions with regard to the bioclimatic and species richness data. In general, the WWF system appears to track climatic and floristic variables the best of the three systems, but not in all regions on all transects. ?? 2005 Springer Science+Business Media, Inc.

Web-video-mining-supported workflow modeling for laparoscopic surgeries.

PubMed

Liu, Rui; Zhang, Xiaoli; Zhang, Hao

2016-11-01

As quality assurance is of strong concern in advanced surgeries, intelligent surgical systems are expected to have knowledge such as the knowledge of the surgical workflow model (SWM) to support their intuitive cooperation with surgeons. For generating a robust and reliable SWM, a large amount of training data is required. However, training data collected by physically recording surgery operations is often limited and data collection is time-consuming and labor-intensive, severely influencing knowledge scalability of the surgical systems. The objective of this research is to solve the knowledge scalability problem in surgical workflow modeling with a low cost and labor efficient way. A novel web-video-mining-supported surgical workflow modeling (webSWM) method is developed. A novel video quality analysis method based on topic analysis and sentiment analysis techniques is developed to select high-quality videos from abundant and noisy web videos. A statistical learning method is then used to build the workflow model based on the selected videos. To test the effectiveness of the webSWM method, 250 web videos were mined to generate a surgical workflow for the robotic cholecystectomy surgery. The generated workflow was evaluated by 4 web-retrieved videos and 4 operation-room-recorded videos, respectively. The evaluation results (video selection consistency n-index ≥0.60; surgical workflow matching degree ≥0.84) proved the effectiveness of the webSWM method in generating robust and reliable SWM knowledge by mining web videos. With the webSWM method, abundant web videos were selected and a reliable SWM was modeled in a short time with low labor cost. Satisfied performances in mining web videos and learning surgery-related knowledge show that the webSWM method is promising in scaling knowledge for intelligent surgical systems. Copyright © 2016 Elsevier B.V. All rights reserved.

High-speed measurement of an air transect's temperature shift heated by laser beam

NASA Astrophysics Data System (ADS)

Li, WenYu; Jiang, ZongFu; Xi, Fengjie; Li, Qiang; Xie, Wenke

2005-02-01

Laser beam heat the air on the optic path, Beam-deflection optical tomography is a non-intrusive method to measure the 2-dimension temperature distribution in the transect. By means of linear Hartmann Sensor at the rate of 27kHz, the optic path was heated by a 2.7μm HF laser, continuous and high time resolution gradients of optic phase were obtained. the result of analysing and calculation showed the temperament shift in the heated beam path was not higher than 50K when the HF laser power was 9W. The experiment showed that it is a practical non-intrusive temperature shift measurement method for a small area aero-optical medium.

Estimation of low back moments from video analysis: a validation study.

PubMed

Coenen, Pieter; Kingma, Idsart; Boot, Cécile R L; Faber, Gert S; Xu, Xu; Bongers, Paulien M; van Dieën, Jaap H

2011-09-02

This study aimed to develop, compare and validate two versions of a video analysis method for assessment of low back moments during occupational lifting tasks since for epidemiological studies and ergonomic practice relatively cheap and easily applicable methods to assess low back loads are needed. Ten healthy subjects participated in a protocol comprising 12 lifting conditions. Low back moments were assessed using two variants of a video analysis method and a lab-based reference method. Repeated measures ANOVAs showed no overall differences in peak moments between the two versions of the video analysis method and the reference method. However, two conditions showed a minor overestimation of one of the video analysis method moments. Standard deviations were considerable suggesting that errors in the video analysis were random. Furthermore, there was a small underestimation of dynamic components and overestimation of the static components of the moments. Intraclass correlations coefficients for peak moments showed high correspondence (>0.85) of the video analyses with the reference method. It is concluded that, when a sufficient number of measurements can be taken, the video analysis method for assessment of low back loads during lifting tasks provides valid estimates of low back moments in ergonomic practice and epidemiological studies for lifts up to a moderate level of asymmetry. Copyright © 2011 Elsevier Ltd. All rights reserved.

Randomized clinical trial of stapler versus clamp-crushing transection in elective liver resection.

PubMed

Rahbari, N N; Elbers, H; Koch, M; Vogler, P; Striebel, F; Bruckner, T; Mehrabi, A; Schemmer, P; Büchler, M W; Weitz, J

2014-02-01

Various devices have been developed to facilitate liver transection and reduce blood loss in liver resections. None of these has proven superiority compared with the classical clamp-crushing technique. This randomized clinical trial compared the effectiveness and safety of stapler transection with that of clamp-crushing during open liver resection. Patients admitted for elective open liver resection between January 2010 and October 2011 were assigned randomly to stapler transection or the clamp-crushing technique. The primary endpoint was the total amount of intraoperative blood loss. Secondary endpoints included transection time, duration of operation, complication rates and resection margins. A total of 130 patients were enrolled, 65 to clamp-crushing and 65 to stapler transection. There was no difference between groups in total intraoperative blood loss: median (i.q.r.) 1050 (525-1650) versus 925 (450-1425) ml respectively (P = 0·279). The difference in total intraoperative blood loss normalized to the transection surface area was not statistically significant (P = 0·092). Blood loss during parenchymal transection was significantly lower in the stapler transection group (P = 0·002), as were the parenchymal transection time (mean(s.d.) 30(21) versus 9(7) min for clamp-crushing and stapler transection groups respectively; P < 0·001) and total duration of operation (mean(s.d.) 221(86) versus 190(85) min; P = 0·047). There were no significant differences in postoperative morbidity (P = 0·863) or mortality (P = 0·684) between groups. Stapler transection is a safe technique but does not reduce intraoperative blood loss in elective liver resection compared with the clamp-crushing technique. NCT01049607 (http://www.clinicaltrials.gov). © 2014 BJS Society Ltd. Published by John Wiley & Sons Ltd.

Dixie Valley, Nevada playa bathymetry constructed from Landsat TM data

NASA Astrophysics Data System (ADS)

Groeneveld, David P.; Barz, David D.

2014-05-01

A bathymetry model was developed from a series of Landsat Thematic Mapper (TM) images to assist discrimination of hydrologic processes on a low-relief, stable saline playa in Dixie Valley, Nevada, USA. The slope of the playa surface, established by field survey on a reference transect, enabled calculation of relative elevation of the edges of pooled brine mapped from Landsat TM5 band 5 reflectance (TMB5) in the 1.55-1.75 μm shortwave infrared region (SWIR) of the spectrum. A 0.02 TMB5 reflectance threshold accurately differentiated the shallow (1-2 mm depth) edges of pools. Isocontours of equal elevations of pool margins were mapped with the TMB5 threshold, forming concentric rings that were assigned relative elevations according to the position that the pool edges intersected the reference transect. These data were used to fit a digital elevation model and a curve for estimating pooled volume given the distance from the playa edge to the intersection of the pool edge with the reference transect. To project pooled volume using the bathymetric model for any TM snapshot, within a geographic information system, the 0.02 TMB5 threshold is first used to define the edge of the exposed brine. The distance of this edge from the playa edge along the reference transect is then measured and input to the bathymetric equation to yield pooled volume. Other satellite platforms with appropriate SWIR bands require calibration to Landsat TMB5. The method has applicability for filling reservoirs, bodies of water that fluctuate and especially bodies of water inaccessible to acoustic or sounding methods.

Double-observer line transect surveys with Markov-modulated Poisson process models for animal availability.

PubMed

Borchers, D L; Langrock, R

2015-12-01

We develop maximum likelihood methods for line transect surveys in which animals go undetected at distance zero, either because they are stochastically unavailable while within view or because they are missed when they are available. These incorporate a Markov-modulated Poisson process model for animal availability, allowing more clustered availability events than is possible with Poisson availability models. They include a mark-recapture component arising from the independent-observer survey, leading to more accurate estimation of detection probability given availability. We develop models for situations in which (a) multiple detections of the same individual are possible and (b) some or all of the availability process parameters are estimated from the line transect survey itself, rather than from independent data. We investigate estimator performance by simulation, and compare the multiple-detection estimators with estimators that use only initial detections of individuals, and with a single-observer estimator. Simultaneous estimation of detection function parameters and availability model parameters is shown to be feasible from the line transect survey alone with multiple detections and double-observer data but not with single-observer data. Recording multiple detections of individuals improves estimator precision substantially when estimating the availability model parameters from survey data, and we recommend that these data be gathered. We apply the methods to estimate detection probability from a double-observer survey of North Atlantic minke whales, and find that double-observer data greatly improve estimator precision here too. © 2015 The Authors Biometrics published by Wiley Periodicals, Inc. on behalf of International Biometric Society.

Log sampling methods and software for stand and landscape analyses.

Treesearch

Lisa J. Bate; Torolf R. Torgersen; Michael J. Wisdom; Edward O. Garton; Shawn C. Clabough

2008-01-01

We describe methods for efficient, accurate sampling of logs at landscape and stand scales to estimate density, total length, cover, volume, and weight. Our methods focus on optimizing the sampling effort by choosing an appropriate sampling method and transect length for specific forest conditions and objectives. Sampling methods include the line-intersect method and...

Defining biological assemblages (biotopes) of conservation interest in the submarine canyons of the South West Approaches (offshore United Kingdom) for use in marine habitat mapping

NASA Astrophysics Data System (ADS)

Davies, Jaime S.; Howell, Kerry L.; Stewart, Heather A.; Guinan, Janine; Golding, Neil

2014-06-01

In 2007, the upper part of a submarine canyon system located in water depths between 138 and 1165 m in the South West (SW) Approaches (North East Atlantic Ocean) was surveyed over a 2 week period. High-resolution multibeam echosounder data covering 1106 km2, and 44 ground-truthing video and image transects were acquired to characterise the biological assemblages of the canyons. The SW Approaches is an area of complex terrain, and intensive ground-truthing revealed the canyons to be dominated by soft sediment assemblages. A combination of multivariate analysis of seabed photographs (184-1059 m) and visual assessment of video ground-truthing identified 12 megabenthic assemblages (biotopes) at an appropriate scale to act as mapping units. Of these biotopes, 5 adhered to current definitions of habitats of conservation concern, 4 of which were classed as Vulnerable Marine Ecosystems. Some of the biotopes correspond to descriptions of communities from other megahabitat features (for example the continental shelf and seamounts), although it appears that the canyons host modified versions, possibly due to the inferred high rates of sedimentation in the canyons. Other biotopes described appear to be unique to canyon features, particularly the sea pen biotope consisting of Kophobelemnon stelliferum and cerianthids.

Do sampling methods differ in their utility for ecological monitoring? Comparison of line-point intercept, grid-point intercept, and ocular estimate methods

USDA-ARS?s Scientific Manuscript database

This study compared the utility of three sampling methods for ecological monitoring based on: interchangeability of data (rank correlations), precision (coefficient of variation), cost (minutes/transect), and potential of each method to generate multiple indicators. Species richness and foliar cover...

Video Vectorization via Tetrahedral Remeshing.

PubMed

Wang, Chuan; Zhu, Jie; Guo, Yanwen; Wang, Wenping

2017-02-09

We present a video vectorization method that generates a video in vector representation from an input video in raster representation. A vector-based video representation offers the benefits of vector graphics, such as compactness and scalability. The vector video we generate is represented by a simplified tetrahedral control mesh over the spatial-temporal video volume, with color attributes defined at the mesh vertices. We present novel techniques for simplification and subdivision of a tetrahedral mesh to achieve high simplification ratio while preserving features and ensuring color fidelity. From an input raster video, our method is capable of generating a compact video in vector representation that allows a faithful reconstruction with low reconstruction errors.

Procedural Documentation and Accuracy Assessment of Bathymetric Maps and Area/Capacity Tables for Small Reservoirs

USGS Publications Warehouse

Wilson, Gary L.; Richards, Joseph M.

2006-01-01

Because of the increasing use and importance of lakes for water supply to communities, a repeatable and reliable procedure to determine lake bathymetry and capacity is needed. A method to determine the accuracy of the procedure will help ensure proper collection and use of the data and resulting products. It is important to clearly define the intended products and desired accuracy before conducting the bathymetric survey to ensure proper data collection. A survey-grade echo sounder and differential global positioning system receivers were used to collect water-depth and position data in December 2003 at Sugar Creek Lake near Moberly, Missouri. Data were collected along planned transects, with an additional set of quality-assurance data collected for use in accuracy computations. All collected data were imported into a geographic information system database. A bathymetric surface model, contour map, and area/capacity tables were created from the geographic information system database. An accuracy assessment was completed on the collected data, bathymetric surface model, area/capacity table, and contour map products. Using established vertical accuracy standards, the accuracy of the collected data, bathymetric surface model, and contour map product was 0.67 foot, 0.91 foot, and 1.51 feet at the 95 percent confidence level. By comparing results from different transect intervals with the quality-assurance transect data, it was determined that a transect interval of 1 percent of the longitudinal length of Sugar Creek Lake produced nearly as good results as 0.5 percent transect interval for the bathymetric surface model, area/capacity table, and contour map products.

Towards a Video Passive Content Fingerprinting Method for Partial-Copy Detection Robust against Non-Simulated Attacks

PubMed Central

2016-01-01

Passive content fingerprinting is widely used for video content identification and monitoring. However, many challenges remain unsolved especially for partial-copies detection. The main challenge is to find the right balance between the computational cost of fingerprint extraction and fingerprint dimension, without compromising detection performance against various attacks (robustness). Fast video detection performance is desirable in several modern applications, for instance, in those where video detection involves the use of large video databases or in applications requiring real-time video detection of partial copies, a process whose difficulty increases when videos suffer severe transformations. In this context, conventional fingerprinting methods are not fully suitable to cope with the attacks and transformations mentioned before, either because the robustness of these methods is not enough or because their execution time is very high, where the time bottleneck is commonly found in the fingerprint extraction and matching operations. Motivated by these issues, in this work we propose a content fingerprinting method based on the extraction of a set of independent binary global and local fingerprints. Although these features are robust against common video transformations, their combination is more discriminant against severe video transformations such as signal processing attacks, geometric transformations and temporal and spatial desynchronization. Additionally, we use an efficient multilevel filtering system accelerating the processes of fingerprint extraction and matching. This multilevel filtering system helps to rapidly identify potential similar video copies upon which the fingerprint process is carried out only, thus saving computational time. We tested with datasets of real copied videos, and the results show how our method outperforms state-of-the-art methods regarding detection scores. Furthermore, the granularity of our method makes it suitable for partial-copy detection; that is, by processing only short segments of 1 second length. PMID:27861492

Line intersect sampling: Ell-shaped transects and multiple intersections

Treesearch

Timothy G. Gregoire; Harry T. Valentine

2003-01-01

The probability of selecting a population element under line intersect sampling depends on the width of the particle in the direction perpendicular to the transect, as is well known. The consequence of this when using ell-shaped transects rather than straight-line transects are explicated, and modifications that preserve design-unbiasedness of Kaiser's (1983)...

The response of tundra springtails (Collembola, Hexapoda) to human activity on the Murman coast of the Kola Penisula, Russia

NASA Astrophysics Data System (ADS)

Olejniczak, Izabella; Boniecki, Paweł; Kaliszewicz, Anita; Panteleeva, Ninel

2018-03-01

This study was carried out in the Dalne Zelentsy settlement (69°07‧N, 36°03‧E) on the Barents Sea of the Kola Penisula in Russia. Three transects were established: the 'new garden transect'; the 'old garden transect'; and the 'settlement transect'. Overall, the number of springtails increased with distance from the 'settlement' and decreased from the 'old garden' towards the tundra. However, in the case of the 'new garden transect' there were no clear trends in springtail abundance. Eleven species of springtail were found, with Parisotoma notabilis being found at each of the studied areas along the transects. Trends in the species diversity of the springtail communities were not clear, and the values of H‧ ranged from 1.36 to 2.08. The springtail communities located 10 m from the 'new garden' and the 'old garden' were characterized by low species diversity compared with the other sites along the transects (H‧ values of 1.36 and 1.67, respectively). There were no differences in species diversity among the springtail communities along the 'settlement transect'.

[Effects of grazing on zoobenthos community in beach].

PubMed

Zhao, Yun-long; An, Chuan-guang; Lin, Ling; Duan, Xiao-wei; Zeng, Cuo; Cui, Li-li

2007-05-01

In May (spring) and October (autumn) 2005, the effects of grazing on the zoobenthos community in Chongming Dongtan wetland of Shanghai were investigated. A total of 3 transects including 90 sampling plots were set up. Transects I and II were in feeding area, and transect III was in non-pasture area. All of these three transects were set in mid-tidal zone. 13 zoobenthos species were observed, with 7 species of arthropod, 4 species of mollusk, and 2 species of annelid. In spring, there were 6, 8 and 10 species in transects I , II and III while in autumn, the species number was 6, 8 and 12, respectively. The mean abundance of zoobenthos community in all transects was higher in autumn than in spring, and transect III had the highest mean abundance and biomass both in autumn and spring. Transect III also had the highest evenness, richness and diversity, indicating that grazing could change the species distribution of zoobenthos, and affect their abundance and biomass to different degree. Grazing had made certain negative effects on the biodiversity of zoobenthos community in Chongming Dongtan wetland.

Video Extrapolation Method Based on Time-Varying Energy Optimization and CIP.

PubMed

Sakaino, Hidetomo

2016-09-01

Video extrapolation/prediction methods are often used to synthesize new videos from images. For fluid-like images and dynamic textures as well as moving rigid objects, most state-of-the-art video extrapolation methods use non-physics-based models that learn orthogonal bases from a number of images but at high computation cost. Unfortunately, data truncation can cause image degradation, i.e., blur, artifact, and insufficient motion changes. To extrapolate videos that more strictly follow physical rules, this paper proposes a physics-based method that needs only a few images and is truncation-free. We utilize physics-based equations with image intensity and velocity: optical flow, Navier-Stokes, continuity, and advection equations. These allow us to use partial difference equations to deal with the local image feature changes. Image degradation during extrapolation is minimized by updating model parameters, where a novel time-varying energy balancer model that uses energy based image features, i.e., texture, velocity, and edge. Moreover, the advection equation is discretized by high-order constrained interpolation profile for lower quantization error than can be achieved by the previous finite difference method in long-term videos. Experiments show that the proposed energy based video extrapolation method outperforms the state-of-the-art video extrapolation methods in terms of image quality and computation cost.

Rotational stability test for the diagnosis of radial collateral ligament rupture in the fingers: Anatomical study.

PubMed

Lazarus, P; Hidalgo Diaz, J J; Prunières, G; Pire, E; Taleb, C; Honecker, S; Bellemère, P; Fontaine, C; Liverneaux, P A

2017-04-01

Diagnosing rupture of the radial collateral ligament (RCL) of the finger metacarpophalangeal (MCP) joints is difficult. The aim of this cadaver study was to validate a rotational test for the MCP after RCL transection. With the MCP and proximal interphalangeal joints in flexion, rotation along the axis of the proximal phalanx was applied through an extended distal interphalangeal joint to 36 cadaver fingers. Each finger's pulp described an arc of pronation and supination that was noted on the palm. The test was repeated three times: before transection, after transection of the proper collateral ligament (CL) and after transection of both the proper and accessory CLs. Rotational arcs were measured in pronation and supination. Mean length of the pronation arc after transection of the main RCL was 17.53mm, while it was only 12.41mm before transection for the supination arc. Mean length of the pronation arc after transection of both CLs was 22.83mm compared to only 11.93mm before transection. Our results show a significant difference in pronation stability of the MCP joint after transection of the RCL proper. We can conclude that this rotational stability test is a valid test for diagnosing RCL rupture in MCP joints. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

A novel sub-shot segmentation method for user-generated video

NASA Astrophysics Data System (ADS)

Lei, Zhuo; Zhang, Qian; Zheng, Chi; Qiu, Guoping

2018-04-01

With the proliferation of the user-generated videos, temporal segmentation is becoming a challengeable problem. Traditional video temporal segmentation methods like shot detection are not able to work on unedited user-generated videos, since they often only contain one single long shot. We propose a novel temporal segmentation framework for user-generated video. It finds similar frames with a tree partitioning min-Hash technique, constructs sparse temporal constrained affinity sub-graphs, and finally divides the video into sub-shot-level segments with a dense-neighbor-based clustering method. Experimental results show that our approach outperforms all the other related works. Furthermore, it is indicated that the proposed approach is able to segment user-generated videos at an average human level.

Data compression techniques applied to high resolution high frame rate video technology

NASA Technical Reports Server (NTRS)

Hartz, William G.; Alexovich, Robert E.; Neustadter, Marc S.

1989-01-01

An investigation is presented of video data compression applied to microgravity space experiments using High Resolution High Frame Rate Video Technology (HHVT). An extensive survey of methods of video data compression, described in the open literature, was conducted. The survey examines compression methods employing digital computing. The results of the survey are presented. They include a description of each method and assessment of image degradation and video data parameters. An assessment is made of present and near term future technology for implementation of video data compression in high speed imaging system. Results of the assessment are discussed and summarized. The results of a study of a baseline HHVT video system, and approaches for implementation of video data compression, are presented. Case studies of three microgravity experiments are presented and specific compression techniques and implementations are recommended.

Virtual viewpoint synthesis in multi-view video system

NASA Astrophysics Data System (ADS)

Li, Fang; Yang, Shiqiang

2005-07-01

In this paper, we present a virtual viewpoint video synthesis algorithm to satisfy the following three aims: low computing consuming; real time interpolation and acceptable video quality. In contrast with previous technologies, this method obtain incompletely 3D structure using neighbor video sources instead of getting total 3D information with all video sources, so that the computation is reduced greatly. So we demonstrate our interactive multi-view video synthesis algorithm in a personal computer. Furthermore, adopting the method of choosing feature points to build the correspondence between the frames captured by neighbor cameras, we need not require camera calibration. Finally, our method can be used when the angle between neighbor cameras is 25-30 degrees that it is much larger than common computer vision experiments. In this way, our method can be applied into many applications such as sports live, video conference, etc.

A novel Kalman filter based video image processing scheme for two-photon fluorescence microscopy

NASA Astrophysics Data System (ADS)

Sun, Wenqing; Huang, Xia; Li, Chunqiang; Xiao, Chuan; Qian, Wei

2016-03-01

Two-photon fluorescence microscopy (TPFM) is a perfect optical imaging equipment to monitor the interaction between fast moving viruses and hosts. However, due to strong unavoidable background noises from the culture, videos obtained by this technique are too noisy to elaborate this fast infection process without video image processing. In this study, we developed a novel scheme to eliminate background noises, recover background bacteria images and improve video qualities. In our scheme, we modified and implemented the following methods for both host and virus videos: correlation method, round identification method, tree-structured nonlinear filters, Kalman filters, and cell tracking method. After these procedures, most of noises were eliminated and host images were recovered with their moving directions and speed highlighted in the videos. From the analysis of the processed videos, 93% bacteria and 98% viruses were correctly detected in each frame on average.

Concerning the Video Drift Method to Measure Double Stars

NASA Astrophysics Data System (ADS)

Nugent, Richard L.; Iverson, Ernest W.

2015-05-01

Classical methods to measure position angles and separations of double stars rely on just a few measurements either from visual observations or photographic means. Visual and photographic CCD observations are subject to errors from the following sources: misalignments from eyepiece/camera/barlow lens/micrometer/focal reducers, systematic errors from uncorrected optical distortions, aberrations from the telescope system, camera tilt, magnitude and color effects. Conventional video methods rely on calibration doubles and graphically calculating the east-west direction plus careful choice of select video frames stacked for measurement. Atmospheric motion is one of the larger sources of error in any exposure/measurement method which is on the order of 0.5-1.5. Ideally, if a data set from a short video can be used to derive position angle and separation, with each data set self-calibrating independent of any calibration doubles or star catalogues, this would provide measurements of high systematic accuracy. These aims are achieved by the video drift method first proposed by the authors in 2011. This self calibrating video method automatically analyzes 1,000's of measurements from a short video clip.

Synchrotron X-ray microtransections: a non invasive approach for epileptic seizures arising from eloquent cortical areas

PubMed Central

Pouyatos, B.; Nemoz, C.; Chabrol, T.; Potez, M.; Bräuer, E.; Renaud, L.; Pernet-Gallay, K.; Estève, F.; David, O.; Kahane, P.; Laissue, J. A.; Depaulis, A.; Serduc, R.

2016-01-01

Synchrotron-generated X-ray (SRX) microbeams deposit high radiation doses to submillimetric targets whilst minimizing irradiation of neighboring healthy tissue. We developed a new radiosurgical method which demonstrably transects cortical brain tissue without affecting adjacent regions. We made such image-guided SRX microtransections in the left somatosensory cortex in a rat model of generalized epilepsy using high radiation doses (820 Gy) in thin (200 μm) parallel slices of tissue. This procedure, targeting the brain volume from which seizures arose, altered the abnormal neuronal activities for at least 9 weeks, as evidenced by a decrease of seizure power and coherence between tissue slices in comparison to the contralateral cortex. The brain tissue located between transections stayed histologically normal, while the irradiated micro-slices remained devoid of myelin and neurons two months after irradiation. This pre-clinical proof of concept highlights the translational potential of non-invasive SRX transections for treating epilepsies that are not eligible for resective surgery. PMID:27264273

Bilateral Traumatic Globe Luxation with Optic Nerve Transection

PubMed Central

Tok, Levent; Tok, Ozlem Yalcin; Argun, Tugba Cakmak; Yilmaz, Omer; Gunes, Alime; Unlu, Elif Nisa; Sezer, Sezgin; Ibisoglu, Seda; Argun, Mehmet

2014-01-01

Purpose The purpose of this study was to document clinical findings and management of a patient with bilateral globe luxation and optic nerve transection. Materials and Methods A 25-year-old female patient was admitted to the emergency department with bilateral traumatic globe luxation following a motor vehicle accident. Results Visual acuity testing showed no light perception. The right pupil was dilated and bilaterally did not react to light. The globes were bilaterally intact. A computed tomography scan revealed Le Fort type II fractures, bilateral optic nerve transection and disruption of all extraocular muscles. The globes of the patient were bilaterally reduced into the orbit. However, the patient developed phthisis bulbi in the right eye at month 3. Conclusion Globe luxation presents a dramatic clinical picture, and may lead to the development of severe complications due to the concomitance of complete optic nerve dissection and multiple traumas. Even if the luxated globe is repositioned into the orbit, there is still an increased risk of the development of phthisis due to ischemia. PMID:25606034

Importance of designated thoracic trauma surgeons in the management of traumatic aortic transection.

PubMed

Albrink, M H; Rodriguez, E; England, G J; McKeown, P P; Hurst, J M; Rosemurgy, A S

1994-04-01

The medical literature is replete with reports on traumatic aortic transection. These reports have delineated many factors regarding the morbidity and high mortality of this ominous injury. Most reports are reviews of the collective experience of a single institution over a period of years. It is likely that many authors writing on the subject of traumatic aortic transection have no experience with operative repair of the lesion. There has been debate about the various techniques of primary repair versus graft insertion, as well as the question of whether cardiopulmonary bypass is superior to the "clamp and sew" methods. No studies have directly examined the skills of individual surgeons with respect to outcome. We present the results of a study from a university-affiliated level I trauma center in which the outcomes from various groups of surgeons were compared over a 5-year period. The information in this study strongly suggests that designated thoracic trauma surgeons who are promptly available and have dedicated interests in trauma patients achieve better results.

Synchrotron X-ray microtransections: a non invasive approach for epileptic seizures arising from eloquent cortical areas

NASA Astrophysics Data System (ADS)

Pouyatos, B.; Nemoz, C.; Chabrol, T.; Potez, M.; Bräuer, E.; Renaud, L.; Pernet-Gallay, K.; Estève, F.; David, O.; Kahane, P.; Laissue, J. A.; Depaulis, A.; Serduc, R.

2016-06-01

Synchrotron-generated X-ray (SRX) microbeams deposit high radiation doses to submillimetric targets whilst minimizing irradiation of neighboring healthy tissue. We developed a new radiosurgical method which demonstrably transects cortical brain tissue without affecting adjacent regions. We made such image-guided SRX microtransections in the left somatosensory cortex in a rat model of generalized epilepsy using high radiation doses (820 Gy) in thin (200 μm) parallel slices of tissue. This procedure, targeting the brain volume from which seizures arose, altered the abnormal neuronal activities for at least 9 weeks, as evidenced by a decrease of seizure power and coherence between tissue slices in comparison to the contralateral cortex. The brain tissue located between transections stayed histologically normal, while the irradiated micro-slices remained devoid of myelin and neurons two months after irradiation. This pre-clinical proof of concept highlights the translational potential of non-invasive SRX transections for treating epilepsies that are not eligible for resective surgery.

Field data sets for seagrass biophysical properties for the Eastern Banks, Moreton Bay, Australia, 2004-2014

NASA Astrophysics Data System (ADS)

Roelfsema, Chris M.; Kovacs, Eva M.; Phinn, Stuart R.

2015-08-01

This paper describes seagrass species and percentage cover point-based field data sets derived from georeferenced photo transects. Annually or biannually over a ten year period (2004-2014) data sets were collected using 30-50 transects, 500-800 m in length distributed across a 142 km2 shallow, clear water seagrass habitat, the Eastern Banks, Moreton Bay, Australia. Each of the eight data sets include seagrass property information derived from approximately 3000 georeferenced, downward looking photographs captured at 2-4 m intervals along the transects. Photographs were manually interpreted to estimate seagrass species composition and percentage cover (Coral Point Count excel; CPCe). Understanding seagrass biology, ecology and dynamics for scientific and management purposes requires point-based data on species composition and cover. This data set, and the methods used to derive it are a globally unique example for seagrass ecological applications. It provides the basis for multiple further studies at this site, regional to global comparative studies, and, for the design of similar monitoring programs elsewhere.

Automatic video shot boundary detection using k-means clustering and improved adaptive dual threshold comparison

NASA Astrophysics Data System (ADS)

Sa, Qila; Wang, Zhihui

2018-03-01

At present, content-based video retrieval (CBVR) is the most mainstream video retrieval method, using the video features of its own to perform automatic identification and retrieval. This method involves a key technology, i.e. shot segmentation. In this paper, the method of automatic video shot boundary detection with K-means clustering and improved adaptive dual threshold comparison is proposed. First, extract the visual features of every frame and divide them into two categories using K-means clustering algorithm, namely, one with significant change and one with no significant change. Then, as to the classification results, utilize the improved adaptive dual threshold comparison method to determine the abrupt as well as gradual shot boundaries.Finally, achieve automatic video shot boundary detection system.

Status of important prey fishes in the U.S. waters of Lake Ontario, 2013: Introduction and methods, alewife, rainbow smelt, sculpins, and round goby

USGS Publications Warehouse

Walsh, Maureen; Weidel, Brian C.; Connerton, Michael J.

2014-01-01

Lake Ontario has a mean depth of 86 m (282 ft) and a maximum depth of 244 m (801 ft) (Herdendorf 1982). The southern, New York portion of the lake has the deepest water (Figure 1). In New York waters, about 67% of the lake is <160 m (525 ft) deep and about 82% of the lake is <180 m (591 ft) deep. The U.S. Geological Survey (USGS) and New York State Department of Environmental Conservation (NYSDEC) have cooperatively assessed Lake Ontario prey fishes each year since 1978. Bottom trawl assessments were initially focused on Alewife Alosa pseudoharengus (April), Rainbow Smelt Osmerus mordax (June), and Slimy Sculpin Cottus cognatus (October). Seasonal survey timing corresponded to the peak catches in 1972 when collections were made every month May to October (Owens et al. 2003). Twelve transects were established at approximately 25-km intervals along the U.S. shoreline (Figure 2). Alewife assessment was conducted at all transects, Rainbow Smelt assessment at all transects except Fair Haven, and six transects representing eastern, southern, and western lake areas were sampled for Slimy Sculpin (Figure 2). Changes in the Lake Ontario ecosystem (species invasion, oligotrophication, native species rebound) require ongoing evaluation of current methods which sometimes necessitate redistribution of trawl effort, or changes in sampling designs and/or gear. For instance, the spring Alewife assessment is now used also to assess invasive Round Goby Neogobius melanostomus population dynamics. Likewise, the fall benthic fish assessment (formerly sculpin assessment) now also tracks dynamics of the rebounding native Deepwater Sculpin Myoxocephalus thompsonii population, the apparent declining population of Slimy Sculpin, and fall distribution of Round Goby.

Line Intercept (LI)

Treesearch

John F. Caratti

2006-01-01

The FIREMON Line Intercept (LI) method is used to assess changes in plant species cover for a macroplot. This method uses multiple line transects to sample within plot variation and quantify statistically valid changes in plant species cover and height over time. This method is suited for most forest and rangeland communities, but is especially useful for sampling...

An aerial survey method to estimate sea otter abundance

USGS Publications Warehouse

Bodkin, James L.; Udevitz, Mark S.; Garner, Gerald W.; Amstrup, Steven C.; Laake, Jeffrey L.; Manly, Bryan F.J.; McDonald, Lyman L.; Robertson, Donna G.

1999-01-01

Sea otters (Enhydra lutris) occur in shallow coastal habitats and can be highly visible on the sea surface. They generally rest in groups and their detection depends on factors that include sea conditions, viewing platform, observer technique and skill, distance, habitat and group size. While visible on the surface, they are difficult to see while diving and may dive in response to an approaching survey platform. We developed and tested an aerial survey method that uses intensive searches within portions of strip transects to adjust for availability and sightability biases. Correction factors are estimated independently for each survey and observer. In tests of our method using shore-based observers, we estimated detection probabilities of 0.52-0.72 in standard strip-transects and 0.96 in intensive searches. We used the survey method in Prince William Sound, Alaska to estimate a sea otter population size of 9,092 (SE = 1422). The new method represents an improvement over various aspects of previous methods, but additional development and testing will be required prior to its broad application.

Factors controlling floc settling velocity along a longitudinal estuarine transect

USGS Publications Warehouse

Manning, A.J.; Schoellhamer, D.H.

2013-01-01

A 147 km longitudinal transect of flocculated cohesive sediment properties in San Francisco Bay (SFB) was conducted on June 17th, 2008. Our aim was to determine the factors that control floc settling velocity along the longitudinal axis of the estuary. The INSSEV-LF video system was used to measure floc diameters and settling velocities at 30 stations at a distance of 0.7 m above the estuary bed. Floc sizes (D) ranged from 22 μm to 639 μm and settling velocities (Ws) ranged between 0.04 mm·s− 1 and 15.8 mm·s− 1 during the longitudinal transect. Nearbed turbulent shear stresses throughout the transect duration were within the 0.2–0.5 Pa range which typically stimulates flocculation growth. The individual D–Ws–floc density plots suggest the suspended sediments encountered throughout SFB were composed of both muddy cohesive sediment and mixed sediments flocs. Mass-weighted population mean settling velocity (Wsmass) ranged from 0.5 mm·s− 1 to 10 mm·s− 1. The macrofloc and microfloc (demarcation at 160 μm) sub-populations demonstrated parameterised settling velocities which spanned nearly double the range of the sample mean settling velocities (Wsmean). The macroflocs tended to dominate the suspended mass (up to 77% of the ambient suspended solid concentration; SSC) from San Pablo Bay to Carquinez Strait (the vicinity of the turbidity maximum zone). Microfloc mass was particularly significant (typically 60–100% of the SSC) in the northern section of South Bay and most of Central Bay. The transect took eleven hours to complete and was not fully synoptic. During slack tide, larger and faster settling flocs deposited, accounting for most of the longitudinal variability. The best single predictor of settling velocity was water velocity 39 min prior to sampling, not suspended-sediment concentration or salinity. Resuspension and settling lags are likely responsible for the lagged response of settling velocity to water velocity. The distribution of individual floc diameters and settling velocities indicates that floc density for a given floc diameter varies greatly. A small portion (a few percent) of suspended sediment mass in SFB is sand-sized and inclusion of sand in flocs appears likely. Fractal theory for cohesive sediment assumes that there is a single primary particle size that flocculates, which is not the case for these types of mixed sediment flocs. The wide variability in the physical, biological and chemical processes which contribute to flocculation within SFB means that spatial floc data is required in order to accurately represent the diverse floc dynamics present in the Bay system. The importance in determining accurate estimates of floc density has been highlighted by the SFB data, as these provide the basis for realistic distributions of floc dry mass and the mass settling flux across a floc population. However, although video floc sampling devices can produce the various floc property trends observed in SFB, good survey practice is still paramount. One can see that if the sampling coverage (i.e. data collection frequency) is poor, this could lead to potential mis-interpretations of the data and only limited conclusions may be drawn from such a restricted survey. For example, a limited survey (i.e. only 3 stations, compared to the 10 stations in the full survey) in South Bay produces an under-estimate in both the macrofloc SSCmacro distribution by a factor of four and the Wsmacro by a factor of two. To develop sediment transport numerical models for SFB, high quality floc size and settling data are needed to understand and simulate the depositional qualities of both suspended cohesive sediment and mixed sediments in San Francisco Bay. This study has shown that the most pragmatic solution is a physically-based approach, whereby the detailed flocs D vs. Ws spectra are parameterised in terms of their macrofloc and microfloc properties. This aids in model calibration, whilst retaining more of the dynamical aspects of the floc populations. All forms of flocculation are dynamically active processes, therefore it is important to also include both SSC and turbulence functions together with the floc data.

The Relationship Between Method of Viewing Lectures, Course Ratings, and Course Timing

PubMed Central

Burton, William B; Ma, Terence P; Grayson, Martha S

2017-01-01

Background: In recent years, medical schools have provided students access to video recordings of course lectures, but few studies have investigated the impact of this on ratings of courses and teachers. This study investigated whether the method of viewing lectures was related to student ratings of the course and its components and whether the method used changed over time. Methods: Preclinical medical students indicated whether ratings of course lectures were based primarily on lecture attendance, video capture, or both. Students were categorized into Lecture, Video, or Both groups based on their responses to this question. The data consisted of 7584 student evaluations collected over 2 years. Results: Students who attended live lectures rated the course and its components higher than students who only viewed the video or used both methods, although these differences were very small. Students increasingly watched lectures exclusively by video over time: in comparison with first-year students, second-year students were more likely to watch lectures exclusively by video; in comparison with students in the first half of the academic year, students in the second half of the academic year were more likely to watch lectures exclusively by video. Conclusions: With the increase in use of lecture video recordings across medical schools, attention must be paid to student attitudes regarding these methods. PMID:29349337

Barrier effects of remote high mountain on atmospheric metal transport in the eastern Tibetan Plateau.

PubMed

Bing, Haijian; Zhou, Jun; Wu, Yanhong; Luo, Xiaosan; Xiang, Zhongxiang; Sun, Hongyang; Wang, Jipeng; Zhu, He

2018-07-01

Anthropogenic metals adsorbed on suspended fine particles can be deposited on remote and inaccessible high mountains by long-range atmospheric transport. In this study, we investigated the cadmium (Cd) and lead (Pb) in the soils, mosses and rainfall of three transects on the Gongga Mountain, eastern Tibetan Plateau, to understand the mountain interception effects on their atmospheric transport. The concentrations of Cd and Pb in the soils and mosses displayed a pattern of eastern transect>northern transect>western transect. The distribution of Cd and Pb on the eastern transect increased from 2000 to 2900m a.s.l. (above sea level), decreased toward the timberline, and increased again with altitude; on the northern transect, it generally decreased with altitude whereas a distribution trend was not clearly observed on the western transect. The Cd and Pb concentrations in the rainfall of the eastern transect generally decreased with altitude, and they were higher inside forests than outside forests and temporally higher in the winter than the summer. The Pb isotopic ratios coupled with moss bio-monitoring distinguished anthropogenic sources of Cd and Pb on the eastern and northern transects, whereas bedrock weathering was the main source of Cd and Pb on the western transect. We proposed a conceptual model to delineate the effects of terrain, local climate and vegetation on the transport of atmospheric metals. Our results highlighted the high mountains in the eastern Tibetan Plateau as an effective natural barrier limiting atmospheric metal transport. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparison of Two Multifractal Analysis Methods: Generalized Structure Function and Multifractal Spectrum

NASA Astrophysics Data System (ADS)

Morato, M. Carmen; Castellanos, M. Teresa; Bird, Nigel; Tarquis, Ana M.

2016-04-01

Soil variability has often been a constant expected factor to take in account in soil studies. This variability could be considered to be composed of "functional" variations plus random fluctuations or noise. Multifractal formalism, first proposed by Mandelbrot (1982), is suitable for variables with self-similar distribution on a spatial domain. Multifractal analysis can provide insight into spatial variability of crop or soil parameters. In soil science, it has been quite popular to characterize the scaling property of a variable measured along a transect as a mass distribution of a statistical measure on a length domain of the studied transect. To do this, it divides it into a number of self similar segments and estimate the partition function and mass function. Based on this, the multifractal spectra (MFS) is calculated. However, another technique can be applied focus its attention in the variations of a measure analyzing the moments of the absolute differences at different scales, the Generalized Structure Function (GSF), and extracting the Generalized Hurst exponents. The aim of this study is to compare both techniques in a transect data. A common 1024 m transect across arable fields at Silsoe in Bedfordshire, east-central England were analyzed with these two multifractal methods. Properties studied were total porosity (Porosity), gravimetric water content (GWC) and nitrogen oxide flux (NO2 flux). The results showed in both methods that NO2 flux presents a clear multifractal character and a weak one in the GWC and Porosity cases. Several parameters were calculated from both methods and are discussed. On the other hand, using the partition function all the scale ranges were used, meanwhile in the GSF a shorter range of scales showed linear behavior in the bilog plots used to estimate the parameters. GWC exhibits a linear pattern from increments of 4 till 256 meters, Porosity showed this behavior from 4 till 64 meters. In case of NO2 flux only from 32 to 256 meters showed it. However, the relation between the mass exponent function and the GSF, found in the literature, was positively verified in the three variables.

Comparison of line transects and point counts for monitoring spring migration in forested wetlands

USGS Publications Warehouse

Wilson, R.R.; Twedt, D.J.; Elliott, A.B.

2000-01-01

We compared the efficacy of 400-m line transects and sets of three point counts at detecting avian richness and abundance in bottomland hardwood forests and intensively managed cottonwood (Populus deltoides) plantations within the Mississippi Alluvial Valley. We detected more species and more individuals on line transects than on three point counts during 218 paired surveys conducted between 24 March and 3 June, 1996 and 1997. Line transects also yielded more birds per unit of time, even though point counts yielded higher estimates of relative bird density. In structurally more-complex bottomland hardwood forests, we detected more species and individuals on line transects, but in more-open cottonwood plantations, transects surpassed point counts only at detecting species within 50 m of the observer. Species richness and total abundance of Nearctic-Neotropical migrants and temperate migrants were greater on line transects within bottomland hardwood forests. Within cottonwood plantations, however, only species richness of Nearctic-Neotropical migrants and total abundance of temperate migrants were greater on line transects. Because we compared survey techniques using the same observer, within the same forest stand on a given day, we assumed that the technique yielding greater estimates of avian species richness and total abundance per unit of effort is superior. Thus, for monitoring migration within hardwood forests of the Mississippi Alluvial Valley, we recommend using line transects instead of point counts.

Video error concealment using block matching and frequency selective extrapolation algorithms

NASA Astrophysics Data System (ADS)

P. K., Rajani; Khaparde, Arti

2017-06-01

Error Concealment (EC) is a technique at the decoder side to hide the transmission errors. It is done by analyzing the spatial or temporal information from available video frames. It is very important to recover distorted video because they are used for various applications such as video-telephone, video-conference, TV, DVD, internet video streaming, video games etc .Retransmission-based and resilient-based methods, are also used for error removal. But these methods add delay and redundant data. So error concealment is the best option for error hiding. In this paper, the error concealment methods such as Block Matching error concealment algorithm is compared with Frequency Selective Extrapolation algorithm. Both the works are based on concealment of manually error video frames as input. The parameter used for objective quality measurement was PSNR (Peak Signal to Noise Ratio) and SSIM(Structural Similarity Index). The original video frames along with error video frames are compared with both the Error concealment algorithms. According to simulation results, Frequency Selective Extrapolation is showing better quality measures such as 48% improved PSNR and 94% increased SSIM than Block Matching Algorithm.

Real-time CT-video registration for continuous endoscopic guidance

NASA Astrophysics Data System (ADS)

Merritt, Scott A.; Rai, Lav; Higgins, William E.

2006-03-01

Previous research has shown that CT-image-based guidance could be useful for the bronchoscopic assessment of lung cancer. This research drew upon the registration of bronchoscopic video images to CT-based endoluminal renderings of the airway tree. The proposed methods either were restricted to discrete single-frame registration, which took several seconds to complete, or required non-real-time buffering and processing of video sequences. We have devised a fast 2D/3D image registration method that performs single-frame CT-Video registration in under 1/15th of a second. This allows the method to be used for real-time registration at full video frame rates without significantly altering the physician's behavior. The method achieves its speed through a gradient-based optimization method that allows most of the computation to be performed off-line. During live registration, the optimization iteratively steps toward the locally optimal viewpoint at which a CT-based endoluminal view is most similar to a current bronchoscopic video frame. After an initial registration to begin the process (generally done in the trachea for bronchoscopy), subsequent registrations are performed in real-time on each incoming video frame. As each new bronchoscopic video frame becomes available, the current optimization is initialized using the previous frame's optimization result, allowing continuous guidance to proceed without manual re-initialization. Tests were performed using both synthetic and pre-recorded bronchoscopic video. The results show that the method is robust to initialization errors, that registration accuracy is high, and that continuous registration can proceed on real-time video at >15 frames per sec. with minimal user-intervention.

Comparison between surgical and standing percutaneous contact Nd:YAG laser periosteal transection for potential treatment of equine limb deformities

NASA Astrophysics Data System (ADS)

Tate, Lloyd P.; Baines, Steven J.; Meuten, Donald J.; Stefanacci, J.

1994-09-01

Medial and lateral aspects of both radiuses were subjected to periosteal transection of nine healthy equine foals. One site per foal was subjected to surgical periosteal transection and elevation under general anesthesia. The remaining three sites of each foal after injection of a local anesthetic received Nd:YAG contact percutaneous periosteal transection. All radiuses were evaluated radiographically prior to periosteal transection and immediately prior to euthanasia. Foals were euthanized at 3 days, 31 to 34 days, and 67 days post-periosteal transection and gross postmortem and histologic examination performed on each site. Radiographically, periosteal proliferation occurred at all the conventional surgery sites and a majority of the percutaneous laser sites by 30 days post-treatment and was present at 67 days. No limb angulations were noted to occur in any of the foals. The conclusion of the study was that Nd:YAG percutaneous laser periosteal transection was successful in producing periosteal obliteration but with a different histologic appearance than that produced by conventional surgery.

Non-transecting bulbar urethroplasty

PubMed Central

Andrich, Daniela E.; Mundy, Anthony R.

2015-01-01

Excision and end-to-end anastomosis (EPA) has been the preferred urethroplasty technique for short bulbar strictures and is associated with an excellent functional outcome. Driven by concerns over the potential morbidity associated with dividing the urethra, therefore compromising spongiosal blood flow, as well as spongiofibrosis being superficial in the majority of non-traumatic bulbar strictures, the non-transecting technique for bulbar urethroplasty has been developed with the aim of achieving the same success as EPA without the morbidity associated with transection. This manuscript highlights the fundamental principles underlying the ongoing debate—transection or non-transection of the strictured bulbar urethra? The potential advantages of avoiding dividing the corpus spongiosum of the urethra are discussed. The non-transecting anastomotic procedure together with its various modifications are decribed in detail. Our experience with this technique is presented. Non-transecting excision of spongiofibrosis with preservation of well vascularised underlying spongiosum provides an excellent alternative to dividing the urethra during urethroplasty for short non-traumatic proximal bulbar strictures. PMID:26816808

Detection of Upscale-Crop and Partial Manipulation in Surveillance Video Based on Sensor Pattern Noise

PubMed Central

Hyun, Dai-Kyung; Ryu, Seung-Jin; Lee, Hae-Yeoun; Lee, Heung-Kyu

2013-01-01

In many court cases, surveillance videos are used as significant court evidence. As these surveillance videos can easily be forged, it may cause serious social issues, such as convicting an innocent person. Nevertheless, there is little research being done on forgery of surveillance videos. This paper proposes a forensic technique to detect forgeries of surveillance video based on sensor pattern noise (SPN). We exploit the scaling invariance of the minimum average correlation energy Mellin radial harmonic (MACE-MRH) correlation filter to reliably unveil traces of upscaling in videos. By excluding the high-frequency components of the investigated video and adaptively choosing the size of the local search window, the proposed method effectively localizes partially manipulated regions. Empirical evidence from a large database of test videos, including RGB (Red, Green, Blue)/infrared video, dynamic-/static-scene video and compressed video, indicates the superior performance of the proposed method. PMID:24051524

Perceptual video quality assessment in H.264 video coding standard using objective modeling.

PubMed

Karthikeyan, Ramasamy; Sainarayanan, Gopalakrishnan; Deepa, Subramaniam Nachimuthu

2014-01-01

Since usage of digital video is wide spread nowadays, quality considerations have become essential, and industry demand for video quality measurement is rising. This proposal provides a method of perceptual quality assessment in H.264 standard encoder using objective modeling. For this purpose, quality impairments are calculated and a model is developed to compute the perceptual video quality metric based on no reference method. Because of the shuttle difference between the original video and the encoded video the quality of the encoded picture gets degraded, this quality difference is introduced by the encoding process like Intra and Inter prediction. The proposed model takes into account of the artifacts introduced by these spatial and temporal activities in the hybrid block based coding methods and an objective modeling of these artifacts into subjective quality estimation is proposed. The proposed model calculates the objective quality metric using subjective impairments; blockiness, blur and jerkiness compared to the existing bitrate only calculation defined in the ITU G 1070 model. The accuracy of the proposed perceptual video quality metrics is compared against popular full reference objective methods as defined by VQEG.

Multibeam Mapping and Remotely Operated Vehicle Exploration of the Puerto Rico and Virgin Islands Region

NASA Astrophysics Data System (ADS)

Coleman, D. F.; Ten Brink, U. S.; Armstrong, R.; Chaytor, J. D.; Demopoulos, A. W.

2013-12-01

During October 2013, an ocean exploration project took place off the coast of Puerto Rico and the Virgin Islands. This project, a collaborative effort between the Ocean Exploration Trust, the US Geological Survey, the University of Puerto Rico at Mayaguez, the University of Rhode Island, and NOAA, was aimed at exploring regions of the US exclusive economic zone (EEZ) south of the Puerto Rico Trench axis, and north of Mona Island, Puerto Rico, and the US and British Virgin Islands, and portions of the Anegada Passage. The research vessel E/V Nautilus and the Hercules/Argus ROV system were used to expand the multibeam sonar bathymetric data coverage of the region, collect high definition video footage of seafloor features, and to collect biological and geological samples along selected transects. Particular areas of interest for targeted ROV dives included: the region where a large M7.2 1918 earthquake produced a tsunami that struck northwestern corner of Puerto Rico; a transect up the vertical wall of the Mona Rift (4000 to 1500 m depth); transects along the Septentrional fault system; dives in areas of suspected fluid flow through faults, fissures, and offshore Karst systems associated with the tilted carbonate platform north of Puerto Rico; dives in the Anegada Passage at the entry points for surface Atlantic waters that circulate into the Caribbean; and in regions to investigate and date sedimentary features offset by fault motion and potential tsunamigenic landslides. Biological sampling of many deep-sea benthic organisms (including deep water corals) have never been attempted before in this area. These samples are being used to understand more about the diversity, population dynamics, genetics, and habitat connectivity of these communities, and to provide an age constraint for disturbed sedimentary features. Until this cruise, the location and distribution of deep coral habitats in the US Caribbean was largely unknown. The available information on benthic communities associated with deep coral ecosystems in this region was mostly limited to taxonomic listings from incidental collections by fish traps, shrimp trawls and coral entanglement devices. We present the results of the first direct observations and sampling of these ecosystems.

A nearshore processes field experiment at Cape Hatteras, North Carolina, U.S.A.

USGS Publications Warehouse

List, Jeffrey H.; Warner, John C.; Thieler, E. Robert; Haas, Kevin; Voulgaris, George; McNinch, Jesse E.; Brodie, Katherine L.; Rosati, Julie D.; Wang, Ping; Roberts, Tiffany M.

2011-01-01

A month-long field experiment focused on the nearshore hydrodynamics of Diamond Shoals adjacent to Cape Hatteras Point, North Carolina, was conducted in February 2010. The objectives of this multi-institutional experiment were to test hypotheses related to Diamond Shoals as a sink in the regional sediment budget and to provide data for evaluating numerical models. The experiment included in-situ instrumentation for measuring waves and currents; a video camera system for measuring surface currents at a nearshore transect; a radar system for measuring regional surface currents over Diamond Shoals and the adjacent coast; a vehicle-based scanning lidar and radar system for mapping beach topography, nearshore wave breaking intensity, bathymetry (through wave celerity inversion), and wave direction; and an amphibious vehicle system for surveying single-beam bathymetry. Preliminary results from wave and current measurements suggest that shoal-building processes were active during the experiment.

Large-Vessel Sealing in Laparoscopic Colectomy with an Ultrasonic Device

PubMed Central

Plasencia, Gustavo; Van der Speeten, Kurt; Hinoul, Piet; Batiller, Jonathan; Severin, Kimberley S.; Schwiers, Michael L.; Rockall, Tim

2016-01-01

Background and Objective: The Harmonic ACE+7 Shears with Advanced Hemostasis Mode (Ethicon, Somerville, NJ, USA) is an ultrasonic device designed to transect and seal vessels up to 7 mm in diameter. The device applies an algorithm that optimizes ultrasonic energy delivery combined with a longer sealing cycle. The purpose of this study was to assess the initial clinical experience with the Harmonic device by evaluating large-vessel sealing during laparoscopic colectomy in consecutive cases. Methods: This prospective, multicenter, observational series involved 40 adult patients who were to undergo elective laparoscopic colectomy where dissection and transection of the inferior mesenteric artery was indicated. The primary study endpoint was first-pass hemostasis, defined as a single activation of the Advanced Hemostasis Mode to transect and seal the inferior mesenteric artery. The use of any additional energy device or hemostatic product to establish or maintain hemostasis was noted. Patients were observed after surgery for ∼4 weeks for adverse events that were considered to be related to the study procedure or study device. Descriptive statistical analyses were performed for study endpoints. Results: Forty patients underwent the laparoscopic colectomy procedure. First-pass hemostasis of the inferior mesenteric artery was achieved and maintained in all 40 patients, with no required additional hemostatic measures. Exposure of the vessel was reported as skeletonized in 22 of 40 (55%) patients. Mean transection time was 21.9 ± 7.4 s. One adverse event (postoperative anemia) was considered possibly related to the study device. Conclusion: In this initial clinical consecutive series, the device demonstrated successful transection and sealing of the large mesenteric vessels during laparoscopic colorectal surgery. PMID:27186065

Major- and trace-element concentrations in soils from two continental-scale transects of the United States and Canada

USGS Publications Warehouse

Smith, David B.; Cannon, William F.; Woodruff, Laurel G.; Garrett, Robert G.; Klassen, Rodney; Kilburn, James E.; Horton, John D.; King, Harley D.; Goldhaber, Martin B.; Morrison, Jean M.

2005-01-01

This report contains major- and trace-element concentration data for soil samples collected from 265 sites along two continental-scale transects in North America. One of the transects extends from northern Manitoba to the United States-Mexico border near El Paso, Tex. and consists of 105 sites. The other transect approximately follows the 38th parallel from the Pacific coast of the United States near San Francisco, Calif., to the Atlantic coast along the Maryland shore and consists of 160 sites. Sampling sites were defined by first dividing each transect into approximately 40-km segments. For each segment, a 1-km-wide latitudinal strip was randomly selected; within each strip, a potential sample site was selected from the most representative landscape within the most common soil type. At one in four sites, duplicate samples were collected 10 meters apart to estimate local spatial variability. At each site, up to four separate soil samples were collected as follows: (1) material from 0-5 cm depth; (2) O horizon, if present; (3) a composite of the A horizon; and (4) C horizon. Each sample collected was analyzed for total major- and trace-element composition by the following methods: (1) inductively coupled plasmamass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICPAES) for aluminum, antimony, arsenic, barium, beryllium, bismuth, cadmium, calcium, cerium, cesium, chromium, cobalt, copper, gallium, indium, iron, lanthanum, lead, lithium, magnesium, manganese, molybdenum, nickel, niobium, phosphorus, potassium, rubidium, scandium, silver, sodium, strontium, sulfur, tellurium, thallium, thorium, tin, titanium, tungsten, uranium, vanadium, yttrium, and zinc; (2) cold vapor- atomic absorption spectrometry for mercury; (3) hydride generation-atomic absorption spectrometry for antimony and selenium; (4) coulometric titration for carbonate carbon; and (5) combustion for total carbon and total sulfur.

Examining patterns of bat activity in Bandelier National Monument, New Mexico, using walking point transects

USGS Publications Warehouse

Ellison, L.E.; Everette, A.L.; Bogan, M.A.

2005-01-01

We conducted a preliminary study using small field crews, a single Anabat II detector coupled with a laptop computer, and point transects to examine patterns of bat activity at a scale of interest to local resource managers. The study was conducted during summers of 1996–1998 in Bandelier National Monument in the Jemez Mountains of northern New Mexico, a landscape with distinct vegetation zones and high species richness of bats. We developed simple models that described general patterns of acoustic activity within 4 vegetation zones based primarily on nightly variation and a qualitative index of habitat complexity. Bat acoustic activity (number of bat passes&sol point) did not vary dramatically among a limited sample of transects within a vegetation zone during 1996. In 1997 and 1998, single transects within each vegetation zone were established, and bat activity did not vary annually within these zones. Acoustic activity differed among the 4 vegetation zones of interest, with the greatest activity occurring in riparian canyon bottomland, intermediate activity in coniferous forest and a 1977 burned zone, and lowest activity in piñon-juniper woodlands. We identified 68.5% of 2,529 bat passes recorded during point-transect surveys to species using an echolocation call reference library we established for the area and qualitative characteristics of bat calls. Bat species richness and composition differed among vegetation zones. Results of these efforts were consistent with general knowledge of where different bat species typically forage and with the natural history of bats of New Mexico, suggesting such a method might have value for drawing inferences about bat activity in different vegetation zones.

Video quality assessment using motion-compensated temporal filtering and manifold feature similarity

PubMed Central

Yu, Mei; Jiang, Gangyi; Shao, Feng; Peng, Zongju

2017-01-01

Well-performed Video quality assessment (VQA) method should be consistent with human visual systems for better prediction accuracy. In this paper, we propose a VQA method using motion-compensated temporal filtering (MCTF) and manifold feature similarity. To be more specific, a group of frames (GoF) is first decomposed into a temporal high-pass component (HPC) and a temporal low-pass component (LPC) by MCTF. Following this, manifold feature learning (MFL) and phase congruency (PC) are used to predict the quality of temporal LPC and temporal HPC respectively. The quality measures of the LPC and the HPC are then combined as GoF quality. A temporal pooling strategy is subsequently used to integrate GoF qualities into an overall video quality. The proposed VQA method appropriately processes temporal information in video by MCTF and temporal pooling strategy, and simulate human visual perception by MFL. Experiments on publicly available video quality database showed that in comparison with several state-of-the-art VQA methods, the proposed VQA method achieves better consistency with subjective video quality and can predict video quality more accurately. PMID:28445489

Incentives Increase Participation in Mass Dog Rabies Vaccination Clinics and Methods of Coverage Estimation Are Assessed to Be Accurate

PubMed Central

Steinmetz, Melissa; Czupryna, Anna; Bigambo, Machunde; Mzimbiri, Imam; Powell, George; Gwakisa, Paul

2015-01-01

In this study we show that incentives (dog collars and owner wristbands) are effective at increasing owner participation in mass dog rabies vaccination clinics and we conclude that household questionnaire surveys and the mark-re-sight (transect survey) method for estimating post-vaccination coverage are accurate when all dogs, including puppies, are included. Incentives were distributed during central-point rabies vaccination clinics in northern Tanzania to quantify their effect on owner participation. In villages where incentives were handed out participation increased, with an average of 34 more dogs being vaccinated. Through economies of scale, this represents a reduction in the cost-per-dog of $0.47. This represents the price-threshold under which the cost of the incentive used must fall to be economically viable. Additionally, vaccination coverage levels were determined in ten villages through the gold-standard village-wide census technique, as well as through two cheaper and quicker methods (randomized household questionnaire and the transect survey). Cost data were also collected. Both non-gold standard methods were found to be accurate when puppies were included in the calculations, although the transect survey and the household questionnaire survey over- and under-estimated the coverage respectively. Given that additional demographic data can be collected through the household questionnaire survey, and that its estimate of coverage is more conservative, we recommend this method. Despite the use of incentives the average vaccination coverage was below the 70% threshold for eliminating rabies. We discuss the reasons and suggest solutions to improve coverage. Given recent international targets to eliminate rabies, this study provides valuable and timely data to help improve mass dog vaccination programs in Africa and elsewhere. PMID:26633821

The influence of transection site on the development of pancreatic fistula in patients undergoing distal pancreatectomy: A review of 294 consecutive cases.

PubMed

Sell, Naomi M; Pucci, Michael J; Gabale, Salil; Leiby, Benjamin E; Rosato, Ernest L; Winter, Jordan M; Yeo, Charles J; Lavu, Harish

2015-06-01

Pancreatic fistula (PF) is a significant cause of morbidity in patients undergoing distal pancreatectomy (DP), with an incidence of 15-40%. It remains unclear if the location of pancreatic transection affects the rate of PF occurrence. This study examines the correlation between the transection site of the pancreas during DP and the incidence of PF. All cases of DP from October 2005 to January 2012 were reviewed retrospectively from an institutional review board-approved database at the Thomas Jefferson University Hospital. Patient demographics and perioperative outcomes were analyzed. The pancreatic transection location was determined by review of operative reports, and then dichotomized into 2 groups: neck/body or tail. PF were graded following the International Study Group on Pancreatic Fistula guidelines. During the study period, 294 DP were performed with 244 pancreas transections at the neck/body and 50 at the tail. Of the 294 patients, 52 (17.7%) developed a postoperative PF. The incidence of PF after transection at the tail of the pancreas was higher (28%) when compared with transection at the neck/body (15.6%; P = .04). When stratified by PF grade, grade A PF occurred more commonly when transection of the gland was at the tail (22% tail vs 8.2% neck/body; P = .007); however, no difference was found for grade B/C PF (6% tail vs 7.4% neck/body; P = 1). Our data suggest that PF occurs more often when the tail is transected during DP, although the majority are low grade and of minimal clinical significance. More severe PF occurred equally between the transection sites. Copyright © 2015 Elsevier Inc. All rights reserved.

Video-Stimulated Accounts: Young Children Accounting for Interactional Matters in Front of Peers

ERIC Educational Resources Information Center

Theobald, Maryanne

2012-01-01

Research in the early years places increasing importance on participatory methods to engage children. The playback of video-recording to stimulate conversation is a research method that enables children's accounts to be heard and attends to a participatory view. During video-stimulated sessions, participants watch an extract of video-recording of…

The time course of taste bud regeneration after glossopharyngeal or greater superficial petrosal nerve transection in rats.

PubMed

St John, Steven J; Garcea, Mircea; Spector, Alan C

2003-01-01

We previously have published data detailing the time course of taste bud regeneration in the anterior tongue following transection of the chorda tympani (CT) nerve in the rat. This study extends the prior work by determining the time course of taste bud regeneration in the vallate papilla, soft palate and nasoincisor ducts (NID) following transection of either the glossopharyngeal (GL) or greater superficial petrosal (GSP) nerve. Following GL transection in rats (n = 6 per time point), taste buds reappeared in the vallate papilla between 15 and 28 days after surgery, and returned to 80.3% of control levels (n = 12) of taste buds by 70 days postsurgery. The first appearance and the final percentage of the normal complement of regenerated vallate taste buds after GL transection resembled that seen previously in the anterior tongue after CT transection. However, in the latter case, regenerated taste buds reached asymptotic levels by 42 days after surgery, whereas within the time frame of the present study, a clear asymptotic return of vallate taste buds was not observed. In contrast to the posterior (and anterior) tongue, only 25% of the normal complement of palatal taste buds regenerated by 112 days and 224 days after GSP transection (n = 9). The difference in regenerative capacity might relate to the surgical approach used to transect the GSP. These experiments provide useful parametric data for investigators studying the functional consequences of gustatory nerve transection and regeneration.

Monte Carlo approaches to sampling forested tracts with lines or points

Treesearch

Harry T. Valentine; Jeffrey H. Gove; Timothy G. Gregoire

2001-01-01

Several line- and point-based sampling methods can be employed to estimate the aggregate dimensions of trees standing on a forested tract or pieces of coarse woody debris lying on the forest floor. Line methods include line intersect sampling, horizontal line sampling, and transect relascope sampling; point methods include variable- and fixed-radius plot sampling, and...

The Relationship Between Method of Viewing Lectures, Course Ratings, and Course Timing.

PubMed

Burton, William B; Ma, Terence P; Grayson, Martha S

2017-01-01

In recent years, medical schools have provided students access to video recordings of course lectures, but few studies have investigated the impact of this on ratings of courses and teachers. This study investigated whether the method of viewing lectures was related to student ratings of the course and its components and whether the method used changed over time. Preclinical medical students indicated whether ratings of course lectures were based primarily on lecture attendance, video capture, or both. Students were categorized into Lecture, Video, or Both groups based on their responses to this question. The data consisted of 7584 student evaluations collected over 2 years. Students who attended live lectures rated the course and its components higher than students who only viewed the video or used both methods, although these differences were very small. Students increasingly watched lectures exclusively by video over time: in comparison with first-year students, second-year students were more likely to watch lectures exclusively by video; in comparison with students in the first half of the academic year, students in the second half of the academic year were more likely to watch lectures exclusively by video. With the increase in use of lecture video recordings across medical schools, attention must be paid to student attitudes regarding these methods.

An automatic method to calculate heart rate from zebrafish larval cardiac videos.

PubMed

Kang, Chia-Pin; Tu, Hung-Chi; Fu, Tzu-Fun; Wu, Jhe-Ming; Chu, Po-Hsun; Chang, Darby Tien-Hao

2018-05-09

Zebrafish is a widely used model organism for studying heart development and cardiac-related pathogenesis. With the ability of surviving without a functional circulation at larval stages, strong genetic similarity between zebrafish and mammals, prolific reproduction and optically transparent embryos, zebrafish is powerful in modeling mammalian cardiac physiology and pathology as well as in large-scale high throughput screening. However, an economical and convenient tool for rapid evaluation of fish cardiac function is still in need. There have been several image analysis methods to assess cardiac functions in zebrafish embryos/larvae, but they are still improvable to reduce manual intervention in the entire process. This work developed a fully automatic method to calculate heart rate, an important parameter to analyze cardiac function, from videos. It contains several filters to identify the heart region, to reduce video noise and to calculate heart rates. The proposed method was evaluated with 32 zebrafish larval cardiac videos that were recording at three-day post-fertilization. The heart rate measured by the proposed method was comparable to that determined by manual counting. The experimental results show that the proposed method does not lose accuracy while largely reducing the labor cost and uncertainty of manual counting. With the proposed method, researchers do not have to manually select a region of interest before analyzing videos. Moreover, filters designed to reduce video noise can alleviate background fluctuations during the video recording stage (e.g. shifting), which makes recorders generate usable videos easily and therefore reduce manual efforts while recording.

Review of passive-blind detection in digital video forgery based on sensing and imaging techniques

NASA Astrophysics Data System (ADS)

Tao, Junjie; Jia, Lili; You, Ying

2016-01-01

Advances in digital video compression and IP communication technologies raised new issues and challenges concerning the integrity and authenticity of surveillance videos. It is so important that the system should ensure that once recorded, the video cannot be altered; ensuring the audit trail is intact for evidential purposes. This paper gives an overview of passive techniques of Digital Video Forensics which are based on intrinsic fingerprints inherent in digital surveillance videos. In this paper, we performed a thorough research of literatures relevant to video manipulation detection methods which accomplish blind authentications without referring to any auxiliary information. We presents review of various existing methods in literature, and much more work is needed to be done in this field of video forensics based on video data analysis and observation of the surveillance systems.

Healthcare personnel's experiences using video consultation in primary healthcare in rural areas.

PubMed

Johansson, Annette M; Lindberg, Inger; Söderberg, Siv

2017-01-01

Patients living in rural areas often need to travel long distances for access to specialist care. To increase access to specialist care, video consultation between patients in primary healthcare and specialist care has been used. In order for this new method to be developed and used to the fullest, it is important to understand healthcare personnel's experiences with this intervention. The aim of this study was to describe healthcare personnel's experiences using video consultation in their work in primary healthcare. A mixed methods design was used, and the data were analysed using qualitative and quantitative analysis methods. Interviews were conducted with eight general practitioners and one district nurse, all of whom had conducted a video consultation with a patient and a specialist physician or a cardiac specialist nurse. After each video consultation, the participants completed a consultation report/questionnaire. Healthcare personnel considered video consultation to provide quicker access to specialist care for the patient, and greater security when the video consultation encounter was conducted at their own primary healthcare centre. They considered video consultation an opportunity to provide education and for the patients to ask questions. Video consultation is a satisfactory tool for healthcare personnel, and the technology is a new, useful method, especially for the district nurses. Further, video consultation is an opportunity for healthcare personnel to learn. However, for it to work as an accepted method, the technology must function well and be user friendly. It must also be clear that it is beneficial for the patients and the healthcare personnel.

Initiating or blocking locomotion in spinal cats by applying noradrenergic drugs to restricted lumbar spinal segments.

PubMed

Marcoux, J; Rossignol, S

2000-11-15

After an acute low thoracic spinal transection (T13), cats can be made to walk with the hindlimbs on a treadmill with clonidine, an alpha2-noradrenergic agonist. Because previous studies of neonatal rat spinal cord in vitro suggest that the most important lumbar segments for rhythmogenesis are L1-L2, we investigated the role of various lumbar segments in the initiation of walking movements on a treadmill of adult cats spinalized (T13), 5-6 d earlier. The locomotor activities were evaluated from electromyographic and video recordings. The results show that: (1) localized topical application of clonidine in restricted baths over either the L3-L4 or the L5-L7 segments was sufficient to induce walking movements. Yohimbine, an alpha2-noradrenergic antagonist, could block this locomotion when applied over L3-L4 or L5-L7; (2) microinjections of clonidine in one or two lumbar segments from L3 to L5 could also induce locomotion; (3) after an intravenous injection of clonidine, locomotion was blocked by microinjections of yohimbine in segments L3, L4, or L5 but not if the injection was in L6; (4) locomotion was also blocked in all cases by additional spinal transections at L3 or L4. These results show that it is possible to initiate walking in the adult spinal cat with a pharmacological stimulation of a restricted number of lumbar segments and also that the integrity of the L3-L4 segments is necessary to sustain the locomotor activity.

Assessing instrument handling and operative consequences simultaneously: a simple method for creating synced multicamera videos for endosurgical or microsurgical skills assessments.

PubMed

Jabbour, Noel; Sidman, James

2011-10-01

There has been an increasing interest in assessment of technical skills in most medical and surgical disciplines. Many of these assessments involve microscopy or endoscopy and are thus amenable to video recording for post hoc review. An ideal skills assessment video would provide the reviewer with a simultaneous view of the examinee's instrument handling and the operative field. Ideally, a reviewer should be blinded to the identity of the examinee and whether the assessment was performed as a pretest or posttest examination, when given in conjunction with an educational intervention. We describe a simple method for reliably creating deidentified, multicamera, time-synced videos, which may be used in technical skills assessments. We pilot tested this method in a pediatric airway endoscopy Objective Assessment of Technical Skills (OSATS). Total video length was compared with the OSATS administration time. Thirty-nine OSATS were administered. There were no errors encountered in time-syncing the videos using this method. Mean duration of OSATS videos was 11 minutes and 20 seconds, which was significantly less than the time needed for an expert to be present at the administration of each 30-minute OSATS (P < 0.001). The described method for creating time-synced, multicamera skills assessment videos is reliable and may be used in endosurgical or microsurgical skills assessments. Compared with live review, post hoc video review using this method can save valuable expert reviewer time. Most importantly, this method allows a reviewer to simultaneously evaluate an examinee's instrument handling and the operative field while being blinded to the examinee's identity and timing of examination administration.

Gamifying Video Object Segmentation.

PubMed

Spampinato, Concetto; Palazzo, Simone; Giordano, Daniela

2017-10-01

Video object segmentation can be considered as one of the most challenging computer vision problems. Indeed, so far, no existing solution is able to effectively deal with the peculiarities of real-world videos, especially in cases of articulated motion and object occlusions; limitations that appear more evident when we compare the performance of automated methods with the human one. However, manually segmenting objects in videos is largely impractical as it requires a lot of time and concentration. To address this problem, in this paper we propose an interactive video object segmentation method, which exploits, on one hand, the capability of humans to identify correctly objects in visual scenes, and on the other hand, the collective human brainpower to solve challenging and large-scale tasks. In particular, our method relies on a game with a purpose to collect human inputs on object locations, followed by an accurate segmentation phase achieved by optimizing an energy function encoding spatial and temporal constraints between object regions as well as human-provided location priors. Performance analysis carried out on complex video benchmarks, and exploiting data provided by over 60 users, demonstrated that our method shows a better trade-off between annotation times and segmentation accuracy than interactive video annotation and automated video object segmentation approaches.

Postoperative occipital neuralgia with and without C2 nerve root transection during atlantoaxial screw fixation: a post-hoc comparative outcome study of prospectively collected data.

PubMed

Yeom, Jin S; Buchowski, Jacob M; Kim, Ho-Joong; Chang, Bong-Soon; Lee, Choon-Ki; Riew, K Daniel

2013-07-01

Although routine transection of the C2 nerve root during atlantoaxial segmental screw fixation has been recommended by some surgeons, it remains controversial and to our knowledge no comparative studies have been performed to determine whether transection or preservation of the C2 nerve root affects patient-derived sensory outcomes. The purpose of this study is to specifically analyze patient-derived sensory outcomes over time in patients with intentional C2 nerve root transection during atlantoaxial segmental screw fixation compared with those without transection. This is a post-hoc comparative analysis of prospectively collected patient-derived outcome data. The sample consists of 24 consecutive patients who underwent intentional bilateral transection of the C2 nerve root during posterior atlantoaxial segmental screw fixation (transection group) and subsequent 41 consecutive patients without transection (preservation group). A visual analog scale (VAS) score was used for occipital neuralgia as the primary outcome measure and VAS score for neck pain, neck disability index score and Japanese Orthopedic Association score for cervical myelopathy and recovery rate, with bone union rate as the secondary outcome measure. Patient-derived outcomes including change in VAS score for occipital neuralgia over time were statistically compared between the two groups. This study was not supported by any financial sources and there is no topic-specific conflict of interest related to the authors of this study. Seven (29%) of the 24 patients in the transection group experienced increased neuralgic pain at 1 month after surgery either because of newly developed occipital neuralgia or aggravation of preexisting occipital neuralgia. Four of the seven patients required almost daily medication even at the final follow-up (44 and 80 months). On the other hand, only four (10%) of 41 patients in the preservation group had increased neuralgic pain at 1 month after surgery, and at ≥ 1 year, no patients had increased neuralgic pain. The difference in the prevalence of increased neuralgic pain between the two groups was statistically significant at all time points (3, 6, 12, and 24 months postoperatively) except at 1 month postoperatively. The intensity of neuralgic pain, which preoperatively had not been significantly different between the two groups, was significantly higher in the transection group at the final follow-up. C2 nerve root transection is not a benign procedure and, in our experience, more than a quarter of the patients experience increased neuralgic pain following C2 nerve root transection. Because the prevalence and intensity of postoperative neuralgia was significantly higher with C2 nerve root transection than with its preservation, we recommend against routine C2 nerve root transection when performing atlantoaxial segmental screw fixation. Copyright © 2013 Elsevier Inc. All rights reserved.

Continental-scale patterns in soil geochemistry and mineralogy: results from two transects across the United States and Canada

USGS Publications Warehouse

Woodruff, L.G.; Cannon, W.F.; Eberl, D.D.; Smith, D.B.; Kilburn, J.E.; Horton, J.D.; Garrett, R.G.; Klassen, R.A.

2009-01-01

In 2004, the US Geological Survey (USGS) and the Geological Survey of Canada (GSC) initiated a pilot study that involved collection of more than 1500 soil samples from 221 sites along two continental transects across Canada and the United States. The pilot study was designed to test and refine protocols for a soil geochemical survey of North America. The two transects crossed a wide array of soil parent materials, soil ages, climatic conditions, landforms, land covers and land uses. Sample sites were selected randomly at approximately 40-km intervals from a population defined as all soils of the continent. At each site, soils representing 0 to 5 cm depth, and the O, A, and C horizons, if present, were collected and analyzed for their near-total content of over 40 major and trace elements. Soils from 0–5 cm depth were also collected for analysis of organic compounds. Results from the transects confirm that soil samples collected at a 40-km spacing reveal coherent, continental- to subcontinental-scale geochemical and mineralogical patterns that can be correlated to aspects of underlying soil parent material, soil age and climate influence. The geochemical data also demonstrate that at the continental-scale the dominance of any of these major factors that control soil geochemistry can change across the landscape. Along both transects, soil mineralogy and geochemistry change abruptly with changes in soil parent materials. However, the chemical influence of a soil’s parent material can be obscured by changing climatic conditions. For the transects, increasing precipitation from west to east and increasing temperature from north to south affect both soil mineralogy and geochemistry because of climate effects on soil weathering and leaching, and plant productivity. Regional anomalous metal concentrations can be linked to natural variations in soil parent materials, such as high Ni and Cr in soils developed on ultramafic rocks in California or high P in soils formed on weathered Ordovician limestones in central Kentucky. On local scales, anomalous metal concentrations recognized in soil profiles, such as high P in soils from animal confinement sites, are consistent with local anthropogenic disturbances. At a larger scale, the distribution of Hg across the west to east transect demonstrates that it can be difficult to distinguish between natural or anthropogenic contributions and that many factors can contribute to an element’s spatial distribution. Only three samples in a subset of seventy-three 0–5 cm depth soil samples from the north to south transect had organochlorine pesticides values above the method detection limit, apparently related to historic usage of the pesticides DDT and dieldrin.

A structural transect across the Mongolian Western Altai: Active transpressional mountain building in central Asia

NASA Astrophysics Data System (ADS)

Dickson Cunningham, W.; Windley, Brian F.; Dorjnamjaa, D.; Badamgarov, G.; Saandar, M.

1996-02-01

We present results from the first detailed geological transect across the Mongolian Western Altai using modern methods of structural geology and fault kinematic analysis. Our purpose was to document the structures responsible for Cenozoic uplift of the range in order to better understand processes of intracontinental mountain building. Historical right-lateral strike-slip and oblique-slip earthquakes have previously been documented from the Western Altai, and many mountain fronts are marked by active fault scarps indicating current tectonic activity and uplift. The dominant structures in the range are long (>200 km) NNW trending right-lateral strike-slip faults. Our transect can be divided into three separate domains that contain active, right-lateral strike-slip master faults and thrust faults with opposing vergence. The current deformation regime is thus transpressional. Each domain has an asymmetric flower structure cross-sectional geometry, and the transect as a whole is interpreted as three separate large flower structures. The mechanism of uplift along the transect appears to be horizontal and vertical growth of flower structures rooted into the dominant right-lateral strike-slip faults. The major Bulgan Fault forms the southern structural boundary to the range and is a 3.5-km-wide brittle-ductile zone that has accommodated reverse and left-lateral strike-slip displacements. It appears to be linked to the North Gobi Fault Zone to the east and Irtysh Fault zone to the west and thus may be over 900 km in length. Two major ductile left-lateral extensional shear zones were identified in the interior of the range that appear to be preserved structures related to a regional Paleozoic or Mesozoic extensional event. Basement rocks along the transect are dominantly metavolcanic, metasedimentary, or intrusive units probably representing a Paleozoic accretionary prism and arc complex. The extent to which Cenozoic uplift has been accommodated by reactivation of older structures and inversion of older basins is unknown and will require further study. As previously suggested by others, Cenozoic uplift of the Altai is interpreted to be due to NE-SW directed compressional stress resulting from the Indo-Eurasian collision 2500 km to the south.

Effects of observers using different methods upon the total population estimates of two resident island birds

Treesearch

Sheila Conant; Mark S. Collins; C. John Ralph

1981-01-01

During a 5-week study of the Nihoa Millerbird and Nihoa Finch, we censused birds using these techniques: two line transect methods, a variable-distance circular plot method, and spot-mapping of territories (millerbirds only). Densities derived from these methods varied greatly. Due to differences in behavior, it appeared that the two species reacted differently to the...

Effect of luminal contents on postresectional longitudinal and mucosal growth in the ileum of suckling rats.

PubMed

Ford, W D; de Vries, J E; Ross, J S; Malt, R A

1985-11-01

Effects of luminal contents on adaptive growth of the ileum in the neonatal small bowel of rats were examined after resection of the proximal small bowel and after removal of the ileum from the enteric stream. Four weeks after resection of the proximal 60% of the small bowel in 10-day-old rats, the distal 40% of the small bowel elongated by 281%. This distal segment also elongated by 265% after intestinal transection (p greater than 0.05), but by only 191% when it was bypassed (bypass versus resection or transection, p less than 0.001). After resection the distal villi were 81% taller, but after transection they were only 19% taller (p less than 0.001 versus resection); after bypass they did not grow (p less than 0.001 versus resection or transection). The distal crypts were 404% deeper after resection, 331% deeper after transection (p less than 0.05), and 291% deeper after bypass (p less than 0.001 versus resection, p greater than 0.05 versus transection). The DNA content was 517% greater after resection, 364% greater after transection (p less than 0.001), and 73% greater after bypass (p less than 0.001 versus transection or resection). Maximal elongation of the small bowel occurs in the presence of luminal nutrition. Increasing luminal nutrition is associated with increasing mucosal hyperplasia.

Shrinkage of ipsilateral taste buds and hyperplasia of contralateral taste buds following chorda tympani nerve transection.

PubMed

Li, Yi-Ke; Yang, Juan-Mei; Huang, Yi-Bo; Ren, Dong-Dong; Chi, Fang-Lu

2015-06-01

The morphological changes that occur in the taste buds after denervation are not well understood in rats, especially in the contralateral tongue epithelium. In this study, we investigated the time course of morphological changes in the taste buds following unilateral nerve transection. The role of the trigeminal component of the lingual nerve in maintaining the structural integrity of the taste buds was also examined. Twenty-four Sprague-Dawley rats were randomly divided into three groups: control, unilateral chorda tympani nerve transection and unilateral chorda tympani nerve transection + lingual nerve transection. Rats were allowed up to 42 days of recovery before being euthanized. The taste buds were visualized using a cytokeratin 8 antibody. Taste bud counts, volumes and taste receptor cell numbers were quantified and compared among groups. No significant difference was detected between the chorda tympani nerve transection and chorda tympani nerve transection + lingual nerve transection groups. Taste bud counts, volumes and taste receptor cell numbers on the ipsilateral side all decreased significantly compared with control. On the contralateral side, the number of taste buds remained unchanged over time, but they were larger, and taste receptor cells were more numerous postoperatively. There was no evidence for a role of the trigeminal branch of the lingual nerve in maintaining the structural integrity of the anterior taste buds.

Neuroprotective effects of (-)-epigallocatechin-3-gallate (EGCG) against peripheral nerve transection-induced apoptosis.

PubMed

Kian, Kosar; Khalatbary, Ali Reza; Ahmadvand, Hassan; Karimpour Malekshah, Abbasali; Shams, Zahra

2018-01-02

Recent studies revealed the neuroprotective effects of epigallocatechin-3-gallate (EGCG) on a variety of neural injury models. The purpose of this study was to determine the neuroprotective effects of EGCG following sciatic nerve transection (SNT). Rats were randomly divided into four groups each as follows: Sham-operated group, SNT group, and Pre-EGCG (50-mg/kg, i.p., 30 minutes before nerve transection and followed for 3 days) and Post-EGCG (50-mg/kg, i.p., 1 hour after nerve transection and followed for 3 days) groups. Spinal cord segments of the sciatic nerve and related dorsal root ganglions were removed four weeks after nerve transection for the assessment of malondialdehyde (MDA) levels, superoxide dismutase (SOD) and catalase (CAT) activities, immunohistochemistry of caspase-3, cyclooxygenase-2 (COX-2), S100beta (S100B), and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). MDA levels were significantly decreased, and SOD and CAT activities were significantly increased in EGCG-treated rats after nerve transection. Attenuated caspase-3 and COX-2 expression, and TUNEL reaction could be significantly detected in the EGCG-treated rats after nerve transection. Also, EGCG significantly increased S100B expression. We propose that EGCG may be effective in the protection of neuronal cells against retrograde apoptosis and may enhance neuronal survival time following nerve transection.

No-Reference Video Quality Assessment Based on Statistical Analysis in 3D-DCT Domain.

PubMed

Li, Xuelong; Guo, Qun; Lu, Xiaoqiang

2016-05-13

It is an important task to design models for universal no-reference video quality assessment (NR-VQA) in multiple video processing and computer vision applications. However, most existing NR-VQA metrics are designed for specific distortion types which are not often aware in practical applications. A further deficiency is that the spatial and temporal information of videos is hardly considered simultaneously. In this paper, we propose a new NR-VQA metric based on the spatiotemporal natural video statistics (NVS) in 3D discrete cosine transform (3D-DCT) domain. In the proposed method, a set of features are firstly extracted based on the statistical analysis of 3D-DCT coefficients to characterize the spatiotemporal statistics of videos in different views. These features are used to predict the perceived video quality via the efficient linear support vector regression (SVR) model afterwards. The contributions of this paper are: 1) we explore the spatiotemporal statistics of videos in 3DDCT domain which has the inherent spatiotemporal encoding advantage over other widely used 2D transformations; 2) we extract a small set of simple but effective statistical features for video visual quality prediction; 3) the proposed method is universal for multiple types of distortions and robust to different databases. The proposed method is tested on four widely used video databases. Extensive experimental results demonstrate that the proposed method is competitive with the state-of-art NR-VQA metrics and the top-performing FR-VQA and RR-VQA metrics.

Using Mixed Methods to Analyze Video Data: A Mathematics Teacher Professional Development Example

ERIC Educational Resources Information Center

DeCuir-Gunby, Jessica T.; Marshall, Patricia L.; McCulloch, Allison W.

2012-01-01

This article uses data from 65 teachers participating in a K-2 mathematics professional development research project as an example of how to analyze video recordings of teachers' classroom lessons using mixed methods. Through their discussion, the authors demonstrate how using a mixed methods approach to classroom video analysis allows researchers…

Video denoising using low rank tensor decomposition

NASA Astrophysics Data System (ADS)

Gui, Lihua; Cui, Gaochao; Zhao, Qibin; Wang, Dongsheng; Cichocki, Andrzej; Cao, Jianting

2017-03-01

Reducing noise in a video sequence is of vital important in many real-world applications. One popular method is block matching collaborative filtering. However, the main drawback of this method is that noise standard deviation for the whole video sequence is known in advance. In this paper, we present a tensor based denoising framework that considers 3D patches instead of 2D patches. By collecting the similar 3D patches non-locally, we employ the low-rank tensor decomposition for collaborative filtering. Since we specify the non-informative prior over the noise precision parameter, the noise variance can be inferred automatically from observed video data. Therefore, our method is more practical, which does not require knowing the noise variance. The experimental on video denoising demonstrates the effectiveness of our proposed method.

Attenuation of TRPV1 by AMG-517 after nerve injury promotes peripheral axonal regeneration in rats.

PubMed

Bai, Juan; Liu, Fu; Wu, Li-Fei; Wang, Ya-Fang; Li, Xia-Qing

2018-01-01

Aims The main objective was to investigate the effects of the transient receptor potential cation channel subfamily V member 1 (TRPV1) on nerve regeneration following sciatic transection injury by functional blockage of TRPV1 using AMG-517, a specific blocker of TRPV1. Methods AMG-517 was injected into the area surrounding ipsilateral lumbar dorsal root ganglia 30 min after unilateral sciatic nerve transection. The number of sciatic axons and the expression of growth-associated protein-43 (GAP-43) and glial fibrillary acidic protein was examined using semithin sections, Western blot, and immunofluorescence analyses. Results Blockage of TRPV1 with AMG-517 markedly promoted axonal regeneration, especially at two weeks after sciatic injury; the number of axons was similar to the uninjured control group. After sciatic nerve transection, expression of glial fibrillary acidic protein was decreased and GAP-43 was increased at the proximal stump. However, the expression of both glial fibrillary acidic protein and GAP-43 increased significantly in AMG-517-treated groups. Conclusions TRPV1 may be an important therapeutic target to promote peripheral nerve regeneration after injury.

Modeling abundance using hierarchical distance sampling

USGS Publications Warehouse

Royle, Andy; Kery, Marc

2016-01-01

In this chapter, we provide an introduction to classical distance sampling ideas for point and line transect data, and for continuous and binned distance data. We introduce the conditional and the full likelihood, and we discuss Bayesian analysis of these models in BUGS using the idea of data augmentation, which we discussed in Chapter 7. We then extend the basic ideas to the problem of hierarchical distance sampling (HDS), where we have multiple point or transect sample units in space (or possibly in time). The benefit of HDS in practice is that it allows us to directly model spatial variation in population size among these sample units. This is a preeminent concern of most field studies that use distance sampling methods, but it is not a problem that has received much attention in the literature. We show how to analyze HDS models in both the unmarked package and in the BUGS language for point and line transects, and for continuous and binned distance data. We provide a case study of HDS applied to a survey of the island scrub-jay on Santa Cruz Island, California.

Forest Soil Disturbance Monitoring Protocol: Volume II: Supplementary methods, statistics, and data collection

Treesearch

Deborah S. Page-Dumroese; Ann M. Abbott; Thomas M. Rice

2009-01-01

Volume I and volume II of the Forest Soil Disturbance Monitoring Protocol (FSDMP) provide information for a wide range of users, including technicians, field crew leaders, private landowners, land managers, forest professionals, and researchers. Volume I: Rapid Assessment includes the basic methods for establishing forest soil monitoring transects and consistently...

New methods for sampling sparse populations

Treesearch

Anna Ringvall

2007-01-01

To improve surveys of sparse objects, methods that use auxiliary information have been suggested. Guided transect sampling uses prior information, e.g., from aerial photographs, for the layout of survey strips. Instead of being laid out straight, the strips will wind between potentially more interesting areas. 3P sampling (probability proportional to prediction) uses...

Point Intercept (PO)

Treesearch

John F. Caratti

2006-01-01

The FIREMON Point Intercept (PO) method is used to assess changes in plant species cover or ground cover for a macroplot. This method uses a narrow diameter sampling pole or sampling pins, placed at systematic intervals along line transects to sample within plot variation and quantify statistically valid changes in plant species cover and height over time. Plant...

Video-based face recognition via convolutional neural networks

NASA Astrophysics Data System (ADS)

Bao, Tianlong; Ding, Chunhui; Karmoshi, Saleem; Zhu, Ming

2017-06-01

Face recognition has been widely studied recently while video-based face recognition still remains a challenging task because of the low quality and large intra-class variation of video captured face images. In this paper, we focus on two scenarios of video-based face recognition: 1)Still-to-Video(S2V) face recognition, i.e., querying a still face image against a gallery of video sequences; 2)Video-to-Still(V2S) face recognition, in contrast to S2V scenario. A novel method was proposed in this paper to transfer still and video face images to an Euclidean space by a carefully designed convolutional neural network, then Euclidean metrics are used to measure the distance between still and video images. Identities of still and video images that group as pairs are used as supervision. In the training stage, a joint loss function that measures the Euclidean distance between the predicted features of training pairs and expanding vectors of still images is optimized to minimize the intra-class variation while the inter-class variation is guaranteed due to the large margin of still images. Transferred features are finally learned via the designed convolutional neural network. Experiments are performed on COX face dataset. Experimental results show that our method achieves reliable performance compared with other state-of-the-art methods.

Joint Attributes and Event Analysis for Multimedia Event Detection.

PubMed

Ma, Zhigang; Chang, Xiaojun; Xu, Zhongwen; Sebe, Nicu; Hauptmann, Alexander G

2017-06-15

Semantic attributes have been increasingly used the past few years for multimedia event detection (MED) with promising results. The motivation is that multimedia events generally consist of lower level components such as objects, scenes, and actions. By characterizing multimedia event videos with semantic attributes, one could exploit more informative cues for improved detection results. Much existing work obtains semantic attributes from images, which may be suboptimal for video analysis since these image-inferred attributes do not carry dynamic information that is essential for videos. To address this issue, we propose to learn semantic attributes from external videos using their semantic labels. We name them video attributes in this paper. In contrast with multimedia event videos, these external videos depict lower level contents such as objects, scenes, and actions. To harness video attributes, we propose an algorithm established on a correlation vector that correlates them to a target event. Consequently, we could incorporate video attributes latently as extra information into the event detector learnt from multimedia event videos in a joint framework. To validate our method, we perform experiments on the real-world large-scale TRECVID MED 2013 and 2014 data sets and compare our method with several state-of-the-art algorithms. The experiments show that our method is advantageous for MED.

Relative spatial soil geochemical variability along two transects across the United States and Canada

USGS Publications Warehouse

Garrett, Robert G.

2009-01-01

The patterns of relative variability differ by transect and horizon. The N–S transect A-horizon soils show significant between-40-km scale variability for 29 elements, with only 4 elements (Ca, Mg, Pb and Sr) showing in excess of 50% of their variability at the within-40-km and ‘at-site’ scales. In contrast, the C-horizon data demonstrate significant between-40-km scale variability for 26 elements, with 21 having in excess of 50% of their variability at the within-40-km and ‘at-site’ scales. In 36 instances, the ‘at-site’ variability is statistically significant in terms of the sample preparation and analysis variability. It is postulated that this contrast between the A- and C- horizons along the N–S transect, that is dominated by agricultural land uses, is due to the local homogenization of Ap-horizon soils by tillage reducing the ‘at-site’ variability. The spatial variability is distributed similarly between scales for the A- and C-horizon soils of the E–W transect. For all elements, there is significant variability at the within-40-km scale. Notwithstanding this, there is significant between-40-km variability for 28 and 20 of the elements in the A- and C-horizon data, respectively. The differences between the two transects are attributed to (1) geology, the N–S transect runs generally parallel to regional strikes, whereas the E–W transect runs across regional structures and lithologies; and (2) land use, with agricultural tillage dominating along the N–S transect. The spatial analysis of the transect data indicates that continental-scale maps demonstrating statistically significant patterns of geochemical variability may be prepared for many elements from data on soil samples collected on a 40 x 40 km grid or similar sampling designs resulting in a sample density of 1 site per 1600 km2.

Method and apparatus for reading meters from a video image

DOEpatents

Lewis, Trevor J.; Ferguson, Jeffrey J.

1997-01-01

A method and system to enable acquisition of data about an environment from one or more meters using video images. One or more meters are imaged by a video camera and the video signal is digitized. Then, each region of the digital image which corresponds to the indicator of the meter is calibrated and the video signal is analyzed to determine the value indicated by each meter indicator. Finally, from the value indicated by each meter indicator in the calibrated region, a meter reading is generated. The method and system offer the advantages of automatic data collection in a relatively non-intrusive manner without making any complicated or expensive electronic connections, and without requiring intensive manpower.

Hypothalamic network for thermoregulatory shivering.

PubMed

Kanosue, K; Zhang, Y H; Yanase-Fujiwara, M; Hosono, T

1994-07-01

Warming one side of a rat's preoptic area and anterior hypothalamus (POAH) suppresses shivering on both sides of the body, and the present study evaluated the extent to which signals mediating this suppression cross the midline within and below the POAH. Hind paw shivering during unilateral POAH thermal stimulation was measured for rats in which the POAH had been midsagittally transected and for rats in which one side of the hypothalamus had been coronally transected just caudal to the POAH. In midsagittally transected rats, unilateral warming on either side of the POAH suppressed shivering equally on both sides of the body. In unilaterally transected rats, POAH warming on the transected side did not affect shivering, but warming the intact side suppressed shivering equally on both sides of the body. When a unilateral transection of only the lateral part of the hypothalamus included the medial forebrain bundle, the effect was the same as that of a unilateral transection of the whole hypothalamus. These results indicate that no information controlling shivering is exchanged between the left and right POAH and that efferent signals from the POAH, descending through the medial forebrain bundle, cross the midline somewhere below the hypothalamus to innervate both sides of the body equally.

Video quality pooling adaptive to perceptual distortion severity.

PubMed

Park, Jincheol; Seshadrinathan, Kalpana; Lee, Sanghoon; Bovik, Alan Conrad

2013-02-01

It is generally recognized that severe video distortions that are transient in space and/or time have a large effect on overall perceived video quality. In order to understand this phenomena, we study the distribution of spatio-temporally local quality scores obtained from several video quality assessment (VQA) algorithms on videos suffering from compression and lossy transmission over communication channels. We propose a content adaptive spatial and temporal pooling strategy based on the observed distribution. Our method adaptively emphasizes "worst" scores along both the spatial and temporal dimensions of a video sequence and also considers the perceptual effect of large-area cohesive motion flow such as egomotion. We demonstrate the efficacy of the method by testing it using three different VQA algorithms on the LIVE Video Quality database and the EPFL-PoliMI video quality database.

A Benchmark and Comparative Study of Video-Based Face Recognition on COX Face Database.

PubMed

Huang, Zhiwu; Shan, Shiguang; Wang, Ruiping; Zhang, Haihong; Lao, Shihong; Kuerban, Alifu; Chen, Xilin

2015-12-01

Face recognition with still face images has been widely studied, while the research on video-based face recognition is inadequate relatively, especially in terms of benchmark datasets and comparisons. Real-world video-based face recognition applications require techniques for three distinct scenarios: 1) Videoto-Still (V2S); 2) Still-to-Video (S2V); and 3) Video-to-Video (V2V), respectively, taking video or still image as query or target. To the best of our knowledge, few datasets and evaluation protocols have benchmarked for all the three scenarios. In order to facilitate the study of this specific topic, this paper contributes a benchmarking and comparative study based on a newly collected still/video face database, named COX(1) Face DB. Specifically, we make three contributions. First, we collect and release a largescale still/video face database to simulate video surveillance with three different video-based face recognition scenarios (i.e., V2S, S2V, and V2V). Second, for benchmarking the three scenarios designed on our database, we review and experimentally compare a number of existing set-based methods. Third, we further propose a novel Point-to-Set Correlation Learning (PSCL) method, and experimentally show that it can be used as a promising baseline method for V2S/S2V face recognition on COX Face DB. Extensive experimental results clearly demonstrate that video-based face recognition needs more efforts, and our COX Face DB is a good benchmark database for evaluation.

How the “Understanding Research Evidence” Web-Based Video Series From the National Collaborating Centre for Methods and Tools Contributes to Public Health Capacity to Practice Evidence-Informed Decision Making: Mixed-Methods Evaluation

PubMed Central

Chan, Linda; Mackintosh, Jeannie

2017-01-01

Background The National Collaborating Centre for Methods and Tools (NCCMT) offers workshops and webinars to build public health capacity for evidence-informed decision-making. Despite positive feedback for NCCMT workshops and resources, NCCMT users found key terms used in research papers difficult to understand. The Understanding Research Evidence (URE) videos use plain language, cartoon visuals, and public health examples to explain complex research concepts. The videos are posted on the NCCMT website and YouTube channel. Objective The first four videos in the URE web-based video series, which explained odds ratios (ORs), confidence intervals (CIs), clinical significance, and forest plots, were evaluated. The evaluation examined how the videos affected public health professionals’ practice. A mixed-methods approach was used to examine the delivery mode and the content of the videos. Specifically, the evaluation explored (1) whether the videos were effective at increasing knowledge on the four video topics, (2) whether public health professionals were satisfied with the videos, and (3) how public health professionals applied the knowledge gained from the videos in their work. Methods A three-part evaluation was conducted to determine the effectiveness of the first four URE videos. The evaluation included a Web-based survey, telephone interviews, and pretest and posttests, which evaluated public health professionals’ experience with the videos and how the videos affected their public health work. Participants were invited to participate in this evaluation through various open access, public health email lists, through informational flyers and posters at the Canadian Public Health Association (CPHA) conference, and through targeted recruitment to NCCMT’s network. Results In the Web-based surveys (n=46), participants achieved higher scores on the knowledge assessment questions from watching the OR (P=.04), CI (P=.04), and clinical significance (P=.05) videos but not the forest plot (P=.12) video, as compared with participants who had not watched the videos. The pretest and posttest (n=124) demonstrated that participants had a better understanding of forest plots (P<.001) and CIs (P<.001) after watching the videos. Due to small sample size numbers, there were insufficient pretest and posttest data to conduct meaningful analyses on the clinical significance and OR videos. Telephone interview participants (n=18) thought the videos’ use of animation, narration, and plain language was appropriate for people with different levels of understanding and learning styles. Participants felt that by increasing their understanding of research evidence, they could develop better interventions and design evaluations to measure the impact of public health initiatives. Conclusions Overall, the results of the evaluation showed that watching the videos resulted in an increase in knowledge, and participants had an overall positive experience with the URE videos. With increased competence in using the best available evidence, professionals are empowered to contribute to decisions that can improve health outcomes of communities. PMID:28958986

Characterizing the uncertainty of classification methods and its impact on the performance of crowdsourcing

NASA Astrophysics Data System (ADS)

Ribera, Javier; Tahboub, Khalid; Delp, Edward J.

2015-03-01

Video surveillance systems are widely deployed for public safety. Real-time monitoring and alerting are some of the key requirements for building an intelligent video surveillance system. Real-life settings introduce many challenges that can impact the performance of real-time video analytics. Video analytics are desired to be resilient to adverse and changing scenarios. In this paper we present various approaches to characterize the uncertainty of a classifier and incorporate crowdsourcing at the times when the method is uncertain about making a particular decision. Incorporating crowdsourcing when a real-time video analytic method is uncertain about making a particular decision is known as online active learning from crowds. We evaluate our proposed approach by testing a method we developed previously for crowd flow estimation. We present three different approaches to characterize the uncertainty of the classifier in the automatic crowd flow estimation method and test them by introducing video quality degradations. Criteria to aggregate crowdsourcing results are also proposed and evaluated. An experimental evaluation is conducted using a publicly available dataset.

Three-directional motion-compensation mask-based novel look-up table on graphics processing units for video-rate generation of digital holographic videos of three-dimensional scenes.

PubMed

Kwon, Min-Woo; Kim, Seung-Cheol; Kim, Eun-Soo

2016-01-20

A three-directional motion-compensation mask-based novel look-up table method is proposed and implemented on graphics processing units (GPUs) for video-rate generation of digital holographic videos of three-dimensional (3D) scenes. Since the proposed method is designed to be well matched with the software and memory structures of GPUs, the number of compute-unified-device-architecture kernel function calls can be significantly reduced. This results in a great increase of the computational speed of the proposed method, allowing video-rate generation of the computer-generated hologram (CGH) patterns of 3D scenes. Experimental results reveal that the proposed method can generate 39.8 frames of Fresnel CGH patterns with 1920×1080 pixels per second for the test 3D video scenario with 12,088 object points on dual GPU boards of NVIDIA GTX TITANs, and they confirm the feasibility of the proposed method in the practical application fields of electroholographic 3D displays.

Tactile Cueing for Target Acquisition and Identification

DTIC Science & Technology

2005-09-01

method of coding tactile information, and the method of presenting elevation information were studied. Results: Subjects were divided into video game experienced...VGP) subjects and non- video game (NVGP) experienced subjects. VGPs showed a significantly lower’ target acquisition time with the 12...that video game players performed better with the highest level of tactile resolution, while non- video game players performed better with simpler pattern and a lower resolution display.

Detection of goal events in soccer videos

NASA Astrophysics Data System (ADS)

Kim, Hyoung-Gook; Roeber, Steffen; Samour, Amjad; Sikora, Thomas

2005-01-01

In this paper, we present an automatic extraction of goal events in soccer videos by using audio track features alone without relying on expensive-to-compute video track features. The extracted goal events can be used for high-level indexing and selective browsing of soccer videos. The detection of soccer video highlights using audio contents comprises three steps: 1) extraction of audio features from a video sequence, 2) event candidate detection of highlight events based on the information provided by the feature extraction Methods and the Hidden Markov Model (HMM), 3) goal event selection to finally determine the video intervals to be included in the summary. For this purpose we compared the performance of the well known Mel-scale Frequency Cepstral Coefficients (MFCC) feature extraction method vs. MPEG-7 Audio Spectrum Projection feature (ASP) extraction method based on three different decomposition methods namely Principal Component Analysis( PCA), Independent Component Analysis (ICA) and Non-Negative Matrix Factorization (NMF). To evaluate our system we collected five soccer game videos from various sources. In total we have seven hours of soccer games consisting of eight gigabytes of data. One of five soccer games is used as the training data (e.g., announcers' excited speech, audience ambient speech noise, audience clapping, environmental sounds). Our goal event detection results are encouraging.

Selecting salient frames for spatiotemporal video modeling and segmentation.

PubMed

Song, Xiaomu; Fan, Guoliang

2007-12-01

We propose a new statistical generative model for spatiotemporal video segmentation. The objective is to partition a video sequence into homogeneous segments that can be used as "building blocks" for semantic video segmentation. The baseline framework is a Gaussian mixture model (GMM)-based video modeling approach that involves a six-dimensional spatiotemporal feature space. Specifically, we introduce the concept of frame saliency to quantify the relevancy of a video frame to the GMM-based spatiotemporal video modeling. This helps us use a small set of salient frames to facilitate the model training by reducing data redundancy and irrelevance. A modified expectation maximization algorithm is developed for simultaneous GMM training and frame saliency estimation, and the frames with the highest saliency values are extracted to refine the GMM estimation for video segmentation. Moreover, it is interesting to find that frame saliency can imply some object behaviors. This makes the proposed method also applicable to other frame-related video analysis tasks, such as key-frame extraction, video skimming, etc. Experiments on real videos demonstrate the effectiveness and efficiency of the proposed method.

Adaptive compressed sensing of multi-view videos based on the sparsity estimation

NASA Astrophysics Data System (ADS)

Yang, Senlin; Li, Xilong; Chong, Xin

2017-11-01

The conventional compressive sensing for videos based on the non-adaptive linear projections, and the measurement times is usually set empirically. As a result, the quality of videos reconstruction is always affected. Firstly, the block-based compressed sensing (BCS) with conventional selection for compressive measurements was described. Then an estimation method for the sparsity of multi-view videos was proposed based on the two dimensional discrete wavelet transform (2D DWT). With an energy threshold given beforehand, the DWT coefficients were processed with both energy normalization and sorting by descending order, and the sparsity of the multi-view video can be achieved by the proportion of dominant coefficients. And finally, the simulation result shows that, the method can estimate the sparsity of video frame effectively, and provides an active basis for the selection of compressive observation times. The result also shows that, since the selection of observation times is based on the sparsity estimated with the energy threshold provided, the proposed method can ensure the reconstruction quality of multi-view videos.

Surgical gesture classification from video and kinematic data.

PubMed

Zappella, Luca; Béjar, Benjamín; Hager, Gregory; Vidal, René

2013-10-01

Much of the existing work on automatic classification of gestures and skill in robotic surgery is based on dynamic cues (e.g., time to completion, speed, forces, torque) or kinematic data (e.g., robot trajectories and velocities). While videos could be equally or more discriminative (e.g., videos contain semantic information not present in kinematic data), they are typically not used because of the difficulties associated with automatic video interpretation. In this paper, we propose several methods for automatic surgical gesture classification from video data. We assume that the video of a surgical task (e.g., suturing) has been segmented into video clips corresponding to a single gesture (e.g., grabbing the needle, passing the needle) and propose three methods to classify the gesture of each video clip. In the first one, we model each video clip as the output of a linear dynamical system (LDS) and use metrics in the space of LDSs to classify new video clips. In the second one, we use spatio-temporal features extracted from each video clip to learn a dictionary of spatio-temporal words, and use a bag-of-features (BoF) approach to classify new video clips. In the third one, we use multiple kernel learning (MKL) to combine the LDS and BoF approaches. Since the LDS approach is also applicable to kinematic data, we also use MKL to combine both types of data in order to exploit their complementarity. Our experiments on a typical surgical training setup show that methods based on video data perform equally well, if not better, than state-of-the-art approaches based on kinematic data. In turn, the combination of both kinematic and video data outperforms any other algorithm based on one type of data alone. Copyright © 2013 Elsevier B.V. All rights reserved.

The conservation value of degraded forests for agile gibbons Hylobates agilis.

PubMed

Lee, David C; Powell, Victoria J; Lindsell, Jeremy A

2015-01-01

All gibbon species are globally threatened with extinction yet conservation efforts are undermined by a lack of population and ecological data. Agile gibbons (Hylobates agilis) occur in Sumatra, Indonesia and adjacent mainland Southeast Asia. Population densities are known from four sites (three in Sumatra) while little is known about their ability to tolerate habitat degradation. We conducted a survey of agile gibbons in Harapan Rainforest, a lowland forest site in Sumatra. The area has been severely degraded by selective logging and encroachment but is now managed for ecosystem restoration. We used two survey methods: an established point count method for gibbons with some modifications, and straight line transects using auditory detections. Surveys were conducted in the three main forest types prevalent at the site: high, medium, and low canopy cover secondary forests. Mean group density estimates were higher from point counts than from line transects, and tended to be higher in less degraded forests within the study site. We consider points more time efficient and reliable than transects since detectability of gibbons was higher from points per unit effort. We recommend the additional use of Distance sampling methods to account for imperfect detection and provide other recommendations to improve surveys of gibbons. We estimate that the site holds at least 6,070 and as many as 11,360 gibbons. Our results demonstrate that degraded forests can be extremely important for the conservation of agile gibbons and that efforts to protect and restore such sites could contribute significantly to the conservation of the species. © 2014 Wiley Periodicals, Inc.

Keyhole imaging method for dynamic objects behind the occlusion area

NASA Astrophysics Data System (ADS)

Hao, Conghui; Chen, Xi; Dong, Liquan; Zhao, Yuejin; Liu, Ming; Kong, Lingqin; Hui, Mei; Liu, Xiaohua; Wu, Hong

2018-01-01

A method of keyhole imaging based on camera array is realized to obtain the video image behind a keyhole in shielded space at a relatively long distance. We get the multi-angle video images by using a 2×2 CCD camera array to take the images behind the keyhole in four directions. The multi-angle video images are saved in the form of frame sequences. This paper presents a method of video frame alignment. In order to remove the non-target area outside the aperture, we use the canny operator and morphological method to realize the edge detection of images and fill the images. The image stitching of four images is accomplished on the basis of the image stitching algorithm of two images. In the image stitching algorithm of two images, the SIFT method is adopted to accomplish the initial matching of images, and then the RANSAC algorithm is applied to eliminate the wrong matching points and to obtain a homography matrix. A method of optimizing transformation matrix is proposed in this paper. Finally, the video image with larger field of view behind the keyhole can be synthesized with image frame sequence in which every single frame is stitched. The results show that the screen of the video is clear and natural, the brightness transition is smooth. There is no obvious artificial stitching marks in the video, and it can be applied in different engineering environment .

Dynamic frame resizing with convolutional neural network for efficient video compression

NASA Astrophysics Data System (ADS)

Kim, Jaehwan; Park, Youngo; Choi, Kwang Pyo; Lee, JongSeok; Jeon, Sunyoung; Park, JeongHoon

2017-09-01

In the past, video codecs such as vc-1 and H.263 used a technique to encode reduced-resolution video and restore original resolution from the decoder for improvement of coding efficiency. The techniques of vc-1 and H.263 Annex Q are called dynamic frame resizing and reduced-resolution update mode, respectively. However, these techniques have not been widely used due to limited performance improvements that operate well only under specific conditions. In this paper, video frame resizing (reduced/restore) technique based on machine learning is proposed for improvement of coding efficiency. The proposed method features video of low resolution made by convolutional neural network (CNN) in encoder and reconstruction of original resolution using CNN in decoder. The proposed method shows improved subjective performance over all the high resolution videos which are dominantly consumed recently. In order to assess subjective quality of the proposed method, Video Multi-method Assessment Fusion (VMAF) which showed high reliability among many subjective measurement tools was used as subjective metric. Moreover, to assess general performance, diverse bitrates are tested. Experimental results showed that BD-rate based on VMAF was improved by about 51% compare to conventional HEVC. Especially, VMAF values were significantly improved in low bitrate. Also, when the method is subjectively tested, it had better subjective visual quality in similar bit rate.

COMPARISON OF USEPA FIELD SAMPLING METHODS FOR BENTHIC MACROINVERTEBRATE STUDIES

EPA Science Inventory

Two U.S. Environmental Protection Agency (USEPA) macroinvertebrate sampling protocols were compared in the Mid-Atlantic Highlands region. The Environmental Monitoring and Assessment Program (EMAP) wadeable streams protocol results in a single composite sample from nine transects...

Content Based Lecture Video Retrieval Using Speech and Video Text Information

ERIC Educational Resources Information Center

Yang, Haojin; Meinel, Christoph

2014-01-01

In the last decade e-lecturing has become more and more popular. The amount of lecture video data on the "World Wide Web" (WWW) is growing rapidly. Therefore, a more efficient method for video retrieval in WWW or within large lecture video archives is urgently needed. This paper presents an approach for automated video indexing and video…

Self-Supervised Video Hashing With Hierarchical Binary Auto-Encoder.

PubMed

Song, Jingkuan; Zhang, Hanwang; Li, Xiangpeng; Gao, Lianli; Wang, Meng; Hong, Richang

2018-07-01

Existing video hash functions are built on three isolated stages: frame pooling, relaxed learning, and binarization, which have not adequately explored the temporal order of video frames in a joint binary optimization model, resulting in severe information loss. In this paper, we propose a novel unsupervised video hashing framework dubbed self-supervised video hashing (SSVH), which is able to capture the temporal nature of videos in an end-to-end learning to hash fashion. We specifically address two central problems: 1) how to design an encoder-decoder architecture to generate binary codes for videos and 2) how to equip the binary codes with the ability of accurate video retrieval. We design a hierarchical binary auto-encoder to model the temporal dependencies in videos with multiple granularities, and embed the videos into binary codes with less computations than the stacked architecture. Then, we encourage the binary codes to simultaneously reconstruct the visual content and neighborhood structure of the videos. Experiments on two real-world data sets show that our SSVH method can significantly outperform the state-of-the-art methods and achieve the current best performance on the task of unsupervised video retrieval.

Self-Supervised Video Hashing With Hierarchical Binary Auto-Encoder

NASA Astrophysics Data System (ADS)

Song, Jingkuan; Zhang, Hanwang; Li, Xiangpeng; Gao, Lianli; Wang, Meng; Hong, Richang

2018-07-01

Existing video hash functions are built on three isolated stages: frame pooling, relaxed learning, and binarization, which have not adequately explored the temporal order of video frames in a joint binary optimization model, resulting in severe information loss. In this paper, we propose a novel unsupervised video hashing framework dubbed Self-Supervised Video Hashing (SSVH), that is able to capture the temporal nature of videos in an end-to-end learning-to-hash fashion. We specifically address two central problems: 1) how to design an encoder-decoder architecture to generate binary codes for videos; and 2) how to equip the binary codes with the ability of accurate video retrieval. We design a hierarchical binary autoencoder to model the temporal dependencies in videos with multiple granularities, and embed the videos into binary codes with less computations than the stacked architecture. Then, we encourage the binary codes to simultaneously reconstruct the visual content and neighborhood structure of the videos. Experiments on two real-world datasets (FCVID and YFCC) show that our SSVH method can significantly outperform the state-of-the-art methods and achieve the currently best performance on the task of unsupervised video retrieval.

A systematic review of methods for studying consumer health YouTube videos, with implications for systematic reviews.

PubMed

Sampson, Margaret; Cumber, Jordi; Li, Claudia; Pound, Catherine M; Fuller, Ann; Harrison, Denise

2013-01-01

Background. YouTube is an increasingly important medium for consumer health information - with content provided by healthcare professionals, government and non-government organizations, industry, and consumers themselves. It is a rapidly developing area of study for healthcare researchers. We examine the methods used in reviews of YouTube consumer health videos to identify trends and best practices. Methods and Materials. Published reviews of consumer-oriented health-related YouTube videos were identified through PubMed. Data extracted from these studies included type of journal, topic, characteristics of the search, methods of review including number of reviewers and method to achieve consensus between reviewers, inclusion and exclusion criteria, characteristics of the videos reported, ethical oversight, and follow-up. Results. Thirty-three studies were identified. Most were recent and published in specialty journals. Typically, these included more than 100 videos, and were examined by multiple reviewers. Most studies described characteristics of the videos, number of views, and sometime characteristics of the viewers. Accuracy of portrayal of the health issue under consideration was a common focus. Conclusion. Optimal transparency and reproducibility of studies of YouTube health-related videos can be achieved by following guidance designed for systematic review reporting, with attention to several elements specific to the video medium. Particularly when seeking to replicate consumer viewing behavior, investigators should consider the method used to select search terms, and use a snowballing rather than a sequential screening approach. Discontinuation protocols for online screening of relevance ranked search results is an area identified for further development.

A systematic review of methods for studying consumer health YouTube videos, with implications for systematic reviews

PubMed Central

Cumber, Jordi; Li, Claudia; Pound, Catherine M.; Fuller, Ann; Harrison, Denise

2013-01-01

Background. YouTube is an increasingly important medium for consumer health information – with content provided by healthcare professionals, government and non-government organizations, industry, and consumers themselves. It is a rapidly developing area of study for healthcare researchers. We examine the methods used in reviews of YouTube consumer health videos to identify trends and best practices. Methods and Materials. Published reviews of consumer-oriented health-related YouTube videos were identified through PubMed. Data extracted from these studies included type of journal, topic, characteristics of the search, methods of review including number of reviewers and method to achieve consensus between reviewers, inclusion and exclusion criteria, characteristics of the videos reported, ethical oversight, and follow-up. Results. Thirty-three studies were identified. Most were recent and published in specialty journals. Typically, these included more than 100 videos, and were examined by multiple reviewers. Most studies described characteristics of the videos, number of views, and sometime characteristics of the viewers. Accuracy of portrayal of the health issue under consideration was a common focus. Conclusion. Optimal transparency and reproducibility of studies of YouTube health-related videos can be achieved by following guidance designed for systematic review reporting, with attention to several elements specific to the video medium. Particularly when seeking to replicate consumer viewing behavior, investigators should consider the method used to select search terms, and use a snowballing rather than a sequential screening approach. Discontinuation protocols for online screening of relevance ranked search results is an area identified for further development. PMID:24058879

Streamed video clips to reduce anxiety in children during inhaled induction of anesthesia.

PubMed

Mifflin, Katherine A; Hackmann, Thomas; Chorney, Jill Maclaren

2012-11-01

Anesthesia induction in children is frequently achieved by inhalation of nitrous oxide and sevoflurane. Pediatric anesthesiologists commonly use distraction techniques such as humor or nonprocedural talk to reduce anxiety and facilitate a smooth transition at this critical phase. There is a large body of successful distraction research that explores the use of video and television distraction methods for minor medical and dental procedures, but little research on the use of this method for ambulatory surgery. In this randomized control trial study we examined whether video distraction is effective in reducing the anxiety of children undergoing inhaled induction before ambulatory surgery. Children (control = 47, video = 42) between 2 and 10 years old undergoing ambulatory surgery were randomly assigned to a video distraction or control group. In the video distraction group a video clip of the child's preference was played during induction, and the control group received traditional distraction methods during induction. The modified Yale Preoperative Anxiety Scale was used to assess the children's anxiety before and during the process of receiving inhalation anesthetics. All subjects were similar in their age and anxiety scores before entering the operating rooms. Children in the video distraction group were significantly less anxious at induction and showed a significantly smaller change in anxiety from holding to induction than did children in the control group. Playing video clips during the inhaled induction of children undergoing ambulatory surgery is an effective method of reducing anxiety. Therefore, pediatric anesthesiologists may consider using video distraction as a useful, valid, alternative strategy for achieving a smooth transition to the anesthetized state.

An improved multi-paths optimization method for video stabilization

NASA Astrophysics Data System (ADS)

Qin, Tao; Zhong, Sheng

2018-03-01

For video stabilization, the difference between original camera motion path and the optimized one is proportional to the cropping ratio and warping ratio. A good optimized path should preserve the moving tendency of the original one meanwhile the cropping ratio and warping ratio of each frame should be kept in a proper range. In this paper we use an improved warping-based motion representation model, and propose a gauss-based multi-paths optimization method to get a smoothing path and obtain a stabilized video. The proposed video stabilization method consists of two parts: camera motion path estimation and path smoothing. We estimate the perspective transform of adjacent frames according to warping-based motion representation model. It works well on some challenging videos where most previous 2D methods or 3D methods fail for lacking of long features trajectories. The multi-paths optimization method can deal well with parallax, as we calculate the space-time correlation of the adjacent grid, and then a kernel of gauss is used to weigh the motion of adjacent grid. Then the multi-paths are smoothed while minimize the crop ratio and the distortion. We test our method on a large variety of consumer videos, which have casual jitter and parallax, and achieve good results.

Hypervideo.

ERIC Educational Resources Information Center

Locatis, Craig; And Others

1990-01-01

Discusses methods for incorporating video into hypermedia programs. Knowledge representation in hypermedia is explained; video production techniques are discussed; comparisons between linear video, interactive video, and hypervideo are presented; appropriate conditions for hypervideo use are examined; and a need for new media research is…

Shot boundary detection and label propagation for spatio-temporal video segmentation

NASA Astrophysics Data System (ADS)

Piramanayagam, Sankaranaryanan; Saber, Eli; Cahill, Nathan D.; Messinger, David

2015-02-01

This paper proposes a two stage algorithm for streaming video segmentation. In the first stage, shot boundaries are detected within a window of frames by comparing dissimilarity between 2-D segmentations of each frame. In the second stage, the 2-D segments are propagated across the window of frames in both spatial and temporal direction. The window is moved across the video to find all shot transitions and obtain spatio-temporal segments simultaneously. As opposed to techniques that operate on entire video, the proposed approach consumes significantly less memory and enables segmentation of lengthy videos. We tested our segmentation based shot detection method on the TRECVID 2007 video dataset and compared it with block-based technique. Cut detection results on the TRECVID 2007 dataset indicate that our algorithm has comparable results to the best of the block-based methods. The streaming video segmentation routine also achieves promising results on a challenging video segmentation benchmark database.

Gradual cut detection using low-level vision for digital video

NASA Astrophysics Data System (ADS)

Lee, Jae-Hyun; Choi, Yeun-Sung; Jang, Ok-bae

1996-09-01

Digital video computing and organization is one of the important issues in multimedia system, signal compression, or database. Video should be segmented into shots to be used for identification and indexing. This approach requires a suitable method to automatically locate cut points in order to separate shot in a video. Automatic cut detection to isolate shots in a video has received considerable attention due to many practical applications; our video database, browsing, authoring system, retrieval and movie. Previous studies are based on a set of difference mechanisms and they measured the content changes between video frames. But they could not detect more special effects which include dissolve, wipe, fade-in, fade-out, and structured flashing. In this paper, a new cut detection method for gradual transition based on computer vision techniques is proposed. And then, experimental results applied to commercial video are presented and evaluated.

A new metric to assess temporal coherence for video retargeting

NASA Astrophysics Data System (ADS)

Li, Ke; Yan, Bo; Yuan, Binhang

2014-10-01

In video retargeting, how to assess the performance in maintaining temporal coherence has become the prominent challenge. In this paper, we will present a new objective measurement to assess temporal coherence after video retargeting. It's a general metric to assess jittery artifact for both discrete and continuous video retargeting methods, the accuracy of which is verified by psycho-visual tests. As a result, our proposed assessment method possesses huge practical significance.

Method and apparatus for reading meters from a video image

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

Lewis, T.J.; Ferguson, J.J.

1995-12-31

A method and system enable acquisition of data about an environment from one or more meters using video images. One or more meters are imaged by a video camera and the video signal is digitized. Then, each region of the digital image which corresponds to the indicator of the meter is calibrated and the video signal is analyzed to determine the value indicated by each meter indicator. Finally, from the value indicated by each meter indicator in the calibrated region, a meter reading is generated. The method and system offer the advantages of automatic data collection in a relatively non-intrusivemore » manner without making any complicated or expensive electronic connections, and without requiring intensive manpower.« less

Method and apparatus for reading meters from a video image

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

Lewis, T.J.; Ferguson, J.J.

1997-09-30

A method and system to enable acquisition of data about an environment from one or more meters using video images. One or more meters are imaged by a video camera and the video signal is digitized. Then, each region of the digital image which corresponds to the indicator of the meter is calibrated and the video signal is analyzed to determine the value indicated by each meter indicator. Finally, from the value indicated by each meter indicator in the calibrated region, a meter reading is generated. The method and system offer the advantages of automatic data collection in a relativelymore » non-intrusive manner without making any complicated or expensive electronic connections, and without requiring intensive manpower. 1 fig.« less

Automated Production of Movies on a Cluster of Computers

NASA Technical Reports Server (NTRS)

Nail, Jasper; Le, Duong; Nail, William L.; Nail, William

2008-01-01

A method of accelerating and facilitating production of video and film motion-picture products, and software and generic designs of computer hardware to implement the method, are undergoing development. The method provides for automation of most of the tedious and repetitive tasks involved in editing and otherwise processing raw digitized imagery into final motion-picture products. The method was conceived to satisfy requirements, in industrial and scientific testing, for rapid processing of multiple streams of simultaneously captured raw video imagery into documentation in the form of edited video imagery and video derived data products for technical review and analysis. In the production of such video technical documentation, unlike in production of motion-picture products for entertainment, (1) it is often necessary to produce multiple video derived data products, (2) there are usually no second chances to repeat acquisition of raw imagery, (3) it is often desired to produce final products within minutes rather than hours, days, or months, and (4) consistency and quality, rather than aesthetics, are the primary criteria for judging the products. In the present method, the workflow has both serial and parallel aspects: processing can begin before all the raw imagery has been acquired, each video stream can be subjected to different stages of processing simultaneously on different computers that may be grouped into one or more cluster(s), and the final product may consist of multiple video streams. Results of processing on different computers are shared, so that workers can collaborate effectively.

Quantitative Characterization of Spurious Gibbs Waves in 45 CMIP5 Models

NASA Astrophysics Data System (ADS)

Geil, K. L.; Zeng, X.

2014-12-01

Gibbs oscillations appear in global climate models when representing fields, such as orography, that contain discontinuities or sharp gradients. It has been known for decades that the oscillations are associated with the transformation of the truncated spectral representation of a field to physical space and that the oscillations can also be present in global models that do not use spectral methods. The spurious oscillations are potentially detrimental to model simulations (e.g., over ocean) and this work provides a quantitative characterization of the Gibbs oscillations that appear across the Coupled Model Intercomparison Project Phase 5 (CMIP5) models. An ocean transect running through the South Pacific High toward the Andes is used to characterize the oscillations in ten different variables. These oscillations are found to be stationary and hence are not caused by (physical) waves in the atmosphere. We quantify the oscillation amplitude using the root mean square difference (RMSD) between the transect of a variable and its running mean (rather than the constant mean across the transect). We also compute the RMSD to interannual variability (IAV) ratio, which provides a relative measure of the oscillation amplitude. Of the variables examined, the largest RMSD values exist in the surface pressure field of spectral models, while the smallest RMSD values within the surface pressure field come from models that use finite difference (FD) techniques. Many spectral models have a surface pressure RMSD that is 2 to 15 times greater than IAV over the transect and an RMSD:IAV ratio greater than one for many other variables including surface temperature, incoming shortwave radiation at the surface, incoming longwave radiation at the surface, and total cloud fraction. In general, the FD models out-perform the spectral models, but not all the spectral models have large amplitude oscillations and there are a few FD models where the oscillations do appear. Finally, we present a brief comparison of the numerical methods of a select few models to better understand their Gibbs oscillations.

Rapid estimation of recharge potential in ephemeral-stream channels using electromagnetic methods, and measurements of channel and vegetation characteristics

USGS Publications Warehouse

Callegary, J.B.; Leenhouts, J.M.; Paretti, N.V.; Jones, Christopher A.

2007-01-01

To classify recharge potential (RCP) in ephemeral-stream channels, a method was developed that incorporates information about channel geometry, vegetation characteristics, and bed-sediment apparent electrical conductivity (??a). Recharge potential is not independently measurable, but is instead formulated as a site-specific, qualitative parameter. We used data from 259 transects across two ephemeral-stream channels near Sierra Vista, Arizona, a location with a semiarid climate. Seven data types were collected: ??a averaged over two depth intervals (0-3 m, and 0-6 m), channel incision depth and width, diameter-at-breast-height of the largest tree, woody-plant and grass density. A two-tiered system was used to classify a transect's RCP. In the first tier, transects were categorized by estimates of near-surface-sediment hydraulic permeability as low, moderate, or high using measurements of 0-3 m-depth ??a. Each of these categories was subdivided into low, medium, or high RCP classes using the remaining six data types, thus yielding a total of nine RCP designations. Six sites in the study area were used to compare RCP and ??a with previously measured surrogates for hydraulic permeability. Borehole-averaged percent fines showed a moderate correlation with both shallow and deep ??a measurements, however, correlation of point measurements of saturated hydraulic conductivity, percent fines, and cylinder infiltrometer measurements with ??a and RCP was generally poor. The poor correlation was probably caused by the relatively large measurement volume and spatial averaging of ??a compared with the spatially-limited point measurements. Because of the comparatively large spatial extent of measurement transects and variety of data types collected, RCP estimates can give a more complete picture of the major factors affecting recharge at a site than is possible through point or borehole-averaged estimates of hydraulic permeability alone. ?? 2007 Elsevier B.V. All rights reserved.

Transected sciatic nerve repair by diode laser protein soldering.

PubMed

Fekrazad, Reza; Mortezai, Omid; Pedram, MirSepehr; Kalhori, Katayoun Am; Joharchi, Khojasteh; Mansoori, Korosh; Ebrahimi, Roja; Mashhadiabbas, Fatemeh

2017-08-01

Despite advances in microsurgical techniques, repair of peripheral nerve injuries (PNI) is still a major challenge in regenerative medicine. The standard treatment for PNI includes suturing and anasthomosis of the transected nerve. The objective of this study was to compare neurorraphy (nerve repair) using standard suturingto diode laser protein soldering on the functional recovery of transected sciatic nerves. Thirty adult male Fischer-344 Wistar rats were randomly assigned to 3 groups: 1. The control group, no repair, 2. the standard of care suture group, and 3. The laser/protein solder group. For all three groups, the sciatic nerve was transected and the repair was done immediately. For the suture repair group, 10.0 prolene suture was used and for the laser/protein solder group a diode laser (500mW output power) in combination with bovine serum albumen and indocyanine green dye was used. Behavioral assessment by sciatic functional index was done on all rats biweekly. At 12weeks post-surgery, EMG recordings were done on all the rats and the rats were euthanized for histological evaluation of the sciatic nerves. The one-way ANOVA test was used for statistical analysis. The average time required to perform the surgery was significantly shorter for the laser-assisted nerve repair group compared to the suture group. The EMG evaluation revealed no difference between the two groups. Based on the sciatic function index the laser group was significantly better than the suture group after 12weeks (p<0.05). Histopathologic evaluation indicated that the epineurium recovery was better in the laser group (p<0.05). There was no difference in the inflammation between the suture and laser groups. Based on this evidence, laser/protein nerve soldering is a more efficient and efficacious method for repair of nerve injury compared to neurorraphy using standard suturing methods. Copyright © 2017 Elsevier B.V. All rights reserved.

Interactive Video Usage on Autism Spectrum Disorder Training in Medical Education

ERIC Educational Resources Information Center

Taslibeyaz, Elif; Dursun, Onur Burak; Karaman, Selcuk

2017-01-01

This study aimed to compare the effects of interactive and non-interactive videos concerning the autism spectrum disorder on medical students' achievement. It also evaluated the relation between the interactive videos' interactivity and the students' decision-making process. It used multiple methods, including quantitative and qualitative methods.…

Does Video-Autotutorial Instruction Improve College Student Achievement?

ERIC Educational Resources Information Center

Fisher, K. M.; And Others

1977-01-01

Compares student achievement in an upper-division college introductory course taught by the video-autotutorial method with that in two comparable courses taught by the lecture-discussion method. Pre-post tests of 623 students reveal that video-autotutorial students outperform lecture/discussion participants at all ability levels and that in…

A novel video recommendation system based on efficient retrieval of human actions

NASA Astrophysics Data System (ADS)

Ramezani, Mohsen; Yaghmaee, Farzin

2016-09-01

In recent years, fast growth of online video sharing eventuated new issues such as helping users to find their requirements in an efficient way. Hence, Recommender Systems (RSs) are used to find the users' most favorite items. Finding these items relies on items or users similarities. Though, many factors like sparsity and cold start user impress the recommendation quality. In some systems, attached tags are used for searching items (e.g. videos) as personalized recommendation. Different views, incomplete and inaccurate tags etc. can weaken the performance of these systems. Considering the advancement of computer vision techniques can help improving RSs. To this end, content based search can be used for finding items (here, videos are considered). In such systems, a video is taken from the user to find and recommend a list of most similar videos to the query one. Due to relating most videos to humans, we present a novel low complex scalable method to recommend videos based on the model of included action. This method has recourse to human action retrieval approaches. For modeling human actions, some interest points are extracted from each action and their motion information are used to compute the action representation. Moreover, a fuzzy dissimilarity measure is presented to compare videos for ranking them. The experimental results on HMDB, UCFYT, UCF sport and KTH datasets illustrated that, in most cases, the proposed method can reach better results than most used methods.

Heterogeneity image patch index and its application to consumer video summarization.

PubMed

Dang, Chinh T; Radha, Hayder

2014-06-01

Automatic video summarization is indispensable for fast browsing and efficient management of large video libraries. In this paper, we introduce an image feature that we refer to as heterogeneity image patch (HIP) index. The proposed HIP index provides a new entropy-based measure of the heterogeneity of patches within any picture. By evaluating this index for every frame in a video sequence, we generate a HIP curve for that sequence. We exploit the HIP curve in solving two categories of video summarization applications: key frame extraction and dynamic video skimming. Under the key frame extraction frame-work, a set of candidate key frames is selected from abundant video frames based on the HIP curve. Then, a proposed patch-based image dissimilarity measure is used to create affinity matrix of these candidates. Finally, a set of key frames is extracted from the affinity matrix using a min–max based algorithm. Under video skimming, we propose a method to measure the distance between a video and its skimmed representation. The video skimming problem is then mapped into an optimization framework and solved by minimizing a HIP-based distance for a set of extracted excerpts. The HIP framework is pixel-based and does not require semantic information or complex camera motion estimation. Our simulation results are based on experiments performed on consumer videos and are compared with state-of-the-art methods. It is shown that the HIP approach outperforms other leading methods, while maintaining low complexity.

Semantic Shot Classification in Sports Video

NASA Astrophysics Data System (ADS)

Duan, Ling-Yu; Xu, Min; Tian, Qi

2003-01-01

In this paper, we present a unified framework for semantic shot classification in sports videos. Unlike previous approaches, which focus on clustering by aggregating shots with similar low-level features, the proposed scheme makes use of domain knowledge of a specific sport to perform a top-down video shot classification, including identification of video shot classes for each sport, and supervised learning and classification of the given sports video with low-level and middle-level features extracted from the sports video. It is observed that for each sport we can predefine a small number of semantic shot classes, about 5~10, which covers 90~95% of sports broadcasting video. With the supervised learning method, we can map the low-level features to middle-level semantic video shot attributes such as dominant object motion (a player), camera motion patterns, and court shape, etc. On the basis of the appropriate fusion of those middle-level shot classes, we classify video shots into the predefined video shot classes, each of which has a clear semantic meaning. The proposed method has been tested over 4 types of sports videos: tennis, basketball, volleyball and soccer. Good classification accuracy of 85~95% has been achieved. With correctly classified sports video shots, further structural and temporal analysis, such as event detection, video skimming, table of content, etc, will be greatly facilitated.

Is video gaming, or video game addiction, associated with depression, academic achievement, heavy episodic drinking, or conduct problems?

PubMed Central

Brunborg, Geir Scott; Mentzoni, Rune Aune; Frøyland, Lars Roar

2014-01-01

Background and aims: While the relationships between video game use and negative consequences are debated, the relationships between video game addiction and negative consequences are fairly well established. However, previous studies suffer from methodological weaknesses that may have caused biased results. There is need for further investigation that benefits from the use of methods that avoid omitted variable bias. Methods: Two wave panel data was used from two surveys of 1,928 Norwegian adolescents aged 13 to 17 years. The surveys included measures of video game use, video game addiction, depression, heavy episodic drinking, academic achievement, and conduct problems. The data was analyzed using first-differencing, a regression method that is unbiased by time invariant individual factors. Results: Video game addiction was related to depression, lower academic achievement, and conduct problems, but time spent on video games was not related to any of the studied negative outcomes. Discussion: The findings were in line with a growing number of studies that have failed to find relationships between time spent on video games and negative outcomes. The current study is also consistent with previous studies in that video game addiction was related to other negative outcomes, but it made the added contribution that the relationships are unbiased by time invariant individual effects. However, future research should aim at establishing the temporal order of the supposed causal effects. Conclusions: Spending time playing video games does not involve negative consequences, but adolescents who experience problems related to video games are likely to also experience problems in other facets of life. PMID:25215212

Design unbiased estimation in line intersect sampling using segmented transects

Treesearch

David L.R. Affleck; Timothy G. Gregoire; Harry T. Valentine; Harry T. Valentine

2005-01-01

In many applications of line intersect sampling. transects consist of multiple, connected segments in a prescribed configuration. The relationship between the transect configuration and the selection probability of a population element is illustrated and a consistent sampling protocol, applicable to populations composed of arbitrarily shaped elements, is proposed. It...

Use of paper for treatment of a peripheral nerve trauma in the rat.

PubMed

Kauppila, T; Jyväsjärvi, E; Murtomäki, S; Mansikka, H; Pertovaara, A; Virtanen, I; Liesi, P

1997-09-29

Reinnervation of the muscles and skin in the rat hindpaw was studied after transection and attempted repair of the sciatic nerve. Reconnecting the transected nerve with lens cleaning paper was at least as effective in rejoining the transected nerves as traditional microsurgical neurorraphy. Paper induced a slightly bigger fibrous scar around the site of transection than neurorraphy, but this scar did not cause impairment of functional recovery or excessive signs of neuropathic pain. We conclude that a paper graft can be used in restorative surgery of severed peripheral nerves.

Activity recognition using Video Event Segmentation with Text (VEST)

NASA Astrophysics Data System (ADS)

Holloway, Hillary; Jones, Eric K.; Kaluzniacki, Andrew; Blasch, Erik; Tierno, Jorge

2014-06-01

Multi-Intelligence (multi-INT) data includes video, text, and signals that require analysis by operators. Analysis methods include information fusion approaches such as filtering, correlation, and association. In this paper, we discuss the Video Event Segmentation with Text (VEST) method, which provides event boundaries of an activity to compile related message and video clips for future interest. VEST infers meaningful activities by clustering multiple streams of time-sequenced multi-INT intelligence data and derived fusion products. We discuss exemplar results that segment raw full-motion video (FMV) data by using extracted commentary message timestamps, FMV metadata, and user-defined queries.

An objective method for a video quality evaluation in a 3DTV service

NASA Astrophysics Data System (ADS)

Wilczewski, Grzegorz

2015-09-01

The following article describes proposed objective method for a 3DTV video quality evaluation, a Compressed Average Image Intensity (CAII) method. Identification of the 3DTV service's content chain nodes enables to design a versatile, objective video quality metric. It is based on an advanced approach to the stereoscopic videostream analysis. Insights towards designed metric mechanisms, as well as the evaluation of performance of the designed video quality metric, in the face of the simulated environmental conditions are herein discussed. As a result, created CAII metric might be effectively used in a variety of service quality assessment applications.

Segment scheduling method for reducing 360° video streaming latency

NASA Astrophysics Data System (ADS)

Gudumasu, Srinivas; Asbun, Eduardo; He, Yong; Ye, Yan

2017-09-01

360° video is an emerging new format in the media industry enabled by the growing availability of virtual reality devices. It provides the viewer a new sense of presence and immersion. Compared to conventional rectilinear video (2D or 3D), 360° video poses a new and difficult set of engineering challenges on video processing and delivery. Enabling comfortable and immersive user experience requires very high video quality and very low latency, while the large video file size poses a challenge to delivering 360° video in a quality manner at scale. Conventionally, 360° video represented in equirectangular or other projection formats can be encoded as a single standards-compliant bitstream using existing video codecs such as H.264/AVC or H.265/HEVC. Such method usually needs very high bandwidth to provide an immersive user experience. While at the client side, much of such high bandwidth and the computational power used to decode the video are wasted because the user only watches a small portion (i.e., viewport) of the entire picture. Viewport dependent 360°video processing and delivery approaches spend more bandwidth on the viewport than on non-viewports and are therefore able to reduce the overall transmission bandwidth. This paper proposes a dual buffer segment scheduling algorithm for viewport adaptive streaming methods to reduce latency when switching between high quality viewports in 360° video streaming. The approach decouples the scheduling of viewport segments and non-viewport segments to ensure the viewport segment requested matches the latest user head orientation. A base layer buffer stores all lower quality segments, and a viewport buffer stores high quality viewport segments corresponding to the most recent viewer's head orientation. The scheduling scheme determines viewport requesting time based on the buffer status and the head orientation. This paper also discusses how to deploy the proposed scheduling design for various viewport adaptive video streaming methods. The proposed dual buffer segment scheduling method is implemented in an end-to-end tile based 360° viewports adaptive video streaming platform, where the entire 360° video is divided into a number of tiles, and each tile is independently encoded into multiple quality level representations. The client requests different quality level representations of each tile based on the viewer's head orientation and the available bandwidth, and then composes all tiles together for rendering. The simulation results verify that the proposed dual buffer segment scheduling algorithm reduces the viewport switch latency, and utilizes available bandwidth more efficiently. As a result, a more consistent immersive 360° video viewing experience can be presented to the user.

The Distribution and Magnitude of Glacial Erosion on 103-year Timescales at Engabreen, Norway

NASA Astrophysics Data System (ADS)

Rand, C.; Goehring, B. M.

2017-12-01

We derive the magnitudes of glacial erosion integrated over 103-year timescales across a transect transverse to the direction of ice flow at Engabreen, Norway. Understanding the distribution of glacial erosion is important for several reasons, including sediment budgeting to fjord environments, development of robust landscape evolution models, and if a better understanding between erosion and ice-bed interface properties (e.g., sliding rate, basal water pressure) can be developed, we can use records of glacial erosion to infer glaciological properties that can ultimately benefit models of past and future glaciers. With few exceptions, measurements of glacial erosion are limited to the historical past and even then are rare owing to the difficulty of accessing the glacier bed. One method proven useful in estimating glacial erosion on 103-year timescales is to measure the remaining concentrations of cosmogenic nuclides that accumulate in exposed bedrock during periods of retracted glacier extent and are removed by glacial erosion and radioactive decay during ice cover. Here we will present measurements of 14C and 10Be measured in proglacial bedrock from Engabreen. Our transects are ca. 600 and 400 meters in front of the modern ice front, and based on historical imagery, was ice covered until the recent past. Initial 10Be results show an increase in concentrations of nearly an order of magnitude from the samples near the center of the glacial trough to those on the lateral margin, consistent with conceptual models of glacial erosion parameterized in terms of sliding velocity. Naïve exposure ages that assume no subglacial erosion range from 0.22 - 9.04 ka. More importantly, we can estimate erosion depths by assuming zero erosion of the highest concentration sample along the two transects and calculate the amount of material removed to yield the lower concentrations elsewhere along the two transects. Results indicate minimum erosion depths of 1-183 cm for most ice proximal transect and 7-56 cm for the more distal one.

Video image stabilization and registration--plus

NASA Technical Reports Server (NTRS)

Hathaway, David H. (Inventor)

2009-01-01

A method of stabilizing a video image displayed in multiple video fields of a video sequence includes the steps of: subdividing a selected area of a first video field into nested pixel blocks; determining horizontal and vertical translation of each of the pixel blocks in each of the pixel block subdivision levels from the first video field to a second video field; and determining translation of the image from the first video field to the second video field by determining a change in magnification of the image from the first video field to the second video field in each of horizontal and vertical directions, and determining shear of the image from the first video field to the second video field in each of the horizontal and vertical directions.

Extraction and analysis of neuron firing signals from deep cortical video microscopy

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

Kerekes, Ryan A; Blundon, Jay

We introduce a method for extracting and analyzing neuronal activity time signals from video of the cortex of a live animal. The signals correspond to the firing activity of individual cortical neurons. Activity signals are based on the changing fluorescence of calcium indicators in the cells over time. We propose a cell segmentation method that relies on a user-specified center point, from which the signal extraction method proceeds. A stabilization approach is used to reduce tissue motion in the video. The extracted signal is then processed to flatten the baseline and detect action potentials. We show results from applying themore » method to a cortical video of a live mouse.« less

Normalized Temperature Contrast Processing in Flash Infrared Thermography

NASA Technical Reports Server (NTRS)

Koshti, Ajay M.

2016-01-01

The paper presents further development in normalized contrast processing of flash infrared thermography method by the author given in US 8,577,120 B1. The method of computing normalized image or pixel intensity contrast, and normalized temperature contrast are provided, including converting one from the other. Methods of assessing emissivity of the object, afterglow heat flux, reflection temperature change and temperature video imaging during flash thermography are provided. Temperature imaging and normalized temperature contrast imaging provide certain advantages over pixel intensity normalized contrast processing by reducing effect of reflected energy in images and measurements, providing better quantitative data. The subject matter for this paper mostly comes from US 9,066,028 B1 by the author. Examples of normalized image processing video images and normalized temperature processing video images are provided. Examples of surface temperature video images, surface temperature rise video images and simple contrast video images area also provided. Temperature video imaging in flash infrared thermography allows better comparison with flash thermography simulation using commercial software which provides temperature video as the output. Temperature imaging also allows easy comparison of surface temperature change to camera temperature sensitivity or noise equivalent temperature difference (NETD) to assess probability of detecting (POD) anomalies.

Method and system for efficient video compression with low-complexity encoder

NASA Technical Reports Server (NTRS)

Chen, Jun (Inventor); He, Dake (Inventor); Sheinin, Vadim (Inventor); Jagmohan, Ashish (Inventor); Lu, Ligang (Inventor)

2012-01-01

Disclosed are a method and system for video compression, wherein the video encoder has low computational complexity and high compression efficiency. The disclosed system comprises a video encoder and a video decoder, wherein the method for encoding includes the steps of converting a source frame into a space-frequency representation; estimating conditional statistics of at least one vector of space-frequency coefficients; estimating encoding rates based on the said conditional statistics; and applying Slepian-Wolf codes with the said computed encoding rates. The preferred method for decoding includes the steps of; generating a side-information vector of frequency coefficients based on previously decoded source data, encoder statistics, and previous reconstructions of the source frequency vector; and performing Slepian-Wolf decoding of at least one source frequency vector based on the generated side-information, the Slepian-Wolf code bits and the encoder statistics.

Restoration of motor function after operative reconstruction of the acutely transected spinal cord in the canine model.

PubMed

Liu, Zehan; Ren, Shuai; Fu, Kuang; Wu, Qiong; Wu, Jun; Hou, Liting; Pan, Hong; Sun, Linlin; Zhang, Jian; Wang, Bingjian; Miao, Qing; Sun, Guiyin; Bonicalzi, Vincenzo; Canavero, Sergio; Ren, Xiaoping

2018-05-01

Cephalosomatic anastomosis or what has been called a "head transplantation" requires full reconnection of the respective transected ends of the spinal cords. The GEMINI spinal cord fusion protocol has been developed for this reason. Here, we report the first randomized, controlled study of the GEMINI protocol in large animals. We conducted a randomized, controlled study of a complete transection of the spinal cord at the level of T10 in dogs at Harbin Medical University, Harbin, China. These dogs were followed for up to 8 weeks postoperatively by assessments of recovery of motor function, somato-sensory evoked potentials, and diffusion tensor imaging using magnetic resonance imaging. A total of 12 dogs were subjected to operative exposure of the dorsal aspect of the spinal cord after laminectomy and longitudinal durotomy followed by a very sharp, controlled, full-thickness, complete transection of the spinal cord at T10. The fusogen, polyethylene glycol, was applied topically to the site of the spinal cord transection in 7 of 12 dogs; 0.9% NaCl saline was applied to the site of transection in the remaining 5 control dogs. Dogs were selected randomly to receive polyethylene glycol or saline. All polyethylene glycol-treated dogs reacquired a substantial amount of motor function versus none in controls over these first 2 months as assessed on the 20-point (0-19), canine, Basso-Beattie-Bresnahan rating scale (P<.006). Somatosensory evoked potentials confirmed restoration of electrical conduction cranially across the site of spinal cord transection which improved over time. Diffusion tensor imaging, a magnetic resonance permutation that assesses the integrity of nerve fibers and cells, showed restitution of the transected spinal cord with polyethylene glycol treatment (at-injury level difference: P<.02). A sharply and fully transected spinal cord at the level of T10 can be reconstructed with restoration of many aspects of electrical continuity in large animals following the GEMINI spinal cord fusion protocol, with objective evidence of motor recovery and of electrical continuity across the site of transection, opening the way to the first cephalosomatic anastomosis. (Surgery 2017;160:XXX-XXX.). Copyright © 2017. Published by Elsevier Inc.

A novel visual saliency detection method for infrared video sequences

NASA Astrophysics Data System (ADS)

Wang, Xin; Zhang, Yuzhen; Ning, Chen

2017-12-01

Infrared video applications such as target detection and recognition, moving target tracking, and so forth can benefit a lot from visual saliency detection, which is essentially a method to automatically localize the ;important; content in videos. In this paper, a novel visual saliency detection method for infrared video sequences is proposed. Specifically, for infrared video saliency detection, both the spatial saliency and temporal saliency are considered. For spatial saliency, we adopt a mutual consistency-guided spatial cues combination-based method to capture the regions with obvious luminance contrast and contour features. For temporal saliency, a multi-frame symmetric difference approach is proposed to discriminate salient moving regions of interest from background motions. Then, the spatial saliency and temporal saliency are combined to compute the spatiotemporal saliency using an adaptive fusion strategy. Besides, to highlight the spatiotemporal salient regions uniformly, a multi-scale fusion approach is embedded into the spatiotemporal saliency model. Finally, a Gestalt theory-inspired optimization algorithm is designed to further improve the reliability of the final saliency map. Experimental results demonstrate that our method outperforms many state-of-the-art saliency detection approaches for infrared videos under various backgrounds.

Ulinastatin attenuates neuropathic pain induced by L5-VRT via the calcineurin/IL-10 pathway.

PubMed

Ouyang, Handong; Nie, Bilin; Wang, Peizong; Li, Qiang; Huang, Wan; Xin, Wenjun; Zeng, Weian; Liu, Xianguo

2016-01-01

Previous studies have shown that ulinastatin, an effective inhibitor of the inflammatory response in clinical applications, can attenuate hyperalgesia in rodents. However, the underlying mechanism remains unclear. In the present study, we first examined the change in the calcineurin level, which plays an important role in regulating cytokine release in the nervous system, following lumbar 5 ventral root transection in the rat. Furthermore, we determined whether intraperitoneal (i.p.) injection of ulinastatin attenuated pain behavior via inhibition of the calcineurin-mediated inflammatory response induced by lumbar 5 ventral root transection. The results showed that the paw withdrawal threshold and paw withdrawal latency were significantly decreased following lumbar 5 ventral root transection compared to the sham group. Neuropathic pain induced by lumbar 5 ventral root transection significantly decreased the expression of calcineurin in the DRG, and calcineurin was mostly located with NF-200-positive cells, IB4-positive cells, and CGRP-positive cells and less with GFAP-positive satellite cells. Furthermore, intrathecal (i.t.) injection of exogenous calcineurin attenuated the pain behavior induced by lumbar 5 ventral root transection. Importantly, intraperitoneal injection of ulinastatin alleviated the pain behavior and calcineurin downregulation induced by lumbar 5 ventral root transection. Lastly, the cytokine IL-10 was significantly decreased following lumbar 5 ventral root transection, and application of calcineurin (intrathecal) or ulinastatin (intraperitoneal) inhibited the IL-10 downregulation induced by lumbar 5 ventral root transection. These results suggested that ulinastatin, by acting on the CN/IL-10 pathway, might be a novel and effective drug for the treatment of neuropathic pain. © The Author(s) 2016.

Ulinastatin attenuates neuropathic pain induced by L5-VRT via the calcineurin/IL-10 pathway

PubMed Central

Ouyang, Handong; Nie, Bilin; Wang, Peizong; Li, Qiang; Huang, Wan; Xin, Wenjun; Liu, Xianguo

2016-01-01

Previous studies have shown that ulinastatin, an effective inhibitor of the inflammatory response in clinical applications, can attenuate hyperalgesia in rodents. However, the underlying mechanism remains unclear. In the present study, we first examined the change in the calcineurin level, which plays an important role in regulating cytokine release in the nervous system, following lumbar 5 ventral root transection in the rat. Furthermore, we determined whether intraperitoneal (i.p.) injection of ulinastatin attenuated pain behavior via inhibition of the calcineurin-mediated inflammatory response induced by lumbar 5 ventral root transection. The results showed that the paw withdrawal threshold and paw withdrawal latency were significantly decreased following lumbar 5 ventral root transection compared to the sham group. Neuropathic pain induced by lumbar 5 ventral root transection significantly decreased the expression of calcineurin in the DRG, and calcineurin was mostly located with NF-200-positive cells, IB4-positive cells, and CGRP-positive cells and less with GFAP-positive satellite cells. Furthermore, intrathecal (i.t.) injection of exogenous calcineurin attenuated the pain behavior induced by lumbar 5 ventral root transection. Importantly, intraperitoneal injection of ulinastatin alleviated the pain behavior and calcineurin downregulation induced by lumbar 5 ventral root transection. Lastly, the cytokine IL-10 was significantly decreased following lumbar 5 ventral root transection, and application of calcineurin (intrathecal) or ulinastatin (intraperitoneal) inhibited the IL-10 downregulation induced by lumbar 5 ventral root transection. These results suggested that ulinastatin, by acting on the CN/IL-10 pathway, might be a novel and effective drug for the treatment of neuropathic pain. PMID:27175013

Motivational Engagement and Video Gaming: A Mixed Methods Study

ERIC Educational Resources Information Center

Hoffman, Bobby; Nadelson, Louis

2010-01-01

A mixed methods design was used to identify factors associated with motivational engagement in video gaming. Self-report instruments were administered to 189 video game players to assess goal orientations, affect, need for cognition, and perceptions of engagement and flow. Simultaneously, a sub-set of 25 participants were interviewed and results…

Scalable gastroscopic video summarization via similar-inhibition dictionary selection.

PubMed

Wang, Shuai; Cong, Yang; Cao, Jun; Yang, Yunsheng; Tang, Yandong; Zhao, Huaici; Yu, Haibin

2016-01-01

This paper aims at developing an automated gastroscopic video summarization algorithm to assist clinicians to more effectively go through the abnormal contents of the video. To select the most representative frames from the original video sequence, we formulate the problem of gastroscopic video summarization as a dictionary selection issue. Different from the traditional dictionary selection methods, which take into account only the number and reconstruction ability of selected key frames, our model introduces the similar-inhibition constraint to reinforce the diversity of selected key frames. We calculate the attention cost by merging both gaze and content change into a prior cue to help select the frames with more high-level semantic information. Moreover, we adopt an image quality evaluation process to eliminate the interference of the poor quality images and a segmentation process to reduce the computational complexity. For experiments, we build a new gastroscopic video dataset captured from 30 volunteers with more than 400k images and compare our method with the state-of-the-arts using the content consistency, index consistency and content-index consistency with the ground truth. Compared with all competitors, our method obtains the best results in 23 of 30 videos evaluated based on content consistency, 24 of 30 videos evaluated based on index consistency and all videos evaluated based on content-index consistency. For gastroscopic video summarization, we propose an automated annotation method via similar-inhibition dictionary selection. Our model can achieve better performance compared with other state-of-the-art models and supplies more suitable key frames for diagnosis. The developed algorithm can be automatically adapted to various real applications, such as the training of young clinicians, computer-aided diagnosis or medical report generation. Copyright © 2015 Elsevier B.V. All rights reserved.

High definition in minimally invasive surgery: a review of methods for recording, editing, and distributing video.

PubMed

Kelly, Christopher R; Hogle, Nancy J; Landman, Jaime; Fowler, Dennis L

2008-09-01

The use of high-definition cameras and monitors during minimally invasive procedures can provide the surgeon and operating team with more than twice the resolution of standard definition systems. Although this dramatic improvement in visualization offers numerous advantages, the adoption of high definition cameras in the operating room can be challenging because new recording equipment must be purchased, and several new technologies are required to edit and distribute video. The purpose of this review article is to provide an overview of the popular methods for recording, editing, and distributing high-definition video. This article discusses the essential technical concepts of high-definition video, reviews the different kinds of equipment and methods most often used for recording, and describes several options for video distribution.

Transect versus grid trapping arrangements for sampling small-mammal communities

Treesearch

Dean E. Pearson; Leonard F. Ruggiero

2003-01-01

We compared transect and grid trapping arrangements for assessing small-mammal community composition and relative abundance for 2 years in 2 forest cover types in west-central Montana, USA. Transect arrangements yielded more total captures, more individual captures, and more species than grid arrangements in both cover types in both years. Differences between...

Demonstration of Pelvic Anatomy by Modified Midline Transection that Maintains Intact Internal Pelvic Organs

ERIC Educational Resources Information Center

Steinke, Hanno; Saito, Toshiyuki; Herrmann, Gudrun; Miyaki, Takayoshi; Hammer, Niels; Sandrock, Mara; Itoh, Masahiro; Spanel-Borowski, Katharina

2010-01-01

Gross dissection for demonstrating anatomy of the human pelvis has traditionally involved one of two approaches, each with advantages and disadvantages. Classic hemisection in the median plane through the pelvic ring transects the visceral organs but maintains two symmetric pelvic halves. An alternative paramedial transection compromises one side…

Sediment loads and transport at constructed chutes along the Missouri River - Upper Hamburg Chute near Nebraska City, Nebraska, and Kansas Chute near Peru, Nebraska

USGS Publications Warehouse

Densmore, Brenda K.; Rus, David L.; Moser, Matthew T.; Hall, Brent M.; Andersen, Michael J.

2016-02-04

Comparisons of concentrations and loads from EWI samples collected from different transects within a study site resulted in few significant differences, but comparisons are limited by small sample sizes and large within-transect variability. When comparing the Missouri River upstream transect to the chute inlet transect, similar results were determined in 2012 as were determined in 2008—the chute inlet affected the amount of sediment entering the chute from the main channel. In addition, the Kansas chute is potentially affecting the sediment concentration within the Missouri River main channel, but small sample size and construction activities within the chute limit the ability to fully understand either the effect of the chute in 2012 or the effect of the chute on the main channel during a year without construction. Finally, some differences in SSC were detected between the Missouri River upstream transects and the chute downstream transects; however, the effect of the chutes on the Missouri River main-channel sediment transport was difficult to isolate because of construction activities and sampling variability.

Changes in the structural properties of peripheral nerves after transection.

PubMed

Toby, E B; Meyer, B M; Schwappach, J; Alvine, G

1996-11-01

Changes in peripheral nerve structural properties after transection were measured weekly for 5 weeks in the distal stump of the sciatic nerve in 50 Sprague-Dawley rats. Each week after transection, the distal stump of the transected nerve showed increased stiffness when compared to intact nerves. Linear elastic stiffness reached a maximum at weeks 1 and 2 after transection, when the transected nerves were 15% stiffer than the contralateral control sides. Toughness was also increased and reached a maximum at week 4 with a 50% difference between values for experimental and control sides. Overall failure load was between 21% and 27% greater, peaking at week 3. An increase in stiffness of the distal stump would result in increased tension at the suture line, as the nerve gap is overcome when performing a delayed neurorraphy. These data suggest, with respect to structural properties, that an end-to-end repair should be carried out at the time of injury; after only 1 week, significant stiffness in the distal segment of the nerve developed, which should result in an increase in tension at the repair site.

Comparing High Definition Live Interactive and Store-and-Forward Consultations to In-Person Examinations.

PubMed

Marchell, Richard; Locatis, Craig; Burges, Gene; Maisiak, Richard; Liu, Wei-Li; Ackerman, Michael

2017-03-01

There is little teledermatology research directly comparing remote methods, even less research with two in-person dermatologist agreement providing a baseline for comparing remote methods, and no research using high definition video as a live interactive method. To compare in-person consultations with store-and-forward and live interactive methods, the latter having two levels of image quality. A controlled study was conducted where patients were examined in-person, by high definition video, and by store-and-forward methods. The order patients experienced methods and residents assigned methods rotated, although an attending always saw patients in-person. The type of high definition video employed, lower resolution compressed or higher resolution uncompressed, was alternated between clinics. Primary and differential diagnoses, biopsy recommendations, and diagnostic and biopsy confidence ratings were recorded. Concordance and confidence were significantly better for in-person versus remote methods and biopsy recommendations were lower. Store-and-forward and higher resolution uncompressed video results were similar and better than those for lower resolution compressed video. Dermatology residents took store-and-forward photos and their quality was likely superior to those normally taken in practice. There were variations in expertise between the attending and second and third year residents. The superiority of in-person consultations suggests the tendencies to order more biopsies or still see patients in-person are often justified in teledermatology and that high resolution uncompressed video can close the resolution gap between store-and-forward and live interactive methods.

Joint Video Stitching and Stabilization from Moving Cameras.

PubMed

Guo, Heng; Liu, Shuaicheng; He, Tong; Zhu, Shuyuan; Zeng, Bing; Gabbouj, Moncef

2016-09-08

In this paper, we extend image stitching to video stitching for videos that are captured for the same scene simultaneously by multiple moving cameras. In practice, videos captured under this circumstance often appear shaky. Directly applying image stitching methods for shaking videos often suffers from strong spatial and temporal artifacts. To solve this problem, we propose a unified framework in which video stitching and stabilization are performed jointly. Specifically, our system takes several overlapping videos as inputs. We estimate both inter motions (between different videos) and intra motions (between neighboring frames within a video). Then, we solve an optimal virtual 2D camera path from all original paths. An enlarged field of view along the virtual path is finally obtained by a space-temporal optimization that takes both inter and intra motions into consideration. Two important components of this optimization are that (1) a grid-based tracking method is designed for an improved robustness, which produces features that are distributed evenly within and across multiple views, and (2) a mesh-based motion model is adopted for the handling of the scene parallax. Some experimental results are provided to demonstrate the effectiveness of our approach on various consumer-level videos and a Plugin, named "Video Stitcher" is developed at Adobe After Effects CC2015 to show the processed videos.

Preliminary Validation of a New Clinical Tool for Identifying Problem Video Game Playing

ERIC Educational Resources Information Center

King, Daniel Luke; Delfabbro, Paul H.; Zajac, Ian T.

2011-01-01

Research has estimated that between 6 to 13% of individuals who play video games do so excessively. However, the methods and definitions used to identify "problem" video game players often vary considerably. This research presents preliminary validation data for a new measure of problematic video game play called the Problem Video Game…

Using Video Records to Mediate Teaching Interns' Critical Reflection

ERIC Educational Resources Information Center

Scott, Sarah E.; Kucan, Linda; Correnti, Richard; Miller, Leigh A.

2013-01-01

In this study we investigated how the use of video records in a literacy methods course supports the development of reflective practitioners when video is a core element of the course design. Specifically, we detail how interns' video-based reflections provide evidence that the use of video records of teaching interns' promotes the development of…

47 CFR 79.2 - Accessibility of programming providing emergency information.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) BROADCAST RADIO SERVICES ACCESSIBILITY OF VIDEO PROGRAMMING Video Programming Owners, Providers, and... of programming providing emergency information. (1) Video programming distributors must make... or by using a method of visual presentation, as described in § 79.1. (2) Video programming...

Remote measurement of surface-water velocity using infrared videography and PIV: a proof-of-concept for Alaskan rivers

USGS Publications Warehouse

Kinzel, Paul J.; Legleiter, Carl; Nelson, Jonathan M.; Conaway, Jeffrey S.

2017-01-01

Thermal cameras with high sensitivity to medium and long wavelengths can resolve features at the surface of flowing water arising from turbulent mixing. Images acquired by these cameras can be processed with particle image velocimetry (PIV) to compute surface velocities based on the displacement of thermal features as they advect with the flow. We conducted a series of field measurements to test this methodology for remote sensing of surface velocities in rivers. We positioned an infrared video camera at multiple stations across bridges that spanned five rivers in Alaska. Simultaneous non-contact measurements of surface velocity were collected with a radar gun. In situ velocity profiles were collected with Acoustic Doppler Current Profilers (ADCP). Infrared image time series were collected at a frequency of 10Hz for a one-minute duration at a number of stations spaced across each bridge. Commercial PIV software used a cross-correlation algorithm to calculate pixel displacements between successive frames, which were then scaled to produce surface velocities. A blanking distance below the ADCP prevents a direct measurement of the surface velocity. However, we estimated surface velocity from the ADCP measurements using a program that normalizes each ADCP transect and combines those normalized transects to compute a mean measurement profile. The program can fit a power law to the profile and in so doing provides a velocity index, the ratio between the depth-averaged and surface velocity. For the rivers in this study, the velocity index ranged from 0.82 – 0.92. Average radar and extrapolated ADCP surface velocities were in good agreement with average infrared PIV calculations.

A Novel Method for Real-Time Audio Recording With Intraoperative Video.

PubMed

Sugamoto, Yuji; Hamamoto, Yasuyoshi; Kimura, Masayuki; Fukunaga, Toru; Tasaki, Kentaro; Asai, Yo; Takeshita, Nobuyoshi; Maruyama, Tetsuro; Hosokawa, Takashi; Tamachi, Tomohide; Aoyama, Hiromichi; Matsubara, Hisahiro

2015-01-01

Although laparoscopic surgery has become widespread, effective and efficient education in laparoscopic surgery is difficult. Instructive laparoscopy videos with appropriate annotations are ideal for initial training in laparoscopic surgery; however, the method we use at our institution for creating laparoscopy videos with audio is not generalized, and there have been no detailed explanations of any such method. Our objectives were to demonstrate the feasibility of low-cost simple methods for recording surgical videos with audio and to perform a preliminary safety evaluation when obtaining these recordings during operations. We devised a method for the synchronous recording of surgical video with real-time audio in which we connected an amplifier and a wireless microphone to an existing endoscopy system and its equipped video-recording device. We tested this system in 209 cases of laparoscopic surgery in operating rooms between August 2010 and July 2011 and prospectively investigated the results of the audiovisual recording method and examined intraoperative problems. Numazu City Hospital in Numazu city, Japan. Surgeons, instrument nurses, and medical engineers. In all cases, the synchronous input of audio and video was possible. The recording system did not cause any inconvenience to the surgeon, assistants, instrument nurse, sterilized equipment, or electrical medical equipment. Statistically significant differences were not observed between the audiovisual group and control group regarding the operating time, which had been divided into 2 slots-performed by the instructors or by trainees (p > 0.05). This recording method is feasible and considerably safe while posing minimal difficulty in terms of technology, time, and expense. We recommend this method for both surgical trainees who wish to acquire surgical skills effectively and medical instructors who wish to teach surgical skills effectively. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Video Image Stabilization and Registration

NASA Technical Reports Server (NTRS)

Hathaway, David H. (Inventor); Meyer, Paul J. (Inventor)

2002-01-01

A method of stabilizing and registering a video image in multiple video fields of a video sequence provides accurate determination of the image change in magnification, rotation and translation between video fields, so that the video fields may be accurately corrected for these changes in the image in the video sequence. In a described embodiment, a key area of a key video field is selected which contains an image which it is desired to stabilize in a video sequence. The key area is subdivided into nested pixel blocks and the translation of each of the pixel blocks from the key video field to a new video field is determined as a precursor to determining change in magnification, rotation and translation of the image from the key video field to the new video field.

Video Image Stabilization and Registration

NASA Technical Reports Server (NTRS)

Hathaway, David H. (Inventor); Meyer, Paul J. (Inventor)

2003-01-01

A method of stabilizing and registering a video image in multiple video fields of a video sequence provides accurate determination of the image change in magnification, rotation and translation between video fields, so that the video fields may be accurately corrected for these changes in the image in the video sequence. In a described embodiment, a key area of a key video field is selected which contains an image which it is desired to stabilize in a video sequence. The key area is subdivided into nested pixel blocks and the translation of each of the pixel blocks from the key video field to a new video field is determined as a precursor to determining change in magnification, rotation and translation of the image from the key video field to the new video field.

Use of a Bioactive Scaffold to Stimulate ACL Healing Also Minimizes Post-traumatic Osteoarthritis after Surgery

PubMed Central

Murray, Martha M.; Fleming, Braden C.

2013-01-01

Background While ACL reconstruction is the treatment gold standard for ACL injury, it does not reduce the risk of post-traumatic osteoarthritis. Therefore, new treatments that minimize this postoperative complication are of interest. Bio-enhanced ACL repair, in which a bioactive scaffold is used to stimulate healing of an ACL transection, has shown considerable promise in short term studies. The long-term results of this technique and the effects of the bio-enhancement on the articular cartilage have not been previously evaluated in a large animal model. Hypothesis 1) The structural (tensile) properties of the porcine ACL at 6 and 12 months after injury are similar when treated with bio-enhanced ACL repair, bio-enhanced ACL reconstruction, or conventional ACL reconstruction, and all treatments yield results superior to untreated ACL transection. 2) After one year, macroscopic cartilage damage following bio-enhanced ACL repair is similar to bio-enhanced ACL reconstruction and less than conventional ACL reconstruction and untreated ACL transection. Study Design Controlled laboratory study (porcine model) Methods Sixty-two Yucatan mini-pigs underwent ACL transection and randomization to four experimental groups: 1) no treatment, 2) conventional ACL reconstruction, 3) “bio-enhanced” ACL reconstruction using a bioactive scaffold, and 4) “bio-enhanced” ACL repair using a bioactive scaffold. The biomechanical properties of the ligament or graft and macroscopic assessments of the cartilage surfaces were performed after 6 and 12 months of healing. Results The structural properties (i.e., linear stiffness, yield and maximum loads) of the ligament following bio-enhanced ACL repair were not significantly different from bio-enhanced ACL reconstruction or conventional ACL reconstruction, but were significantly greater than untreated ACL transection after 12 months of healing. Macroscopic cartilage damage after bio-enhanced ACL repair was significantly less than untreated ACL transection and bio-enhanced ACL reconstruction, and there was a strong trend (p=.068) that it was less than conventional ACL reconstruction in the porcine model at 12 months. Conclusions Bio-enhanced ACL repair produces a ligament that is biomechanically similar to an ACL graft and provides chondroprotection to the joint following ACL surgery. Clinical Relevance Bio-enhanced ACL repair may provide a new less invasive treatment option that reduces cartilage damage following joint injury. PMID:23857883

YouTube is the Most Frequently Used Educational Video Source for Surgical Preparation.

PubMed

Rapp, Allison K; Healy, Michael G; Charlton, Mary E; Keith, Jerrod N; Rosenbaum, Marcy E; Kapadia, Muneera R

The purpose of this study was to evaluate surgical preparation methods of medical students, residents, and faculty with special attention to video usage. Following Institutional Review Board approval, anonymous surveys were distributed to participants. Information collected included demographics and surgical preparation methods, focusing on video usage. Participants were questioned regarding frequency and helpfulness of videos, video sources used, and preferred methods between videos, reading, and peer consultation. Statistical analysis was performed using SAS. Surveys were distributed to participants in the Department of Surgery at the University of Iowa Hospitals and Clinics, a tertiary care center in Iowa City, Iowa. Survey participants included fourth-year medical students pursuing general surgery, general surgery residents, and faculty surgeons in the Department of Surgery. A total of 86 surveys were distributed, and 78 surveys were completed. This included 42 learners (33 residents, 9 fourth-year medical students) and 36 faculty. The overall response rate was 91%; 90% of respondents reported using videos for surgical preparation (learners = 95%, faculty = 83%, p = NS). Regarding surgical preparation methods overall, most learners and faculty selected reading (90% versus 78%, p = NS), and fewer respondents reported preferring videos (64% versus 44%, p = NS). Faculty more often use peer consultation (31% versus 50%, p < 0.02). Among respondents who use videos (N = 70), the most used source was YouTube (86%). Learners and faculty use different video sources. Learners use YouTube and Surgical Council on Resident Education (SCORE) Portal more than faculty (YouTube: 95% versus 73%, p < 0.02; SCORE: 25% versus 7%, p < 0.05). Faculty more often use society web pages and commercial videos (society: 67% versus 38%, p < 0.03; commercial: 27% versus 5%, p < 0.02). Most respondents reported using videos to prepare for surgery. YouTube was the preferred source. Posting surgical videos to YouTube may allow for maximal access to learners who are preparing for surgical cases. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Comparing two remote video survey methods for spatial predictions of the distribution and environmental niche suitability of demersal fishes.

PubMed

Galaiduk, Ronen; Radford, Ben T; Wilson, Shaun K; Harvey, Euan S

2017-12-15

Information on habitat associations from survey data, combined with spatial modelling, allow the development of more refined species distribution modelling which may identify areas of high conservation/fisheries value and consequentially improve conservation efforts. Generalised additive models were used to model the probability of occurrence of six focal species after surveys that utilised two remote underwater video sampling methods (i.e. baited and towed video). Models developed for the towed video method had consistently better predictive performance for all but one study species although only three models had a good to fair fit, and the rest were poor fits, highlighting the challenges associated with modelling habitat associations of marine species in highly homogenous, low relief environments. Models based on baited video dataset regularly included large-scale measures of structural complexity, suggesting fish attraction to a single focus point by bait. Conversely, models based on the towed video data often incorporated small-scale measures of habitat complexity and were more likely to reflect true species-habitat relationships. The cost associated with use of the towed video systems for surveying low-relief seascapes was also relatively low providing additional support for considering this method for marine spatial ecological modelling.

Fast generation of video holograms of three-dimensional moving objects using a motion compensation-based novel look-up table.

PubMed

Kim, Seung-Cheol; Dong, Xiao-Bin; Kwon, Min-Woo; Kim, Eun-Soo

2013-05-06

A novel approach for fast generation of video holograms of three-dimensional (3-D) moving objects using a motion compensation-based novel-look-up-table (MC-N-LUT) method is proposed. Motion compensation has been widely employed in compression of conventional 2-D video data because of its ability to exploit high temporal correlation between successive video frames. Here, this concept of motion-compensation is firstly applied to the N-LUT based on its inherent property of shift-invariance. That is, motion vectors of 3-D moving objects are extracted between the two consecutive video frames, and with them motions of the 3-D objects at each frame are compensated. Then, through this process, 3-D object data to be calculated for its video holograms are massively reduced, which results in a dramatic increase of the computational speed of the proposed method. Experimental results with three kinds of 3-D video scenarios reveal that the average number of calculated object points and the average calculation time for one object point of the proposed method, have found to be reduced down to 86.95%, 86.53% and 34.99%, 32.30%, respectively compared to those of the conventional N-LUT and temporal redundancy-based N-LUT (TR-N-LUT) methods.

Automated Video Based Facial Expression Analysis of Neuropsychiatric Disorders

PubMed Central

Wang, Peng; Barrett, Frederick; Martin, Elizabeth; Milanova, Marina; Gur, Raquel E.; Gur, Ruben C.; Kohler, Christian; Verma, Ragini

2008-01-01

Deficits in emotional expression are prominent in several neuropsychiatric disorders, including schizophrenia. Available clinical facial expression evaluations provide subjective and qualitative measurements, which are based on static 2D images that do not capture the temporal dynamics and subtleties of expression changes. Therefore, there is a need for automated, objective and quantitative measurements of facial expressions captured using videos. This paper presents a computational framework that creates probabilistic expression profiles for video data and can potentially help to automatically quantify emotional expression differences between patients with neuropsychiatric disorders and healthy controls. Our method automatically detects and tracks facial landmarks in videos, and then extracts geometric features to characterize facial expression changes. To analyze temporal facial expression changes, we employ probabilistic classifiers that analyze facial expressions in individual frames, and then propagate the probabilities throughout the video to capture the temporal characteristics of facial expressions. The applications of our method to healthy controls and case studies of patients with schizophrenia and Asperger’s syndrome demonstrate the capability of the video-based expression analysis method in capturing subtleties of facial expression. Such results can pave the way for a video based method for quantitative analysis of facial expressions in clinical research of disorders that cause affective deficits. PMID:18045693

Quantitative histological grading methods to assess subchondral bone and synovium changes subsequent to medial meniscus transection in the rat

PubMed Central

Kloefkorn, Heidi E.; Allen, Kyle D.

2017-01-01

Aim of the Study The importance of the medial meniscus to knee health is demonstrated by studies which show meniscus injuries significantly increase the likelihood of developing osteoarthritis (OA), and knee OA can be modeled in rodents using simulated meniscus injuries. Traditionally, histological assessments of OA in these models have focused on damage to the articular cartilage; however, OA is now viewed as a disease of the entire joint as an organ system. The aim of this study was to develop quantitative histological measures of bone and synovial changes in a rat medial meniscus injury model of knee OA. Materials and Methods To initiate OA, a medial meniscus transection (MMT) and a medial collateral ligament transection (MCLT) were performed in 32 male Lewis rats (MMT group). MCLT alone served as the sham procedure in 32 additional rats (MCLT sham group). At weeks 1, 2, 4, and 6 post-surgery, histological assessment of subchondral bone and synovium was performed (n = 8 per group per time point). Results Trabecular bone area and the ossification width at the osteochondral interface increased in both the MMT and MCLT groups. Subintimal synovial cell morphology also changed in MMT and MCLT groups relative to naïve animals. Conclusions OA affects the joint as an organ system, and quantifying changes throughout an entire joint can improve our understanding of the relationship between joint destruction and painful OA symptoms following meniscus injury. PMID:27797605

Spatial patterns of bee captures in North American bowl trapping surveys

USGS Publications Warehouse

Droege, Sam; Tepedino, Vincent J.; Lebuhn, Gretchen; Link, William; Minckley, Robert L.; Chen, Qian; Conrad, Casey

2010-01-01

1. Bowl and pan traps are now commonly used to capture bees (Hymenoptera: Apiformes) for research and surveys. 2. Studies of how arrangement and spacing of bowl traps affect captures of bees are needed to increase the efficiency of this capture technique. 3. We present results from seven studies of bowl traps placed in trapping webs, grids, and transects in four North American ecoregions (Mid-Atlantic, Coastal California, Chihuahuan Desert, and Columbia Plateau). 4. Over 6000 specimens from 31 bee genera were captured and analysed across the studies. 5. Based on the results from trapping webs and distance tests, the per bowl capture rate of bees does not plateau until bowls are spaced 3–5 m apart. 6. Minor clumping of bee captures within transects was detected, with 26 of 56 transects having index of dispersion values that conform to a clumped distribution and 39 transects having positive Green's index values, 13 with zero, and only four negative. However, degree of clumping was slight with an average value of only 0.06 (the index ranges from -1 to 1) with only five values >0.15. Similarly, runs tests were significant for only 5.9% of the transects. 7. Results indicate that (i) capture rates are unaffected by short distances between bowls within transects and (ii) that bowls and transects should be dispersed throughout a study site.

Recovery of bimodal locomotion in the spinal-transected salamander, Pleurodeles waltlii.

PubMed

Chevallier, Stéphanie; Landry, Marc; Nagy, Frédéric; Cabelguen, Jean-Marie

2004-10-01

Electromyographic (EMG) analysis was used to provide an assessment of the recovery of locomotion in spinal-transected adult salamanders (Pleurodeles waltlii). EMG recordings were performed during swimming and overground stepping in the same animal before and at various times (up to 500 days) after a mid-trunk spinalization. Two-three weeks after spinalization, locomotor EMG activity was limited to the forelimbs and the body rostral to the transection. Thereafter, there was a return of the locomotor EMG activity at progressively more caudal levels below the transection. The animals reached stable locomotor patterns 3-4 months post-transection. Several locomotor parameters (cycle duration, burst duration, burst proportion, intersegmental phase lag, interlimb coupling) measured at various recovery times after spinalization were compared with those in intact animals. These comparisons revealed transient and long-term alterations in the locomotor parameters both above and below the transection site. These alterations were much more pronounced for swimming than for stepping and revealed differences in adaptive plasticity between the two locomotor networks. Recovered locomotor activity was immediately abolished by retransection at the site of the original spinalization, suggesting that the spinal cord caudal to the transection was reinnervated by descending brain and/or propriospinal axons, and that this regeneration contributed to the restoration of locomotor activity. Anatomical studies conducted in parallel further demonstrated that some of the regenerated axons came from glutamatergic and serotoninergic immunoreactive cells within the reticular formation.

A New Sample Transect through the Sierra Madre Occidental Silicic Large Igneous Province in Southern Chihuahua State, Mexico: First Stratigraphic, Petrologic, and Geochemical Results

NASA Astrophysics Data System (ADS)

Andrews, G. D.; Davila Harris, P.; Brown, S. R.; Anderson, L.; Moreno, N.

2014-12-01

We completed a field sampling transect across the northern Sierra Madre Occidental silicic large igneous province (SMO) in December 2013. Here we present the first stratigraphic, petrological, and geochemical data from the transect between Hidalgo del Parral and Guadalupe y Calvo, Chihuahua, Mexico. This is the first new transect across the SMO in 25 years and the only one between existing NE - SW transects at Chihuahua - Hermosillo and Durango - Mazatlan. The 245 km-long transect along Mexican Highway 24 crosses the boundary between the extended (Basin and Range) and non-extended (Sierra Madre Occidental plateau) parts of the SMO, and allows sampling of previously undescribed Oligocene (?) - early Miocene (?) rhyolitic ignimbrites and lavas, and occasional post-rhyolite, Miocene (?) SCORBA basaltic andesite lavas. 54 samples of rhyolitic ignimbrites (40) and lavas (7), and basaltic andesite lavas (7) were sampled along the transect, including 8 canyon sections with more than one unit. The ignimbrites are overwhelming rhyodacitic (plagioclase and hornblende or biotite phyric) or rhyolitic (quartz (+/- sanidine) in additon to plagioclase and hornblende or biotite phyric) and sparsely to highly phyric. Preliminary petrographic (phenocryst abundances) and geochemical (major and trace element) will be presented and compared to existing data from elsewhere in the SMO. Future work will include U-Pb zircon dating and whole rock and in-zircon radiogenic isotopes analyses.

Swimming behaviour and calcium incorporation into inner ear otoliths of fish after vestibular nerve transection

NASA Astrophysics Data System (ADS)

Edelmann, E.; Anken, R. H.; Rahmann, H.

2004-01-01

Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium tracer alizarin complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated. Like most neonate swordtails, Type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal, and the otolithic calcium incorporation in controls of the same batch was symmetric. In Type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetric. These results show that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. In conclusion, the regulation of otolithic calcium incorporation is guided neuronally, in part via the vestibular nerve and, in part, via a further pathway, which remains to be addressed in the course of future investigations.

Swimming Behavior and Calcium Incorporation into inner Ear Otoliths of Fish after vestibular Nerve Transection

NASA Astrophysics Data System (ADS)

Edelmann, E.; Anken, R.; Rahmann, H.

Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium-tracer alizarin- complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated: Like neonate swordtails, type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal and the otolithic calcium incorporation in controls of the same batch was symmetrical. In type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetrical. These results stongly suggest that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. Thus, it is assumed that the mechanisms regulating otolith growth and equlibibrium differ in the two types of cichlid fish. This work was financially supported by the German Aerospace Center (DLR) e.V. (FKZ: 50 WB 9997).

News video story segmentation method using fusion of audio-visual features

NASA Astrophysics Data System (ADS)

Wen, Jun; Wu, Ling-da; Zeng, Pu; Luan, Xi-dao; Xie, Yu-xiang

2007-11-01

News story segmentation is an important aspect for news video analysis. This paper presents a method for news video story segmentation. Different form prior works, which base on visual features transform, the proposed technique uses audio features as baseline and fuses visual features with it to refine the results. At first, it selects silence clips as audio features candidate points, and selects shot boundaries and anchor shots as two kinds of visual features candidate points. Then this paper selects audio feature candidates as cues and develops different fusion method, which effectively using diverse type visual candidates to refine audio candidates, to get story boundaries. Experiment results show that this method has high efficiency and adaptability to different kinds of news video.

Deep visual-semantic for crowded video understanding

NASA Astrophysics Data System (ADS)

Deng, Chunhua; Zhang, Junwen

2018-03-01

Visual-semantic features play a vital role for crowded video understanding. Convolutional Neural Networks (CNNs) have experienced a significant breakthrough in learning representations from images. However, the learning of visualsemantic features, and how it can be effectively extracted for video analysis, still remains a challenging task. In this study, we propose a novel visual-semantic method to capture both appearance and dynamic representations. In particular, we propose a spatial context method, based on the fractional Fisher vector (FV) encoding on CNN features, which can be regarded as our main contribution. In addition, to capture temporal context information, we also applied fractional encoding method on dynamic images. Experimental results on the WWW crowed video dataset demonstrate that the proposed method outperform the state of the art.

Modeling the time--varying subjective quality of HTTP video streams with rate adaptations.

PubMed

Chen, Chao; Choi, Lark Kwon; de Veciana, Gustavo; Caramanis, Constantine; Heath, Robert W; Bovik, Alan C

2014-05-01

Newly developed hypertext transfer protocol (HTTP)-based video streaming technologies enable flexible rate-adaptation under varying channel conditions. Accurately predicting the users' quality of experience (QoE) for rate-adaptive HTTP video streams is thus critical to achieve efficiency. An important aspect of understanding and modeling QoE is predicting the up-to-the-moment subjective quality of a video as it is played, which is difficult due to hysteresis effects and nonlinearities in human behavioral responses. This paper presents a Hammerstein-Wiener model for predicting the time-varying subjective quality (TVSQ) of rate-adaptive videos. To collect data for model parameterization and validation, a database of longer duration videos with time-varying distortions was built and the TVSQs of the videos were measured in a large-scale subjective study. The proposed method is able to reliably predict the TVSQ of rate adaptive videos. Since the Hammerstein-Wiener model has a very simple structure, the proposed method is suitable for online TVSQ prediction in HTTP-based streaming.

Videos Determine the Moon's "g"

ERIC Educational Resources Information Center

Persson, J. R.; Hagen, J. E.

2011-01-01

Determining the acceleration of a free-falling object due to gravity is a standard experiment in physics. Different methods to do this have been developed over the years. This article discusses the use of video-analysis tools as another method. If there is a video available and a known scale it is possible to analyse the motion. The use of video…

Biodiversity of seagrass bed in Balanan Resort - Baluran National Park

NASA Astrophysics Data System (ADS)

Soedarti, T.; Hariyanto, S.; Wedayanti, A.; Rahmawati, A. D.; Safitri, D. P.; Alificia, R. I.; Suwono

2017-09-01

Seagrass beds are flowering plants that live on the seabed. Seagrass provides a habitat for diverse flora and fauna, spawning ground, nursery ground, raising ground, and feeding ground. Balanan Resort - Baluran National Park has many beaches, such as Kajang Beach, Si Banjir Beach, Kakapa Beach, and Serondo Beach. This study was aimed to determine species composition, seagrass dominated, and the diversity index of seagrass and substrate in Resort Balanan - Baluran National Park. This research was carried out in Kajang Beach, Sibanjir Beach, Kakapa Beach, and Sirondo Beach from August to September 2015 using belt transect method, each transect consists of 15 plots (19 transects = 285 plots) and using the frame of 1x1 m. This research found seven genera and ten species : Cymodoce (C rotundata and C. serrulata), Syringodium (S. isoelifolium), Thallassodendron (T. ciliatum), Enhalus (E. acoroides) , Halodule (H. univernis and H. pinifolia), Halophila (H. ovalis and H. decipiens), and Thalassia (T. hemprichii). The diversity index of seagrass bed was moderate [H'=1.90] in Balanan Resort. The substrate of seagrass bed was mud, gravel, sand, clay sand and rubble in Balanan Resort. The dominance index was near zero [C = 0.194], that means no dominant species.

Strip transect sampling and analysis for avian habitat studies

Treesearch

Richard N. Conner; James G. Dickson

1980-01-01

Censusing procedures that detect effects of habitat treatment on birds are outlined. We suggest that only relative values of bird species diversity, equitability, abundance, and species richness need be obtained. We also suggest that 4, 250-m strip transects per treatment and 8-10 trips over each transect are adequate. Aspects of sampling design that affect within-...

The bathypelagic community of Monterey Canyon

NASA Astrophysics Data System (ADS)

Robison, Bruce H.; Sherlock, Rob E.; Reisenbichler, Kim R.

2010-08-01

We used a quiet, deep-diving remotely operated vehicle (ROV) to conduct oblique, quantitative video transects of the bathypelagic fauna at depths between 1000 and 3500 m at a site over the Monterey Submarine Canyon, in the eastern North Pacific off central California. Fifteen such dives were made over a two-year period. Analyses of the video data revealed a rich and diverse fauna dominated by gelatinous animals. In particular, the holopelagic polychaete Poeobius meseres was an important detritivore in the upper half of this depth range. As Poeobius abundance eventually declined with increasing depth, larvacean abundance increased. In contrast, the relative numbers of crustacean grazers, principally copepods and mysids, remained relatively constant with depth. Medusae were most abundant and most diverse among the gelatinous predators, which also included ctenophores, and siphonophores. Chaetognaths occurred chiefly in the upper half of the depth range. While there is considerable overlap, the bathypelagic fauna can be separated into upper (1000 to 2300 m) and lower (2400 to 3300 m) zones, as well as a distinct and populous benthic boundary layer. Within the overall bathypelagic community is a complex web of trophic links involving gelatinous predators that feed on both gelatinous and hard-bodied particle feeders, as well as on each other. The amount of organic carbon contained in this jelly web is substantial but its ecological fate is uncertain. The assessment of bathypelagic communities will be important for establishing baselines to conserve deep pelagic biodiversity within high-seas protected areas.

The 2014 summer coral bleaching event in subtropical Hong Kong.

PubMed

Xie, James Y; Lau, Dickey C C; Kei, Keith; Yu, Vriko P F; Chow, Wing-Kuen; Qiu, Jian-Wen

2017-11-30

We reported a coral bleaching event that occurred in August-September 2014 in Hong Kong waters based on video transect surveys conducted at eight sites. The bleaching affected eight species of corals with different growth forms. Bleaching at seven of the eight study sites was minor, affecting only 0.4-5.2% colonies and 0.8-10.0% coral-covered area. Sharp Island East, however, suffered from a moderate level of bleaching, with 13.1% colonies and 30.1% coral-covered area affected. Examination of the government's environmental monitoring data indicated abnormal water quality conditions preceding and during the bleaching event. Follow-up field surveys of tagged colonies showed that 76% of them had fully recovered, 12% partially recovered, and 12% suffered from mortality. These results indicate that the subtropical corals of Hong Kong are not immune to bleaching, and there is a need to study their responses under climate change scenarios. Copyright © 2017 Elsevier Ltd. All rights reserved.

Role of banding in forest conservation strategy in eastern Guatemala

USGS Publications Warehouse

Robbins, C.S.; Dowell, B.A.; Arias, I.; Cerezo B., A.

1999-01-01

In response to a request from FUNDAECO, a Guatemalan non-government organization, we worked with them to develop a conservation strategy for the Cerro San Gil Protected Area and surrounding private lands. Volunteer banders from a dozen states and Canadian provinces assisted in long-term monitoring of populations of resident and migratory species through banding and point counts. Guatemalan students were trained to continue the research and initiate other conservation projects. Banding data helped demonstrate habitat and elevational affiliations, effects of habitat fragmentation, site fidelity, survival rates, local movements, and presence of rare species not otherwise detected. Banding was also an excellent teaching tool and provided videos for conservation programs on Guatemala national television. Roadside and off-road Breeding Bird Survey transects were used to map distribution of breeding species on habitat maps derived from satellite imagery, and point count surveys on private lands were used to identify prime habitats that warrant protection through conservation easements--a new concept for Central America.

Surficial geology and benthic habitat of the German Bank seabed, Scotian Shelf, Canada

USGS Publications Warehouse

Todd, Brian J.; Kostylev, Vladimir E.

2011-01-01

To provide the scientific context for management of a newly opened scallop fishing ground, surficial geology and benthic habitats were mapped on German Bank on the southern Scotian Shelf off Atlantic Canada. To provide a seamless regional dataset, multibeam sonar surveys covered 5320 sqaure kilometres of the bank in water depths of 30–250 m and provided 5 m horizontal resolution bathymetry and backscatter strength. Geoscience data included high-resolution geophysical profiles (seismic reflection and sidescan sonar) and seabed sediment samples. Geological interpretation and is overlain in places by glacial and postglacial sediment. Biological data included seafloor video transects and photographs from which 127 taxa of visible megabenthos were identified. Trawl bycatch data were obtained from government annual research surveys. Statistical analysis of revealed that bedrock is exposed at the seafloor on much of German Bankthese two datasets and a suite of oceanographic environmental variables demonstrated that significantly different fauna exist on bedrock, glacial sediment and postglacial sediment.

Perceptions of sexual coercion among young women in Uganda.

PubMed

Hayer, Manvir Kaur

2010-01-01

This paper sets out to explore Ugandan young women's definitions and perceptions of sexual coercion. A qualitative study was conducted with seven young women in rural Uganda. Participants filmed videos, wrote stories, made drawings and participated in transect walks before analysing their data through formal and informal discussions. Forced sex is defined narrowly to mean only rape. Verbal forms of sexual coercion were recognised, but only after some discussion. Verbal coercion is referred to as "abusing" or "convincing". Young women are commonly pressured into consenting to have sex, despite what they really want, owing to the socio-cultural circumstances. Young women in Uganda are significantly tolerant of sexual coercion. This tolerance appears to arise from power differentials between genders, and the socio-cultural environment shaping their lives. The paper improves understanding of young women's definitions and perceptions of sexual coercion, which is essential to provide effective violence prevention programmes. It also suggests that further research is warranted in this field.

Comparing High Definition Live Interactive and Store-and-Forward Consultations to In-Person Examinations

PubMed Central

Locatis, Craig; Burges, Gene; Maisiak, Richard; Liu, Wei-Li; Ackerman, Michael

2017-01-01

Abstract Background: There is little teledermatology research directly comparing remote methods, even less research with two in-person dermatologist agreement providing a baseline for comparing remote methods, and no research using high definition video as a live interactive method. Objective: To compare in-person consultations with store-and-forward and live interactive methods, the latter having two levels of image quality. Methods: A controlled study was conducted where patients were examined in-person, by high definition video, and by store-and-forward methods. The order patients experienced methods and residents assigned methods rotated, although an attending always saw patients in-person. The type of high definition video employed, lower resolution compressed or higher resolution uncompressed, was alternated between clinics. Primary and differential diagnoses, biopsy recommendations, and diagnostic and biopsy confidence ratings were recorded. Results: Concordance and confidence were significantly better for in-person versus remote methods and biopsy recommendations were lower. Store-and-forward and higher resolution uncompressed video results were similar and better than those for lower resolution compressed video. Limitations: Dermatology residents took store-and-forward photos and their quality was likely superior to those normally taken in practice. There were variations in expertise between the attending and second and third year residents. Conclusion: The superiority of in-person consultations suggests the tendencies to order more biopsies or still see patients in-person are often justified in teledermatology and that high resolution uncompressed video can close the resolution gap between store-and-forward and live interactive methods. PMID:27705083

Comparison of methods to monitor the distribution and impacts of unauthorized travel routes in a border park

USGS Publications Warehouse

Esque, Todd C.; Inman, Rich; Nussear, Kenneth E.; Webb, Robert; Girard, M.M.; DeGayner, J.

2016-01-01

The distribution and abundance of human-caused disturbances vary greatly through space and time and are cause for concern among land stewards in natural areas of the southwestern border-lands between the USA and Mexico. Human migration and border protection along the international boundary create Unauthorized Trail and Road (UTR) networks across National Park Service lands and other natural areas. UTRs may cause soil erosion and compaction, damage to vegetation and cultural resources, and may stress wildlife or impede their movements. We quantify the density and severity of UTR disturbances in relation to soils, and compare the use of previously established targeted trail assessments (hereafter — targeted assessments) against randomly placed transects to detect trail densities at Coronado National Memorial in Arizona in 2011. While trail distributions were similar between methods, targeted assessments estimated a large portion of the park to have the lowest density category (0–5 trail encounters per/km2), whereas the random transects in 2011 estimated more of the park as having the higher density categories (e.g., 15–20 encounters per km2category). Soil vulnerability categories that were assigned, a priori, based on published soil texture and composition did not accurately predict the impact of UTRs on soil, indicating that empirical methods may be better suited for identifying severity of compaction. While the estimates of UTR encounter frequencies were greater using the random transects than the targeted assessments for a relatively short period of time, it is difficult to determine whether this difference is dependent on greater cross-border activity, differences in technique, or from confounding environmental factors. Future surveys using standardized sampling techniques would increase accuracy.

Intraocular Lens Fragmentation Using Femtosecond Laser: An In Vitro Study

PubMed Central

Bala, Chandra; Shi, Jeffrey; Meades, Kerrie

2015-01-01

Purpose: To transect intraocular lenses (IOLs) using a femtosecond laser in cadaveric human eyes. To determine the optimal in vitro settings, to detect and characterize gasses or particles generated during this process. Methods: A femtosecond laser was used to transect hydrophobic and hydrophilic acrylic lenses. The settings required to enable easy separation of the lens fragment were determined. The gasses and particles generated were analysed using gas chromatography mass spectrometer (GC-MS) and total organic carbon analyzer (TOC), respectively. Results: In vitro the IOL fragments easily separated at the lowest commercially available energy setting of 1 μJ, 8-μm spot, and 2-μm line separation. No particles were detected in the 0.5- to 900-μm range. No significant gasses or other organic breakdown by products were detected at this setting. At much higher energy levels 12 μJ (4 × 6 μm spot and line separation) significant pyrolytic products were detected, which could be harmful to the eye. In cadaveric explanted IOL capsule complex the laser pulses could be applied through the capsule to the IOL and successfully fragment the IOL. Conclusion: IOL transection is feasible with femtosecond lasers. Further in vivo animal studies are required to confirm safety. Translational Relevance: In clinical practice there are a number of large intraocular lenses that can be difficult to explant. This in-vitro study examines the possibility of transecting the lasers quickly using femtosecond lasers. If in-vivo studies are successful, then this innovation could help ophthalmic surgeons in IOL explantation. PMID:26101721

Histomorphometric and Ultrastructural Evaluation of Long-Term Alpha Lipoic Acid and Vitamin B12 Use After Experimental Sciatic Nerve Injury in Rats.

PubMed

Arikan, Murat; Togral, Guray; Hasturk, Askin Esen; Horasanli, Bahriye; Helvacioglu, Fatma; Dagdeviren, Atilla; Tekindal, Mustafa Agah; Parpucu, Murat

2016-01-01

To analyze the therapeutic effects of long-term alpha lipoic acid (A-LA) and vitamin B12 use via histomorphometric methods and electron microscopy in the transected sciatic nerves of rats. Forty rats were randomized into five groups (n=8/group). In group I, 1 cm segment of sciatic nerve was resected without any other intervention. In group II (sham), following right sciatic nerve transection, primary epineurial anastomosis was performed by placing the edges of the nerve end-to-end. In group III (saline), after right sciatic nerve transection, the ends of the nerves were brought together and closed after application of intraperitoneal physiologic saline. In group IV, 2 mg/kg of alpha lipoic acid and in group V, 2 mg/kg of vitamin B12 was administered intraperitoneally before surgical intervention. Histomorphometric and electron microscopic analyses revealed that vitamin B12 did not prevent structural changes, abnormal myelination and g-ratio deviations regarding the functional aspects of the sciatic nerve. Alpha lipoic acid was more effective in restructuring the histomorphometric and structural aspects of the nerve with more myelinated fibers with optimal values (0.55-0.68) than vitamin B12 groups, in which the number of myelinated nerve fibers significantly decreased at optimal intervals (0.55-0.68). A-LA administration following peripheral nerve transection injury is more effective in promoting nerve healing regarding the structural aspects of the sciatic nerve compared to vitamin B12 and also myelination of nerve fibers by increasing g-values.

Determining Optimal Location and Numbers of Sample Transects for Characterization of UXO Sites

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

BILISOLY, ROGER L.; MCKENNA, SEAN A.

2003-01-01

Previous work on sample design has been focused on constructing designs for samples taken at point locations. Significantly less work has been done on sample design for data collected along transects. A review of approaches to point and transect sampling design shows that transects can be considered as a sequential set of point samples. Any two sampling designs can be compared through using each one to predict the value of the quantity being measured on a fixed reference grid. The quality of a design is quantified in two ways: computing either the sum or the product of the eigenvalues ofmore » the variance matrix of the prediction error. An important aspect of this analysis is that the reduction of the mean prediction error variance (MPEV) can be calculated for any proposed sample design, including one with straight and/or meandering transects, prior to taking those samples. This reduction in variance can be used as a ''stopping rule'' to determine when enough transect sampling has been completed on the site. Two approaches for the optimization of the transect locations are presented. The first minimizes the sum of the eigenvalues of the predictive error, and the second minimizes the product of these eigenvalues. Simulated annealing is used to identify transect locations that meet either of these objectives. This algorithm is applied to a hypothetical site to determine the optimal locations of two iterations of meandering transects given a previously existing straight transect. The MPEV calculation is also used on both a hypothetical site and on data collected at the Isleta Pueblo to evaluate its potential as a stopping rule. Results show that three or four rounds of systematic sampling with straight parallel transects covering 30 percent or less of the site, can reduce the initial MPEV by as much as 90 percent. The amount of reduction in MPEV can be used as a stopping rule, but the relationship between MPEV and the results of excavation versus no-further-action decisions is site specific and cannot be calculated prior to the sampling. It may be advantageous to use the reduction in MPEV as a stopping rule for systematic sampling across the site that can then be followed by focused sampling in areas identified has having UXO during the systematic sampling. The techniques presented here provide answers to the questions of ''Where to sample?'' and ''When to stop?'' and are capable of running in near real time to support iterative site characterization campaigns.« less

Dynamic video encryption algorithm for H.264/AVC based on a spatiotemporal chaos system.

PubMed

Xu, Hui; Tong, Xiao-Jun; Zhang, Miao; Wang, Zhu; Li, Ling-Hao

2016-06-01

Video encryption schemes mostly employ the selective encryption method to encrypt parts of important and sensitive video information, aiming to ensure the real-time performance and encryption efficiency. The classic block cipher is not applicable to video encryption due to the high computational overhead. In this paper, we propose the encryption selection control module to encrypt video syntax elements dynamically which is controlled by the chaotic pseudorandom sequence. A novel spatiotemporal chaos system and binarization method is used to generate a key stream for encrypting the chosen syntax elements. The proposed scheme enhances the resistance against attacks through the dynamic encryption process and high-security stream cipher. Experimental results show that the proposed method exhibits high security and high efficiency with little effect on the compression ratio and time cost.

Enhance Video Film using Retnix method

NASA Astrophysics Data System (ADS)

Awad, Rasha; Al-Zuky, Ali A.; Al-Saleh, Anwar H.; Mohamad, Haidar J.

2018-05-01

An enhancement technique used to improve the studied video quality. Algorithms like mean and standard deviation are used as a criterion within this paper, and it applied for each video clip that divided into 80 images. The studied filming environment has different light intensity (315, 566, and 644Lux). This different environment gives similar reality to the outdoor filming. The outputs of the suggested algorithm are compared with the results before applying it. This method is applied into two ways: first, it is applied for the full video clip to get the enhanced film; second, it is applied for every individual image to get the enhanced image then compiler them to get the enhanced film. This paper shows that the enhancement technique gives good quality video film depending on a statistical method, and it is recommended to use it in different application.

Using Digital Videos to Enhance Teacher Preparation

ERIC Educational Resources Information Center

Dymond, Stacy K.; Bentz, Johnell L.

2006-01-01

The technology to produce high quality, digital videos is widely available, yet its use in teacher preparation remains largely overlooked. A digital video library was created to augment instruction in a special education methods course for preservice elementary education teachers. The videos illustrated effective strategies for working with…

75 FR 7368 - Closed Captioning of Video Programming

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-19

... Captioning of Video Programming AGENCY: Federal Communications Commission. ACTION: Final rule. SUMMARY: In this document, the Commission amends the closed captioning rules to add another method by which video... . SUPPLEMENTARY INFORMATION: This is a summary of the Commission's document FCC 09-109, Closed Captioning of Video...

Intra prediction using face continuity in 360-degree video coding

NASA Astrophysics Data System (ADS)

Hanhart, Philippe; He, Yuwen; Ye, Yan

2017-09-01

This paper presents a new reference sample derivation method for intra prediction in 360-degree video coding. Unlike the conventional reference sample derivation method for 2D video coding, which uses the samples located directly above and on the left of the current block, the proposed method considers the spherical nature of 360-degree video when deriving reference samples located outside the current face to which the block belongs, and derives reference samples that are geometric neighbors on the sphere. The proposed reference sample derivation method was implemented in the Joint Exploration Model 3.0 (JEM-3.0) for the cubemap projection format. Simulation results for the all intra configuration show that, when compared with the conventional reference sample derivation method, the proposed method gives, on average, luma BD-rate reduction of 0.3% in terms of the weighted spherical PSNR (WS-PSNR) and spherical PSNR (SPSNR) metrics.

Robust and Imperceptible Watermarking of Video Streams for Low Power Devices

NASA Astrophysics Data System (ADS)

Ishtiaq, Muhammad; Jaffar, M. Arfan; Khan, Muhammad A.; Jan, Zahoor; Mirza, Anwar M.

With the advent of internet, every aspect of life is going online. From online working to watching videos, everything is now available on the internet. With the greater business benefits, increased availability and other online business advantages, there is a major challenge of security and ownership of data. Videos downloaded from an online store can easily be shared among non-intended or unauthorized users. Invisible watermarking is used to hide copyright protection information in the videos. The existing methods of watermarking are less robust and imperceptible and also the computational complexity of these methods does not suit low power devices. In this paper, we have proposed a new method to address the problem of robustness and imperceptibility. Experiments have shown that our method has better robustness and imperceptibility as well as our method is computationally efficient than previous approaches in practice. Hence our method can easily be applied on low power devices.

Can roads be used as transects for primate population surveys?.

PubMed

Hilário, Renato R; Rodrigues, Flávio H G; Chiarello, Adriano G; Mourthé, Italo

2012-01-01

Line transect distance sampling (LTDS) can be applied to either trails or roads. However, it is likely that sampling along roads might result in biased density estimates. In this paper, we compared the results obtained with LTDS applied on trails and roads for two primate species (Callithrix penicillata and Callicebus nigrifrons) to clarify whether roads are appropriate transects to estimate densities. We performed standard LTDS surveys in two nature reserves in south-eastern Brazil. Effective strip width and population density were different between trails and roads for C. penicillata, but not for C. nigrifrons. The results suggest that roads are not appropriate for use as transects in primate surveys, at least for some species. Further work is required to fully understand this issue, but in the meantime we recommend that researchers avoid using roads as transects or treat roads and trails as covariates when sampling on roads is unavoidable. Copyright © 2012 S. Karger AG, Basel.

Content-based video retrieval by example video clip

NASA Astrophysics Data System (ADS)

Dimitrova, Nevenka; Abdel-Mottaleb, Mohamed

1997-01-01

This paper presents a novel approach for video retrieval from a large archive of MPEG or Motion JPEG compressed video clips. We introduce a retrieval algorithm that takes a video clip as a query and searches the database for clips with similar contents. Video clips are characterized by a sequence of representative frame signatures, which are constructed from DC coefficients and motion information (`DC+M' signatures). The similarity between two video clips is determined by using their respective signatures. This method facilitates retrieval of clips for the purpose of video editing, broadcast news retrieval, or copyright violation detection.

AUDIOVISUAL RESOURCES ON THE TEACHING PROCESS IN SURGICAL TECHNIQUE

PubMed Central

PUPULIM, Guilherme Luiz Lenzi; IORIS, Rafael Augusto; GAMA, Ricardo Ribeiro; RIBAS, Carmen Australia Paredes Marcondes; MALAFAIA, Osvaldo; GAMA, Mirnaluci

2015-01-01

Background: The development of didactic means to create opportunities to permit complete and repetitive viewing of surgical procedures is of great importance nowadays due to the increasing difficulty of doing in vivo training. Thus, audiovisual resources favor the maximization of living resources used in education, and minimize problems arising only with verbalism. Aim: To evaluate the use of digital video as a pedagogical strategy in surgical technique teaching in medical education. Methods: Cross-sectional study with 48 students of the third year of medicine, when studying in the surgical technique discipline. They were divided into two groups with 12 in pairs, both subject to the conventional method of teaching, and one of them also exposed to alternative method (video) showing the technical details. All students did phlebotomy in the experimental laboratory, with evaluation and assistance of the teacher/monitor while running. Finally, they answered a self-administered questionnaire related to teaching method when performing the operation. Results: Most of those who did not watch the video took longer time to execute the procedure, did more questions and needed more faculty assistance. The total exposed to video followed the chronology of implementation and approved the new method; 95.83% felt able to repeat the procedure by themselves, and 62.5% of those students that only had the conventional method reported having regular capacity of technique assimilation. In both groups mentioned having regular difficulty, but those who have not seen the video had more difficulty in performing the technique. Conclusion: The traditional method of teaching associated with the video favored the ability to understand and transmitted safety, particularly because it is activity that requires technical skill. The technique with video visualization motivated and arouse interest, facilitated the understanding and memorization of the steps for procedure implementation, benefiting the students performance. PMID:26734790

Enhancing the control of force in putting by video game training.

PubMed

Fery, Y A; Ponserre, S

2001-10-10

Even if golf video games provide no proprioceptive afferences on actual putting movement, they may give sufficient substitutive visual cues to enhance force control in this skill. It was hypothesized that this usefulness requires, however, two conditions: the video game must provide reliable demonstrations of actual putts, and the user must want to use the game to make progress in actual putting. Accordingly, a video game was selected on the basis of its fidelity to the real-world game. It allowed two different methods of adjusting the virtual player's putting force in order to hole a putt: an analogue method that consisted of focusing on the virtual player's movement and a symbolic method that consisted of focusing on the movement of a gauge on a scale representing the virtual player's putting force. The participants had to use one of these methods with either the intention of making progress in actual putting or in a second condition to simply enjoy the game. Results showed a positive transfer of video playing to actual putting skill for the learning group and also, to a lesser degree, for the enjoyment group; but only when they used the symbolic method. Results are discussed in the context of how vision may convey force cues in sports video games.

Diavideos: a diabetes health video portal.

PubMed

Sánchez-Bocanegra, C L; Rivero-Rodriguez, A; Fernández-Luque, L; Sevillano, J L

2013-01-01

Diavideos is a web platform that collects trustworthy diabetes health videos from YouTube and offers them in a easy way. YouTube is a big repository of health videos, but good content is sometimes mixed with misleading and harmful videos such as promoting anorexia [1]. Diavideos is a web portal that provides easy access to a repository of trustworthy diabetes videos. This poster describes Diavideos and explains the crawling method used to retrieve these videos from trusted channels.

How the "Understanding Research Evidence" Web-Based Video Series From the National Collaborating Centre for Methods and Tools Contributes to Public Health Capacity to Practice Evidence-Informed Decision Making: Mixed-Methods Evaluation.

PubMed

Chan, Linda; Mackintosh, Jeannie; Dobbins, Maureen

2017-09-28

The National Collaborating Centre for Methods and Tools (NCCMT) offers workshops and webinars to build public health capacity for evidence-informed decision-making. Despite positive feedback for NCCMT workshops and resources, NCCMT users found key terms used in research papers difficult to understand. The Understanding Research Evidence (URE) videos use plain language, cartoon visuals, and public health examples to explain complex research concepts. The videos are posted on the NCCMT website and YouTube channel. The first four videos in the URE web-based video series, which explained odds ratios (ORs), confidence intervals (CIs), clinical significance, and forest plots, were evaluated. The evaluation examined how the videos affected public health professionals' practice. A mixed-methods approach was used to examine the delivery mode and the content of the videos. Specifically, the evaluation explored (1) whether the videos were effective at increasing knowledge on the four video topics, (2) whether public health professionals were satisfied with the videos, and (3) how public health professionals applied the knowledge gained from the videos in their work. A three-part evaluation was conducted to determine the effectiveness of the first four URE videos. The evaluation included a Web-based survey, telephone interviews, and pretest and posttests, which evaluated public health professionals' experience with the videos and how the videos affected their public health work. Participants were invited to participate in this evaluation through various open access, public health email lists, through informational flyers and posters at the Canadian Public Health Association (CPHA) conference, and through targeted recruitment to NCCMT's network. In the Web-based surveys (n=46), participants achieved higher scores on the knowledge assessment questions from watching the OR (P=.04), CI (P=.04), and clinical significance (P=.05) videos but not the forest plot (P=.12) video, as compared with participants who had not watched the videos. The pretest and posttest (n=124) demonstrated that participants had a better understanding of forest plots (P<.001) and CIs (P<.001) after watching the videos. Due to small sample size numbers, there were insufficient pretest and posttest data to conduct meaningful analyses on the clinical significance and OR videos. Telephone interview participants (n=18) thought the videos' use of animation, narration, and plain language was appropriate for people with different levels of understanding and learning styles. Participants felt that by increasing their understanding of research evidence, they could develop better interventions and design evaluations to measure the impact of public health initiatives. Overall, the results of the evaluation showed that watching the videos resulted in an increase in knowledge, and participants had an overall positive experience with the URE videos. With increased competence in using the best available evidence, professionals are empowered to contribute to decisions that can improve health outcomes of communities. ©Linda Chan, Jeannie Mackintosh, Maureen Dobbins. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 28.09.2017.

Online and unsupervised face recognition for continuous video stream

NASA Astrophysics Data System (ADS)

Huo, Hongwen; Feng, Jufu

2009-10-01

We present a novel online face recognition approach for video stream in this paper. Our method includes two stages: pre-training and online training. In the pre-training phase, our method observes interactions, collects batches of input data, and attempts to estimate their distributions (Box-Cox transformation is adopted here to normalize rough estimates). In the online training phase, our method incrementally improves classifiers' knowledge of the face space and updates it continuously with incremental eigenspace analysis. The performance achieved by our method shows its great potential in video stream processing.

Review of Video Prompting Studies for Persons with Developmental Disabilities

ERIC Educational Resources Information Center

Banda, Devender R.; Dogoe, Maud S.; Matuszny, Rose Marie

2011-01-01

We reviewed 18 video prompting studies that were conducted with persons with developmental disabilities. Results across the studies indicate that video prompting is a viable method for improving various domestic, vocational, and independent living skills. In addition, video prompting strategies facilitated maintenance and generalization of learned…

Evaluation of Meniscal Mechanics and Proteoglycan Content in a Modified Anterior Cruciate Ligament Transection Model

PubMed Central

Fischenich, Kristine M.; Coatney, Garrett A.; Haverkamp, John H.; Button, Keith D.; DeCamp, Charlie; Haut, Roger C.; Haut Donahue, Tammy L.

2014-01-01

Post-traumatic osteoarthritis (PTOA) develops as a result of traumatic loading that causes tears of the soft tissues in the knee. A modified transection model, where the anterior cruciate ligament (ACL) and both menisci were transected, was used on skeletally mature Flemish Giant rabbits. Gross morphological assessments, elastic moduli, and glycosaminoglycan (GAG) coverage of the menisci were determined to quantify the amount of tissue damage 12 weeks post injury. This study is one of the first to monitor meniscal changes after inducing combined meniscal and ACL transections. A decrease in elastic moduli as well as a decrease in GAG coverage was seen. PMID:24749144

Integration of potential-field and digital geologic data for two North American geoscience transects

USGS Publications Warehouse

Phillips, J.D.

1990-01-01

Two North American contributions to the Global Geoscience Transects Program, the Quebec-Maine-Gulf of Maine transect and the Great Lakes portion of the United States-Canadian Border transect, are among the first to produce digital geology in a form that can be combined with gridded gravity and aeromagnetic data. Maps of shaded relief and color-composite bandpass-filtered potential-field data combined with overlays of digitized geologic contacts and faults reveal significant new geologic information, including the relative thickness of plutons, the structure of poorly exposed or concealed magnetic units, and possible evidence for mineralized ground. -from Author

Seismic structure from multi-channel seismic reflection and wide-angle data of Transect 0E in the Southern Gulf of California

NASA Astrophysics Data System (ADS)

Paramo, P.; Holbrook, W.; Brown, H.; Lizarralde, D.; Fletcher, J.; Umhoefer, P.; Kent, G.; Harding, A.; Gonzalez, A.; Axen, G.

2005-12-01

We present a velocity model from wide-angle data along with coincident prestack depth migration sections from seismic reflection data collected in the southern Gulf of California. Transect 0E runs NE to SW from the hills of Sierra Madre in mainland Mexico near Mazatlan to approximately 115 km into Gulf of California waters. Wide-angle data were recorded by 9 ocean bottom seismometers, deployed by the R/V New Horizon and 10 Reftek seismometers located along onshore extension of the transect. The average spacing for the OBS and Refteks is ~12 km and shots were fired from the R/V Maurice Ewing at 150 m intervals. Transect 0E crosses what it is believed to be extended continental crust and lies in the initial direction of extension characteristic of the proto-gulf. Preliminary results from the velocity model show upper crustal velocities of 6.1-6.3 km/s and lower crustal velocities of 6.7-7.0 km/s along the entire transect. Seismic velocities and crustal thicknesses observed along transect 0E are characteristic of non-volcanic margins.

Efficient subtle motion detection from high-speed video for sound recovery and vibration analysis using singular value decomposition-based approach

NASA Astrophysics Data System (ADS)

Zhang, Dashan; Guo, Jie; Jin, Yi; Zhu, Chang'an

2017-09-01

High-speed cameras provide full field measurement of structure motions and have been applied in nondestructive testing and noncontact structure monitoring. Recently, a phase-based method has been proposed to extract sound-induced vibrations from phase variations in videos, and this method provides insights into the study of remote sound surveillance and material analysis. An efficient singular value decomposition (SVD)-based approach is introduced to detect sound-induced subtle motions from pixel intensities in silent high-speed videos. A high-speed camera is initially applied to capture a video of the vibrating objects stimulated by sound fluctuations. Then, subimages collected from a small region on the captured video are reshaped into vectors and reconstructed to form a matrix. Orthonormal image bases (OIBs) are obtained from the SVD of the matrix; available vibration signal can then be obtained by projecting subsequent subimages onto specific OIBs. A simulation test is initiated to validate the effectiveness and efficiency of the proposed method. Two experiments are conducted to demonstrate the potential applications in sound recovery and material analysis. Results show that the proposed method efficiently detects subtle motions from the video.

Still-to-video face recognition in unconstrained environments

NASA Astrophysics Data System (ADS)

Wang, Haoyu; Liu, Changsong; Ding, Xiaoqing

2015-02-01

Face images from video sequences captured in unconstrained environments usually contain several kinds of variations, e.g. pose, facial expression, illumination, image resolution and occlusion. Motion blur and compression artifacts also deteriorate recognition performance. Besides, in various practical systems such as law enforcement, video surveillance and e-passport identification, only a single still image per person is enrolled as the gallery set. Many existing methods may fail to work due to variations in face appearances and the limit of available gallery samples. In this paper, we propose a novel approach for still-to-video face recognition in unconstrained environments. By assuming that faces from still images and video frames share the same identity space, a regularized least squares regression method is utilized to tackle the multi-modality problem. Regularization terms based on heuristic assumptions are enrolled to avoid overfitting. In order to deal with the single image per person problem, we exploit face variations learned from training sets to synthesize virtual samples for gallery samples. We adopt a learning algorithm combining both affine/convex hull-based approach and regularizations to match image sets. Experimental results on a real-world dataset consisting of unconstrained video sequences demonstrate that our method outperforms the state-of-the-art methods impressively.

Video quality assessment method motivated by human visual perception

NASA Astrophysics Data System (ADS)

He, Meiling; Jiang, Gangyi; Yu, Mei; Song, Yang; Peng, Zongju; Shao, Feng

2016-11-01

Research on video quality assessment (VQA) plays a crucial role in improving the efficiency of video coding and the performance of video processing. It is well acknowledged that the motion energy model generates motion energy responses in a middle temporal area by simulating the receptive field of neurons in V1 for the motion perception of the human visual system. Motivated by the biological evidence for the visual motion perception, a VQA method is proposed in this paper, which comprises the motion perception quality index and the spatial index. To be more specific, the motion energy model is applied to evaluate the temporal distortion severity of each frequency component generated from the difference of Gaussian filter bank, which produces the motion perception quality index, and the gradient similarity measure is used to evaluate the spatial distortion of the video sequence to get the spatial quality index. The experimental results of the LIVE, CSIQ, and IVP video databases demonstrate that the random forests regression technique trained by the generated quality indices is highly correspondent to human visual perception and has many significant improvements than comparable well-performing methods. The proposed method has higher consistency with subjective perception and higher generalization capability.

Video redaction: a survey and comparison of enabling technologies

NASA Astrophysics Data System (ADS)

Sah, Shagan; Shringi, Ameya; Ptucha, Raymond; Burry, Aaron; Loce, Robert

2017-09-01

With the prevalence of video recordings from smart phones, dash cams, body cams, and conventional surveillance cameras, privacy protection has become a major concern, especially in light of legislation such as the Freedom of Information Act. Video redaction is used to obfuscate sensitive and personally identifiable information. Today's typical workflow involves simple detection, tracking, and manual intervention. Automated methods rely on accurate detection mechanisms being paired with robust tracking methods across the video sequence to ensure the redaction of all sensitive information while minimizing spurious obfuscations. Recent studies have explored the use of convolution neural networks and recurrent neural networks for object detection and tracking. The present paper reviews the redaction problem and compares a few state-of-the-art detection, tracking, and obfuscation methods as they relate to redaction. The comparison introduces an evaluation metric that is specific to video redaction performance. The metric can be evaluated in a manner that allows balancing the penalty for false negatives and false positives according to the needs of particular application, thereby assisting in the selection of component methods and their associated hyperparameters such that the redacted video has fewer frames that require manual review.

Sexuality Education in Video Games: Recommendations for the Use of Video Games to Teach Human Sexuality Issues

ERIC Educational Resources Information Center

Gross, M. Scott

2005-01-01

This article provides a review of some of the currently available literature surrounding the academic study of video games. Many of these theoretical methods have been used to study film and television and are discussed here in order to frame the need for further examination of video games. Suggestions for the use of video games in the classroom…

An intelligent crowdsourcing system for forensic analysis of surveillance video

NASA Astrophysics Data System (ADS)

Tahboub, Khalid; Gadgil, Neeraj; Ribera, Javier; Delgado, Blanca; Delp, Edward J.

2015-03-01

Video surveillance systems are of a great value for public safety. With an exponential increase in the number of cameras, videos obtained from surveillance systems are often archived for forensic purposes. Many automatic methods have been proposed to do video analytics such as anomaly detection and human activity recognition. However, such methods face significant challenges due to object occlusions, shadows and scene illumination changes. In recent years, crowdsourcing has become an effective tool that utilizes human intelligence to perform tasks that are challenging for machines. In this paper, we present an intelligent crowdsourcing system for forensic analysis of surveillance video that includes the video recorded as a part of search and rescue missions and large-scale investigation tasks. We describe a method to enhance crowdsourcing by incorporating human detection, re-identification and tracking. At the core of our system, we use a hierarchal pyramid model to distinguish the crowd members based on their ability, experience and performance record. Our proposed system operates in an autonomous fashion and produces a final output of the crowdsourcing analysis consisting of a set of video segments detailing the events of interest as one storyline.

Live lecture versus video podcast in undergraduate medical education: A randomised controlled trial

PubMed Central

2010-01-01

Background Information technology is finding an increasing role in the training of medical students. We compared information recall and student experience and preference after live lectures and video podcasts in undergraduate medical education. Methods We performed a crossover randomised controlled trial. 100 students were randomised to live lecture or video podcast for one clinical topic. Live lectures were given by the same instructor as the narrator of the video podcasts. The video podcasts comprised Powerpoint™ slides narrated using the same script as the lecture. They were then switched to the other group for a second clinical topic. Knowledge was assessed using multiple choice questions and qualitative information was collected using a questionnaire. Results No significant difference was found on multiple choice questioning immediately after the session. The subjects enjoyed the convenience of the video podcast and the ability to stop, review and repeat it, but found it less engaging as a teaching method. They expressed a clear preference for the live lecture format. Conclusions We suggest that video podcasts are not ready to replace traditional teaching methods, but may have an important role in reinforcing learning and aiding revision. PMID:20932302

Texture-adaptive hyperspectral video acquisition system with a spatial light modulator

NASA Astrophysics Data System (ADS)

Fang, Xiaojing; Feng, Jiao; Wang, Yongjin

2014-10-01

We present a new hybrid camera system based on spatial light modulator (SLM) to capture texture-adaptive high-resolution hyperspectral video. The hybrid camera system records a hyperspectral video with low spatial resolution using a gray camera and a high-spatial resolution video using a RGB camera. The hyperspectral video is subsampled by the SLM. The subsampled points can be adaptively selected according to the texture characteristic of the scene by combining with digital imaging analysis and computational processing. In this paper, we propose an adaptive sampling method utilizing texture segmentation and wavelet transform (WT). We also demonstrate the effectiveness of the sampled pattern on the SLM with the proposed method.

Pornographic information of Internet views detection method based on the connected areas

NASA Astrophysics Data System (ADS)

Wang, Huibai; Fan, Ajie

2017-01-01

Nowadays online porn video broadcasting and downloading is very popular. In view of the widespread phenomenon of Internet pornography, this paper proposed a new method of pornographic video detection based on connected areas. Firstly, decode the video into a serious of static images and detect skin color on the extracted key frames. If the area of skin color reaches a certain threshold, use the AdaBoost algorithm to detect the human face. Judge the connectivity of the human face and the large area of skin color to determine whether detect the sensitive area finally. The experimental results show that the method can effectively remove the non-pornographic videos contain human who wear less. This method can improve the efficiency and reduce the workload of detection.

Background-Modeling-Based Adaptive Prediction for Surveillance Video Coding.

PubMed

Zhang, Xianguo; Huang, Tiejun; Tian, Yonghong; Gao, Wen

2014-02-01

The exponential growth of surveillance videos presents an unprecedented challenge for high-efficiency surveillance video coding technology. Compared with the existing coding standards that were basically developed for generic videos, surveillance video coding should be designed to make the best use of the special characteristics of surveillance videos (e.g., relative static background). To do so, this paper first conducts two analyses on how to improve the background and foreground prediction efficiencies in surveillance video coding. Following the analysis results, we propose a background-modeling-based adaptive prediction (BMAP) method. In this method, all blocks to be encoded are firstly classified into three categories. Then, according to the category of each block, two novel inter predictions are selectively utilized, namely, the background reference prediction (BRP) that uses the background modeled from the original input frames as the long-term reference and the background difference prediction (BDP) that predicts the current data in the background difference domain. For background blocks, the BRP can effectively improve the prediction efficiency using the higher quality background as the reference; whereas for foreground-background-hybrid blocks, the BDP can provide a better reference after subtracting its background pixels. Experimental results show that the BMAP can achieve at least twice the compression ratio on surveillance videos as AVC (MPEG-4 Advanced Video Coding) high profile, yet with a slightly additional encoding complexity. Moreover, for the foreground coding performance, which is crucial to the subjective quality of moving objects in surveillance videos, BMAP also obtains remarkable gains over several state-of-the-art methods.

Spatial and temporal variability of soil hydraulic properties of topsoil affected by soil erosion

NASA Astrophysics Data System (ADS)

Nikodem, Antonin; Kodesova, Radka; Jaksik, Ondrej; Jirku, Veronika; Klement, Ales; Fer, Miroslav

2014-05-01

This study is focused on the comparison of soil hydraulic properties of topsoil that is affected by erosion processes. In order to include variable morphological and soil properties along the slope three sites - Brumovice, Vidim and Sedlčany were selected. Two transects (A, B) and five sampling sites along each one were chosen. Soil samples were taken in Brumovice after the tillage and sowing of winter wheat in October 2010 and after the wheat harvest in August 2011. At locality Vidim and Sedlčany samples were collected in May and August 2012. Soil hydraulic properties were studied in the laboratory on the undisturbed 100-cm3 soil samples placed in Tempe cells using the multi-step outflow test. Soil water retention data points were obtained by calculating water balance in the soil sample at each pressure head step of the experiment. The single-porosity model in HYDRUS-1D was applied to analyze the multi-step outflow and to obtain the parameters of soil hydraulic properties using the numerical inversion. The saturated hydraulic conductivities (Ks) and unsaturated hydraulic conductivities (Kw) for the pressure head of -2 cm of topsoil were also measured after the harvest using Guelph permeameter and Minidisk tensiometer, respectively. In general soil water retention curves measured before and after vegetation period apparently differed, which indicated soil material consolidation and soil-porous system rearrangement. Soil water retention curves obtained on the soil samples and hydraulic conductivities measured in the field reflected the position at the elevation transect and the effect of erosion/accumulation processes on soil structure and consequently on the soil hydraulic properties. The highest Ks values in Brumovice were obtained at the steepest parts of the elevation transects, that have been the most eroded. The Ks values at the bottom parts decreased due to the sedimentation of eroded soil particles. The change of the Kw values along transects didn't show similar trends. However, the variability of values within both transects was low. Higher values were obtained in transect B, where the soil was more affected by erosion. The highest values of Ks as well as the value of Kw were also obtained in the steepest part of transect A in Vidim. This trend was not observed in transect B. The results corresponded with measured retention curves. Two different trends were shown in Sedlčany. While the highest values of Ks and Kw were found in the upper part of transect A, in the case of transect B the highest values were measured at the bottom of transect. Differences observed at both localities were caused by the different terrain attributes of both transects and extent of soil erosion. Acknowledgement: Authors acknowledge the financial support of the Ministry of Agriculture of the Czech Republic (QJ1230319).

Fast Video Encryption Using the H.264 Error Propagation Property for Smart Mobile Devices

PubMed Central

Chung, Yongwha; Lee, Sungju; Jeon, Taewoong; Park, Daihee

2015-01-01

In transmitting video data securely over Video Sensor Networks (VSNs), since mobile handheld devices have limited resources in terms of processor clock speed and battery size, it is necessary to develop an efficient method to encrypt video data to meet the increasing demand for secure connections. Selective encryption methods can reduce the amount of computation needed while satisfying high-level security requirements. This is achieved by selecting an important part of the video data and encrypting it. In this paper, to ensure format compliance and security, we propose a special encryption method for H.264, which encrypts only the DC/ACs of I-macroblocks and the motion vectors of P-macroblocks. In particular, the proposed new selective encryption method exploits the error propagation property in an H.264 decoder and improves the collective performance by analyzing the tradeoff between the visual security level and the processing speed compared to typical selective encryption methods (i.e., I-frame, P-frame encryption, and combined I-/P-frame encryption). Experimental results show that the proposed method can significantly reduce the encryption workload without any significant degradation of visual security. PMID:25850068

Methods for the quantification of coarse woody debris and an examination of its spatial patterning: A study from the Tenderfoot Creek Experimental Forest, MT

Treesearch

Paul B. Alaback; Duncan C. Lutes

1997-01-01

Methods for the quantification of coarse woody debris volume and the description of spatial patterning were studied in the Tenderfoot Creek Experimental Forest, Montana. The line transect method was found to be an accurate, unbiased estimator of down debris volume (> 10cm diameter) on 1/4 hectare fixed-area plots, when perpendicular lines were used. The Fischer...

Optimizing Sampling Efficiency for Biomass Estimation Across NEON Domains

NASA Astrophysics Data System (ADS)

Abercrombie, H. H.; Meier, C. L.; Spencer, J. J.

2013-12-01

Over the course of 30 years, the National Ecological Observatory Network (NEON) will measure plant biomass and productivity across the U.S. to enable an understanding of terrestrial carbon cycle responses to ecosystem change drivers. Over the next several years, prior to operational sampling at a site, NEON will complete construction and characterization phases during which a limited amount of sampling will be done at each site to inform sampling designs, and guide standardization of data collection across all sites. Sampling biomass in 60+ sites distributed among 20 different eco-climatic domains poses major logistical and budgetary challenges. Traditional biomass sampling methods such as clip harvesting and direct measurements of Leaf Area Index (LAI) involve collecting and processing plant samples, and are time and labor intensive. Possible alternatives include using indirect sampling methods for estimating LAI such as digital hemispherical photography (DHP) or using a LI-COR 2200 Plant Canopy Analyzer. These LAI estimations can then be used as a proxy for biomass. The biomass estimates calculated can then inform the clip harvest sampling design during NEON operations, optimizing both sample size and number so that standardized uncertainty limits can be achieved with a minimum amount of sampling effort. In 2011, LAI and clip harvest data were collected from co-located sampling points at the Central Plains Experimental Range located in northern Colorado, a short grass steppe ecosystem that is the NEON Domain 10 core site. LAI was measured with a LI-COR 2200 Plant Canopy Analyzer. The layout of the sampling design included four, 300 meter transects, with clip harvests plots spaced every 50m, and LAI sub-transects spaced every 10m. LAI was measured at four points along 6m sub-transects running perpendicular to the 300m transect. Clip harvest plots were co-located 4m from corresponding LAI transects, and had dimensions of 0.1m by 2m. We conducted regression analyses with LAI and clip harvest data to determine whether LAI can be used as a suitable proxy for aboveground standing biomass. We also compared optimal sample sizes derived from LAI data, and clip-harvest data from two different size clip harvest areas (0.1m by 1m vs. 0.1m by 2m). Sample sizes were calculated in order to estimate the mean to within a standardized level of uncertainty that will be used to guide sampling effort across all vegetation types (i.e. estimated within × 10% with 95% confidence). Finally, we employed a Semivariogram approach to determine optimal sample size and spacing.

Research and development of a new RF-assisted device for bloodless rapid transection of the liver: Computational modeling and in vivo experiments

PubMed Central

Burdío, Fernando; Berjano, Enrique J; Navarro, Ana; Burdío, José M; Grande, Luis; Gonzalez, Ana; Cruz, Ignacio; Güemes, Antonio; Sousa, Ramón; Subirá, Jorge; Castiella, Tomás; Poves, Ignasi; Lequerica, Juan L

2009-01-01

Background Efficient and safe transection of biological tissue in liver surgery is strongly dependent on the ability to address both parenchymal division and hemostasis simultaneously. In addition to the conventional clamp crushing or finger fracture methods other techniques based on radiofrequency (RF) currents have been extensively employed to reduce intraoperative blood loss. In this paper we present our broad research plan for a new RF-assisted device for bloodless, rapid resection of the liver. Methods Our research plan includes computer modeling and in vivo studies. Computer modeling was based on the Finite Element Method (FEM) and allowed us to estimate the distribution of electrical power deposited in the tissue, along with assessing the effect of the characteristics of the device on the temperature profiles. Studies based on in vivo pig liver models provided a comparison of the performance of the new device with other techniques (saline-linked technology) currently employed in clinical practice. Finally, the plan includes a pilot clinical trial, in which both the new device and the accessory equipment are seen to comply with all safety requirements. Results The FEM results showed a high electrical gradient around the tip of the blade, responsible for the maximal increase of temperature at that point, where temperature reached 100°C in only 3.85 s. Other hot points with lower temperatures were located at the proximal edge of the device. Additional simulations with an electrically insulated blade produced more uniform and larger lesions (assessed as the 55°C isotherm) than the electrically conducting blade. The in vivo study, in turn, showed greater transection speed (3 ± 0 and 3 ± 1 cm2/min for the new device in the open and laparoscopic approaches respectively) and also lower blood loss (70 ± 74 and 26 ± 34 mL) during transection of the liver, as compared to saline-linked technology (2 ± 1 cm2/min with P = 0.002, and 527 ± 273 mL with P = 0.001). Conclusion A new RF-assisted device for bloodless, rapid liver resection was designed, built and tested. The results demonstrate the potential advantages of this device over others currently employed. PMID:19296852

Development and Validation of a Video Measure for Assessing Women’s Risk Perception for Alcohol-Related Sexual Assault

PubMed Central

Parks, Kathleen A.; Levonyan-Radloff, Kristine; Dearing, Ronda L.; Hequembourg, Amy; Testa, Maria

2016-01-01

Objective Using an iterative process, a series of three video scenarios were developed for use as a standardized measure for assessing women’s perception of risks for alcohol-related sexual assault (SA). The videos included ambiguous and clear behavioral and environmental risk cues. Method Focus group discussions with young, female heavy drinkers (N = 42) were used to develop three videos at different risk levels (low, moderate, and high) in Study 1. Realism, reliability, and validity of the videos were assessed using multiple methods in Studies 2 and 3. One hundred-four women were used to compare differences in risk perception across the video risk level in Study 2. In Study 3 (N = 60), we assessed women’s perceptions of the low and high risk videos under conditions of no alcohol and alcohol. Results The realism and reliability of the videos were good. Women who viewed the low risk video compared to women who viewed the moderate and high risk videos perceived less risk for SA. We found an interaction between alcohol and risk perception such that, women in the alcohol condition were less likely to perceive risk when watching the high risk video. Conclusions As the video risk level increased, women’s perception of risk increased. These findings provide convergent evidence for the validity of the video measure. Given the limited number of standardized scenarios for assessing risk perception for sexual assault, our findings suggest that these videos may provide a needed standardized measure. PMID:27747131

Spatiotemporal video deinterlacing using control grid interpolation

NASA Astrophysics Data System (ADS)

Venkatesan, Ragav; Zwart, Christine M.; Frakes, David H.; Li, Baoxin

2015-03-01

With the advent of progressive format display and broadcast technologies, video deinterlacing has become an important video-processing technique. Numerous approaches exist in the literature to accomplish deinterlacing. While most earlier methods were simple linear filtering-based approaches, the emergence of faster computing technologies and even dedicated video-processing hardware in display units has allowed higher quality but also more computationally intense deinterlacing algorithms to become practical. Most modern approaches analyze motion and content in video to select different deinterlacing methods for various spatiotemporal regions. We introduce a family of deinterlacers that employs spectral residue to choose between and weight control grid interpolation based spatial and temporal deinterlacing methods. The proposed approaches perform better than the prior state-of-the-art based on peak signal-to-noise ratio, other visual quality metrics, and simple perception-based subjective evaluations conducted by human viewers. We further study the advantages of using soft and hard decision thresholds on the visual performance.

Compressive Video Recovery Using Block Match Multi-Frame Motion Estimation Based on Single Pixel Cameras

PubMed Central

Bi, Sheng; Zeng, Xiao; Tang, Xin; Qin, Shujia; Lai, King Wai Chiu

2016-01-01

Compressive sensing (CS) theory has opened up new paths for the development of signal processing applications. Based on this theory, a novel single pixel camera architecture has been introduced to overcome the current limitations and challenges of traditional focal plane arrays. However, video quality based on this method is limited by existing acquisition and recovery methods, and the method also suffers from being time-consuming. In this paper, a multi-frame motion estimation algorithm is proposed in CS video to enhance the video quality. The proposed algorithm uses multiple frames to implement motion estimation. Experimental results show that using multi-frame motion estimation can improve the quality of recovered videos. To further reduce the motion estimation time, a block match algorithm is used to process motion estimation. Experiments demonstrate that using the block match algorithm can reduce motion estimation time by 30%. PMID:26950127

Is Video-Based Education an Effective Method in Surgical Education? A Systematic Review.

PubMed

Ahmet, Akgul; Gamze, Kus; Rustem, Mustafaoglu; Sezen, Karaborklu Argut

2018-02-12

Visual signs draw more attention during the learning process. Video is one of the most effective tool including a lot of visual cues. This systematic review set out to explore the influence of video in surgical education. We reviewed the current evidence for the video-based surgical education methods, discuss the advantages and disadvantages on the teaching of technical and nontechnical surgical skills. This systematic review was conducted according to the guidelines defined in the preferred reporting items for systematic reviews and meta-analyses statement. The electronic databases: the Cochrane Library, Medline (PubMED), and ProQuest were searched from their inception to the 30 January 2016. The Medical Subject Headings (MeSH) terms and keywords used were "video," "education," and "surgery." We analyzed all full-texts, randomised and nonrandomised clinical trials and observational studies including video-based education methods about any surgery. "Education" means a medical resident's or student's training and teaching process; not patients' education. We did not impose restrictions about language or publication date. A total of nine articles which met inclusion criteria were included. These trials enrolled 507 participants and the total number of participants per trial ranged from 10 to 172. Nearly all of the studies reviewed report significant knowledge gain from video-based education techniques. The findings of this systematic review provide fair to good quality studies to demonstrate significant gains in knowledge compared with traditional teaching. Additional video to simulator exercise or 3D animations has beneficial effects on training time, learning duration, acquisition of surgical skills, and trainee's satisfaction. Video-based education has potential for use in surgical education as trainees face significant barriers in their practice. This method is effective according to the recent literature. Video should be used in addition to standard techniques in the surgical education. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Guided transect sampling - a new design combining prior information and field surveying

Treesearch

Anna Ringvall; Goran Stahl; Tomas Lamas

2000-01-01

Guided transect sampling is a two-stage sampling design in which prior information is used to guide the field survey in the second stage. In the first stage, broad strips are randomly selected and divided into grid-cells. For each cell a covariate value is estimated from remote sensing data, for example. The covariate is the basis for subsampling of a transect through...

Enhancing fish Underwater Visual Census to move forward assessment of fish assemblages: An application in three Mediterranean Marine Protected Areas

PubMed Central

Thiriet, Pierre; Di Franco, Antonio; Francour, Patrice

2017-01-01

Monitoring fish assemblages is needed to assess whether Marine Protected Areas (MPAs) are meeting their conservation and fisheries management goals, as it allows one to track the progress of recovery of exploited species and associated communities. Underwater Visual Census techniques (UVC) are used to monitor fish assemblages in MPAs. UVCs should be adapted to fish abundance, body-size and behaviour, which can strongly affect fish detectability. In Mediterranean subtidal habitats, however, UVC strip transects of one surface area (25x5 m2) are commonly used to survey the whole fish assemblage, from large shy fish to small crypto-benthic fish. Most high trophic level predators (HTLPs) are large shy fish which rarely swim close to divers and, consequently, their abundance may be under-estimated with commonly used transects. Here, we propose an improvement to traditional transect surveys to better account for differences in behaviour among and within species. First, we compared the effectiveness of combining two transect surface areas (large: 35x20 m2; medium: 25x5 m2) in quantifying large, shy fish within and outside Mediterranean MPAs. We identified species-specific body-size thresholds defining a smaller and a larger size class better sampled by medium and large transects respectively. Combining large and medium transects provided more accurate biomass and species richness estimates for large, shy species than using medium transects alone. We thus combined the new approach with two other transect surface areas commonly used to survey crypto-benthic (10x1 m2) and necto-benthic (25x5 m2) species in order to assess how effectively MPAs protection the whole fish assemblage. We verified that MPAs offer significant protection for HTLPs, their response in terms of biomass and density increase in MPAs was always higher in magnitude than other functional groups. Inside MPAs, the contribution of HTLP reached >25% of total fish biomass, against < 2% outside MPAs. Surveys with multiple transect surface areas allow for a more realistic assessment of the structure of the whole fish assemblage and better assessment of potential recovery of HTLPs within reserves of HTLP. PMID:28594836

Enhancing fish Underwater Visual Census to move forward assessment of fish assemblages: An application in three Mediterranean Marine Protected Areas.

PubMed

Prato, Giulia; Thiriet, Pierre; Di Franco, Antonio; Francour, Patrice

2017-01-01

Monitoring fish assemblages is needed to assess whether Marine Protected Areas (MPAs) are meeting their conservation and fisheries management goals, as it allows one to track the progress of recovery of exploited species and associated communities. Underwater Visual Census techniques (UVC) are used to monitor fish assemblages in MPAs. UVCs should be adapted to fish abundance, body-size and behaviour, which can strongly affect fish detectability. In Mediterranean subtidal habitats, however, UVC strip transects of one surface area (25x5 m2) are commonly used to survey the whole fish assemblage, from large shy fish to small crypto-benthic fish. Most high trophic level predators (HTLPs) are large shy fish which rarely swim close to divers and, consequently, their abundance may be under-estimated with commonly used transects. Here, we propose an improvement to traditional transect surveys to better account for differences in behaviour among and within species. First, we compared the effectiveness of combining two transect surface areas (large: 35x20 m2; medium: 25x5 m2) in quantifying large, shy fish within and outside Mediterranean MPAs. We identified species-specific body-size thresholds defining a smaller and a larger size class better sampled by medium and large transects respectively. Combining large and medium transects provided more accurate biomass and species richness estimates for large, shy species than using medium transects alone. We thus combined the new approach with two other transect surface areas commonly used to survey crypto-benthic (10x1 m2) and necto-benthic (25x5 m2) species in order to assess how effectively MPAs protection the whole fish assemblage. We verified that MPAs offer significant protection for HTLPs, their response in terms of biomass and density increase in MPAs was always higher in magnitude than other functional groups. Inside MPAs, the contribution of HTLP reached >25% of total fish biomass, against < 2% outside MPAs. Surveys with multiple transect surface areas allow for a more realistic assessment of the structure of the whole fish assemblage and better assessment of potential recovery of HTLPs within reserves of HTLP.

Motivation and Learning Engagement through Playing Math Video Games

ERIC Educational Resources Information Center

Barreto, Daisyane; Vasconcelos, Lucas; Orey, Michael

2017-01-01

Purpose: With video games being a source of leisure and learning, educators and researchers alike are interested in understanding children's motivation for playing video games as a way to learn. This study explores student motivation and engagement levels in playing two math video games in the game "Club Penguin." Method: This is a…

The Technological Barriers of Using Video Modeling in the Classroom

ERIC Educational Resources Information Center

Marino, Desha; Myck-Wayne, Janice

2015-01-01

The purpose of this investigation is to identify the technological barriers teachers encounter when attempting to implement video modeling in the classroom. Video modeling is an emerging evidence-based intervention method used with individuals with autism. Research has shown the positive effects video modeling can have on its recipients. Educators…

Probabilistic Methods for Image Generation and Encoding.

DTIC Science & Technology

1993-10-15

video and graphics lab at Georgia Tech, linking together Silicon Graphics workstations, a laser video recorder, a Betacam video recorder, scanner...computer laboratory at Georgia Tech, based on two Silicon Graphics Personal Iris workstations, a SONY laser video recorder, a SONY Betacam SP video...laser disk in component RGB form, with variable speed playback. From the laser recorder the images can be dubbed to the Betacam or the VHS recorder in

Evaluation of automatic video summarization systems

NASA Astrophysics Data System (ADS)

Taskiran, Cuneyt M.

2006-01-01

Compact representations of video, or video summaries, data greatly enhances efficient video browsing. However, rigorous evaluation of video summaries generated by automatic summarization systems is a complicated process. In this paper we examine the summary evaluation problem. Text summarization is the oldest and most successful summarization domain. We show some parallels between these to domains and introduce methods and terminology. Finally, we present results for a comprehensive evaluation summary that we have performed.

Chemistry of cometary meteoroids from video-tape records of meteor spectra

NASA Technical Reports Server (NTRS)

Millman, P. M.

1982-01-01

The chemistry of the cometary meteoroids was studied by closed circuit television observing systems. Vidicon cameras produce basic data on standard video tape and enable the recording of the spectra of faint shower meteors, consequently the chemical study is extended to smaller particles and we have a larger data bank than is available from the more conventional method of recording meteor spectra by photography. The two main problems in using video tape meteor spectrum records are: (1) the video tape recording has a much lower resolution than the photographic technique; (2) video tape is relatively new type of data storage in astronomy and the methods of quantitative photometry have not yet been fully developed in the various fields where video tape is used. The use of the most detailed photographic meteor spectra to calibrate the video tape records and to make positive identification of the more prominent chemical elements appearing in the spectra may solve the low resolution problem. Progress in the development of standard photometric techniques for the analysis of video tape records of meteor spectra is reported.

Secured web-based video repository for multicenter studies

PubMed Central

Yan, Ling; Hicks, Matt; Winslow, Korey; Comella, Cynthia; Ludlow, Christy; Jinnah, H. A; Rosen, Ami R; Wright, Laura; Galpern, Wendy R; Perlmutter, Joel S

2015-01-01

Background We developed a novel secured web-based dystonia video repository for the Dystonia Coalition, part of the Rare Disease Clinical Research network funded by the Office of Rare Diseases Research and the National Institute of Neurological Disorders and Stroke. A critical component of phenotypic data collection for all projects of the Dystonia Coalition includes a standardized video of each participant. We now describe our method for collecting, serving and securing these videos that is widely applicable to other studies. Methods Each recruiting site uploads standardized videos to a centralized secured server for processing to permit website posting. The streaming technology used to view the videos from the website does not allow downloading of video files. With appropriate institutional review board approval and agreement with the hosting institution, users can search and view selected videos on the website using customizable, permissions-based access that maintains security yet facilitates research and quality control. Results This approach provides a convenient platform for researchers across institutions to evaluate and analyze shared video data. We have applied this methodology for quality control, confirmation of diagnoses, validation of rating scales, and implementation of new research projects. Conclusions We believe our system can be a model for similar projects that require access to common video resources. PMID:25630890

Rolling and scrolling: The portrayal of marijuana cigars (blunts) on YouTube

PubMed Central

Montgomery, LaTrice; Yockey, Andrew

2018-01-01

Background Blunts are partially or fully hollowed-out cigars or cigarillos that are filled with marijuana. Despite the high prevalence of blunt use, very few studies assess this specific method of cannabis administration. YouTube, a popular video-sharing website, has the potential to provide insights into blunt use. Methods The purpose of this study was to examine the content of YouTube videos that discuss blunts. A sample of 41 videos was coded for content. Results The 41 videos had a total of 27,579,636 views. Most of the individuals in the videos were male (85%) and many appeared to be White (80%) and under the age of 25 (46%). Only 34% of the videos had an age restriction. The majority of messages in the videos promoted blunt use (93%) and showed at least one person rolling (76%) and/or smoking (66%) a blunt. The videos mainly consisted of introductions to blunt use (76%) and tips and personal experiences with blunt use (73%). Conclusions YouTube videos on blunt use are readily available and primarily promote the use of blunts. Future research should continue to monitor YouTube content and develop videos on social media platforms that inform consumers of the health effects associated with blunt use. PMID:29887756

User interface using a 3D model for video surveillance

NASA Astrophysics Data System (ADS)

Hata, Toshihiko; Boh, Satoru; Tsukada, Akihiro; Ozaki, Minoru

1998-02-01

These days fewer people, who must carry out their tasks quickly and precisely, are required in industrial surveillance and monitoring applications such as plant control or building security. Utilizing multimedia technology is a good approach to meet this need, and we previously developed Media Controller, which is designed for the applications and provides realtime recording and retrieval of digital video data in a distributed environment. In this paper, we propose a user interface for such a distributed video surveillance system in which 3D models of buildings and facilities are connected to the surveillance video. A novel method of synchronizing camera field data with each frame of a video stream is considered. This method records and reads the camera field data similarity to the video data and transmits it synchronously with the video stream. This enables the user interface to have such useful functions as comprehending the camera field immediately and providing clues when visibility is poor, for not only live video but also playback video. We have also implemented and evaluated the display function which makes surveillance video and 3D model work together using Media Controller with Java and Virtual Reality Modeling Language employed for multi-purpose and intranet use of 3D model.

Detection of inter-frame forgeries in digital videos.

PubMed

K, Sitara; Mehtre, B M

2018-05-26

Videos are acceptable as evidence in the court of law, provided its authenticity and integrity are scientifically validated. Videos recorded by surveillance systems are susceptible to malicious alterations of visual content by perpetrators locally or remotely. Such malicious alterations of video contents (called video forgeries) are categorized into inter-frame and intra-frame forgeries. In this paper, we propose inter-frame forgery detection techniques using tamper traces from spatio-temporal and compressed domains. Pristine videos containing frames that are recorded during sudden camera zooming event, may get wrongly classified as tampered videos leading to an increase in false positives. To address this issue, we propose a method for zooming detection and it is incorporated in video tampering detection. Frame shuffling detection, which was not explored so far is also addressed in our work. Our method is capable of differentiating various inter-frame tamper events and its localization in the temporal domain. The proposed system is tested on 23,586 videos of which 2346 are pristine and rest of them are candidates of inter-frame forged videos. Experimental results show that we have successfully detected frame shuffling with encouraging accuracy rates. We have achieved improved accuracy on forgery detection in frame insertion, frame deletion and frame duplication. Copyright © 2018. Published by Elsevier B.V.

Video Surveillance Captures Student Hand Hygiene Behavior, Reactivity to Observation, and Peer Influence in Kenyan Primary Schools

PubMed Central

Pickering, Amy J.; Blum, Annalise G.; Breiman, Robert F.; Ram, Pavani K.; Davis, Jennifer

2014-01-01

Background In-person structured observation is considered the best approach for measuring hand hygiene behavior, yet is expensive, time consuming, and may alter behavior. Video surveillance could be a useful tool for objectively monitoring hand hygiene behavior if validated against current methods. Methods Student hand cleaning behavior was monitored with video surveillance and in-person structured observation, both simultaneously and separately, at four primary schools in urban Kenya over a study period of 8 weeks. Findings Video surveillance and in-person observation captured similar rates of hand cleaning (absolute difference <5%, p = 0.74). Video surveillance documented higher hand cleaning rates (71%) when at least one other person was present at the hand cleaning station, compared to when a student was alone (48%; rate ratio  = 1.14 [95% CI 1.01–1.28]). Students increased hand cleaning rates during simultaneous video and in-person monitoring as compared to single-method monitoring, suggesting reactivity to each method of monitoring. This trend was documented at schools receiving a handwashing with soap intervention, but not at schools receiving a sanitizer intervention. Conclusion Video surveillance of hand hygiene behavior yields results comparable to in-person observation among schools in a resource-constrained setting. Video surveillance also has certain advantages over in-person observation, including rapid data processing and the capability to capture new behavioral insights. Peer influence can significantly improve student hand cleaning behavior and, when possible, should be exploited in the design and implementation of school hand hygiene programs. PMID:24676389

Feasibility of video codec algorithms for software-only playback

NASA Astrophysics Data System (ADS)

Rodriguez, Arturo A.; Morse, Ken

1994-05-01

Software-only video codecs can provide good playback performance in desktop computers with a 486 or 68040 CPU running at 33 MHz without special hardware assistance. Typically, playback of compressed video can be categorized into three tasks: the actual decoding of the video stream, color conversion, and the transfer of decoded video data from system RAM to video RAM. By current standards, good playback performance is the decoding and display of video streams of 320 by 240 (or larger) compressed frames at 15 (or greater) frames-per- second. Software-only video codecs have evolved by modifying and tailoring existing compression methodologies to suit video playback in desktop computers. In this paper we examine the characteristics used to evaluate software-only video codec algorithms, namely: image fidelity (i.e., image quality), bandwidth (i.e., compression) ease-of-decoding (i.e., playback performance), memory consumption, compression to decompression asymmetry, scalability, and delay. We discuss the tradeoffs among these variables and the compromises that can be made to achieve low numerical complexity for software-only playback. Frame- differencing approaches are described since software-only video codecs typically employ them to enhance playback performance. To complement other papers that appear in this session of the Proceedings, we review methods derived from binary pattern image coding since these methods are amenable for software-only playback. In particular, we introduce a novel approach called pixel distribution image coding.

A Video Method to Study Drosophila Sleep

PubMed Central

Zimmerman, John E.; Raizen, David M.; Maycock, Matthew H.; Maislin, Greg; Pack, Allan I.

2008-01-01

Study Objectives: To use video to determine the accuracy of the infrared beam-splitting method for measuring sleep in Drosophila and to determine the effect of time of day, sex, genotype, and age on sleep measurements. Design: A digital image analysis method based on frame subtraction principle was developed to distinguish a quiescent from a moving fly. Data obtained using this method were compared with data obtained using the Drosophila Activity Monitoring System (DAMS). The location of the fly was identified based on its centroid location in the subtracted images. Measurements and Results: The error associated with the identification of total sleep using DAMS ranged from 7% to 95% and depended on genotype, sex, age, and time of day. The degree of the total sleep error was dependent on genotype during the daytime (P < 0.001) and was dependent on age during both the daytime and the nighttime (P < 0.001 for both). The DAMS method overestimated sleep bout duration during both the day and night, and the degree of these errors was genotype dependent (P < 0.001). Brief movements that occur during sleep bouts can be accurately identified using video. Both video and DAMS detected a homeostatic response to sleep deprivation. Conclusions: Video digital analysis is more accurate than DAMS in fly sleep measurements. In particular, conclusions drawn from DAMS measurements regarding daytime sleep and sleep architecture should be made with caution. Video analysis also permits the assessment of fly position and brief movements during sleep. Citation: Zimmerman JE; Raizen DM; Maycock MH; Maislin G; Pack AI. A video method to study drosophila sleep. SLEEP 2008;31(11):1587–1598. PMID:19014079

Integrated bronchoscopic video tracking and 3D CT registration for virtual bronchoscopy

NASA Astrophysics Data System (ADS)

Higgins, William E.; Helferty, James P.; Padfield, Dirk R.

2003-05-01

Lung cancer assessment involves an initial evaluation of 3D CT image data followed by interventional bronchoscopy. The physician, with only a mental image inferred from the 3D CT data, must guide the bronchoscope through the bronchial tree to sites of interest. Unfortunately, this procedure depends heavily on the physician's ability to mentally reconstruct the 3D position of the bronchoscope within the airways. In order to assist physicians in performing biopsies of interest, we have developed a method that integrates live bronchoscopic video tracking and 3D CT registration. The proposed method is integrated into a system we have been devising for virtual-bronchoscopic analysis and guidance for lung-cancer assessment. Previously, the system relied on a method that only used registration of the live bronchoscopic video to corresponding virtual endoluminal views derived from the 3D CT data. This procedure only performs the registration at manually selected sites; it does not draw upon the motion information inherent in the bronchoscopic video. Further, the registration procedure is slow. The proposed method has the following advantages: (1) it tracks the 3D motion of the bronchoscope using the bronchoscopic video; (2) it uses the tracked 3D trajectory of the bronchoscope to assist in locating sites in the 3D CT "virtual world" to perform the registration. In addition, the method incorporates techniques to: (1) detect and exclude corrupted video frames (to help make the video tracking more robust); (2) accelerate the computation of the many 3D virtual endoluminal renderings (thus, speeding up the registration process). We have tested the integrated tracking-registration method on a human airway-tree phantom and on real human data.

Deblocking of mobile stereo video

NASA Astrophysics Data System (ADS)

Azzari, Lucio; Gotchev, Atanas; Egiazarian, Karen

2012-02-01

Most of candidate methods for compression of mobile stereo video apply block-transform based compression based on the H-264 standard with quantization of transform coefficients driven by quantization parameter (QP). The compression ratio and the resulting bit rate are directly determined by the QP level and high compression is achieved for the price of visually noticeable blocking artifacts. Previous studies on perceived quality of mobile stereo video have revealed that blocking artifacts are the most annoying and most influential in the acceptance/rejection of mobile stereo video and can even completely cancel the 3D effect and the corresponding quality added value. In this work, we address the problem of deblocking of mobile stereo video. We modify a powerful non-local transform-domain collaborative filtering method originally developed for denoising of images and video. The method employs grouping of similar block patches residing in spatial and temporal vicinity of a reference block in filtering them collaboratively in a suitable transform domain. We study the most suitable way of finding similar patches in both channels of stereo video and suggest a hybrid four-dimensional transform to process the collected synchronized (stereo) volumes of grouped blocks. The results benefit from the additional correlation available between the left and right channel of the stereo video. Furthermore, addition sharpening is applied through an embedded alpha-rooting in transform domain, which improve the visual appearance of the deblocked frames.

Field methods to measure surface displacement and strain with the Video Image Correlation method

NASA Technical Reports Server (NTRS)

Maddux, Gary A.; Horton, Charles M.; Mcneill, Stephen R.; Lansing, Matthew D.

1994-01-01

The objective of this project was to develop methods and application procedures to measure displacement and strain fields during the structural testing of aerospace components using paint speckle in conjunction with the Video Image Correlation (VIC) system.

The Effectiveness of Streaming Video on Medical Student Learning: A Case Study

PubMed Central

Bridge, Patrick D.; Jackson, Matt; Robinson, Leah

2009-01-01

Information technology helps meet today's medical students’ needs by providing multiple curriculum delivery methods. Video streaming is an e-learning technology that uses the Internet to deliver curriculum while giving the student control of the content's delivery. There have been few studies conducted on the effectiveness of streaming video in medical schools. A 5-year retrospective study was conducted using three groups of students (n = 1736) to determine if the availability of streaming video in Years 1–2 of the basic science curriculum affected overall Step 1 scores for first-time test-takers. The results demonstrated a positive effect on program outcomes as streaming video became more readily available to students. Based on these findings, streaming video technology seems to be a viable tool to complement in-class delivery methods, to accommodate the needs of medical students, and to provide options for meeting the challenges of delivering the undergraduate medical curriculum. Further studies need to be conducted to continue validating the effectiveness of streaming video technology. PMID:20165525

The effectiveness of streaming video on medical student learning: a case study.

PubMed

Bridge, Patrick D; Jackson, Matt; Robinson, Leah

2009-08-19

Information technology helps meet today's medical students' needs by providing multiple curriculum delivery methods. Video streaming is an e-learning technology that uses the Internet to deliver curriculum while giving the student control of the content's delivery. There have been few studies conducted on the effectiveness of streaming video in medical schools. A 5-year retrospective study was conducted using three groups of students (n = 1736) to determine if the availability of streaming video in Years 1-2 of the basic science curriculum affected overall Step 1 scores for first-time test-takers. The results demonstrated a positive effect on program outcomes as streaming video became more readily available to students. Based on these findings, streaming video technology seems to be a viable tool to complement in-class delivery methods, to accommodate the needs of medical students, and to provide options for meeting the challenges of delivering the undergraduate medical curriculum. Further studies need to be conducted to continue validating the effectiveness of streaming video technology.

Identification of Mobile Phone and Analysis of Original Version of Videos through a Delay Time Analysis of Sound Signals from Mobile Phone Videos.

PubMed

Hwang, Min Gu; Har, Dong Hwan

2017-11-01

This study designs a method of identifying the camera model used to take videos that are distributed through mobile phones and determines the original version of the mobile phone video for use as legal evidence. For this analysis, an experiment was conducted to find the unique characteristics of each mobile phone. The videos recorded by mobile phones were analyzed to establish the delay time of sound signals, and the differences between the delay times of sound signals for different mobile phones were traced by classifying their characteristics. Furthermore, the sound input signals for mobile phone videos used as legal evidence were analyzed to ascertain whether they have the unique characteristics of the original version. The objective of this study was to find a method for validating the use of mobile phone videos as legal evidence using mobile phones through differences in the delay times of sound input signals. © 2017 American Academy of Forensic Sciences.

Towards a Visual Quality Metric for Digital Video

NASA Technical Reports Server (NTRS)

Watson, Andrew B.

1998-01-01

The advent of widespread distribution of digital video creates a need for automated methods for evaluating visual quality of digital video. This is particularly so since most digital video is compressed using lossy methods, which involve the controlled introduction of potentially visible artifacts. Compounding the problem is the bursty nature of digital video, which requires adaptive bit allocation based on visual quality metrics. In previous work, we have developed visual quality metrics for evaluating, controlling, and optimizing the quality of compressed still images. These metrics incorporate simplified models of human visual sensitivity to spatial and chromatic visual signals. The challenge of video quality metrics is to extend these simplified models to temporal signals as well. In this presentation I will discuss a number of the issues that must be resolved in the design of effective video quality metrics. Among these are spatial, temporal, and chromatic sensitivity and their interactions, visual masking, and implementation complexity. I will also touch on the question of how to evaluate the performance of these metrics.

Automated Assessment of Visual Quality of Digital Video

NASA Technical Reports Server (NTRS)

Watson, Andrew B.; Ellis, Stephen R. (Technical Monitor)

1997-01-01

The advent of widespread distribution of digital video creates a need for automated methods for evaluating visual quality of digital video. This is particularly so since most digital video is compressed using lossy methods, which involve the controlled introduction of potentially visible artifacts. Compounding the problem is the bursty nature of digital video, which requires adaptive bit allocation based on visual quality metrics. In previous work, we have developed visual quality metrics for evaluating, controlling, and optimizing the quality of compressed still images[1-4]. These metrics incorporate simplified models of human visual sensitivity to spatial and chromatic visual signals. The challenge of video quality metrics is to extend these simplified models to temporal signals as well. In this presentation I will discuss a number of the issues that must be resolved in the design of effective video quality metrics. Among these are spatial, temporal, and chromatic sensitivity and their interactions, visual masking, and implementation complexity. I will also touch on the question of how to evaluate the performance of these metrics.

A real-time TV logo tracking method using template matching

NASA Astrophysics Data System (ADS)

Li, Zhi; Sang, Xinzhu; Yan, Binbin; Leng, Junmin

2012-11-01

A fast and accurate TV Logo detection method is presented based on real-time image filtering, noise eliminating and recognition of image features including edge and gray level information. It is important to accurately extract the optical template using the time averaging method from the sample video stream, and then different templates are used to match different logos in separated video streams with different resolution based on the topology features of logos. 12 video streams with different logos are used to verify the proposed method, and the experimental result demonstrates that the achieved accuracy can be up to 99%.

A video method to study Drosophila sleep.

PubMed

Zimmerman, John E; Raizen, David M; Maycock, Matthew H; Maislin, Greg; Pack, Allan I

2008-11-01

To use video to determine the accuracy of the infrared beam-splitting method for measuring sleep in Drosophila and to determine the effect of time of day, sex, genotype, and age on sleep measurements. A digital image analysis method based on frame subtraction principle was developed to distinguish a quiescent from a moving fly. Data obtained using this method were compared with data obtained using the Drosophila Activity Monitoring System (DAMS). The location of the fly was identified based on its centroid location in the subtracted images. The error associated with the identification of total sleep using DAMS ranged from 7% to 95% and depended on genotype, sex, age, and time of day. The degree of the total sleep error was dependent on genotype during the daytime (P < 0.001) and was dependent on age during both the daytime and the nighttime (P < 0.001 for both). The DAMS method overestimated sleep bout duration during both the day and night, and the degree of these errors was genotype dependent (P < 0.001). Brief movements that occur during sleep bouts can be accurately identified using video. Both video and DAMS detected a homeostatic response to sleep deprivation. Video digital analysis is more accurate than DAMS in fly sleep measurements. In particular, conclusions drawn from DAMS measurements regarding daytime sleep and sleep architecture should be made with caution. Video analysis also permits the assessment of fly position and brief movements during sleep.

On the use of video projectors for three-dimensional scanning

NASA Astrophysics Data System (ADS)

Juarez-Salazar, Rigoberto; Diaz-Ramirez, Victor H.; Robledo-Sanchez, Carlos; Diaz-Gonzalez, Gerardo

2017-08-01

Structured light projection is one of the most useful methods for accurate three-dimensional scanning. Video projectors are typically used as the illumination source. However, because video projectors are not designed for structured light systems, some considerations such as gamma calibration must be taken into account. In this work, we present a simple method for gamma calibration of video projectors. First, the experimental fringe patterns are normalized. Then, the samples of the fringe patterns are sorted in ascending order. The sample sorting leads to a simple three-parameter sine curve that is fitted using the Gauss-Newton algorithm. The novelty of this method is that the sorting process removes the effect of the unknown phase. Thus, the resulting gamma calibration algorithm is significantly simplified. The feasibility of the proposed method is illustrated in a three-dimensional scanning experiment.

Contact-free heart rate measurement using multiple video data

NASA Astrophysics Data System (ADS)

Hung, Pang-Chan; Lee, Kual-Zheng; Tsai, Luo-Wei

2013-10-01

In this paper, we propose a contact-free heart rate measurement method by analyzing sequential images of multiple video data. In the proposed method, skin-like pixels are firstly detected from multiple video data for extracting the color features. These color features are synchronized and analyzed by independent component analysis. A representative component is finally selected among these independent component candidates to measure the HR, which achieves under 2% deviation on average compared with a pulse oximeter in the controllable environment. The advantages of the proposed method include: 1) it uses low cost and high accessibility camera device; 2) it eases users' discomfort by utilizing contact-free measurement; and 3) it achieves the low error rate and the high stability by integrating multiple video data.

Semantic Information Extraction of Lanes Based on Onboard Camera Videos

NASA Astrophysics Data System (ADS)

Tang, L.; Deng, T.; Ren, C.

2018-04-01

In the field of autonomous driving, semantic information of lanes is very important. This paper proposes a method of automatic detection of lanes and extraction of semantic information from onboard camera videos. The proposed method firstly detects the edges of lanes by the grayscale gradient direction, and improves the Probabilistic Hough transform to fit them; then, it uses the vanishing point principle to calculate the lane geometrical position, and uses lane characteristics to extract lane semantic information by the classification of decision trees. In the experiment, 216 road video images captured by a camera mounted onboard a moving vehicle were used to detect lanes and extract lane semantic information. The results show that the proposed method can accurately identify lane semantics from video images.

Do abyssal scavengers use phytodetritus as a food resource? Video and biochemical evidence from the Atlantic and Mediterranean

NASA Astrophysics Data System (ADS)

Jeffreys, Rachel M.; Lavaleye, Marc S. S.; Bergman, Magda J. N.; Duineveld, Gerard C. A.; Witbaard, Rob

2011-04-01

Deep-sea benthic communities derive their energetic requirements from overlying surface water production, which is deposited at the seafloor as phytodetritus. Benthic invertebrates are the primary consumers of this food source, with deep-sea fish at the top of the trophic hierarchy. Recently, we demonstrated with the use of baited cameras that macrourid fish rapidly respond to and feed vigorously on large plant food falls mimicked by spinach ( Jeffreys et al., 2010). Since higher plant remains are scarce in the deep-sea, with the exception of canyons, where terrestrial material has been observed, these results led us to ask if a more commonly documented plant material i.e. phytodetritus might form a food source for deep-sea fish and mobile scavenging megafauna. We simulated a phytodetritus dump at the seafloor in two contrasting environments (1) the NE Atlantic where carpets of phytodetritus have been previously observed and (2) the oligotrophic western Mediterranean, where the deposition of phytodetritus at the seafloor is a rare occurrence. We recorded the response of the scavenging fauna using an in situ benthic lander equipped with baited time-lapse cameras. In the NE Atlantic at 3000 m, abyssal macrourids and cusk-eels were observed ingesting the phytodetritus. The phytodetrital patch was significantly diminished within 2 h. Abundance estimates calculated from first arrival times of macrourids at the phytodetrital patch in the Atlantic corresponded with abundance estimates from video-transect indicating that fish were attracted to the scent of phytodetrital bait. In contrast to this, in the western Mediterranean at 2800 m a single macrourid was observed investigating the phytodetrital patch but did not feed from it. The phytodetrital patch was significantly diminished within 6.5 h as a result of mainly invertebrate activity. At 1900 m, Lepidion lepidion was observed near the lander and the bait, but did not feed. The phytodetrital patch remained intact until the end of the experiment. In the deployments in the Mediterranean abundance estimates from first arrival times at the bait, corrected for their body size, were lower than estimates obtained from video-transects and trawl catches. This suggests that the Mediterranean fish were not readily attracted to this food source. In contrast, invertebrates in the Balearic Sea were observed ingesting the phytodetritus bait despite the rare occurrence of phytodetritus dumps in the Mediterranean. Stable isotope values of the fish at both study sites, set within the context of the benthic food web, did not demonstrate a strong trophic link to phytodetritus. Fatty acid profiles of these fish indicated a strong link between their lipid pool and primary producers i.e. phytoplankton, which may be attributed to trophic transfer. The usefulness of fatty acid biomarkers in ascertaining deep-sea fish diets is discussed. Our study suggests that the abyssal grenadier C. armatus on the Atlantic Iberian margin is attracted to phytodetritus. However the exact contribution of this food source to the diet of macrourids in this area remains unresolved.

Circumferential suture technique for esophageal transection to treat esophageal variceal bleeding.

PubMed

Jeng, L B; Chen, M F

1993-01-01

The EEA stapler has been used routinely for esophageal transection to treat esophageal variceal bleeding for some time. It carries the risk of postoperative leakage and is not suitable in those cases receiving recent sclerotherapy. The circumferential suture technique presented in this paper can be used in any situation requiring esophageal transection. It has been utilized by us in twenty-two emergent cases with good results.

Analysis of down wood volme and percent ground cover for the Missouri Ozark forest ecosystem project

Treesearch

Laura A. Herbeck

2000-01-01

Volume and percent ground cover of down wood were estimated on the MOFEP sites from two separate sampling inventories, line transects and fixed-area plots. Line transects were used to sample down wood in the 1990-91 and 1994-95 inventories and fixed-area plots were used in an additional inventory in 1995. Line transect inventories estimated a range in ground cover...

A Brain-Machine-Muscle Interface for Restoring Hindlimb Locomotion after Complete Spinal Transection in Rats

PubMed Central

Alam, Monzurul; Chen, Xi; Zhang, Zicong; Li, Yan; He, Jufang

2014-01-01

A brain-machine interface (BMI) is a neuroprosthetic device that can restore motor function of individuals with paralysis. Although the feasibility of BMI control of upper-limb neuroprostheses has been demonstrated, a BMI for the restoration of lower-limb motor functions has not yet been developed. The objective of this study was to determine if gait-related information can be captured from neural activity recorded from the primary motor cortex of rats, and if this neural information can be used to stimulate paralysed hindlimb muscles after complete spinal cord transection. Neural activity was recorded from the hindlimb area of the primary motor cortex of six female Sprague Dawley rats during treadmill locomotion before and after mid-thoracic transection. Before spinal transection there was a strong association between neural activity and the step cycle. This association decreased after spinal transection. However, the locomotive state (standing vs. walking) could still be successfully decoded from neural recordings made after spinal transection. A novel BMI device was developed that processed this neural information in real-time and used it to control electrical stimulation of paralysed hindlimb muscles. This system was able to elicit hindlimb muscle contractions that mimicked forelimb stepping. We propose this lower-limb BMI as a future neuroprosthesis for human paraplegics. PMID:25084446

Laparoscopic repair of hernia in children: Comparison between ligation and nonligation of sac.

PubMed

Pant, Nitin; Aggarwal, Satish Kumar; Ratan, Simmi K

2014-04-01

The essence of the current techniques of laparoscopic hernia repair in children is suture ligation of the neck of the hernia sac at the deep ring with or without its transection. Some studies show that during open hernia repair, after transection at the neck it can be left unsutured without any consequence. This study was aimed to see if the same holds true for laparoscopic hernia repair. Sixty patients (52 boys and eight girls, 12-144 months) with indirect inguinal hernia were randomized for laparoscopic repair either by transection of the sac alone (Group I) or transection plus suture ligation of sac at the neck (Group II). Outcome was assessed in terms of time taken for surgery, recurrence, and other complications. Thirty-eight hernia units in 28 patients were repaired by transection alone (Group I) and 34 hernia units in 29 patients were repaired by transection and suture ligation (Group II). Three patients were found to have no hernia on laparoscopy. Recurrence rate and other complications were not significantly different in the two groups. All recurrences occurred in hernias with ring size more than 10 mm. Laparoscopic repair of hernia by circumferential incision of the peritoneum at the deep ring is as effective as incision plus ligation of the sac.

A brain-machine-muscle interface for restoring hindlimb locomotion after complete spinal transection in rats.

PubMed

Alam, Monzurul; Chen, Xi; Zhang, Zicong; Li, Yan; He, Jufang

2014-01-01

A brain-machine interface (BMI) is a neuroprosthetic device that can restore motor function of individuals with paralysis. Although the feasibility of BMI control of upper-limb neuroprostheses has been demonstrated, a BMI for the restoration of lower-limb motor functions has not yet been developed. The objective of this study was to determine if gait-related information can be captured from neural activity recorded from the primary motor cortex of rats, and if this neural information can be used to stimulate paralysed hindlimb muscles after complete spinal cord transection. Neural activity was recorded from the hindlimb area of the primary motor cortex of six female Sprague Dawley rats during treadmill locomotion before and after mid-thoracic transection. Before spinal transection there was a strong association between neural activity and the step cycle. This association decreased after spinal transection. However, the locomotive state (standing vs. walking) could still be successfully decoded from neural recordings made after spinal transection. A novel BMI device was developed that processed this neural information in real-time and used it to control electrical stimulation of paralysed hindlimb muscles. This system was able to elicit hindlimb muscle contractions that mimicked forelimb stepping. We propose this lower-limb BMI as a future neuroprosthesis for human paraplegics.

Calpains mediate axonal cytoskeleton disintegration during Wallerian degeneration

PubMed Central

Ma, Marek; Ferguson, Toby A.; Schoch, Kathleen M.; Li, Jian; Qian, Yaping; Shofer, Frances S.; Saatman, Kathryn E.; Neumar, Robert W.

2013-01-01

In both the central nervous system (CNS) and peripheral nervous system (PNS), transected axons undergo Wallerian degeneration. Even though Augustus Waller first described this process after transection of axons in 1850, the molecular mechanisms may be shared, at least in part, by many human diseases. Early pathology includes failure of synaptic transmission, target denervation, and granular disintegration of the axonal cytoskeleton (GDC). The Ca2+-dependent proteases calpains have been implicated in GDC but causality has not been established. To test the hypothesis that calpains play a causal role in axonal and synaptic degeneration in vivo, we studied transgenic mice that express human calpastatin (hCAST), the endogenous calpain inhibitor, in optic and sciatic nerve axons. Five days after optic nerve transection and 48 hours after sciatic nerve transection, robust neurofilament proteolysis observed in wild-type controls was reduced in hCAST transgenic mice. Protection of the axonal cytoskeleton in sciatic nerves of hCAST mice was nearly complete 48 hours post-transection. In addition, hCAST expression preserved the morphological integrity of neuromuscular junctions. However, compound muscle action potential amplitudes after nerve transection were similar in wild-type and hCAST mice. These results, in total, provide direct evidence that calpains are responsible for the morphological degeneration of the axon and synapse during Wallerian degeneration. PMID:23542511

IR Hiding: A Method to Prevent Video Re-shooting by Exploiting Differences between Human Perceptions and Recording Device Characteristics

NASA Astrophysics Data System (ADS)

Yamada, Takayuki; Gohshi, Seiichi; Echizen, Isao

A method is described to prevent video images and videos displayed on screens from being re-shot by digital cameras and camcorders. Conventional methods using digital watermarking for re-shooting prevention embed content IDs into images and videos, and they help to identify the place and time where the actual content was shot. However, these methods do not actually prevent digital content from being re-shot by camcorders. We developed countermeasures to stop re-shooting by exploiting the differences between the sensory characteristics of humans and devices. The countermeasures require no additional functions to use-side devices. It uses infrared light (IR) to corrupt the content recorded by CCD or CMOS devices. In this way, re-shot content will be unusable. To validate the method, we developed a prototype system and implemented it on a 100-inch cinema screen. Experimental evaluations showed that the method effectively prevents re-shooting.

Seismic Reflection Transect across the Central Iberian Zone (Iberian Massif): The ALCUDIA project

NASA Astrophysics Data System (ADS)

Carbonell, R.; Simancas, F.; Martinez-Poyatos, D.; Ayarza, P.; Gonzalez, P.; Tejero, R.; Martín-Parra, L.; Matas, J.; Gonzalez-Lodeiro, F.; Pérez-Estaún, A.; García-Lobon, J.; Mansilla, L.; Palomeras, I.

2007-12-01

The lithosphere of the Central Iberian Zone (CIZ) differs from that of the southwestern Iberian Massif. They are limited by a suture zone. The seismic reflection profile IBERSEIS suggested that the activity of a Carboniferous mantle plume resulted in abundant intrusions of mafic magmas in the mid-to-lower crust which resulted in a singular crustal evolution. The current knowledge of the area based mostly in surface geological mapping suggests that basic magmatism continues further towards the north, indicating that the mantle plume may have affected a bigger area up to the Tajo depression. Furthermore, the existence of the Almadén mine, one of the largest mercury mine in the world within the CIZ, favour that the crust in this area is the result of anomalous lithospheric processes. Accordingly, the ALCUDIA project has been lauched aiming to study the structure and nature of the lithosphere of the CIZ. It includes the acquisition of a deep high resolution seismic reflection transect, detailed geological mapping, kinematic, petrologic and geochemical studies, and other geophysical studies (potential field methods). This new profile extends the previous IBERSEIS Transect towards the northeast, completing almost 600 km of deep seismic profiles, crossing the southern half of the Iberian Variscides. The transect crosses some important structures, such as the Toledo fault, Santa Elena Fault, Alcudia anticline, Almadén syncline, and some major magnetic anomalies. The preliminary results reveal that the crust is 30 km thick in average, with a horizontal Moho, a highly reflective mid-to-lower crust with a few mantle reflectors and well defined features in the upper crust with the indication of detachments zones that might link to the mid- crustal reflective zone.

Controls on compound specific 2H/1H of leaf waxes along a North American monsoonal transect

NASA Astrophysics Data System (ADS)

Berke, M. A.; Tipple, B. J.; Hambach, B.; Ehleringer, J. R.

2013-12-01

The use of hydrogen isotope ratios of sedimentary n-alkanes from leaf waxes has become an important method for the reconstruction of paleohydrologic conditions. Ideally, the relationship between lipid 2H/1H values and source water is one-to-one. But the extent to which the 2H/1H values are altered between initial source water and lipid 2H/1H values varies by plant type and environment. Additionally, these variables may be confounded by use of varied source waters by plants in the same ecosystem. Here, we use a transect study across the arid southwestern landscape of the United States, which is heavily influenced by the North American Monsoon, to study the variability in 2H/1H values of leaf waxes in co-occurring plants from Tucson, Arizona to Salt Lake City, Utah. Perennials, including rabbit brush (Chrysothamnus nauseosus), sagebrush (Artemisia tridentata), and gambel oak (Quercus gambelii) and an annual plant, sunflower (Helianthus annuus), were chosen for their wide geographic distribution along the entire transect. Our results indicate that n-alkane distribution for each plant was similar and generally showed no relationship to environmental variables (elevation, mean annual precipitation, latitude, and temperature). However, we find evidence of n-alkane 2H/1H value relating to transect latitude, a relationship that is weaker for all samples combined than the strong individual correlation for each plant species. Further, these 2H/1H values suggest that not all plants in the monsoon region utilize monsoon-delivered precipitation. These results imply an adaptation to discontinuous spatial coverage and amount of monsoonal precipitation and suggest care must be taken when assuming consistent source water for different plants, particularly in regions with highly seasonal precipitation delivery.

Controls on subsurface methane fluxes and shallow gas formation in Baltic Sea sediment (Aarhus Bay, Denmark)

NASA Astrophysics Data System (ADS)

Flury, Sabine; Røy, Hans; Dale, Andrew W.; Fossing, Henrik; Tóth, Zsuzsanna; Spiess, Volkhard; Jensen, Jørn Bo; Jørgensen, Bo Barker

2016-09-01

Shallow gas accumulates in coastal marine sediments when the burial rate of reactive organic matter beneath the sulfate zone is sufficiently high and the methanogenic zone is sufficiently deep. We investigated the controls on methane production and free methane gas accumulation along a 400 m seismo-acoustic transect across a sharp transition from gas-free into gas-bearing sediment in Aarhus Bay (Denmark). Twelve gravity cores were taken, in which the pore water was analyzed for inorganic solutes while rates of organic carbon mineralization were measured experimentally by 35SO42- radiotracer method. The thickness of organic-rich Holocene mud increased from 5 to 10 m along the transect concomitant with a shallowing of the depth of the sulfate-methane transition from >4 m to 2.5 m. In spite of drastic differences in the distribution of methane and sulfate in the sediment along the transect, there were only small differences in total mineralization, and methanogenesis was only equivalent to about 1% of sulfate reduction. Shallow gas appeared where the mud thickness exceeded 8-9 m. Rates of methanogenesis increased along the transect as did the upward diffusive flux of methane. Interestingly, the increase in the sedimentation rate and Holocene mud thickness had only a modest direct effect on methanogenesis rates in deep sediments. This increase in methane flux, however, triggered a shallowing of the sulfate-methane transition which resulted in a large increase in methanogenesis at the top of the methanogenic zone. Thus, our results demonstrate a positive feedback mechanism that causes a strong enhancement of methanogenesis and explains the apparently abrupt appearance of gas when a threshold thickness of organic-rich mud is exceeded.

Geophysical Investigation of a Thermokarst Lake Talik in Continuous Permafrost

NASA Astrophysics Data System (ADS)

Creighton, A.; Parsekian, A.; Arp, C. D.; Jones, B. M.; Babcock, E.; Bondurant, A. C.

2016-12-01

On the Arctic Coastal Plain (ACP) of northern Alaska, shallow thermokarst lakes cover up to 25% of the landscape. These lakes occupy depressions created by the subsidence of thawed, ice-rich permafrost. Areas of unfrozen sediment, or taliks, can form under lakes that have a mean annual bottom temperature greater than 0°C. The geometry of these taliks, as well as the processes that create them, are important for understanding interactions between surface water, groundwater, and carbon cycling. Non-invasive geophysical methods are a useful means to study talik sediments as borehole studies yield few data points, and the contrast between unfrozen and frozen sediments is an ideal geophysical target. To study talik configuration associated with an actively expanding thermokarst lake, we conducted a geophysical transect across Peatball Lake. This lake has an estimated initiation age of 1400 calendar years BP. Over the past 60 years, lake surface area has increased through thermal and mechanical shoreline erosion. A talik of previously unknown thickness likely exists below Peatball Lake. We conducted a transect of transient electromagnetic soundings across the lake extending into the surrounding terrestrial environment. Since permafrost has relatively high resistivity compared to talik sediments, the interpreted electrical structure of the subsurface likely reflects talik geometry. We also conducted nuclear magnetic resonance soundings at representative locations along the transect. These measurements can provide data on sub-lake sediment properties including water content. Together, these measurements resolve the talik structure across the lake transect and showed evidence of varying talik thicknesses from the lake edge to center. These is no evidence of a talik at the terrestrial control sites. These results can help constrain talik development models and thus provide insight into Arctic and permafrost processes in the face of a changing climate.

Surveying drainage culvert use by carnivores: sampling design and cost-benefit analyzes of track-pads vs. video-surveillance methods.

PubMed

Mateus, Ana Rita A; Grilo, Clara; Santos-Reis, Margarida

2011-10-01

Environmental assessment studies often evaluate the effectiveness of drainage culverts as habitat linkages for species, however, the efficiency of the sampling designs and the survey methods are not known. Our main goal was to estimate the most cost-effective monitoring method for sampling carnivore culvert using track-pads and video-surveillance. We estimated the most efficient (lower costs and high detection success) interval between visits (days) when using track-pads and also determined the advantages of using each method. In 2006, we selected two highways in southern Portugal and sampled 15 culverts over two 10-day sampling periods (spring and summer). Using the track-pad method, 90% of the animal tracks were detected using a 2-day interval between visits. We recorded a higher number of crossings for most species using video-surveillance (n = 129) when compared with the track-pad technique (n = 102); however, the detection ability using the video-surveillance method varied with type of structure and species. More crossings were detected in circular culverts (1 m and 1.5 m diameter) than in box culverts (2 m to 4 m width), likely because video cameras had a reduced vision coverage area. On the other hand, carnivore species with small feet such as the common genet Genetta genetta were detected less often using the track-pad surveying method. The cost-benefit analyzes shows that the track-pad technique is the most appropriate technique, but video-surveillance allows year-round surveys as well as the behavior response analyzes of species using crossing structures.

Biomechanical Outcomes After Bio-enhanced Anterior Cruciate Ligament Repair and Anterior Cruciate Ligament Reconstruction Are Equal in a Porcine Model

PubMed Central

Vavken, Patrick; Fleming, Braden C.; Mastrangelo, Ashley N.; Machan, Jason T.; Murray, Martha M.

2011-01-01

Purpose The objective of this study was to compare the biomechanical outcomes of a new method of anterior cruciate ligament (ACL) treatment, bio-enhanced ACL repair, with ACL reconstruction in a large animal model. Methods Twenty-four skeletally immature pigs underwent unilateral ACL transection and were randomly allocated to receive bio-enhanced ACL repair with a collagen-platelet composite, allograft (bone–patellar tendon– bone) reconstruction, or no further treatment (n = 8 for each group). The structural properties and anteroposterior laxity of the experimental and contralateral ACL-intact knees were measured 15 weeks postoperatively. All dependent variables were normalized to those of the contralateral knee and compared by use of generalized linear mixed models. Results After 15 weeks, bio-enhanced ACL repair and ACL reconstruction produced superior biomechanical outcomes to ACL transection. However, there were no significant differences between bio-enhanced ACL repair and ACL reconstruction for maximum load (P = .4745), maximum displacement (P = .4217), or linear stiffness (P = .6327). There were no significant differences between the 2 surgical techniques in anteroposterior laxity at 30° (P = .7947), 60° (P = .6270), or 90° (P = .9008). Conclusions Bio-enhanced ACL repair produced biomechanical results that were not different from ACL reconstruction in a skeletally immature, large animal model, although the variability associated with both procedures was large. Both procedures produced significantly improved results over ACL transection, showing that both were effective in this model. Clinical Relevance Bio-enhanced ACL repair may 1 day provide an alternative treatment option for ACL injury. PMID:22261137

Heat tracing to determine spatial patterns of hyporheic exchange across a river transect

NASA Astrophysics Data System (ADS)

Lu, Chengpeng; Chen, Shuai; Zhang, Ying; Su, Xiaoru; Chen, Guohao

2017-09-01

Significant spatial variability of water fluxes may exist at the water-sediment interface in river channels and has great influence on a variety of water issues. Understanding the complicated flow systems controlling the flux exchanges along an entire river is often limited due to averaging of parameters or the small number of discrete point measurements usually used. This study investigated the spatial pattern of the hyporheic flux exchange across a river transect in China, using the heat tracing approach. This was done with measurements of temperature at high spatial resolution during a 64-h monitoring period and using the data to identify the spatial pattern of the hyporheic exchange flux with the aid of a one-dimensional conduction-advection-dispersion model (VFLUX). The threshold of neutral exchange was considered as 126 L m-2 d-1 in this study and the heat tracing results showed that the change patterns of vertical hyporheic flux varied with buried depth along the river transect; however, the hyporheic flux was not simply controlled by the streambed hydraulic conductivity and water depth in the river transect. Also, lateral flow dominated the hyporheic process within the shallow high-permeability streambed, while the vertical flow was dominant in the deep low-permeability streambed. The spatial pattern of hyporheic exchange across the river transect was naturally controlled by the heterogeneity of the streambed and the bedform of the stream cross-section. Consequently, a two-dimensional conceptual illustration of the hyporheic process across the river transect is proposed, which could be applicable to river transects of similar conditions.

Chondroprotective effects of zoledronic acid on articular cartilage in dogs with experimentally induced osteoarthritis.

PubMed

Dearmin, Michael G; Trumble, Troy N; García, Anapatricia; Chambers, Jon N; Budsberg, Steven C

2014-04-01

To assess effects of zoledronic acid on biomarkers, radiographic scores, and gross articular cartilage changes in dogs with induced osteoarthritis. 21 purpose-bred hound-type dogs. The left stifle joint of each dog was examined arthroscopically to determine initial articular cartilage status, which was followed by cranial cruciate ligament (CrCL) transection to induce osteoarthritis. Dogs were assigned to 3 groups (control group, low dose [10 μg of zoledronic acid/kg], or high dose [25 μg of zoledronic acid/kg). Treatments were administered SC every 3 months for 1 year beginning the day after CrCL transection. Serum and synovial fluid samples and radiographs were obtained 0, 1, 3, 6, 9, and 12 months after transection. At 12 months, each joint was scored for cartilage defects. Serum and synovial fluid biomarkers of bone and cartilage turnover (bone-specific alkaline phosphatase, type I and II collagen, carboxy-propeptide of type II collagen, and chondroitin sulfate 846) were analyzed with ELISAs. The high-dose group had fewer total articular defects and lower severity scores in CrCL-transected stifle joints than did the control group. In addition, the high-dose group had significantly less change in collagenase cleavage of type I or II collagen in the synovial fluid at 1 and 3 months after CrCL transection than did the control group and also had greater changes in bone-specific alkaline phosphatase in synovial fluid at 3 months after CrCL transection than did the control group. Zoledronic acid had a chondroprotective effect in dogs with a transected CrCL.

Moderating Factors of Video-Modeling with Other as Model: A Meta-Analysis of Single-Case Studies

ERIC Educational Resources Information Center

Mason, Rose A.; Ganz, Jennifer B.; Parker, Richard I.; Burke, Mack D.; Camargo, Siglia P.

2012-01-01

Video modeling with other as model (VMO) is a more practical method for implementing video-based modeling techniques, such as video self-modeling, which requires significantly more editing. Despite this, identification of contextual factors such as participant characteristics and targeted outcomes that moderate the effectiveness of VMO has not…

Video Use in Teacher Education: A Survey of Teacher-Educators' Practices across Disciplines

ERIC Educational Resources Information Center

Arya, Poonam; Christ, Tanya; Chiu, Ming Ming

2016-01-01

Video methods utilize tenets of high quality teacher education and support education students' learning and application of learning to teaching practices. However, how frequently video is used in teacher education, and in what ways is unknown. Therefore, this study used survey data to identify the extent to which 94 teacher-educators used video in…

A Comparison of Video Formats for Online Teaching

ERIC Educational Resources Information Center

Malaga, Ross A.; Koppel, Nicole B.

2017-01-01

The use of video to deliver content to students online has become increasingly popular. However, educators are often plagued with the question of which format to use to deliver asynchronous video material. Whether it is a College or University committing to a common video format or an individual instructor selecting the method that works best for…

YouTube as a potential training method for laparoscopic cholecystectomy

PubMed Central

Lee, Jun Suh; Seo, Ho Seok

2015-01-01

Purpose The purpose of this study was to analyze the educational quality of laparoscopic cholecystectomy (LC) videos accessible on YouTube, one of the most important sources of internet-based medical information. Methods The keyword 'laparoscopic cholecystectomy' was used to search on YouTube and the first 100 videos were analyzed. Among them, 27 videos were excluded and 73 videos were included in the study. An arbitrary score system for video quality, devised from existing LC guidelines, were used to evaluate the quality of the videos. Video demographics were analyzed by the quality and source of the video. Correlation analysis was performed. Results When analyzed by video quality, 11 (15.1%) were evaluated as 'good', 40 (54.8%) were 'moderate', and 22 (30.1%) were 'poor', and there were no differences in length, views per day, or number of likes, dislikes, and comments. When analyzed by source, 27 (37.0%) were uploaded by primary centers, 20 (27.4%) by secondary centers, 15 (20.5%) by tertiary centers, 5 (6.8%) by academic institutions, and 6 (8.2%) by commercial institutions. The mean score of the tertiary center group (6.0 ± 2.0) was significantly higher than the secondary center group (3.9 ± 1.4, P = 0.001). The video score had no correlation with views per day or number of likes. Conclusion Many LC videos are accessible on YouTube with varying quality. Videos uploaded by tertiary centers showed the highest educational value. This discrepancy in video quality was not recognized by viewers. More videos with higher quality need to be uploaded, and an active filtering process is necessary. PMID:26236699

Focal Experimental Injury Leads to Widespread Gene Expression and Histologic Changes in Equine Flexor Tendons

PubMed Central

Jacobsen, Else; Dart, Andrew J.; Mondori, Takamitsu; Horadogoda, Neil; Jeffcott, Leo B.; Little, Christopher B.; Smith, Margaret M.

2015-01-01

It is not known how extensively a localised flexor tendon injury affects the entire tendon. This study examined the extent of and relationship between histopathologic and gene expression changes in equine superficial digital flexor tendon after a surgical injury. One forelimb tendon was hemi-transected in six horses, and in three other horses, one tendon underwent a sham operation. After euthanasia at six weeks, transected and control (sham and non-operated contralateral) tendons were regionally sampled (medial and lateral halves each divided into six 3cm regions) for histologic (scoring and immunohistochemistry) and gene expression (real time PCR) analysis of extracellular matrix changes. The histopathology score was significantly higher in transected tendons compared to control tendons in all regions except for the most distal (P ≤ 0.03) with no differences between overstressed (medial) and stress-deprived (lateral) tendon halves. Proteoglycan scores were increased by transection in all but the most proximal region (P < 0.02), with increased immunostaining for aggrecan, biglycan and versican. After correcting for location within the tendon, gene expression for aggrecan, versican, biglycan, lumican, collagen types I, II and III, MMP14 and TIMP1 was increased in transected tendons compared with control tendons (P < 0.02) and decreased for ADAMTS4, MMP3 and TIMP3 (P < 0.001). Aggrecan, biglycan, fibromodulin, and collagen types I and III expression positively correlated with all histopathology scores (P < 0.001), whereas lumican, ADAMTS4 and MMP14 expression positively correlated only with collagen fiber malalignment (P < 0.001). In summary, histologic and associated gene expression changes were significant and widespread six weeks after injury to the equine SDFT, suggesting rapid and active development of tendinopathy throughout the entire length of the tendon. These extensive changes distant to the focal injury may contribute to poor functional outcomes and re-injury in clinical cases. Our data suggest that successful treatments of focal injuries will need to address pathology in the entire tendon, and that better methods to monitor the development and resolution of tendinopathy are required. PMID:25837713

[Diagnosis and treatment of strabismus caused by nasal endoscopic surgery].

PubMed

Ai, L K; Wu, X; Wang, J N; Li, J; Wu, Y; Zhou, J; Song, W X; Guo, R L

2017-12-11

Objective: Strabismus with diplopia is the main orbital complication of functional endoscopic sinus surgery (FESS). This study was to analyze clinical findings, treatment and outcomes of such cases. Methods: Retrospective case series. Twenty-three cases were divided into 3 groups based on the disease severity: group A, partial transection of the medial rectus muscle, group B, complete transection of the medical rectus, group C, transection of the medial rectus combined with the other orbital injuries. Complete ophthalmology examinations, including eye alignment, eye motility, force duction test, force generation test, general eye exam, and medical imaging (orbital CT or MRI), were performed for each case. The treatment included botulinum toxin (Botox) injection to the lateral rectus muscle, transposition of the vertical rectus muscle, and orbital surgery if needed. Results: In group A with Botox injection, all the cases achieved single vision in primary position, but still remained some adduction weakness. In group B treated by vertical transposition surgery combined with Botox, 22% of the cases got single vision in primary gaze. In group C, even with more efforts of treatment, the cases with orbital injury can only get cosmetic improvement, and diplopia and adduction dysfunction were found in most cases. Conclusions: Due to the variety of the complications of FESS, force duction test is a crucial exam to detect the direction and severity of synechia in the orbit, which will give solid information to surgery approach as well as prognosis. Botox injection at early stage will minimize the contraction of antagonist lateral rectus, helping to postpone the transposition surgery which may cause anterior segment ischemia when performed right after the medial rectus transection injury. Botox may even reduce the synechia by minimizing the scarring process. Partial vertical rectus transposition combined with muscle resection may effectively correct the eye misalignment in primary gaze and improve eye motility. The prognosis of FESS induced orbital complications is quite related with the severity of the injury. Botox combined with surgery may help medial rectus transection cases to achieve single vision in primary gaze, but when there is any other orbital injury, treatment may only improve cosmetic appearance. (Chin J Ophthalmol, 2017, 53: 917-923) .

Video copy protection and detection framework (VPD) for e-learning systems

NASA Astrophysics Data System (ADS)

ZandI, Babak; Doustarmoghaddam, Danial; Pour, Mahsa R.

2013-03-01

This Article reviews and compares the copyright issues related to the digital video files, which can be categorized as contended based and Digital watermarking copy Detection. Then we describe how to protect a digital video by using a special Video data hiding method and algorithm. We also discuss how to detect the copy right of the file, Based on expounding Direction of the technology of the video copy detection, and Combining with the own research results, brings forward a new video protection and copy detection approach in terms of plagiarism and e-learning systems using the video data hiding technology. Finally we introduce a framework for Video protection and detection in e-learning systems (VPD Framework).

Applying aerial digital photography as a spectral remote sensing technique for macrophytic cover assessment in small rural streams

NASA Astrophysics Data System (ADS)

Anker, Y.; Hershkovitz, Y.; Gasith, A.; Ben-Dor, E.

2011-12-01

Although remote sensing of fluvial ecosystems is well developed, the tradeoff between spectral and spatial resolutions prevents its application in small streams (<3m width). In the current study, a remote sensing approach for monitoring and research of small ecosystem was developed. The method is based on differentiation between two indicative vegetation species out of the ecosystem flora. Since when studied, the channel was covered mostly by a filamentous green alga (Cladophora glomerata) and watercress (Nasturtium officinale), these species were chosen as indicative; nonetheless, common reed (Phragmites australis) was also classified in order to exclude it from the stream ROI. The procedure included: A. For both section and habitat scales classifications, acquisition of aerial digital RGB datasets. B. For section scale classification, hyperspectral (HSR) dataset acquisition. C. For calibration, HSR reflectance measurements of specific ground targets, in close proximity to each dataset acquisition swath. D. For habitat scale classification, manual, in-stream flora grid transects classification. The digital RGB datasets were converted to reflectance units by spectral calibration against colored reference plates. These red, green, blue, white, and black EVA foam reference plates were measured by an ASD field spectrometer and each was given a spectral value. Each spectral value was later applied to the spectral calibration and radiometric correction of spectral RGB (SRGB) cube. Spectral calibration of the HSR dataset was done using the empirical line method, based on reference values of progressive grey scale targets. Differentiation between the vegetation species was done by supervised classification both for the HSR and for the SRGB datasets. This procedure was done using the Spectral Angle Mapper function with the spectral pattern of each vegetation species as a spectral end member. Comparison between the two remote sensing techniques and between the SRGB classification and the in-situ transects indicates that: A. Stream vegetation classification resolution is about 4 cm by the SRGB method compared to about 1 m by HSR. Moreover, this resolution is also higher than of the manual grid transect classification. B. The SRGB method is by far the most cost-efficient. The combination of spectral information (rather than the cognitive color) and high spatial resolution of aerial photography provides noise filtration and better sub-water detection capabilities than the HSR technique. C. Only the SRGB method applies for habitat and section scales; hence, its application together with in-situ grid transects for validation, may be optimal for use in similar scenarios.
The HSR dataset was first degraded to 17 bands with the same spectral range as the RGB dataset and also to a dataset with 3 equivalent bands

Evaluating environmental drivers of spatial variability in free-living nematode assemblages along the Portuguese margin

NASA Astrophysics Data System (ADS)

Lins, Lidia; Leliaert, Frederik; Riehl, Torben; Pinto Ramalho, Sofia; Alfaro Cordova, Eliana; Morgado Esteves, André; Vanreusel, Ann

2017-02-01

Understanding processes responsible for shaping biodiversity patterns on continental margins is an important requirement for comprehending anthropogenic impacts in these environments and further management of biodiversity. Continental margins perform crucial functions linked to key ecological processes which are mainly structured by surface primary productivity and particulate organic matter flux to the seafloor, but also by heterogeneity in seafloor characteristics. However, to what extent these processes control local and regional biodiversity remains unclear. In this study, two isobathic parallel transects located at the shelf break (300-400 m) and upper slope (1000 m) of the western Iberian margin were used to test how food input and sediment heterogeneity affect nematode diversity independently from the spatial factors geographical distance and water depth. We also examined the potential role of connectedness between both depth transects through molecular phylogenetic analyses. Regional generic diversity and turnover were investigated at three levels: within a station, between stations from the same depth transect, and between transects. High variability in food availability and high sediment heterogeneity at the shelf-break transect were directly linked to high diversity within stations and higher variation in community structure across stations compared to the upper slope transect. Contrastingly, environmental factors (food availability and sediment) did not vary significantly between stations located at the upper slope, and this lack of differences were also reflected in a low community turnover between these deeper stations. Finally, differences in nematode communities between both transects were more pronounced than differences within each of the isobathic transects, but these changes were paralleled by the previously mentioned environmental changes. These results suggest that changes in community structure are mainly dictated by environmental factors rather than spatial differences at the western Iberian margin. Furthermore, phylogenetic relationships revealed no evidence for depth-endemic lineages, indicating regular species interchanges across different depths.

Tracking and recognition face in videos with incremental local sparse representation model

NASA Astrophysics Data System (ADS)

Wang, Chao; Wang, Yunhong; Zhang, Zhaoxiang

2013-10-01

This paper addresses the problem of tracking and recognizing faces via incremental local sparse representation. First a robust face tracking algorithm is proposed via employing local sparse appearance and covariance pooling method. In the following face recognition stage, with the employment of a novel template update strategy, which combines incremental subspace learning, our recognition algorithm adapts the template to appearance changes and reduces the influence of occlusion and illumination variation. This leads to a robust video-based face tracking and recognition with desirable performance. In the experiments, we test the quality of face recognition in real-world noisy videos on YouTube database, which includes 47 celebrities. Our proposed method produces a high face recognition rate at 95% of all videos. The proposed face tracking and recognition algorithms are also tested on a set of noisy videos under heavy occlusion and illumination variation. The tracking results on challenging benchmark videos demonstrate that the proposed tracking algorithm performs favorably against several state-of-the-art methods. In the case of the challenging dataset in which faces undergo occlusion and illumination variation, and tracking and recognition experiments under significant pose variation on the University of California, San Diego (Honda/UCSD) database, our proposed method also consistently demonstrates a high recognition rate.

Measuring zebrafish turning rate.

PubMed

Mwaffo, Violet; Butail, Sachit; di Bernardo, Mario; Porfiri, Maurizio

2015-06-01

Zebrafish is becoming a popular animal model in preclinical research, and zebrafish turning rate has been proposed for the analysis of activity in several domains. The turning rate is often estimated from the trajectory of the fish centroid that is output by commercial or custom-made target tracking software run on overhead videos of fish swimming. However, the accuracy of such indirect methods with respect to the turning rate associated with changes in heading during zebrafish locomotion is largely untested. Here, we compare two indirect methods for the turning rate estimation using the centroid velocity or position data, with full shape tracking for three different video sampling rates. We use tracking data from the overhead video recorded at 60, 30, and 15 frames per second of zebrafish swimming in a shallow water tank. Statistical comparisons of absolute turning rate across methods and sampling rates indicate that, while indirect methods are indistinguishable from full shape tracking, the video sampling rate significantly influences the turning rate measurement. The results of this study can aid in the selection of the video capture frame rate, an experimental design parameter in zebrafish behavioral experiments where activity is an important measure.

A Comparison of Face to Face and Video-Based Self Care Education on Quality of Life of Hemodialysis Patients

PubMed Central

Hemmati Maslakpak, Masumeh; Shams, Shadi

2015-01-01

Background End stage renal disease negatively affects the patients’ quality of life. There are different educational methods to help these patients. This study was performed to compare the effectiveness of self-care education in two methods, face to face and video educational, on the quality of life in patients under treatment by hemodialysis in education-medical centers in Urmia. Methods In this quasi-experimental study, 120 hemodialysis patients were selected randomly; they were then randomly allocated to three groups: the control, face to face education and video education. For face to face group, education was given individually in two sessions of 35 to 45 minutes. For video educational group, CD was shown. Kidney Disease Quality Of Life- Short Form (KDQOL-SF) questionnaire was filled out before and two months after the intervention. Data analysis was performed in SPSS software by using one-way ANOVA. Results ANOVA test showed a statistically significant difference in the quality of life scores among the three groups after the intervention (P=0.024). After the intervention, Tukey’s post-hoc test showed a statistically significant difference between the two groups of video and face to face education regarding the quality of life (P>0.05). Conclusion Implementation of the face to face and video education methods improves the quality of life in hemodialysis patients. So, it is suggested that video educational should be used along with face to face education. PMID:26171412

An ROI multi-resolution compression method for 3D-HEVC

NASA Astrophysics Data System (ADS)

Ti, Chunli; Guan, Yudong; Xu, Guodong; Teng, Yidan; Miao, Xinyuan

2017-09-01

3D High Efficiency Video Coding (3D-HEVC) provides a significant potential on increasing the compression ratio of multi-view RGB-D videos. However, the bit rate still rises dramatically with the improvement of the video resolution, which will bring challenges to the transmission network, especially the mobile network. This paper propose an ROI multi-resolution compression method for 3D-HEVC to better preserve the information in ROI on condition of limited bandwidth. This is realized primarily through ROI extraction and compression multi-resolution preprocessed video as alternative data according to the network conditions. At first, the semantic contours are detected by the modified structured forests to restrain the color textures inside objects. The ROI is then determined utilizing the contour neighborhood along with the face region and foreground area of the scene. Secondly, the RGB-D videos are divided into slices and compressed via 3D-HEVC under different resolutions for selection by the audiences and applications. Afterwards, the reconstructed low-resolution videos from 3D-HEVC encoder are directly up-sampled via Laplace transformation and used to replace the non-ROI areas of the high-resolution videos. Finally, the ROI multi-resolution compressed slices are obtained by compressing the ROI preprocessed videos with 3D-HEVC. The temporal and special details of non-ROI are reduced in the low-resolution videos, so the ROI will be better preserved by the encoder automatically. Experiments indicate that the proposed method can keep the key high-frequency information with subjective significance while the bit rate is reduced.

Facial Nerve Repair: Fibrin Adhesive Coaptation versus Epineurial Suture Repair in a Rodent Model

PubMed Central

Knox, Christopher J.; Hohman, Marc H.; Kleiss, Ingrid J.; Weinberg, Julie S.; Heaton, James T.; Hadlock, Tessa A.

2013-01-01

Objectives/Hypothesis Repair of the transected facial nerve has traditionally been accomplished with microsurgical neurorrhaphy; however, fibrin adhesive coaptation (FAC) of peripheral nerves has become increasingly popular over the past decade. We compared functional recovery following suture neurorrhaphy to FAC in a rodent facial nerve model. Study Design Prospective, randomized animal study. Methods Sixteen rats underwent transection and repair of the facial nerve proximal to the pes anserinus. Eight animals underwent epineurial suture (ES) neurorrhaphy, and eight underwent repair with fibrin adhesive (FA). Surgical times were documented for all procedures. Whisking function was analyzed on a weekly basis for both groups across 15 weeks of recovery. Results Rats experienced whisking recovery consistent in time course and degree with prior studies of rodent facial nerve transection and repair. There were no significant differences in whisking amplitude, velocity, or acceleration between suture and FA groups. However, the neurorrhaphy time with FA was 70% shorter than for ES (P < 0.05). Conclusion Although we found no difference in whisking recovery between suture and FA repair of the main trunk of the rat facial nerve, the significantly shorter operative time for FA repair makes this technique an attractive option. The relative advantages of both techniques are discussed. PMID:23188676

A 3D-engineered porous conduit for peripheral nerve repair

PubMed Central

Tao, Jie; Hu, Yu; Wang, Shujuan; Zhang, Jiumeng; Liu, Xuan; Gou, Zhiyuan; Cheng, Hao; Liu, Qianqi; Zhang, Qianqian; You, Shenglan; Gou, Maling

2017-01-01

End-to-end neurorrhaphy is the most commonly used method for treating peripheral nerve injury. However, only 50% of patients can regain useful function after treating with neurorrhaphy. Here, we constructed a 3D-engineered porous conduit to promote the function recovery of the transected peripheral nerve after neurorrhaphy. The conduit that consisted of a gelatin cryogel was prepared by molding with 3D-printed moulds. Due to its porous structure and excellent mechanical properties, this conduit could be collapsed by the mechanical force and resumed its original shape after absorption of normal saline. This shape-memory property allowed a simply surgery process for installing the conduits. Moreover, the biodegradable conduit could prevent the infiltration of fibroblasts and reduce the risk of scar tissue, which could provide an advantageous environment for nerve regeneration. The efficiency of the conduits in assisting peripheral nerve regeneration after neurorrhaphy was evaluated in a rat sciatic nerve transected model. Results indicated that conduits significantly benefitted the recovery of the transected peripheral nerve after end-to-end neurorrhaphy on the static sciatic index (SSI), electrophysiological results and the re-innervation of the gastrocnemius muscle. This work demonstrates a biodegradable nerve conduit that has potentially clinical application in promoting the neurorrhaphy. PMID:28401914

Maximum ikelihood estimation for the double-count method with independent observers

USGS Publications Warehouse

Manly, Bryan F.J.; McDonald, Lyman L.; Garner, Gerald W.

1996-01-01

Data collected under a double-count protocol during line transect surveys were analyzed using new maximum likelihood methods combined with Akaike's information criterion to provide estimates of the abundance of polar bear (Ursus maritimus Phipps) in a pilot study off the coast of Alaska. Visibility biases were corrected by modeling the detection probabilities using logistic regression functions. Independent variables that influenced the detection probabilities included perpendicular distance of bear groups from the flight line and the number of individuals in the groups. A series of models were considered which vary from (1) the simplest, where the probability of detection was the same for both observers and was not affected by either distance from the flight line or group size, to (2) models where probability of detection is different for the two observers and depends on both distance from the transect and group size. Estimation procedures are developed for the case when additional variables may affect detection probabilities. The methods are illustrated using data from the pilot polar bear survey and some recommendations are given for design of a survey over the larger Chukchi Sea between Russia and the United States.

A parametric generalization of the Hayne estimator for line transect sampling

USGS Publications Warehouse

Burnham, Kenneth P.

1979-01-01

The Hayne model for line transect sampling is generalized by using an elliptical (rather than circular) flushing model for animal detection. By assuming the ration of major and minor axes lengths is constant for all animals, a model results which allows estimation of population density based directly upon sighting distances and sighting angles. The derived estimator of animal density is a generalization of the Hayne estimator for line transect sampling.

Toward enhancing the distributed video coder under a multiview video codec framework

NASA Astrophysics Data System (ADS)

Lee, Shih-Chieh; Chen, Jiann-Jone; Tsai, Yao-Hong; Chen, Chin-Hua

2016-11-01

The advance of video coding technology enables multiview video (MVV) or three-dimensional television (3-D TV) display for users with or without glasses. For mobile devices or wireless applications, a distributed video coder (DVC) can be utilized to shift the encoder complexity to decoder under the MVV coding framework, denoted as multiview distributed video coding (MDVC). We proposed to exploit both inter- and intraview video correlations to enhance side information (SI) and improve the MDVC performance: (1) based on the multiview motion estimation (MVME) framework, a categorized block matching prediction with fidelity weights (COMPETE) was proposed to yield a high quality SI frame for better DVC reconstructed images. (2) The block transform coefficient properties, i.e., DCs and ACs, were exploited to design the priority rate control for the turbo code, such that the DVC decoding can be carried out with fewest parity bits. In comparison, the proposed COMPETE method demonstrated lower time complexity, while presenting better reconstructed video quality. Simulations show that the proposed COMPETE can reduce the time complexity of MVME to 1.29 to 2.56 times smaller, as compared to previous hybrid MVME methods, while the image peak signal to noise ratios (PSNRs) of a decoded video can be improved 0.2 to 3.5 dB, as compared to H.264/AVC intracoding.

'People like me don't make things like that': Participatory video as a method for reducing leprosy-related stigma.

PubMed

Peters, R M H; Zweekhorst, M B M; van Brakel, W H; Bunders, J F G; Irwanto

2016-01-01

The Stigma Assessment and Reduction of Impact project aims to assess the effectiveness of stigma-reduction interventions in the field of leprosy. Participatory video seemed to be a promising approach to reducing stigma among stigmatized individuals (in this study the video makers) and the stigmatisers (video audience). This study focuses on the video makers and seeks to assess the impact on them of making a participatory video and to increase understanding of how to deal with foreseeable difficulties. Participants were selected on the basis of criteria and in collaboration with the community health centre. This study draws on six qualitative methods including interviews with the video makers and participant observation. Triangulation was used to increase the validity of the findings. Two videos were produced. The impact on participants ranged from having a good time to a greater sense of togetherness, increased self-esteem, individual agency and willingness to take action in the community. Concealment of leprosy is a persistent challenge, and physical limitations and group dynamics are also areas that require attention. Provided these three areas are properly taken into account, participatory video has the potential to address stigma at least at three levels - intrapersonal, interpersonal and community - and possibly more.

A Comparison of Four Different Beach Profiling Techniques at St Leonards, Victoria - An Example of a Collaborative Stakeholder Research Project

NASA Astrophysics Data System (ADS)

Cox, N. L.; Miner, A. S.; Wynn, N.; Turner, D.

2015-12-01

Many beaches in Australia are under attack from shoreline erosion due rising sea levels and the action of waves. St Leonard's beach, a tourist town on the Victorian coastline, is of concern from this destructive erosion and the threat to the economic stability of the town. The major cause of erosion in this area is related to waves created from strong to gale force north to north-easterly winds. This in turn produces a northerly longshore current along with sediment suspension leading to a negative sediment budget. Ongoing and systematic monitoring of the shoreline movement is important to ensure the coast is understood and effectively managed now and into the future. Coastal land managers and agencies are required to find 'cost-effective' and 'fit-for-purpose' coastal monitoring methodologies which are affordable and efficient. This project forges a collaboration of stakeholders from academia, public sector land manager, local government and the private sector to compare four different methods of obtaining beach profiles. The four methods of obtaining beach profiles used for comparison are: 1. traditional survey method along transects using a total station theodolite, 2. traditional survey method along transects using a builder's grade laser level, 3. a small multi-rotor unmanned aerial vehicle (UAV) to produce a full 3D digital surface model of the study area, and 4. an experimental stationary device to produce a limited 3D model along a designated transect using terrestrial photogrammetric approach via a small GPS enabled camera. Assessment is made by comparing the method's precision, spatial coverage, expertise and equipment requirements/costs, preparation time, field acquisition time, number of people required in the field, post-acquisition processing time, and applicability for community use. Whilst is must be very clearly stated that all methods proved to be successful, the preliminary results of the "workflow and resourcing" assessment ranked the methods in the following order from highest ranking: 1. Laser levelling, 2. Terrestrial Photogrammetry, 3. Total Station, and 4. UAV aerial survey. The outcomes of this collaboration will be of great use to coastal management organisations grappling with the effectiveness of the different types of methods which are available for measuring beach profiles.

Background estimation and player detection in badminton video clips using histogram of pixel values along temporal dimension

NASA Astrophysics Data System (ADS)

Peng, Yahui; Ma, Xiao; Gao, Xinyu; Zhou, Fangxu

2015-12-01

Computer vision is an important tool for sports video processing. However, its application in badminton match analysis is very limited. In this study, we proposed a straightforward but robust histogram-based background estimation and player detection methods for badminton video clips, and compared the results with the naive averaging method and the mixture of Gaussians methods, respectively. The proposed method yielded better background estimation results than the naive averaging method and more accurate player detection results than the mixture of Gaussians player detection method. The preliminary results indicated that the proposed histogram-based method could estimate the background and extract the players accurately. We conclude that the proposed method can be used for badminton player tracking and further studies are warranted for automated match analysis.

Displays of dabbing marijuana extracts on YouTube

PubMed Central

Krauss, Melissa J.; Sowles, Shaina J.; Mylvaganam, Shalinee; Zewdie, Kidist; Bierut, Laura J.; Cavazos-Rehg, Patricia A.

2015-01-01

Background Dabbing involves heating marijuana extracts to a high temperature and inhaling the vapor. Little is known about this new method of using marijuana. YouTube, the most popular platform for sharing online videos, may be a go-to resource for individuals interested in learning about dabbing. Our objective was to explore the content of dabbing-related videos on YouTube. Methods We searched for dabbing related videos on YouTube using the search terms “dabbing” and “dabs” on January 22, 2015. For each term, videos were sorted by relevance and view count. A sample of 116 dabbing videos were viewed and coded for content. Results The 116 videos (published by 75 unique channels) had a total of 9,545,482 views. Most (76%) of the channels had a specific focus on marijuana and 23% were located in California. 89% of the videos showed at least one person dabbing, and 61% of these showed someone dabbing repeatedly. Most dabbers were male (67%) and many appeared to be >25 years old (42%). Approximately 34% of the videos contained a product review, 28% provided instructions on dabbing or other educational information, and 21% contained at least a brief cautionary message. Over half (54%) of the videos referenced medical marijuana, and only 20% of the videos had an age restriction. Conclusions Dabbing-related videos are easily found and can be readily viewed on YouTube. As marijuana use becomes more accepted by the general population, the popularity of dabbing-related videos could increase, potentially normalizing this potent form of marijuana use. PMID:26347408

Is video gaming, or video game addiction, associated with depression, academic achievement, heavy episodic drinking, or conduct problems?

PubMed

Brunborg, Geir Scott; Mentzoni, Rune Aune; Frøyland, Lars Roar

2014-03-01

While the relationships between video game use and negative consequences are debated, the relationships between video game addiction and negative consequences are fairly well established. However, previous studies suffer from methodological weaknesses that may have caused biased results. There is need for further investigation that benefits from the use of methods that avoid omitted variable bias. Two wave panel data was used from two surveys of 1,928 Norwegian adolescents aged 13 to 17 years. The surveys included measures of video game use, video game addiction, depression, heavy episodic drinking, academic achievement, and conduct problems. The data was analyzed using first-differencing, a regression method that is unbiased by time invariant individual factors. Video game addiction was related to depression, lower academic achievement, and conduct problems, but time spent on video games was not related to any of the studied negative outcomes. The findings were in line with a growing number of studies that have failed to find relationships between time spent on video games and negative outcomes. The current study is also consistent with previous studies in that video game addiction was related to other negative outcomes, but it made the added contribution that the relationships are unbiased by time invariant individual effects. However, future research should aim at establishing the temporal order of the supposed causal effects. Spending time playing video games does not involve negative consequences, but adolescents who experience problems related to video games are likely to also experience problems in other facets of life.

Automated quantitative gait analysis during overground locomotion in the rat: its application to spinal cord contusion and transection injuries.

PubMed

Hamers, F P; Lankhorst, A J; van Laar, T J; Veldhuis, W B; Gispen, W H

2001-02-01

Analysis of locomotion is an important tool in the study of peripheral and central nervous system damage. Most locomotor scoring systems in rodents are based either upon open field locomotion assessment, for example, the BBB score or upon foot print analysis. The former yields a semiquantitative description of locomotion as a whole, whereas the latter generates quantitative data on several selected gait parameters. In this paper, we describe the use of a newly developed gait analysis method that allows easy quantitation of a large number of locomotion parameters during walkway crossing. We were able to extract data on interlimb coordination, swing duration, paw print areas (total over stance, and at 20-msec time resolution), stride length, and base of support: Similar data can not be gathered by any single previously described method. We compare changes in gait parameters induced by two different models of spinal cord injury in rats, transection of the dorsal half of the spinal cord and spinal cord contusion injury induced by the NYU or MASCIS device. Although we applied this method to rats with spinal cord injury, the usefulness of this method is not limited to rats or to the investigation of spinal cord injuries alone.

Spatial Pyramid Covariance based Compact Video Code for Robust Face Retrieval in TV-series.

PubMed

Li, Yan; Wang, Ruiping; Cui, Zhen; Shan, Shiguang; Chen, Xilin

2016-10-10

We address the problem of face video retrieval in TV-series which searches video clips based on the presence of specific character, given one face track of his/her. This is tremendously challenging because on one hand, faces in TV-series are captured in largely uncontrolled conditions with complex appearance variations, and on the other hand retrieval task typically needs efficient representation with low time and space complexity. To handle this problem, we propose a compact and discriminative representation for the huge body of video data, named Compact Video Code (CVC). Our method first models the face track by its sample (i.e., frame) covariance matrix to capture the video data variations in a statistical manner. To incorporate discriminative information and obtain more compact video signature suitable for retrieval, the high-dimensional covariance representation is further encoded as a much lower-dimensional binary vector, which finally yields the proposed CVC. Specifically, each bit of the code, i.e., each dimension of the binary vector, is produced via supervised learning in a max margin framework, which aims to make a balance between the discriminability and stability of the code. Besides, we further extend the descriptive granularity of covariance matrix from traditional pixel-level to more general patchlevel, and proceed to propose a novel hierarchical video representation named Spatial Pyramid Covariance (SPC) along with a fast calculation method. Face retrieval experiments on two challenging TV-series video databases, i.e., the Big Bang Theory and Prison Break, demonstrate the competitiveness of the proposed CVC over state-of-the-art retrieval methods. In addition, as a general video matching algorithm, CVC is also evaluated in traditional video face recognition task on a standard Internet database, i.e., YouTube Celebrities, showing its quite promising performance by using an extremely compact code with only 128 bits.

A method of intentional movement estimation of oblique small-UAV videos stabilized based on homography model

NASA Astrophysics Data System (ADS)

Guo, Shiyi; Mai, Ying; Zhao, Hongying; Gao, Pengqi

2013-05-01

The airborne video streams of small-UAVs are commonly plagued with distractive jittery and shaking motions, disorienting rotations, noisy and distorted images and other unwanted movements. These problems collectively make it very difficult for observers to obtain useful information from the video. Due to the small payload of small-UAVs, it is a priority to improve the image quality by means of electronic image stabilization. But when small-UAV makes a turn, affected by the flight characteristics of it, the video is easy to become oblique. This brings a lot of difficulties to electronic image stabilization technology. Homography model performed well in the oblique image motion estimation, while bringing great challenges to intentional motion estimation. Therefore, in this paper, we focus on solve the problem of the video stabilized when small-UAVs banking and turning. We attend to the small-UAVs fly along with an arc of a fixed turning radius. For this reason, after a series of experimental analysis on the flight characteristics and the path how small-UAVs turned, we presented a new method to estimate the intentional motion in which the path of the frame center was used to fit the video moving track. Meanwhile, the image sequences dynamic mosaic was done to make up for the limited field of view. At last, the proposed algorithm was carried out and validated by actual airborne videos. The results show that the proposed method is effective to stabilize the oblique video of small-UAVs.

Video surveillance captures student hand hygiene behavior, reactivity to observation, and peer influence in Kenyan primary schools.

PubMed

Pickering, Amy J; Blum, Annalise G; Breiman, Robert F; Ram, Pavani K; Davis, Jennifer

2014-01-01

In-person structured observation is considered the best approach for measuring hand hygiene behavior, yet is expensive, time consuming, and may alter behavior. Video surveillance could be a useful tool for objectively monitoring hand hygiene behavior if validated against current methods. Student hand cleaning behavior was monitored with video surveillance and in-person structured observation, both simultaneously and separately, at four primary schools in urban Kenya over a study period of 8 weeks. Video surveillance and in-person observation captured similar rates of hand cleaning (absolute difference <5%, p = 0.74). Video surveillance documented higher hand cleaning rates (71%) when at least one other person was present at the hand cleaning station, compared to when a student was alone (48%; rate ratio  = 1.14 [95% CI 1.01-1.28]). Students increased hand cleaning rates during simultaneous video and in-person monitoring as compared to single-method monitoring, suggesting reactivity to each method of monitoring. This trend was documented at schools receiving a handwashing with soap intervention, but not at schools receiving a sanitizer intervention. Video surveillance of hand hygiene behavior yields results comparable to in-person observation among schools in a resource-constrained setting. Video surveillance also has certain advantages over in-person observation, including rapid data processing and the capability to capture new behavioral insights. Peer influence can significantly improve student hand cleaning behavior and, when possible, should be exploited in the design and implementation of school hand hygiene programs.

Transana Qualitative Video and Audio Analysis Software as a Tool for Teaching Intellectual Assessment Skills to Graduate Psychology Students

ERIC Educational Resources Information Center

Rush, S. Craig

2014-01-01

This article draws on the author's experience using qualitative video and audio analysis, most notably through use of the Transana qualitative video and audio analysis software program, as an alternative method for teaching IQ administration skills to students in a graduate psychology program. Qualitative video and audio analysis may be useful for…

Losing the Red Pen: Video Grading Feedback in Distance and Blended Learning Writing Courses

ERIC Educational Resources Information Center

Jones, Lisa Ann

2014-01-01

This paper will give a step-by-step demonstration on how to create MP4 files to video-grade undergraduate writing assignments. The process of using prepared rubrics to guide video and audio feedback will be presented and examples shown. This assessment method provides students with personalized video-feedback as a re-usable learning object. The…

How to Create Videos for Extension Education: An Innovative Five-Step Procedure

ERIC Educational Resources Information Center

Dev, Dipti A.; Blitch, Kimberly A.; Hatton-Bowers, Holly; Ramsay, Samantha; Garcia, Aileen S.

2018-01-01

Although the benefits of using video as a learning tool in Extension programs are well known, less is understood about effective methods for creating videos. We present a five-step procedure for developing educational videos that focus on evidence-based practices, and we provide practical examples from our use of the five steps in creating a video…

A new method for wireless video monitoring of bird nests

Treesearch

David I. King; Richard M. DeGraaf; Paul J. Champlin; Tracey B. Champlin

2001-01-01

Video monitoring of active bird nests is gaining popularity among researchers because it eliminates many of the biases associated with reliance on incidental observations of predation events or use of artificial nests, but the expense of video systems may be prohibitive. Also, the range and efficiency of current video monitoring systems may be limited by the need to...

Video-based noncooperative iris image segmentation.

PubMed

Du, Yingzi; Arslanturk, Emrah; Zhou, Zhi; Belcher, Craig

2011-02-01

In this paper, we propose a video-based noncooperative iris image segmentation scheme that incorporates a quality filter to quickly eliminate images without an eye, employs a coarse-to-fine segmentation scheme to improve the overall efficiency, uses a direct least squares fitting of ellipses method to model the deformed pupil and limbic boundaries, and develops a window gradient-based method to remove noise in the iris region. A remote iris acquisition system is set up to collect noncooperative iris video images. An objective method is used to quantitatively evaluate the accuracy of the segmentation results. The experimental results demonstrate the effectiveness of this method. The proposed method would make noncooperative iris recognition or iris surveillance possible.

Inter-view prediction of intra mode decision for high-efficiency video coding-based multiview video coding

NASA Astrophysics Data System (ADS)

da Silva, Thaísa Leal; Agostini, Luciano Volcan; da Silva Cruz, Luis A.

2014-05-01

Intra prediction is a very important tool in current video coding standards. High-efficiency video coding (HEVC) intra prediction presents relevant gains in encoding efficiency when compared to previous standards, but with a very important increase in the computational complexity since 33 directional angular modes must be evaluated. Motivated by this high complexity, this article presents a complexity reduction algorithm developed to reduce the HEVC intra mode decision complexity targeting multiview videos. The proposed algorithm presents an efficient fast intra prediction compliant with singleview and multiview video encoding. This fast solution defines a reduced subset of intra directions according to the video texture and it exploits the relationship between prediction units (PUs) of neighbor depth levels of the coding tree. This fast intra coding procedure is used to develop an inter-view prediction method, which exploits the relationship between the intra mode directions of adjacent views to further accelerate the intra prediction process in multiview video encoding applications. When compared to HEVC simulcast, our method achieves a complexity reduction of up to 47.77%, at the cost of an average BD-PSNR loss of 0.08 dB.

A web-based video annotation system for crowdsourcing surveillance videos

NASA Astrophysics Data System (ADS)

Gadgil, Neeraj J.; Tahboub, Khalid; Kirsh, David; Delp, Edward J.

2014-03-01

Video surveillance systems are of a great value to prevent threats and identify/investigate criminal activities. Manual analysis of a huge amount of video data from several cameras over a long period of time often becomes impracticable. The use of automatic detection methods can be challenging when the video contains many objects with complex motion and occlusions. Crowdsourcing has been proposed as an effective method for utilizing human intelligence to perform several tasks. Our system provides a platform for the annotation of surveillance video in an organized and controlled way. One can monitor a surveillance system using a set of tools such as training modules, roles and labels, task management. This system can be used in a real-time streaming mode to detect any potential threats or as an investigative tool to analyze past events. Annotators can annotate video contents assigned to them for suspicious activity or criminal acts. First responders are then able to view the collective annotations and receive email alerts about a newly reported incident. They can also keep track of the annotators' training performance, manage their activities and reward their success. By providing this system, the process of video analysis is made more efficient.

QUANTITATIVE STUDY OF CLINAL VARIATION IN Juniperus virginiana USING TERPENOID DATA*

PubMed Central

Flake, Robert H.; Rudloff, Ernst Von; Turner, B. L.

1969-01-01

Nine populations of Juniperus virginiana were sampled at approximately 150-mile intervals along a 1500-mile transect from northeastern Texas to Washington, D.C. Individual plants were examined for terpenoids by gas liquid chromatography and the resulting data analyzed by numerical classification methods using characters weighted according to their estimated variance in the natural populations. The results of the analysis show that these populations of J. virginiana cluster clinally from northeast to southwest, the more homogeneous populations occurring in the Appalachian region of North America; the more divergent populations found in progressively more distant regions, as measured along the transect from the northeast toward the southwest. No biochemical evidence could be found to support the hypothesis that hybridization with J. ashei might be causing this variability, as had been widely supposed previously. PMID:16591792

Neural Basis of Video Gaming: A Systematic Review

PubMed Central

Palaus, Marc; Marron, Elena M.; Viejo-Sobera, Raquel; Redolar-Ripoll, Diego

2017-01-01

Background: Video gaming is an increasingly popular activity in contemporary society, especially among young people, and video games are increasing in popularity not only as a research tool but also as a field of study. Many studies have focused on the neural and behavioral effects of video games, providing a great deal of video game derived brain correlates in recent decades. There is a great amount of information, obtained through a myriad of methods, providing neural correlates of video games. Objectives: We aim to understand the relationship between the use of video games and their neural correlates, taking into account the whole variety of cognitive factors that they encompass. Methods: A systematic review was conducted using standardized search operators that included the presence of video games and neuro-imaging techniques or references to structural or functional brain changes. Separate categories were made for studies featuring Internet Gaming Disorder and studies focused on the violent content of video games. Results: A total of 116 articles were considered for the final selection. One hundred provided functional data and 22 measured structural brain changes. One-third of the studies covered video game addiction, and 14% focused on video game related violence. Conclusions: Despite the innate heterogeneity of the field of study, it has been possible to establish a series of links between the neural and cognitive aspects, particularly regarding attention, cognitive control, visuospatial skills, cognitive workload, and reward processing. However, many aspects could be improved. The lack of standardization in the different aspects of video game related research, such as the participants' characteristics, the features of each video game genre and the diverse study goals could contribute to discrepancies in many related studies. PMID:28588464

Neural Basis of Video Gaming: A Systematic Review.

PubMed

Palaus, Marc; Marron, Elena M; Viejo-Sobera, Raquel; Redolar-Ripoll, Diego

2017-01-01

Background: Video gaming is an increasingly popular activity in contemporary society, especially among young people, and video games are increasing in popularity not only as a research tool but also as a field of study. Many studies have focused on the neural and behavioral effects of video games, providing a great deal of video game derived brain correlates in recent decades. There is a great amount of information, obtained through a myriad of methods, providing neural correlates of video games. Objectives: We aim to understand the relationship between the use of video games and their neural correlates, taking into account the whole variety of cognitive factors that they encompass. Methods: A systematic review was conducted using standardized search operators that included the presence of video games and neuro-imaging techniques or references to structural or functional brain changes. Separate categories were made for studies featuring Internet Gaming Disorder and studies focused on the violent content of video games. Results: A total of 116 articles were considered for the final selection. One hundred provided functional data and 22 measured structural brain changes. One-third of the studies covered video game addiction, and 14% focused on video game related violence. Conclusions: Despite the innate heterogeneity of the field of study, it has been possible to establish a series of links between the neural and cognitive aspects, particularly regarding attention, cognitive control, visuospatial skills, cognitive workload, and reward processing. However, many aspects could be improved. The lack of standardization in the different aspects of video game related research, such as the participants' characteristics, the features of each video game genre and the diverse study goals could contribute to discrepancies in many related studies.

Low-complexity video encoding method for wireless image transmission in capsule endoscope.

PubMed

Takizawa, Kenichi; Hamaguchi, Kiyoshi

2010-01-01

This paper presents a low-complexity video encoding method applicable for wireless image transmission in capsule endoscopes. This encoding method is based on Wyner-Ziv theory, in which side information available at a transmitter is treated as side information at its receiver. Therefore complex processes in video encoding, such as estimation of the motion vector, are moved to the receiver side, which has a larger-capacity battery. As a result, the encoding process is only to decimate coded original data through channel coding. We provide a performance evaluation for a low-density parity check (LDPC) coding method in the AWGN channel.

Dual-tracer method to estimate coral reef response to a plume of chemically modified seawater

NASA Astrophysics Data System (ADS)

Maclaren, J. K.; Caldeira, K.

2013-12-01

We present a new method, based on measurement of seawater samples, to estimate the response of a reef ecosystem to a plume of an additive (for example, a nutrient or other chemical). In the natural environment, where there may be natural variability in concentrations, it can be difficult to distinguish between changes in concentrations that would occur naturally and changes in concentrations that result from a chemical addition. Furthermore, in the unconfined natural environment, chemically modified water can mix with waters that have not been modified, making it difficult to distinguish between effects of dilution and effects of chemical fluxes or transformations. We present a dual-tracer method that extracts signals from observations that may be affected by both natural variability and dilution. In this dual-tracer method, a substance (in our example case, alkalinity) is added to the water in known proportion to a passive conservative tracer (in our example case, Rhodamine WT dye). The resulting plume of seawater is allowed to flow over the study site. Two transects are drawn across the plume at the front and back of the study site. If, in our example, alkalinity is plotted as a function of dye concentration for the front transect, the slope of the resulting mixing line is the ratio of alkalinity to dye in the added fluid. If a similar mixing line is measured and calculated for the back transect, the slope of this mixing line will indicate the amount of added alkalinity that remains in the water flowing out of the study site per unit of added dye. The ratio of the front and back slopes indicates the fraction of added alkalinity that was taken up by the reef. The method is demonstrated in an experiment performed on One Tree Reef (Queensland, Australia) aimed at showing that ocean acidification is already affecting coral reef growth. In an effort to chemically reverse some of the changes to seawater chemistry that have occurred over the past 200 years, we added sodium hydroxide to increase alkalinity in the plume and controlled for dilution with Rhodamine WT dye. Preliminary data will be presented and analyzed using the approach described above.

Characterization of bulbospongiosus muscle reflexes activated by urethral distension in male rats.

PubMed

Tanahashi, Masayuki; Karicheti, Venkateswarlu; Thor, Karl B; Marson, Lesley

2012-10-01

The urethrogenital reflex (UGR) is used as a surrogate model of the autonomic and somatic nerve and muscle activity that accompanies ejaculation. The UGR is evoked by distension of the urethra and activation of penile afferents. The current study compares two methods of elevating urethral intraluminal pressure in spinalized, anesthetized male Sprague-Dawley rats (n = 60). The first method, penile extension UGR, involves extracting the penis from the foreskin, so that urethral pressure rises due to a natural anatomical flexure in the penis. The second method, penile clamping UGR, involves penile extension UGR with the addition of clamping of the glans penis. Groups of animals were prepared that either received no additional treatment, surgical shams, or received bilateral nerve cuts (4 nerve cut groups): either the pudendal sensory nerve branch (SbPN), the pelvic nerves, the hypogastric nerves, or all three nerves. Penile clamping UGR was characterized by multiple bursts, monitored by electromyography (EMG) of the bulbospongiosus muscle (BSM) accompanied by elevations in urethral pressure. The penile clamping UGR activity declined across multiple trials and eventually resulted in only a single BSM burst, indicating desensitization. In contrast, the penile extension UGR, without penile clamping, evoked only a single BSM EMG burst that showed no desensitization. Thus, the UGR is composed of two BSM patterns: an initial single burst, termed urethrobulbospongiosus (UBS) reflex and a subsequent multiple bursting pattern (termed ejaculation-like response, ELR) that was only induced with penile clamping urethral occlusion. Transection of the SbPN eliminated the ELR in the penile clamping model, but the single UBS reflex remained in both the clamping and extension models. Pelvic nerve (PelN) transection increased the threshold for inducing BSM activation with both methods of occlusion but actually unmasked an ELR in the penile extension method. Hypogastric nerve (HgN) cuts did not significantly alter any parameter. Transection of all three nerves eliminated BSM activation completely. In conclusion, penile clamping occlusion recruits penile and urethral primary afferent fibers that are necessary for an ELR. Urethral distension without significant penile afferent activation recruits urethral primary afferent fibers carried in either the pelvic or pudendal nerve that are necessary for the single-burst UBS reflex.

Changes in the colon microbiota and intestinal cytokine gene expression following minimal intestinal surgery

PubMed Central

Lapthorne, Susan; Bines, Julie E; Fouhy, Fiona; Dellios, Nicole L; Wilson, Guineva; Thomas, Sarah L; Scurr, Michelle; Stanton, Catherine; Cotter, Paul D; Pereira-Fantini, Prue M

2015-01-01

AIM: To investigate the impact of minor abdominal surgery on the caecal microbial population and on markers of gut inflammation. METHODS: Four week old piglets were randomly allocated to a no-surgery “control” group (n = 6) or a “transection surgery” group (n = 5). During the transection surgery procedure, a conventional midline incision of the lower abdominal wall was made and the small intestine was transected at a site 225 cm proximal to the ileocaecal valve, a 2 cm segment was removed and the intestine was re-anastomosed. Piglets received a polymeric infant formula diet throughout the study period and were sacrificed at two weeks post-surgery. Clinical outcomes including weight, stool consistency and presence of stool fat globules were monitored. High throughput DNA sequencing of colonic content was used to detect surgery-related disturbances in microbial composition at phylum, family and genus level. Diversity and richness estimates were calculated for the control and minor surgery groups. As disturbances in the gut microbial community are linked to inflammation we compared the gene expression of key inflammatory cytokines (TNF, IL1B, IL18, IL12, IL8, IL6 and IL10) in ileum, terminal ileum and colon mucosal extracts obtained from control and abdominal surgery groups at two weeks post-surgery. RESULTS: Changes in the relative abundance of bacterial species at family and genus level were confined to bacterial members of the Proteobacteria and Bacteroidetes phyla. Family level compositional shifts included a reduction in the relative abundance of Enterobacteriaceae (22.95 ± 5.27 vs 2.07 ± 0.72, P < 0.01), Bacteroidaceae (2.54 ± 0.56 vs 0.86 ± 0.43, P < 0.05) and Rhodospirillaceae (0.40 ± 0.14 vs 0.00 ± 0.00, P < 0.05) following transection surgery. Similarly, at the genus level, changes associated with transection surgery were restricted to members of the Proteobacteria and Bacteroidetes phyla and included decreased relative abundance of Enterobacteriaceae (29.20 ± 6.74 vs 2.88 ± 1.08, P < 0.01), Alistipes (4.82 ± 1.73 vs 0.18 ± 0.13, P < 0.05) and Thalassospira (0.53 ± 0.19 vs 0.00 ± 0.00, P < 0.05). Surgery-associated microbial dysbiosis was accompanied by increased gene expression of markers of inflammation. Within the ileum IL6 expression was decreased (4.46 ± 1.60 vs 0.24 ± 0.06, P < 0.05) following transection surgery. In the terminal ileum, gene expression of TNF was decreased (1.51 ± 0.13 vs 0.80 ± 0.16, P < 0.01) and IL18 (1.21 ± 0.18 vs 2.13 ± 0.24, P < 0.01), IL12 (1.04 ± 0.16 vs 1.82 ± 0.32, P < 0.05) and IL10 (1.04 ± 0.06 vs 1.43 ± 0.09, P < 0.01) gene expression increased following transection surgery. Within the colon, IL12 (0.72 ± 0.13 vs 1.78 ± 0.28, P < 0.01) and IL10 (0.98 ± 0.02 vs 1.95 ± 0.14, P < 0.01) gene expression were increased following transection surgery. CONCLUSION: This study suggests that minor abdominal surgery in infants, results in long-term alteration of the colonic microbial composition and persistent gastrointestinal inflammation. PMID:25892864

Misleading Health-Related Information Promoted Through Video-Based Social Media: Anorexia on YouTube

PubMed Central

Li, Yu-Chuan; Crain, Steven; Hsu, Min-Huei; Wang, Yao-Chin; Khandregzen, Dorjsuren; Chuluunbaatar, Enkhzaya; Nguyen, Phung Anh

2013-01-01

Introduction The amount of information being uploaded onto social video platforms, such as YouTube, Vimeo, and Veoh, continues to spiral, making it increasingly difficult to discern reliable health information from misleading content. There are thousands of YouTube videos promoting misleading information about anorexia (eg, anorexia as a healthy lifestyle). Objective The aim of this study was to investigate anorexia-related misinformation disseminated through YouTube videos. Methods We retrieved YouTube videos related to anorexia using the keywords anorexia, anorexia nervosa, proana, and thinspo on October 10, 2011.Three doctors reviewed 140 videos with approximately 11 hours of video content, classifying them as informative, pro-anorexia, or others. By informative we mean content describing the health consequences of anorexia and advice on how to recover from it; by pro-anorexia we mean videos promoting anorexia as a fashion, a source of beauty, and that share tips and methods for becoming and remaining anorexic. The 40 most-viewed videos (20 informative and 20 pro-anorexia videos) were assessed to gauge viewer behavior. Results The interrater agreement of classification was moderate (Fleiss’ kappa=0.5), with 29.3% (n=41) being rated as pro-anorexia, 55.7% (n=78) as informative, and 15.0% (n=21) as others. Pro-anorexia videos were favored 3 times more than informative videos (odds ratio [OR] 3.3, 95% CI 3.3-3.4, P<.001). Conclusions Pro-anorexia information was identified in 29.3% of anorexia-related videos. Pro-anorexia videos are less common than informative videos; however, in proportional terms, pro-anorexia content is more highly favored and rated by its viewers. Efforts should focus on raising awareness, particularly among teenagers, about the trustworthiness of online information about beauty and healthy lifestyles. Health authorities producing videos to combat anorexia should consider involving celebrities and models to reach a wider audience. More research is needed to study the characteristics of pro-anorexia videos in order to develop algorithms that will automatically detect and filter those videos before they become popular. PMID:23406655

Deep linear autoencoder and patch clustering-based unified one-dimensional coding of image and video

NASA Astrophysics Data System (ADS)

Li, Honggui

2017-09-01

This paper proposes a unified one-dimensional (1-D) coding framework of image and video, which depends on deep learning neural network and image patch clustering. First, an improved K-means clustering algorithm for image patches is employed to obtain the compact inputs of deep artificial neural network. Second, for the purpose of best reconstructing original image patches, deep linear autoencoder (DLA), a linear version of the classical deep nonlinear autoencoder, is introduced to achieve the 1-D representation of image blocks. Under the circumstances of 1-D representation, DLA is capable of attaining zero reconstruction error, which is impossible for the classical nonlinear dimensionality reduction methods. Third, a unified 1-D coding infrastructure for image, intraframe, interframe, multiview video, three-dimensional (3-D) video, and multiview 3-D video is built by incorporating different categories of videos into the inputs of patch clustering algorithm. Finally, it is shown in the results of simulation experiments that the proposed methods can simultaneously gain higher compression ratio and peak signal-to-noise ratio than those of the state-of-the-art methods in the situation of low bitrate transmission.

Detection and tracking of gas plumes in LWIR hyperspectral video sequence data

NASA Astrophysics Data System (ADS)

Gerhart, Torin; Sunu, Justin; Lieu, Lauren; Merkurjev, Ekaterina; Chang, Jen-Mei; Gilles, Jérôme; Bertozzi, Andrea L.

2013-05-01

Automated detection of chemical plumes presents a segmentation challenge. The segmentation problem for gas plumes is difficult due to the diffusive nature of the cloud. The advantage of considering hyperspectral images in the gas plume detection problem over the conventional RGB imagery is the presence of non-visual data, allowing for a richer representation of information. In this paper we present an effective method of visualizing hyperspectral video sequences containing chemical plumes and investigate the effectiveness of segmentation techniques on these post-processed videos. Our approach uses a combination of dimension reduction and histogram equalization to prepare the hyperspectral videos for segmentation. First, Principal Components Analysis (PCA) is used to reduce the dimension of the entire video sequence. This is done by projecting each pixel onto the first few Principal Components resulting in a type of spectral filter. Next, a Midway method for histogram equalization is used. These methods redistribute the intensity values in order to reduce icker between frames. This properly prepares these high-dimensional video sequences for more traditional segmentation techniques. We compare the ability of various clustering techniques to properly segment the chemical plume. These include K-means, spectral clustering, and the Ginzburg-Landau functional.

A simple video-based timing system for on-ice team testing in ice hockey: a technical report.

PubMed

Larson, David P; Noonan, Benjamin C

2014-09-01

The purpose of this study was to describe and evaluate a newly developed on-ice timing system for team evaluation in the sport of ice hockey. We hypothesized that this new, simple, inexpensive, timing system would prove to be highly accurate and reliable. Six adult subjects (age 30.4 ± 6.2 years) performed on ice tests of acceleration and conditioning. The performance times of the subjects were recorded using a handheld stopwatch, photocell, and high-speed (240 frames per second) video. These results were then compared to allow for accuracy calculations of the stopwatch and video as compared with filtered photocell timing that was used as the "gold standard." Accuracy was evaluated using maximal differences, typical error/coefficient of variation (CV), and intraclass correlation coefficients (ICCs) between the timing methods. The reliability of the video method was evaluated using the same variables in a test-retest analysis both within and between evaluators. The video timing method proved to be both highly accurate (ICC: 0.96-0.99 and CV: 0.1-0.6% as compared with the photocell method) and reliable (ICC and CV within and between evaluators: 0.99 and 0.08%, respectively). This video-based timing method provides a very rapid means of collecting a high volume of very accurate and reliable on-ice measures of skating speed and conditioning, and can easily be adapted to other testing surfaces and parameters.

Live lecture versus video podcast in undergraduate medical education: A randomised controlled trial.

PubMed

Schreiber, Benjamin E; Fukuta, Junaid; Gordon, Fabiana

2010-10-08

Information technology is finding an increasing role in the training of medical students. We compared information recall and student experience and preference after live lectures and video podcasts in undergraduate medical education. We performed a crossover randomised controlled trial. 100 students were randomised to live lecture or video podcast for one clinical topic. Live lectures were given by the same instructor as the narrator of the video podcasts. The video podcasts comprised Powerpoint™ slides narrated using the same script as the lecture. They were then switched to the other group for a second clinical topic. Knowledge was assessed using multiple choice questions and qualitative information was collected using a questionnaire. No significant difference was found on multiple choice questioning immediately after the session. The subjects enjoyed the convenience of the video podcast and the ability to stop, review and repeat it, but found it less engaging as a teaching method. They expressed a clear preference for the live lecture format. We suggest that video podcasts are not ready to replace traditional teaching methods, but may have an important role in reinforcing learning and aiding revision.

Classification of Birds and Bats Using Flight Tracks

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

Cullinan, Valerie I.; Matzner, Shari; Duberstein, Corey A.

Classification of birds and bats that use areas targeted for offshore wind farm development and the inference of their behavior is essential to evaluating the potential effects of development. The current approach to assessing the number and distribution of birds at sea involves transect surveys using trained individuals in boats or airplanes or using high-resolution imagery. These approaches are costly and have safety concerns. Based on a limited annotated library extracted from a single-camera thermal video, we provide a framework for building models that classify birds and bats and their associated behaviors. As an example, we developed a discriminant modelmore » for theoretical flight paths and applied it to data (N = 64 tracks) extracted from 5-min video clips. The agreement between model- and observer-classified path types was initially only 41%, but it increased to 73% when small-scale jitter was censored and path types were combined. Classification of 46 tracks of bats, swallows, gulls, and terns on average was 82% accurate, based on a jackknife cross-validation. Model classification of bats and terns (N = 4 and 2, respectively) was 94% and 91% correct, respectively; however, the variance associated with the tracks from these targets is poorly estimated. Model classification of gulls and swallows (N ≥ 18) was on average 73% and 85% correct, respectively. The models developed here should be considered preliminary because they are based on a small data set both in terms of the numbers of species and the identified flight tracks. Future classification models would be greatly improved by including a measure of distance between the camera and the target.« less

Text Detection, Tracking and Recognition in Video: A Comprehensive Survey.

PubMed

Yin, Xu-Cheng; Zuo, Ze-Yu; Tian, Shu; Liu, Cheng-Lin

2016-04-14

Intelligent analysis of video data is currently in wide demand because video is a major source of sensory data in our lives. Text is a prominent and direct source of information in video, while recent surveys of text detection and recognition in imagery [1], [2] focus mainly on text extraction from scene images. Here, this paper presents a comprehensive survey of text detection, tracking and recognition in video with three major contributions. First, a generic framework is proposed for video text extraction that uniformly describes detection, tracking, recognition, and their relations and interactions. Second, within this framework, a variety of methods, systems and evaluation protocols of video text extraction are summarized, compared, and analyzed. Existing text tracking techniques, tracking based detection and recognition techniques are specifically highlighted. Third, related applications, prominent challenges, and future directions for video text extraction (especially from scene videos and web videos) are also thoroughly discussed.

Mesoscale variability observed in the Northern Adriatic in autumn 2016

NASA Astrophysics Data System (ADS)

Pasaric, Zoran; Iva, Medjugorac; Nastjenka, Supic; Tamara, Djakovac; Mirko, Orlic

2017-04-01

Quasi-synoptic measurements of hydrographic properties were performed in the Northern Adriatic along the transect extending from Rovinj to the Po River mouth in an approximately east-west direction. The depth along the transect slowly varies between 30 and 40 m. Three one-day cruises were conducted, the first on 12 Nov, the second on 18 Nov, and the third on 25 Nov 2016. During the first and the third cruise the sampling was done with a CTD probe lowered from the surface to the bottom, at eleven stations placed nearly equidistantly along the transect. Average distance between the stations was 6 km. The second cruise was conducted with a towed yo-yo profiler equipped with the CTD probe and continuously undulating between the surface and some 4 m above the bottom. With roughly three undulations per kilometer, horizontal resolution along the transect was about 200 m. The data suggest that three processes occurred during the cruises: 1) surface cooling and related vertical mixing, 2) intrusion of high-salinity waters into the western part of the transect, and 3) propagation of a mesoscale formation in a westward direction. The existence and propagation of the mesoscale feature is supported by a simple analytical model of topographic Rossby waves. By assuming that the bottom varies linearly in the direction perpendicular to the transect, the propagation speed of O(1 km/day) is obtained - in agreement with the observations.

Environmental variation, vegetation distribution, carbon dynamics and water/energy exchange at high latitudes

USGS Publications Warehouse

McGuire, A.D.; Wirth, C.; Apps, M.; Beringer, J.; Clein, J.; Epstein, H.; Kicklighter, D.W.; Bhatti, J.; Chapin, F. S.; De Groot, B.; Efremov, D.; Eugster, W.; Fukuda, M.; Gower, T.; Hinzman, L.; Huntley, B.; Jia, G.J.; Kasischke, E.; Melillo, J.; Romanovsky, V.; Shvidenko, A.; Vaganov, E.; Walker, D.

2002-01-01

The responses of high latitude ecosystems to global change involve complex interactions among environmental variables, vegetation distribution, carbon dynamics, and water and energy exchange. These responses may have important consequences for the earth system. In this study, we evaluated how vegetation distribution, carbon stocks and turnover, and water and energy exchange are related to environmental variation spanned by the network of the IGBP high latitude transects. While the most notable feature of the high latitude transects is that they generally span temperature gradients from southern to northern latitudes, there are substantial differences in temperature among the transects. Also, along each transect temperature co-varies with precipitation and photosynthetically active radiation, which are also variable among the transects. Both climate and disturbance interact to influence latitudinal patterns of vegetation and soil carbon storage among the transects, and vegetation distribution appears to interact with climate to determine exchanges of heat and moisture in high latitudes. Despite limitations imposed by the data we assembled, the analyses in this study have taken an important step toward clarifying the complexity of interactions among environmental variables, vegetation distribution, carbon stocks and turnover, and water and energy exchange in high latitude regions. This study reveals the need to conduct coordinated global change studies in high latitudes to further elucidate how interactions among climate, disturbance, and vegetation distribution influence carbon dynamics and water and energy exchange in high latitudes.

Expression of the repulsive guidance molecule RGM and it receptor Neogenin after spinal cord injury in sea lamprey

PubMed Central

Shifman, Michael I.; Yumul, Rae Eden; Laramore, Cindy; Selzer, Michael E.

2009-01-01

The sea lamprey recovers normal-appearing locomotion after spinal cord transection and its spinal axons regenerate selectively in their correct paths. However, among identified reticulospinal neurons some are consistently bad regenerators and only about 50% of severed reticulospinal axons regenerate through the site of injury. We previously suggested (Shifman and Selzer, 2000) that selective chemorepulsion might explain why some neurons are bad regenerators and others not. To explore the role of additional chemorepulsive axonal guidance molecules during regeneration, we examined the expression of the repulsive guidance molecule (RGM) and its receptor neogenin by in situ hybridization and quantitative PCR. RGM mRNA was expressed in the spinal cord, primarily in neurons of the lateral gray matter and in dorsal cells. Following spinal cord transection, RGM message was downregulated in neurons close (within 10 mm) to the transection at 2 and 4 weeks, although it was upregulated in reactive microglia at 2 weeks post-transection. Neogenin mRNA expression was unchanged in the brainstem after spinal cord transection, and among the identified reticulospinal neurons, was detected only in “bad regenerators, Neurons that are known to regenerate well never expressed neogenin. The downregulation of RGM expression in neurons near the transection may increase the probability that regenerating axons will regenerate through the site of injury and entered caudal spinal cord. PMID:19268666

Influence of audio triggered emotional attention on video perception

NASA Astrophysics Data System (ADS)

Torres, Freddy; Kalva, Hari

2014-02-01

Perceptual video coding methods attempt to improve compression efficiency by discarding visual information not perceived by end users. Most of the current approaches for perceptual video coding only use visual features ignoring the auditory component. Many psychophysical studies have demonstrated that auditory stimuli affects our visual perception. In this paper we present our study of audio triggered emotional attention and it's applicability to perceptual video coding. Experiments with movie clips show that the reaction time to detect video compression artifacts was longer when video was presented with the audio information. The results reported are statistically significant with p=0.024.

Photometric Calibration of Consumer Video Cameras

NASA Technical Reports Server (NTRS)

Suggs, Robert; Swift, Wesley, Jr.

2007-01-01

Equipment and techniques have been developed to implement a method of photometric calibration of consumer video cameras for imaging of objects that are sufficiently narrow or sufficiently distant to be optically equivalent to point or line sources. Heretofore, it has been difficult to calibrate consumer video cameras, especially in cases of image saturation, because they exhibit nonlinear responses with dynamic ranges much smaller than those of scientific-grade video cameras. The present method not only takes this difficulty in stride but also makes it possible to extend effective dynamic ranges to several powers of ten beyond saturation levels. The method will likely be primarily useful in astronomical photometry. There are also potential commercial applications in medical and industrial imaging of point or line sources in the presence of saturation.This development was prompted by the need to measure brightnesses of debris in amateur video images of the breakup of the Space Shuttle Columbia. The purpose of these measurements is to use the brightness values to estimate relative masses of debris objects. In most of the images, the brightness of the main body of Columbia was found to exceed the dynamic ranges of the cameras. A similar problem arose a few years ago in the analysis of video images of Leonid meteors. The present method is a refined version of the calibration method developed to solve the Leonid calibration problem. In this method, one performs an endto- end calibration of the entire imaging system, including not only the imaging optics and imaging photodetector array but also analog tape recording and playback equipment (if used) and any frame grabber or other analog-to-digital converter (if used). To automatically incorporate the effects of nonlinearity and any other distortions into the calibration, the calibration images are processed in precisely the same manner as are the images of meteors, space-shuttle debris, or other objects that one seeks to analyze. The light source used to generate the calibration images is an artificial variable star comprising a Newtonian collimator illuminated by a light source modulated by a rotating variable neutral- density filter. This source acts as a point source, the brightness of which varies at a known rate. A video camera to be calibrated is aimed at this source. Fixed neutral-density filters are inserted in or removed from the light path as needed to make the video image of the source appear to fluctuate between dark and saturated bright. The resulting video-image data are analyzed by use of custom software that determines the integrated signal in each video frame and determines the system response curve (measured output signal versus input brightness). These determinations constitute the calibration, which is thereafter used in automatic, frame-by-frame processing of the data from the video images to be analyzed.

A field experiment and numerical modeling of a tracer at a gravel beach in Prince William Sound, Alaska

NASA Astrophysics Data System (ADS)

Guo, Qiaona; Li, Hailong; Boufadel, Michel C.; Liu, Jin

2014-12-01

Oil from the 1989 Exxon Valdez oil spill persists in many gravel beaches in Prince William Sound (Alaska, USA), despite great remedial efforts. A tracer study using lithium at a gravel beach on Knight Island, Prince William Sound, during the summer of 2008 is reported. The tracer injection and transport along a transect were simulated using the two-dimensional numerical model MARUN. Model results successfully reproduced the tracer concentrations observed at wells along the transect. A sensitivity analysis revealed that the estimated parameters are well determined. The simulated spatial distribution of tracer indicated that nutrients applied along the transect for bioremediation purposes would be washed to the sea very quickly (within a semi-diurnal tidal cycle) by virtue of the combination of the two-layered beach structure, the tidal fluctuation and the freshwater flow from inland. Thus, pore-water samples in the transect were found to be clean due to factors other than bioremediation. This may explain why the oil did not persist within the transect.

Consequences of Neurite Transection In Vitro

PubMed Central

Cengiz, Nurettin; Erdoğan, Ender; Him, Aydın; Oğuz, Elif Kaval

2012-01-01

Abstract In order to quantify degenerative and regenerative changes and analyze the contribution of multiple factors to the outcome after neurite transection, we cultured adult mouse dorsal root ganglion neurons, and with a precise laser beam, we transected the nerve fibers they extended. Cell preparations were continuously visualized for 24 h with time-lapse microscopy. More distal cuts caused a more elongated field of degeneration, while thicker neurites degenerated faster than thinner ones. Transected neurites degenerated more if the uncut neurites of the same neuron simultaneously degenerated. If any of these uncut processes regenerated, the transected neurites underwent less degeneration. Regeneration of neurites was limited to distal cuts. Unipolar neurons had shorter regeneration than multipolar ones. Branching slowed the regenerative process, while simultaneous degeneration of uncut neurites increased it. Proximal lesions, small neuronal size, and extensive and rapid neurite degeneration were predictive of death of an injured neuron, which typically displayed necrotic rather than apoptotic form. In conclusion, this in vitro model proved useful in unmasking many new aspects and correlates of mechanically-induced neurite injury. PMID:20121423

Detection of sea otters in boat-based surveys of Prince William Sound, Alaska. Marine mammal study 6-19. Exxon Valdez oil spill state/federal natural resource damage assessment final report

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

Udevitz, M.S.; Bodkin, J.L.; Costa, D.P.

1995-05-01

Boat-based surveys were used to monitor the Prince William Sound sea otter population before and after the Exxon Valdez oil spill. Population and loss estimates could be obtained from these surveys by direct expansion from the counts in the surveyed transects under the assumption that all otters in those transects were observed. The authors conducted a pilot study using ground-based observers in conjunction with the August 1990 survey of marine mammals and birds to investigate the validity of this assumption. The proportion of otters detected by boat crews was estimated by comparing boat and ground-based observations on 22 segments ofmore » shoreline transects. Overall, the authors estimated that only 70% of the otters in surveyed shoreline transects were detected by the boat crews. These results suggest that unadjusted expansions of boat survey transect counts will underestimate sea otter population size and that loss estimates based on comparisons of unadjusted population estimates will be biased.« less

Video Skimming and Characterization through the Combination of Image and Language Understanding Techniques

NASA Technical Reports Server (NTRS)

Smith, Michael A.; Kanade, Takeo

1997-01-01

Digital video is rapidly becoming important for education, entertainment, and a host of multimedia applications. With the size of the video collections growing to thousands of hours, technology is needed to effectively browse segments in a short time without losing the content of the video. We propose a method to extract the significant audio and video information and create a "skim" video which represents a very short synopsis of the original. The goal of this work is to show the utility of integrating language and image understanding techniques for video skimming by extraction of significant information, such as specific objects, audio keywords and relevant video structure. The resulting skim video is much shorter, where compaction is as high as 20:1, and yet retains the essential content of the original segment.

Automatic and user-centric approaches to video summary evaluation

NASA Astrophysics Data System (ADS)

Taskiran, Cuneyt M.; Bentley, Frank

2007-01-01

Automatic video summarization has become an active research topic in content-based video processing. However, not much emphasis has been placed on developing rigorous summary evaluation methods and developing summarization systems based on a clear understanding of user needs, obtained through user centered design. In this paper we address these two topics and propose an automatic video summary evaluation algorithm adapted from teh text summarization domain.

MAREANO: The national seafloor mapping programme of Norway - providing new knowledge for making informed management decisions

NASA Astrophysics Data System (ADS)

Thorsnes, T.; Bjarnadóttir, L. R.

2017-12-01

MAREANO (Marine AREA database for NOrwegian waters) is a state funded programme that has been mapping the seabed in Norwegian waters since 2005. Core datasets include detailed bathymetric data, video transect data and physical samples of the seabed. Integrated knowledge of the geology, habitats and the environmental status of the seabed is gained from the combined datasets and all results are presented on www.mareano.no. The results from MAREANO serve as a baseline of scientific information for decision-makers and which is actively used by ocean management agencies. Since 2005 the programme has grown and matured a great deal. Funding has increased twentyfold (now about 13 mill. USD), and the size of seabed mapped is now tenfold (about 22000 km2 annually). With this expansion the programme has evolved a more complex structure, regulating its activities more strictly and adhering to long-term plans. During this time the number of products has also increased, and so has the need for reviewing and improving methods. In 2015 MAREANO prepared a comprehensive report which documented and evaluated current methods and reviewed sampling/mapping standards based on management needs. Whilst the methods adopted by MAREANO to date have largely proved effective, several recent advances in technology within the various fields of seabed mapping offer great potential for improvements. Since 2014 MAREANO has been testing out some of this new technology such as acquisition of seabed data with improved resolution and autonomy in data collection, using AUVs equipped with synthetic aperture sonar and ROVs with underwater hyperspectral-sensors. Recently, MAREANO scientists have also been exploring new, more automated methods for data interpretation, classification and modelling. Preliminary results are promising and these new methods are expected to help to streamline the map production workflow in the future, thereby reducing production costs, while making even better maps that are both reproducible and more statistically robust. With its vast experience within seafloor mapping, MAREANO strives to prioritize dissemination of results through multiple channels, nationally and internationally. Currently MAREANO is also reaching out to the global community through the MAREAGLO initiative in order to share the MAREANO method.

User-oriented summary extraction for soccer video based on multimodal analysis

NASA Astrophysics Data System (ADS)

Liu, Huayong; Jiang, Shanshan; He, Tingting

2011-11-01

An advanced user-oriented summary extraction method for soccer video is proposed in this work. Firstly, an algorithm of user-oriented summary extraction for soccer video is introduced. A novel approach that integrates multimodal analysis, such as extraction and analysis of the stadium features, moving object features, audio features and text features is introduced. By these features the semantic of the soccer video and the highlight mode are obtained. Then we can find the highlight position and put them together by highlight degrees to obtain the video summary. The experimental results for sports video of world cup soccer games indicate that multimodal analysis is effective for soccer video browsing and retrieval.

A novel key-frame extraction approach for both video summary and video index.

PubMed

Lei, Shaoshuai; Xie, Gang; Yan, Gaowei

2014-01-01

Existing key-frame extraction methods are basically video summary oriented; yet the index task of key-frames is ignored. This paper presents a novel key-frame extraction approach which can be available for both video summary and video index. First a dynamic distance separability algorithm is advanced to divide a shot into subshots based on semantic structure, and then appropriate key-frames are extracted in each subshot by SVD decomposition. Finally, three evaluation indicators are proposed to evaluate the performance of the new approach. Experimental results show that the proposed approach achieves good semantic structure for semantics-based video index and meanwhile produces video summary consistent with human perception.

Error-free holographic frames encryption with CA pixel-permutation encoding algorithm

NASA Astrophysics Data System (ADS)

Li, Xiaowei; Xiao, Dan; Wang, Qiong-Hua

2018-01-01

The security of video data is necessary in network security transmission hence cryptography is technique to make video data secure and unreadable to unauthorized users. In this paper, we propose a holographic frames encryption technique based on the cellular automata (CA) pixel-permutation encoding algorithm. The concise pixel-permutation algorithm is used to address the drawbacks of the traditional CA encoding methods. The effectiveness of the proposed video encoding method is demonstrated by simulation examples.

A focus group study of the use of video-recorded simulated objective structured clinical examinations in nurse practitioner education.

PubMed

Barratt, Julian

2010-05-01

The objective structured clinical examination (OSCE) is a common method of clinical skills assessment used for advanced nurse practitioner students across the United Kingdom. The purpose of an advanced nursing OSCE is to assess a nurse practitioner student's competence and safety in the performance of commonly used advanced clinical practice skills. Students often feel nervous when preparing for and participating in an OSCE. Consideration of these identified anxieties led to the development of an alternative method of meeting students' OSCE learning and preparation needs; namely video-recorded simulated OSCEs. Video-recording was appealing for the following reasons: it provides a flexible usage of staff resources and time; OSCE performance mistakes can be rectified; it is possible to use the same video-recordings with multiple cohorts of students, and the recordings can be made conveniently available for students with video streaming on internet-based video-sharing sites or virtual learning environments. The aim of the study was to explore the value of using such recordings amongst nurse practitioner students, via online and face-to-face focus groups, to see if they are a suitable OSCE educational preparation technique. The study findings indicate that simulated OSCE video-recordings are an effective method for supporting nurse practitioner educational development. Copyright 2009 Elsevier Ltd. All rights reserved.

Transcoding method from H.264/AVC to high efficiency video coding based on similarity of intraprediction, interprediction, and motion vector

NASA Astrophysics Data System (ADS)

Liu, Mei-Feng; Zhong, Guo-Yun; He, Xiao-Hai; Qing, Lin-Bo

2016-09-01

Currently, most video resources on line are encoded in the H.264/AVC format. More fluent video transmission can be obtained if these resources are encoded in the newest international video coding standard: high efficiency video coding (HEVC). In order to improve the video transmission and storage on line, a transcoding method from H.264/AVC to HEVC is proposed. In this transcoding algorithm, the coding information of intraprediction, interprediction, and motion vector (MV) in H.264/AVC video stream are used to accelerate the coding in HEVC. It is found through experiments that the region of interprediction in HEVC overlaps that in H.264/AVC. Therefore, the intraprediction for the region in HEVC, which is interpredicted in H.264/AVC, can be skipped to reduce coding complexity. Several macroblocks in H.264/AVC are combined into one PU in HEVC when the MV difference between two of the macroblocks in H.264/AVC is lower than a threshold. This method selects only one coding unit depth and one prediction unit (PU) mode to reduce the coding complexity. An MV interpolation method of combined PU in HEVC is proposed according to the areas and distances between the center of one macroblock in H.264/AVC and that of the PU in HEVC. The predicted MV accelerates the motion estimation for HEVC coding. The simulation results show that our proposed algorithm achieves significant coding time reduction with a little loss in bitrates distortion rate, compared to the existing transcoding algorithms and normal HEVC coding.

Winter bird population studies and project prairie birds for surveying grassland birds

Treesearch

Daniel J. Twedt; Paul B. Hamel; Mark S. Woodrey

2008-01-01

We compared 2 survey methods for assessing winter bird communities in temperate grasslands: Winter Bird Population Study surveys are area-searches that have long been used in a variety of habitats whereas Project Prairie Bird surveys employ active-flushing techniques on strip-transects and are intended for use in grasslands.

Methods for measuring populations of small, diurnal forest birds.

Treesearch

D.A. Manuwal; A.B. Carey

1991-01-01

Before a bird population is measured, the objectives of the study should be clearly defined. Important factors to be considered in designing a study are study site selection, plot size or transect length, distance between sampling points, duration of counts, and frequency and timing of sampling. Qualified field personnel are especially important. Assumptions applying...

The transect of happiness and community’s capability in urbanizing Yogyakarta

NASA Astrophysics Data System (ADS)

Pramono, RWD

2018-03-01

The idea of this paper is that happy-friendly city is it that able to support capability. In addition to factors affixed to an individual, an important element determining someone’s happiness is the quality of a place. This research tries to explain the role of quality of place formed by urbanization process by taking Yogyakarta case as the sample. The importance of variation of particular area caused by urbanization is revealed using transect method. This method showed the shifting gradation from the very center of the city that first experienced urbanization up to the peripheral that experienced it last. The initial result of this clustered-multistage random sampling shows a gradation in capability. It also describes the similar tendency regarding self-evaluation against happiness although not very clear. Further analysis is conducted to define influencing factors. They consist of 40 capability assets that belong to Individual Tangible Asset, Public Tangible Asset, Individual Intangible Asset, Social Institutional Asset, and Economic Institutional Asset. However, the focus of analysis will be on variables included in Public Tangible Asset, Social Institutional Asset, and Economic Institutional Asset called as place-attached assets.

A Rapid Auto-Indexing Technology for Designing Readable E-Learning Content

ERIC Educational Resources Information Center

Yu, Pao-Ta; Liao, Yuan-Hsun; Su, Ming-Hsiang; Cheng, Po-Jen; Pai, Chun-Hsuan

2012-01-01

A rapid scene indexing method is proposed to improve retrieval performance for students accessing instructional videos. This indexing method is applied to anchor suitable indices to the instructional video so that students can obtain several small lesson units to gain learning mastery. The method also regulates online course progress. These…

Dynamic Power-Saving Method for Wi-Fi Direct Based IoT Networks Considering Variable-Bit-Rate Video Traffic.

PubMed

Jin, Meihua; Jung, Ji-Young; Lee, Jung-Ryun

2016-10-12

With the arrival of the era of Internet of Things (IoT), Wi-Fi Direct is becoming an emerging wireless technology that allows one to communicate through a direct connection between the mobile devices anytime, anywhere. In Wi-Fi Direct-based IoT networks, all devices are categorized by group of owner (GO) and client. Since portability is emphasized in Wi-Fi Direct devices, it is essential to control the energy consumption of a device very efficiently. In order to avoid unnecessary power consumed by GO, Wi-Fi Direct standard defines two power-saving methods: Opportunistic and Notice of Absence (NoA) power-saving methods. In this paper, we suggest an algorithm to enhance the energy efficiency of Wi-Fi Direct power-saving, considering the characteristics of multimedia video traffic. Proposed algorithm utilizes the statistical distribution for the size of video frames and adjusts the lengths of awake intervals in a beacon interval dynamically. In addition, considering the inter-dependency among video frames, the proposed algorithm ensures that a video frame having high priority is transmitted with higher probability than other frames having low priority. Simulation results show that the proposed method outperforms the traditional NoA method in terms of average delay and energy efficiency.

Dynamic Power-Saving Method for Wi-Fi Direct Based IoT Networks Considering Variable-Bit-Rate Video Traffic

PubMed Central

Jin, Meihua; Jung, Ji-Young; Lee, Jung-Ryun

2016-01-01

With the arrival of the era of Internet of Things (IoT), Wi-Fi Direct is becoming an emerging wireless technology that allows one to communicate through a direct connection between the mobile devices anytime, anywhere. In Wi-Fi Direct-based IoT networks, all devices are categorized by group of owner (GO) and client. Since portability is emphasized in Wi-Fi Direct devices, it is essential to control the energy consumption of a device very efficiently. In order to avoid unnecessary power consumed by GO, Wi-Fi Direct standard defines two power-saving methods: Opportunistic and Notice of Absence (NoA) power-saving methods. In this paper, we suggest an algorithm to enhance the energy efficiency of Wi-Fi Direct power-saving, considering the characteristics of multimedia video traffic. Proposed algorithm utilizes the statistical distribution for the size of video frames and adjusts the lengths of awake intervals in a beacon interval dynamically. In addition, considering the inter-dependency among video frames, the proposed algorithm ensures that a video frame having high priority is transmitted with higher probability than other frames having low priority. Simulation results show that the proposed method outperforms the traditional NoA method in terms of average delay and energy efficiency. PMID:27754315

Blind identification of full-field vibration modes from video measurements with phase-based video motion magnification

NASA Astrophysics Data System (ADS)

Yang, Yongchao; Dorn, Charles; Mancini, Tyler; Talken, Zachary; Kenyon, Garrett; Farrar, Charles; Mascareñas, David

2017-02-01

Experimental or operational modal analysis traditionally requires physically-attached wired or wireless sensors for vibration measurement of structures. This instrumentation can result in mass-loading on lightweight structures, and is costly and time-consuming to install and maintain on large civil structures, especially for long-term applications (e.g., structural health monitoring) that require significant maintenance for cabling (wired sensors) or periodic replacement of the energy supply (wireless sensors). Moreover, these sensors are typically placed at a limited number of discrete locations, providing low spatial sensing resolution that is hardly sufficient for modal-based damage localization, or model correlation and updating for larger-scale structures. Non-contact measurement methods such as scanning laser vibrometers provide high-resolution sensing capacity without the mass-loading effect; however, they make sequential measurements that require considerable acquisition time. As an alternative non-contact method, digital video cameras are relatively low-cost, agile, and provide high spatial resolution, simultaneous, measurements. Combined with vision based algorithms (e.g., image correlation, optical flow), video camera based measurements have been successfully used for vibration measurements and subsequent modal analysis, based on techniques such as the digital image correlation (DIC) and the point-tracking. However, they typically require speckle pattern or high-contrast markers to be placed on the surface of structures, which poses challenges when the measurement area is large or inaccessible. This work explores advanced computer vision and video processing algorithms to develop a novel video measurement and vision-based operational (output-only) modal analysis method that alleviate the need of structural surface preparation associated with existing vision-based methods and can be implemented in a relatively efficient and autonomous manner with little user supervision and calibration. First a multi-scale image processing method is applied on the frames of the video of a vibrating structure to extract the local pixel phases that encode local structural vibration, establishing a full-field spatiotemporal motion matrix. Then a high-spatial dimensional, yet low-modal-dimensional, over-complete model is used to represent the extracted full-field motion matrix using modal superposition, which is physically connected and manipulated by a family of unsupervised learning models and techniques, respectively. Thus, the proposed method is able to blindly extract modal frequencies, damping ratios, and full-field (as many points as the pixel number of the video frame) mode shapes from line of sight video measurements of the structure. The method is validated by laboratory experiments on a bench-scale building structure and a cantilever beam. Its ability for output (video measurements)-only identification and visualization of the weakly-excited mode is demonstrated and several issues with its implementation are discussed.

Surgical gesture segmentation and recognition.

PubMed

Tao, Lingling; Zappella, Luca; Hager, Gregory D; Vidal, René

2013-01-01

Automatic surgical gesture segmentation and recognition can provide useful feedback for surgical training in robotic surgery. Most prior work in this field relies on the robot's kinematic data. Although recent work [1,2] shows that the robot's video data can be equally effective for surgical gesture recognition, the segmentation of the video into gestures is assumed to be known. In this paper, we propose a framework for joint segmentation and recognition of surgical gestures from kinematic and video data. Unlike prior work that relies on either frame-level kinematic cues, or segment-level kinematic or video cues, our approach exploits both cues by using a combined Markov/semi-Markov conditional random field (MsM-CRF) model. Our experiments show that the proposed model improves over a Markov or semi-Markov CRF when using video data alone, gives results that are comparable to state-of-the-art methods on kinematic data alone, and improves over state-of-the-art methods when combining kinematic and video data.

Concurrent Validity Between Live and Home Video Observations Using the Alberta Infant Motor Scale

PubMed Central

van Dam, Ellen; van Haastert, Ingrid C.; Nuysink, Jacqueline

2017-01-01

Purpose: Serial assessment of gross motor development of infants at risk is an established procedure in neonatal follow-up clinics. Assessments based on home video recordings could be a relevant addition. Methods: In 48 infants (1.5-19 months), the concurrent validity of 2 applications was examined using the Alberta Infant Motor Scale: (1) a home video made by parents and (2) simultaneous observation on-site by a pediatric physical therapist. Parents' experiences were explored using a questionnaire. Results: The intraclass correlation coefficient agreement between live and home video assessment was 0.99, with a standard error of measurement of 1.41 items. Intra- and interrater reliability: intraclass correlation coefficients were more than 0.99. According to 94% of the parents, recording their infant's movement repertoire was easy to perform. Conclusion: Assessing the Alberta Infant Motor Scale based on home video recordings is comparable to assessment by live observation. The video method is a promising application that can be used with low burden for parents and infants. PMID:28350771

A Video Ethnography Approach for Linking Naturalistic Behaviors to Research Constructs of Neurocognition in Schizophrenia

PubMed Central

Bromley, Elizabeth; Adams, Gail Fox; Brekke, John S.

2015-01-01

Few methods are available to explore the impact of neurocognition in schizophrenia on behaviors performed in usual contexts. The authors developed a video ethnography approach to examine the relationship between naturalistic behaviors and research constructs of neurocognition. Video ethnographers accompanied subjects through usual routines gathering continuous video data. Researchers developed codes to measure four behavioral domains observed on video. This paper describes the psychometric characteristics to be considered in the development of observational approaches. It also highlights differences between behaviors performed in usual environments and neuropsychological constructs. The authors demonstrate that everyday behaviors that have been shown to correspond to neurocognitive skills in a pilot feasibility study1 can be identified and rated. They further suggest that observational methods could provide novel strategies for linking research findings and clinical concerns. PMID:22772661

Registration of multiple video images to preoperative CT for image-guided surgery

NASA Astrophysics Data System (ADS)

Clarkson, Matthew J.; Rueckert, Daniel; Hill, Derek L.; Hawkes, David J.

1999-05-01

In this paper we propose a method which uses multiple video images to establish the pose of a CT volume with respect to video camera coordinates for use in image guided surgery. The majority of neurosurgical procedures require the neurosurgeon to relate the pre-operative MR/CT data to the intra-operative scene. Registration of 2D video images to the pre-operative 3D image enables a perspective projection of the pre-operative data to be overlaid onto the video image. Our registration method is based on image intensity and uses a simple iterative optimization scheme to maximize the mutual information between a video image and a rendering from the pre-operative data. Video images are obtained from a stereo operating microscope, with a field of view of approximately 110 X 80 mm. We have extended an existing information theoretical framework for 2D-3D registration, so that multiple video images can be registered simultaneously to the pre-operative data. Experiments were performed on video and CT images of a skull phantom. We took three video images, and our algorithm registered these individually to the 3D image. The mean projection error varied between 4.33 and 9.81 millimeters (mm), and the mean 3D error varied between 4.47 and 11.92 mm. Using our novel techniques we then registered five video views simultaneously to the 3D model. This produced an accurate and robust registration with a mean projection error of 0.68 mm and a mean 3D error of 1.05 mm.

Service provider perceptions of transitioning from audio to video capability in a telehealth system: a qualitative evaluation.

PubMed

Clay-Williams, Robyn; Baysari, Melissa; Taylor, Natalie; Zalitis, Dianne; Georgiou, Andrew; Robinson, Maureen; Braithwaite, Jeffrey; Westbrook, Johanna

2017-08-14

Telephone consultation and triage services are increasingly being used to deliver health advice. Availability of high speed internet services in remote areas allows healthcare providers to move from telephone to video telehealth services. Current approaches for assessing video services have limitations. This study aimed to identify the challenges for service providers associated with transitioning from audio to video technology. Using a mixed-method, qualitative approach, we observed training of service providers who were required to switch from telephone to video, and conducted pre- and post-training interviews with 15 service providers and their trainers on the challenges associated with transitioning to video. Two full days of simulation training were observed. Data were transcribed and analysed using an inductive approach; a modified constant comparative method was employed to identify common themes. We found three broad categories of issues likely to affect implementation of the video service: social, professional, and technical. Within these categories, eight sub-themes were identified; they were: enhanced delivery of the health service, improved health advice for people living in remote areas, safety concerns, professional risks, poor uptake of video service, system design issues, use of simulation for system testing, and use of simulation for system training. This study identified a number of unexpected potential barriers to successful transition from telephone to the video system. Most prominent were technical and training issues, and personal safety concerns about transitioning from telephone to video media. Addressing identified issues prior to implementation of a new video telehealth system is likely to improve effectiveness and uptake.

Deep RNNs for video denoising

NASA Astrophysics Data System (ADS)

Chen, Xinyuan; Song, Li; Yang, Xiaokang

2016-09-01

Video denoising can be described as the problem of mapping from a specific length of noisy frames to clean one. We propose a deep architecture based on Recurrent Neural Network (RNN) for video denoising. The model learns a patch-based end-to-end mapping between the clean and noisy video sequences. It takes the corrupted video sequences as the input and outputs the clean one. Our deep network, which we refer to as deep Recurrent Neural Networks (deep RNNs or DRNNs), stacks RNN layers where each layer receives the hidden state of the previous layer as input. Experiment shows (i) the recurrent architecture through temporal domain extracts motion information and does favor to video denoising, and (ii) deep architecture have large enough capacity for expressing mapping relation between corrupted videos as input and clean videos as output, furthermore, (iii) the model has generality to learned different mappings from videos corrupted by different types of noise (e.g., Poisson-Gaussian noise). By training on large video databases, we are able to compete with some existing video denoising methods.

Efficient Use of Video for 3d Modelling of Cultural Heritage Objects

NASA Astrophysics Data System (ADS)

Alsadik, B.; Gerke, M.; Vosselman, G.

2015-03-01

Currently, there is a rapid development in the techniques of the automated image based modelling (IBM), especially in advanced structure-from-motion (SFM) and dense image matching methods, and camera technology. One possibility is to use video imaging to create 3D reality based models of cultural heritage architectures and monuments. Practically, video imaging is much easier to apply when compared to still image shooting in IBM techniques because the latter needs a thorough planning and proficiency. However, one is faced with mainly three problems when video image sequences are used for highly detailed modelling and dimensional survey of cultural heritage objects. These problems are: the low resolution of video images, the need to process a large number of short baseline video images and blur effects due to camera shake on a significant number of images. In this research, the feasibility of using video images for efficient 3D modelling is investigated. A method is developed to find the minimal significant number of video images in terms of object coverage and blur effect. This reduction in video images is convenient to decrease the processing time and to create a reliable textured 3D model compared with models produced by still imaging. Two experiments for modelling a building and a monument are tested using a video image resolution of 1920×1080 pixels. Internal and external validations of the produced models are applied to find out the final predicted accuracy and the model level of details. Related to the object complexity and video imaging resolution, the tests show an achievable average accuracy between 1 - 5 cm when using video imaging, which is suitable for visualization, virtual museums and low detailed documentation.

Problem-based learning using patient-simulated videos showing daily life for a comprehensive clinical approach

PubMed Central

Ohira, Yoshiyuki; Uehara, Takanori; Noda, Kazutaka; Suzuki, Shingo; Shikino, Kiyoshi; Kajiwara, Hideki; Kondo, Takeshi; Hirota, Yusuke; Ikusaka, Masatomi

2017-01-01

Objectives We examined whether problem-based learning tutorials using patient-simulated videos showing daily life are more practical for clinical learning, compared with traditional paper-based problem-based learning, for the consideration rate of psychosocial issues and the recall rate for experienced learning. Methods Twenty-two groups with 120 fifth-year students were each assigned paper-based problem-based learning and video-based problem-based learning using patient-simulated videos. We compared target achievement rates in questionnaires using the Wilcoxon signed-rank test and discussion contents diversity using the Mann-Whitney U test. A follow-up survey used a chi-square test to measure students’ recall of cases in three categories: video, paper, and non-experienced. Results Video-based problem-based learning displayed significantly higher achievement rates for imagining authentic patients (p=0.001), incorporating a comprehensive approach including psychosocial aspects (p<0.001), and satisfaction with sessions (p=0.001). No significant differences existed in the discussion contents diversity regarding the International Classification of Primary Care Second Edition codes and chapter types or in the rate of psychological codes. In a follow-up survey comparing video and paper groups to non-experienced groups, the rates were higher for video (χ2=24.319, p<0.001) and paper (χ2=11.134, p=0.001). Although the video rate tended to be higher than the paper rate, no significant difference was found between the two. Conclusions Patient-simulated videos showing daily life facilitate imagining true patients and support a comprehensive approach that fosters better memory. The clinical patient-simulated video method is more practical and clinical problem-based tutorials can be implemented if we create patient-simulated videos for each symptom as teaching materials.  PMID:28245193

Improving Video Based Heart Rate Monitoring.

PubMed

Lin, Jian; Rozado, David; Duenser, Andreas

2015-01-01

Non-contact measurements of cardiac pulse can provide robust measurement of heart rate (HR) without the annoyance of attaching electrodes to the body. In this paper we explore a novel and reliable method to carry out video-based HR estimation and propose various performance improvement over existing approaches. The investigated method uses Independent Component Analysis (ICA) to detect the underlying HR signal from a mixed source signal present in the RGB channels of the image. The original ICA algorithm was implemented and several modifications were explored in order to determine which one could be optimal for accurate HR estimation. Using statistical analysis, we compared the cardiac pulse rate estimation from the different methods under comparison on the extracted videos to a commercially available oximeter. We found that some of these methods are quite effective and efficient in terms of improving accuracy and latency of the system. We have made the code of our algorithms openly available to the scientific community so that other researchers can explore how to integrate video-based HR monitoring in novel health technology applications. We conclude by noting that recent advances in video-based HR monitoring permit computers to be aware of a user's psychophysiological status in real time.

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.

Super-Resolution for "Jilin-1" Satellite Video Imagery via a Convolutional Network.

PubMed

Xiao, Aoran; Wang, Zhongyuan; Wang, Lei; Ren, Yexian

2018-04-13

Super-resolution for satellite video attaches much significance to earth observation accuracy, and the special imaging and transmission conditions on the video satellite pose great challenges to this task. The existing deep convolutional neural-network-based methods require pre-processing or post-processing to be adapted to a high-resolution size or pixel format, leading to reduced performance and extra complexity. To this end, this paper proposes a five-layer end-to-end network structure without any pre-processing and post-processing, but imposes a reshape or deconvolution layer at the end of the network to retain the distribution of ground objects within the image. Meanwhile, we formulate a joint loss function by combining the output and high-dimensional features of a non-linear mapping network to precisely learn the desirable mapping relationship between low-resolution images and their high-resolution counterparts. Also, we use satellite video data itself as a training set, which favors consistency between training and testing images and promotes the method's practicality. Experimental results on "Jilin-1" satellite video imagery show that this method demonstrates a superior performance in terms of both visual effects and measure metrics over competing methods.

NGEE Arctic Plant Traits: Shrub Transects, Kougarok Road Mile Marker 64, Seward Peninsula, Alaska, 2016

DOE Data Explorer

Verity Salmon; Colleen Iversen; Peter Thornton; Ma

2017-03-01

Transect data is from point center quarter surveys for shrub density performed in July 2016 at the Kougarok hill slope located at Kougarok Road, Mile Marker 64. For each sample point along the transects, moving averages for shrub density and shrub basal area are provided along with GPS coordinates, average shrub height and active layer depth. The individual height, basal area, and species of surveyed shrubs are also included. Data upload will be completed January 2017.

High efficiency video coding for ultrasound video communication in m-health systems.

PubMed

Panayides, A; Antoniou, Z; Pattichis, M S; Pattichis, C S; Constantinides, A G

2012-01-01

Emerging high efficiency video compression methods and wider availability of wireless network infrastructure will significantly advance existing m-health applications. For medical video communications, the emerging video compression and network standards support low-delay and high-resolution video transmission, at the clinically acquired resolution and frame rates. Such advances are expected to further promote the adoption of m-health systems for remote diagnosis and emergency incidents in daily clinical practice. This paper compares the performance of the emerging high efficiency video coding (HEVC) standard to the current state-of-the-art H.264/AVC standard. The experimental evaluation, based on five atherosclerotic plaque ultrasound videos encoded at QCIF, CIF, and 4CIF resolutions demonstrates that 50% reductions in bitrate requirements is possible for equivalent clinical quality.

Automatic Mrf-Based Registration of High Resolution Satellite Video Data

NASA Astrophysics Data System (ADS)

Platias, C.; Vakalopoulou, M.; Karantzalos, K.

2016-06-01

In this paper we propose a deformable registration framework for high resolution satellite video data able to automatically and accurately co-register satellite video frames and/or register them to a reference map/image. The proposed approach performs non-rigid registration, formulates a Markov Random Fields (MRF) model, while efficient linear programming is employed for reaching the lowest potential of the cost function. The developed approach has been applied and validated on satellite video sequences from Skybox Imaging and compared with a rigid, descriptor-based registration method. Regarding the computational performance, both the MRF-based and the descriptor-based methods were quite efficient, with the first one converging in some minutes and the second in some seconds. Regarding the registration accuracy the proposed MRF-based method significantly outperformed the descriptor-based one in all the performing experiments.

VQone MATLAB toolbox: A graphical experiment builder for image and video quality evaluations: VQone MATLAB toolbox.

PubMed

Nuutinen, Mikko; Virtanen, Toni; Rummukainen, Olli; Häkkinen, Jukka

2016-03-01

This article presents VQone, a graphical experiment builder, written as a MATLAB toolbox, developed for image and video quality ratings. VQone contains the main elements needed for the subjective image and video quality rating process. This includes building and conducting experiments and data analysis. All functions can be controlled through graphical user interfaces. The experiment builder includes many standardized image and video quality rating methods. Moreover, it enables the creation of new methods or modified versions from standard methods. VQone is distributed free of charge under the terms of the GNU general public license and allows code modifications to be made so that the program's functions can be adjusted according to a user's requirements. VQone is available for download from the project page (http://www.helsinki.fi/psychology/groups/visualcognition/).

On the Design of the Peer-Assisted UGC VoD System

NASA Astrophysics Data System (ADS)

Wan, Yi; Asaka, Takuya; Takahashi, Tatsuro

User Generated Content (UGC) VoD services such as YouTube are becoming more and more popular, and their maintenance costs are growing as well. Many P2P solutions have been proposed to reduce server load in such systems, but almost all of them focus on the single-video approach, which only has limited effect on the systems serving short videos such as UGC. The purpose of this paper is to investigate the potential of an alternative approach, the multi-video approach, and we use a very simple method called collaborative caching to show that methods using the multi-video approach are generally more suitable for current UGC VoD systems. We also study the influence of the major design factors through simulations and provide guidelines for efficiently building systems with this method.

Reconstructing Interlaced High-Dynamic-Range Video Using Joint Learning.

PubMed

Inchang Choi; Seung-Hwan Baek; Kim, Min H

2017-11-01

For extending the dynamic range of video, it is a common practice to capture multiple frames sequentially with different exposures and combine them to extend the dynamic range of each video frame. However, this approach results in typical ghosting artifacts due to fast and complex motion in nature. As an alternative, video imaging with interlaced exposures has been introduced to extend the dynamic range. However, the interlaced approach has been hindered by jaggy artifacts and sensor noise, leading to concerns over image quality. In this paper, we propose a data-driven approach for jointly solving two specific problems of deinterlacing and denoising that arise in interlaced video imaging with different exposures. First, we solve the deinterlacing problem using joint dictionary learning via sparse coding. Since partial information of detail in differently exposed rows is often available via interlacing, we make use of the information to reconstruct details of the extended dynamic range from the interlaced video input. Second, we jointly solve the denoising problem by tailoring sparse coding to better handle additive noise in low-/high-exposure rows, and also adopt multiscale homography flow to temporal sequences for denoising. We anticipate that the proposed method will allow for concurrent capture of higher dynamic range video frames without suffering from ghosting artifacts. We demonstrate the advantages of our interlaced video imaging compared with the state-of-the-art high-dynamic-range video methods.

Using multimedia tools and high-fidelity simulations to improve medical students' resuscitation performance: an observational study

PubMed Central

Wang, Candice; Huang, Chin-Chou; Lin, Shing-Jong; Chen, Jaw-Wen

2016-01-01

Objectives The goal of our study was to shed light on educational methods to strengthen medical students' cardiopulmonary resuscitation (CPR) leadership and team skills in order to optimise CPR understanding and success using didactic videos and high-fidelity simulations. Design An observational study. Setting A tertiary medical centre in Northern Taiwan. Participants A total of 104 5–7th year medical students, including 72 men and 32 women. Interventions We provided the medical students with a 2-hour training session on advanced CPR. During each class, we divided the students into 1–2 groups; each group consisted of 4–6 team members. Medical student teams were trained by using either method A or B. Method A started with an instructional CPR video followed by a first CPR simulation. Method B started with a first CPR simulation followed by an instructional CPR video. All students then participated in a second CPR simulation. Outcome measures Student teams were assessed with checklist rating scores in leadership, teamwork and team member skills, global rating scores by an attending physician and video-recording evaluation by 2 independent individuals. Results The 104 medical students were divided into 22 teams. We trained 11 teams using method A and 11 using method B. Total second CPR simulation scores were significantly higher than first CPR simulation scores in leadership (p<0.001), teamwork (p<0.001) and team member skills (p<0.001). For methods A and B students' first CPR simulation scores were similar, but method A students' second CPR simulation scores were significantly higher than those of method B in leadership skills (p=0.034), specifically in the support subcategory (p=0.049). Conclusions Although both teaching strategies improved leadership, teamwork and team member performance, video exposure followed by CPR simulation further increased students' leadership skills compared with CPR simulation followed by video exposure. PMID:27678539

Acceptability of instructional videos.

PubMed

Rayyan, Mohammad; Elagra, Marwa; Alfataftah, Nida; Alammar, Amirah

2017-08-01

Over the past few decades, instructional videos have been incorporated as important tools in the dental classroom setting. This study aimed to investigate the acceptability of video demonstrations in comparison with live broadcasting and with the traditional face-to-face demonstrations in preclinical fixed prosthodontic classes. A group of dental students who have been exposed to three different methods of delivering practical demonstrations - face-to-face demonstrations, live broadcasting and recorded instructional videos - were included in the study. Preferences regarding these three methods were investigated using a questionnaire comprising a number of closed- and open-ended questions. Descriptive statistics were used to analyse the survey data using spss software. Survey comments were summarised and coded into categories. A total of 163 questionnaires were distributed, and 145 responses were returned (a response rate of 89%). Ninety-two students (63%) considered the recorded video demonstrations to be the most convenient. Moreover, ninety-seven students (67%) found live demonstrations to be the least convenient. The majority of students either agreed (67 students) or strongly agreed (60 students) that watching the video before the session made it easier for them to perform the procedure in the lab. Recorded instructional videos were the preferred method of delivering practical demonstrations for students in the preclinical courses of fixed prosthodontics. Instructors must focus on using the technological aids to increase their positive interaction with students. Instructional videos have been incorporated as important tools in the dental classroom setting. © 2016 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Using video recording to identify management errors in pediatric trauma resuscitation.

PubMed

Oakley, Ed; Stocker, Sergio; Staubli, Georg; Young, Simon

2006-03-01

To determine the ability of video recording to identify management errors in trauma resuscitation and to compare this method with medical record review. The resuscitation of children who presented to the emergency department of the Royal Children's Hospital between February 19, 2001, and August 18, 2002, for whom the trauma team was activated was video recorded. The tapes were analyzed, and management was compared with Advanced Trauma Life Support guidelines. Deviations from these guidelines were recorded as errors. Fifty video recordings were analyzed independently by 2 reviewers. Medical record review was undertaken for a cohort of the most seriously injured patients, and errors were identified. The errors detected with the 2 methods were compared. Ninety resuscitations were video recorded and analyzed. An average of 5.9 errors per resuscitation was identified with this method (range: 1-12 errors). Twenty-five children (28%) had an injury severity score of >11; there was an average of 2.16 errors per patient in this group. Only 10 (20%) of these errors were detected in the medical record review. Medical record review detected an additional 8 errors that were not evident on the video recordings. Concordance between independent reviewers was high, with 93% agreement. Video recording is more effective than medical record review in detecting management errors in pediatric trauma resuscitation. Management errors in pediatric trauma resuscitation are common and often involve basic resuscitation principles. Resuscitation of the most seriously injured children was associated with fewer errors. Video recording is a useful adjunct to trauma resuscitation auditing.

Effects of excluding goat herbivory on Acacia tortilis woodland around pastoralist settlements in northwest Kenya

NASA Astrophysics Data System (ADS)

Oba, Gufu

1998-08-01

Browsing by goats is considered to cause poor tree regeneration and reduced tree growth around settlements throughout the arid zones of sub-Saharan Africa. This study investigated whether excluding goats from Acacia tortilis woodlands increased tree regeneration, current season's shoot growth rates and browse production over a period of 52 months between 1986 and 1990. The study also investigated the effects of climatic variability on tree growth and browse production. Excluding goat herbivory provided no advantage over continuous browsing for juvenile A. tortilis. Trees on the unbrowsed and on browsed transects increased by 22.2 (standard error [SE] ± 0.53) cm·yr -1 and 25.0 (SE ± 0.58) cm·yr -1, respectively. Fewer but longer shoots were produced by trees on the unbrowsed transects, while trees on the browsed transects invested more in shorter shoots. Net total browse production was lower on unbrowsed (1.73 [standard deviation (SD) ± 4.3] t·ha -1·yr -1) than on the browsed (3.03 [SD ± 3.6] t·ha -1 ·yr -1) transects. Biomass production on unbrowsed and browsed transects was closely correlated with rainfall and presumably soil moisture during wet seasons. Relative growth rates (RGR) of current season's shoots in the two treatments did not differ, implying goat herbivory at moderate stocking density (i.e. 13.0 tropical livestock units [TLU]·km -2) stimulated shoot growth. RGR remained positive except on the browsed transects during 1990, a dry year. Goat browsing pressure was moderate. Total biomass loss on unbrowsed transects was 15.5 %·yr -1 compared with 27.7 %·yr -1 on the browsed transects. These findings do not support the notion that goats always destroy young trees around settlements. Goat herbivory at moderate intensity stimulated shoot productivity. However, the results should not be used to generalize all conditions throughout sub-Saharan Africa, let alone the arid zones of northern Kenya. Rather, there is a need to emphasize individual case studies that ultimately can be used for managing degraded woodlands near pastoralist settlements.

Nerve transection repair using laser-activated chitosan in a rat model.

PubMed

Bhatt, Neel K; Khan, Taleef R; Mejias, Christopher; Paniello, Randal C

2017-08-01

Cranial nerve transection during head and neck surgery is conventionally repaired with microsuture. Previous studies have demonstrated recovery with laser nerve welding (LNW), a novel alternative to microsuture. LNW has been reported to have poorer tensile strength, however. Laser-activated chitosan, an adhesive biopolymer, may promote nerve recovery while enhancing the tensile strength of the repair. Using a rat posterior tibial nerve injury model, we compared four different methods of nerve repair in this pilot study. Animal study. Animals underwent unilateral posterior tibial nerve transection. The injury was repaired by potassium titanyl phosphate (KTP) laser alone (n = 20), KTP + chitosan (n = 12), microsuture + chitosan (n = 12), and chitosan alone (n = 14). Weekly walking tracks were conducted to measure functional recovery (FR). Tensile strength (TS) was measured at 6 weeks. At 6 weeks, KTP laser alone had the best recovery (FR = 93.4% ± 8.3%). Microsuture + chitosan, KTP + chitosan, and chitosan alone all showed good FR (87.4% ± 13.5%, 84.6% ± 13.0%, and 84.1% ± 10.0%, respectively). One-way analysis of variance was performed (F(3,56) = 2.6, P = .061). A TS threshold of 3.8 N was selected as a control mean recovery. Three groups-KTP alone, KTP + chitosan, and microsuture + chitosan-were found to meet threshold 60% (95% confidence interval [CI]: 23.1%-88.3%), 75% (95% CI: 46.8%-91.1%), and 100% (95% CI: 75.8%-100.0%), respectively. In the posterior tibial nerve model, all repair methods promoted nerve recovery. Laser-activated chitosan as a biopolymer anchor provided good TS and appears to be a novel alternative to microsuture. This repair method may have surgical utility following cranial nerve injury during head and neck surgery. NA Laryngoscope, 127:E253-E257, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Linking landscapes and habitat suitability scores for diadromous fish restoration in the susquehanna river basin

USGS Publications Warehouse

Kocovsky, P.M.; Ross, R.M.; Dropkin, D.S.; Campbell, J.M.

2008-01-01

Dams within the Susquehanna River drainage, Pennsylvania, are potential barriers to migration of diadromous fishes, and many are under consideration for removal to facilitate fish passage. To provide useful input for prioritizing dam removal, we examined relations between landscape-scale factors and habitat suitability indices (HSIs) for native diadromous species of the Susquehanna River. We used two different methods (U.S. Fish and Wildlife Service method: Stier and Crance [1985], Ross et al. [1993a, 1993b, 1997], and Pardue [1983]; Pennsylvania State University method: Carline et al. [1994]) to calculate HSIs for several life stages of American shad Alosa sapidissima, alewives Alosa pseudoharengus, and blueback herring Alosa aestivalis and a single HSI for American eels Anguilla rostrata based on habitat variables measured at transects spaced every 5 km on six major Susquehanna River tributaries. Using geographical information systems, we calculated land use and geologic variables upstream from each transect and associated those data with HSIs calculated at each transect. We then performed canonical correlation analysis to determine how HSIs were linked to geologic and land use factors. Canonical correlation analysis identified the proportion of watershed underlain by carbonate rock as a positive correlate of HSIs for all species and life stages except American eels and juvenile blueback herring. We hypothesize that potential mechanisms linking carbonate rock to habitat suitability include increased productivity and buffering capacity. No other consistent patterns of positive or negative correlation between landscape-scale factors and HSIs were evident. This analysis will be useful for prioritizing removal of dams in the Susquehanna River drainage, because it provides a broad perspective on relationships between habitat suitability for diadromous fishes and easily measured landscape factors. This approach can be applied elsewhere to elucidate relationships between fine- and coarse-scale variables and suitability of habitat for fishes. ?? Copyright by the American Fisheries Society 2008.

Advantages of Live Microscope Video for Laboratory and Teaching Applications

ERIC Educational Resources Information Center

Michels, Kristin K.; Michels, Zachary D.; Hotchkiss, Sara C.

2016-01-01

Although spatial reasoning and penetrative thinking skills are essential for many disciplines, these concepts are difficult for students to comprehend. In microscopy, traditional educational materials (i.e., photographs) are static. Conversely, video-based training methods convey dimensionality. We implemented a real-time digital video imaging…

The Effect of Teachers' Professional Development in Video Technology on Mathematics and the English Language Learning of Preschoolers in a Rural Primary School in Pakistan

ERIC Educational Resources Information Center

Ikram, Hamid

2016-01-01

The purpose of this mixed methods study was to examine the effect of teachers' professional development in video technology (PBS & Sesame Street videos) on mathematics and the English language learning among nursery students in the rural area of Pakistan where it was impossible for students to experience watching videos for learning purposes.…

A Novel Approach to High Definition, High-Contrast Video Capture in Abdominal Surgery

PubMed Central

Cosman, Peter H.; Shearer, Christopher J.; Hugh, Thomas J.; Biankin, Andrew V.; Merrett, Neil D.

2007-01-01

Objective: The aim of this study was to define the best available option for video capture of surgical procedures for educational and archival purposes, with a view to identifying methods of capturing high-quality footage and identifying common pitfalls. Summary Background Data: Several options exist for those who wish to record operative surgical techniques on video. While high-end equipment is an unnecessary expense for most surgical units, several techniques are readily available that do not require industrial-grade audiovisual recording facilities, but not all are suited to every surgical application. Methods: We surveyed and evaluated the available technology for video capture in surgery. Our evaluation included analyses of video resolution, depth of field, contrast, exposure, image stability, and frame composition, as well as considerations of cost, accessibility, utility, feasibility, and economies of scale. Results: Several video capture options were identified, and the strengths and shortcomings of each were catalogued. None of the commercially available options was deemed suitable for high-quality video capture of abdominal surgical procedures. A novel application of off-the-shelf technology was devised to address these issues. Conclusions: Excellent quality video capture of surgical procedures within deep body cavities is feasible using commonly available equipment and technology, with minimal technical difficulty. PMID:17414600

Bayesian Modeling of Temporal Coherence in Videos for Entity Discovery and Summarization.

PubMed

Mitra, Adway; Biswas, Soma; Bhattacharyya, Chiranjib

2017-03-01

A video is understood by users in terms of entities present in it. Entity Discovery is the task of building appearance model for each entity (e.g., a person), and finding all its occurrences in the video. We represent a video as a sequence of tracklets, each spanning 10-20 frames, and associated with one entity. We pose Entity Discovery as tracklet clustering, and approach it by leveraging Temporal Coherence (TC): the property that temporally neighboring tracklets are likely to be associated with the same entity. Our major contributions are the first Bayesian nonparametric models for TC at tracklet-level. We extend Chinese Restaurant Process (CRP) to TC-CRP, and further to Temporally Coherent Chinese Restaurant Franchise (TC-CRF) to jointly model entities and temporal segments using mixture components and sparse distributions. For discovering persons in TV serial videos without meta-data like scripts, these methods show considerable improvement over state-of-the-art approaches to tracklet clustering in terms of clustering accuracy, cluster purity and entity coverage. The proposed methods can perform online tracklet clustering on streaming videos unlike existing approaches, and can automatically reject false tracklets. Finally we discuss entity-driven video summarization- where temporal segments of the video are selected based on the discovered entities, to create a semantically meaningful summary.

Speed Biases With Real-Life Video Clips

PubMed Central

Rossi, Federica; Montanaro, Elisa; de’Sperati, Claudio

2018-01-01

We live almost literally immersed in an artificial visual world, especially motion pictures. In this exploratory study, we asked whether the best speed for reproducing a video is its original, shooting speed. By using adjustment and double staircase methods, we examined speed biases in viewing real-life video clips in three experiments, and assessed their robustness by manipulating visual and auditory factors. With the tested stimuli (short clips of human motion, mixed human-physical motion, physical motion and ego-motion), speed underestimation was the rule rather than the exception, although it depended largely on clip content, ranging on average from 2% (ego-motion) to 32% (physical motion). Manipulating display size or adding arbitrary soundtracks did not modify these speed biases. Estimated speed was not correlated with estimated duration of these same video clips. These results indicate that the sense of speed for real-life video clips can be systematically biased, independently of the impression of elapsed time. Measuring subjective visual tempo may integrate traditional methods that assess time perception: speed biases may be exploited to develop a simple, objective test of reality flow, to be used for example in clinical and developmental contexts. From the perspective of video media, measuring speed biases may help to optimize video reproduction speed and validate “natural” video compression techniques based on sub-threshold temporal squeezing. PMID:29615875