Implications to stormwater management as a result of lot scale rainwater tank systems: a case study in Western Sydney, Australia.

PubMed

van der Sterren, M; Rahman, A; Dennis, G R

2012-01-01

Rainwater tanks are increasingly adopted in Australia to reduce potable water demand and are perceived to reduce the volume of stormwater discharge from developments. This paper investigates the water balance of rainwater tanks, in particular the possible impacts these tanks could have in controlling the stormwater discharge volume. The study collected water quantity data from two sites in the Hawkesbury City Council area, New South Wales, Australia and utilised the collected data in a simple water balance model to assess the effectiveness of rainwater tanks in reducing the stormwater discharge volume. The results indicate that a significant reduction in discharge volume from a lot scale development can be achieved if the rainwater tank is connected to multiple end-uses, but is minimal when using irrigation alone. In addition, the commonly used volumetric runoff coefficient of 0.9 was found to over-estimate the runoff from the roof areas and to thereby under-estimate the available volume within the rainwater tanks for retention or detention. Also, sole reliance on the water in the rainwater tanks can make the users aware of their water use pattern and water availability, resulting in significant reductions in water use as the supply dwindles, through self-imposed water restrictions.

Diethylene glycol in health products sold over-the-counter and imported from Asian countries.

PubMed

Schier, Joshua G; Barr, Dana B; Li, Zheng; Wolkin, Amy F; Baker, Samuel E; Lewis, Lauren S; McGeehin, Michael A

2011-03-01

Diethylene glycol (DEG), a chemical that has been implicated in multiple medication-associated mass poisonings, can result in renal and neurological toxicity if ingested. Three previous such mass poisonings implicated Chinese manufacturers as the origin of contaminated ingredients. No literature exists on potential DEG or triethylene glycol (TEG), a related compound, contamination of health products imported from Asian countries to the USA. Our primary objective was to quantitatively assess the amount of DEG present in a convenience sampling of these health products. The study's secondary objectives were to: (1) evaluate for, and quantify TEG levels in these samples; (2) compare DEG and TEG levels in these products directly to levels in medications implicated in previous similar mass poisonings; and (3) to estimate DEG dose (in mg/kg) based on the manufacturer's instructions and compare these values to toxic doses from past mass poisonings and the literature. A quantitative assessment of DEG and TEG was performed in a convenience sampling of over-the-counter health products imported from Asian countries. Results were converted to volume to volume (v/v) % and compared with DEG levels in medications implicated in previous mass poisonings. Estimated doses (based on the manufacturer's instructions) of each product with detectable levels of DEG for a 70 kg adult were compared to toxic doses of DEG reported in the literature. Seventeen of 85 (20%) samples were not able to be analyzed for DEG or TEG due to technical reasons. Fifteen of 68 (22%) samples successfully tested had detectable levels of DEG (mean, 18.8 μg/ml; range, 0.791-110.1 μg/ml; and volume to volume (v/v) range, 0.00007-0.01%). Two of 68 (3%) samples had TEG levels of 12.8 and 20.2 μg/ml or 0.0012% and 0.0018% TEG v/v. The product with the highest DEG% by v/v was 810 times less than the product involved in the Panama DEG mass poisoning (8.1%). The lowest reported toxic dose from a past DEG mass poisoning (14 mg/kg) was more than 150 times higher than the highest daily dose estimated in our study (0.09 mg/kg). Sixty-eight of 85 (80%) samples were able to be successfully analyzed for DEG and TEG. DEG and TEG were detectable in 15/68 (22%) and 2/68 (3%) samples, respectively. Based on current standards, these levels probably do not represent an acute public health threat. Additional research focusing on why DEG is found in these products and on the minimum amount of DEG needed to result in toxicity is needed. © American College of Medical Toxicology 2010

Oral Cooling and Carbonation Increase the Perception of Drinking and Thirst Quenching in Thirsty Adults

PubMed Central

Peyrot des Gachons, Catherine; Avrillier, Julie; Gleason, Michael; Algarra, Laure; Zhang, Siyu; Mura, Emi; Nagai, Hajime

2016-01-01

Fluid ingestion is necessary for life, and thirst sensations are a prime motivator to drink. There is evidence of the influence of oropharyngeal stimulation on thirst and water intake in both animals and humans, but how those oral sensory cues impact thirst and ultimately the amount of liquid ingested is not well understood. We investigated which sensory trait(s) of a beverage influence the thirst quenching efficacy of ingested liquids and the perceived amount ingested. We deprived healthy individuals of liquid and food overnight (> 12 hours) to make them thirsty. After asking them to drink a fixed volume (400 mL) of an experimental beverage presenting one or two specific sensory traits, we determined the volume ingested of additional plain, ‘still’, room temperature water to assess their residual thirst and, by extension, the thirst-quenching properties of the experimental beverage. In a second study, participants were asked to drink the experimental beverages from an opaque container through a straw and estimate the volume ingested. We found that among several oro-sensory traits, the perceptions of coldness, induced either by cold water (thermally) or by l-menthol (chemically), and the feeling of oral carbonation, strongly enhance the thirst quenching properties of a beverage in water-deprived humans (additional water intake after the 400 ml experimental beverage was reduced by up to 50%). When blinded to the volume of liquid consumed, individual’s estimation of ingested volume is increased (~22%) by perceived oral cold and carbonation, raising the idea that cold and perhaps CO2 induced-irritation sensations are included in how we normally encode water in the mouth and how we estimate the quantity of volume swallowed. These findings have implications for addressing inadequate hydration state in populations such as the elderly. PMID:27685093

NOAA Atlas 14: Updated Precipitation Frequency Estimates for the United States

NASA Astrophysics Data System (ADS)

Pavlovic, S.; Perica, S.; Martin, D.; Roy, I.; StLaurent, M.; Trypaluk, C.; Unruh, D.; Yekta, M.; Bonnin, G. M.

2013-12-01

NOAA Atlas 14 precipitation frequency estimates, developed by the National Weather Service's Hydrometeorological Design Studies Center, serve as the de-facto standards for a wide variety of design and planning activities under federal, state, and local regulations. Precipitation frequency estimates are used in the design of drainage for highways, culverts, bridges, parking lots, as well as in sizing sewer and stormwater infrastructure. Water resources engineers use them to estimate the amount of runoff, to estimate the volume of detention basins and size detention-basin outlet structures, and to estimate the volume of sediment or the amount of erosion. They are also used by floodplain managers to delineate floodplains and regulate the development in floodplains, which is crucial for all communities in the National Flood Insurance Program. Hydrometeorological Design Studies Center now provides more than 35,000 downloads per month to its Precipitation Frequency Data Server. Precipitation frequency estimates are often used in engineering design without any understanding how these estimates have been developed or without any understanding of the uncertainties associated with these estimates. This presentation will describe novel tools and techniques that have being developed in the last years to determine precipitation frequency estimates in NOAA Atlas 14. Particular attention will be given to the regional frequency analysis approach based on L-moment statistics calculated from annual maximum series, selected statistics obtained in determining and parameterizing the probability distribution functions, and the potential implication for engineering design of recently published estimates.

NOAA Atlas 14: Updated Precipitation Frequency Estimates for the United States

NASA Astrophysics Data System (ADS)

Pavlovic, S.; Perica, S.; Martin, D.; Roy, I.; StLaurent, M.; Trypaluk, C.; Unruh, D.; Yekta, M.; Bonnin, G. M.

2011-12-01

NOAA Atlas 14 precipitation frequency estimates, developed by the National Weather Service's Hydrometeorological Design Studies Center, serve as the de-facto standards for a wide variety of design and planning activities under federal, state, and local regulations. Precipitation frequency estimates are used in the design of drainage for highways, culverts, bridges, parking lots, as well as in sizing sewer and stormwater infrastructure. Water resources engineers use them to estimate the amount of runoff, to estimate the volume of detention basins and size detention-basin outlet structures, and to estimate the volume of sediment or the amount of erosion. They are also used by floodplain managers to delineate floodplains and regulate the development in floodplains, which is crucial for all communities in the National Flood Insurance Program. Hydrometeorological Design Studies Center now provides more than 35,000 downloads per month to its Precipitation Frequency Data Server. Precipitation frequency estimates are often used in engineering design without any understanding how these estimates have been developed or without any understanding of the uncertainties associated with these estimates. This presentation will describe novel tools and techniques that have being developed in the last years to determine precipitation frequency estimates in NOAA Atlas 14. Particular attention will be given to the regional frequency analysis approach based on L-moment statistics calculated from annual maximum series, selected statistics obtained in determining and parameterizing the probability distribution functions, and the potential implication for engineering design of recently published estimates.

Comparative analysis of two methods for measuring sales volumes during malaria medicine outlet surveys.

PubMed

Patouillard, Edith; Kleinschmidt, Immo; Hanson, Kara; Pok, Sochea; Palafox, Benjamin; Tougher, Sarah; O'Connell, Kate; Goodman, Catherine

2013-09-05

There is increased interest in using commercial providers for improving access to quality malaria treatment. Understanding their current role is an essential first step, notably in terms of the volume of diagnostics and anti-malarials they sell. Sales volume data can be used to measure the importance of different provider and product types, frequency of parasitological diagnosis and impact of interventions. Several methods for measuring sales volumes are available, yet all have methodological challenges and evidence is lacking on the comparability of different methods. Using sales volume data on anti-malarials and rapid diagnostic tests (RDTs) for malaria collected through provider recall (RC) and retail audits (RA), this study measures the degree of agreement between the two methods at wholesale and retail commercial providers in Cambodia following the Bland-Altman approach. Relative strengths and weaknesses of the methods were also investigated through qualitative research with fieldworkers. A total of 67 wholesalers and 107 retailers were sampled. Wholesale sales volumes were estimated through both methods for 62 anti-malarials and 23 RDTs and retail volumes for 113 anti-malarials and 33 RDTs. At wholesale outlets, RA estimates for anti-malarial sales were on average higher than RC estimates (mean difference of four adult equivalent treatment doses (95% CI 0.6-7.2)), equivalent to 30% of mean sales volumes. For RDTs at wholesalers, the between-method mean difference was not statistically significant (one test, 95% CI -6.0-4.0). At retail outlets, between-method differences for both anti-malarials and RDTs increased with larger volumes being measured, so mean differences were not a meaningful measure of agreement between the methods. Qualitative research revealed that in Cambodia where sales volumes are small, RC had key advantages: providers were perceived to remember more easily their sales volumes and find RC less invasive; fieldworkers found it more convenient; and it was cheaper to implement than RA. Both RA and RC had implementation challenges and were prone to data collection errors. Choice of empirical methods is likely to have important implications for data quality depending on the study context.

Comparative analysis of two methods for measuring sales volumes during malaria medicine outlet surveys

PubMed Central

2013-01-01

Background There is increased interest in using commercial providers for improving access to quality malaria treatment. Understanding their current role is an essential first step, notably in terms of the volume of diagnostics and anti-malarials they sell. Sales volume data can be used to measure the importance of different provider and product types, frequency of parasitological diagnosis and impact of interventions. Several methods for measuring sales volumes are available, yet all have methodological challenges and evidence is lacking on the comparability of different methods. Methods Using sales volume data on anti-malarials and rapid diagnostic tests (RDTs) for malaria collected through provider recall (RC) and retail audits (RA), this study measures the degree of agreement between the two methods at wholesale and retail commercial providers in Cambodia following the Bland-Altman approach. Relative strengths and weaknesses of the methods were also investigated through qualitative research with fieldworkers. Results A total of 67 wholesalers and 107 retailers were sampled. Wholesale sales volumes were estimated through both methods for 62 anti-malarials and 23 RDTs and retail volumes for 113 anti-malarials and 33 RDTs. At wholesale outlets, RA estimates for anti-malarial sales were on average higher than RC estimates (mean difference of four adult equivalent treatment doses (95% CI 0.6-7.2)), equivalent to 30% of mean sales volumes. For RDTs at wholesalers, the between-method mean difference was not statistically significant (one test, 95% CI −6.0-4.0). At retail outlets, between-method differences for both anti-malarials and RDTs increased with larger volumes being measured, so mean differences were not a meaningful measure of agreement between the methods. Qualitative research revealed that in Cambodia where sales volumes are small, RC had key advantages: providers were perceived to remember more easily their sales volumes and find RC less invasive; fieldworkers found it more convenient; and it was cheaper to implement than RA. Discussion/conclusions Both RA and RC had implementation challenges and were prone to data collection errors. Choice of empirical methods is likely to have important implications for data quality depending on the study context. PMID:24010526

Effect of immersion on lung capacities and volumes: implications for the densitometric estimation of relative body fat.

PubMed

Withers, R T; Hamdorf, P A

1989-01-01

Immersion of 18 male subjects in water caused a 20.4% (787 ml) increase (P less than 0.05) in the mean inspiratory capacity (IC) whereas there were no changes (P greater than 0.05) in tidal volume (VT) and the frequency of respiration. All the means for the other pulmonary variables decreased (P less than 0.05) by varying amounts: total lung capacity (TLC) = 8.4% (599 ml), vital capacity (VC) = 5.5% (308 ml), functional residual capacity (FRC) = 42.6% (1386 ml), expiratory reserve volume (ERV) = 61.9% (1095 ml) and residual volume (RV) = 19.7% (292 ml). Variation of only the RV in the body density (BD) formula from which the percentage body fat (%BF) is estimated resulted in a significantly (P less than 0.05) lower mean of 15.2% BF for the RV in air (means = 1482 ml) compared with that of 17.1% BF for the RV in water (means = 1190 ml). All but one of the subjects exhibited a smaller RV in water than in air; the six largest differences were equivalent to 2.4-5.1% BF. These results indicate that the net effect of the hydrostatic pressure (decreases RV), pulmonary vascular engorgement (decreases RV) and diminished compliance (increases RV) is to reduce the ventilated RV. It is therefore advisable to measure the RV when the subject is immersed in order to minimize error in the determination of BD and hence the estimation of % BF.

Allometry of visceral organs in living amniotes and its implications for sauropod dinosaurs

PubMed Central

Franz, Ragna; Hummel, Jürgen; Kienzle, Ellen; Kölle, Petra; Gunga, Hanns-Christian; Clauss, Marcus

2009-01-01

Allometric equations are often used to extrapolate traits in animals for which only body mass estimates are known, such as dinosaurs. One important decision can be whether these equations should be based on mammal, bird or reptile data. To address whether this choice will have a relevant influence on reconstructions, we compared allometric equations for birds and mammals from the literature to those for reptiles derived from both published and hitherto unpublished data. Organs studied included the heart, kidneys, liver and gut, as well as gut contents. While the available data indicate that gut content mass does not differ between the clades, the organ masses for reptiles are generally lower than those for mammals and birds. In particular, gut tissue mass is significantly lower in reptiles. When applying the results in the reconstruction of a sauropod dinosaur, the estimated volume of the coelomic cavity greatly exceeds the estimated volume of the combined organ masses, irrespective of the allometric equation used. Therefore, substantial deviation of sauropod organ allometry from that of the extant vertebrates can be allowed conceptually. Extrapolations of retention times from estimated gut contents mass and food intake do not suggest digestive constraints on sauropod dinosaur body size. PMID:19324837

Joint Estimation of Effective Brain Wave Activation Modes Using EEG/MEG Sensor Arrays and Multimodal MRI Volumes.

PubMed

Galinsky, Vitaly L; Martinez, Antigona; Paulus, Martin P; Frank, Lawrence R

2018-04-13

In this letter, we present a new method for integration of sensor-based multifrequency bands of electroencephalography and magnetoencephalography data sets into a voxel-based structural-temporal magnetic resonance imaging analysis by utilizing the general joint estimation using entropy regularization (JESTER) framework. This allows enhancement of the spatial-temporal localization of brain function and the ability to relate it to morphological features and structural connectivity. This method has broad implications for both basic neuroscience research and clinical neuroscience focused on identifying disease-relevant biomarkers by enhancing the spatial-temporal resolution of the estimates derived from current neuroimaging modalities, thereby providing a better picture of the normal human brain in basic neuroimaging experiments and variations associated with disease states.

Chronic Kidney Disease Is Associated With White Matter Hyperintensity Volume

PubMed Central

Khatri, Minesh; Wright, Clinton B.; Nickolas, Thomas L.; Yoshita, Mitsuhiro; Paik, Myunghee C.; Kranwinkel, Grace; Sacco, Ralph L.; DeCarli, Charles

2010-01-01

Background and Purpose White matter hyperintensities have been associated with increased risk of stroke, cognitive decline, and dementia. Chronic kidney disease is a risk factor for vascular disease and has been associated with inflammation and endothelial dysfunction, which have been implicated in the pathogenesis of white matter hyperintensities. Few studies have explored the relationship between chronic kidney disease and white matter hyperintensities. Methods The Northern Manhattan Study is a prospective, community-based cohort of which a subset of stroke-free participants underwent MRIs. MRIs were analyzed quantitatively for white matter hyperintensities volume, which was log-transformed to yield a normal distribution (log-white matter hyperintensity volume). Kidney function was modeled using serum creatinine, the Cockcroft-Gault formula for creatinine clearance, and the Modification of Diet in Renal Disease formula for estimated glomerular filtration rate. Creatinine clearance and estimated glomerular filtration rate were trichotomized to 15 to 60 mL/min, 60 to 90 mL/min, and >90 mL/min (reference). Linear regression was used to measure the association between kidney function and log-white matter hyperintensity volume adjusting for age, gender, race–ethnicity, education, cardiac disease, diabetes, homocysteine, and hypertension. Results Baseline data were available on 615 subjects (mean age 70 years, 60% women, 18% whites, 21% blacks, 62% Hispanics). In multivariate analysis, creatinine clearance 15 to 60 mL/min was associated with increased log-white matter hyperintensity volume (β 0.322; 95% CI, 0.095 to 0.550) as was estimated glomerular filtration rate 15 to 60 mL/min (β 0.322; 95% CI, 0.080 to 0.564). Serum creatinine, per 1-mg/dL increase, was also positively associated with log-white matter hyperintensity volume (β 1.479; 95% CI, 1.067 to 2.050). Conclusions The association between moderate–severe chronic kidney disease and white matter hyperintensity volume highlights the growing importance of kidney disease as a possible determinant of cerebrovascular disease and/or as a marker of microangiopathy. PMID:17962588

Validity of VO(2 max) in Predicting Blood Volume: Implications for the Effect of Fitness on Aging

DTIC Science & Technology

2000-09-01

not unexpected since an expansion of BV typically accompanies an increase in V̇O2 max with exercise train- ing (9). However, other investigations...for the collection of information is estimated to average 1 hour per response , including the time for reviewing instructions, searching existing data...CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT SAR 18. NUMBER OF PAGES 8 19a. NAME OF RESPONSIBLE PERSON a. REPORT unclassified b. ABSTRACT

The 1868 Hayward fault, California, earthquake: Implications for earthquake scaling relations on partially creeping faults

USGS Publications Warehouse

Hough, Susan E.; Martin, Stacey

2015-01-01

The 21 October 1868 Hayward, California, earthquake is among the best-characterized historical earthquakes in California. In contrast to many other moderate-to-large historical events, the causative fault is clearly established. Published magnitude estimates have been fairly consistent, ranging from 6.8 to 7.2, with 95% confidence limits including values as low as 6.5. The magnitude is of particular importance for assessment of seismic hazard associated with the Hayward fault and, more generally, to develop appropriate magnitude–rupture length scaling relations for partially creeping faults. The recent reevaluation of archival accounts by Boatwright and Bundock (2008), together with the growing volume of well-calibrated intensity data from the U.S. Geological Survey “Did You Feel It?” (DYFI) system, provide an opportunity to revisit and refine the magnitude estimate. In this study, we estimate the magnitude using two different methods that use DYFI data as calibration. Both approaches yield preferred magnitude estimates of 6.3–6.6, assuming an average stress drop. A consideration of data limitations associated with settlement patterns increases the range to 6.3–6.7, with a preferred estimate of 6.5. Although magnitude estimates for historical earthquakes are inevitably uncertain, we conclude that, at a minimum, a lower-magnitude estimate represents a credible alternative interpretation of available data. We further discuss implications of our results for probabilistic seismic-hazard assessment from partially creeping faults.

Application of Control Volume Analysis to Cerebrospinal Fluid Dynamics

NASA Astrophysics Data System (ADS)

Wei, Timothy; Cohen, Benjamin; Anor, Tomer; Madsen, Joseph

2011-11-01

Hydrocephalus is among the most common birth defects and may not be prevented nor cured. Afflicted individuals face serious issues, which at present are too complicated and not well enough understood to treat via systematic therapies. This talk outlines the framework and application of a control volume methodology to clinical Phase Contrast MRI data. Specifically, integral control volume analysis utilizes a fundamental, fluid dynamics methodology to quantify intracranial dynamics within a precise, direct, and physically meaningful framework. A chronically shunted, hydrocephalic patient in need of a revision procedure was used as an in vivo case study. Magnetic resonance velocity measurements within the patient's aqueduct were obtained in four biomedical state and were analyzed using the methods presented in this dissertation. Pressure force estimates were obtained, showing distinct differences in amplitude, phase, and waveform shape for different intracranial states within the same individual. Thoughts on the physiological and diagnostic research and development implications/opportunities will be presented.

Detection and volume estimation of embolic air in the middle cerebral artery using transcranial Doppler sonography.

PubMed

Bunegin, L; Wahl, D; Albin, M S

1994-03-01

Cerebral embolism has been implicated in the development of cognitive and neurological deficits following bypass surgery. This study proposes methodology for estimating cerebral air embolus volume using transcranial Doppler sonography. Transcranial Doppler audio signals of air bubbles in the middle cerebral artery obtained from in vivo experiments were subjected to a fast-Fourier transform analysis. Audio segments when no air was present as well as artifact resulting from electrocautery and sensor movement were also subjected to fast-Fourier transform analysis. Spectra were compared, and frequency and power differences were noted and used for development of audio band-pass filters for isolation of frequencies associated with air emboli. In a bench model of the middle cerebral artery circulation, repetitive injections of various air volumes between 0.5 and 500 microL were made. Transcranial Doppler audio output was band-pass filtered, acquired digitally, then subjected to a fast-Fourier transform power spectrum analysis and power spectrum integration. A linear least-squares correlation was performed on the data. Fast-Fourier transform analysis of audio segments indicated that frequencies between 250 and 500 Hz are consistently dominant in the spectrum when air emboli are present. Background frequencies appear to be below 240 Hz, and artifact resulting from sensor movement and electrocautery appears to be below 300 Hz. Data from the middle cerebral artery model filtered through a 307- to 450-Hz band-pass filter yielded a linear relation between emboli volume and the integrated value of the power spectrum near 40 microL. Detection of emboli less than 0.5 microL was inconsistent, and embolus volumes greater than 40 microL were indistinguishable from one another. The preliminary technique described in this study may represent a starting point from which automated detection and volume estimation of cerebral emboli might be approached.

A comparison of ambient casino sound and music: effects on dissociation and on perceptions of elapsed time while playing slot machines.

PubMed

Noseworthy, Theodore J; Finlay, Karen

2009-09-01

This research examined the effects of a casino's auditory character on estimates of elapsed time while gambling. More specifically, this study varied whether the sound heard while gambling was ambient casino sound alone or ambient casino sound accompanied by music. The tempo and volume of both the music and ambient sound were varied to manipulate temporal engagement and introspection. One hundred and sixty (males = 91) individuals played slot machines in groups of 5-8, after which they provided estimates of elapsed time. The findings showed that the typical ambient casino auditive environment, which characterizes the majority of gaming venues, promotes understated estimates of elapsed duration of play. In contrast, when music is introduced into the ambient casino environment, it appears to provide a cue of interval from which players can more accurately reconstruct elapsed duration of play. This is particularly the case when the tempo of the music is slow and the volume is high. Moreover, the confidence with which time estimates are held (as reflected by latency of response) is higher in an auditive environment with music than in an environment that is comprised of ambient casino sounds alone. Implications for casino management are discussed.

River suspended sediment estimation by climatic variables implication: Comparative study among soft computing techniques

NASA Astrophysics Data System (ADS)

Kisi, Ozgur; Shiri, Jalal

2012-06-01

Estimating sediment volume carried by a river is an important issue in water resources engineering. This paper compares the accuracy of three different soft computing methods, Artificial Neural Networks (ANNs), Adaptive Neuro-Fuzzy Inference System (ANFIS), and Gene Expression Programming (GEP), in estimating daily suspended sediment concentration on rivers by using hydro-meteorological data. The daily rainfall, streamflow and suspended sediment concentration data from Eel River near Dos Rios, at California, USA are used as a case study. The comparison results indicate that the GEP model performs better than the other models in daily suspended sediment concentration estimation for the particular data sets used in this study. Levenberg-Marquardt, conjugate gradient and gradient descent training algorithms were used for the ANN models. Out of three algorithms, the Conjugate gradient algorithm was found to be better than the others.

Associations of hypoosmotic swelling test, relative sperm volume shift, aquaporin7 mRNA abundance and bull fertility estimates.

PubMed

Kasimanickam, R K; Kasimanickam, V R; Arangasamy, A; Kastelic, J P

2017-02-01

Mammalian sperm are exposed to a natural hypoosmotic environment during male-to-female reproductive tract transition; although this activates sperm motility in vivo, excessive swelling can harm sperm structure and function. Aquaporins (AQPs) is a family of membrane-channel proteins implicated in sperm osmoregulation. The objective was to determine associations among relative sperm volume shift, hypoosmotic swelling test (HOST), sperm aquaporin (AQP) 7 mRNA abundances, and sire conception rate (SCR; fertility estimate) in Holstein bulls at a commercial artificial insemination center. Three or four sires for each full point SCR score from -4 to +4 were included. Each SCR estimate for study bulls (N = 30) was based on > 500 services (mean ± SEM) of 725 ± 13 services/sire). Sperm from a single collection day (two ejaculates) from these commercial Holstein bulls were used. Relative mRNA expression of AQP7 in sperm was determined by polymerase chain reaction. Mean relative sperm volume shift and percentage of sperm reacted in a HOST (% HOST) were determined (400 sperm per bull) after incubating in isoosmotic (300 mOsm/kg) and hypoosmotic (100 mOsm/kg) solutions for 30 min. There was no correlation between %HOST and SCR (r = 0.28 P > 0.1). However, there was a positive correlation between relative sperm volume shift and SCR (r = 0.65, P < 0.05). Furthermore, AQP7 mRNA abundance was positively correlated to both relative volume shift (r = 0.73; P < 0.05) and to SCR (r = 0.67; P < 0.05). The mRNA expressions of AQP7 and relative sperm volume shift differed (P < 0.05) among low- (<2 SCR), average- (-2 to +2) and high- (>2) fertility sire groups. In conclusion, bulls with higher SCR had significantly greater AQP7 mRNA abundance in frozen-thawed sperm. This plausibly contributed to greater regulation of sperm volume shift, which apparently conferred protection from detrimental swelling and impaired functions. Copyright © 2016 Elsevier Inc. All rights reserved.

What controls the maximum magnitude of injection-induced earthquakes?

NASA Astrophysics Data System (ADS)

Eaton, D. W. S.

2017-12-01

Three different approaches for estimation of maximum magnitude are considered here, along with their implications for managing risk. The first approach is based on a deterministic limit for seismic moment proposed by McGarr (1976), which was originally designed for application to mining-induced seismicity. This approach has since been reformulated for earthquakes induced by fluid injection (McGarr, 2014). In essence, this method assumes that the upper limit for seismic moment release is constrained by the pressure-induced stress change. A deterministic limit is given by the product of shear modulus and the net injected fluid volume. This method is based on the assumptions that the medium is fully saturated and in a state of incipient failure. An alternative geometrical approach was proposed by Shapiro et al. (2011), who postulated that the rupture area for an induced earthquake falls entirely within the stimulated volume. This assumption reduces the maximum-magnitude problem to one of estimating the largest potential slip surface area within a given stimulated volume. Finally, van der Elst et al. (2016) proposed that the maximum observed magnitude, statistically speaking, is the expected maximum value for a finite sample drawn from an unbounded Gutenberg-Richter distribution. These three models imply different approaches for risk management. The deterministic method proposed by McGarr (2014) implies that a ceiling on the maximum magnitude can be imposed by limiting the net injected volume, whereas the approach developed by Shapiro et al. (2011) implies that the time-dependent maximum magnitude is governed by the spatial size of the microseismic event cloud. Finally, the sample-size hypothesis of Van der Elst et al. (2016) implies that the best available estimate of the maximum magnitude is based upon observed seismicity rate. The latter two approaches suggest that real-time monitoring is essential for effective management of risk. A reliable estimate of maximum plausible magnitude would clearly be beneficial for quantitative risk assessment of injection-induced seismicity.

Airborne vs. Inventory Measurements of Methane Emissions in the Alberta Upstream Oil and Gas Sector

NASA Astrophysics Data System (ADS)

Johnson, M.; Tyner, D. R.; Conley, S.; Schwietzke, S.; Zavala Araiza, D.

2017-12-01

Airborne measurements of methane emission rates were directly compared with detailed, spatially-resolved inventory estimates for different oil and gas production regions in Alberta, Canada. For a 50 km × 50 km region near Red Deer, Alberta, containing 2700 older gas and oil wells, measured methane emissions were 16 times higher than reported venting and flaring volumes would suggest, but consistent with regional inventory estimates (which include estimates for additional emissions from pneumatic equipment, fugitive leaks, gas migration, etc.). This result highlights how 94% of methane emissions in this region are attributable to sources missing from current reporting requirements. The comparison was even more stark for a 60 km × 60 km region near Lloydminster, dominated by 2300 cold heavy oil with sand (CHOPS) production sites. Aircraft measured methane emissions in this region were 5 times larger than that expected from reported venting and flaring volumes, and more than 3 times greater than regional inventory estimates. This significant discrepancy is most likely attributable to underreported intentional venting of casing gas at CHOPS sites, which is generally estimated based on the product of the measured produced oil volume and an assumed gas to oil ratio (GOR). GOR values at CHOPS sites can be difficult to measure and can be notoriously variable in time. Considering the implications for other CHOPS sites across Alberta only, the present results suggest that total reported venting in Alberta is low by a factor of 2.4 (range of 2.0-2.7) and total methane emissions from the conventional oil and gas sector (excluding mined oil sands) are likely at least 25-41% greater than currently estimated. This work reveals critical gaps in current measurement and reporting, while strongly supporting the need for urgent mitigation efforts in the context of newly proposed federal methane regulations in Canada, and separate regulatory development efforts in the province of Alberta.

Constraining Runoff Source Fraction Contributions from Alpine Glaciers through the Combined Application of Geochemical Proxies and Bayesian Monte Carlo Isotope Mixing Models

NASA Astrophysics Data System (ADS)

Arendt, C. A.; Aciego, S.; Hetland, E.

2015-12-01

Processes that drive glacial ablation directly impact surrounding ecosystems and communities that are dependent on glacial meltwater as a freshwater reservoir: crucially, freshwater runoff from alpine and Arctic glaciers has large implications for watershed ecosystems and contingent economies. Furthermore, glacial hydrology processes are a complex and fundamental part of understanding high-latitude environments in the modern and predicting how they might change in the future. Specifically, developing better estimates of the origin of freshwater discharge, as well as the duration and amplitude of extreme melting and precipitation events, could provide crucial constraints on these processes and allow for glacial watershed systems to be modeled more effectively. In order to investigate the universality of the temporal and spatial melt relationships that exist in glacial systems, I investigate the isotopic composition of glacial meltwater and proximal seawater including stable isotopes δ18O and δD, which have been measured in glacial water samples I collected from the alpine Athabasca Glacier in the Canadian Rockies. This abstract is focused on extrapolating the relative contributions of meltwater sources - snowmelt, ice melt, and summer precipitation - using a coupled statistical-chemical model (Arendt et al., 2015). I apply δ18O and δD measurements of Athabasca Glacier subglacial water samples to a Bayesian Monte Carlo (BMC) estimation scheme. Importantly, this BMC model also assesses the uncertainties associated with these meltwater fractional contribution estimations, which provides an assessment of how well the system is constrained. By defining the proportion of overall melt that is coming from snow versus ice using stable isotopes, the volume of water generated by ablation can be calculated. This water volume has two important implications. First, communities that depend on glacial water for aquifer recharge can start assessing future water resources, as glacial decline will make snowmelt the dominant water reservoir. Second, the calculated source fraction water volumes are a starting point for additional geochemical models to investigate water storage within the subglacial hydrological network.

Dust Emissions, Transport, and Deposition Simulated with the NASA Finite-Volume General Circulation Model

NASA Technical Reports Server (NTRS)

Colarco, Peter; daSilva, Arlindo; Ginoux, Paul; Chin, Mian; Lin, S.-J.

2003-01-01

Mineral dust aerosols have radiative impacts on Earth's atmosphere, have been implicated in local and regional air quality issues, and have been identified as vectors for transporting disease pathogens and bringing mineral nutrients to terrestrial and oceanic ecosystems. We present for the first time dust simulations using online transport and meteorological analysis in the NASA Finite-Volume General Circulation Model (FVGCM). Our dust formulation follows the formulation in the offline Georgia Institute of Technology-Goddard Global Ozone Chemistry Aerosol Radiation and Transport Model (GOCART) using a topographical source for dust emissions. We compare results of the FVGCM simulations with GOCART, as well as with in situ and remotely sensed observations. Additionally, we estimate budgets of dust emission and transport into various regions.

Multi-Scale Computational Models for Electrical Brain Stimulation

PubMed Central

Seo, Hyeon; Jun, Sung C.

2017-01-01

Electrical brain stimulation (EBS) is an appealing method to treat neurological disorders. To achieve optimal stimulation effects and a better understanding of the underlying brain mechanisms, neuroscientists have proposed computational modeling studies for a decade. Recently, multi-scale models that combine a volume conductor head model and multi-compartmental models of cortical neurons have been developed to predict stimulation effects on the macroscopic and microscopic levels more precisely. As the need for better computational models continues to increase, we overview here recent multi-scale modeling studies; we focused on approaches that coupled a simplified or high-resolution volume conductor head model and multi-compartmental models of cortical neurons, and constructed realistic fiber models using diffusion tensor imaging (DTI). Further implications for achieving better precision in estimating cellular responses are discussed. PMID:29123476

Serum vitamin D and hippocampal gray matter volume in schizophrenia.

PubMed

Shivakumar, Venkataram; Kalmady, Sunil V; Amaresha, Anekal C; Jose, Dania; Narayanaswamy, Janardhanan C; Agarwal, Sri Mahavir; Joseph, Boban; Venkatasubramanian, Ganesan; Ravi, Vasanthapuram; Keshavan, Matcheri S; Gangadhar, Bangalore N

2015-08-30

Disparate lines of evidence including epidemiological and case-control studies have increasingly implicated vitamin D in the pathogenesis of schizophrenia. Vitamin D deficiency can lead to dysfunction of the hippocampus--a brain region hypothesized to be critically involved in schizophrenia. In this study, we examined for potential association between serum vitamin D level and hippocampal gray matter volume in antipsychotic-naïve or antipsychotic-free schizophrenia patients (n = 35). Serum vitamin D level was estimated using 25-OH vitamin D immunoassay. Optimized voxel-based morphometry was used to analyze 3-Tesla magnetic resonance imaging (MRI) (1-mm slice thickness). Ninety-seven percent of the schizophrenia patients (n = 34) had sub-optimal levels of serum vitamin D (83%, deficiency; 14%, insufficiency). A significant positive correlation was seen between vitamin D and regional gray matter volume in the right hippocampus after controlling for age, years of education and total intracranial volume (Montreal Neurological Institute (MNI) coordinates: x = 35, y = -18, z = -8; t = 4.34 pFWE(Corrected) = 0.018). These observations support a potential role of vitamin D deficiency in mediating hippocampal volume deficits, possibly through neurotrophic, neuroimmunomodulatory and glutamatergic effects. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Each procedure matters: threshold for surgeon volume to minimize complications and decrease cost associated with adrenalectomy.

PubMed

Anderson, Kevin L; Thomas, Samantha M; Adam, Mohamed A; Pontius, Lauren N; Stang, Michael T; Scheri, Randall P; Roman, Sanziana A; Sosa, Julie A

2018-01-01

An association has been suggested between increasing surgeon volume and improved patient outcomes, but a threshold has not been defined for what constitutes a "high-volume" adrenal surgeon. Adult patients who underwent adrenalectomy by an identifiable surgeon between 1998-2009 were selected from the Healthcare Cost and Utilization Project National Inpatient Sample. Logistic regression modeling with restricted cubic splines was utilized to estimate the association between annual surgeon volume and complication rates in order to identify a volume threshold. A total of 3,496 surgeons performed adrenalectomies on 6,712 patients; median annual surgeon volume was 1 case. After adjustment, the likelihood of experiencing a complication decreased with increasing annual surgeon volume up to 5.6 cases (95% confidence interval, 3.27-5.96). After adjustment, patients undergoing resection by low-volume surgeons (<6 cases/year) were more likely to experience complications (odds ratio 1.71, 95% confidence interval, 1.27-2.31, P = .005), have a greater hospital stay (relative risk 1.46, 95% confidence interval, 1.25-1.70, P = .003), and at increased cost (+26.2%, 95% confidence interval, 12.6-39.9, P = .02). This study suggests that an annual threshold of surgeon volume (≥6 cases/year) that is associated with improved patient outcomes and decreased hospital cost. This volume threshold has implications for quality improvement, surgical referral and reimbursement, and surgical training. Copyright © 2017 Elsevier Inc. All rights reserved.

Direct volume estimation without segmentation

NASA Astrophysics Data System (ADS)

Zhen, X.; Wang, Z.; Islam, A.; Bhaduri, M.; Chan, I.; Li, S.

2015-03-01

Volume estimation plays an important role in clinical diagnosis. For example, cardiac ventricular volumes including left ventricle (LV) and right ventricle (RV) are important clinical indicators of cardiac functions. Accurate and automatic estimation of the ventricular volumes is essential to the assessment of cardiac functions and diagnosis of heart diseases. Conventional methods are dependent on an intermediate segmentation step which is obtained either manually or automatically. However, manual segmentation is extremely time-consuming, subjective and highly non-reproducible; automatic segmentation is still challenging, computationally expensive, and completely unsolved for the RV. Towards accurate and efficient direct volume estimation, our group has been researching on learning based methods without segmentation by leveraging state-of-the-art machine learning techniques. Our direct estimation methods remove the accessional step of segmentation and can naturally deal with various volume estimation tasks. Moreover, they are extremely flexible to be used for volume estimation of either joint bi-ventricles (LV and RV) or individual LV/RV. We comparatively study the performance of direct methods on cardiac ventricular volume estimation by comparing with segmentation based methods. Experimental results show that direct estimation methods provide more accurate estimation of cardiac ventricular volumes than segmentation based methods. This indicates that direct estimation methods not only provide a convenient and mature clinical tool for cardiac volume estimation but also enables diagnosis of cardiac diseases to be conducted in a more efficient and reliable way.

Scope of ACE in Australia. Volume 1: Implications for Improved Data Collection and Reporting [and] Volume 2: Analysis of Existing Information in National Education and Training Data Collection.

ERIC Educational Resources Information Center

Borthwick, J.; Knight, B.; Bender, A.; Loveder, P.

These two volumes provide information on the scope of adult and community education (ACE) in Australia and implications for improved data collection and reporting. Volume 1 begins with a glossary. Chapter 1 addresses project objectives and processes and methodology. Chapter 2 analyzes the scope and diversity of ACE in terms of what is currently…

High-Throughput 3-D Monitoring of Agricultural-Tree Plantations with Unmanned Aerial Vehicle (UAV) Technology

PubMed Central

Torres-Sánchez, Jorge; López-Granados, Francisca; Serrano, Nicolás; Arquero, Octavio; Peña, José M.

2015-01-01

The geometric features of agricultural trees such as canopy area, tree height and crown volume provide useful information about plantation status and crop production. However, these variables are mostly estimated after a time-consuming and hard field work and applying equations that treat the trees as geometric solids, which produce inconsistent results. As an alternative, this work presents an innovative procedure for computing the 3-dimensional geometric features of individual trees and tree-rows by applying two consecutive phases: 1) generation of Digital Surface Models with Unmanned Aerial Vehicle (UAV) technology and 2) use of object-based image analysis techniques. Our UAV-based procedure produced successful results both in single-tree and in tree-row plantations, reporting up to 97% accuracy on area quantification and minimal deviations compared to in-field estimations of tree heights and crown volumes. The maps generated could be used to understand the linkages between tree grown and field-related factors or to optimize crop management operations in the context of precision agriculture with relevant agro-environmental implications. PMID:26107174

High-Throughput 3-D Monitoring of Agricultural-Tree Plantations with Unmanned Aerial Vehicle (UAV) Technology.

PubMed

Torres-Sánchez, Jorge; López-Granados, Francisca; Serrano, Nicolás; Arquero, Octavio; Peña, José M

2015-01-01

The geometric features of agricultural trees such as canopy area, tree height and crown volume provide useful information about plantation status and crop production. However, these variables are mostly estimated after a time-consuming and hard field work and applying equations that treat the trees as geometric solids, which produce inconsistent results. As an alternative, this work presents an innovative procedure for computing the 3-dimensional geometric features of individual trees and tree-rows by applying two consecutive phases: 1) generation of Digital Surface Models with Unmanned Aerial Vehicle (UAV) technology and 2) use of object-based image analysis techniques. Our UAV-based procedure produced successful results both in single-tree and in tree-row plantations, reporting up to 97% accuracy on area quantification and minimal deviations compared to in-field estimations of tree heights and crown volumes. The maps generated could be used to understand the linkages between tree grown and field-related factors or to optimize crop management operations in the context of precision agriculture with relevant agro-environmental implications.

Biomarker progressions explain higher variability in stage-specific cognitive decline than baseline values in Alzheimer disease.

PubMed

Dodge, Hiroko H; Zhu, Jian; Harvey, Danielle; Saito, Naomi; Silbert, Lisa C; Kaye, Jeffrey A; Koeppe, Robert A; Albin, Roger L

2014-11-01

It is unknown which commonly used Alzheimer disease (AD) biomarker values-baseline or progression-best predict longitudinal cognitive decline. 526 subjects from the Alzheimer's Disease Neuroimaging Initiative (ADNI). ADNI composite memory and executive scores were the primary outcomes. Individual-specific slope of the longitudinal trajectory of each biomarker was first estimated. These estimates and observed baseline biomarker values were used as predictors of cognitive declines. Variability in cognitive declines explained by baseline biomarker values was compared with variability explained by biomarker progression values. About 40% of variability in memory and executive function declines was explained by ventricular volume progression among mild cognitive impairment patients. A total of 84% of memory and 65% of executive function declines were explained by fluorodeoxyglucose positron emission tomography (FDG-PET) score progression and ventricular volume progression, respectively, among AD patients. For most biomarkers, biomarker progressions explained higher variability in cognitive decline than biomarker baseline values. This has important implications for clinical trials targeted to modify AD biomarkers. Copyright © 2014 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Important influence of respiration on human R-R interval power spectra is largely ignored

NASA Technical Reports Server (NTRS)

Brown, T. E.; Beightol, L. A.; Koh, J.; Eckberg, D. L.

1993-01-01

Frequency-domain analyses of R-R intervals are used widely to estimate levels of autonomic neural traffic to the human heart. Because respiration modulates autonomic activity, we determined for nine healthy subjects the influence of breathing frequency and tidal volume on R-R interval power spectra (fast-Fourier transform method). We also surveyed published literature to determine current practices in this burgeoning field of scientific inquiry. Supine subjects breathed at rates of 6, 7.5, 10, 15, 17.1, 20, and 24 breaths/min and with nominal tidal volumes of 1,000 and 1,500 ml. R-R interval power at respiratory and low (0.06-0.14 Hz) frequencies declined significantly as breathing frequency increased. R-R interval power at respiratory frequencies was significantly greater at a tidal volume of 1,500 than 1,000 ml. Neither breathing frequency nor tidal volume influenced average R-R intervals significantly. Our review of studies reporting human R-R interval power spectra showed that 51% of the studies controlled respiratory rate, 11% controlled tidal volume, and 11% controlled both respiratory rate and tidal volume. The major implications of our analyses are that breathing parameters strongly influence low-frequency as well as respiratory frequency R-R interval power spectra and that this influence is largely ignored in published research.

Back to the future: estimating pre-injury brain volume in patients with traumatic brain injury.

PubMed

Ross, David E; Ochs, Alfred L; D Zannoni, Megan; Seabaugh, Jan M

2014-11-15

A recent meta-analysis by Hedman et al. allows for accurate estimation of brain volume changes throughout the life span. Additionally, Tate et al. showed that intracranial volume at a later point in life can be used to estimate reliably brain volume at an earlier point in life. These advancements were combined to create a model which allowed the estimation of brain volume just prior to injury in a group of patients with mild or moderate traumatic brain injury (TBI). This volume estimation model was used in combination with actual measurements of brain volume to test hypotheses about progressive brain volume changes in the patients. Twenty six patients with mild or moderate TBI were compared to 20 normal control subjects. NeuroQuant® was used to measure brain MRI volume. Brain volume after the injury (from MRI scans performed at t1 and t2) was compared to brain volume just before the injury (volume estimation at t0) using longitudinal designs. Groups were compared with respect to volume changes in whole brain parenchyma (WBP) and its 3 major subdivisions: cortical gray matter (GM), cerebral white matter (CWM) and subcortical nuclei+infratentorial regions (SCN+IFT). Using the normal control data, the volume estimation model was tested by comparing measured brain volume to estimated brain volume; reliability ranged from good to excellent. During the initial phase after injury (t0-t1), the TBI patients had abnormally rapid atrophy of WBP and CWM, and abnormally rapid enlargement of SCN+IFT. Rates of volume change during t0-t1 correlated with cross-sectional measures of volume change at t1, supporting the internal reliability of the volume estimation model. A logistic regression analysis using the volume change data produced a function which perfectly predicted group membership (TBI patients vs. normal control subjects). During the first few months after injury, patients with mild or moderate TBI have rapid atrophy of WBP and CWM, and rapid enlargement of SCN+IFT. The magnitude and pattern of the changes in volume may allow for the eventual development of diagnostic tools based on the volume estimation approach. Copyright © 2014 Elsevier Inc. All rights reserved.

Intraday return inefficiency and long memory in the volatilities of forex markets and the role of trading volume

NASA Astrophysics Data System (ADS)

Shahzad, Syed Jawad Hussain; Hernandez, Jose Areola; Hanif, Waqas; Kayani, Ghulam Mujtaba

2018-09-01

We investigate the dynamics of efficiency and long memory, and the impact of trading volume on the efficiency of returns and volatilities of four major traded currencies, namely, the EUR, GBP, CHF and JPY. We do so by implementing full sample and rolling window multifractal detrended fluctuation analysis (MF-DFA) and a quantile-on-quantile (QQ) approach. This paper sheds new light by employing high frequency (5-min interval) data spanning from Jan 1, 2007 to Dec 31, 2016. Realized volatilities are estimated using Andersen et al.'s (2001) measure, while the QQ method employed is drawn from Sim and Zhou (2015). We find evidence of higher efficiency levels in the JPY and CHF currency markets. The impact of trading volume on efficiency is only significant for the JPY and CHF currencies. The GBP currency appears to be the least efficient, followed by the EUR. Implications of the results are discussed.

Price trend analysis and its implications for the development of new medical technologies.

PubMed

Brown, Alan; Meenan, Brian J; Young, Terry P

2007-01-01

It is assumed that a company will only develop a new medical technology if it has evidence that it will provide returns that are greater than the investment required to develop that technology and bring it to the market. The price that can be commanded for the new products and the volumes of the products that are sold determine, in large measure, the returns that will be made on the initial investment. Estimating the sales volumes and prices of products are critical factors in decision making during product development. Once in the market prices are not static. Rather they are affected by a range of factors. This paper considers the effect that market experience, represented by cumulative volume of sales, has on prices. How quickly the price declines in response to experience is dependent on a number of factors. How price trends from products already in the market can be used to inform investment decisions of new products and technologies is described.

Study of safety implications for shuttle launched spacecraft using fluorinated oxidizers. Volume 2: Executive summary

NASA Technical Reports Server (NTRS)

1975-01-01

An abbreviated version of the conclusions dealing with the safety implications of using liquid fluorinated oxidizers on space shuttle launched spacecraft was presented. The complete version was presented in volume 1.

Doses and risks from the ingestion of Dounreay fuel fragments.

PubMed

Darley, P J; Charles, M W; Fell, T P; Harrison, J D

2003-01-01

The radiological implications of ingestion of nuclear fuel fragments present in the marine environment around Dounreay have been reassessed by using the Monte Carlo code MCNP to obtain improved estimates of the doses to target cells in the walls of the lower large intestine resulting from the passage of a fragment. The approach takes account of the reduction in dose due to attenuation within the intestinal wall and self-absorption of radiation in the fuel fragment itself. In addition, dose is calculated on the basis of a realistic estimate of the anatomical volume of the lumen, rather than being based on the average mass of the contents, as in the current ICRP model. Our best estimates of doses from the ingestion of the largest Dounreay particles are at least a factor of 30 lower than those predicted using the current ICRP model. The new ICRP model will address the issues raised here and provide improved estimates of dose.

Striatal volume predicts level of video game skill acquisition.

PubMed

Erickson, Kirk I; Boot, Walter R; Basak, Chandramallika; Neider, Mark B; Prakash, Ruchika S; Voss, Michelle W; Graybiel, Ann M; Simons, Daniel J; Fabiani, Monica; Gratton, Gabriele; Kramer, Arthur F

2010-11-01

Video game skills transfer to other tasks, but individual differences in performance and in learning and transfer rates make it difficult to identify the source of transfer benefits. We asked whether variability in initial acquisition and of improvement in performance on a demanding video game, the Space Fortress game, could be predicted by variations in the pretraining volume of either of 2 key brain regions implicated in learning and memory: the striatum, implicated in procedural learning and cognitive flexibility, and the hippocampus, implicated in declarative memory. We found that hippocampal volumes did not predict learning improvement but that striatal volumes did. Moreover, for the striatum, the volumes of the dorsal striatum predicted improvement in performance but the volumes of the ventral striatum did not. Both ventral and dorsal striatal volumes predicted early acquisition rates. Furthermore, this early-stage correlation between striatal volumes and learning held regardless of the cognitive flexibility demands of the game versions, whereas the predictive power of the dorsal striatal volumes held selectively for performance improvements in a game version emphasizing cognitive flexibility. These findings suggest a neuroanatomical basis for the superiority of training strategies that promote cognitive flexibility and transfer to untrained tasks.

A novel method for blood volume estimation using trivalent chromium in rabbit models.

PubMed

Baby, Prathap Moothamadathil; Kumar, Pramod; Kumar, Rajesh; Jacob, Sanu S; Rawat, Dinesh; Binu, V S; Karun, Kalesh M

2014-05-01

Blood volume measurement though important in management of critically ill-patients is not routinely estimated in clinical practice owing to labour intensive, intricate and time consuming nature of existing methods. The aim was to compare blood volume estimations using trivalent chromium [(51)Cr(III)] and standard Evans blue dye (EBD) method in New Zealand white rabbit models and establish correction-factor (CF). Blood volume estimation in 33 rabbits was carried out using EBD method and concentration determined using spectrophotometric assay followed by blood volume estimation using direct injection of (51)Cr(III). Twenty out of 33 rabbits were used to find CF by dividing blood volume estimation using EBD with blood volume estimation using (51)Cr(III). CF is validated in 13 rabbits by multiplying it with blood volume estimation values obtained using (51)Cr(III). The mean circulating blood volume of 33 rabbits using EBD was 142.02 ± 22.77 ml or 65.76 ± 9.31 ml/kg and using (51)Cr(III) was estimated to be 195.66 ± 47.30 ml or 89.81 ± 17.88 ml/kg. The CF was found to be 0.77. The mean blood volume of 13 rabbits measured using EBD was 139.54 ± 27.19 ml or 66.33 ± 8.26 ml/kg and using (51)Cr(III) with CF was 152.73 ± 46.25 ml or 71.87 ± 13.81 ml/kg (P = 0.11). The estimation of blood volume using (51)Cr(III) was comparable to standard EBD method using CF. With further research in this direction, we envisage human blood volume estimation using (51)Cr(III) to find its application in acute clinical settings.

Estimating antimalarial drugs consumption in Africa before the switch to artemisinin-based combination therapies (ACTs).

PubMed

Kindermans, Jean-Marie; Vandenbergh, Daniel; Vreeke, Ed; Olliaro, Piero; D'Altilia, Jean-Pierre

2007-07-10

Having reliable forecasts is critical now for producers, malaria-endemic countries and agencies in order to adapt production and procurement of the artemisinin-based combination treatments (ACTs), the new first-line treatments of malaria. There is no ideal method to quantify drug requirements for malaria. Morbidity data give uncertain estimations. This study uses drug consumption to provide elements to help estimate quantities and financial requirements of ACTs. The consumption of chloroquine, sulphadoxine/pyrimethamine and quinine both through the private and public sector was assessed in five sub-Saharan Africa countries with different epidemiological patterns (Senegal, Rwanda, Tanzania, Malawi, Zimbabwe). From these data the number of adult treatments per capita was calculated and the volumes and financial implications derived for the whole of Africa. Identifying and obtaining data from the private sector was difficult. The quality of information on drug supply and distribution in countries must be improved. The number of adult treatments per capita and per year in the five countries ranged from 0.18 to 0.50. Current adult treatment prices for ACTs range US$ 1-1.8. Taking the upper range for both volumes and costs, the highest number of adult treatments consumed for Africa was estimated at 314.5 million, corresponding to an overall maximum annual need for financing ACT procurement of US$ 566.1 million. In reality, both the number of cases treated and the cost of treatment are likely to be lower (projections for the lowest consumption estimate with the least expensive ACT would require US $ 113 million per annum). There were substantial variations in the market share between public and private sources among these countries (the public sector share ranging from 98% in Rwanda to 33% in Tanzania). Additional studies are required to build a more robust methodology, and to assess current consumptions more accurately in order to better quantify volumes and finances for production and procurement of ACTs.

The 1984 Mauna Loa eruption and planetary geolgoy

NASA Technical Reports Server (NTRS)

Moore, Henry J.

1987-01-01

In planetary geology, lava flows on the Moon and Mars are commonly treated as relatively simple systems. Some of the complexities of actual lava flows are illustrated using the main flow system of the 1984 Mauna Loa eruption. The outline, brief narrative, and results given are based on a number of sources. The implications of the results to planetary geology are clear. Volume flow rates during an eruption depend, in part, on the volatile content of the lava. These differ from the volume flow rates calculated from post eruption flow dimensions and the duration of the eruption and from those using models that assume a constant density. Mass flow rates might be more appropriate because the masses of volatiles in lavas are usually small, but variable and sometimes unknown densities impose severe restrictions on mass estimates.

Clinical implications of pleural effusion in patients with acute type B aortic dissection.

PubMed

Yamada, Yoshihiro; Tanno, Jun; Nakano, Shintaro; Kasai, Takatoshi; Senbonmatsu, Takaaki; Nishimura, Shigeyuki

2016-11-01

Pleural effusion may complicate acute Stanford type B aortic dissection (ABAD). To identify the relationships between the quantity and side of the pleural effusion, biomarkers and outcomes in patients with ABAD. We undertook a retrospective review of 105 patients with ABAD. Their demographics, the data on admission and during hospital stay, the volume of pleural effusion calculated from the area on computed tomography images and clinical outcomes were analysed. The median estimated peak volume (median 6.7 days after onset) was 129 ml (63-192, range 26-514 ml) on the left and 11 ml (6-43, range 2-300 ml) on the right. On univariate analysis, the volume of bilateral effusions was associated with anaemia, hypoalbuminaemia and inflammatory markers, whereas the volume of left-sided effusions was associated with older age, low diastolic blood pressure and maximum aortic diameter. Multivariate analysis revealed that hypoalbuminaemia was independently associated with bilateral effusion volume ( P<0.001), while maximum aortic diameter was associated with left-sided effusion volume ( P=0.019). A greater volume of bilateral plural effusion was associated with longer intensive care unit stay. Larger bilateral pleural effusions in patients with ABAD were associated with hypoalbuminaemia and potentially with anaemia and inflammation, and may increase the length of intensive care unit stay. Left-sided effusion volume appears to be influenced by the nature of the aortic dilatation. Multiple mechanisms may underpin the development of pleural effusion in ABAD, and are likely to influence clinical outcomes.

Woody debris volume depletion through decay: implications for biomass and carbon accounting

USGS Publications Warehouse

Fraver, Shawn; Milo, Amy M.; Bradford, John B.; D'Amato, Anthony W.; Kenefic, Laura; Palik, Brian J.; Woodall, Christopher W.; Brissette, John

2013-01-01

Woody debris decay rates have recently received much attention because of the need to quantify temporal changes in forest carbon stocks. Published decay rates, available for many species, are commonly used to characterize deadwood biomass and carbon depletion. However, decay rates are often derived from reductions in wood density through time, which when used to model biomass and carbon depletion are known to underestimate rate loss because they fail to account for volume reduction (changes in log shape) as decay progresses. We present a method for estimating changes in log volume through time and illustrate the method using a chronosequence approach. The method is based on the observation, confirmed herein, that decaying logs have a collapse ratio (cross-sectional height/width) that can serve as a surrogate for the volume remaining. Combining the resulting volume loss with concurrent changes in wood density from the same logs then allowed us to quantify biomass and carbon depletion for three study species. Results show that volume, density, and biomass follow distinct depletion curves during decomposition. Volume showed an initial lag period (log dimensions remained unchanged), even while wood density was being reduced. However, once volume depletion began, biomass loss (the product of density and volume depletion) occurred much more rapidly than density alone. At the temporal limit of our data, the proportion of the biomass remaining was roughly half that of the density remaining. Accounting for log volume depletion, as demonstrated in this study, provides a comprehensive characterization of deadwood decomposition, thereby improving biomass-loss and carbon-accounting models.

Guidelines for estimating volume, biomass, and smoke production for piled slash.

Treesearch

Colin C. Hardy

1998-01-01

Guidelines in the form of a six-step approach are provided for estimating volumes, oven-dry mass, consumption, and particulate matter emissions for piled logging debris. Seven stylized pile shapes and their associated geometric volume formulae are used to estimate gross pile volumes. The gross volumes are then reduced to net wood volume by applying an appropriate wood-...

Water storage in marine sediment and implications for inferences of past global ice volume

NASA Astrophysics Data System (ADS)

Ferrier, K.; Li, Q.; Pico, T.; Austermann, J.

2017-12-01

Changes in past sea level are of wide interest because they provide information on the sensitivity of ice sheets to climate change, and thus inform predictions of future sea-level change. Sea level changes are influenced by many processes, including the storage of water in sedimentary pore space. Here we use a recent extension of gravitationally self-consistent sea-level models to explore the effects of marine sedimentary water storage on the global seawater balance and inferences of past global ice volume. Our analysis suggests that sedimentary water storage can be a significant component of the global seawater budget over the 105-year timescales associated with glacial-interglacial cycles, and an even larger component over longer timescales. Estimates of global sediment fluxes to the oceans suggest that neglecting marine sedimentary water storage may produce meter-scale errors in estimates of peak global mean sea level equivalent (GMSL) during the Last Interglacial (LIG). These calculations show that marine sedimentary water storage can be a significant contributor to the overall effects of sediment redistribution on sea-level change, and that neglecting sedimentary water storage can lead to substantial errors in inferences of global ice volume at past interglacials. This highlights the importance of accounting for the influences of sediment fluxes and sedimentary water storage on sea-level change over glacial-interglacial timescales.

Lesion symptom map of cognitive-postural interference in multiple sclerosis.

PubMed

Ruggieri, Serena; Fanelli, Fulvia; Castelli, Letizia; Petsas, Nikolaos; De Giglio, Laura; Prosperini, Luca

2018-04-01

To investigate the disease-altered structure-function relationship underlying the cognitive-postural interference (CPI) phenomenon in multiple sclerosis (MS). We measured postural sway of 96 patients and 48 sex-/age-matched healthy controls by force platform in quiet standing (single-task (ST)) while performing the Stroop test (dual-task (DT)) to estimate the dual-task cost (DTC) of balance. In patient group, binary T2 and T1 lesion masks and their corresponding lesion volumes were obtained from magnetic resonance imaging (MRI) of brain. Normalized brain volume (NBV) was also estimated by SIENAX. Correlations between DTC and lesion location were determined by voxel-based lesion symptom mapping (VLSM) analyses. Patients had greater DTC than controls ( p < 0.001). Among whole brain MRI metrics, only T1 lesion volume correlated with DTC ( r = -0.27; p < 0.01). However, VLSM analysis did not reveal any association with DTC using T1 lesion masks. By contrast, we found clusters of T2 lesions in distinct anatomical regions (anterior and superior corona radiata, bilaterally) to be correlated with DTC ( p < 0.01 false discovery rate (FDR)-corrected). A multivariable stepwise regression model confirmed findings from VLSM analysis. NBV did not contribute to fit the model. Our findings suggest that the CPI phenomenon in MS can be explained by disconnection along specific areas implicated in task-switching abilities and divided attention.

A catastrophic flood caused by drainage of a caldera lake at Aniakchak Volcano, Alaska, and implications for volcanic hazards assessment

USGS Publications Warehouse

Waythomas, C.F.; Walder, J.S.; McGimsey, R.G.; Neal, C.A.

1996-01-01

Aniakchak caldera, located on the Alaska Peninsula of southwest Alaska, formerly contained a large lake (estimated volume 3.7 ?? 109 m3) that rapidly drained as a result of failure of the caldera rim sometime after ca. 3400 yr B.P. The peak discharge of the resulting flood was estimated using three methods: (1) flow-competence equations, (2) step-backwater modeling, and (3) a dam-break model. The results of the dam-break model indicate that the peak discharge at the breach in the caldera rim was at least 7.7 ?? 104 m3 s-1, and the maximum possible discharge was ???1.1 ?? 106 m3 s-1. Flow-competence estimates of discharge, based on the largest boulders transported by the flood, indicate that the peak discharge values, which were a few kilometers downstream of the breach, ranged from 6.4 ?? 105 to 4.8 ?? 106 m3 s-1. Similar but less variable results were obtained by step-backwater modeling. Finally, discharge estimates based on regression equations relating peak discharge to the volume and depth of the impounded water, although limited by constraining assumptions, provide results within the range of values determined by the other methods. The discovery and documentation of a flood, caused by the failure of the caldera rim at Aniakchak caldera, underscore the significance and associated hydrologic hazards of potential large floods at other lake-filled calderas.

Estimating individual glomerular volume in the human kidney: clinical perspectives.

PubMed

Puelles, Victor G; Zimanyi, Monika A; Samuel, Terence; Hughson, Michael D; Douglas-Denton, Rebecca N; Bertram, John F; Armitage, James A

2012-05-01

Measurement of individual glomerular volumes (IGV) has allowed the identification of drivers of glomerular hypertrophy in subjects without overt renal pathology. This study aims to highlight the relevance of IGV measurements with possible clinical implications and determine how many profiles must be measured in order to achieve stable size distribution estimates. We re-analysed 2250 IGV estimates obtained using the disector/Cavalieri method in 41 African and 34 Caucasian Americans. Pooled IGV analysis of mean and variance was conducted. Monte-Carlo (Jackknife) simulations determined the effect of the number of sampled glomeruli on mean IGV. Lin's concordance coefficient (R(C)), coefficient of variation (CV) and coefficient of error (CE) measured reliability. IGV mean and variance increased with overweight and hypertensive status. Superficial glomeruli were significantly smaller than juxtamedullary glomeruli in all subjects (P < 0.01), by race (P < 0.05) and in obese individuals (P < 0.01). Subjects with multiple chronic kidney disease (CKD) comorbidities showed significant increases in IGV mean and variability. Overall, mean IGV was particularly reliable with nine or more sampled glomeruli (R(C) > 0.95, <5% difference in CV and CE). These observations were not affected by a reduced sample size and did not disrupt the inverse linear correlation between mean IGV and estimated total glomerular number. Multiple comorbidities for CKD are associated with increased IGV mean and variance within subjects, including overweight, obesity and hypertension. Zonal selection and the number of sampled glomeruli do not represent drawbacks for future longitudinal biopsy-based studies of glomerular size and distribution.

Using GIS to Estimate Lake Volume from Limited Data

EPA Science Inventory

Estimates of lake volume are necessary for estimating residence time or modeling pollutants. Modern GIS methods for calculating lake volume improve upon more dated technologies (e.g. planimeters) and do not require potentially inaccurate assumptions (e.g. volume of a frustum of ...

Supine posture changes lung volumes and increases ventilation heterogeneity in cystic fibrosis.

PubMed

Smith, Laurie J; Macleod, Kenneth A; Collier, Guilhem J; Horn, Felix C; Sheridan, Helen; Aldag, Ina; Taylor, Chris J; Cunningham, Steve; Wild, Jim M; Horsley, Alex

2017-01-01

Lung Clearance Index (LCI) is recognised as an early marker of cystic fibrosis (CF) lung disease. The effect of posture on LCI however is important when considering longitudinal measurements from infancy and when comparing LCI to imaging studies. 35 children with CF and 28 healthy controls (HC) were assessed. Multiple breath washout (MBW) was performed both sitting and supine in triplicate and analysed for LCI, Scond, Sacin, and lung volumes. These values were also corrected for the Fowler dead-space to create 'alveolar' indices. From sitting to supine there was a significant increase in LCI and a significant decrease in FRC for both CF and HC (p<0.01). LCI, when adjusted to estimate 'alveolar' LCI (LCIalv), increased the magnitude of change with posture for both LCIalv and FRCalv in both groups, with a greater effect of change in lung volume in HC compared with children with CF. The % change in LCIalv for all subjects correlated significantly with lung volume % changes, most notably tidal volume/functional residual capacity (Vtalv/FRCalv (r = 0.54,p<0.001)). There is a significant increase in LCI from sitting to supine, which we believe to be in part due to changes in lung volume and also increasing ventilation heterogeneity related to posture. This may have implications in longitudinal measurements from infancy to older childhood and for studies comparing supine imaging methods to LCI.

Photogrammetry and Laser Imagery Tests for Tank Waste Volume Estimates: Summary Report

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

Field, Jim G.

2013-03-27

Feasibility tests were conducted using photogrammetry and laser technologies to estimate the volume of waste in a tank. These technologies were compared with video Camera/CAD Modeling System (CCMS) estimates; the current method used for post-retrieval waste volume estimates. This report summarizes test results and presents recommendations for further development and deployment of technologies to provide more accurate and faster waste volume estimates in support of tank retrieval and closure.

A Comparison of Height-Accumulation and Volume-Equation Methods for Estimating Tree and Stand Volumes

Treesearch

R.B. Ferguson; V. Clark Baldwin

1995-01-01

Estimating tree and stand volume in mature plantations is time consuming, involving much manpower and equipment; however, several sampling and volume-prediction techniques are available. This study showed that a well-constructed, volume-equation method yields estimates comparable to those of the often more time-consuming, height-accumulation method, even though the...

Preoperative TRAM free flap volume estimation for breast reconstruction in lean patients.

PubMed

Minn, Kyung Won; Hong, Ki Yong; Lee, Sang Woo

2010-04-01

To obtain pleasing symmetry in breast reconstruction with transverse rectus abdominis myocutaneous (TRAM) free flap, a large amount of abdominal flap is elevated and remnant tissue is trimmed in most cases. However, elevation of abundant abdominal flap can cause excessive tension in donor site closure and increase the possibility of hypertrophic scarring especially in lean patients. The TRAM flap was divided into 4 zones in routine manner; the depth and dimension of the 4 zones were obtained using ultrasound and AutoCAD (Autodesk Inc., San Rafael, CA), respectively. The acquired numbers were then multiplied to obtain an estimate of volume of each zone and the each zone volume was added. To confirm the relation between the estimated volume and the actual volume, authors compared intraoperative actual TRAM flap volumes with preoperative estimated volumes in 30 consecutive TRAM free flap breast reconstructions. The estimated volumes and the actual elevated volumes of flap were found to be correlated by regression analysis (r = 0.9258, P < 0.01). According to this result, we could confirm the reliability of the preoperative volume estimation using our method. Afterward, the authors applied this method to 7 lean patients by estimation and revision of the design and obtained symmetric results with minimal donor site morbidity. Preoperative estimation of TRAM flap volume with ultrasound and AutoCAD (Autodesk Inc.) allow the authors to attain the precise volume desired for elevation. This method provides advantages in terms of minimal flap trimming, easier closure of donor sites, reduced scar widening and symmetry, especially in lean patients.

Estimates of the volume of water in five coal aquifers, Northern Cheyenne Indian Reservation, southeastern Montana

USGS Publications Warehouse

Tuck, L.K.; Pearson, Daniel K.; Cannon, M.R.; Dutton, DeAnn M.

2013-01-01

The Tongue River Member of the Tertiary Fort Union Formation is the primary source of groundwater in the Northern Cheyenne Indian Reservation in southeastern Montana. Coal beds within this formation generally contain the most laterally extensive aquifers in much of the reservation. The U.S. Geological Survey, in cooperation with the Northern Cheyenne Tribe, conducted a study to estimate the volume of water in five coal aquifers. This report presents estimates of the volume of water in five coal aquifers in the eastern and southern parts of the Northern Cheyenne Indian Reservation: the Canyon, Wall, Pawnee, Knobloch, and Flowers-Goodale coal beds in the Tongue River Member of the Tertiary Fort Union Formation. Only conservative estimates of the volume of water in these coal aquifers are presented. The volume of water in the Canyon coal was estimated to range from about 10,400 acre-feet (75 percent saturated) to 3,450 acre-feet (25 percent saturated). The volume of water in the Wall coal was estimated to range from about 14,200 acre-feet (100 percent saturated) to 3,560 acre-feet (25 percent saturated). The volume of water in the Pawnee coal was estimated to range from about 9,440 acre-feet (100 percent saturated) to 2,360 acre-feet (25 percent saturated). The volume of water in the Knobloch coal was estimated to range from about 38,700 acre-feet (100 percent saturated) to 9,680 acre-feet (25 percent saturated). The volume of water in the Flowers-Goodale coal was estimated to be about 35,800 acre-feet (100 percent saturated). Sufficient data are needed to accurately characterize coal-bed horizontal and vertical variability, which is highly complex both locally and regionally. Where data points are widely spaced, the reliability of estimates of the volume of coal beds is decreased. Additionally, reliable estimates of the volume of water in coal aquifers depend heavily on data about water levels and data about coal-aquifer characteristics. Because the data needed to define the volume of water were sparse, only conservative estimates of the volume of water in the five coal aquifers are presented in this report. These estimates need to be used with caution and mindfulness of the uncertainty associated with them.

Surgeon volume for percutaneous nephrolithotomy is associated with medical costs and length of hospital stay: a nationwide population-based study in Taiwan.

PubMed

Huang, Wei-Yi; Wu, Shiao-Chi; Chen, Yu-Fen; Lan, Chung-Fu; Hsieh, Ju-Ton; Huang, Kuo-How

2014-08-01

To investigate the factors associated with outcomes and medical costs for percutaneous nephrolithotomy (PCNL). The present study uses a subset of the National Health Insurance Research Database (NHIRD), known as the Longitudinal Health Insurance Database 2005 (LHID 2005), which contains the data of all medical benefit claims from 1997 to 2010 for a subset of 1 million enrollees randomly drawn from the population of 22.72 million persons who were enrolled in 2005. The claims data for all subjects with a diagnosis of urolithiasis who underwent PCNL were analyzed. Hospital and surgeon case volume were classified by quartile. The correlations of all patient, surgeon, and hospital variables with the outcomes and medical costs of PCNL were analyzed by generalized estimating equations. A total of 995 subjects received PCNL. In univariate analysis, PCNL performed by high-volume surgeons (≥12) cost 26% less ($2684 vs $1986) and resulted in a 34.3% shorter hospital stay (6.5 vs 9.9 days) compared with low-volume surgeons (≤3). In multivariate analysis, surgeon volume was a significant predictor for medical cost, length of stay, and intensive care unit transfer but not complications and mortality. Surgeon volume was associated with lower medical costs and shorter length of stay after PCNL. Surgeon volume, however, was not an independent predictor of complications and mortality. Our findings have important implications for urologists and policymakers with regard to the cost and effectiveness of PCNL.

Estimation of feline renal volume using computed tomography and ultrasound.

PubMed

Tyson, Reid; Logsdon, Stacy A; Werre, Stephen R; Daniel, Gregory B

2013-01-01

Renal volume estimation is an important parameter for clinical evaluation of kidneys and research applications. A time efficient, repeatable, and accurate method for volume estimation is required. The purpose of this study was to describe the accuracy of ultrasound and computed tomography (CT) for estimating feline renal volume. Standardized ultrasound and CT scans were acquired for kidneys of 12 cadaver cats, in situ. Ultrasound and CT multiplanar reconstructions were used to record renal length measurements that were then used to calculate volume using the prolate ellipsoid formula for volume estimation. In addition, CT studies were reconstructed at 1 mm, 5 mm, and 1 cm, and transferred to a workstation where the renal volume was calculated using the voxel count method (hand drawn regions of interest). The reference standard kidney volume was then determined ex vivo using water displacement with the Archimedes' principle. Ultrasound measurement of renal length accounted for approximately 87% of the variability in renal volume for the study population. The prolate ellipsoid formula exhibited proportional bias and underestimated renal volume by a median of 18.9%. Computed tomography volume estimates using the voxel count method with hand-traced regions of interest provided the most accurate results, with increasing accuracy for smaller voxel sizes in grossly normal kidneys (-10.1 to 0.6%). Findings from this study supported the use of CT and the voxel count method for estimating feline renal volume in future clinical and research studies. © 2012 Veterinary Radiology & Ultrasound.

An assessment of the impact of FIA's default assumptions on the estimates of coarse woody debris volume and biomass

Treesearch

Vicente J. Monleon

2009-01-01

Currently, Forest Inventory and Analysis estimation procedures use Smalian's formula to compute coarse woody debris (CWD) volume and assume that logs lie horizontally on the ground. In this paper, the impact of those assumptions on volume and biomass estimates is assessed using 7 years of Oregon's Phase 2 data. Estimates of log volume computed using Smalian...

Journal of Air Transportation, Volume 8, No. 2. Volume 8, No. 2

NASA Technical Reports Server (NTRS)

Bowen, Brent (Editor); Kabashkin, Igor (Editor); Nickerson, Jocelyn (Editor)

2003-01-01

The mission of the Journal of Air Transportation (JAT) is to provide the global community immediate key resource information in all areas of air transportation. This journal contains articles on the following:Fuel Consumption Modeling of a Transport Category Aircraft: A FlightOperationsQualityAssurance (F0QA) Analysis;Demand for Air Travel in the United States: Bottom-Up Econometric Estimation and Implications for Forecasts by Origin and Destination Pairs;Blind Flying on the Beam: Aeronautical Communication, Navigation and Surveillance: Its Origins and the Politics of Technology: Part I1 Political Oversight and Promotion;Blind Flying on the Beam: Aeronautical Communication, Navigation and Surveillance: Its Origins and the Politics of Technology: Part 111: Emerging Technologies;Ethics Education in University Aviation Management Programs in the US: Part Two B-Statistical Analysis of Current Practice;Integrating Human Factors into the Human-computer Interface: and How Best to Display Meteorological Information for Critical Aviation Decision-making and Performance.

New model for estimating the relationship between surface area and volume in the human body using skeletal remains.

PubMed

Kasabova, Boryana E; Holliday, Trenton W

2015-04-01

A new model for estimating human body surface area and body volume/mass from standard skeletal metrics is presented. This model is then tested against both 1) "independently estimated" body surface areas and "independently estimated" body volume/mass (both derived from anthropometric data) and 2) the cylindrical model of Ruff. The model is found to be more accurate in estimating both body surface area and body volume/mass than the cylindrical model, but it is more accurate in estimating body surface area than it is for estimating body volume/mass (as reflected by the standard error of the estimate when "independently estimated" surface area or volume/mass is regressed on estimates derived from the present model). Two practical applications of the model are tested. In the first test, the relative contribution of the limbs versus the trunk to the body's volume and surface area is compared between "heat-adapted" and "cold-adapted" populations. As expected, the "cold-adapted" group has significantly more of its body surface area and volume in its trunk than does the "heat-adapted" group. In the second test, we evaluate the effect of variation in bi-iliac breadth, elongated or foreshortened limbs, and differences in crural index on the body's surface area to volume ratio (SA:V). Results indicate that the effects of bi-iliac breadth on SA:V are substantial, while those of limb lengths and (especially) the crural index are minor, which suggests that factors other than surface area relative to volume are driving morphological variation and ecogeographical patterning in limb prorportions. © 2014 Wiley Periodicals, Inc.

Formation of South Pole-Aitken Basin as the Result of an Oblique Impact: Implications for Melt Volume and Source of Exposed Materials

NASA Technical Reports Server (NTRS)

Petro, N. E.

2012-01-01

The South Pole-Aitken Basin (SPA) is the largest, deepest, and oldest identified basin on the Moon and contains surfaces that are unique due to their age, composition, and depth of origin in the lunar crust [1-3] (Figure 1). SPA has been a target of interest as an area for robotic sample return in order to determine the age of the basin and the composition and origin of its interior [3-6]. As part of the investigation into the origin of SPA materials there have been several efforts to estimate the likely provenance of regolith material in central SPA [5, 6]. These model estimates suggest that, despite the formation of basins and craters following SPA, the regolith within SPA is dominated by locally derived material. An assumption inherent in these models has been that the locally derived material is primarily SPA impact-melt as opposed to local basement material (e.g. unmelted lower crust). However, the definitive identification of SPA derived impact melt on the basin floor, either by remote sensing [2, 7] or via photogeology [8] is extremely difficult due to the number of subsequent impacts and volcanic activity [3, 4]. In order to identify where SPA produced impact melt may be located, it is important to constrain both how much melt would have been produced in a basin forming impact and the likely source of such melted material. Models of crater and basin formation [9, 10] present clear rationale for estimating the possible volumes and sources of impact melt produced during SPA formation. However, if SPA formed as the result of an oblique impact [11, 12], the volume and depth of origin of melted material could be distinct from similar material in a vertical impact [13].

Improved estimates of partial volume coefficients from noisy brain MRI using spatial context.

PubMed

Manjón, José V; Tohka, Jussi; Robles, Montserrat

2010-11-01

This paper addresses the problem of accurate voxel-level estimation of tissue proportions in the human brain magnetic resonance imaging (MRI). Due to the finite resolution of acquisition systems, MRI voxels can contain contributions from more than a single tissue type. The voxel-level estimation of this fractional content is known as partial volume coefficient estimation. In the present work, two new methods to calculate the partial volume coefficients under noisy conditions are introduced and compared with current similar methods. Concretely, a novel Markov Random Field model allowing sharp transitions between partial volume coefficients of neighbouring voxels and an advanced non-local means filtering technique are proposed to reduce the errors due to random noise in the partial volume coefficient estimation. In addition, a comparison was made to find out how the different methodologies affect the measurement of the brain tissue type volumes. Based on the obtained results, the main conclusions are that (1) both Markov Random Field modelling and non-local means filtering improved the partial volume coefficient estimation results, and (2) non-local means filtering was the better of the two strategies for partial volume coefficient estimation. Copyright 2010 Elsevier Inc. All rights reserved.

The validity of ultrasound estimation of muscle volumes.

PubMed

Infantolino, Benjamin W; Gales, Daniel J; Winter, Samantha L; Challis, John H

2007-08-01

The purpose of this study was to validate ultrasound muscle volume estimation in vivo. To examine validity, vastus lateralis ultrasound images were collected from cadavers before muscle dissection; after dissection, the volumes were determined by hydrostatic weighing. Seven thighs from cadaver specimens were scanned using a 7.5-MHz ultrasound probe (SSD-1000, Aloka, Japan). The perimeter of the vastus lateralis was identified in the ultrasound images and manually digitized. Volumes were then estimated using the Cavalieri principle, by measuring the image areas of sets of parallel two-dimensional slices through the muscles. The muscles were then dissected from the cadavers, and muscle volume was determined via hydrostatic weighing. There was no statistically significant difference between the ultrasound estimation of muscle volume and that estimated using hydrostatic weighing (p > 0.05). The mean percentage error between the two volume estimates was 0.4% +/- 6.9. Three operators all performed four digitizations of all images from one randomly selected muscle; there was no statistical difference between operators or trials and the intraclass correlation was high (>0.8). The results of this study indicate that ultrasound is an accurate method for estimating muscle volumes in vivo.

Preliminary Evidence for the Impact of Combat Experiences on Gray Matter Volume of the Posterior Insula

PubMed Central

Clausen, Ashley N.; Billinger, Sandra A.; Sisante, Jason-Flor V.; Suzuki, Hideo; Aupperle, Robin L.

2017-01-01

Background: Combat-exposed veteran populations are at an increased risk for developing cardiovascular disease. The anterior cingulate cortex (ACC) and insula have been implicated in both autonomic arousal to emotional stressors and homeostatic processes, which may contribute to cardiovascular dysfunction in combat veteran populations. The aim of the present study was to explore the intersecting relationships of combat experiences, rostral ACC and posterior insula volume, and cardiovascular health in a sample of combat veterans. Method: Twenty-four male combat veterans completed clinical assessment of combat experiences and posttraumatic stress symptoms. Subjects completed a magnetic resonance imaging scan and autosegmentation using FreeSurfer was used to estimate regional gray matter volume (controlling for total gray matter volume) of the rostral ACC and posterior insula. Flow-mediated dilation (FMD) was conducted to assess cardiovascular health. Theil-sen robust regressions and Welch's analysis of variance were used to examine relationships of combat experiences and PTSD symptomology with (1) FMD and (2) regional gray matter volume. Results: Increased combat experiences, deployment duration, and multiple deployments were related to smaller posterior insula volume. Combat experiences were marginally associated with poorer cardiovascular health. However, cardiovascular health was not related to rostral ACC or posterior insula volume. Conclusion: The present study provides initial evidence for the relationships of combat experiences, deployment duration, and multiple deployments with smaller posterior insula volume. Results may suggest that veterans with increased combat experiences may exhibit more dysfunction regulating the autonomic nervous system, a key function of the posterior insula. However, the relationship between combat and cardiovascular health was not mediated by regional brain volume. Future research is warranted to further clarify the cardiovascular or functional impact of smaller posterior insula volume in combat veterans. PMID:29312038

Origin and recharge rates of alluvial ground waters, Eastern Desert, Egypt.

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

Sultan, M.; Gheith, H.; Sturchio, N. C.

2002-04-12

Stable isotope and tritium analyses of shallow ground waters in the Eastern Desert of Egypt showed that the waters were derived largely by evaporation of regional precipitation and at least partly from precipitation in the past 45 y. To estimate the ground water recharge rate, we developed an integrated hydrologic model based on satellite data, geologic maps, infiltration parameters, and spatial rainfall distribution. Modeling indicated that during a severe 1994 storm, recharge through transmission loss in Wadi El-Tarfa was 21% of the precipitation volume. From archival precipitation data, we estimate that the annual recharge rate for the El-Tarfa alluvial aquifermore » is 4.7 x 10{sup 6} m{sup 3}. Implications for the use of renewable ground waters in arid areas of Egypt and in neighboring countries are clear.« less

Correlation of ultrasound estimated placental volume and umbilical cord blood volume in term pregnancy.

PubMed

Pannopnut, Papinwit; Kitporntheranunt, Maethaphan; Paritakul, Panwara; Kongsomboon, Kittipong

2015-01-01

To investigate the correlation between ultrasound measured placental volume and collected umbilical cord blood (UCB) volume in term pregnancy. An observational cross-sectional study of term singleton pregnant women in the labor ward at Maha Chakri Sirindhorn Medical Center was conducted. Placental thickness, height, and width were measured using two-dimensional (2D) ultrasound and calculated for placental volume using the volumetric mathematic model. After the delivery of the baby, UCB was collected and measured for its volume immediately. Then, birth weight, placental weight, and the actual placental volume were analyzed. The Pearson's correlation was used to determine the correlation between each two variables. A total of 35 pregnant women were eligible for the study. The mean and standard deviation of estimated placental volume and actual placental volume were 534±180 mL and 575±118 mL, respectively. The median UCB volume was 140 mL (range 98-220 mL). The UCB volume did not have a statistically significant correlation with the estimated placental volume (correlation coefficient 0.15; p=0.37). However, the UCB volume was significantly correlated with the actual placental volume (correlation coefficient 0.62; p<0.001) and birth weight (correlation coefficient 0.38; p=0.02). The estimated placental volume by 2D ultrasound was not significantly correlated with the UCB volume. Further studies to establish the correlation between the UCB volume and the estimated placental volume using other types of placental imaging may be needed.

Quantitative CT: technique dependence of volume estimation on pulmonary nodules

NASA Astrophysics Data System (ADS)

Chen, Baiyu; Barnhart, Huiman; Richard, Samuel; Colsher, James; Amurao, Maxwell; Samei, Ehsan

2012-03-01

Current estimation of lung nodule size typically relies on uni- or bi-dimensional techniques. While new three-dimensional volume estimation techniques using MDCT have improved size estimation of nodules with irregular shapes, the effect of acquisition and reconstruction parameters on accuracy (bias) and precision (variance) of the new techniques has not been fully investigated. To characterize the volume estimation performance dependence on these parameters, an anthropomorphic chest phantom containing synthetic nodules was scanned and reconstructed with protocols across various acquisition and reconstruction parameters. Nodule volumes were estimated by a clinical lung analysis software package, LungVCAR. Precision and accuracy of the volume assessment were calculated across the nodules and compared between protocols via a generalized estimating equation analysis. Results showed that the precision and accuracy of nodule volume quantifications were dependent on slice thickness, with different dependences for different nodule characteristics. Other parameters including kVp, pitch, and reconstruction kernel had lower impact. Determining these technique dependences enables better volume quantification via protocol optimization and highlights the importance of consistent imaging parameters in sequential examinations.

Estimating sugar maple bark thickness and volume.

Treesearch

Charles L. Stayton; Michael Hoffman

1970-01-01

Sugar maple bark thickness and volume were estimated using first a published method, then equations developed by the authors. Both methods gave estimates that compared closely with measured values. Information is also presented on variation in bark thickness and on weight and volume of bark as a percentage of total merchantable stem weight and volume.

Implications of variable waste placement conditions for MSW landfills.

PubMed

Cox, Jason T; Yesiller, Nazli; Hanson, James L

2015-12-01

This investigation was conducted to evaluate the influence of waste placement practices on the engineering response of municipal solid waste (MSW) landfills. Waste placement conditions were varied by moisture addition to the wastes at the time of disposal. Tests were conducted at a California landfill in test plots (residential component of incoming wastes) and full-scale active face (all incoming wastes including residential, commercial, and self-delivered components). The short-term effects of moisture addition were assessed by investigating compaction characteristics and moisture distribution and the long-term effects by estimating settlement characteristics of the variably placed wastes. In addition, effects on engineering properties including hydraulic conductivity and shear strength, as well as economic aspects were investigated. The unit weight of the wastes increased with moisture addition to a maximum value and then decreased with further moisture addition. At the optimum moisture conditions, 68% more waste could be placed in the same landfill volume compared to the baseline conditions. Moisture addition raised the volumetric moisture content of the wastes to the range 33-42%, consistent with values at and above field capacity. Moisture transfer occurred between consecutive layers of compacted wastes and a moisture addition schedule of 2 days of as-received conditions and 1 day of moisture addition was recommended. Settlement of wastes was estimated to increase with moisture addition, with a 34% increase at optimum moisture compared to as-received conditions. Overall, moisture addition during compaction increased unit weight, the amount of incoming wastes disposed in a given landfill volume, biological activity potential, and predicted settlement. The combined effects have significant environmental and economic implications for landfill operations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison of volume estimation methods for pancreatic islet cells

NASA Astrophysics Data System (ADS)

Dvořák, JiřÃ.­; Å vihlík, Jan; Habart, David; Kybic, Jan

2016-03-01

In this contribution we study different methods of automatic volume estimation for pancreatic islets which can be used in the quality control step prior to the islet transplantation. The total islet volume is an important criterion in the quality control. Also, the individual islet volume distribution is interesting -- it has been indicated that smaller islets can be more effective. A 2D image of a microscopy slice containing the islets is acquired. The input of the volume estimation methods are segmented images of individual islets. The segmentation step is not discussed here. We consider simple methods of volume estimation assuming that the islets have spherical or ellipsoidal shape. We also consider a local stereological method, namely the nucleator. The nucleator does not rely on any shape assumptions and provides unbiased estimates if isotropic sections through the islets are observed. We present a simulation study comparing the performance of the volume estimation methods in different scenarios and an experimental study comparing the methods on a real dataset.

External validation of a forest inventory and analysis volume equation and comparisons with estimates from multiple stem-profile models

Treesearch

Christopher M. Oswalt; Adam M. Saunders

2009-01-01

Sound estimation procedures are desideratum for generating credible population estimates to evaluate the status and trends in resource conditions. As such, volume estimation is an integral component of the U.S. Department of Agriculture, Forest Service, Forest Inventory and Analysis (FIA) program's reporting. In effect, reliable volume estimation procedures are...

True Volumes of Slope Failure Estimated From a Quaternary Mass-Transport Deposit in the Northern South China Sea

NASA Astrophysics Data System (ADS)

Sun, Qiliang; Alves, Tiago M.; Lu, Xiangyang; Chen, Chuanxu; Xie, Xinong

2018-03-01

Submarine slope failure can mobilize large amounts of seafloor sediment, as shown in varied offshore locations around the world. Submarine landslide volumes are usually estimated by mapping their tops and bases on seismic data. However, two essential components of the total volume of failed sediments are overlooked in most estimates: (a) the volume of subseismic turbidites generated during slope failure and (b) the volume of shear compaction occurring during the emplacement of failed sediment. In this study, the true volume of a large submarine landslide in the northern South China Sea is estimated using seismic, multibeam bathymetry and Ocean Drilling Program/Integrated Ocean Drilling Program well data. The submarine landslide was evacuated on the continental slope and deposited in an ocean basin connected to the slope through a narrow moat. This particular character of the sea floor provides an opportunity to estimate the amount of strata remobilized by slope instability. The imaged volume of the studied landslide is 1035 ± 64 km3, 406 ± 28 km3 on the slope and 629 ± 36 km3 in the ocean basin. The volume of subseismic turbidites is 86 km3 (median value), and the volume of shear compaction is 100 km3, which are 8.6% and 9.7% of the landslide volume imaged on seismic data, respectively. This study highlights that the original volume of the failed sediments is significantly larger than that estimated using seismic and bathymetric data. Volume loss related to the generation of landslide-related turbidites and shear compaction must be considered when estimating the total volume of failed strata in the submarine realm.

Noninvasive evaluation of left ventricular elastance according to pressure-volume curves modeling in arterial hypertension.

PubMed

Bonnet, Benjamin; Jourdan, Franck; du Cailar, Guilhem; Fesler, Pierre

2017-08-01

End-systolic left ventricular (LV) elastance ( E es ) has been previously calculated and validated invasively using LV pressure-volume (P-V) loops. Noninvasive methods have been proposed, but clinical application remains complex. The aims of the present study were to 1 ) estimate E es according to modeling of the LV P-V curve during ejection ("ejection P-V curve" method) and validate our method with existing published LV P-V loop data and 2 ) test the clinical applicability of noninvasively detecting a difference in E es between normotensive and hypertensive subjects. On the basis of the ejection P-V curve and a linear relationship between elastance and time during ejection, we used a nonlinear least-squares method to fit the pressure waveform. We then computed the slope and intercept of time-varying elastance as well as the volume intercept (V 0 ). As a validation, 22 P-V loops obtained from previous invasive studies were digitized and analyzed using the ejection P-V curve method. To test clinical applicability, ejection P-V curves were obtained from 33 hypertensive subjects and 32 normotensive subjects with carotid tonometry and real-time three-dimensional echocardiography during the same procedure. A good univariate relationship ( r 2  = 0.92, P < 0.005) and good limits of agreement were found between the invasive calculation of E es and our new proposed ejection P-V curve method. In hypertensive patients, an increase in arterial elastance ( E a ) was compensated by a parallel increase in E es without change in E a / E es In addition, the clinical reproducibility of our method was similar to that of another noninvasive method. In conclusion, E es and V 0 can be estimated noninvasively from modeling of the P-V curve during ejection. This approach was found to be reproducible and sensitive enough to detect an expected increase in LV contractility in hypertensive patients. Because of its noninvasive nature, this methodology may have clinical implications in various disease states. NEW & NOTEWORTHY The use of real-time three-dimensional echocardiography-derived left ventricular volumes in conjunction with carotid tonometry was found to be reproducible and sensitive enough to detect expected differences in left ventricular elastance in arterial hypertension. Because of its noninvasive nature, this methodology may have clinical implications in various disease states. Copyright © 2017 the American Physiological Society.

Individual differences in GABA content are reliable but are not uniform across the human cortex

PubMed Central

Greenhouse, Ian; Noah, Sean; Maddock, Richard J; Ivry, Richard B

2016-01-01

1H magnetic resonance spectroscopy (MRS) provides a powerful tool to measure gamma-aminobutyric acid (GABA), the principle inhibitory neurotransmitter in the human brain. We asked whether individual differences in MRS estimates of GABA are uniform across the cortex or vary between regions. In two sessions, resting GABA concentrations in the lateral prefrontal, sensorimotor, dorsal premotor, and occipital cortices were measured in twenty-eight healthy individuals. GABA estimates within each region were stable across weeks, with low coefficients of variation. Despite this stability, the GABA estimates were not correlated between regions. In contrast, the percentage of brain tissue per volume, a control measure, was correlated between the three anterior regions. These results provide an interesting dissociation between an anatomical measure of individual differences and a neurochemical measure. The different patterns of anatomy and GABA concentrations have implications for understanding regional variation in the molecular topography of the brain in health and disease. PMID:27288552

Exsanguinated blood volume estimation using fractal analysis of digital images.

PubMed

Sant, Sonia P; Fairgrieve, Scott I

2012-05-01

The estimation of bloodstain volume using fractal analysis of digital images of passive blood stains is presented. Binary digital photos of bloodstains of known volumes (ranging from 1 to 7 mL), dispersed in a defined area, were subjected to image analysis using FracLac V. 2.0 for ImageJ. The box-counting method was used to generate a fractal dimension for each trial. A positive correlation between the generated fractal number and the volume of blood was found (R(2) = 0.99). Regression equations were produced to estimate the volume of blood in blind trials. An error rate ranging from 78% for 1 mL to 7% for 6 mL demonstrated that as the volume increases so does the accuracy of the volume estimation. This method used in the preliminary study proved that bloodstain patterns may be deconstructed into mathematical parameters, thus removing the subjective element inherent in other methods of volume estimation. © 2012 American Academy of Forensic Sciences.

Human Cardiovascular Adaptation to Weightlessness

NASA Technical Reports Server (NTRS)

Norsk, Peter

2011-01-01

Entering weightlessness (0 G) induces immediately a shift of blood and fluid from the lower to the upper parts of the body inducing expansion of the cardiac chambers (Bungo et al. 1986; Charles & Lathers 1991; Videbaek & Norsk 1997). For many years the effects of sudden 0 G on central venous pressure (CVP) was discussed, and it puzzled researchers that CVP compared to the 1-G supine position decreased during the initial hours of spaceflight, when at the same time left atrial diameter increased (Buckey et al. 1996). By measuring esophageal pressure as an estimate of inter-pleural pressure, it was later shown that this pressure decreases more than CVP does during 0 G induced by parabolic flights (Videbaek & Norsk 1997). Thus, transmural CVP is increased, which distends the cardiac chambers. This unique lung-heart interaction whereby 1) inter-pleural pressure decreases and 2) central blood volume is expanded is unique for 0 G. Because transmural CVP is increased, stroke volume increases according to the law of Frank-Starling leading to an increase in cardiac output, which is maintained increased during months of 0 G in space to levels of some 25% above that of the 1-G seated position (Norsk unpublished). Simultaneously, sympathetic nervous activity is at the level of the upright 1-G posture, which is difficult to explain based on the high stroke volume and decreased blood pressure and systemic vascular resistance. This paradox should be explored and the mechanisms revealed, because it might have implications for estimating the cardiovascular risk of travelling in space.

Perennial snow and ice volumes on Iliamna Volcano, Alaska, estimated with ice radar and volume modeling

USGS Publications Warehouse

Trabant, Dennis C.

1999-01-01

The volume of four of the largest glaciers on Iliamna Volcano was estimated using the volume model developed for evaluating glacier volumes on Redoubt Volcano. The volume model is controlled by simulated valley cross sections that are constructed by fitting third-order polynomials to the shape of the valley walls exposed above the glacier surface. Critical cross sections were field checked by sounding with ice-penetrating radar during July 1998. The estimated volumes of perennial snow and glacier ice for Tuxedni, Lateral, Red, and Umbrella Glaciers are 8.6, 0.85, 4.7, and 0.60 cubic kilometers respectively. The estimated volume of snow and ice on the upper 1,000 meters of the volcano is about 1 cubic kilometer. The volume estimates are thought to have errors of no more than ?25 percent. The volumes estimated for the four largest glaciers are more than three times the total volume of snow and ice on Mount Rainier and about 82 times the total volume of snow and ice that was on Mount St. Helens before its May 18, 1980 eruption. Volcanoes mantled by substantial snow and ice covers have produced the largest and most catastrophic lahars and floods. Therefore, it is prudent to expect that, during an eruptive episode, flooding and lahars threaten all of the drainages heading on Iliamna Volcano. On the other hand, debris avalanches can happen any time. Fortunately, their influence is generally limited to the area within a few kilometers of the summit.

Glacier volume estimation of Cascade Volcanoes—an analysis and comparison with other methods

USGS Publications Warehouse

Driedger, Carolyn L.; Kennard, P.M.

1986-01-01

During the 1980 eruption of Mount St. Helens, the occurrence of floods and mudflows made apparent a need to assess mudflow hazards on other Cascade volcanoes. A basic requirement for such analysis is information about the volume and distribution of snow and ice on these volcanoes. An analysis was made of the volume-estimation methods developed by previous authors and a volume estimation method was developed for use in the Cascade Range. A radio echo-sounder, carried in a backpack, was used to make point measurements of ice thickness on major glaciers of four Cascade volcanoes (Mount Rainier, Washington; Mount Hood and the Three Sisters, Oregon; and Mount Shasta, California). These data were used to generate ice-thickness maps and bedrock topographic maps for developing and testing volume-estimation methods. Subsequently, the methods were applied to the unmeasured glaciers on those mountains and, as a test of the geographical extent of applicability, to glaciers beyond the Cascades having measured volumes. Two empirical relationships were required in order to predict volumes for all the glaciers. Generally, for glaciers less than 2.6 km in length, volume was found to be estimated best by using glacier area, raised to a power. For longer glaciers, volume was found to be estimated best by using a power law relationship, including slope and shear stress. The necessary variables can be estimated from topographic maps and aerial photographs.

Seismic source functions from free-field ground motions recorded on SPE: Implications for source models of small, shallow explosions

NASA Astrophysics Data System (ADS)

Rougier, Esteban; Patton, Howard J.

2015-05-01

Reduced displacement potentials (RDPs) for chemical explosions of the Source Physics Experiments (SPE) in granite at the Nevada Nuclear Security Site are estimated from free-field ground motion recordings. Far-field P wave source functions are proportional to the time derivative of RDPs. Frequency domain comparisons between measured source functions and model predictions show that high-frequency amplitudes roll off as ω- 2, but models fail to predict the observed seismic moment, corner frequency, and spectral overshoot. All three features are fit satisfactorily for the SPE-2 test after cavity radius Rc is reduced by 12%, elastic radius is reduced by 58%, and peak-to-static pressure ratio on the elastic radius is increased by 100%, all with respect to the Mueller-Murphy model modified with the Denny-Johnson Rc scaling law. A large discrepancy is found between the cavity volume inferred from RDPs and the volume estimated from laser scans of the emplacement hole. The measurements imply a scaled Rc of ~5 m/kt1/3, more than a factor of 2 smaller than nuclear explosions. Less than 25% of the seismic moment can be attributed to cavity formation. A breakdown of the incompressibility assumption due to shear dilatancy of the source medium around the cavity is the likely explanation. New formulas are developed for volume changes due to medium bulking (or compaction). A 0.04% decrease of average density inside the elastic radius accounts for the missing volumetric moment. Assuming incompressibility, established Rc scaling laws predicted the moment reasonable well, but it was only fortuitous because dilation of the source medium compensated for the small cavity volume.

Validated Alzheimer's Disease Risk Index (ANU-ADRI) is associated with smaller volumes in the default mode network in the early 60s.

PubMed

Cherbuin, Nicolas; Shaw, Marnie E; Walsh, Erin; Sachdev, Perminder; Anstey, Kaarin J

2017-12-14

Strong evidence is available suggesting that effective reduction of exposure to demonstrated modifiable risk factors in mid-life or before could significantly decrease the incidence of Alzheimer's disease (AD) and delay its onset. A key ingredient to achieving this goal is the reliable identification of individuals at risk well before they develop clinical symptoms. The aim of this study was to provide further neuroimaging evidence of the effectiveness of a validated tool, the ANU Alzheimer's Disease Risk Index, for the assessment of future risk of cognitive decline. Participants were 461 (60-64 years, 48% female) community-living individuals free of dementia at baseline. Associations between risk estimates obtained with the ANU-ADRI, total and regional brain volumes including in the default mode network (DMN) measured at the same assessment and diagnosis of MCI/dementia over a 12-year follow-up were tested in a large sample of community-living individuals free of dementia at baseline. Higher risk estimates on the ANU-ADRI were associated with lower cortical gray matter and particularly in the DMN. Importantly, difference in participants with high and low risk scores explained 7-9% of the observed difference in gray matter volume. In this sample, every one additional risk point on the ANU-ADRI was associated with an 8% increased risk of developing MCI/dementia over a 12-year follow-up and this association was partly mediated by a sub-region of the DMN. Risk of cognitive decline assessed with a validated instrument is associated with gray matter volume, particularly in the DMN, a region known to be implicated in the pathological process of the disease.

Connectivity of earthquake-triggered landslides with the fluvial network: Implications for landslide sediment transport after the 2008 Wenchuan earthquake

NASA Astrophysics Data System (ADS)

Li, Gen; West, A. Joshua; Densmore, Alexander L.; Hammond, Douglas E.; Jin, Zhangdong; Zhang, Fei; Wang, Jin; Hilton, Robert G.

2016-04-01

Evaluating the influence of earthquakes on erosion, landscape evolution, and sediment-related hazards requires understanding fluvial transport of material liberated in earthquake-triggered landslides. The location of landslides relative to river channels is expected to play an important role in postearthquake sediment dynamics. In this study, we assess the position of landslides triggered by the Mw 7.9 Wenchuan earthquake, aiming to understand the relationship between landslides and the fluvial network of the steep Longmen Shan mountain range. Combining a landslide inventory map and geomorphic analysis, we quantify landslide-channel connectivity in terms of the number of landslides, landslide area, and landslide volume estimated from scaling relationships. We observe a strong spatial variability in landslide-channel connectivity, with volumetric connectivity (ξ) ranging from ~20% to ~90% for different catchments. This variability is linked to topographic effects that set local channel densities, seismic effects (including seismogenic faulting) that regulate landslide size, and substrate effects that may influence both channelization and landslide size. Altogether, we estimate that the volume of landslides connected to channels comprises 43 + 9/-7% of the total coseismic landslide volume. Following the Wenchuan earthquake, fine-grained (<~0.25 mm) suspended sediment yield across the Longmen Shan catchments is positively correlated to catchment-wide landslide density, but this correlation is statistically indistinguishable whether or not connectivity is considered. The weaker-than-expected influence of connectivity on suspended sediment yield may be related to mobilization of fine-grained landslide material that resides in hillslope domains, i.e., not directly connected to river channels. In contrast, transport of the coarser fraction (which makes up >90% of the total landslide volume) may be more significantly affected by landslide locations.

A model for calculating eruptive volumes for monogenetic volcanoes — Implication for the Quaternary Auckland Volcanic Field, New Zealand

NASA Astrophysics Data System (ADS)

Kereszturi, Gábor; Németh, Károly; Cronin, Shane J.; Agustín-Flores, Javier; Smith, Ian E. M.; Lindsay, Jan

2013-10-01

Monogenetic basaltic volcanism is characterised by a complex array of behaviours in the spatial distribution of magma output and also temporal variability in magma flux and eruptive frequency. Investigating this in detail is hindered by the difficulty in evaluating ages of volcanic events as well as volumes erupted in each volcano. Eruptive volumes are an important input parameter for volcanic hazard assessment and may control eruptive scenarios, especially transitions between explosive and effusive behaviour and the length of eruptions. Erosion, superposition and lack of exposure limit the accuracy of volume determination, even for very young volcanoes. In this study, a systematic volume estimation model is developed and applied to the Auckland Volcanic Field in New Zealand. In this model, a basaltic monogenetic volcano is categorised in six parts. Subsurface portions of volcanoes, such as diatremes beneath phreatomagmatic volcanoes, or crater infills, are approximated by geometrical considerations, based on exposed analogue volcanoes. Positive volcanic landforms, such as scoria/spatter cones, tephras rings and lava flow, were defined by using a Light Detection and Ranging (LiDAR) survey-based Digital Surface Model (DSM). Finally, the distal tephra associated with explosive eruptions was approximated using published relationships that relate original crater size to ejecta volumes. Considering only those parts with high reliability, the overall magma output (converted to Dense Rock Equivalent) for the post-250 ka active Auckland Volcanic Field in New Zealand is a minimum of 1.704 km3. This is made up of 1.329 km3 in lava flows, 0.067 km3 in phreatomagmatic crater lava infills, 0.090 km3 within tephra/tuff rings, 0.112 km3 inside crater lava infills, and 0.104 km3 within scoria cones. Using the minimum eruptive volumes, the spatial and temporal magma fluxes are estimated at 0.005 km3/km2 and 0.007 km3/ka. The temporal-volumetric evolution of Auckland is characterised by an increasing magma flux in the last 40 ky, which is inferred to be triggered by plate tectonics processes (e.g. increased asthenospheric shearing and backarc spreading of underneath the Auckland region).

Genetic Overlap Between Schizophrenia and Volumes of Hippocampus, Putamen, and Intracranial Volume Indicates Shared Molecular Genetic Mechanisms.

PubMed

Smeland, Olav B; Wang, Yunpeng; Frei, Oleksandr; Li, Wen; Hibar, Derrek P; Franke, Barbara; Bettella, Francesco; Witoelar, Aree; Djurovic, Srdjan; Chen, Chi-Hua; Thompson, Paul M; Dale, Anders M; Andreassen, Ole A

2018-06-06

Schizophrenia (SCZ) is associated with differences in subcortical brain volumes and intracranial volume (ICV). However, little is known about the underlying etiology of these brain alterations. Here, we explored whether brain structure volumes and SCZ share genetic risk factors. Using conditional false discovery rate (FDR) analysis, we integrated genome-wide association study (GWAS) data on SCZ (n = 82315) and GWAS data on 7 subcortical brain volumes and ICV (n = 11840). By conditioning the FDR on overlapping associations, this statistical approach increases power to discover genetic loci. To assess the credibility of our approach, we studied the identified loci in larger GWAS samples on ICV (n = 26577) and hippocampal volume (n = 26814). We observed polygenic overlap between SCZ and volumes of hippocampus, putamen, and ICV. Based on conjunctional FDR < 0.05, we identified 2 loci shared between SCZ and ICV implicating genes FOXO3 (rs10457180) and ITIH4 (rs4687658), 2 loci shared between SCZ and hippocampal volume implicating SLC4A10 (rs4664442) and SPATS2L (rs1653290), and 2 loci shared between SCZ and volume of putamen implicating DCC (rs4632195) and DLG2 (rs11233632). The loci shared between SCZ and hippocampal volume or ICV had not reached significance in the primary GWAS on brain phenotypes. Proving our point of increased power, 2 loci did reach genome-wide significance with ICV (rs10457180) and hippocampal volume (rs4664442) in the larger GWAS. Three of the 6 identified loci are novel for SCZ. Altogether, the findings provide new insights into the relationship between SCZ and brain structure volumes, suggesting that their genetic architectures are not independent.

Corpus callosum volumes in the 5 years following the first-episode of schizophrenia: Effects of antipsychotics, chronicity and maturation.

PubMed

de Moura, Mariana T M; Zanetti, Marcus V; Duran, Fabio L S; Schaufelberger, Maristela S; Menezes, Paulo R; Scazufca, Marcia; Busatto, Geraldo F; Serpa, Mauricio H

2018-01-01

White matter (WM) structural changes, particularly affecting the corpus callosum (CC), seem to be critically implicated in psychosis. Whether such abnormalities are progressive or static is still a matter of debate in schizophrenia research. Aberrant maturation processes might also influence the longitudinal trajectory of age-related CC changes in schizophrenia patients. We investigated whether patients with first-episode schizophrenia-related psychoses (FESZ) would present longitudinal CC and whole WM volume changes over the 5 years after disease onset. Thirty-two FESZ patients and 34 controls recruited using a population-based design completed a 5-year assessment protocol, including structural MRI scanning at baseline and follow-up. The linear effects of disease duration, clinical outcome and antipsychotic (AP) use over time on WM and CC volumes were studied using both voxelwise and volume-based morphometry analyses. We also examined maturation/aging abnormalities through cross-sectional analyses of age-related trajectories of total WM and CC volume changes. No interaction between diagnosis and time was observed, and clinical outcome did not influence CC volumes in patients. On the other hand, FESZ patients continuously exposed to AP medication showed volume increase over time in posterior CC. Curve-estimation analyses revealed a different aging pattern in FESZ patients versus controls: while patients displayed a linear decline of total WM and anterior CC volumes with age, a non-linear trajectory of total WM and relative preservation of CC volumes were observed in controls. Continuous AP exposure can influence CC morphology during the first years after schizophrenia onset. Schizophrenia is associated with an abnormal pattern of total WM and anterior CC aging during non-elderly adulthood, and this adds complexity to the discussion on the static or progressive nature of structural abnormalities in psychosis.

Estimating individual glomerular volume in the human kidney: clinical perspectives

PubMed Central

Puelles, Victor G.; Zimanyi, Monika A.; Samuel, Terence; Hughson, Michael D.; Douglas-Denton, Rebecca N.; Bertram, John F.

2012-01-01

Background. Measurement of individual glomerular volumes (IGV) has allowed the identification of drivers of glomerular hypertrophy in subjects without overt renal pathology. This study aims to highlight the relevance of IGV measurements with possible clinical implications and determine how many profiles must be measured in order to achieve stable size distribution estimates. Methods. We re-analysed 2250 IGV estimates obtained using the disector/Cavalieri method in 41 African and 34 Caucasian Americans. Pooled IGV analysis of mean and variance was conducted. Monte-Carlo (Jackknife) simulations determined the effect of the number of sampled glomeruli on mean IGV. Lin’s concordance coefficient (RC), coefficient of variation (CV) and coefficient of error (CE) measured reliability. Results. IGV mean and variance increased with overweight and hypertensive status. Superficial glomeruli were significantly smaller than juxtamedullary glomeruli in all subjects (P < 0.01), by race (P < 0.05) and in obese individuals (P < 0.01). Subjects with multiple chronic kidney disease (CKD) comorbidities showed significant increases in IGV mean and variability. Overall, mean IGV was particularly reliable with nine or more sampled glomeruli (RC > 0.95, <5% difference in CV and CE). These observations were not affected by a reduced sample size and did not disrupt the inverse linear correlation between mean IGV and estimated total glomerular number. Conclusions. Multiple comorbidities for CKD are associated with increased IGV mean and variance within subjects, including overweight, obesity and hypertension. Zonal selection and the number of sampled glomeruli do not represent drawbacks for future longitudinal biopsy-based studies of glomerular size and distribution. PMID:21984554

Effect of Reinforcer Magnitude on Performance Maintained by Progressive-Ratio Schedules

PubMed Central

Rickard, J.F; Body, S; Zhang, Z; Bradshaw, C.M; Szabadi, E

2009-01-01

This experiment examined the relationship between reinforcer magnitude and quantitative measures of performance on progressive-ratio schedules. Fifteen rats were trained under a progressive-ratio schedule in seven phases of the experiment in which the volume of a 0.6-M sucrose solution reinforcer was varied within the range 6–300 µl. Overall response rates in successive ratios conformed to a bitonic equation derived from Killeen's (1994) Mathematical Principles of Reinforcement. The “specific activation” parameter, a, which is presumed to reflect the incentive value of the reinforcer, was a monotonically increasing function of reinforcer volume; the “response time” parameter, δ, which defines the minimum response time, increased as a function of reinforcer volume; the “currency” parameter, β, which is presumed to reflect the coupling of responses to the reinforcer, declined as a function of volume. Running response rate (response rate calculated after exclusion of the postreinforcement pause) decayed monotonically as a function of ratio size; the index of curvature of this function increased as a function of reinforcer volume. Postreinforcement pause increased as a function of ratio size. Estimates of a derived from overall response rates and postreinforcement pauses showed a modest positive correlation across conditions and between animals. Implications of the results for the quantification of reinforcer value and for the use of progressive-ratio schedules in behavioral neuroscience are discussed. PMID:19230513

Effect of reinforcer magnitude on performance maintained by progressive-ratio schedules.

PubMed

Rickard, J F; Body, S; Zhang, Z; Bradshaw, C M; Szabadi, E

2009-01-01

This experiment examined the relationship between reinforcer magnitude and quantitative measures of performance on progressive-ratio schedules. Fifteen rats were trained under a progressive-ratio schedule in seven phases of the experiment in which the volume of a 0.6-M sucrose solution reinforcer was varied within the range 6-300 microl. Overall response rates in successive ratios conformed to a bitonic equation derived from Killeen's (1994) Mathematical Principles of Reinforcement. The "specific activation" parameter, a, which is presumed to reflect the incentive value of the reinforcer, was a monotonically increasing function of reinforcer volume; the "response time" parameter, delta, which defines the minimum response time, increased as a function of reinforcer volume; the "currency" parameter, beta, which is presumed to reflect the coupling of responses to the reinforcer, declined as a function of volume. Running response rate (response rate calculated after exclusion of the postreinforcement pause) decayed monotonically as a function of ratio size; the index of curvature of this function increased as a function of reinforcer volume. Postreinforcement pause increased as a function of ratio size. Estimates of a derived from overall response rates and postreinforcement pauses showed a modest positive correlation across conditions and between animals. Implications of the results for the quantification of reinforcer value and for the use of progressive-ratio schedules in behavioral neuroscience are discussed.

A field test of cut-off importance sampling for bole volume

Treesearch

Jeffrey H. Gove; Harry T. Valentine; Michael J. Holmes

2000-01-01

Cut-off importance sampling has recently been introduced as a technique for estimating bole volume to some point below the tree tip, termed the cut-off point. A field test of this technique was conducted on a small population of eastern white pine trees using dendrometry as the standard for volume estimation. Results showed that the differences in volume estimates...

A New Technique For Quantifying Effusive Volcanic Activity at Tolbachik Volcano Using Multiple Remote Sensing Platforms

NASA Astrophysics Data System (ADS)

McAlpin, D. B.; Meyer, F. J.; Dehn, J.; Webley, P. W.

2016-12-01

In 1976, "The Great Tolbachik Fissure Eruption," became the largest basaltic eruption in the recorded history of the Kamchatka Peninsula. In November 2012, after thirty-six years of quiescence, Tolbachik again erupted, and continued for nine months until its end in August, 2013. Observers of the 2012-13 eruption reported a mostly effusive eruption from two main fissures, long, rapidly moving lava flows, and ash clouds of up to 6 km. Initial estimates of effusive activity reported an approximate volume of 0.52 km³ over an area of more than 35 km². In this analysis, we provide updated effusion estimates for the Tolbachik eruption, determined by thermal data acquired by the Advanced Very High Resolution Radiometer (AVHRR) satellites. Each of the four AVHRR satellites carries a broad-band, five channel sensor that acquires data in the visible and infrared portions of the electromagnetic spectrum, with each satellite completing 14 daily Earth orbits. A critical component to the volume estimates is a determination of fissure size and the area of lava flow at different times during the eruption. For this purpose, we acquired optical satellite images obtained from three orbiting platforms: the Advanced Land Imager (ALI),) aboard the Earth Observer-1 (EO-1) satellite, the Operational Land Imager (OLI) aboard Landsat 8, and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) aboard NASA's Terra satellite. From these multiple platforms, lava flow maps were prepared from repeat acquisitions over the course of the eruption. Periodic lava flow measurements clarify effusion rates as instantaneous discharge rates, mean effusion rates over time, and an overall effusion rate over the entire eruption. Given the natural limitations of effusion estimates derived from thermal data, our results are compared to effusion estimates derived by DEM differencing to evaluate accuracy. This analysis is a true multi-sensor technique that affords a method to rapidly quantify effusive volcanic activity in terms of flow temperature, lava volume, and area on a basis coeval to the eruption, and has important implications for scientific and hazard analyses of future volcanic episodes.

[Interdisciplinary clinical pathway for colorectal cancer].

PubMed

Fischbach, W; Engemann, R

2006-07-01

Limited financial resources in public health care have led to the introduction of clinical pathways as a means to a better effectivity and efficacy. Colorectal cancer met the requirements for establishing such a pathway in a distinguished way: high patient volume, high costs, interdisciplinary multi-modal treatment concepts in a relevant frequency, and existing evidence based guidelines. This article gives an example of a clinical pathway for colorectal cancer as established in our hospital. The potential of such pathways to save costs as well as their implications on treatment results and patients' satisfaction will have to be critically analyzed in the future before their value can be definitely estimated.

A radiographic method to estimate lung volume and its use in small mammals.

PubMed

Canals, Mauricio; Olivares, Ricardo; Rosenmann, Mario

2005-01-01

In this paper we develop a method to estimate lung volume using chest x-rays of small mammals. We applied this method to assess the lung volume of several rodents. We showed that a good estimator of the lung volume is: V*L = 0.496 x VRX approximately equal to 1/2 x VRX, where VRX is a measurement obtained from the x-ray that represents the volume of a rectangular box containing the lungs and mediastinum organs. The proposed formula may be interpreted as the volume of an ellipsoid formed by both lungs joined at their bases. When that relationship was used to estimate lung volume, values similar to those expected from allometric relationship were found in four rodents. In two others, M. musculus and R. norvegicus, lung volume was similar to reported data, although values were lower than expected.

Reducing Contingency through Sampling at the Luckey FUSRAP Site - 13186

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

Frothingham, David; Barker, Michelle; Buechi, Steve

2013-07-01

Typically, the greatest risk in developing accurate cost estimates for the remediation of hazardous, toxic, and radioactive waste sites is the uncertainty in the estimated volume of contaminated media requiring remediation. Efforts to address this risk in the remediation cost estimate can result in large cost contingencies that are often considered unacceptable when budgeting for site cleanups. Such was the case for the Luckey Formerly Utilized Sites Remedial Action Program (FUSRAP) site near Luckey, Ohio, which had significant uncertainty surrounding the estimated volume of site soils contaminated with radium, uranium, thorium, beryllium, and lead. Funding provided by the American Recoverymore » and Reinvestment Act (ARRA) allowed the U.S. Army Corps of Engineers (USACE) to conduct additional environmental sampling and analysis at the Luckey Site between November 2009 and April 2010, with the objective to further delineate the horizontal and vertical extent of contaminated soils in order to reduce the uncertainty in the soil volume estimate. Investigative work included radiological, geophysical, and topographic field surveys, subsurface borings, and soil sampling. Results from the investigative sampling were used in conjunction with Argonne National Laboratory's Bayesian Approaches for Adaptive Spatial Sampling (BAASS) software to update the contaminated soil volume estimate for the site. This updated volume estimate was then used to update the project cost-to-complete estimate using the USACE Cost and Schedule Risk Analysis process, which develops cost contingencies based on project risks. An investment of $1.1 M of ARRA funds for additional investigative work resulted in a reduction of 135,000 in-situ cubic meters (177,000 in-situ cubic yards) in the estimated base volume estimate. This refinement of the estimated soil volume resulted in a $64.3 M reduction in the estimated project cost-to-complete, through a reduction in the uncertainty in the contaminated soil volume estimate and the associated contingency costs. (authors)« less

Unbiased estimation of the calcaneus volume using the Cavalieri principle on computed tomography images.

PubMed

Acer, N; Bayar, B; Basaloglu, H; Oner, E; Bayar, K; Sankur, S

2008-11-20

The size and shape of tarsal bones are especially relevant when considering some orthopedic diseases such as clubfoot. For this reason, the measurements of the tarsal bones have been the subject of many studies, none of which has used stereological methods to estimate the volume. In the present stereological study, we estimated the volume of calcaneal bone of normal feet and dry bones. We used a combination of the Cavalieri principle and computer tomographic scans taken from eight males and nine dry calcanei to estimate the volumes of calcaneal bones. The mean volume of dry calcaneal bones was estimated, producing mean results using the point-counting method and Archimedes principle being 49.11+/-10.7 or 48.22+/-11.92 cm(3), respectively. A positive correlation was found between anthropometric measurements and the volume of calcaneal bones. The findings of the present study using the stereological methods could provide data for the evaluation of normal and pathological volumes of calcaneal bones.

The international food unit: a new measurement aid that can improve portion size estimation.

PubMed

Bucher, T; Weltert, M; Rollo, M E; Smith, S P; Jia, W; Collins, C E; Sun, M

2017-09-12

Portion size education tools, aids and interventions can be effective in helping prevent weight gain. However consumers have difficulties in estimating food portion sizes and are confused by inconsistencies in measurement units and terminologies currently used. Visual cues are an important mediator of portion size estimation, but standardized measurement units are required. In the current study, we present a new food volume estimation tool and test the ability of young adults to accurately quantify food volumes. The International Food Unit™ (IFU™) is a 4x4x4 cm cube (64cm 3 ), subdivided into eight 2 cm sub-cubes for estimating smaller food volumes. Compared with currently used measures such as cups and spoons, the IFU™ standardizes estimation of food volumes with metric measures. The IFU™ design is based on binary dimensional increments and the cubic shape facilitates portion size education and training, memory and recall, and computer processing which is binary in nature. The performance of the IFU™ was tested in a randomized between-subject experiment (n = 128 adults, 66 men) that estimated volumes of 17 foods using four methods; the IFU™ cube, a deformable modelling clay cube, a household measuring cup or no aid (weight estimation). Estimation errors were compared between groups using Kruskall-Wallis tests and post-hoc comparisons. Estimation errors differed significantly between groups (H(3) = 28.48, p < .001). The volume estimations were most accurate in the group using the IFU™ cube (Mdn = 18.9%, IQR = 50.2) and least accurate using the measuring cup (Mdn = 87.7%, IQR = 56.1). The modelling clay cube led to a median error of 44.8% (IQR = 41.9). Compared with the measuring cup, the estimation errors using the IFU™ were significantly smaller for 12 food portions and similar for 5 food portions. Weight estimation was associated with a median error of 23.5% (IQR = 79.8). The IFU™ improves volume estimation accuracy compared to other methods. The cubic shape was perceived as favourable, with subdivision and multiplication facilitating volume estimation. Further studies should investigate whether the IFU™ can facilitate portion size training and whether portion size education using the IFU™ is effective and sustainable without the aid. A 3-dimensional IFU™ could serve as a reference object for estimating food volume.

Using LiDAR to Estimate Surface Erosion Volumes within the Post-storm 2012 Bagley Fire

NASA Astrophysics Data System (ADS)

Mikulovsky, R. P.; De La Fuente, J. A.; Mondry, Z. J.

2014-12-01

The total post-storm 2012 Bagley fire sediment budget of the Squaw Creek watershed in the Shasta-Trinity National Forest was estimated using many methods. A portion of the budget was quantitatively estimated using LiDAR. Simple workflows were designed to estimate the eroded volume's of debris slides, fill failures, gullies, altered channels and streams. LiDAR was also used to estimate depositional volumes. Thorough manual mapping of large erosional features using the ArcGIS 10.1 Geographic Information System was required as these mapped features determined the eroded volume boundaries in 3D space. The 3D pre-erosional surface for each mapped feature was interpolated based on the boundary elevations. A surface difference calculation was run using the estimated pre-erosional surfaces and LiDAR surfaces to determine volume of sediment potentially delivered into the stream system. In addition, cross sections of altered channels and streams were taken using stratified random selection based on channel gradient and stream order respectively. The original pre-storm surfaces of channel features were estimated using the cross sections and erosion depth criteria. Open source software Inkscape was used to estimate cross sectional areas for randomly selected channel features and then averaged for each channel gradient and stream order classes. The average areas were then multiplied by the length of each class to estimate total eroded altered channel and stream volume. Finally, reservoir and in-channel depositional volumes were estimated by mapping channel forms and generating specific reservoir elevation zones associated with depositional events. The in-channel areas and zones within the reservoir were multiplied by estimated and field observed sediment thicknesses to attain a best guess sediment volume. In channel estimates included re-occupying stream channel cross sections established before the fire. Once volumes were calculated, other erosion processes of the Bagley sedimentation study, such as surface soil erosion were combined to estimate the total fire and storm sediment budget for the Squaw Creek watershed. The LiDAR-based measurement workflows can be easily applied to other sediment budget studies using one high resolution LiDAR dataset.

Water activity and mobility in solutions of glycerol and small molecular weight sugars: Implication for cryo- and lyopreservation

NASA Astrophysics Data System (ADS)

He, Xiaoming; Fowler, Alex; Toner, Mehmet

2006-10-01

In this study, the free volume models, originally developed for large molecular weight polymer-solvent systems, were used to study the water activity and mobility in solutions of four small molecular weight cryo-/lyoprotectants, viz., glycerol, a monosaccharide (fructose), and two disaccharides (sucrose and trehalose). The free volume model parameters were determined by fitting the models to available experimental data using a nonlinear optimization procedure. It was found that free volume models could accurately predict the available experimental data, which suggests that the free volume models might be generally applicable to aqueous solutions of small molecular weight cryo-/lyoprotectants. Furthermore, several models for estimating the mutual diffusion coefficient were tested using available experimental data for aqueous solutions of glycerol and a better method to estimate the mutual diffusion coefficient was proposed. Free volume models were used to predict and analyze the water activity and mobility in solutions of four cryo-/lyoprotectants under conditions frequently encountered in cryo-/lyopreservation applications. It was found that the water mobility in the glassy state of the above four solutions is essentially negligible in the case of cryopreservation with storage temperature lower than -110°C. However, the water mobility in a glass at higher temperature (>-80°C) may be significant. As a result, a subcooling of up to 50°C may be necessary for the long-term cryo-/lyopreservation of biomaterials depending on the water content and the type of cryo-/lyoprotectants. It was further shown that trehalose might be the best of the four protectants studied for lyopreservation (water mass fraction ⩽0.1) when the storage temperature is above the room temperature. The results from this study might be useful for the development of more effective protocols for both cryopreservation and lyopreservation of living cells and other biomaterials.

Accuracy of Standing-Tree Volume Estimates Based on McClure Mirror Caliper Measurements

Treesearch

Noel D. Cost

1971-01-01

The accuracy of standing-tree volume estimates, calculated from diameter measurements taken by a mirror caliper and with sectional aluminum poles for height control, was compared with volume estimates calculated from felled-tree measurements. Twenty-five trees which varied in species, size, and form were used in the test. The results showed that two estimates of total...

Direct and simultaneous estimation of cardiac four chamber volumes by multioutput sparse regression.

PubMed

Zhen, Xiantong; Zhang, Heye; Islam, Ali; Bhaduri, Mousumi; Chan, Ian; Li, Shuo

2017-02-01

Cardiac four-chamber volume estimation serves as a fundamental and crucial role in clinical quantitative analysis of whole heart functions. It is a challenging task due to the huge complexity of the four chambers including great appearance variations, huge shape deformation and interference between chambers. Direct estimation has recently emerged as an effective and convenient tool for cardiac ventricular volume estimation. However, existing direct estimation methods were specifically developed for one single ventricle, i.e., left ventricle (LV), or bi-ventricles; they can not be directly used for four chamber volume estimation due to the great combinatorial variability and highly complex anatomical interdependency of the four chambers. In this paper, we propose a new, general framework for direct and simultaneous four chamber volume estimation. We have addressed two key issues, i.e., cardiac image representation and simultaneous four chamber volume estimation, which enables accurate and efficient four-chamber volume estimation. We generate compact and discriminative image representations by supervised descriptor learning (SDL) which can remove irrelevant information and extract discriminative features. We propose direct and simultaneous four-chamber volume estimation by the multioutput sparse latent regression (MSLR), which enables jointly modeling nonlinear input-output relationships and capturing four-chamber interdependence. The proposed method is highly generalized, independent of imaging modalities, which provides a general regression framework that can be extensively used for clinical data prediction to achieve automated diagnosis. Experiments on both MR and CT images show that our method achieves high performance with a correlation coefficient of up to 0.921 with ground truth obtained manually by human experts, which is clinically significant and enables more accurate, convenient and comprehensive assessment of cardiac functions. Copyright © 2016 Elsevier B.V. All rights reserved.

Estimating the volume of glaciers in the Himalayan-Karakoram region using different methods

NASA Astrophysics Data System (ADS)

Frey, H.; Machguth, H.; Huss, M.; Huggel, C.; Bajracharya, S.; Bolch, T.; Kulkarni, A.; Linsbauer, A.; Salzmann, N.; Stoffel, M.

2014-12-01

Ice volume estimates are crucial for assessing water reserves stored in glaciers. Due to its large glacier coverage, such estimates are of particular interest for the Himalayan-Karakoram (HK) region. In this study, different existing methodologies are used to estimate the ice reserves: three area-volume relations, one slope-dependent volume estimation method, and two ice-thickness distribution models are applied to a recent, detailed, and complete glacier inventory of the HK region, spanning over the period 2000-2010 and revealing an ice coverage of 40 775 km2. An uncertainty and sensitivity assessment is performed to investigate the influence of the observed glacier area and important model parameters on the resulting total ice volume. Results of the two ice-thickness distribution models are validated with local ice-thickness measurements at six glaciers. The resulting ice volumes for the entire HK region range from 2955 to 4737 km3, depending on the approach. This range is lower than most previous estimates. Results from the ice thickness distribution models and the slope-dependent thickness estimations agree well with measured local ice thicknesses. However, total volume estimates from area-related relations are larger than those from other approaches. The study provides evidence on the significant effect of the selected method on results and underlines the importance of a careful and critical evaluation.

Reproducibility of isopach data and estimates of dispersal and eruption volumes

NASA Astrophysics Data System (ADS)

Klawonn, M.; Houghton, B. F.; Swanson, D.; Fagents, S. A.; Wessel, P.; Wolfe, C. J.

2012-12-01

Total erupted volume and deposit thinning relationships are key parameters in characterizing explosive eruptions and evaluating the potential risk from a volcano as well as inputs to volcanic plume models. Volcanologists most commonly estimate these parameters by hand-contouring deposit data, then representing these contours in thickness versus square root area plots, fitting empirical laws to the thinning relationships and integrating over the square root area to arrive at volume estimates. In this study we analyze the extent to which variability in hand-contouring thickness data for pyroclastic fall deposits influences the resulting estimates and investigate the effects of different fitting laws. 96 volcanologists (3% MA students, 19% PhD students, 20% postdocs, 27% professors, and 30% professional geologists) from 11 countries (Australia, Ecuador, France, Germany, Iceland, Italy, Japan, New Zealand, Switzerland, UK, USA) participated in our study and produced hand-contours on identical maps using our unpublished thickness measurements of the Kilauea Iki 1959 fall deposit. We computed volume estimates by (A) integrating over a surface fitted through the contour lines, as well as using the established methods of integrating over the thinning relationships of (B) an exponential fit with one to three segments, (C) a power law fit, and (D) a Weibull function fit. To focus on the differences from the hand-contours of the well constrained deposit and eliminate the effects of extrapolations to great but unmeasured thicknesses near the vent, we removed the volume contribution of the near vent deposit (defined as the deposit above 3.5 m) from the volume estimates. The remaining volume approximates to 1.76 *106 m3 (geometric mean for all methods) with maximum and minimum estimates of 2.5 *106 m3 and 1.1 *106 m3. Different integration methods of identical isopach maps result in volume estimate differences of up to 50% and, on average, maximum variation between integration methods of 14%. Volume estimates with methods (A), (C) and (D) show strong correlation (r = 0.8 to r = 0.9), while correlation of (B) with the other methods is weaker (r = 0.2 to r = 0.6) and correlation between (B) and (C) is not statistically significant. We find that the choice of larger maximum contours leads to smaller volume estimates due to method (C), but larger estimates with the other methods. We do not find statistically significant correlation between volume estimations and participants experience level, number of chosen contour levels, nor smoothness of contours. Overall, application of the different methods to the same maps leads to similar mean volume estimates, but the different methods show different dependencies and varying spread of volume estimates. The results indicate that these key parameters are less critically dependent on the operator and their choices of contour values, intervals etc., and more sensitive to the selection of technique to integrate these data.

Cost Analysis of an Air Brayton Receiver for a Solar Thermal Electric Power System in Selected Annual Production Volumes

NASA Technical Reports Server (NTRS)

1981-01-01

Pioneer Engineering and Manufacturing Company estimated the cost of manufacturing and Air Brayton Receiver for a Solar Thermal Electric Power System as designed by the AiResearch Division of the Garrett Corporation. Production costs were estimated at annual volumes of 100; 1,000; 5,000; 10,000; 50,000; 100,000 and 1,000,000 units. These costs included direct labor, direct material and manufacturing burden. A make or buy analysis was made of each part of each volume. At high volumes special fabrication concepts were used to reduce operation cycle times. All costs were estimated at an assumed 100% plant capacity. Economic feasibility determined the level of production at which special concepts were to be introduced. Estimated costs were based on the economics of the last half of 1980. Tooling and capital equipment costs were estimated for ach volume. Infrastructure and personnel requirements were also estimated.

A comparison of estimates of statewide pleasure trip volume and expenditures derived from telephone versus mail surveys

Treesearch

Dae-Kwan Kim; Daniel M. Spotts; Donald F. Holecek

1998-01-01

This paper compares estimates of pleasure trip volume and expenditures derived from a regional telephone survey to those derived from the TravelScope mail panel survey. Significantly different estimates emerged, suggesting that survey-based estimates of pleasure trip volume and expenditures, at least in the case of the two surveys examined, appear to be affected by...

Timber resource statistics for the Upper Yukon inventory unit, Alaska, 1980.

Treesearch

Willem W.S. van Hees

1987-01-01

The 1980 inventory of the forest resources of the Upper Yukon unit was designed to produce inventory estimates of timberland area, volume of timber, and volumes of timber growth and mortality. Timberland area is estimated at 742,000 acres. Cubic-foot volume on all timberland is estimated at 475 million cubic feet. Timber growth and mortality are estimated at -615,000...

Overcoming bias in estimating the volume-outcome relationship.

PubMed

Tsai, Alexander C; Votruba, Mark; Bridges, John F P; Cebul, Randall D

2006-02-01

To examine the effect of hospital volume on 30-day mortality for patients with congestive heart failure (CHF) using administrative and clinical data in conventional regression and instrumental variables (IV) estimation models. The primary data consisted of longitudinal information on comorbid conditions, vital signs, clinical status, and laboratory test results for 21,555 Medicare-insured patients aged 65 years and older hospitalized for CHF in northeast Ohio in 1991-1997. The patient was the primary unit of analysis. We fit a linear probability model to the data to assess the effects of hospital volume on patient mortality within 30 days of admission. Both administrative and clinical data elements were included for risk adjustment. Linear distances between patients and hospitals were used to construct the instrument, which was then used to assess the endogeneity of hospital volume. When only administrative data elements were included in the risk adjustment model, the estimated volume-outcome effect was statistically significant (p=.029) but small in magnitude. The estimate was markedly attenuated in magnitude and statistical significance when clinical data were added to the model as risk adjusters (p=.39). IV estimation shifted the estimate in a direction consistent with selective referral, but we were unable to reject the consistency of the linear probability estimates. Use of only administrative data for volume-outcomes research may generate spurious findings. The IV analysis further suggests that conventional estimates of the volume-outcome relationship may be contaminated by selective referral effects. Taken together, our results suggest that efforts to concentrate hospital-based CHF care in high-volume hospitals may not reduce mortality among elderly patients.

Estimating Lake Volume from Limited Data: A Simple GIS Approach

EPA Science Inventory

Lake volume provides key information for estimating residence time or modeling pollutants. Methods for calculating lake volume have relied on dated technologies (e.g. planimeters) or used potentially inaccurate assumptions (e.g. volume of a frustum of a cone). Modern GIS provid...

Procedural volume, cost, and reimbursement of outpatient incisional hernia repair: implications for payers and providers.

PubMed

Song, Chao; Liu, Emelline; Tackett, Scott; Shi, Lizheng; Marcus, Daniel

2017-06-01

This analysis aimed to evaluate trends in volumes and costs of primary elective incisional ventral hernia repairs (IVHRs) and investigated potential cost implications of moving procedures from inpatient to outpatient settings. A time series study was conducted using the Premier Hospital Perspective ® Database (Premier database) for elective IVHR identified by International Classification of Diseases, Ninth revision, Clinical Modification codes. IVHR procedure volumes and costs were determined for inpatient, outpatient, minimally invasive surgery (MIS), and open procedures from January 2008-June 2015. Initial visit costs were inflation-adjusted to 2015 US dollars. Median costs were used to analyze variation by site of care and payer. Quantile regression on median costs was conducted in covariate-adjusted models. Cost impact of potential outpatient migration was estimated from a Medicare perspective. During the study period, the trend for outpatient procedures in obese and non-obese populations increased. Inpatient and outpatient MIS procedures experienced a steady growth in adoption over their open counterparts. Overall median costs increased over time, and inpatient costs were often double outpatient costs. An economic model demonstrated that a 5% shift of inpatient procedures to outpatient MIS procedures can have a cost surplus of ∼ US $1.8 million for provider or a cost-saving impact of US $1.7 million from the Centers for Medicare & Medicaid Services perspective. The study was limited by information in the Premier database. No data were available for IVHR cases performed in free-standing ambulatory surgery centers or federal healthcare facilities. Volumes and costs of outpatient IVHRs and MIS procedures increased from January 2008-June 2015. Median costs were significantly higher for inpatients than outpatients, and the difference was particularly evident for obese patients. A substantial cost difference between inpatient and outpatient MIS cases indicated a financial benefit for shifting from inpatient to outpatient MIS.

Working Time in Comparative Perspective. Volume I: Patterns, Trends, and the Policy Implications for Earnings Inequality and Unemployment.

ERIC Educational Resources Information Center

Wong, Ging, Ed.; Picot, Garnett, Ed.

This is the first of two volumes of selected papers presented at the 1996 conference on "Changes in Working Time in Canada and the United States." Eleven chapters focus on weekly hours worked by individuals, including the recent changes in the distribution of weekly working time in Canada and the U.S., implications of the changing…

Using Photogrammetry to Estimate Tank Waste Volumes from Video

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

Field, Jim G.

Washington River Protection Solutions (WRPS) contracted with HiLine Engineering & Fabrication, Inc. to assess the accuracy of photogrammetry tools as compared to video Camera/CAD Modeling System (CCMS) estimates. This test report documents the results of using photogrammetry to estimate the volume of waste in tank 241-C-I04 from post-retrieval videos and results using photogrammetry to estimate the volume of waste piles in the CCMS test video.

Estimation of truck volumes and flows

DOT National Transportation Integrated Search

2004-08-01

This research presents a statistical approach for estimating truck volumes, based : primarily on classification counts and information on roadway functionality, employment, : sales volume and number of establishments within the state. Models have bee...

Estimation of gas and tissue lung volumes by MRI: functional approach of lung imaging.

PubMed

Qanadli, S D; Orvoen-Frija, E; Lacombe, P; Di Paola, R; Bittoun, J; Frija, G

1999-01-01

The purpose of this work was to assess the accuracy of MRI for the determination of lung gas and tissue volumes. Fifteen healthy subjects underwent MRI of the thorax and pulmonary function tests [vital capacity (VC) and total lung capacity (TLC)] in the supine position. MR examinations were performed at inspiration and expiration. Lung volumes were measured by a previously validated technique on phantoms. Both individual and total lung volumes and capacities were calculated. MRI total vital capacity (VC(MRI)) was compared with spirometric vital capacity (VC(SP)). Capacities were correlated to lung volumes. Tissue volume (V(T)) was estimated as the difference between the total lung volume at full inspiration and the TLC. No significant difference was seen between VC(MRI) and VC(SP). Individual capacities were well correlated (r = 0.9) to static volume at full inspiration. The V(T) was estimated to be 836+/-393 ml. This preliminary study demonstrates that MRI can accurately estimate lung gas and tissue volumes. The proposed approach appears well suited for functional imaging of the lung.

Using GIS to Estimate Lake Volume from Limited Data (Lake and Reservoir Management)

EPA Science Inventory

Estimates of lake volume are necessary for calculating residence time and modeling pollutants. Modern GIS methods for calculating lake volume improve upon more dated technologies (e.g. planimeters) and do not require potentially inaccurate assumptions (e.g. volume of a frustum of...

Estimating merchantable volumes of second growth Douglas-fir stands from total cubic volume and associated stand characteristics.

Treesearch

Richard L. Williamson; Robert O. Curtis

1980-01-01

Equations are given for estimating merchantable volumes of second-growth Douglas-fir stands to specified breast-high and top-diameter limits, in cubic feet or board feet, from total volume in cubic feet and certain associated stand characteristics.

Spatially- explicit Fossil Fuel Carbon Dioxide Inventories for Transportation in the U.S.

NASA Astrophysics Data System (ADS)

Hutchins, M.; Gurney, K. R.

2016-12-01

The transportation sector is the second largest source of Fossil Fuel CO2 (FFCO2) emissions, and is unique in that federal, state, and municipal levels of government are all able to enact transportation policy. However, since data related to transportation activities are reported by multiple different government agencies, the data are not always consistent. As a result, the methods and data used to inventory and account for transportation related FFCO2 emissions have important implications for both science and policy. Aggregate estimates of transportation related FFCO2 emissions can be spatially distributed using traffic data, such as the Highway Performance Monitoring System (HPMS) Average Annual Daily Traffic (AADT). There are currently two datasets that estimate the spatial distribution of transportation related FFCO2 in the United States- Vulcan 3.0 and the Database of Road Transportation Emissions (DARTE). Both datasets are at 1 km resolution, for the year 2011, and utilize HPMS AADT traffic data. However, Vulcan 3.0 and DARTE spatially distribute emissions using different methods and inputs, resulting in a number of differences. Vulcan 3.0 and DARTE estimate national transportation related FFCO2 emissions within 2.5% of each other, with more significant differences at the county and state level. The differences are most notable in urban versus rural regions, and for specific road classes. The origin of these differences are explored in depth to understand the implication of using specific data sources, such as the National Emissions Inventory and other aggregate transportation statistics from the Federal Highway Administration (FHWA). In addition to comparing Vulcan 3.0 and DARTE to each other, the results from both data sets are compared to independent traffic volume measurements acquired from the FHWA Continuous Count Station (CCS) network. The CCS records hourly traffic counts at fixed locations in space throughout the U.S. We calculate transportation related FFCO2 emissions at a CCS stations using fuel specific emissions factors combined with the raw traffic counts. The CCS network provides a unique opportunity to compare spatially explicit, "bottom-up" models of transportation related FFCO2 emissions to measured traffic volume at over 300 specific locations.

WE-G-BRD-08: Motion Analysis for Rectal Cancer: Implications for Adaptive Radiotherapy On the MR-Linac

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

Kleijnen, J; Asselen, B van; Burbach, M

2015-06-15

Purpose: Purpose of this study is to find the optimal trade-off between adaptation interval and margin reduction and to define the implications of motion for rectal cancer boost radiotherapy on a MR-linac. Methods: Daily MRI scans were acquired of 16 patients, diagnosed with rectal cancer, prior to each radiotherapy fraction in one week (N=76). Each scan session consisted of T2-weighted and three 2D sagittal cine-MRI, at begin (t=0 min), middle (t=9:30 min) and end (t=18:00 min) of scan session, for 1 minute at 2 Hz temporal resolution. Tumor and clinical target volume (CTV) were delineated on each T2-weighted scan andmore » transferred to each cine-MRI. The start frame of the begin scan was used as reference and registered to frames at time-points 15, 30 and 60 seconds, 9:30 and 18:00 minutes and 1, 2, 3 and 4 days later. Per time-point, motion of delineated voxels was evaluated using the deformation vector fields of the registrations and the 95th percentile distance (dist95%) was calculated as measure of motion. Per time-point, the distance that includes 90% of all cases was taken as estimate of required planning target volume (PTV)-margin. Results: Highest motion reduction is observed going from 9:30 minutes to 60 seconds. We observe a reduction in margin estimates from 10.6 to 2.7 mm and 16.1 to 4.6 mm for tumor and CTV, respectively, when adapting every 60 seconds compared to not adapting treatment. A 75% and 71% reduction, respectively. Further reduction in adaptation time-interval yields only marginal motion reduction. For adaptation intervals longer than 18:00 minutes only small motion reductions are observed. Conclusion: The optimal adaptation interval for adaptive rectal cancer (boost) treatments on a MR-linac is 60 seconds. This results in substantial smaller PTV-margin estimates. Adaptation intervals of 18:00 minutes and higher, show little improvement in motion reduction.« less

Bunte Breccia of the Ries - Continuous deposits of large impact craters

NASA Technical Reports Server (NTRS)

Horz, F.; Ostertag, R.; Rainey, D. A.

1983-01-01

The 26-km-diameter Ries impact crater in south Germany and the mechanism of ejection and emplacement associated with its formation about 15 Myr ago are discussed in detail, and the implications of the findings for models of crater formation on earth, moon, and planets are considered. Field observations and laboratory tests on 560-m core materials from nine locations are reported. The continuous deposits (Bunte Breccia) are found to be a chaotic mixture resulting from deposition at ambient temperatures in a highly turbulent environment, probably in the ballistic scenario proposed by Oberbeck et al. (1975), with an emplacement time of only about 5 min. Further impact parameters are estimated using the 'Z model' of Maxwell (1977): initial radius = 6.5 km, excavation depth = 1650 m, excavation volume = 136 cu km, and transient cavity volume = 230 cu km. The interpretation of lunar and planetary remote-sensing and in situ evidence from impact craters is reviewed in the light of the Ries findings. Numerous photographs, maps, diagrams, and tables illustrate the investigation.

Exploring Dutch surgeons' views on volume-based policies: a qualitative interview study.

PubMed

Mesman, Roos; Faber, Marjan J; Westert, Gert P; Berden, Bart

2018-01-01

Objective In many countries, the evidence for volume-outcome associations in surgery has been transferred into policy. Despite the large body of research that exists on the topic, qualitative studies aimed at surgeons' views on, and experiences with, these volume-based policies are lacking. We interviewed Dutch surgeons to gain more insight into the implications of volume-outcome policies for daily clinical practice, as input for effective surgical quality improvement. Methods Semi-structured interviews were conducted with 20 purposively selected surgeons from a stratified sample for hospital type and speciality. The interviews were recorded, transcribed verbatim and underwent inductive content analysis. Results Two overarching themes were inductively derived from the data: (1) minimum volume standards and (2) implications of volume-based policies. Although surgeons acknowledged the premise 'more is better', they were critical about the validity and underlying evidence for minimum volume standards. Patients often inquire about caseload, which is met with both understanding and discomfort. Surgeons offered many examples of controversies surrounding the process of determining thresholds as well as the ways in which health insurers use volume as a purchasing criterion. Furthermore, being held accountable for caseload may trigger undesired strategic behaviour, such as unwarranted operations. Volume-based policies also have implications for the survival of low-volume providers and affect patient travel times, although the latter is not necessarily problematic in the Dutch context. Conclusions Surgeons in this study acknowledged that more volume leads to better quality. However, validity issues, undesired strategic behaviour and the ways in which minimum volume standards are established and applied have made surgeons critical of current policy practice. These findings suggest that volume remains a controversial quality measure and causes polarization that is not conducive to a collective effort for quality improvement. We recommend enforcing thresholds that are based on the best achievable level of consensus and assessing additional criteria when passing judgement on quality of care.

Accuracy and variability of tumor burden measurement on multi-parametric MRI

NASA Astrophysics Data System (ADS)

Salarian, Mehrnoush; Gibson, Eli; Shahedi, Maysam; Gaed, Mena; Gómez, José A.; Moussa, Madeleine; Romagnoli, Cesare; Cool, Derek W.; Bastian-Jordan, Matthew; Chin, Joseph L.; Pautler, Stephen; Bauman, Glenn S.; Ward, Aaron D.

2014-03-01

Measurement of prostate tumour volume can inform prognosis and treatment selection, including an assessment of the suitability and feasibility of focal therapy, which can potentially spare patients the deleterious side effects of radical treatment. Prostate biopsy is the clinical standard for diagnosis but provides limited information regarding tumour volume due to sparse tissue sampling. A non-invasive means for accurate determination of tumour burden could be of clinical value and an important step toward reduction of overtreatment. Multi-parametric magnetic resonance imaging (MPMRI) is showing promise for prostate cancer diagnosis. However, the accuracy and inter-observer variability of prostate tumour volume estimation based on separate expert contouring of T2-weighted (T2W), dynamic contrastenhanced (DCE), and diffusion-weighted (DW) MRI sequences acquired using an endorectal coil at 3T is currently unknown. We investigated this question using a histologic reference standard based on a highly accurate MPMRIhistology image registration and a smooth interpolation of planimetric tumour measurements on histology. Our results showed that prostate tumour volumes estimated based on MPMRI consistently overestimated histological reference tumour volumes. The variability of tumour volume estimates across the different pulse sequences exceeded interobserver variability within any sequence. Tumour volume estimates on DCE MRI provided the lowest inter-observer variability and the highest correlation with histology tumour volumes, whereas the apparent diffusion coefficient (ADC) maps provided the lowest volume estimation error. If validated on a larger data set, the observed correlations could support the development of automated prostate tumour volume segmentation algorithms as well as correction schemes for tumour burden estimation on MPMRI.

Brain Volume Estimation Enhancement by Morphological Image Processing Tools.

PubMed

Zeinali, R; Keshtkar, A; Zamani, A; Gharehaghaji, N

2017-12-01

Volume estimation of brain is important for many neurological applications. It is necessary in measuring brain growth and changes in brain in normal/abnormal patients. Thus, accurate brain volume measurement is very important. Magnetic resonance imaging (MRI) is the method of choice for volume quantification due to excellent levels of image resolution and between-tissue contrast. Stereology method is a good method for estimating volume but it requires to segment enough MRI slices and have a good resolution. In this study, it is desired to enhance stereology method for volume estimation of brain using less MRI slices with less resolution. In this study, a program for calculating volume using stereology method has been introduced. After morphologic method, dilation was applied and the stereology method enhanced. For the evaluation of this method, we used T1-wighted MR images from digital phantom in BrainWeb which had ground truth. The volume of 20 normal brain extracted from BrainWeb, was calculated. The volumes of white matter, gray matter and cerebrospinal fluid with given dimension were estimated correctly. Volume calculation from Stereology method in different cases was made. In three cases, Root Mean Square Error (RMSE) was measured. Case I with T=5, d=5, Case II with T=10, D=10 and Case III with T=20, d=20 (T=slice thickness, d=resolution as stereology parameters). By comparing these results of two methods, it is obvious that RMSE values for our proposed method are smaller than Stereology method. Using morphological operation, dilation allows to enhance the estimation volume method, Stereology. In the case with less MRI slices and less test points, this method works much better compared to Stereology method.

Asymmetric Effects of Subaerial and Subaqueous Basement Slopes on Self-Similar Morphology of Prograding Deltas

NASA Astrophysics Data System (ADS)

Lai, Steven Yueh Jen; Hsiao, Yung-Tai; Wu, Fu-Chun

2017-12-01

Deltas form over basements of various slope configurations. While the morphodynamics of prograding deltas over single-slope basements have been studied previously, our understanding of delta progradation over segmented basements is still limited. Here we use experimental and analytical approaches to investigate the deltaic morphologies developing over two-slope basements with unequal subaerial and subaqueous slopes. For each case considered, the scaled profiles of the evolving delta collapse to a single profile for constant water and sediment influxes, allowing us to use the analytical self-similar profiles to investigate the individual effects of subaerial/subaqueous slopes. Individually varying the subaerial/subaqueous slopes exerts asymmetric effects on the morphologies. Increasing the subaerial slope advances the entire delta; increasing the subaqueous slope advances the upstream boundary of the topset yet causes the downstream boundary to retreat. The delta front exhibits a first-retreat-then-advance migrating trend with increasing subaqueous slope. A decrease in subaerial topset length is always accompanied by an increase in subaqueous volume fraction, no matter which segment is steepened. Applications are presented for estimating shoreline retreat caused by steepening of basement slopes, and estimating subaqueous volume and delta front using the observed topset length. The results may have implications for real-world delta systems subjected to upstream tectonic uplift and/or downstream subsidence. Both scenarios would exhibit reduced topset lengths, which are indicative of the accompanied increases in subaqueous volume and signal tectonic uplift and/or subsidence that are at play. We highlight herein the importance of geometric controls on partitioning of sediment between subaerial and subaqueous delta components.

CT-based renal volume and graft function after living-donor kidney transplantation: Is there a volume threshold to avoid?

PubMed

Dias, Jorge; Malheiro, Jorge; Almeida, Manuela; Dias, Leonídio; Silva-Ramos, Miguel; Martins, La Salete; Xambre, Luís; Castro-Henriques, António

2015-05-01

Donated kidney volume influences post-transplant outcomes and graft survival. We evaluated the relationship between living-donor kidney volume and recipient graft function at 12 months post-transplantation, exploring a volume threshold for a suboptimal graft function, and compared two different formulas of volume estimation. A retrospective analysis of 82 pairs of living-donor kidney transplants was conducted. Donor renal volumes were estimated from computerized tomography scans using the ellipsoid formula and the voxel counting technique. Linear and restricted cubic regression spline was used to analyze the association of volume with graft function. Additionally, we determined the correlation between the two volume estimation formulas and established a correction factor for the ellipsoid formula. Renal volume (adjusted to recipient BSA) had the strongest independent effect (B = 1.65 per 10 ml/m(2) increase, p value <0.001) on graft function at 12 months. The eGFR at 12 months was 52.5, 63.6 and 67.6 ml/min/1.73 m(2) for the low, medium and high volume ratio terciles, respectively (p value <0.001). The odds of a GFR <50 ml/min became significantly reduced with volumes above 145 cc/1.73 m(2). A strong positive correlation between the two formulas was identified (R(2) = 0.705), but the optimal correction factor for our cohort was 0.566. In a Caucasian population, higher donor kidney volumes estimated from preoperative CT scans are associated with higher recipient eGFRs at 12 months after live-donor transplantation. Using this criterion, transplant teams can potentially improve selection of living donors if multiple donors are available. However, the need for precise estimation of donor kidney volumes should not be overlooked.

Radiation dose from MDCT using Monte Carlo simulations: estimating fetal dose due to pulmonary embolism scans accounting for overscan

NASA Astrophysics Data System (ADS)

Angel, E.; Wellnitz, C.; Goodsitt, M.; DeMarco, J.; Cagnon, C.; Ghatali, M.; Cody, D.; Stevens, D.; McCollough, C.; Primak, A.; McNitt-Gray, M.

2007-03-01

Pregnant women with shortness of breath are increasingly referred for CT Angiography to rule out Pulmonary Embolism (PE). While this exam is typically focused on the lungs, extending scan boundaries and overscan can add to the irradiated volume and have implications on fetal dose. The purpose of this work was to estimate radiation dose to the fetus when various levels of overscan were encountered. Two voxelized models of pregnant patients derived from actual patient anatomy were created based on image data. The models represent an early (< 7 weeks) and late term pregnancy (36 weeks). A previously validated Monte Carlo model of an MDCT scanner was used that takes into account physical details of the scanner. Simulated helical scans used 120 kVp, 4x5 mm beam collimation, pitch 1, and varying beam-off locations (edge of the irradiated volume) were used to represent different protocols plus overscan. Normalized dose (mGy/100mAs) was calculated for each fetus. For the early term and the late term pregnancy models, fetal dose estimates for a standard thoracic PE exam were estimated to be 0.05 and 0.3 mGy/100mAs, respectively, increasing to 9 mGy/100mAs when the beam-off location was extended to encompass the fetus. When performing PE exams to rule out PE in pregnant patients, the beam-off location may have a large effect on fetal dose, especially for late term pregnancies. Careful consideration of ending location of the x-ray beam - and not the end of image data - could result in significant reduction in radiation dose to the fetus.

Controls on Arctic sea ice from first-year and multi-year ice survival rates

NASA Astrophysics Data System (ADS)

Armour, K.; Bitz, C. M.; Hunke, E. C.; Thompson, L.

2009-12-01

The recent decrease in Arctic sea ice cover has transpired with a significant loss of multi-year (MY) ice. The transition to an Arctic that is populated by thinner first-year (FY) sea ice has important implications for future trends in area and volume. We develop a reduced model for Arctic sea ice with which we investigate how the survivability of FY and MY ice control various aspects of the sea-ice system. We demonstrate that Arctic sea-ice area and volume behave approximately as first-order autoregressive processes, which allows for a simple interpretation of September sea-ice in which its mean state, variability, and sensitivity to climate forcing can be described naturally in terms of the average survival rates of FY and MY ice. This model, used in concert with a sea-ice simulation that traces FY and MY ice areas to estimate the survival rates, reveals that small trends in the ice survival rates explain the decline in total Arctic ice area, and the relatively larger loss of MY ice area, over the period 1979-2006. Additionally, our model allows for a calculation of the persistence time scales of September area and volume anomalies. A relatively short memory time scale for ice area (~ 1 year) implies that Arctic ice area is nearly in equilibrium with long-term climate forcing at all times, and therefore observed trends in area are a clear indication of a changing climate. A longer memory time scale for ice volume (~ 5 years) suggests that volume can be out of equilibrium with climate forcing for long periods of time, and therefore trends in ice volume are difficult to distinguish from its natural variability. With our reduced model, we demonstrate the connection between memory time scale and sensitivity to climate forcing, and discuss the implications that a changing memory time scale has on the trajectory of ice area and volume in a warming climate. Our findings indicate that it is unlikely that a “tipping point” in September ice area and volume will be reached as the climate is further warmed. Finally, we suggest novel model validation techniques based upon comparing the characteristics of FY and MY ice within models to observations. We propose that keeping an account of FY and MY ice area within sea ice models offers a powerful new way to evaluate model projections of sea ice in a greenhouse warming climate.

Aerial photo volume tables for Douglas-fir in the Pacific Northwest.

Treesearch

Robert B. Pope

1961-01-01

The aerial photo volume tables in this report are tools to be used in obtaining better timber inventories. Volume estimates based on tables such as these, properly field checked, are generally cheaper than ground cruises of comparable accuracy. Photo volume tables also permit rough volume estimates to be made from aerial photos alone when limited time, bad weather, or...

Estimating volume, biomass, and potential emissions of hand-piled fuels

Treesearch

Clinton S. Wright; Cameron S. Balog; Jeffrey W. Kelly

2009-01-01

Dimensions, volume, and biomass were measured for 121 hand-constructed piles composed primarily of coniferous (n = 63) and shrub/hardwood (n = 58) material at sites in Washington and California. Equations using pile dimensions, shape, and type allow users to accurately estimate the biomass of hand piles. Equations for estimating true pile volume from simple geometric...

Estimating bark thicknesses of common Appalachian hardwoods

Treesearch

R. Edward Thomas; Neal D. Bennett

2014-01-01

Knowing the thickness of bark along the stem of a tree is critical to accurately estimate residue and, more importantly, estimate the volume of solid wood available. Determining the volume or weight of bark for a log is important because bark and wood mass are typically separated while processing logs, and accurate determination of volume is problematic. Bark thickness...

Survival suit volume reduction associated with immersion: implications for buoyancy estimation in offshore workers of different size.

PubMed

Stewart, Arthur; Ledingham, Robert; Furnace, Graham; Williams, Hector; Coleshaw, Susan

2017-06-01

It is currently unknown how body size affects buoyancy in submerged helicopter escape. Eight healthy males aged 39.6 ± 12.6 year (mean ± SD) with BMI 22.0-40.0 kg m -2 wearing a standard survival ('dry') suit undertook a normal venting manoeuvre and underwent 3D scanning to assess body volume (wearing the suit) before and after immersion in a swimming pool. Immersion-induced volume loss averaged 14.4 ± 5.4 l, decreased with increasing dry density (mass volume -1 ) and theoretical buoyant force in 588 UK offshore workers was found to be 264 ± 46 and 232 ± 60 N using linear and power functions, respectively. Both approaches revealed heavier workers to have greater buoyant force. While a larger sample may yield a more accurate buoyancy prediction, this study shows heavier workers are likely to have greater buoyancy. Without free-swimming capability to overcome such buoyancy, some individuals may possibly exceed the safe limit to enable escape from a submerged helicopter. Practitioner Summary: Air expulsion reduced total body volume of survival-suited volunteers following immersion by an amount inversely proportional to body size. When applied to 588 offshore workers, the predicted air loss suggested buoyant force to be greatest in the heaviest individuals, which may impede their ability to exit a submerged helicopter.

Assessment of costs and benefits of flexible and alternative fuel use in the US transportation sector

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

None

1993-01-01

The primary objective of this report is to provide estimates of volumes and development costs of known nonassociated gas reserves in selected, potentially important supplier nations, using a standard set of costing algorithms and conventions. Estimates of undeveloped nonassociated gas reserves and the cost of drilling development wells, production equipment, gas processing facilities, and pipeline construction are made at the individual field level. A discounted cash-flow model of production, investment, and expenses is used to estimate the present value cost of developing each field on a per-thousand-cubic-foot (Mcf) basis. These gas resource cost estimates for individual accumulations (that is, fieldsmore » or groups of fields) then were aggregated into country-specific price-quantity curves. These curves represent the cost of developing and transporting natural gas to an export point suitable for tanker shipments or to a junction with a transmission line. The additional costs of LNG or methanol conversion are not included. A brief summary of the cost of conversion to methanol and transportation to the United States is contained in Appendix D: Implications of Gas Development Costs for Methanol Conversion.« less

Block Volume Estimation from the Discontinuity Spacing Measurements of Mesozoic Limestone Quarries, Karaburun Peninsula, Turkey

PubMed Central

Elci, Hakan; Turk, Necdet

2014-01-01

Block volumes are generally estimated by analyzing the discontinuity spacing measurements obtained either from the scan lines placed over the rock exposures or the borehole cores. Discontinuity spacing measurements made at the Mesozoic limestone quarries in Karaburun Peninsula were used to estimate the average block volumes that could be produced from them using the suggested methods in the literature. The Block Quality Designation (BQD) ratio method proposed by the authors has been found to have given in the same order of the rock block volume to the volumetric joint count (J v) method. Moreover, dimensions of the 2378 blocks produced between the years of 2009 and 2011 in the working quarries have been recorded. Assuming, that each block surfaces is a discontinuity, the mean block volume (V b), the mean volumetric joint count (J vb) and the mean block shape factor of the blocks are determined and compared with the estimated mean in situ block volumes (V in) and volumetric joint count (J vi) values estimated from the in situ discontinuity measurements. The established relations are presented as a chart to be used in practice for estimating the mean volume of blocks that can be obtained from a quarry site by analyzing the rock mass discontinuity spacing measurements. PMID:24696642

Block volume estimation from the discontinuity spacing measurements of mesozoic limestone quarries, Karaburun Peninsula, Turkey.

PubMed

Elci, Hakan; Turk, Necdet

2014-01-01

Block volumes are generally estimated by analyzing the discontinuity spacing measurements obtained either from the scan lines placed over the rock exposures or the borehole cores. Discontinuity spacing measurements made at the Mesozoic limestone quarries in Karaburun Peninsula were used to estimate the average block volumes that could be produced from them using the suggested methods in the literature. The Block Quality Designation (BQD) ratio method proposed by the authors has been found to have given in the same order of the rock block volume to the volumetric joint count (J(v)) method. Moreover, dimensions of the 2378 blocks produced between the years of 2009 and 2011 in the working quarries have been recorded. Assuming, that each block surfaces is a discontinuity, the mean block volume (V(b)), the mean volumetric joint count (J(vb)) and the mean block shape factor of the blocks are determined and compared with the estimated mean in situ block volumes (V(in)) and volumetric joint count (J(vi)) values estimated from the in situ discontinuity measurements. The established relations are presented as a chart to be used in practice for estimating the mean volume of blocks that can be obtained from a quarry site by analyzing the rock mass discontinuity spacing measurements.

Vestibular schwannomas: Accuracy of tumor volume estimated by ice cream cone formula using thin-sliced MR images.

PubMed

Ho, Hsing-Hao; Li, Ya-Hui; Lee, Jih-Chin; Wang, Chih-Wei; Yu, Yi-Lin; Hueng, Dueng-Yuan; Ma, Hsin-I; Hsu, Hsian-He; Juan, Chun-Jung

2018-01-01

We estimated the volume of vestibular schwannomas by an ice cream cone formula using thin-sliced magnetic resonance images (MRI) and compared the estimation accuracy among different estimating formulas and between different models. The study was approved by a local institutional review board. A total of 100 patients with vestibular schwannomas examined by MRI between January 2011 and November 2015 were enrolled retrospectively. Informed consent was waived. Volumes of vestibular schwannomas were estimated by cuboidal, ellipsoidal, and spherical formulas based on a one-component model, and cuboidal, ellipsoidal, Linskey's, and ice cream cone formulas based on a two-component model. The estimated volumes were compared to the volumes measured by planimetry. Intraobserver reproducibility and interobserver agreement was tested. Estimation error, including absolute percentage error (APE) and percentage error (PE), was calculated. Statistical analysis included intraclass correlation coefficient (ICC), linear regression analysis, one-way analysis of variance, and paired t-tests with P < 0.05 considered statistically significant. Overall tumor size was 4.80 ± 6.8 mL (mean ±standard deviation). All ICCs were no less than 0.992, suggestive of high intraobserver reproducibility and high interobserver agreement. Cuboidal formulas significantly overestimated the tumor volume by a factor of 1.9 to 2.4 (P ≤ 0.001). The one-component ellipsoidal and spherical formulas overestimated the tumor volume with an APE of 20.3% and 29.2%, respectively. The two-component ice cream cone method, and ellipsoidal and Linskey's formulas significantly reduced the APE to 11.0%, 10.1%, and 12.5%, respectively (all P < 0.001). The ice cream cone method and other two-component formulas including the ellipsoidal and Linskey's formulas allow for estimation of vestibular schwannoma volume more accurately than all one-component formulas.

Regional body volumes, BMI, waist circumference, and percentage fat in severely obese adults.

PubMed

Wang, Jack; Gallagher, Dympna; Thornton, John C; Yu, Wen; Weil, Rich; Kovac, Betty; Pi-Sunyer, F Xavier

2007-11-01

This study presents total body volume (TBV) and regional body volume, and their relationships with widely used body composition indices [BMI, waist circumference (WC), and percentage body fat (% fat)] in severely obese adults (BMI >or=35 kg/m(2)). We measured TBV, trunk volume (TV), arm volume (AV), leg volume (LV), and WC and estimated % fat in 32 severely obese persons with BMI 36 to 62 kg/m(2) (23 women; age, 19 to 65 years; weight, 91 to 182 kg) and in 58 persons with BMI <35 kg/m(2) (28 women; age, 18 to 83 years; weight, 48 to 102 kg) using a newly validated 3-day photonic image scanner (3DPS, Model C9036-02, Hamamatsu Co., Japan) and calculated TV/TBV, AV/TBV, and LV/TBV. Men had significantly larger TBV and higher TV/TBV and AV/TBV, but significantly lower LV/TBV than women, independently of BMI. TV/TBV increased while AV/TBV and LV/TBV decreased with increasing BMI, WC, and % fat, and the rate of increase in TV/TBV per % fat was significantly greater in severely obese individuals than in individuals with BMI <35 kg/m(2). The relationships for TBV with % fat were much lower than with BMI or WC. Body volume gains were mainly in the trunk region in adults, irrespective of sex or BMI. For a given BMI, WC, or % fat, men had a significantly larger TV than women. The implication is that men could have higher health risks due to having higher trunk body weight as a proportion of total body weight compared with severely obese or less severely obese women.

Monitoring needs and goal-directed fluid therapy within an enhanced recovery program.

PubMed

Minto, Gary; Scott, Michael J; Miller, Timothy E

2015-03-01

Patients having major abdominal surgery need perioperative fluid supplementation; however, enhanced recovery principles mitigate against many of the factors that traditionally led to relative hypovolemia in the perioperative period. An estimate of fluid requirements for abdominal surgery can be made but individualization of fluid prescription requires consideration of clinical signs and hemodynamic variables. The literature supports goal-directed fluid therapy. Application of this evidence to justify stroke volume optimization in the setting of major surgery within an enhanced recovery program is controversial. This article places the evidence in context, reviews controversies, and suggests implications for current practice and future research. Copyright © 2015 Elsevier Inc. All rights reserved.

Abdominal fat volume estimation by stereology on CT: a comparison with manual planimetry.

PubMed

Manios, G E; Mazonakis, M; Voulgaris, C; Karantanas, A; Damilakis, J

2016-03-01

To deploy and evaluate a stereological point-counting technique on abdominal CT for the estimation of visceral (VAF) and subcutaneous abdominal fat (SAF) volumes. Stereological volume estimations based on point counting and systematic sampling were performed on images from 14 consecutive patients who had undergone abdominal CT. For the optimization of the method, five sampling intensities in combination with 100 and 200 points were tested. The optimum stereological measurements were compared with VAF and SAF volumes derived by the standard technique of manual planimetry on the same scans. Optimization analysis showed that the selection of 200 points along with the sampling intensity 1/8 provided efficient volume estimations in less than 4 min for VAF and SAF together. The optimized stereology showed strong correlation with planimetry (VAF: r = 0.98; SAF: r = 0.98). No statistical differences were found between the two methods (VAF: P = 0.81; SAF: P = 0.83). The 95% limits of agreement were also acceptable (VAF: -16.5%, 16.1%; SAF: -10.8%, 10.7%) and the repeatability of stereology was good (VAF: CV = 4.5%, SAF: CV = 3.2%). Stereology may be successfully applied to CT images for the efficient estimation of abdominal fat volume and may constitute a good alternative to the conventional planimetric technique. Abdominal obesity is associated with increased risk of disease and mortality. Stereology may quantify visceral and subcutaneous abdominal fat accurately and consistently. The application of stereology to estimating abdominal volume fat reduces processing time. Stereology is an efficient alternative method for estimating abdominal fat volume.

Estimates of plasma, packed cell and total blood volume in tissues of the rainbow trout (Salmo gairdneri)

USGS Publications Warehouse

Gingerich, W.H.; Pityer, R.A.; Rach, J.J.

1987-01-01

1. Total blood volume and relative blood volumes in selected tissues were determined in non-anesthetized, confined rainbow trout by using 51Cr-labelled trout erythrocytes as a vascular space marker.2. Mean total blood volume was estimated to be 4.09 ± 0.55 ml/100 g, or about 75% of that estimated with the commonly used plasma space marker Evans blue dye.3. Relative tissue blood volumes were greatest in highly perfused tissues such as kidney, gills, brain and liver and least in mosaic muscle.4. Estimates of tissue vascular spaces, made using radiolabelled erythrocytes, were only 25–50% of those based on plasma space markers.5. The consistently smaller vascular volumes obtained with labelled erythrocytes could be explained by assuming that commonly used plasma space markers diffuse from the vascular compartment.

Estimating tree bole volume using artificial neural network models for four species in Turkey.

PubMed

Ozçelik, Ramazan; Diamantopoulou, Maria J; Brooks, John R; Wiant, Harry V

2010-01-01

Tree bole volumes of 89 Scots pine (Pinus sylvestris L.), 96 Brutian pine (Pinus brutia Ten.), 107 Cilicica fir (Abies cilicica Carr.) and 67 Cedar of Lebanon (Cedrus libani A. Rich.) trees were estimated using Artificial Neural Network (ANN) models. Neural networks offer a number of advantages including the ability to implicitly detect complex nonlinear relationships between input and output variables, which is very helpful in tree volume modeling. Two different neural network architectures were used and produced the Back propagation (BPANN) and the Cascade Correlation (CCANN) Artificial Neural Network models. In addition, tree bole volume estimates were compared to other established tree bole volume estimation techniques including the centroid method, taper equations, and existing standard volume tables. An overview of the features of ANNs and traditional methods is presented and the advantages and limitations of each one of them are discussed. For validation purposes, actual volumes were determined by aggregating the volumes of measured short sections (average 1 meter) of the tree bole using Smalian's formula. The results reported in this research suggest that the selected cascade correlation artificial neural network (CCANN) models are reliable for estimating the tree bole volume of the four examined tree species since they gave unbiased results and were superior to almost all methods in terms of error (%) expressed as the mean of the percentage errors. 2009 Elsevier Ltd. All rights reserved.

New 40Ar/ 39Ar dating of the Grande Ronde lavas, Columbia River Basalts, USA: Implications for duration of flood basalt eruption episodes

NASA Astrophysics Data System (ADS)

Barry, T. L.; Self, S.; Kelley, S. P.; Reidel, S.; Hooper, P.; Widdowson, M.

2010-08-01

Grande Ronde Basalt (GRB) lavas represent the most voluminous eruptive pulse of the Columbia River-Snake River-Yellowstone hotspot volcanism. With an estimated eruptive volume of 150,000 km 3, GRB lavas form at least 66% of the total volume of the Columbia River Basalt Group. New 40Ar/ 39Ar dates for GRB lavas reveal they were emplaced within a maximum period of 0.42 ± 0.18 My. A well-documented stratigraphy indicates at least 110 GRB flow fields (or individual eruptions), and on this basis suggests an average inter-eruption hiatus of less than 4000 years. Isotopic age-dating cannot resolve time gaps between GRB eruptions, and it is difficult to otherwise form a picture of the durations of eruptions because of non-uniform weathering in the top of flow fields and a general paucity of sediments between GR lavas. Where sediment has formed on top of GRB lavas, it varies in thickness from zero to 20-30 cm of silty to fine-sandy material, with occasional diatomaceous sediment. Individual GRB eruptions varied considerably in volume but many were greater than 1000 km 3 in size. Most probably eruptive events were not equally spaced in time; some eruptions may have followed short periods of volcanic repose (perhaps 10 2 to 10 3 of years), whilst others could have been considerably longer (many 1000 s to > 10 4 years). Recent improvements in age-dating for other continental flood basalt (CFB) lava sequences have yielded estimates of total eruptive durations of less than 1 My for high-volume pulses of lava production. The GRB appears to be a similar example, where the main pulse occupied a brief period. Even allowing for moderate to long-duration pahoehoe flow field production, the amount of time the system spends in active lava-producing mode is small — less than c. 2.6% (based on eruption durations of approximately 10,000 years, compared to the duration of the entire eruptive pulse of c. 420,000 years). A review of available 40Ar/ 39Ar data for the major voluminous phases of the Columbia River Basalt Group suggests that activity of the Steens Basalt-Imnaha Basalt-GRB may have, at times, been simultaneous, with obvious implications for climatic effects. Resolving intervals between successive eruptions during CFB province construction, and durations of main eruptive pulses, remains vital to determining the environmental impact of these huge eruptions.

Inference for lidar-assisted estimation of forest growing stock volume

Treesearch

Ronald E. McRoberts; Erik Næsset; Terje Gobakken

2013-01-01

Estimates of growing stock volume are reported by the national forest inventories (NFI) of most countries and may serve as the basis for aboveground biomass and carbon estimates as required by an increasing number of international agreements. The probability-based (design-based) statistical estimators traditionally used by NFIs to calculate estimates are generally...

Higher cost of implementing Xpert(®) MTB/RIF in Ugandan peripheral settings: implications for cost-effectiveness.

PubMed

Hsiang, E; Little, K M; Haguma, P; Hanrahan, C F; Katamba, A; Cattamanchi, A; Davis, J L; Vassall, A; Dowdy, D

2016-09-01

Initial cost-effectiveness evaluations of Xpert(®) MTB/RIF for tuberculosis (TB) diagnosis have not fully accounted for the realities of implementation in peripheral settings. To evaluate costs and diagnostic outcomes of Xpert testing implemented at various health care levels in Uganda. We collected empirical cost data from five health centers utilizing Xpert for TB diagnosis, using an ingredients approach. We reviewed laboratory and patient records to assess outcomes at these sites and10 sites without Xpert. We also estimated incremental cost-effectiveness of Xpert testing; our primary outcome was the incremental cost of Xpert testing per newly detected TB case. The mean unit cost of an Xpert test was US$21 based on a mean monthly volume of 54 tests per site, although unit cost varied widely (US$16-58) and was primarily determined by testing volume. Total diagnostic costs were 2.4-fold higher in Xpert clinics than in non-Xpert clinics; however, Xpert only increased diagnoses by 12%. The diagnostic costs of Xpert averaged US$119 per newly detected TB case, but were as high as US$885 at the center with the lowest volume of tests. Xpert testing can detect TB cases at reasonable cost, but may double diagnostic budgets for relatively small gains, with cost-effectiveness deteriorating with lower testing volumes.

Improved interpolation of meteorological forcings for hydrologic applications in a Swiss Alpine region

NASA Astrophysics Data System (ADS)

Tobin, Cara; Nicotina, Ludovico; Parlange, Marc B.; Berne, Alexis; Rinaldo, Andrea

2011-04-01

SummaryThis paper presents a comparative study on the mapping of temperature and precipitation fields in complex Alpine terrain. Its relevance hinges on the major impact that inadequate interpolations of meteorological forcings bear on the accuracy of hydrologic predictions regardless of the specifics of the models, particularly during flood events. Three flood events measured in the Swiss Alps are analyzed in detail to determine the interpolation methods which best capture the distribution of intense, orographically-induced precipitation. The interpolation techniques comparatively examined include: Inverse Distance Weighting (IDW), Ordinary Kriging (OK), and Kriging with External Drift (KED). Geostatistical methods rely on a robust anisotropic variogram for the definition of the spatial rainfall structure. Results indicate that IDW tends to significantly underestimate rainfall volumes whereas OK and KED methods capture spatial patterns and rainfall volumes induced by storm advection. Using numerical weather forecasts and elevation data as covariates for precipitation, we provide evidence for KED to outperform the other methods. Most significantly, the use of elevation as auxiliary information in KED of temperatures demonstrates minimal errors in estimated instantaneous rainfall volumes and provides instantaneous lapse rates which better capture snow/rainfall partitioning. Incorporation of the temperature and precipitation input fields into a hydrological model used for operational management was found to provide vastly improved outputs with respect to measured discharge volumes and flood peaks, with notable implications for flood modeling.

Pricing hospital care: Global budgets and marginal pricing strategies.

PubMed

Sutherland, Jason M

2015-08-01

The Canadian province of British Columbia (BC) is adding financial incentives to increase the volume of surgeries provided by hospitals using a marginal pricing approach. The objective of this study is to calculate marginal costs of surgeries based on assumptions regarding hospitals' availability of labor and equipment. This study is based on observational clinical, administrative and financial data generated by hospitals. Hospital inpatient and outpatient discharge summaries from the province are linked with detailed activity-based costing information, stratified by assigned case mix categorizations. To reflect a range of operating constraints governing hospitals' ability to increase their volume of surgeries, a number of scenarios are proposed. Under these scenarios, estimated marginal costs are calculated and compared to prices being offered as incentives to hospitals. Existing data can be used to support alternative strategies for pricing hospital care. Prices for inpatient surgeries do not generate positive margins under a range of operating scenarios. Hip and knee surgeries generate surpluses for hospitals even under the most costly labor conditions and are expected to generate additional volume. In health systems that wish to fine-tune financial incentives, setting prices that create incentives for additional volume should reflect knowledge of hospitals' underlying cost structures. Possible implications of mis-pricing include no response to the incentives or uneven increases in supply. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

The cosmic X-ray background-IRAS galaxy correlation and the local X-ray volume emissivity

NASA Technical Reports Server (NTRS)

Miyaji, Takamitsu; Lahav, Ofer; Jahoda, Keith; Boldt, Elihu

1994-01-01

We have cross-correlated the galaxies from the IRAS 2 Jy redshift survey sample and the 0.7 Jy projected sample with the all-sky cosmic X-ray background (CXB) map obtained from the High Energy Astronomy Observatory (HEAO) 1 A-2 experiment. We have detected a significant correlation signal between surface density of IRAS galaxies and the X-ray background intensity, with W(sub xg) = (mean value of ((delta I)(delta N)))/(mean value of I)(mean value of N)) of several times 10(exp -3). While this correlation signal has a significant implication for the contribution of the local universe to the hard (E greater than 2 keV) X-ray background, its interpretation is model-dependent. We have developed a formulation to model the cross-correlation between CXB surface brightness and galaxy counts. This includes the effects of source clustering and the X-ray-far-infrared luminosity correlation. Using an X-ray flux-limited sample of active galactic nuclei (AGNs), which has IRAS 60 micrometer measurements, we have estimated the contribution of the AGN component to the observed CXB-IRAS galaxy count correlations in order to see whether there is an excess component, i.e., contribution from low X-ray luminosity sources. We have applied both the analytical approach and Monte Carlo simulations for the estimations. Our estimate of the local X-ray volume emissivity in the 2-10 keV band is rho(sub x) approximately = (4.3 +/- 1.2) x 10(exp 38) h(sub 50) ergs/s/cu Mpc, consistent with the value expected from the luminosity function of AGNs alone. This sets a limit to the local volume emissivity from lower luminosity sources (e.g., star-forming galaxies, low-ionization nuclear emission-line regions (LINERs)) to rho(sub x) less than or approximately = 2 x 10(exp 38) h(sub 50) ergs/s/cu Mpc.

Determination of fractional flow reserve (FFR) based on scaling laws: a simulation study

NASA Astrophysics Data System (ADS)

Wong, Jerry T.; Molloi, Sabee

2008-07-01

Fractional flow reserve (FFR) provides an objective physiological evaluation of stenosis severity. A technique that can measure FFR using only angiographic images would be a valuable tool in the cardiac catheterization laboratory. To perform this, the diseased blood flow can be measured with a first pass distribution analysis and the theoretical normal blood flow can be estimated from the total coronary arterial volume based on scaling laws. A computer simulation of the coronary arterial network was used to gain a better understanding of how hemodynamic conditions and coronary artery disease can affect blood flow, arterial volume and FFR estimation. Changes in coronary arterial flow and volume due to coronary stenosis, aortic pressure and venous pressure were examined to evaluate the potential use of flow and volume for FFR determination. This study showed that FFR can be estimated using arterial volume and a scaling coefficient corrected for aortic pressure. However, variations in venous pressure were found to introduce some error in FFR estimation. A relative form of FFR was introduced and was found to cancel out the influence of pressure on coronary flow, arterial volume and FFR estimation. The use of coronary flow and arterial volume for FFR determination appears promising.

Estimation of volume and mass and of changes in volume and mass of selected chat piles in the Picher mining district, Ottawa County, Oklahoma, 2005-10

USGS Publications Warehouse

Smith, S. Jerrod

2013-01-01

From the 1890s through the 1970s the Picher mining district in northeastern Ottawa County, Oklahoma, was the site of mining and processing of lead and zinc ore. When mining ceased in about 1979, as much as 165–300 million tons of mine tailings, locally referred to as “chat,” remained in the Picher mining district. Since 1979, some chat piles have been mined for aggregate materials and have decreased in volume and mass. Currently (2013), the land surface in the Picher mining district is covered by thousands of acres of chat, much of which remains on Indian trust land owned by allottees. The Bureau of Indian Affairs manages these allotted lands and oversees the sale and removal of chat from these properties. To help the Bureau of Indian Affairs better manage the sale and removal of chat, the U.S. Geological Survey, in cooperation with the Bureau of Indian Affairs, estimated the 2005 and 2010 volumes and masses of selected chat piles remaining on allotted lands in the Picher mining district. The U.S. Geological Survey also estimated the changes in volume and mass of these chat piles for the period 2005 through 2010. The 2005 and 2010 chat-pile volume and mass estimates were computed for 34 selected chat piles on 16 properties in the study area. All computations of volume and mass were performed on individual chat piles and on groups of chat piles in the same property. The Sooner property had the greatest estimated volume (4.644 million cubic yards) and mass (5.253 ± 0.473 million tons) of chat in 2010. Five of the selected properties (Sooner, Western, Lawyers, Skelton, and St. Joe) contained estimated chat volumes exceeding 1 million cubic yards and estimated chat masses exceeding 1 million tons in 2010. Four of the selected properties (Lucky Bill Humbah, Ta Mee Heh, Bird Dog, and St. Louis No. 6) contained estimated chat volumes of less than 0.1 million cubic yards and estimated chat masses of less than 0.1 million tons in 2010. The total volume of all selected chat piles was estimated to be 18.073 million cubic yards in 2005 and 16.171 million cubic yards in 2010. The total mass of all selected chat piles was estimated to be 20.445 ± 1.840 million tons in 2005 and 18.294 ± 1.646 million tons in 2010. All of the selected chat piles decreased in volume and mass for the period 2005 through 2010. Chat piles CP022 (Ottawa property) and CP013 (Sooner property) had some within-property chat-pile redistribution, with both chat piles having net decreases in volume and mass for the period 2005 through 2010. The Sooner property and the St. Joe property had the greatest volume (and mass) changes, with 1.266 million cubic yards and 0.217 million cubic yards (1.432 ± 0.129 million tons and 0.246 ± 0.022 million tons) of chat being removed, respectively. The chat removed from the Sooner and St. Joe properties accounts for about 78 percent of the chat removed from all selected chat piles and properties. The total volume and mass removed from all selected chat piles for the period 2005 through 2010 were estimated to be 1.902 million cubic yards and 2.151 ± 0.194 million tons, respectively.

Using Mobile Device Samples to Estimate Traffic Volumes

DOT National Transportation Integrated Search

2017-12-01

In this project, TTI worked with StreetLight Data to evaluate a beta version of its traffic volume estimates derived from global positioning system (GPS)-based mobile devices. TTI evaluated the accuracy of average annual daily traffic (AADT) volume :...

Comparison of estimated and observed stormwater runoff for fifteen watersheds in west-central Florida, using five common design techniques

USGS Publications Warehouse

Trommer, J.T.; Loper, J.E.; Hammett, K.M.; Bowman, Georgia

1996-01-01

Hydrologists use several traditional techniques for estimating peak discharges and runoff volumes from ungaged watersheds. However, applying these techniques to watersheds in west-central Florida requires that empirical relationships be extrapolated beyond tested ranges. As a result there is some uncertainty as to their accuracy. Sixty-six storms in 15 west-central Florida watersheds were modeled using (1) the rational method, (2) the U.S. Geological Survey regional regression equations, (3) the Natural Resources Conservation Service (formerly the Soil Conservation Service) TR-20 model, (4) the Army Corps of Engineers HEC-1 model, and (5) the Environmental Protection Agency SWMM model. The watersheds ranged between fully developed urban and undeveloped natural watersheds. Peak discharges and runoff volumes were estimated using standard or recommended methods for determining input parameters. All model runs were uncalibrated and the selection of input parameters was not influenced by observed data. The rational method, only used to calculate peak discharges, overestimated 45 storms, underestimated 20 storms and estimated the same discharge for 1 storm. The mean estimation error for all storms indicates the method overestimates the peak discharges. Estimation errors were generally smaller in the urban watersheds and larger in the natural watersheds. The U.S. Geological Survey regression equations provide peak discharges for storms of specific recurrence intervals. Therefore, direct comparison with observed data was limited to sixteen observed storms that had precipitation equivalent to specific recurrence intervals. The mean estimation error for all storms indicates the method overestimates both peak discharges and runoff volumes. Estimation errors were smallest for the larger natural watersheds in Sarasota County, and largest for the small watersheds located in the eastern part of the study area. The Natural Resources Conservation Service TR-20 model, overestimated peak discharges for 45 storms and underestimated 21 storms, and overestimated runoff volumes for 44 storms and underestimated 22 storms. The mean estimation error for all storms modeled indicates that the model overestimates peak discharges and runoff volumes. The smaller estimation errors in both peak discharges and runoff volumes were for storms occurring in the urban watersheds, and the larger errors were for storms occurring in the natural watersheds. The HEC-1 model overestimated peak discharge rates for 55 storms and underestimated 11 storms. Runoff volumes were overestimated for 44 storms and underestimated for 22 storms using the Army Corps of Engineers HEC-1 model. The mean estimation error for all the storms modeled indicates that the model overestimates peak discharge rates and runoff volumes. Generally, the smaller estimation errors in peak discharges were for storms occurring in the urban watersheds, and the larger errors were for storms occurring in the natural watersheds. Estimation errors in runoff volumes; however, were smallest for the 3 natural watersheds located in the southernmost part of Sarasota County. The Environmental Protection Agency Storm Water Management model produced similar peak discharges and runoff volumes when using both the Green-Ampt and Horton infiltration methods. Estimated peak discharge and runoff volume data calculated with the Horton method was only slightly higher than those calculated with the Green-Ampt method. The mean estimation error for all the storms modeled indicates the model using the Green-Ampt infiltration method overestimates peak discharges and slightly underestimates runoff volumes. Using the Horton infiltration method, the model overestimates both peak discharges and runoff volumes. The smaller estimation errors in both peak discharges and runoff volumes were for storms occurring in the five natural watersheds in Sarasota County with the least amount of impervious cover and the lowest slopes. The largest er

Facial Emotion Recognition Impairments are Associated with Brain Volume Abnormalities in Individuals with HIV

PubMed Central

Clark, Uraina S.; Walker, Keenan A.; Cohen, Ronald A.; Devlin, Kathryn N.; Folkers, Anna M.; Pina, Mathew M.; Tashima, Karen T.

2015-01-01

Impaired facial emotion recognition abilities in HIV+ patients are well documented, but little is known about the neural etiology of these difficulties. We examined the relation of facial emotion recognition abilities to regional brain volumes in 44 HIV-positive (HIV+) and 44 HIV-negative control (HC) adults. Volumes of structures implicated in HIV− associated neuropathology and emotion recognition were measured on MRI using an automated segmentation tool. Relative to HC, HIV+ patients demonstrated emotion recognition impairments for fearful expressions, reduced anterior cingulate cortex (ACC) volumes, and increased amygdala volumes. In the HIV+ group, fear recognition impairments correlated significantly with ACC, but not amygdala volumes. ACC reductions were also associated with lower nadir CD4 levels (i.e., greater HIV-disease severity). These findings extend our understanding of the neurobiological substrates underlying an essential social function, facial emotion recognition, in HIV+ individuals and implicate HIV-related ACC atrophy in the impairment of these abilities. PMID:25744868

Lunar Architecture Team - Phase 2 Habitat Volume Estimation: "Caution When Using Analogs"

NASA Technical Reports Server (NTRS)

Rudisill, Marianne; Howard, Robert; Griffin, Brand; Green, Jennifer; Toups, Larry; Kennedy, Kriss

2008-01-01

The lunar surface habitat will serve as the astronauts' home on the moon, providing a pressurized facility for all crew living functions and serving as the primary location for a number of crew work functions. Adequate volume is required for each of these functions in addition to that devoted to housing the habitat systems and crew consumables. The time constraints of the LAT-2 schedule precluded the Habitation Team from conducting a complete "bottoms-up" design of a lunar surface habitation system from which to derive true volumetric requirements. The objective of this analysis was to quickly derive an estimated total pressurized volume and pressurized net habitable volume per crewmember for a lunar surface habitat, using a principled, methodical approach in the absence of a detailed design. Five "heuristic methods" were used: historical spacecraft volumes, human/spacecraft integration standards and design guidance, Earth-based analogs, parametric "sizing" tools, and conceptual point designs. Estimates for total pressurized volume, total habitable volume, and volume per crewmember were derived using these methods. All method were found to provide some basis for volume estimates, but values were highly variable across a wide range, with no obvious convergence of values. Best current assumptions for required crew volume were provided as a range. Results of these analyses and future work are discussed.

CT volumetry of the skeletal tissues

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

Brindle, James M.; Alexandre Trindade, A.; Pichardo, Jose C.

2006-10-15

Computed tomography (CT) is an important and widely used modality in the diagnosis and treatment of various cancers. In the field of molecular radiotherapy, the use of spongiosa volume (combined tissues of the bone marrow and bone trabeculae) has been suggested as a means to improve the patient-specificity of bone marrow dose estimates. The noninvasive estimation of an organ volume comes with some degree of error or variation from the true organ volume. The present study explores the ability to obtain estimates of spongiosa volume or its surrogate via manual image segmentation. The variation among different segmentation raters was exploredmore » and found not to be statistically significant (p value >0.05). Accuracy was assessed by having several raters manually segment a polyvinyl chloride (PVC) pipe with known volumes. Segmentation of the outer region of the PVC pipe resulted in mean percent errors as great as 15% while segmentation of the pipe's inner region resulted in mean percent errors within {approx}5%. Differences between volumes estimated with the high-resolution CT data set (typical of ex vivo skeletal scans) and the low-resolution CT data set (typical of in vivo skeletal scans) were also explored using both patient CT images and a PVC pipe phantom. While a statistically significant difference (p value <0.002) between the high-resolution and low-resolution data sets was observed with excised femoral heads obtained following total hip arthroplasty, the mean difference between high-resolution and low-resolution data sets was found to be only 1.24 and 2.18 cm{sup 3} for spongiosa and cortical bone, respectively. With respect to differences observed with the PVC pipe, the variation between the high-resolution and low-resolution mean percent errors was a high as {approx}20% for the outer region volume estimates and only as high as {approx}6% for the inner region volume estimates. The findings from this study suggest that manual segmentation is a reasonably accurate and reliable means for the in vivo estimation of spongiosa volume. This work also provides a foundation for future studies where spongiosa volumes are estimated by various raters in more comprehensive CT data sets.« less

Estimating aspen volume and weight for individual trees, diameter classes, or entire stands.

Treesearch

Bryce E. Schlaegel

1975-01-01

Presents allometric volume and weight equations for Minnesota quaking aspen. Volume, green weight, and dry weight estimates can be made for wood, bark, and limbs on the basis of individual trees, diameter classes, or entire stands.

Critical length sampling: a method to estimate the volume of downed coarse woody debris

Treesearch

G& #246; ran St& #229; hl; Jeffrey H. Gove; Michael S. Williams; Mark J. Ducey

2010-01-01

In this paper, critical length sampling for estimating the volume of downed coarse woody debris is presented. Using this method, the volume of downed wood in a stand can be estimated by summing the critical lengths of down logs included in a sample obtained using a relascope or wedge prism; typically, the instrument should be tilted 90° from its usual...

Effects of Measurement Errors on Individual Tree Stem Volume Estimates for the Austrian National Forest Inventory

Treesearch

Ambros Berger; Thomas Gschwantner; Ronald E. McRoberts; Klemens Schadauer

2014-01-01

National forest inventories typically estimate individual tree volumes using models that rely on measurements of predictor variables such as tree height and diameter, both of which are subject to measurement error. The aim of this study was to quantify the impacts of these measurement errors on the uncertainty of the model-based tree stem volume estimates. The impacts...

Comparison of estimates of hardwood bole volume using importance sampling, the centroid method, and some taper equations

Treesearch

Harry V., Jr. Wiant; Michael L. Spangler; John E. Baumgras

2002-01-01

Various taper systems and the centroid method were compared to unbiased volume estimates made by importance sampling for 720 hardwood trees selected throughout the state of West Virginia. Only the centroid method consistently gave volumes estimates that did not differ significantly from those made by importance sampling, although some taper equations did well for most...

Earth's Constant Mean Elevation: Implication for Long-Term Sea Level and Controlled by Ocean Lithosphere Dynamics in a Pitman World

NASA Astrophysics Data System (ADS)

Rowley, David

2017-04-01

On a spherical Earth, the mean elevation ( -2440m) would be everywhere at a mean Earth radius from the center. This directly links an elevation at the surface to physical dimensions of the Earth, including surface area and volume that are at most very slowly evolving components of the Earth system. Earth's mean elevation thus provides a framework within which to consider changes in heights of Earth's solid surface as a function of time. In this paper the focus will be on long-term, non-glacially controlled sea level. Long-term sea level has long been argued to be largely controlled by changes in ocean basin volume related to changes in area-age distribution of oceanic lithosphere. As generally modeled by Pitman (1978) and subsequent workers, the age-depth relationship of oceanic lithosphere, including both the ridge depth and coefficients describing the age-depth relationship are assumed constant. This paper examines the consequences of adhering to these assumptions when placed within the larger framework of maintaining a constant mean radius of the Earth. Self-consistent estimates of long-term sea level height and changes in mean depth of the oceanic crust are derived from the assumption that the mean elevation and corresponding mean radius are unchanging aspects of Earth's shorter-term evolution. Within this context, changes in mean depth of the oceanic crust, corresponding with changes in mean age of the oceanic lithosphere, acting over the area of the oceanic crust represent a volume change that is required to be balanced by a compensating equal but opposite volume change under the area of the continental crust. Models of paleo-cumulative hypsometry derived from a starting glacial isostatic adjustment (GIA)-corrected ice-free hypsometry that conserve mean elevation provide a basis for understanding how these compensating changes impact global hypsometry and particularly estimates of global mean shoreline height. Paleo-shoreline height and areal extent of flooding can be defined as the height and corresponding cumulative area of the solid surface of the Earth at which the integral of area as a function of elevation, from the maximum depth upwards, equals the volume of ocean water filling it with respect to cumulative paleo-hypsometry. Present height of the paleo-shoreline is the height on the GIA-corrected cumulative hypsometry at an area equal to the areal extent of flooding. Paleogeographic estimates of global extent of ocean flooding from the Middle Jurassic to end Eocene, when combined with conservation of mean elevation and ocean water volume allow an explicit estimate of the paleo-height and present height of the paleo-shoreline. The best-fitting estimate of present height of the paleo-shoreline, equivalent to a long-term "eustatic" sea level curve, implies very modest (25±22m) changes in long-term sea level above the ice-free sea level height of +40m. These, in turn, imply quite limited changes in mean depth of the oceanic crust (15±11m), and mean age of the oceanic lithosphere ( 62.1±2.4 my) since the Middle Jurassic.

A comparative cost analysis of robot-assisted versus traditional laparoscopic partial nephrectomy.

PubMed

Hyams, Elias; Pierorazio, Philip; Mullins, Jeffrey K; Ward, Maryann; Allaf, Mohamad

2012-07-01

Robot-assisted laparoscopic partial nephrectomy (RALPN) is supplanting traditional laparoscopic partial nephrectomy (LPN) as the technique of choice for minimally invasive nephron-sparing surgery. This evolution has resulted from potential clinical benefits, as well as proliferation of robotic systems and patient demand for robot-assisted surgery. We sought to quantify the costs associated with the use of robotics for minimally invasive partial nephrectomy. A cost analysis was performed for 20 consecutive robot-assisted partial nephrectomy (RPN) and LPN patients at our institution from 2009 to 2010. Data included actual perioperative and hospitalization costs as well as professional fees. Capital costs were estimated using purchase costs and amortization of two robotic systems from 2001 to 2009, as well as maintenance contract costs. The estimated cost/case was obtained using total robotic surgical volume during this period. Total estimated costs were compared between groups. A separate analysis was performed assuming "ideal" robotic utilization during a comparable period. RALPN had a cost premium of +$1066/case compared with LPN, assuming actual robot utilization from 2001 to 2009. Assuming "ideal" utilization during a comparable period, this premium decreased to +$334; capital costs per case decreased from $1907 to $1175. Tumor size, operative time, and length of stay were comparable between groups. RALPN is associated with a small to moderate cost premium depending on assumptions regarding robotic surgical volume. Saturated utilization of robotic systems decreases attributable capital costs and makes comparison with laparoscopy more favorable. Purported clinical benefits of RPN (eg, decreased warm ischemia time, increased utilization of nephron-sparing surgery) need further study, because these may have cost implications.

A cumulative shear mechanism for tissue damage initiation in shock-wave lithotripsy.

PubMed

Freund, Jonathan B; Colonius, Tim; Evan, Andrew P

2007-09-01

Evidence suggests that inertial cavitation plays an important role in the renal injury incurred during shock-wave lithotripsy. However, it is unclear how tissue damage is initiated, and significant injury typically occurs only after a sufficient dose of shock waves. Although it has been suggested that shock-induced shearing might initiate injury, estimates indicate that individual shocks do not produce sufficient shear to do so. In this paper, we hypothesize that the cumulative shear of the many shocks is damaging. This mechanism depends on whether there is sufficient time between shocks for tissue to relax to its unstrained state. We investigate the mechanism with a physics-based simulation model, wherein the basement membranes that define the tubules and vessels in the inner medulla are represented as elastic shells surrounded by viscous fluid. Material properties are estimated from in-vitro tests of renal basement membranes and documented mechanical properties of cells and extracellular gels. Estimates for the net shear deformation from a typical lithotripter shock (approximately 0.1%) are found from a separate dynamic shock simulation. The results suggest that the larger interstitial volume (approximately 40%) near the papilla tip gives the tissue there a relaxation time comparable to clinical shock delivery rates (approximately 1 Hz), thus allowing shear to accumulate. Away from the papilla tip, where the interstitial volume is smaller (approximately 20%), the model tissue relaxes completely before the next shock would be delivered. Implications of the model are that slower delivery rates and broader focal zones should both decrease injury, consistent with some recent observations.

Partial volume correction of brain perfusion estimates using the inherent signal data of time-resolved arterial spin labeling.

PubMed

Ahlgren, André; Wirestam, Ronnie; Petersen, Esben Thade; Ståhlberg, Freddy; Knutsson, Linda

2014-09-01

Quantitative perfusion MRI based on arterial spin labeling (ASL) is hampered by partial volume effects (PVEs), arising due to voxel signal cross-contamination between different compartments. To address this issue, several partial volume correction (PVC) methods have been presented. Most previous methods rely on segmentation of a high-resolution T1 -weighted morphological image volume that is coregistered to the low-resolution ASL data, making the result sensitive to errors in the segmentation and coregistration. In this work, we present a methodology for partial volume estimation and correction, using only low-resolution ASL data acquired with the QUASAR sequence. The methodology consists of a T1 -based segmentation method, with no spatial priors, and a modified PVC method based on linear regression. The presented approach thus avoids prior assumptions about the spatial distribution of brain compartments, while also avoiding coregistration between different image volumes. Simulations based on a digital phantom as well as in vivo measurements in 10 volunteers were used to assess the performance of the proposed segmentation approach. The simulation results indicated that QUASAR data can be used for robust partial volume estimation, and this was confirmed by the in vivo experiments. The proposed PVC method yielded probable perfusion maps, comparable to a reference method based on segmentation of a high-resolution morphological scan. Corrected gray matter (GM) perfusion was 47% higher than uncorrected values, suggesting a significant amount of PVEs in the data. Whereas the reference method failed to completely eliminate the dependence of perfusion estimates on the volume fraction, the novel approach produced GM perfusion values independent of GM volume fraction. The intra-subject coefficient of variation of corrected perfusion values was lowest for the proposed PVC method. As shown in this work, low-resolution partial volume estimation in connection with ASL perfusion estimation is feasible, and provides a promising tool for decoupling perfusion and tissue volume. Copyright © 2014 John Wiley & Sons, Ltd.

Influence of the volume and density functions within geometric models for estimating trunk inertial parameters.

PubMed

Wicke, Jason; Dumas, Genevieve A

2010-02-01

The geometric method combines a volume and a density function to estimate body segment parameters and has the best opportunity for developing the most accurate models. In the trunk, there are many different tissues that greatly differ in density (e.g., bone versus lung). Thus, the density function for the trunk must be particularly sensitive to capture this diversity, such that accurate inertial estimates are possible. Three different models were used to test this hypothesis by estimating trunk inertial parameters of 25 female and 24 male college-aged participants. The outcome of this study indicates that the inertial estimates for the upper and lower trunk are most sensitive to the volume function and not very sensitive to the density function. Although it appears that the uniform density function has a greater influence on inertial estimates in the lower trunk region than in the upper trunk region, this is likely due to the (overestimated) density value used. When geometric models are used to estimate body segment parameters, care must be taken in choosing a model that can accurately estimate segment volumes. Researchers wanting to develop accurate geometric models should focus on the volume function, especially in unique populations (e.g., pregnant or obese individuals).

Breast volume estimation from systematic series of CT scans using the Cavalieri principle and 3D reconstruction.

PubMed

Erić, Mirela; Anderla, Andraš; Stefanović, Darko; Drapšin, Miodrag

2014-01-01

Preoperative breast volume estimation is very important for the success of the breast surgery. In the present study, two different breast volume determination methods, Cavalieri principle and 3D reconstruction were compared. Consecutive sections were taken in slice thickness of 5 mm. Every 2nd breast section in a set of consecutive sections was selected. We marked breast tissue with blue line on each selected section, and so prepared CT scans used for breast volume estimation. The volumes of the 60 breasts were estimated using the Cavalieri principle and 3D reconstruction. The mean breast volume value was established to be 467.79 ± 188.90 cm(3) with Cavalieri method and 465.91 ± 191.41 cm(3) with 3D reconstruction. The mean CE for the estimates in this study was calculated as 0.25%. Skin-sparing volume was about 91.64% of the whole breast volume. Both methods are very accurate and have a strong linear association. Our results suggest that the calculation of breast volume or its part in vivo from systematic series of CT scans using the Cavalieri principle or 3D breast reconstruction is accurate enough to have a significant clinical benefit in planning reconstructive breast surgery. These methods can help the surgeon guide the choice of the most appropriate implant or/and flap preoperatively. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

Two-dimensional echo-cardiographic estimation of left atrial volume and volume load in patients with congenital heart disease.

PubMed

Kawaguchi, A; Linde, L M; Imachi, T; Mizuno, H; Akutsu, H

1983-12-01

To estimate the left atrial volume (LAV) and pulmonary blood flow in patients with congenital heart disease (CHD), we employed two-dimensional echocardiography (TDE). The LAV was measured in dimensions other than those obtained in conventional M-mode echocardiography (M-mode echo). Mathematical and geometrical models for LAV calculation using the standard long-axis, short-axis and apical four-chamber planes were devised and found to be reliable in a preliminary study using porcine heart preparations, although length (10%), area (20%) and volume (38%) were significantly and consistently underestimated with echocardiography. Those models were then applied and correlated with angiocardiograms (ACG) in 25 consecutive patients with suspected CHD. In terms of the estimation of the absolute LAV, accuracy seemed commensurate with the number of the dimensions measured. The correlation between data obtained by TDE and ACG varied with changing hemodynamics such as cardiac cycle, absolute LAV and presence or absence of volume load. The left atrium was found to become spherical and progressively underestimated with TDE at ventricular endsystole, in larger LAV and with increased volume load. Since this tendency became less pronounced in measuring additional dimensions, reliable estimation of the absolute LAV and volume load was possible when 2 or 3 dimensions were measured. Among those calculation models depending on 2 or 3 dimensional measurements, there was only a small difference in terms of accuracy and predictability, although algorithm used varied from one model to another. This suggests that accurate cross-sectional area measurement is critically important for volume estimation rather than any particular algorithm involved. Cross-sectional area measurement by TDE integrated into a three dimensional equivalent allowed a reliable estimate of the LAV or volume load in a variety of hemodynamic situations where M-mode echo was not reliable.

Estimated maximal and current brain volume predict cognitive ability in old age

PubMed Central

Royle, Natalie A.; Booth, Tom; Valdés Hernández, Maria C.; Penke, Lars; Murray, Catherine; Gow, Alan J.; Maniega, Susana Muñoz; Starr, John; Bastin, Mark E.; Deary, Ian J.; Wardlaw, Joanna M.

2013-01-01

Brain tissue deterioration is a significant contributor to lower cognitive ability in later life; however, few studies have appropriate data to establish how much influence prior brain volume and prior cognitive performance have on this association. We investigated the associations between structural brain imaging biomarkers, including an estimate of maximal brain volume, and detailed measures of cognitive ability at age 73 years in a large (N = 620), generally healthy, community-dwelling population. Cognitive ability data were available from age 11 years. We found positive associations (r) between general cognitive ability and estimated brain volume in youth (male, 0.28; females, 0.12), and in measured brain volume in later life (males, 0.27; females, 0.26). Our findings show that cognitive ability in youth is a strong predictor of estimated prior and measured current brain volume in old age but that these effects were the same for both white and gray matter. As 1 of the largest studies of associations between brain volume and cognitive ability with normal aging, this work contributes to the wider understanding of how some early-life factors influence cognitive aging. PMID:23850342

Prediction and error of baldcypress stem volume from stump diameter

Treesearch

Bernard R. Parresol

1998-01-01

The need to estimate the volume of removals occurs for many reasons, such as in trespass cases, severance tax reports, and post-harvest assessments. A logarithmic model is presented for prediction of baldcypress total stem cubic foot volume using stump diameter as the independent variable. Because the error of prediction is as important as the volume estimate, the...

Taper-based system for estimating stem volumes of upland oaks

Treesearch

Donald E. Hilt

1980-01-01

A taper-based system for estimating stem volumes is developed for Central States upland oaks. Inside bark diameters up the stem are predicted as a function of dbhib, total height, and powers and relative height. A Fortran IV computer program, OAKVOL, is used to predict cubic and board-foot volumes to any desired merchantable top dib. Volumes of...

In vivo estimation of normal amygdala volume from structural MRI scans with anatomical-based segmentation.

PubMed

Siozopoulos, Achilleas; Thomaidis, Vasilios; Prassopoulos, Panos; Fiska, Aliki

2018-02-01

Literature includes a number of studies using structural MRI (sMRI) to determine the volume of the amygdala, which is modified in various pathologic conditions. The reported values vary widely mainly because of different anatomical approaches to the complex. This study aims at estimating of the normal amygdala volume from sMRI scans using a recent anatomical definition described in a study based on post-mortem material. The amygdala volume has been calculated in 106 healthy subjects, using sMRI and anatomical-based segmentation. The resulting volumes have been analyzed for differences related to hemisphere, sex, and age. The mean amygdalar volume was estimated at 1.42 cm 3 . The mean right amygdala volume has been found larger than the left, but the difference for the raw values was within the limits of the method error. No intersexual differences or age-related alterations have been observed. The study provides a method for determining the boundaries of the amygdala in sMRI scans based on recent anatomical considerations and an estimation of the mean normal amygdala volume from a quite large number of scans for future use in comparative studies.

Optimal back-extrapolation method for estimating plasma volume in humans using the indocyanine green dilution method.

PubMed

Polidori, David; Rowley, Clarence

2014-07-22

The indocyanine green dilution method is one of the methods available to estimate plasma volume, although some researchers have questioned the accuracy of this method. We developed a new, physiologically based mathematical model of indocyanine green kinetics that more accurately represents indocyanine green kinetics during the first few minutes postinjection than what is assumed when using the traditional mono-exponential back-extrapolation method. The mathematical model is used to develop an optimal back-extrapolation method for estimating plasma volume based on simulated indocyanine green kinetics obtained from the physiological model. Results from a clinical study using the indocyanine green dilution method in 36 subjects with type 2 diabetes indicate that the estimated plasma volumes are considerably lower when using the traditional back-extrapolation method than when using the proposed back-extrapolation method (mean (standard deviation) plasma volume = 26.8 (5.4) mL/kg for the traditional method vs 35.1 (7.0) mL/kg for the proposed method). The results obtained using the proposed method are more consistent with previously reported plasma volume values. Based on the more physiological representation of indocyanine green kinetics and greater consistency with previously reported plasma volume values, the new back-extrapolation method is proposed for use when estimating plasma volume using the indocyanine green dilution method.

Concept for a Satellite-Based Advanced Air Traffic Management System : Volume 7. System Cost.

DOT National Transportation Integrated Search

1973-02-01

The volume presents estimates of the federal government and user costs for the Satellite-Based Advanced Air Traffic Management System and the supporting rationale. The system configuration is that presented in volumes II and III. The cost estimates a...

Validation of equations for pleural effusion volume estimation by ultrasonography.

PubMed

Hassan, Maged; Rizk, Rana; Essam, Hatem; Abouelnour, Ahmed

2017-12-01

To validate the accuracy of previously published equations that estimate pleural effusion volume using ultrasonography. Only equations using simple measurements were tested. Three measurements were taken at the posterior axillary line for each case with effusion: lateral height of effusion ( H ), distance between collapsed lung and chest wall ( C ) and distance between lung and diaphragm ( D ). Cases whose effusion was aspirated to dryness were included and drained volume was recorded. Intra-class correlation coefficient (ICC) was used to determine the predictive accuracy of five equations against the actual volume of aspirated effusion. 46 cases with effusion were included. The most accurate equation in predicting effusion volume was ( H  +  D ) × 70 (ICC 0.83). The simplest and yet accurate equation was H  × 100 (ICC 0.79). Pleural effusion height measured by ultrasonography gives a reasonable estimate of effusion volume. Incorporating distance between lung base and diaphragm into estimation improves accuracy from 79% with the first method to 83% with the latter.

Traffic Volume and Aggregate Economic Activity: Implications for Taking the Pulse of the U.S. Economy

DOT National Transportation Integrated Search

2016-09-01

What is the incremental relevance of real-time traffic volume data for taking the pulse of the U.S. economy? Although prior research has identified a positive link between traffic volume and economic activity, there is a dearth of evidence on the rel...

SU-E-T-129: Are Knowledge-Based Planning Dose Estimates Valid for Distensible Organs?

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

Lalonde, R; Heron, D; Huq, M

2015-06-15

Purpose: Knowledge-based planning programs have become available to assist treatment planning in radiation therapy. Such programs can be used to generate estimated DVHs and planning constraints for organs at risk (OARs), based upon a model generated from previous plans. These estimates are based upon the planning CT scan. However, for distensible OARs like the bladder and rectum, daily variations in volume may make the dose estimates invalid. The purpose of this study is to determine whether knowledge-based DVH dose estimates may be valid for distensible OARs. Methods: The Varian RapidPlan™ knowledge-based planning module was used to generate OAR dose estimatesmore » and planning objectives for 10 prostate cases previously planned with VMAT, and final plans were calculated for each. Five weekly setup CBCT scans of each patient were then downloaded and contoured (assuming no change in size and shape of the target volume), and rectum and bladder DVHs were recalculated for each scan. Dose volumes were then compared at 75, 60,and 40 Gy for the bladder and rectum between the planning scan and the CBCTs. Results: Plan doses and estimates matched well at all dose points., Volumes of the rectum and bladder varied widely between planning CT and the CBCTs, ranging from 0.46 to 2.42 for the bladder and 0.71 to 2.18 for the rectum, causing relative dose volumes to vary between planning CT and CBCT, but absolute dose volumes were more consistent. The overall ratio of CBCT/plan dose volumes was 1.02 ±0.27 for rectum and 0.98 ±0.20 for bladder in these patients. Conclusion: Knowledge-based planning dose volume estimates for distensible OARs are still valid, in absolute volume terms, between treatment planning scans and CBCT’s taken during daily treatment. Further analysis of the data is being undertaken to determine how differences depend upon rectum and bladder filling state. This work has been supported by Varian Medical Systems.« less

Vestibular schwannomas: Accuracy of tumor volume estimated by ice cream cone formula using thin-sliced MR images

PubMed Central

Ho, Hsing-Hao; Li, Ya-Hui; Lee, Jih-Chin; Wang, Chih-Wei; Yu, Yi-Lin; Hueng, Dueng-Yuan; Hsu, Hsian-He

2018-01-01

Purpose We estimated the volume of vestibular schwannomas by an ice cream cone formula using thin-sliced magnetic resonance images (MRI) and compared the estimation accuracy among different estimating formulas and between different models. Methods The study was approved by a local institutional review board. A total of 100 patients with vestibular schwannomas examined by MRI between January 2011 and November 2015 were enrolled retrospectively. Informed consent was waived. Volumes of vestibular schwannomas were estimated by cuboidal, ellipsoidal, and spherical formulas based on a one-component model, and cuboidal, ellipsoidal, Linskey’s, and ice cream cone formulas based on a two-component model. The estimated volumes were compared to the volumes measured by planimetry. Intraobserver reproducibility and interobserver agreement was tested. Estimation error, including absolute percentage error (APE) and percentage error (PE), was calculated. Statistical analysis included intraclass correlation coefficient (ICC), linear regression analysis, one-way analysis of variance, and paired t-tests with P < 0.05 considered statistically significant. Results Overall tumor size was 4.80 ± 6.8 mL (mean ±standard deviation). All ICCs were no less than 0.992, suggestive of high intraobserver reproducibility and high interobserver agreement. Cuboidal formulas significantly overestimated the tumor volume by a factor of 1.9 to 2.4 (P ≤ 0.001). The one-component ellipsoidal and spherical formulas overestimated the tumor volume with an APE of 20.3% and 29.2%, respectively. The two-component ice cream cone method, and ellipsoidal and Linskey’s formulas significantly reduced the APE to 11.0%, 10.1%, and 12.5%, respectively (all P < 0.001). Conclusion The ice cream cone method and other two-component formulas including the ellipsoidal and Linskey’s formulas allow for estimation of vestibular schwannoma volume more accurately than all one-component formulas. PMID:29438424

Efficient Voronoi volume estimation for DEM simulations of granular materials under confined conditions

PubMed Central

Frenning, Göran

2015-01-01

When the discrete element method (DEM) is used to simulate confined compression of granular materials, the need arises to estimate the void space surrounding each particle with Voronoi polyhedra. This entails recurring Voronoi tessellation with small changes in the geometry, resulting in a considerable computational overhead. To overcome this limitation, we propose a method with the following features:•A local determination of the polyhedron volume is used, which considerably simplifies implementation of the method.•A linear approximation of the polyhedron volume is utilised, with intermittent exact volume calculations when needed.•The method allows highly accurate volume estimates to be obtained at a considerably reduced computational cost. PMID:26150975

Onset of multiple sclerosis before adulthood leads to failure of age-expected brain growth

PubMed Central

Aubert-Broche, Bérengère; Fonov, Vladimir; Narayanan, Sridar; Arnold, Douglas L.; Araujo, David; Fetco, Dumitru; Till, Christine; Sled, John G.; Collins, D. Louis

2014-01-01

Objective: To determine the impact of pediatric-onset multiple sclerosis (MS) on age-expected brain growth. Methods: Whole brain and regional volumes of 36 patients with relapsing-remitting MS onset prior to 18 years of age were segmented in 185 longitudinal MRI scans (2–11 scans per participant, 3-month to 2-year scan intervals). MRI scans of 25 age- and sex-matched healthy normal controls (NC) were also acquired at baseline and 2 years later on the same scanner as the MS group. A total of 874 scans from 339 participants from the NIH-funded MRI study of normal brain development acquired at 2-year intervals were used as an age-expected healthy growth reference. All data were analyzed with an automatic image processing pipeline to estimate the volume of brain and brain substructures. Mixed-effect models were built using age, sex, and group as fixed effects. Results: Significant group and age interactions were found with the adjusted models fitting brain volumes and normalized thalamus volumes (p < 10−4). These findings indicate a failure of age-normative brain growth for the MS group, and an even greater failure of thalamic growth. In patients with MS, T2 lesion volume correlated with a greater reduction in age-expected thalamic volume. To exclude any scanner-related influence on our data, we confirmed no significant interaction of group in the adjusted models between the NC and NIH MRI Study of Normal Brain Development groups. Conclusions: Our results provide evidence that the onset of MS during childhood and adolescence limits age-expected primary brain growth and leads to subsequent brain atrophy, implicating an early onset of the neurodegenerative aspect of MS. PMID:25378667

The area-time-integral technique to estimate convective rain volumes over areas applied to satellite data - A preliminary investigation

NASA Technical Reports Server (NTRS)

Doneaud, Andre A.; Miller, James R., Jr.; Johnson, L. Ronald; Vonder Haar, Thomas H.; Laybe, Patrick

1987-01-01

The use of the area-time-integral (ATI) technique, based only on satellite data, to estimate convective rain volume over a moving target is examined. The technique is based on the correlation between the radar echo area coverage integrated over the lifetime of the storm and the radar estimated rain volume. The processing of the GOES and radar data collected in 1981 is described. The radar and satellite parameters for six convective clusters from storm events occurring on June 12 and July 2, 1981 are analyzed and compared in terms of time steps and cluster lifetimes. Rain volume is calculated by first using the regression analysis to generate the regression equation used to obtain the ATI; the ATI versus rain volume relation is then employed to compute rain volume. The data reveal that the ATI technique using satellite data is applicable to the calculation of rain volume.

Test-retest reliability and longitudinal analysis of automated hippocampal subregion volumes in healthy ageing and Alzheimer's disease populations.

PubMed

Worker, Amanda; Dima, Danai; Combes, Anna; Crum, William R; Streffer, Johannes; Einstein, Steven; Mehta, Mitul A; Barker, Gareth J; C R Williams, Steve; O'daly, Owen

2018-04-01

The hippocampal formation is a complex brain structure that is important in cognitive processes such as memory, mood, reward processing and other executive functions. Histological and neuroimaging studies have implicated the hippocampal region in neuropsychiatric disorders as well as in neurodegenerative diseases. This highly plastic limbic region is made up of several subregions that are believed to have different functional roles. Therefore, there is a growing interest in imaging the subregions of the hippocampal formation rather than modelling the hippocampus as a homogenous structure, driving the development of new automated analysis tools. Consequently, there is a pressing need to understand the stability of the measures derived from these new techniques. In this study, an automated hippocampal subregion segmentation pipeline, released as a developmental version of Freesurfer (v6.0), was applied to T1-weighted magnetic resonance imaging (MRI) scans of 22 healthy older participants, scanned on 3 separate occasions and a separate longitudinal dataset of 40 Alzheimer's disease (AD) patients. Test-retest reliability of hippocampal subregion volumes was assessed using the intra-class correlation coefficient (ICC), percentage volume difference and percentage volume overlap (Dice). Sensitivity of the regional estimates to longitudinal change was estimated using linear mixed effects (LME) modelling. The results show that out of the 24 hippocampal subregions, 20 had ICC scores of 0.9 or higher in both samples; these regions include the molecular layer, granule cell layer of the dentate gyrus, CA1, CA3 and the subiculum (ICC > 0.9), whilst the hippocampal fissure and fimbria had lower ICC scores (0.73-0.88). Furthermore, LME analysis of the independent AD dataset demonstrated sensitivity to group and individual differences in the rate of volume change over time in several hippocampal subregions (CA1, molecular layer, CA3, hippocampal tail, fissure and presubiculum). These results indicate that this automated segmentation method provides a robust method with which to measure hippocampal subregions, and may be useful in tracking disease progression and measuring the effects of pharmacological intervention. © 2018 Wiley Periodicals, Inc.

Well-to-refinery emissions and net-energy analysis of China's crude-oil supply

NASA Astrophysics Data System (ADS)

Masnadi, Mohammad S.; El-Houjeiri, Hassan M.; Schunack, Dominik; Li, Yunpo; Roberts, Samori O.; Przesmitzki, Steven; Brandt, Adam R.; Wang, Michael

2018-03-01

Oil is China's second-largest energy source, so it is essential to understand the country's greenhouse gas emissions from crude-oil production. Chinese crude supply is sourced from numerous major global petroleum producers. Here, we use a per-barrel well-to-refinery life-cycle analysis model with data derived from hundreds of public and commercial sources to model the Chinese crude mix and the upstream carbon intensities and energetic productivity of China's crude supply. We generate a carbon-denominated supply curve representing Chinese crude-oil supply from 146 oilfields in 20 countries. The selected fields are estimated to emit between 1.5 and 46.9 g CO2eq MJ-1 of oil, with volume-weighted average emissions of 8.4 g CO2eq MJ-1. These estimates are higher than some existing databases, illustrating the importance of bottom-up models to support life-cycle analysis databases. This study provides quantitative insight into China's energy policy and the economic and environmental implications of China's oil consumption.

Environmental flows for rivers and economic compensation for irrigators.

PubMed

Sisto, Nicholas P

2009-02-01

Securing flows for environmental purposes from an already fully utilized river is an impossible task--unless users are either coerced into freeing up water, or offered incentives to do so. One sensible strategy for motivating users to liberate volumes is to offer them economic compensation. The right amount for that compensation then becomes a key environmental management issue. This paper analyses a proposal to restore and maintain ecosystems on a stretch of the Río Conchos in northern Mexico, downstream from a large irrigation district that consumes nearly all local flows. We present here estimates of environmental flow requirements for these ecosystems and compute compensation figures for irrigators. These figures are derived from crop-specific irrigation water productivities we statistically estimate from a large set of historical production and irrigation data obtained from the district. This work has general implications for river ecosystem management in water-stressed basins, particularly in terms of the design of fair and effective water sharing mechanisms.

Accurately determining log and bark volumes of saw logs using high-resolution laser scan data

Treesearch

R. Edward Thomas; Neal D. Bennett

2014-01-01

Accurately determining the volume of logs and bark is crucial to estimating the total expected value recovery from a log. Knowing the correct size and volume of a log helps to determine which processing method, if any, should be used on a given log. However, applying volume estimation methods consistently can be difficult. Errors in log measurement and oddly shaped...

Ratios for estimating logging residue in the Pacific Northwest.

Treesearch

James O. Howard

1981-01-01

Ratios are presented for estimating the volume of logging residue for any location in Idaho, Washington, and Oregon. They show cubic-foot volume of logging residue per 1,000 board feet of timber harvested and per acre harvested. Tables show gross and net volumes, with and without bark. The volumes of live and dead and cull residue at the time of harvest are also given...

Thalamic lesions in multiple sclerosis by 7T MRI: Clinical implications and relationship to cortical pathology.

PubMed

Harrison, Daniel M; Oh, Jiwon; Roy, Snehashis; Wood, Emily T; Whetstone, Anna; Seigo, Michaela A; Jones, Craig K; Pham, Dzung; van Zijl, Peter; Reich, Daniel S; Calabresi, Peter A

2015-08-01

Pathology in both cortex and deep gray matter contribute to disability in multiple sclerosis (MS). We used the increased signal-to-noise ratio of 7-tesla (7T) MRI to visualize small lesions within the thalamus and to relate this to clinical information and cortical lesions. We obtained 7T MRI scans on 34 MS cases and 15 healthy volunteers. Thalamic lesion number and volume were related to demographic data, clinical disability measures, and lesions in cortical gray matter. Thalamic lesions were found in 24/34 of MS cases. Two lesion subtypes were noted: discrete, ovoid lesions, and more diffuse lesional areas lining the periventricular surface. The number of thalamic lesions was greater in progressive MS compared to relapsing-remitting (mean ±SD, 10.7 ±0.7 vs. 3.0 ±0.7, respectively, p < 0.001). Thalamic lesion burden (count and volume) correlated with EDSS score and measures of cortical lesion burden, but not with white matter lesion burden or white matter volume. Using 7T MRI allows identification of thalamic lesions in MS, which are associated with disability, progressive disease, and cortical lesions. Thalamic lesion analysis may be a simpler, more rapid estimate of overall gray matter lesion burden in MS. © The Author(s), 2015.

Genetic Mapping of Quantitative Trait Loci Controlling Growth and Wood Quality Traits in Eucalyptus Grandis Using a Maternal Half-Sib Family and Rapd Markers

PubMed Central

Grattapaglia, D.; Bertolucci, FLG.; Penchel, R.; Sederoff, R. R.

1996-01-01

Quantitative trait loci (QTL) mapping of forest productivity traits was performed using an open pollinated half-sib family of Eucalyptus grandis. For volume growth, a sequential QTL mapping approach was applied using bulk segregant analysis (BSA), selective genotyping (SG) and cosegregation analysis (CSA). Despite the low heritability of this trait and the heterogeneous genetic background employed for mapping. BSA detected one putative QTL and SG two out of the three later found by CSA. The three putative QTL for volume growth were found to control 13.7% of the phenotypic variation, corresponding to an estimated 43.7% of the genetic variation. For wood specific gravity five QTL were identified controlling 24.7% of the phenotypic variation corresponding to 49% of the genetic variation. Overlapping QTL for CBH, WSG and percentage dry weight of bark were observed. A significant case of digenic epistasis was found, involving unlinked QTL for volume. Our results demonstrate the applicability of the within half-sib design for QTL mapping in forest trees and indicate the existence of major genes involved in the expression of economically important traits related to forest productivity in Eucalyptus grandis. These findings have important implications for marker-assisted tree breeding. PMID:8913761

Main Trend Extraction Based on Irregular Sampling Estimation and Its Application in Storage Volume of Internet Data Center

PubMed Central

Dou, Chao

2016-01-01

The storage volume of internet data center is one of the classical time series. It is very valuable to predict the storage volume of a data center for the business value. However, the storage volume series from a data center is always “dirty,” which contains the noise, missing data, and outliers, so it is necessary to extract the main trend of storage volume series for the future prediction processing. In this paper, we propose an irregular sampling estimation method to extract the main trend of the time series, in which the Kalman filter is used to remove the “dirty” data; then the cubic spline interpolation and average method are used to reconstruct the main trend. The developed method is applied in the storage volume series of internet data center. The experiment results show that the developed method can estimate the main trend of storage volume series accurately and make great contribution to predict the future volume value. 
 PMID:28090205

Main Trend Extraction Based on Irregular Sampling Estimation and Its Application in Storage Volume of Internet Data Center.

PubMed

Miao, Beibei; Dou, Chao; Jin, Xuebo

2016-01-01

The storage volume of internet data center is one of the classical time series. It is very valuable to predict the storage volume of a data center for the business value. However, the storage volume series from a data center is always "dirty," which contains the noise, missing data, and outliers, so it is necessary to extract the main trend of storage volume series for the future prediction processing. In this paper, we propose an irregular sampling estimation method to extract the main trend of the time series, in which the Kalman filter is used to remove the "dirty" data; then the cubic spline interpolation and average method are used to reconstruct the main trend. The developed method is applied in the storage volume series of internet data center. The experiment results show that the developed method can estimate the main trend of storage volume series accurately and make great contribution to predict the future volume value. 
 .

Determination of the total grain size distribution in a vulcanian eruption column, and its implications to stratospheric aerosol perturbation

NASA Technical Reports Server (NTRS)

Murrow, P. J.; Rose, W. I., Jr.; Self, S.

1980-01-01

The total grain distribution of tephra from the eruption by the Fuego volcano in Guatemala on Oct. 14, 1974 was determined by grain size analysis. The region within each isopach has a grain distribution which was weighted proportionally to its percentage volume; the total distribution had a median grain size of 0.6 mm and a sorting coefficient of 2.3. The ash composed of fine particles did not fall in the volcano area as part of the recognizable tephra blanket; the eruption column reached well into the stratosphere to the height of 10-12 km above sea level, with mass flux rate estimated altitudes of 18-23 km

Pericardial adipose tissue and the metabolic syndrome is increased in patients with chronic major depressive disorder compared to acute depression and controls.

PubMed

Kahl, K G; Herrmann, J; Stubbs, B; Krüger, T H C; Cordes, J; Deuschle, M; Schweiger, U; Hüper, K; Helm, S; Birkenstock, A; Hartung, D

2017-01-04

Major depressive disorder (MDD) is associated with an estimated fourfold risk for premature death, largely attributed to cardiovascular disorders. Pericardial adipose tissue (PAT), a fat compartment surrounding the heart, has been implicated in the development of coronary artery disease. An unanswered question is whether people with chronic MDD are more likely to have elevated PAT volumes versus acute MDD and controls (CTRL). The study group consists of sixteen patients with chronic MDD, thirty-four patients with acute MDD, and twenty-five CTRL. PAT and adrenal gland volume were measured by magnetic resonance tomography. Additional measures comprised factors of the metabolic syndrome, cortisol, relative insulin resistance, and pro-inflammatory cytokines (interleukin-6; IL-6 and tumor necrosis factor-α, TNF-α). PAT volumes were significantly increased in patients with chronic MDD>patients with acute MDD>CTRL. Adrenal gland volume was slightly enlarged in patients with chronic MDD>acute MDD>CTRL, although this difference failed to reach significance. The PAT volume was correlated with adrenal gland volume, and cortisol concentrations were correlated with depression severity, measured by BDI-2 and MADRS. Group differences were found concerning the rate of the metabolic syndrome, being most frequent in chronic MDD>acute MDD>CTRL. Further findings comprised increased fasting cortisol, increased TNF-α concentration, and decreased physical activity level in MDD compared to CTRL. Our results extend the existing literature in demonstrating that patients with chronic MDD have the highest risk for developing cardiovascular disorders, indicated by the highest PAT volume and prevalence of metabolic syndrome. The correlation of PAT with adrenal gland volume underscores the role of the hypothalamus-pituitary-adrenal system as mediator for body-composition changes. Metabolic monitoring, health advices and motivation for the improvement of physical fitness may be recommended in depressed patients, in particular in chronic depression. Copyright © 2016 Elsevier Inc. All rights reserved.

FAQ-HDSC/OWP

Science.gov Websites

improve transition, they will be different from the ones published on the PFDS around volumes' boundaries . 2.7 Why do I see inconsistencies in some NOAA Atlas 14 estimates at boundaries of different NOAA Atlas different times in volumes based on state boundaries, some differences in estimates between volumes at

Program Manual for Producing Weight Scaling Conversion Tables

Treesearch

Gary L. Tyre; Clyde A. Fasick; Frank M. Riley; Frank O. Lege

1973-01-01

Three computer programs are presented which can be applied by individual firms to establish a weight-scaling information system, The first generates volume estimates from truckload weights for any combination of veneer, sawmill, and pulpwood volumes. The second provides quality-control information by tabulating differences between estimated volumes and observed check-...

Estimating the Volumes of Solid Figures with Curved Surfaces.

ERIC Educational Resources Information Center

Cohen, Donald

1991-01-01

Several examples of solid figures that calculus students can use to exercise their skills at estimating volume are presented. Although these figures are bounded by surfaces that are portions of regular cylinders, it is interesting to note that their volumes can be expressed as rational numbers. (JJK)

Reserve growth of the world's giant oil fields

USGS Publications Warehouse

Klett, T.R.; Schmoker, J.W.

2005-01-01

Analysis of estimated total recoverable oil volume (field size) of 186 well-known giant oil fields of the world (>0.5 billion bbl of oil, discovered prior to 1981), exclusive of the United States and Canada, demonstrates general increases in field sizes through time. Field sizes were analyzed as a group and within subgroups of the Organization of Petroleum Exporting Countries (OPEC) and non-OPEC countries. From 1981 through 1996, the estimated volume of oil in the 186 fields for which adequate data were available increased from 617 billion to 777 billion bbl of oil (26%). Processes other than new field discoveries added an estimated 160 billion bbl of oil to known reserves in this subset of the world's oil fields. Although methods for estimating field sizes vary among countries, estimated sizes of the giant oil fields of the world increased, probably for many of the same reasons that estimated sizes of oil fields in the United States increased over the same time period. Estimated volumes in OPEC fields increased from a total of 550 billion to 668 billion bbl of oil and volumes in non-OPEC fields increased from 67 billion to 109 billion bbl of oil. In terms of percent change, non-OPEC field sizes increased more than OPEC field sizes (63% versus 22%). The changes in estimated total recoverable oil volumes that occurred within three 5-year increments between 1981 and 1996 were all positive. Between 1981 and 1986, the increase in estimated total recoverable oil volume within the 186 giant oil fields was 11 billion bbl of oil; between 1986 and 1991, the increase was 120 billion bbl of oil; and between 1991 and 1996, the increase was 29 billion bbl of oil. Fields in both OPEC and non-OPEC countries followed trends of substantial reserve growth.

Unbiased estimation of the eyeball volume using the Cavalieri principle on computed tomography images.

PubMed

Acer, Niyazi; Sahin, Bunyamin; Ucar, Tolga; Usanmaz, Mustafa

2009-01-01

The size of the eyeball has been the subject of a few studies. None of them used stereological methods to estimate the volume. In the current study, we estimated the volume of eyeball in normal men and women using the stereological methods. Eyeball volume (EV) was estimated using the Cavalieri principle as a combination of point-counting and planimetry techniques. We used computed tomography scans taken from 36 participants (15 men and 21 women) to estimate the EV. The mean (SD) EV values obtained by planimetry method were 7.49 (0.79) and 7.06 (0.85) cm in men and women, respectively. By using point-counting method, the mean (SD) values were 7.48 (0.85) and 7.21 (0.84) cm in men and women, respectively. There was no statistically significant difference between the findings from the 2 methods (P > 0.05). A weak correlation was found between the axial length of eyeball and the EV estimated by point counting and planimetry (P < 0.05, r = 0.494 and r = 0.523, respectively). The findings of the current study using the stereological methods could provide data for the evaluation of normal and pathologic volumes of the eyeball.

Accurate method for preoperative estimation of the right graft volume in adult-to-adult living donor liver transplantation.

PubMed

Khalaf, H; Shoukri, M; Al-Kadhi, Y; Neimatallah, M; Al-Sebayel, M

2007-06-01

Accurate estimation of graft volume is crucial to avoid small-for-size syndrome following adult-to-adult living donor liver transplantation AALDLT). Herein, we combined radiological and mathematical approaches for preoperative assessment of right graft volume. The right graft volume was preoperatively estimated in 31 live donors using two methods: first, the radiological graft volume (RGV) by computed tomography (CT) volumetry and second, a calculated graft volume (CGV) obtained by multiplying the standard liver volume by the percentage of the right graft volume (given by CT). Both methods were compared to the actual graft volume (AGV) measured during surgery. The graft recipient weight ratio (GRWR) was also calculated using all three volumes (RGV, CGV, and AGV). Lin's concordance correlation coefficient (CCC) was used to assess the agreement between AGV and both RGV and CGV. This was repeated using the GRWR measurements. The mean percentage of right graft volume was 62.4% (range, 55%-68%; SD +/- 3.27%). The CCC between AGV and RGV versus CGV was 0.38 and 0.66, respectively. The CCC between GRWR using AGV and RGV versus CGV was 0.63 and 0.88, respectively (P < .05). According to the Landis and Kock benchmark, the CGV correlated better with AGV when compared to RGV. The better correlation became even more apparent when applied to GRWR. In our experience, CGV showed a better correlation with AGV compared with the RGV. Using CGV in conjunction with RGV may be of value for a more accurate estimation of right graft volume for AALDLT.

Age estimation from canine volumes.

PubMed

De Angelis, Danilo; Gaudio, Daniel; Guercini, Nicola; Cipriani, Filippo; Gibelli, Daniele; Caputi, Sergio; Cattaneo, Cristina

2015-08-01

Techniques for estimation of biological age are constantly evolving and are finding daily application in the forensic radiology field in cases concerning the estimation of the chronological age of a corpse in order to reconstruct the biological profile, or of a living subject, for example in cases of immigration of people without identity papers from a civil registry. The deposition of teeth secondary dentine and consequent decrease of pulp chamber in size are well known as aging phenomena, and they have been applied to the forensic context by the development of age estimation procedures, such as Kvaal-Solheim and Cameriere methods. The present study takes into consideration canines pulp chamber volume related to the entire teeth volume, with the aim of proposing new regression formulae for age estimation using 91 cone beam computerized scans and a freeware open-source software, in order to permit affordable reproducibility of volumes calculation.

Magma ocean formation due to giant impacts

NASA Technical Reports Server (NTRS)

Tonks, W. B.; Melosh, H. J.

1993-01-01

The thermal effects of giant impacts are studied by estimating the melt volume generated by the initial shock wave and corresponding magma ocean depths. Additionally, the effects of the planet's initial temperature on the generated melt volume are examined. The shock pressure required to completely melt the material is determined using the Hugoniot curve plotted in pressure-entropy space. Once the melting pressure is known, an impact melting model is used to estimate the radial distance melting occurred from the impact site. The melt region's geometry then determines the associated melt volume. The model is also used to estimate the partial melt volume. Magma ocean depths resulting from both excavated and retained melt are calculated, and the melt fraction not excavated during the formation of the crater is estimated. The fraction of a planet melted by the initial shock wave is also estimated using the model.

Estimation of the sensitive volume for gravitational-wave source populations using weighted Monte Carlo integration

NASA Astrophysics Data System (ADS)

Tiwari, Vaibhav

2018-07-01

The population analysis and estimation of merger rates of compact binaries is one of the important topics in gravitational wave astronomy. The primary ingredient in these analyses is the population-averaged sensitive volume. Typically, sensitive volume, of a given search to a given simulated source population, is estimated by drawing signals from the population model and adding them to the detector data as injections. Subsequently injections, which are simulated gravitational waveforms, are searched for by the search pipelines and their signal-to-noise ratio (SNR) is determined. Sensitive volume is estimated, by using Monte-Carlo (MC) integration, from the total number of injections added to the data, the number of injections that cross a chosen threshold on SNR and the astrophysical volume in which the injections are placed. So far, only fixed population models have been used in the estimation of binary black holes (BBH) merger rates. However, as the scope of population analysis broaden in terms of the methodologies and source properties considered, due to an increase in the number of observed gravitational wave (GW) signals, the procedure will need to be repeated multiple times at a large computational cost. In this letter we address the problem by performing a weighted MC integration. We show how a single set of generic injections can be weighted to estimate the sensitive volume for multiple population models; thereby greatly reducing the computational cost. The weights in this MC integral are the ratios of the output probabilities, determined by the population model and standard cosmology, and the injection probability, determined by the distribution function of the generic injections. Unlike analytical/semi-analytical methods, which usually estimate sensitive volume using single detector sensitivity, the method is accurate within statistical errors, comes at no added cost and requires minimal computational resources.

Pharmacokinetic evidence for improved ophthalmic drug delivery by reduction of instilled volume.

PubMed

Patton, T F

1977-07-01

The bioavailability of topically applied pilocarpine nitrate was studied as a function of instilled volume. As the instilled volume decreased, the fraction of dose absorbed increased. The relationship between fraction absorbed and instilled volume was not direct, but appropriate adjustment of instilled volume and concentration should permit substantial dosage reductions without sacrifice of drug concentration in the eye. The implications of these findings from both a therapeutic and toxicity standpoint are discussed.

Completely automated estimation of prostate volume for 3-D side-fire transrectal ultrasound using shape prior approach

NASA Astrophysics Data System (ADS)

Li, Lu; Narayanan, Ramakrishnan; Miller, Steve; Shen, Feimo; Barqawi, Al B.; Crawford, E. David; Suri, Jasjit S.

2008-02-01

Real-time knowledge of capsule volume of an organ provides a valuable clinical tool for 3D biopsy applications. It is challenging to estimate this capsule volume in real-time due to the presence of speckles, shadow artifacts, partial volume effect and patient motion during image scans, which are all inherent in medical ultrasound imaging. The volumetric ultrasound prostate images are sliced in a rotational manner every three degrees. The automated segmentation method employs a shape model, which is obtained from training data, to delineate the middle slices of volumetric prostate images. Then a "DDC" algorithm is applied to the rest of the images with the initial contour obtained. The volume of prostate is estimated with the segmentation results. Our database consists of 36 prostate volumes which are acquired using a Philips ultrasound machine using a Side-fire transrectal ultrasound (TRUS) probe. We compare our automated method with the semi-automated approach. The mean volumes using the semi-automated and complete automated techniques were 35.16 cc and 34.86 cc, with the error of 7.3% and 7.6% compared to the volume obtained by the human estimated boundary (ideal boundary), respectively. The overall system, which was developed using Microsoft Visual C++, is real-time and accurate.

Higher Education for Everybody? Issues and Implications.

ERIC Educational Resources Information Center

American Council on Education, Washington, DC.

The theme of the 1970 Annual Meeting of the American Council of Education was "Higher Education for Everybody? Issues and Implications." The papers in this volume address themselves to the question of universal higher education and to the implications of this goal on institutional goals and practices as these relate to a student population that…

Space industrialization. Volume 3: World and domestic implications

NASA Technical Reports Server (NTRS)

1978-01-01

The status of worldwide space industralization activities is assessed as well as the benefits to be anticipated from enhanced activities. Methods for stimulating space industralization growth are discussed with emphasis on foreign and international activities, national and world impact assessments, industry/government interfaces, legal implications, institutional implications, economics and capitalization, and implementation issues and recommendations.

Optimal back-extrapolation method for estimating plasma volume in humans using the indocyanine green dilution method

PubMed Central

2014-01-01

Background The indocyanine green dilution method is one of the methods available to estimate plasma volume, although some researchers have questioned the accuracy of this method. Methods We developed a new, physiologically based mathematical model of indocyanine green kinetics that more accurately represents indocyanine green kinetics during the first few minutes postinjection than what is assumed when using the traditional mono-exponential back-extrapolation method. The mathematical model is used to develop an optimal back-extrapolation method for estimating plasma volume based on simulated indocyanine green kinetics obtained from the physiological model. Results Results from a clinical study using the indocyanine green dilution method in 36 subjects with type 2 diabetes indicate that the estimated plasma volumes are considerably lower when using the traditional back-extrapolation method than when using the proposed back-extrapolation method (mean (standard deviation) plasma volume = 26.8 (5.4) mL/kg for the traditional method vs 35.1 (7.0) mL/kg for the proposed method). The results obtained using the proposed method are more consistent with previously reported plasma volume values. Conclusions Based on the more physiological representation of indocyanine green kinetics and greater consistency with previously reported plasma volume values, the new back-extrapolation method is proposed for use when estimating plasma volume using the indocyanine green dilution method. PMID:25052018

Validity of Three-Dimensional Photonic Scanning Technique for Estimating Percent Body Fat.

PubMed

Shitara, K; Kanehisa, H; Fukunaga, T; Yanai, T; Kawakami, Y

2013-01-01

Three-dimensional photonic scanning (3DPS) was recently developed to measure dimensions of a human body surface. The purpose of this study was to explore the validity of body volume measured by 3DPS for estimating the percent body fat (%fat). Design, setting, participants, and measurement: The body volumes were determined by 3DPS in 52 women. The body volume was corrected for residual lung volume. The %fat was estimated from body density and compared with the corresponding reference value determined by the dual-energy x-ray absorptiometry (DXA). No significant difference was found for the mean values of %fat obtained by 3DPS (22.2 ± 7.6%) and DXA (23.5 ± 4.9%). The root mean square error of %fat between 3DPS and reference technique was 6.0%. For each body segment, there was a significant positive correlation between 3DPS- and DXA-values, although the corresponding value for the head was slightly larger in 3DPS than in DXA. Residual lung volume was negatively correlated with the estimated error in %fat. The body volume determined with 3DPS is potentially useful for estimating %fat. A possible strategy for enhancing the measurement accuracy of %fat might be to refine the protocol for preparing the subject's hair prior to scanning and to improve the accuracy in the measurement of residual lung volume.

Estimated maximal and current brain volume predict cognitive ability in old age.

PubMed

Royle, Natalie A; Booth, Tom; Valdés Hernández, Maria C; Penke, Lars; Murray, Catherine; Gow, Alan J; Maniega, Susana Muñoz; Starr, John; Bastin, Mark E; Deary, Ian J; Wardlaw, Joanna M

2013-12-01

Brain tissue deterioration is a significant contributor to lower cognitive ability in later life; however, few studies have appropriate data to establish how much influence prior brain volume and prior cognitive performance have on this association. We investigated the associations between structural brain imaging biomarkers, including an estimate of maximal brain volume, and detailed measures of cognitive ability at age 73 years in a large (N = 620), generally healthy, community-dwelling population. Cognitive ability data were available from age 11 years. We found positive associations (r) between general cognitive ability and estimated brain volume in youth (male, 0.28; females, 0.12), and in measured brain volume in later life (males, 0.27; females, 0.26). Our findings show that cognitive ability in youth is a strong predictor of estimated prior and measured current brain volume in old age but that these effects were the same for both white and gray matter. As 1 of the largest studies of associations between brain volume and cognitive ability with normal aging, this work contributes to the wider understanding of how some early-life factors influence cognitive aging. Copyright © 2013 Elsevier Inc. All rights reserved.

Multi-views Fusion CNN for Left Ventricular Volumes Estimation on Cardiac MR Images.

PubMed

Luo, Gongning; Dong, Suyu; Wang, Kuanquan; Zuo, Wangmeng; Cao, Shaodong; Zhang, Henggui

2017-10-13

Left ventricular (LV) volumes estimation is a critical procedure for cardiac disease diagnosis. The objective of this paper is to address direct LV volumes prediction task. In this paper, we propose a direct volumes prediction method based on the end-to-end deep convolutional neural networks (CNN). We study the end-to-end LV volumes prediction method in items of the data preprocessing, networks structure, and multi-views fusion strategy. The main contributions of this paper are the following aspects. First, we propose a new data preprocessing method on cardiac magnetic resonance (CMR). Second, we propose a new networks structure for end-to-end LV volumes estimation. Third, we explore the representational capacity of different slices, and propose a fusion strategy to improve the prediction accuracy. The evaluation results show that the proposed method outperforms other state-of-the-art LV volumes estimation methods on the open accessible benchmark datasets. The clinical indexes derived from the predicted volumes agree well with the ground truth (EDV: R=0.974, RMSE=9.6ml; ESV: R=0.976, RMSE=7.1ml; EF: R=0.828, RMSE =4.71%). Experimental results prove that the proposed method has high accuracy and efficiency on LV volumes prediction task. The proposed method not only has application potential for cardiac diseases screening for large-scale CMR data, but also can be extended to other medical image research fields.

New insights into differences in brain organization between Neanderthals and anatomically modern humans

PubMed Central

Pearce, Eiluned; Stringer, Chris; Dunbar, R. I. M.

2013-01-01

Previous research has identified morphological differences between the brains of Neanderthals and anatomically modern humans (AMHs). However, studies using endocasts or the cranium itself are limited to investigating external surface features and the overall size and shape of the brain. A complementary approach uses comparative primate data to estimate the size of internal brain areas. Previous attempts to do this have generally assumed that identical total brain volumes imply identical internal organization. Here, we argue that, in the case of Neanderthals and AMHs, differences in the size of the body and visual system imply differences in organization between the same-sized brains of these two taxa. We show that Neanderthals had significantly larger visual systems than contemporary AMHs (indexed by orbital volume) and that when this, along with their greater body mass, is taken into account, Neanderthals have significantly smaller adjusted endocranial capacities than contemporary AMHs. We discuss possible implications of differing brain organization in terms of social cognition, and consider these in the context of differing abilities to cope with fluctuating resources and cultural maintenance. PMID:23486442

Contributions of volumetrics of the hippocampus and thalamus to verbal memory in temporal lobe epilepsy patients.

PubMed

Stewart, Christopher C; Griffith, H Randall; Okonkwo, Ozioma C; Martin, Roy C; Knowlton, Robert K; Richardson, Elizabeth J; Hermann, Bruce P; Seidenberg, Michael

2009-02-01

Recent theories have posited that the hippocampus and thalamus serve distinct, yet related, roles in episodic memory. Whereas the hippocampus has been implicated in long-term memory encoding and storage, the thalamus, as a whole, has been implicated in the selection of items for subsequent encoding and the use of retrieval strategies. However, dissociating the memory impairment that occurs following thalamic injury as distinguished from that following hippocampal injury has proven difficult. This study examined relationships between MRI volumetric measures of the hippocampus and thalamus and their contributions to prose and rote verbal memory functioning in 18 patients with intractable temporal lobe epilepsy (TLE). Results revealed that bilateral hippocampal and thalamic volume independently predicted delayed prose verbal memory functioning. However, bilateral hippocampal, but not thalamic, volume predicted delayed rote verbal memory functioning. Follow-up analyses indicated that bilateral thalamic volume independently predicted immediate prose, but not immediate rote, verbal recall, whereas bilateral hippocampal volume was not associated with any of these immediate memory measures. These findings underscore the cognitive significance of thalamic atrophy in chronic TLE, demonstrating that hippocampal and thalamic volume make quantitatively, and perhaps qualitatively, distinct contributions to episodic memory functioning in TLE patients. They are also consistent with theories proposing that the hippocampus supports long-term memory encoding and storage, whereas the thalamus is implicated in the executive aspects of episodic memory.

36 CFR 223.50 - Periodic payments.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Total contract value is the product of the estimated volume of the sale multiplied by the rates bid by..., estimated remaining unscaled volume or, in a tree measurement sale, the estimated remaining quantities by... Section 223.50 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND...

Volume estimation of small phantoms and rat kidneys using three-dimensional ultrasonography and a position sensor.

PubMed

Strømmen, Kenneth; Stormark, Tor André; Iversen, Bjarne M; Matre, Knut

2004-09-01

To evaluate the accuracy of small volume estimation, both in vivo and in vitro, measurements with a three-dimensional (3D) ultrasound (US) system were carried out. A position sensor was used and the transmitting frequency was 10 MHz. Balloons with known volumes were scanned while rat kidneys were scanned in vivo and in vitro. The Archimedes' principle was used to estimate the true volume. For balloons, the 3D US system gave very good agreement with true volumes in the volume range 0.1 to 10.0 mL (r = 0.999, n = 45, mean difference +/- 2SD = 0.245 +/- 0.370 mL). For rat kidneys in vivo (volume range 0.6 to 2.7 mL) the method was less accurate (r = 0.800, n = 10, mean difference +/- 2SD = -0.288 +/- 0.676 mL). For rat kidneys in vitro (volume range 0.3 to 2.7 mL) the results showed good agreement (r = 0.981, n = 23, mean difference +/- 2SD = 0.039 +/- 0.254 mL). For balloons, kidneys in vivo and in vitro, the mean percentage error was 9.3 +/- 4.8%, -17.1 +/- 17.4%, and 4.6 +/- 11.5%, respectively. This method can estimate the volume of small phantoms and rat kidneys and opens new possibilities for volume measurements of small objects and the study of organ function in small animals. (E-mail ).

Episodic Memory and Regional Atrophy in Frontotemporal Lobar Degeneration

PubMed Central

Söderlund, Hedvig; Black, Sandra E.; Miller, Bruce L.; Freedman, Morris; Levine, Brian

2008-01-01

It has been unclear to what extent memory is affected in frontotemporal lobar degeneration (FTLD). Since patients usually have atrophy in regions implicated in memory function, the frontal and/or temporal lobes, one would expect some memory impairment, and that the degree of atrophy in these regions would be inversely related to memory function. The purposes of this study were 1) to assess episodic memory function in FTLD, and more specifically patients' ability to episodically re-experience an event, and determine its source; 2) to examine whether memory performance is related to quantified regional brain atrophy. FTLD patients (n=18) and healthy comparison subjects (n=14) were assessed with cued recall, recognition, “remember/know” (self-reported re-experiencing) and source recall, at 30 min and 24 hr after encoding. Regional gray matter volumes were assessed with high resolution structural MRI concurrently to testing. Patients performed worse than comparison subjects on all memory measures. Gray matter volume in the left medial temporal lobe was positively correlated with recognition, re-experiencing, and source recall. Gray matter volume in the left posterior temporal lobe correlated significantly with recognition, at 30 min and 24 hr, and with source recall at 30 min. Estimated familiarity at 30 min was positively correlated with gray matter volume in the left inferior parietal lobe. In summary, episodic memory deficits in FTLD may be more common than previously thought, particularly in patients with left medial and posterior temporal atrophy. PMID:17888461

Market projections of cellulose nanomaterial-enabled products-- Part 2: Volume estimates

Treesearch

John Cowie; E.M. (Ted) Bilek; Theodore H. Wegner; Jo Anne Shatkin

2014-01-01

Nanocellulose has enormous potential to provide an important materials platform in numerous product sectors. This study builds on previous work by the same authors in which likely high-volume, low-volume, and novel applications for cellulosic nanomaterials were identified. In particular, this study creates a transparent methodology and estimates the potential annual...

Be the Volume: A Classroom Activity to Visualize Volume Estimation

ERIC Educational Resources Information Center

Mikhaylov, Jessica

2011-01-01

A hands-on activity can help multivariable calculus students visualize surfaces and understand volume estimation. This activity can be extended to include the concepts of Fubini's Theorem and the visualization of the curves resulting from cross-sections of the surface. This activity uses students as pillars and a sheet or tablecloth for the…

A Comparison of Regional and SiteSpecific Volume Estimation Equations

Treesearch

Joe P. McClure; Jana Anderson; Hans T. Schreuder

1987-01-01

Regression equations for volume by region and site class were examined for lobiolly pine. The regressions for the Coastal Plain and Piedmont regions had significantly different slopes. The results shared important practical differences in percentage of confidence intervals containing the true total volume and in percentage of estimates within a specific proportion of...

Advanced transportation system studies technical area 2 (TA-2): Heavy lift launch vehicle development. volume 3; Program Cost estimates

NASA Technical Reports Server (NTRS)

McCurry, J. B.

1995-01-01

The purpose of the TA-2 contract was to provide advanced launch vehicle concept definition and analysis to assist NASA in the identification of future launch vehicle requirements. Contracted analysis activities included vehicle sizing and performance analysis, subsystem concept definition, propulsion subsystem definition (foreign and domestic), ground operations and facilities analysis, and life cycle cost estimation. The basic period of performance of the TA-2 contract was from May 1992 through May 1993. No-cost extensions were exercised on the contract from June 1993 through July 1995. This document is part of the final report for the TA-2 contract. The final report consists of three volumes: Volume 1 is the Executive Summary, Volume 2 is Technical Results, and Volume 3 is Program Cost Estimates. The document-at-hand, Volume 3, provides a work breakdown structure dictionary, user's guide for the parametric life cycle cost estimation tool, and final report developed by ECON, Inc., under subcontract to Lockheed Martin on TA-2 for the analysis of heavy lift launch vehicle concepts.

Unsteady force estimation using a Lagrangian drift-volume approach

NASA Astrophysics Data System (ADS)

McPhaden, Cameron J.; Rival, David E.

2018-04-01

A novel Lagrangian force estimation technique for unsteady fluid flows has been developed, using the concept of a Darwinian drift volume to measure unsteady forces on accelerating bodies. The construct of added mass in viscous flows, calculated from a series of drift volumes, is used to calculate the reaction force on an accelerating circular flat plate, containing highly-separated, vortical flow. The net displacement of fluid contained within the drift volumes is, through Darwin's drift-volume added-mass proposition, equal to the added mass of the plate and provides the reaction force of the fluid on the body. The resultant unsteady force estimates from the proposed technique are shown to align with the measured drag force associated with a rapid acceleration. The critical aspects of understanding unsteady flows, relating to peak and time-resolved forces, often lie within the acceleration phase of the motions, which are well-captured by the drift-volume approach. Therefore, this Lagrangian added-mass estimation technique opens the door to fluid-dynamic analyses in areas that, until now, were inaccessible by conventional means.

Volume error analysis for lung nodules attached to pulmonary vessels in an anthropomorphic thoracic phantom

NASA Astrophysics Data System (ADS)

Kinnard, Lisa M.; Gavrielides, Marios A.; Myers, Kyle J.; Zeng, Rongping; Peregoy, Jennifer; Pritchard, William; Karanian, John W.; Petrick, Nicholas

2008-03-01

High-resolution CT, three-dimensional (3D) methods for nodule volumetry have been introduced, with the hope that such methods will be more accurate and consistent than currently used planar measures of size. However, the error associated with volume estimation methods still needs to be quantified. Volume estimation error is multi-faceted in the sense that it is impacted by characteristics of the patient, the software tool and the CT system. The overall goal of this research is to quantify the various sources of measurement error and, when possible, minimize their effects. In the current study, we estimated nodule volume from ten repeat scans of an anthropomorphic phantom containing two synthetic spherical lung nodules (diameters: 5 and 10 mm; density: -630 HU), using a 16-slice Philips CT with 20, 50, 100 and 200 mAs exposures and 0.8 and 3.0 mm slice thicknesses. True volume was estimated from an average of diameter measurements, made using digital calipers. We report variance and bias results for volume measurements as a function of slice thickness, nodule diameter, and X-ray exposure.

Animal scavenging and scattering and the implications for documenting the deaths of undocumented border crossers in the Sonoran Desert.

PubMed

Beck, Jess; Ostericher, Ian; Sollish, Gregory; De León, Jason

2015-01-01

Since 1998, over 5500 people have died while attempting to cross the U.S.-Mexico border without authorization. These deaths have primarily occurred in the Arizona desert. Despite the high volume of deaths, little experimental work has been conducted on Sonoran Desert taphonomy. In this study, pig carcasses were used as proxies for human remains and placed in different depositional contexts (i.e., direct sunlight and shade) that replicate typical sites of migrant death. Decomposition was documented through daily site visits, motion-sensitive cameras and GIS mapping, while skeletal preservation was investigated through the collection of the remains and subsequent faunal analysis. Our results suggest that vultures and domestic dogs are underappreciated members of the Sonoran scavenging guild and may disperse skeletal remains and migrant possessions over 25 m from the site of death. The impact of scavengers and the desert environment on the decomposition process has significant implications for estimating death rates and identifying human remains along the Arizona/Mexico border. © 2014 American Academy of Forensic Sciences.

The use of a computerized algorithm to determine single cardiac cell volumes.

PubMed

Marino, T A; Cook, L; Cook, P N; Dwyer, S J

1981-04-01

Single cardiac muscles cell volume data have been difficult to obtain, especially because the shape of a cell is quite complex. With the aid of a surface reconstruction method, a cell volume estimation algorithm has been developed that can be used on serial of cells. The cell surface is reconstructed by means of triangular tiles so that the cell is represented as a polyhedron. When this algorithm was tested on computer generated surfaces of a known volume, the difference was less than 1.6%. Serial sections of two phantoms of a known volume were also reconstructed and a comparison of the mathematically derived volumes and the computed volume estimations gave a per cent difference of between 2.8% and 4.1%. Finally cell volumes derived using conventional methods and volumes calculated using the algorithm were compared. The mean atrial muscle cell volume derived using conventional methods was 7752.7 +/- 644.7 micrometers3, while the mean computerized algorithm estimated atrial muscle cell volume was 7110.6 +/- 625.5 micrometers3. For AV bundle cells the mean cell volume obtained by conventional methods was 484.4 +/- 88.8 micrometers3 and the volume derived from the computer algorithm was 506.0 +/- 78.5 micrometers3. The differences between the volumes calculated using conventional methods and the algorithm were not significantly different.

Infrasound Waveform Inversion and Mass Flux Validation from Sakurajima Volcano, Japan

NASA Astrophysics Data System (ADS)

Fee, D.; Kim, K.; Yokoo, A.; Izbekov, P. E.; Lopez, T. M.; Prata, F.; Ahonen, P.; Kazahaya, R.; Nakamichi, H.; Iguchi, M.

2015-12-01

Recent advances in numerical wave propagation modeling and station coverage have permitted robust inversion of infrasound data from volcanic explosions. Complex topography and crater morphology have been shown to substantially affect the infrasound waveform, suggesting that homogeneous acoustic propagation assumptions are invalid. Infrasound waveform inversion provides an exciting tool to accurately characterize emission volume and mass flux from both volcanic and non-volcanic explosions. Mass flux, arguably the most sought-after parameter from a volcanic eruption, can be determined from the volume flux using infrasound waveform inversion if the volcanic flow is well-characterized. Thus far, infrasound-based volume and mass flux estimates have yet to be validated. In February 2015 we deployed six infrasound stations around the explosive Sakurajima Volcano, Japan for 8 days. Here we present our full waveform inversion method and volume and mass flux estimates of numerous high amplitude explosions using a high resolution DEM and 3-D Finite Difference Time Domain modeling. Application of this technique to volcanic eruptions may produce realistic estimates of mass flux and plume height necessary for volcanic hazard mitigation. Several ground-based instruments and methods are used to independently determine the volume, composition, and mass flux of individual volcanic explosions. Specifically, we use ground-based ash sampling, multispectral infrared imagery, UV spectrometry, and multigas data to estimate the plume composition and flux. Unique tiltmeter data from underground tunnels at Sakurajima also provides a way to estimate the volume and mass of each explosion. In this presentation we compare the volume and mass flux estimates derived from the different methods and discuss sources of error and future improvements.

Estimating load weights with Huber's Cubic Volume formula: a field trial.

Treesearch

Dale R. Waddell

1989-01-01

Log weights were estimated from the product of Huber's cubic volume formula and green density. Tags showing estimated log weights were attached to logs in the field, and the weights were tallied into a single load weight as logs were assembled for aerial yarding. Accuracy of the estimated load weights was evaluated by comparing the predicted with the actual load...

Post-stratified estimation of forest area and growing stock volume using lidar-based stratifications

Treesearch

Ronald E. McRoberts; Terje Gobakken; Erik Næsset

2012-01-01

National forest inventories report estimates of parameters related to forest area and growing stock volume for geographic areas ranging in size from municipalities to entire countries. Landsat imagery has been shown to be a source of auxiliary information that can be used with stratified estimation to increase the precision of estimates, although the increase is...

Validation of Body Volume Acquisition by Using Elliptical Zone Method.

PubMed

Chiu, C-Y; Pease, D L; Fawkner, S; Sanders, R H

2016-12-01

The elliptical zone method (E-Zone) can be used to obtain reliable body volume data including total body volume and segmental volumes with inexpensive and portable equipment. The purpose of this research was to assess the accuracy of body volume data obtained from E-Zone by comparing them with those acquired from the 3D photonic scanning method (3DPS). 17 male participants with diverse somatotypes were recruited. Each participant was scanned twice on the same day by a 3D whole-body scanner and photographed twice for the E-Zone analysis. The body volume data acquired from 3DPS was regarded as the reference against which the accuracy of the E-Zone was assessed. The relative technical error of measurement (TEM) of total body volume estimations was around 3% for E-Zone. E-Zone can estimate the segmental volumes of upper torso, lower torso, thigh, shank, upper arm and lower arm accurately (relative TEM<10%) but the accuracy for small segments including the neck, hand and foot were poor. In summary, E-Zone provides a reliable, inexpensive, portable, and simple method to obtain reasonable estimates of total body volume and to indicate segmental volume distribution. © Georg Thieme Verlag KG Stuttgart · New York.

Correlation between differential renal function estimation using CT-based functional renal parenchymal volume and (99m)Tc - DTPA renal scan.

PubMed

Sarma, Debanga; Barua, Sasanka K; Rajeev, T P; Baruah, Saumar J

2012-10-01

Nuclear renal scan is currently the gold standard imaging study to determine differential renal function. We propose helical CT as single modality for both the anatomical and functional evaluation of kidney with impaired function. In the present study renal parenchymal volume is measured and percent total renal volume is used as a surrogate marker for differential renal function. The objective of this study is to correlate between differential renal function estimation using CT-based renal parenchymal volume measurement with differential renal function estimation using (99m)TC - DTPA renal scan. Twenty-one patients with unilateral obstructive uropathy were enrolled in this prospective comparative study. They were subjected to (99m)Tc - DTPA renal scan and 64 slice helical CT scan which estimates the renal volume depending on the reconstruction of arterial phase images followed by volume rendering and percent renal volume was calculated. Percent renal volume was correlated with percent renal function, as determined by nuclear renal scan using Pearson coefficient. RESULTS AND OBSERVATION: A strong correlation is observed between percent renal volume and percent renal function in obstructed units (r = 0.828, P < 0.001) as well as in nonobstructed units (r = 0.827, P < 0.001). There is a strong correlation between percent renal volume determined by CT scan and percent renal function determined by (99m)TC - DTPA renal scan both in obstructed and in normal units. CT-based percent renal volume can be used as a single radiological tests for both functional and anatomical assessment of impaired renal units.

Accuracy of predicted haemoglobin concentration on cardiopulmonary bypass in paediatric cardiac surgery: effect of different formulae for estimating patient blood volume.

PubMed

Redlin, Matthias; Boettcher, Wolfgang; Dehmel, Frank; Cho, Mi-Young; Kukucka, Marian; Habazettl, Helmut

2017-11-01

When applying a blood-conserving approach in paediatric cardiac surgery with the aim of reducing the transfusion of homologous blood products, the decision to use blood or blood-free priming of the cardiopulmonary bypass (CPB) circuit is often based on the predicted haemoglobin concentration (Hb) as derived from the pre-CPB Hb, the prime volume and the estimated blood volume. We assessed the accuracy of this approach and whether it may be improved by using more sophisticated methods of estimating the blood volume. Data from 522 paediatric cardiac surgery patients treated with CPB with blood-free priming in a 2-year period from May 2013 to May 2015 were collected. Inclusion criteria were body weight <15 kg and available Hb data immediately prior to and after the onset of CPB. The Hb on CPB was predicted according to Fick's principle from the pre-CPB Hb, the prime volume and the patient blood volume. Linear regression analyses and Bland-Altman plots were used to assess the accuracy of the Hb prediction. Different methods to estimate the blood volume were assessed and compared. The initial Hb on CPB correlated well with the predicted Hb (R 2 =0.87, p<0.001). A Bland-Altman plot revealed little bias at 0.07 g/dL and an area of agreement from -1.35 to 1.48 g/dL. More sophisticated methods of estimating blood volume from lean body mass did not improve the Hb prediction, but rather increased bias. Hb prediction is reasonably accurate, with the best result obtained with the simplest method of estimating the blood volume at 80 mL/kg body weight. When deciding for or against blood-free priming, caution is necessary when the predicted Hb lies in a range of ± 2 g/dL around the transfusion trigger.

Gastropod shell size and architecture influence the applicability of methods used to estimate internal volume.

PubMed

Ragagnin, Marilia Nagata; Gorman, Daniel; McCarthy, Ian Donald; Sant'Anna, Bruno Sampaio; de Castro, Cláudio Campi; Turra, Alexander

2018-01-11

Obtaining accurate and reproducible estimates of internal shell volume is a vital requirement for studies into the ecology of a range of shell-occupying organisms, including hermit crabs. Shell internal volume is usually estimated by filling the shell cavity with water or sand, however, there has been no systematic assessment of the reliability of these methods and moreover no comparison with modern alternatives, e.g., computed tomography (CT). This study undertakes the first assessment of the measurement reproducibility of three contrasting approaches across a spectrum of shell architectures and sizes. While our results suggested a certain level of variability inherent for all methods, we conclude that a single measure using sand/water is likely to be sufficient for the majority of studies. However, care must be taken as precision may decline with increasing shell size and structural complexity. CT provided less variation between repeat measures but volume estimates were consistently lower compared to sand/water and will need methodological improvements before it can be used as an alternative. CT indicated volume may be also underestimated using sand/water due to the presence of air spaces visible in filled shells scanned by CT. Lastly, we encourage authors to clearly describe how volume estimates were obtained.

Deorientation of PolSAR coherency matrix for volume scattering retrieval

NASA Astrophysics Data System (ADS)

Kumar, Shashi; Garg, R. D.; Kushwaha, S. P. S.

2016-05-01

Polarimetric SAR data has proven its potential to extract scattering information for different features appearing in single resolution cell. Several decomposition modelling approaches have been developed to retrieve scattering information from PolSAR data. During scattering power decomposition based on physical scattering models it becomes very difficult to distinguish volume scattering as a result from randomly oriented vegetation from scattering nature of oblique structures which are responsible for double-bounce and volume scattering , because both are decomposed in same scattering mechanism. The polarization orientation angle (POA) of an electromagnetic wave is one of the most important character which gets changed due to scattering from geometrical structure of topographic slopes, oriented urban area and randomly oriented features like vegetation cover. The shift in POA affects the polarimetric radar signatures. So, for accurate estimation of scattering nature of feature compensation in polarization orientation shift becomes an essential procedure. The prime objective of this work was to investigate the effect of shift in POA in scattering information retrieval and to explore the effect of deorientation on regression between field-estimated aboveground biomass (AGB) and volume scattering. For this study Dudhwa National Park, U.P., India was selected as study area and fully polarimetric ALOS PALSAR data was used to retrieve scattering information from the forest area of Dudhwa National Park. Field data for DBH and tree height was collect for AGB estimation using stratified random sampling. AGB was estimated for 170 plots for different locations of the forest area. Yamaguchi four component decomposition modelling approach was utilized to retrieve surface, double-bounce, helix and volume scattering information. Shift in polarization orientation angle was estimated and deorientation of coherency matrix for compensation of POA shift was performed. Effect of deorientation on RGB color composite for the forest area can be easily seen. Overestimation of volume scattering and under estimation of double bounce scattering was recorded for PolSAR decomposition without deorientation and increase in double bounce scattering and decrease in volume scattering was noticed after deorientation. This study was mainly focused on volume scattering retrieval and its relation with field estimated AGB. Change in volume scattering after POA compensation of PolSAR data was recorded and a comparison was performed on volume scattering values for all the 170 forest plots for which field data were collected. Decrease in volume scattering after deorientation was noted for all the plots. Regression between PolSAR decomposition based volume scattering and AGB was performed. Before deorientation, coefficient determination (R2) between volume scattering and AGB was 0.225. After deorientation an improvement in coefficient of determination was found and the obtained value was 0.613. This study recommends deorientation of PolSAR data for decomposition modelling to retrieve reliable volume scattering information from forest area.

Complexity of Work-Life Identities and Policy Development: Implications for Work-Life in Higher Education

ERIC Educational Resources Information Center

Lester, Jaime

2016-01-01

This chapter describes the themes that emerged in this volume with attention to important policy implications on the federal, state, and institutional levels. Recommendations for future research are provided.

A simple method to estimate restoration volume as a possible predictor for tooth fracture.

PubMed

Sturdevant, J R; Bader, J D; Shugars, D A; Steet, T C

2003-08-01

Many dentists cite the fracture risk posed by a large existing restoration as a primary reason for their decision to place a full-coverage restoration. However, there is poor agreement among dentists as to when restoration placement is necessary because of the inability to make objective measurements of restoration size. The purpose of this study was to compare a new method to estimate restoration volumes in posterior teeth with analytically determined volumes. True restoration volume proportion (RVP) was determined for 96 melamine typodont teeth: 24 each of maxillary second premolar, mandibular second premolar, maxillary first molar, and mandibular first molar. Each group of 24 was subdivided into 3 groups to receive an O, MO, or MOD amalgam preparation design. Each preparation design was further subdivided into 4 groups of increasingly larger size. The density of amalgam used was calculated according to ANSI/ADA Specification 1. The teeth were weighed before and after restoration with amalgam. Restoration weight was calculated, and the density of amalgam was used to calculate restoration volume. A liquid pycnometer was used to calculate coronal volume after sectioning the anatomic crown from the root horizontally at the cementoenamel junction. True RVP was calculated by dividing restoration volume by coronal volume. An occlusal photograph and a bitewing radiograph were made of each restored tooth to provide 2 perpendicular views. Each image was digitized, and software was used to measure the percentage of the anatomic crown restored with amalgam. Estimated RVP was calculated by multiplying the percentage of the anatomic crown restored from the 2 views together. Pearson correlation coefficients were used to compare estimated RVP with true RVP. The Pearson correlation coefficient of true RVP with estimated RVP was 0.97 overall (P

Dose-volume histogram prediction using density estimation.

PubMed

Skarpman Munter, Johanna; Sjölund, Jens

2015-09-07

Knowledge of what dose-volume histograms can be expected for a previously unseen patient could increase consistency and quality in radiotherapy treatment planning. We propose a machine learning method that uses previous treatment plans to predict such dose-volume histograms. The key to the approach is the framing of dose-volume histograms in a probabilistic setting.The training consists of estimating, from the patients in the training set, the joint probability distribution of some predictive features and the dose. The joint distribution immediately provides an estimate of the conditional probability of the dose given the values of the predictive features. The prediction consists of estimating, from the new patient, the distribution of the predictive features and marginalizing the conditional probability from the training over this. Integrating the resulting probability distribution for the dose yields an estimate of the dose-volume histogram.To illustrate how the proposed method relates to previously proposed methods, we use the signed distance to the target boundary as a single predictive feature. As a proof-of-concept, we predicted dose-volume histograms for the brainstems of 22 acoustic schwannoma patients treated with stereotactic radiosurgery, and for the lungs of 9 lung cancer patients treated with stereotactic body radiation therapy. Comparing with two previous attempts at dose-volume histogram prediction we find that, given the same input data, the predictions are similar.In summary, we propose a method for dose-volume histogram prediction that exploits the intrinsic probabilistic properties of dose-volume histograms. We argue that the proposed method makes up for some deficiencies in previously proposed methods, thereby potentially increasing ease of use, flexibility and ability to perform well with small amounts of training data.

Vector velocity volume flow estimation: Sources of error and corrections applied for arteriovenous fistulas.

PubMed

Jensen, Jonas; Olesen, Jacob Bjerring; Stuart, Matthias Bo; Hansen, Peter Møller; Nielsen, Michael Bachmann; Jensen, Jørgen Arendt

2016-08-01

A method for vector velocity volume flow estimation is presented, along with an investigation of its sources of error and correction of actual volume flow measurements. Volume flow errors are quantified theoretically by numerical modeling, through flow phantom measurements, and studied in vivo. This paper investigates errors from estimating volumetric flow using a commercial ultrasound scanner and the common assumptions made in the literature. The theoretical model shows, e.g. that volume flow is underestimated by 15%, when the scan plane is off-axis with the vessel center by 28% of the vessel radius. The error sources were also studied in vivo under realistic clinical conditions, and the theoretical results were applied for correcting the volume flow errors. Twenty dialysis patients with arteriovenous fistulas were scanned to obtain vector flow maps of fistulas. When fitting an ellipsis to cross-sectional scans of the fistulas, the major axis was on average 10.2mm, which is 8.6% larger than the minor axis. The ultrasound beam was on average 1.5mm from the vessel center, corresponding to 28% of the semi-major axis in an average fistula. Estimating volume flow with an elliptical, rather than circular, vessel area and correcting the ultrasound beam for being off-axis, gave a significant (p=0.008) reduction in error from 31.2% to 24.3%. The error is relative to the Ultrasound Dilution Technique, which is considered the gold standard for volume flow estimation for dialysis patients. The study shows the importance of correcting for volume flow errors, which are often made in clinical practice. Copyright © 2016 Elsevier B.V. All rights reserved.

Force estimation from OCT volumes using 3D CNNs.

PubMed

Gessert, Nils; Beringhoff, Jens; Otte, Christoph; Schlaefer, Alexander

2018-07-01

Estimating the interaction forces of instruments and tissue is of interest, particularly to provide haptic feedback during robot-assisted minimally invasive interventions. Different approaches based on external and integrated force sensors have been proposed. These are hampered by friction, sensor size, and sterilizability. We investigate a novel approach to estimate the force vector directly from optical coherence tomography image volumes. We introduce a novel Siamese 3D CNN architecture. The network takes an undeformed reference volume and a deformed sample volume as an input and outputs the three components of the force vector. We employ a deep residual architecture with bottlenecks for increased efficiency. We compare the Siamese approach to methods using difference volumes and two-dimensional projections. Data were generated using a robotic setup to obtain ground-truth force vectors for silicon tissue phantoms as well as porcine tissue. Our method achieves a mean average error of [Formula: see text] when estimating the force vector. Our novel Siamese 3D CNN architecture outperforms single-path methods that achieve a mean average error of [Formula: see text]. Moreover, the use of volume data leads to significantly higher performance compared to processing only surface information which achieves a mean average error of [Formula: see text]. Based on the tissue dataset, our methods shows good generalization in between different subjects. We propose a novel image-based force estimation method using optical coherence tomography. We illustrate that capturing the deformation of subsurface structures substantially improves force estimation. Our approach can provide accurate force estimates in surgical setups when using intraoperative optical coherence tomography.

How large is the typical subarachnoid hemorrhage? A review of current neurosurgical knowledge.

PubMed

Whitmore, Robert G; Grant, Ryan A; LeRoux, Peter; El-Falaki, Omar; Stein, Sherman C

2012-01-01

Despite the morbidity and mortality of subarachnoid hemorrhage (SAH), the average volume of a typical hemorrhage is not well defined. Animal models of SAH often do not accurately mimic the human disease process. The purpose of this study is to estimate the average SAH volume, allowing standardization of animal models of the disease. We performed a MEDLINE search of SAH volume and erythrocyte counts in human cerebrospinal fluid as well as for volumes of blood used in animal injection models of SAH, from 1956 to 2010. We polled members of the American Association of Neurological Surgeons (AANS) for estimates of typical SAH volume. Using quantitative data from the literature, we calculated the total volume of SAH as equal to the volume of blood clotted in basal cisterns plus the volume of dispersed blood in cerebrospinal fluid. The results of the AANS poll confirmed our estimates. The human literature yielded 322 publications and animal literature, 237 studies. Four quantitative human studies reported blood clot volumes ranging from 0.2 to 170 mL, with a mean of ∼20 mL. There was only one quantitative study reporting cerebrospinal fluid red blood cell counts from serial lumbar puncture after SAH. Dispersed blood volume ranged from 2.9 to 45.9 mL, and we used the mean of 15 mL for our calculation. Therefore, total volume of SAH equals 35 mL. The AANS poll yielded 176 responses, ranging from 2 to 350 mL, with a mean of 33.9 ± 4.4 mL. Based on our estimate of total SAH volume of 35 mL, animal injection models may now become standardized for more accurate portrayal of the human disease process. Copyright © 2012 Elsevier Inc. All rights reserved.

Comparison of whole body and tissue blood volumes in rainbow trout (Salmo gairdneri) with 125I bovine serum albumin and 51Cr-erythrocyte tracers

USGS Publications Warehouse

Gingerich, W.H.; Pityer, R.A.

1989-01-01

Total, packed cell and, plasma volume estimates were made for the whole body and selected tissues of rainbow trout by the simultaneous injection of radiolabelled trout erythrocyte (51Cr-RBC) and radioiodinated bovine serum albumin (125I-BSA) tracers. Blood volumes were estimated with both markers separately by the tracer-hematocrit method and as the combination of the 51Cr-RBC packed cell and 125I-BSA plasma volumes. Mean whole body blood volume was significantly less when calculated from the 51Cr-RBC tracer data (3.52±0.78 ml/100 g; ±SD) than when calculated with the 125I-BSA tracer (5.06±0.86 ml/100 g) or as the sum of the two volumes combined (4.49±0.60 ml/100 g). The whole body hematocrit (28±5%), estimated as the quotient of the 51Cr-RBC volume divided by the sum of the 125I-BSA and the 51Cr-RBC volumes, also was significantly less than the dorsal aortic microhematocrit (36±4%). Estimates of total blood volumes in most tissues were significantly smaller when calculated from the51Cr-RBC data than when calculated by the other two methods. Tissue blood volumes were greatest in highly vascularized and well perfused tissues and least in poorly vascularized tissues. The relative degree of vascularization among tissues generally remained the same regardless of whether the red cell or the plasma tracer was used to calculated blood volume. It is not clear whether the expanded plasma volume is the result of the distribution of erythrocyte-poor blood into the secondary circulation or the result of extravascular exchange of plasma proteins.

Lower limb muscle volume estimation from maximum cross-sectional area and muscle length in cerebral palsy and typically developing individuals.

PubMed

Vanmechelen, Inti M; Shortland, Adam P; Noble, Jonathan J

2018-01-01

Deficits in muscle volume may be a significant contributor to physical disability in young people with cerebral palsy. However, 3D measurements of muscle volume using MRI or 3D ultrasound may be difficult to make routinely in the clinic. We wished to establish whether accurate estimates of muscle volume could be made from a combination of anatomical cross-sectional area and length measurements in samples of typically developing young people and young people with bilateral cerebral palsy. Lower limb MRI scans were obtained from the lower limbs of 21 individuals with cerebral palsy (14.7±3years, 17 male) and 23 typically developing individuals (16.8±3.3years, 16 male). The volume, length and anatomical cross-sectional area were estimated from six muscles of the left lower limb. Analysis of Covariance demonstrated that the relationship between the length*cross-sectional area and volume was not significantly different depending on the subject group. Linear regression analysis demonstrated that the product of anatomical cross-sectional area and length bore a strong and significant relationship to the measured muscle volume (R 2 values between 0.955 and 0.988) with low standard error of the estimates of 4.8 to 8.9%. This study demonstrates that muscle volume may be estimated accurately in typically developing individuals and individuals with cerebral palsy by a combination of anatomical cross-sectional area and muscle length. 2D ultrasound may be a convenient method of making these measurements routinely in the clinic. Copyright © 2017 Elsevier Ltd. All rights reserved.

Socialization of prosocial behavior: Gender differences in the mediating role of child brain volume.

PubMed

Kok, Rianne; Prinzie, Peter; Bakermans-Kranenburg, Marian J; Verhulst, Frank C; White, Tonya; Tiemeier, Henning; van IJzendoorn, Marinus H

2018-08-01

Evidence has been accumulating for the impact of normal variation in caregiving quality on brain morphology in children, but the question remains whether differences in brain volume related to early caregiving translate to behavioral implications. In this longitudinal population-based study (N = 162), moderated mediation was tested for the relation between parental sensitivity and child prosocial behavior via brain volume, in boys and girls. Both maternal and paternal sensitivity were repeatedly observed between 1 and 4 years of age. Brain volume was assessed using magnetic resonance imaging measurements at age 8, and self-reported prosocial behavior of children was assessed at 9 years of age. Parental sensitivity was positively related to child brain volume, and to child prosocial behavior at trend level. Child brain volume was negatively related to child prosocial behavior. A significant gender-by-brain interaction was found, illustrating that daughters of sensitive parents were more prosocial and that less prosocial behavior was reported for girls with a larger total brain volume. Child gender significantly moderated the indirect effect of parental sensitivity on prosocial behavior via total brain volume. A significant indirect pathway was found only in girls. The results warrant replication but indicate the importance of considering gender when studying the behavioral implications of differences in brain volume related to early caregiving experiences.

Estimating flood hydrographs and volumes for Alabama streams

USGS Publications Warehouse

Olin, D.A.; Atkins, J.B.

1988-01-01

The hydraulic design of highway drainage structures involves an evaluation of the effect of the proposed highway structures on lives, property, and stream stability. Flood hydrographs and associated flood volumes are useful tools in evaluating these effects. For design purposes, the Alabama Highway Department needs information on flood hydrographs and volumes associated with flood peaks of specific recurrence intervals (design floods) at proposed or existing bridge crossings. This report will provide the engineer with a method to estimate flood hydrographs, volumes, and lagtimes for rural and urban streams in Alabama with drainage areas less than 500 sq mi. Existing computer programs and methods to estimate flood hydrographs and volumes for ungaged streams have been developed in Georgia. These computer programs and methods were applied to streams in Alabama. The report gives detailed instructions on how to estimate flood hydrographs for ungaged rural or urban streams in Alabama with drainage areas less than 500 sq mi, without significant in-channel storage or regulations. (USGS)

Measurement of lung expansion with computed tomography and comparison with quantitative histology.

PubMed

Coxson, H O; Mayo, J R; Behzad, H; Moore, B J; Verburgt, L M; Staples, C A; Paré, P D; Hogg, J C

1995-11-01

The total and regional lung volumes were estimated from computed tomography (CT), and the pleural pressure gradient was determined by using the milliliters of gas per gram of tissue estimated from the X-ray attenuation values and the pressure-volume curve of the lung. The data show that CT accurately estimated the volume of the resected lobe but overestimated its weight by 24 +/- 19%. The volume of gas per gram of tissue was less in the gravity-dependent regions due to a pleural pressure gradient of 0.24 +/- 0.08 cmH2O/cm of descent in the thorax. The proportion of tissue to air obtained with CT was similar to that obtained by quantitative histology. We conclude that the CT scan can be used to estimate total and regional lung volumes and that measurements of the proportions of tissue and air within the thorax by CT can be used in conjunction with quantitative histology to evaluate lung structure.

PREOPERATIVE COMPUTED TOMOGRAPHY VOLUMETRY AND GRAFT WEIGHT ESTIMATION IN ADULT LIVING DONOR LIVER TRANSPLANTATION

PubMed Central

PINHEIRO, Rafael S.; CRUZ-JR, Ruy J.; ANDRAUS, Wellington; DUCATTI, Liliana; MARTINO, Rodrigo B.; NACIF, Lucas S.; ROCHA-SANTOS, Vinicius; ARANTES, Rubens M; LAI, Quirino; IBUKI, Felicia S.; ROCHA, Manoel S.; D´ALBUQUERQUE, Luiz A. C.

2017-01-01

ABSTRACT Background: Computed tomography volumetry (CTV) is a useful tool for predicting graft weights (GW) for living donor liver transplantation (LDLT). Few studies have examined the correlation between CTV and GW in normal liver parenchyma. Aim: To analyze the correlation between CTV and GW in an adult LDLT population and provide a systematic review of the existing mathematical models to calculate partial liver graft weight. Methods: Between January 2009 and January 2013, 28 consecutive donors undergoing right hepatectomy for LDLT were retrospectively reviewed. All grafts were perfused with HTK solution. Estimated graft volume was estimated by CTV and these values were compared to the actual graft weight, which was measured after liver harvesting and perfusion. Results: Median actual GW was 782.5 g, averaged 791.43±136 g and ranged from 520-1185 g. Median estimated graft volume was 927.5 ml, averaged 944.86±200.74 ml and ranged from 600-1477 ml. Linear regression of estimated graft volume and actual GW was significantly linear (GW=0.82 estimated graft volume, r2=0.98, slope=0.47, standard deviation of 0.024 and p<0.0001). Spearman Linear correlation was 0.65 with 95% CI of 0.45 - 0.99 (p<0.0001). Conclusion: The one-to-one rule did not applied in patients with normal liver parenchyma. A better estimation of graft weight could be reached by multiplying estimated graft volume by 0.82. PMID:28489167

Comparison of Past, Present, and Future Volume Estimation Methods for Tennessee

Treesearch

Stanley J. Zarnoch; Alexander Clark; Ray A. Souter

2003-01-01

Forest Inventory and Analysis 1999 survey data for Tennessee were used to compare stem-volume estimates obtained using a previous method, the current method, and newly developed taper models that will be used in the future. Compared to the current method, individual tree volumes were consistently underestimated with the previous method, especially for the hardwoods....

Estimators and characteristics of logging residue in Montana.

Treesearch

James. O Howard; Carl E. Fiedler

1984-01-01

Ratios are presented for estimating volume and characteristics of logging residue in Montana. They relate cubic-foot volume of residue to thousand board feet of timber harvested and to acres harvested. Tables show gross and net volume of residue, with and without bark, by diameter and length classes; by number of pieces per acre; by percent soundness; by product...

Process compressor technology. Volume 2: TI-59 manual for estimating centrifugal compressor performance

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

Lapina, R.P.

1983-01-01

This volume provides the performance-estimating procedures of Volume 1 in the from of calculator programs. Each chapter contains one program and is divided into five parts: the background (which develops the technology and equations); the program description; user instructions; sample problems; and the program listing. More than 25 programs are included.

Southern forest inventory and analysis volume equation user’s guide

Treesearch

Christopher M. Oswalt; Roger C. Conner

2011-01-01

Reliable volume estimation procedures are fundamental to the mission of the Forest Inventory and Analysis (FIA) program. Moreover, public access to FIA program procedures is imperative. Here we present the volume estimation procedures used by the southern FIA program of the U.S. Department of Agriculture Forest Service Southern Research Station. The guide presented...

Timber volume and aboveground live tree biomass estimations for landscape analyses in the Pacific Northwest

Treesearch

Xiaoping Zhou; Miles A. Hemstrom

2010-01-01

Timber availability, aboveground tree biomass, and changes in aboveground carbon pools are important consequences of landscape management. There are several models available for calculating tree volume and aboveground tree biomass pools. This paper documents species-specific regional equations for tree volume and aboveground live tree biomass estimation that might be...

Nebraska's forest resources in 2002.

Treesearch

Katherine P. O' Neill; Earl C. Leatherberry; William R. Lovett

2004-01-01

Results of the 2002 annual inventory of Nebraska show an estimated 1,346.5 thousand acres of forest land in the State. The estimated total volume of all live trees on forest land is 1.9 billion cubic feet. An estimated 1,297.4 thousand acres of forest land are classified as timberland. The estimate of growing-stock volume on timberland is 1.6 billion cubic feet. All...

A test of alternative estimators for volume at time 1 from remeasured point samples

Treesearch

Francis A. Roesch; Edwin J. Green; Charles T. Scott

1993-01-01

Two estimators for volume at time 1 for use with permanent horizontal point samples are evaluated. One estimator, used traditionally, uses only the trees sampled at time 1, while the second estimator, originally presented by Roesch and coauthors (F.A. Roesch, Jr., E.J. Green, and C.T. Scott. 1989. For. Sci. 35(2):281-293). takes advantage of additional sample...

A general method for assessing the effects of uncertainty in individual-tree volume model predictions on large-area volume estimates with a subtropical forest illustration

Treesearch

Ronald E. McRoberts; Paolo Moser; Laio Zimermann Oliveira; Alexander C. Vibrans

2015-01-01

Forest inventory estimates of tree volume for large areas are typically calculated by adding the model predictions of volumes for individual trees at the plot level, calculating the mean over plots, and expressing the result on a per unit area basis. The uncertainty in the model predictions is generally ignored, with the result that the precision of the large-area...

Design of an optimum computer vision-based automatic abalone (Haliotis discus hannai) grading algorithm.

PubMed

Lee, Donggil; Lee, Kyounghoon; Kim, Seonghun; Yang, Yongsu

2015-04-01

An automatic abalone grading algorithm that estimates abalone weights on the basis of computer vision using 2D images is developed and tested. The algorithm overcomes the problems experienced by conventional abalone grading methods that utilize manual sorting and mechanical automatic grading. To design an optimal algorithm, a regression formula and R(2) value were investigated by performing a regression analysis for each of total length, body width, thickness, view area, and actual volume against abalone weights. The R(2) value between the actual volume and abalone weight was 0.999, showing a relatively high correlation. As a result, to easily estimate the actual volumes of abalones based on computer vision, the volumes were calculated under the assumption that abalone shapes are half-oblate ellipsoids, and a regression formula was derived to estimate the volumes of abalones through linear regression analysis between the calculated and actual volumes. The final automatic abalone grading algorithm is designed using the abalone volume estimation regression formula derived from test results, and the actual volumes and abalone weights regression formula. In the range of abalones weighting from 16.51 to 128.01 g, the results of evaluation of the performance of algorithm via cross-validation indicate root mean square and worst-case prediction errors of are 2.8 and ±8 g, respectively. © 2015 Institute of Food Technologists®

Echocardiography underestimates stroke volume and aortic valve area: implications for patients with small-area low-gradient aortic stenosis.

PubMed

Chin, Calvin W L; Khaw, Hwan J; Luo, Elton; Tan, Shuwei; White, Audrey C; Newby, David E; Dweck, Marc R

2014-09-01

Discordance between small aortic valve area (AVA; < 1.0 cm(2)) and low mean pressure gradient (MPG; < 40 mm Hg) affects a third of patients with moderate or severe aortic stenosis (AS). We hypothesized that this is largely due to inaccurate echocardiographic measurements of the left ventricular outflow tract area (LVOTarea) and stroke volume alongside inconsistencies in recommended thresholds. One hundred thirty-three patients with mild to severe AS and 33 control individuals underwent comprehensive echocardiography and cardiovascular magnetic resonance imaging (MRI). Stroke volume and LVOTarea were calculated using echocardiography and MRI, and the effects on AVA estimation were assessed. The relationship between AVA and MPG measurements was then modelled with nonlinear regression and consistent thresholds for these parameters calculated. Finally the effect of these modified AVA measurements and novel thresholds on the number of patients with small-area low-gradient AS was investigated. Compared with MRI, echocardiography underestimated LVOTarea (n = 40; -0.7 cm(2); 95% confidence interval [CI], -2.6 to 1.3), stroke volumes (-6.5 mL/m(2); 95% CI, -28.9 to 16.0) and consequently, AVA (-0.23 cm(2); 95% CI, -1.01 to 0.59). Moreover, an AVA of 1.0 cm(2) corresponded to MPG of 24 mm Hg based on echocardiographic measurements and 37 mm Hg after correction with MRI-derived stroke volumes. Based on conventional measures, 56 patients had discordant small-area low-gradient AS. Using MRI-derived stroke volumes and the revised thresholds, a 48% reduction in discordance was observed (n = 29). Echocardiography underestimated LVOTarea, stroke volume, and therefore AVA, compared with MRI. The thresholds based on current guidelines were also inconsistent. In combination, these factors explain > 40% of patients with discordant small-area low-gradient AS. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Male orthopaedic surgeons and anaesthetists: equally good at estimating fluid volumes (and changing light bulbs) but equally poor at estimating procedure duration.

PubMed

Chua, Weiliang; Kong, Chee Hoe; Murphy, Diarmuid Paul

2015-05-01

How many orthopods does it take to change a light bulb? One - to refer to the medics for 'Darkness ?Cause'. Additionally, anaesthetists and surgeons often disagree on the estimated blood loss during surgery and the estimated procedure duration. We designed this study to compare the ability of orthopaedic surgeons and anaesthetists in: (a) estimating fluid volumes; (b) estimating procedure durations; and (c) changing light bulbs. Participants had to either be a specialist in anaesthesia or orthopaedic surgery, or a trainee in that specialty for at least two years. Three different fluid specimens were used for volume estimation (44 mL, 88 mL and 144 mL). Two videos of different lengths (140 seconds and 170 seconds), showing the suturing of a banana skin, were used for procedure duration estimation. To determine the ability at changing light bulbs, the participants had to match eight different light sockets to their respective bulbs. 30 male anaesthetists and trainees and 31 male orthopaedic surgeons and trainees participated in this study. Orthopaedic surgeons underestimated the three fluid volumes by 3.9% and anaesthetists overestimated by 5.1% (p = 0.925). Anaesthetists and orthopaedic surgeons overestimated the duration of the two procedures by 21.2% and 43.1%, respectively (p = 0.006). Anaesthetists had a faster mean time in changing light bulbs (70.1 seconds vs. 74.1 seconds, p = 0.319). In an experimental environment, male orthopaedic surgeons are as good as male anaesthetists in estimating fluid volumes (in commonly seen surgical specimens) and in changing light bulbs. Both groups are poor at estimating procedure durations.

Prediction of resource volumes at untested locations using simple local prediction models

USGS Publications Warehouse

Attanasi, E.D.; Coburn, T.C.; Freeman, P.A.

2006-01-01

This paper shows how local spatial nonparametric prediction models can be applied to estimate volumes of recoverable gas resources at individual undrilled sites, at multiple sites on a regional scale, and to compute confidence bounds for regional volumes based on the distribution of those estimates. An approach that combines cross-validation, the jackknife, and bootstrap procedures is used to accomplish this task. Simulation experiments show that cross-validation can be applied beneficially to select an appropriate prediction model. The cross-validation procedure worked well for a wide range of different states of nature and levels of information. Jackknife procedures are used to compute individual prediction estimation errors at undrilled locations. The jackknife replicates also are used with a bootstrap resampling procedure to compute confidence bounds for the total volume. The method was applied to data (partitioned into a training set and target set) from the Devonian Antrim Shale continuous-type gas play in the Michigan Basin in Otsego County, Michigan. The analysis showed that the model estimate of total recoverable volumes at prediction sites is within 4 percent of the total observed volume. The model predictions also provide frequency distributions of the cell volumes at the production unit scale. Such distributions are the basis for subsequent economic analyses. ?? Springer Science+Business Media, LLC 2007.

High-volume resistance training session acutely diminishes respiratory muscle strength.

PubMed

Hackett, Daniel A; Johnson, Nathan A; Chow, Chin-Moi

2012-01-01

This study investigated the effect of a high-volume compared to a low-volume resistance training session on maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP). Twenty male subjects with resistance training experience (6.2 ± 3.2 y), in a crossover trial, completed two resistance training protocols (high-volume: 5 sets per exercise; low-volume: 2 sets per exercise) and a control session (no exercise) on 3 separate occasions. MIP and MEP decreased by 13.6% (p < 0.01) and 14.7% (p < 0.01) respectively from pre-session MIP and MEP, following the high-volume session. MIP and MEP were unaffected following the low-volume or the control sessions. MIP returned to pre-session values after 40 minutes, whereas MEP remained significantly reduced after 60 minutes post-session by 9.2% compared to pre-session (p < 0.01). The findings suggest that the high-volume session significantly decreased MIP and MEP post-session, implicating a substantially increased demand on the respiratory muscles and that adequate recovery is mandatory following this mode of training. Key pointsRespiratory muscular strength performance is acutely diminished following a high-volume whole-body resistance training session.Greater ventilatory requirements and generation of IAP during the high-volume resistance training session may have contributed to the increased demand placed on the respiratory muscles.Protracted return of respiratory muscular strength performance to baseline levels may have implications for individuals prior to engaging in subsequent exercise bouts.

A semi-automatic method for left ventricle volume estimate: an in vivo validation study

NASA Technical Reports Server (NTRS)

Corsi, C.; Lamberti, C.; Sarti, A.; Saracino, G.; Shiota, T.; Thomas, J. D.

2001-01-01

This study aims to the validation of the left ventricular (LV) volume estimates obtained by processing volumetric data utilizing a segmentation model based on level set technique. The validation has been performed by comparing real-time volumetric echo data (RT3DE) and magnetic resonance (MRI) data. A validation protocol has been defined. The validation protocol was applied to twenty-four estimates (range 61-467 ml) obtained from normal and pathologic subjects, which underwent both RT3DE and MRI. A statistical analysis was performed on each estimate and on clinical parameters as stroke volume (SV) and ejection fraction (EF). Assuming MRI estimates (x) as a reference, an excellent correlation was found with volume measured by utilizing the segmentation procedure (y) (y=0.89x + 13.78, r=0.98). The mean error on SV was 8 ml and the mean error on EF was 2%. This study demonstrated that the segmentation technique is reliably applicable on human hearts in clinical practice.

Estimating Mixed Broadleaves Forest Stand Volume Using Dsm Extracted from Digital Aerial Images

NASA Astrophysics Data System (ADS)

Sohrabi, H.

2012-07-01

In mixed old growth broadleaves of Hyrcanian forests, it is difficult to estimate stand volume at plot level by remotely sensed data while LiDar data is absent. In this paper, a new approach has been proposed and tested for estimating stand forest volume. The approach is based on this idea that forest volume can be estimated by variation of trees height at plots. In the other word, the more the height variation in plot, the more the stand volume would be expected. For testing this idea, 120 circular 0.1 ha sample plots with systematic random design has been collected in Tonekaon forest located in Hyrcanian zone. Digital surface model (DSM) measure the height values of the first surface on the ground including terrain features, trees, building etc, which provides a topographic model of the earth's surface. The DSMs have been extracted automatically from aerial UltraCamD images so that ground pixel size for extracted DSM varied from 1 to 10 m size by 1m span. DSMs were checked manually for probable errors. Corresponded to ground samples, standard deviation and range of DSM pixels have been calculated. For modeling, non-linear regression method was used. The results showed that standard deviation of plot pixels with 5 m resolution was the most appropriate data for modeling. Relative bias and RMSE of estimation was 5.8 and 49.8 percent, respectively. Comparing to other approaches for estimating stand volume based on passive remote sensing data in mixed broadleaves forests, these results are more encouraging. One big problem in this method occurs when trees canopy cover is totally closed. In this situation, the standard deviation of height is low while stand volume is high. In future studies, applying forest stratification could be studied.

Penguin lungs and air sacs: implications for baroprotection, oxygen stores and buoyancy.

PubMed

Ponganis, P J; St Leger, J; Scadeng, M

2015-03-01

The anatomy and volume of the penguin respiratory system contribute significantly to pulmonary baroprotection, the body O2 store, buoyancy and hence the overall diving physiology of penguins. Therefore, three-dimensional reconstructions from computerized tomographic (CT) scans of live penguins were utilized to measure lung volumes, air sac volumes, tracheobronchial volumes and total body volumes at different inflation pressures in three species with different dive capacities [Adélie (Pygoscelis adeliae), king (Aptenodytes patagonicus) and emperor (A. forsteri) penguins]. Lung volumes scaled to body mass according to published avian allometrics. Air sac volumes at 30 cm H2O (2.94 kPa) inflation pressure, the assumed maximum volume possible prior to deep dives, were two to three times allometric air sac predictions and also two to three times previously determined end-of-dive total air volumes. Although it is unknown whether penguins inhale to such high volumes prior to dives, these values were supported by (a) body density/buoyancy calculations, (b) prior air volume measurements in free-diving ducks and (c) previous suggestions that penguins may exhale air prior to the final portions of deep dives. Based upon air capillary volumes, parabronchial volumes and tracheobronchial volumes estimated from the measured lung/airway volumes and the only available morphometry study of a penguin lung, the presumed maximum air sac volumes resulted in air sac volume to air capillary/parabronchial/tracheobronchial volume ratios that were not large enough to prevent barotrauma to the non-collapsing, rigid air capillaries during the deepest dives of all three species, and during many routine dives of king and emperor penguins. We conclude that volume reduction of airways and lung air spaces, via compression, constriction or blood engorgement, must occur to provide pulmonary baroprotection at depth. It is also possible that relative air capillary and parabronchial volumes are smaller in these deeper-diving species than in the spheniscid penguin of the morphometry study. If penguins do inhale to this maximum air sac volume prior to their deepest dives, the magnitude and distribution of the body O2 store would change considerably. In emperor penguins, total body O2 would increase by 75%, and the respiratory fraction would increase from 33% to 61%. We emphasize that the maximum pre-dive respiratory air volume is still unknown in penguins. However, even lesser increases in air sac volume prior to a dive would still significantly increase the O2 store. More refined evaluations of the respiratory O2 store and baroprotective mechanisms in penguins await further investigation of species-specific lung morphometry, start-of-dive air volumes and body buoyancy, and the possibility of air exhalation during dives. © 2015. Published by The Company of Biologists Ltd.

Planning for Downtown Circulation Systems. Volume 3. Appendices.

DOT National Transportation Integrated Search

1983-10-01

This volume contains worksheets for estimating circulator patronage, costs, revenues and travel impacts, detailed discussions of estimation and application procedures for the demand models developed, and a case study of the models' application using ...

Hand volume estimates based on a geometric algorithm in comparison to water displacement.

PubMed

Mayrovitz, H N; Sims, N; Hill, C J; Hernandez, T; Greenshner, A; Diep, H

2006-06-01

Assessing changes in upper extremity limb volume during lymphedema therapy is important for determining treatment efficacy and documenting outcomes. Although arm volumes may be determined by tape measure, the suitability of circumference measurements to estimate hand volumes is questionable because of the deviation in circularity of hand shape. Our aim was to develop an alternative measurement procedure and algorithm for routine use to estimate hand volumes. A caliper was used to measure hand width and depth in 33 subjects (66 hands) and volumes (VE) were calculated using an elliptical frustum model. Using regression analysis and limits of agreement (LOA), VE was compared to volumes determined by water displacement (VW), to volumes calculated from tape-measure determined circumferences (VC), and to a trapezoidal model (VT). VW and VE (mean +/- SD) were similar (363 +/- 98 vs. 362 +/-100 ml) and highly correlated; VE = 1.01VW -3.1 ml, r=0.986, p<0.001, with LOA of +/- 33.5 ml and +/- 9.9 %. In contrast, VC (480 +/- 138 ml) and VT (432 +/- 122 ml) significantly overestimated volume (p<0.0001). These results indicate that the elliptical algorithm can be a useful alternative to water displacement when hand volumes are needed and the water displacement method is contra-indicated, impractical to implement, too time consuming or not available.

Patient volume, staffing, and workload in relation to risk-adjusted outcomes in a random stratified sample of UK neonatal intensive care units: a prospective evaluation.

PubMed

Tucker, Janet

2002-01-12

UK recommendations suggest that large neonatal intensive-care units (NICUs) have better outcomes than small units, although this suggestion remains unproven. We assessed whether patient volume, staffing levels, and workload are associated with risk-adjusted outcomes, and with costs or staff wellbeing. 186 UK NICUs were stratified according to volume of patients, nursing provision, and neonatal consultant provision. Primary outcomes were hospital mortality, mortality or cerebral damage, and nosocomial bacteraemia. We studied 13515 infants of all birthweights consecutively admitted to 54 randomly selected NICUs. Multiple logistic regression analyses were done with every primary outcome as the dependent variable. Staff wellbeing and stress were assessed by anonymous mental health index (MHI)-5 questionnaires. Data were available for 13334 (99%) infants. High-volume NICUs treated the sickest infants and had highest crude mortality. Risk-adjusted mortality and mortality or cerebral damage were unrelated to patient volume or staffing provision; however, nosocomial bacteraemia was less frequent in NICUs with low neonatal consultant provision (odds ratio 0.65, 95% CI 0.43-0.98). Mortality was raised with increasing workload in all types of NICUs. Infants admitted at full capacity versus half capacity were about 50% more likely to die, but there was wide uncertainty around this estimate. Most staff had MHI-5 scores that suggested good mental health. The implications of this report for staffing policy, medicolegal risk management, and ethical practice remain to be tested. Centralisation of only the sickest infants could improve efficiency, provided that this does not create excessive workload for staff. Assessment of increased staffing levels that are closer to those in adult intensive care might be appropriate.

Ring profiler: a new method for estimating tree-ring density for improved estimates of carbon storage

Treesearch

David W. Vahey; C. Tim Scott; J.Y. Zhu; Kenneth E. Skog

2012-01-01

Methods for estimating present and future carbon storage in trees and forests rely on measurements or estimates of tree volume or volume growth multiplied by specific gravity. Wood density can vary by tree ring and height in a tree. If data on density by tree ring could be obtained and linked to tree size and stand characteristics, it would be possible to more...

Assessing the Feasibility of Large-Scale Countercyclical Public Job-Creation. Final Report, Volume III. Selected Implications of Public Job-Creation.

ERIC Educational Resources Information Center

Urban Inst., Washington, DC.

This last of a three-volume report of a study done to assess the feasibility of large-scale, countercyclical public job creation covers the findings regarding the priorities among projects, indirect employment effects, skill imbalances, and administrative issues; and summarizes the overall findings, conclusions, and recommendations. (Volume 1,…

Estimators and characteristics of logging residue in California.

Treesearch

James O. Howard; Julianne K. Bulgrin

1986-01-01

Ratios are presented for estimating volume and characteristics of logging residue in California. The ratios relate cubic-foot volume of residue to thousand board feet of timber harvested and to acres harvested. Tables show gross and net volume of residue, with and without bark, by diameter and length classes, by number of pieces per acre, by softwoods and hardwoods, by...

Equations for merchantable volume for subtropical moist and wet forests of Puerto Rico

Treesearch

Thomas J. Brandeis; Olaf Kuegler; Steven A. Knowe

2005-01-01

In Puerto Rico, where locally grown woods are primarily used for furniture and crafts production, estimation of wood volume makes it possible to estimate the monetary value of one of the many commodities and services forests provide to society. In the Puerto Rican forest inventories of 1980 and 1990, workers calculated stem volume directly by applying geometric...

Complex compatible taper and volume estimation systems for red and loblolly pine

Treesearch

John C. Byrne; David D. Reed

1986-01-01

Five equation systems are described which can be used to estimate upper stem diameter, total individual tree cubic-foot volume, and merchantable cubic-foot volumes to any merchantability imit (expressed in terms of diameter or height), both inside and outside bark. The equations provide consistent results since they are mathematically related and are fit using stem...

Uncertainty in peat volume and soil carbon estimated using ground-penetrating radar and probing

Treesearch

Andrew D. Parsekian; Lee Slater; Dimitrios Ntarlagiannis; James Nolan; Stephen D. Sebestyen; Randall K. Kolka; Paul J. Hanson

2012-01-01

Estimating soil C stock in a peatland is highly dependent on accurate measurement of the peat volume. In this study, we evaluated the uncertainty in calculations of peat volume using high-resolution data to resolve the three-dimensional structure of a peat basin based on both direct (push probes) and indirect geophysical (ground-penetrating radar) measurements. We...

Mass and volume contributions to twentieth-century global sea level rise.

PubMed

Miller, Laury; Douglas, Bruce C

2004-03-25

The rate of twentieth-century global sea level rise and its causes are the subjects of intense controversy. Most direct estimates from tide gauges give 1.5-2.0 mm yr(-1), whereas indirect estimates based on the two processes responsible for global sea level rise, namely mass and volume change, fall far below this range. Estimates of the volume increase due to ocean warming give a rate of about 0.5 mm yr(-1) (ref. 8) and the rate due to mass increase, primarily from the melting of continental ice, is thought to be even smaller. Therefore, either the tide gauge estimates are too high, as has been suggested recently, or one (or both) of the mass and volume estimates is too low. Here we present an analysis of sea level measurements at tide gauges combined with observations of temperature and salinity in the Pacific and Atlantic oceans close to the gauges. We find that gauge-determined rates of sea level rise, which encompass both mass and volume changes, are two to three times higher than the rates due to volume change derived from temperature and salinity data. Our analysis supports earlier studies that put the twentieth-century rate in the 1.5-2.0 mm yr(-1) range, but more importantly it suggests that mass increase plays a larger role than ocean warming in twentieth-century global sea level rise.

Exploiting Satellite Archives to Estimate Global Glacier Volume Changes

NASA Astrophysics Data System (ADS)

McNabb, R. W.; Nuth, C.; Kääb, A.; Girod, L.

2017-12-01

In the past decade, the availability of, and ability to process, remote sensing data over glaciers has expanded tremendously. Newly opened satellite image archives, combined with new processing techniques as well as increased computing power and storage capacity, have given the glaciological community the ability to observe and investigate glaciological processes and changes on a truly global scale. In particular, the opening of the ASTER archives provides further opportunities to both estimate and monitor glacier elevation and volume changes globally, including potentially on sub-annual timescales. With this explosion of data availability, however, comes the challenge of seeing the forest instead of the trees. The high volume of data available means that automated detection and proper handling of errors and biases in the data becomes critical, in order to properly study the processes that we wish to see. This includes holes and blunders in digital elevation models (DEMs) derived from optical data or penetration of radar signals leading to biases in DEMs derived from radar data, among other sources. Here, we highlight new advances in the ability to sift through high-volume datasets, and apply these techniques to estimate recent glacier volume changes in the Caucasus Mountains, Scandinavia, Africa, and South America. By properly estimating and correcting for these biases, we additionally provide a detailed accounting of the uncertainties in these estimates of volume changes, leading to more reliable results that have applicability beyond the glaciological community.

Estimating accumulation rates and physical properties of sediment behind a dam: Englebright Lake, Yuba River, northern California

USGS Publications Warehouse

Snyder, Noah P.; Rubin, David M.; Alpers, Charles N.; Childs, Jonathan R.; Curtis, Jennifer A.; Flint, Lorraine E.; Wright, Scott A.

2004-01-01

Studies of reservoir sedimentation are vital to understanding scientific and management issues related to watershed sediment budgets, depositional processes, reservoir operations, and dam decommissioning. Here we quantify the mass, organic content, and grain-size distribution of a reservoir deposit in northern California by two methods of extrapolating measurements of sediment physical properties from cores to the entire volume of impounded material. Englebright Dam, completed in 1940, is located on the Yuba River in the Sierra Nevada foothills. A research program is underway to assess the feasibility of introducing wild anadromous fish species to the river upstream of the dam. Possible management scenarios include removing or lowering the dam, which could cause downstream transport of stored sediment. In 2001 the volume of sediments deposited behind Englebright Dam occupied 25.5% of the original reservoir capacity. The physical properties of this deposit were calculated using data from a coring campaign that sampled the entire reservoir sediment thickness (6–32 m) at six locations in the downstream ∼3/4 of the reservoir. As a result, the sediment in the downstream part of the reservoir is well characterized, but in the coarse, upstream part of the reservoir, only surficial sediments were sampled, so calculations there are more uncertain. Extrapolation from one-dimensional vertical sections of sediment sampled in cores to entire three-dimensional volumes of the reservoir deposit is accomplished via two methods, using assumptions of variable and constant layer thickness. Overall, the two extrapolation methods yield nearly identical estimates of the mass of the reservoir deposit of ∼26 × 106 metric tons (t) of material, of which 64.7–68.5% is sand and gravel. Over the 61 year reservoir history this corresponds to a maximum basin-wide sediment yield of ∼340 t/km2/yr, assuming no contribution from upstream parts of the watershed impounded by other dams. The uncertainties and limitations of the estimates of overall sediment quantities are discussed. Implications for watershed management and future reservoir sedimentation studies are also presented.

Implications of improved diagnostic imaging of small nodal metastases in head and neck cancer: Radiotherapy target volume transformation and dose de-escalation.

PubMed

van den Bosch, Sven; Vogel, Wouter V; Raaijmakers, Cornelis P; Dijkema, Tim; Terhaard, Chris H J; Al-Mamgani, Abrahim; Kaanders, Johannes H A M

2018-05-03

Diagnostic imaging continues to evolve, and now has unprecedented accuracy for detecting small nodal metastasis. This influences the tumor load in elective target volumes and subsequently has consequences for the radiotherapy dose required to control disease in these volumes. Small metastases that used to remain subclinical and were included in elective volumes, will nowadays be detected and included in high-dose volumes. Consequentially, high-dose volumes will more often contain low-volume disease. These target volume transformations lead to changes in the tumor burden in elective and "gross" tumor volumes with implications for the radiotherapy dose prescribed to these volumes. For head and neck tumors, nodal staging has evolved from mere palpation to combinations of high-resolution imaging modalities. A traditional nodal gross tumor volume in the neck typically had a minimum diameter of 10-15 mm, while nowadays much smaller tumor deposits are detected in lymph nodes. However, the current dose levels for elective nodal irradiation were empirically determined in the 1950s, and have not changed since. In this report the radiobiological consequences of target volume transformation caused by modern imaging of the neck are evaluated, and theoretically derived reductions of dose in radiotherapy for head and neck cancer are proposed. The concept of target volume transformation and subsequent strategies for dose adaptation applies to many other tumor types as well. Awareness of this concept may result in new strategies for target definition and selection of dose levels with the aim to provide optimal tumor control with less toxicity. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Evaluation of concentrations of pharmaceuticals detected in sewage influents in Japan by using annual shipping and sales data.

PubMed

Azuma, Takashi; Nakada, Norihide; Yamashita, Naoyuki; Tanaka, Hiroaki

2015-11-01

A year-round monitoring survey of sewage flowing into sewage treatment plants located in urban Japan was conducted by targeting seven representative pharmaceutical components-atenolol (ATL), ciprofloxacin (CFX), clarithromycin (CTM), diclofenac (DCF), diltiazem (DTZ), disopyramide (DSP), and sulpiride (SPR)-detected in the river environment. For each of these components, two types of predicted concentration were estimated on the basis of two types of data (the shipping volume and sales volume of each component). The measured concentration of each component obtained through the survey and the two types of estimated predicted concentration of each component were then compared. The correspondence ratio between the predicted concentration estimated from the shipping volume of the component and the measured concentration (predicted concentration/measured concentration) was, for ATL, 3.1; CFX, 1.4; CTM, 1.4; DCF, 0.2; DTZ, 0.9; DSP, 11.6; and SPR, 1.1. The correspondence ratio between the predicted concentration estimated from the sales volume of the component and the measured concentration was, for ATL, 0.5; CFX, 1.1; CTM, 0.8; DCF, 0.1; DTZ, 0.2; DSP, 0.7; and SPR, 0.8. Although a generally corresponding trend was seen regardless of whether the prediction was based on shipping volume or sales volume, the predicted concentrations estimated from the shipping volumes of all components expect DSP were found, to our knowledge for the first time in Japan, to correspond better than those based on sales volumes to the measured concentrations. These findings should help to improve the prediction accuracy of concentrations of pharmaceutical components in river waters. Copyright © 2015 Elsevier Ltd. All rights reserved.

Factors Affecting Prostate Volume Estimation in Computed Tomography Images

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

Yang, Cheng-Hsiu; Wang, Shyh-Jen; Institute of Biomedical Engineering, National Yang Ming University, Taipei, Taiwan

2011-04-01

The aim of this study was to investigate how apex-localizing methods and the computed tomography (CT) slice thickness affected the CT-based prostate volume estimation. Twenty-eight volunteers underwent evaluations of prostate volume by CT, where the contour segmentations were performed by three observers. The bottom of ischial tuberosities (ITs) and the bulb of the penis were used as reference positions to locate the apex, and the distances to the apex were recorded as 1.3 and 2.0 cm, respectively. Interobserver variations to locate ITs and the bulb of the penis were, on average, 0.10 cm (range 0.03-0.38 cm) and 0.30 cm (rangemore » 0.00-0.98 cm), respectively. The range of CT slice thickness varied from 0.08-0.48 cm and was adopted to examine the influence of the variation on volume estimation. The volume deviation from the reference case (0.08 cm), which increases in tandem with the slice thickness, was within {+-} 3 cm{sup 3}, regardless of the adopted apex-locating reference positions. In addition, the maximum error of apex identification was 1.5 times of slice thickness. Finally, based on the precise CT films and the methods of apex identification, there were strong positive correlation coefficients for the estimated prostate volume by CT and the transabdominal ultrasonography, as found in the present study (r > 0.87; p < 0.0001), and this was confirmed by Bland-Altman analysis. These results will help to identify factors that affect prostate volume calculation and to contribute to the improved estimation of the prostate volume based on CT images.« less

Benefit-Cost Analysis of Integrated Paratransit Systems : Volume 6. Technical Appendices.

DOT National Transportation Integrated Search

1979-09-01

This last volume, includes five technical appendices which document the methodologies used in the benefit-cost analysis. They are the following: Scenario analysis methodology; Impact estimation; Example of impact estimation; Sensitivity analysis; Agg...

Imputing missing data via sparse reconstruction techniques.

DOT National Transportation Integrated Search

2017-06-01

The State of Texas does not currently have an automated approach for estimating volumes for links without counts. This research project proposes the development of an automated system to efficiently estimate the traffic volumes on uncounted links, in...

Estimating value and volume of ponderosa pine trees by equations.

Treesearch

Martin E. Plank

1981-01-01

Equations for estimating the selling value and tally volume for ponderosa pine lumber from the standing trees are described. Only five characteristics are required for the equations. Development and application of the system are described.

The persistence of the large volumes in black holes

NASA Astrophysics Data System (ADS)

Ong, Yen Chin

2015-08-01

Classically, black holes admit maximal interior volumes that grow asymptotically linearly in time. We show that such volumes remain large when Hawking evaporation is taken into account. Even if a charged black hole approaches the extremal limit during this evolution, its volume continues to grow; although an exactly extremal black hole does not have a "large interior". We clarify this point and discuss the implications of our results to the information loss and firewall paradoxes.

Effects of the liver volume and donor steatosis on errors in the estimated standard liver volume.

PubMed

Siriwardana, Rohan Chaminda; Chan, See Ching; Chok, Kenneth Siu Ho; Lo, Chung Mau; Fan, Sheung Tat

2011-12-01

An accurate assessment of donor and recipient liver volumes is essential in living donor liver transplantation. Many liver donors are affected by mild to moderate steatosis, and steatotic livers are known to have larger volumes. This study analyzes errors in liver volume estimation by commonly used formulas and the effects of donor steatosis on these errors. Three hundred twenty-five Asian donors who underwent right lobe donor hepatectomy were the subjects of this study. The percentage differences between the liver volumes from computed tomography (CT) and the liver volumes estimated with each formula (ie, the error percentages) were calculated. Five popular formulas were tested. The degrees of steatosis were categorized as follows: no steatosis [n = 178 (54.8%)], ≤ 10% steatosis [n = 128 (39.4%)], and >10% to 20% steatosis [n = 19 (5.8%)]. The median errors ranged from 0.6% (7 mL) to 24.6% (360 mL). The lowest was seen with the locally derived formula. All the formulas showed a significant association between the error percentage and the CT liver volume (P < 0.001). Overestimation was seen with smaller liver volumes, whereas underestimation was seen with larger volumes. The locally derived formula was most accurate when the liver volume was 1001 to 1250 mL. A multivariate analysis showed that the estimation error was dependent on the liver volume (P = 0.001) and the anthropometric measurement that was used in the calculation (P < 0.001) rather than steatosis (P ≥ 0.07). In conclusion, all the formulas have a similar pattern of error that is possibly related to the anthropometric measurement. Clinicians should be aware of this pattern of error and the liver volume with which their formula is most accurate. Copyright © 2011 American Association for the Study of Liver Diseases.

Quantifying Standing Dead Tree Volume and Structural Loss with Voxelized Terrestrial Lidar Data

NASA Astrophysics Data System (ADS)

Popescu, S. C.; Putman, E.

2017-12-01

Standing dead trees (SDTs) are an important forest component and impact a variety of ecosystem processes, yet the carbon pool dynamics of SDTs are poorly constrained in terrestrial carbon cycling models. The ability to model wood decay and carbon cycling in relation to detectable changes in tree structure and volume over time would greatly improve such models. The overall objective of this study was to provide automated aboveground volume estimates of SDTs and automated procedures to detect, quantify, and characterize structural losses over time with terrestrial lidar data. The specific objectives of this study were: 1) develop an automated SDT volume estimation algorithm providing accurate volume estimates for trees scanned in dense forests; 2) develop an automated change detection methodology to accurately detect and quantify SDT structural loss between subsequent terrestrial lidar observations; and 3) characterize the structural loss rates of pine and oak SDTs in southeastern Texas. A voxel-based volume estimation algorithm, "TreeVolX", was developed and incorporates several methods designed to robustly process point clouds of varying quality levels. The algorithm operates on horizontal voxel slices by segmenting the slice into distinct branch or stem sections then applying an adaptive contour interpolation and interior filling process to create solid reconstructed tree models (RTMs). TreeVolX estimated large and small branch volume with an RMSE of 7.3% and 13.8%, respectively. A voxel-based change detection methodology was developed to accurately detect and quantify structural losses and incorporated several methods to mitigate the challenges presented by shifting tree and branch positions as SDT decay progresses. The volume and structural loss of 29 SDTs, composed of Pinus taeda and Quercus stellata, were successfully estimated using multitemporal terrestrial lidar observations over elapsed times ranging from 71 - 753 days. Pine and oak structural loss rates were characterized by estimating the amount of volumetric loss occurring in 20 equal-interval height bins of each SDT. Results showed that large pine snags exhibited more rapid structural loss in comparison to medium-sized oak snags in this study.

Wyoming Low-Volume Roads Traffic Volume Estimation

DOT National Transportation Integrated Search

2015-10-01

Low-volume roads are excluded from regular traffic counts except on a need to know basis. But needs for traffic volume data on low-volume roads in road infrastructure management, safety, and air quality analysis have necessitated regular traffic volu...

An investigation of spectral change as influenced by irrigation and evapotranspiration volume estimation in western Nebraska

USGS Publications Warehouse

Seevers, P.M.; Sadowski, F.C.; Lauer, D.T.

1990-01-01

Retrospective satellite image data were evaluated for their ability to demonstrate the influence of center-pivot irrigation development in western Nebraska on spectral change and climate-related factors for the region. Periodic images of an albedo index and a normalized difference vegetation index (NDVI) were generated from calibrated Landsat multispectral scanner (MSS) data and used to monitor spectral changes associated with irrigation development from 1972 through 1986. The albedo index was not useful for monitoring irrigation development. For the NDVI, it was found that proportions of counties in irrigated agriculture, as discriminated by a threshold, were more highly correlated with reported ground estimates of irrigated agriculture than were county mean greenness values. A similar result was achieved when using coarse resolution Advanced Very High Resolution Radiometer (AVHRR) image data for estimating irrigated agriculture. The NDVI images were used to evaluate a procedure for making areal estimates of actual evapotranspiration (ET) volumes. Estimates of ET volumes for test counties, using reported ground acreages and corresponding standard crop coefficients, were correlated with the estimates of ET volume using crop coefficients scaled to NDVI values and pixel counts of crop areas. These county estimates were made under the assumption that soil water availability was unlimited. For nonirrigated vegetation, this may result in over-estimation of ET volumes. Ground information regarding crop types and acreages are required to derive the NDVI scaling factor. Potential ET, estimated with the Jensen-Haise model, is common to both methods. These results, achieved with both MSS and AVHRR data, show promise for providing climatologically important land surface information for regional and global climate models. ?? 1990 Kluwer Academic Publishers.

Greater-than-Class C low-level radioactive waste characterization: Estimated volumes, radionuclide activities, and other characteristics

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

Hulse, R.A.

1991-08-01

Planning for storage or disposal of greater-than-Class C low-level radioactive waste (GTCC LLW) requires characterization of that waste to estimate volumes, radionuclide activities, and waste forms. Data from existing literature, disposal records, and original research were used to estimate the characteristics and project volumes and radionuclide activities to the year 2035. GTCC LLW is categorized as: nuclear utilities waste, sealed sources waste, DOE-held potential GTCC LLW; and, other generator waste. It has been determined that the largest volume of those wastes, approximately 57%, is generated by nuclear power plants. The Other Generator waste category contributes approximately 10% of the totalmore » GTCC LLW volume projected to the year 2035. Waste held by the Department of Energy, which is potential GTCC LLW, accounts for nearly 33% of all waste projected to the year 2035; however, no disposal determination has been made for that waste. Sealed sources are less than 0.2% of the total projected volume of GTCC LLW.« less

An estimation of vehicle kilometer traveled and on-road emissions using the traffic volume and travel speed on road links in Incheon City.

PubMed

Jung, Sungwoon; Kim, Jounghwa; Kim, Jeongsoo; Hong, Dahee; Park, Dongjoo

2017-04-01

The objective of this study is to estimate the vehicle kilometer traveled (VKT) and on-road emissions using the traffic volume in urban. We estimated two VKT; one is based on registered vehicles and the other is based on traffic volumes. VKT for registered vehicles was 2.11 times greater than that of the applied traffic volumes because each VKT estimation method is different. Therefore, we had to define the inner VKT is moved VKT inner in urban to compare two values. Also, we focused on freight modes because these are discharged much air pollutant emissions. From analysis results, we found middle and large trucks registered in other regions traveled to target city in order to carry freight, target city has included many industrial and logistics areas. Freight is transferred through the harbors, large logistics centers, or via locations before being moved to the final destination. During this process, most freight is moved by middle and large trucks, and trailers rather than small trucks for freight import and export. Therefore, these trucks from other areas are inflow more than registered vehicles. Most emissions from diesel trucks had been overestimated in comparison to VKT from applied traffic volumes in target city. From these findings, VKT is essential based on traffic volume and travel speed on road links in order to estimate accurately the emissions of diesel trucks in target city. Our findings support the estimation of the effect of on-road emissions on urban air quality in Korea. Copyright © 2016. Published by Elsevier B.V.

Factors influencing the height of Hawaiian lava fountains: implications for the use of fountain height as an indicator of magma gas content

USGS Publications Warehouse

Parfitt, E.A.; Wilson, L.; Neal, C.A.

1995-01-01

The heights of lava fountains formed in Hawaiian-style eruptions are controlled by magma gas content, volume flux and the amounts of lava re-entrainment and gas bubble coalescence. Theoretical models of lava fountaining are used to analyse data on lava fountain height variations collected during the 1983-1986 Pu'u 'O'o vent of Kilauea volcano, Hawaii. The results show that the variable fountain heights can be largely explained by the impact of variations in volume flux and amount of lava re-entrainment on erupting magmas with a constant gas content of ???0.32 wt.% H2O. However, the gas content of the magma apparently declined by ???0.05 wt.% during the last 10 episodes of the eruption series and this decline is attributed to more extensive pre-eruption degassing due to a shallowing of the sub-vent feeder dike. It is concluded that variations in lava fountain height cannot be simply interpreted as variations in gas content, as has previously been suggested, but that fountain height can still be a useful guide to minimum gas contents. Where sufficient data are available on eruptive volume fluxes and extent of lava entrainment, greatly improved estimates can be made of magma gas content from lava fountain height. ?? 1995 Springer-Verlag.

Biasing and High-Order Statistics from the Southern-Sky Redshift Survey

NASA Astrophysics Data System (ADS)

Benoist, C.; Cappi, A.; da Costa, L. N.; Maurogordato, S.; Bouchet, F. R.; Schaeffer, R.

1999-04-01

We analyze different volume-limited samples extracted from the Southern-Sky Redshift Survey (SSRS2), using counts-in-cells to compute the count probability distribution function (CPDF). From the CPDF we derive volume-averaged correlation functions to fourth order and the normalized skewness and kurtosis S3=ξ3¯/ξ¯22 and S4=ξ4¯/ξ¯32. We find that the data satisfies the hierarchical relations in the range 0.3<~ξ2¯<~10. In this range we find S3 to be scale independent, with a value of ~1.8, in good agreement with the values measured from other optical redshift surveys probing different volumes, but significantly smaller than that inferred from the Automatic Plate Measuring Facility (APM) angular catalog. In addition, the measured values of S3 do not show a significant dependence on the luminosity of the galaxies considered. This result is supported by several tests of systematic errors that could affect our measures and estimates of the cosmic variance determined from mock catalogs extracted from N-body simulations. This result is in marked contrast to what would be expected from the strong dependence of the two-point correlation function on luminosity in the framework of a linear biasing model. We discuss the implications of our results and compare them to some recent models of the galaxy distribution that address the problem of bias.

Estimating Highway Volumes Using Vehicle Probe Data - Proof of Concept: Preprint

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

Hou, Yi; Young, Stanley E; Sadabadi, Kaveh

This paper examines the feasibility of using sampled commercial probe data in combination with validated continuous counter data to accurately estimate vehicle volume across the entire roadway network, for any hour during the year. Currently either real time or archived volume data for roadways at specific times are extremely sparse. Most volume data are average annual daily traffic (AADT) measures derived from the Highway Performance Monitoring System (HPMS). Although methods to factor the AADT to hourly averages for typical day of week exist, actual volume data is limited to a sparse collection of locations in which volumes are continuously recorded.more » This paper explores the use of commercial probe data to generate accurate volume measures that span the highway network providing ubiquitous coverage in space, and specific point-in-time measures for a specific date and time. The paper examines the need for the data, fundamental accuracy limitations based on a basic statistical model that take into account the sampling nature of probe data, and early results from a proof of concept exercise revealing the potential of probe type data calibrated with public continuous count data to meet end user expectations in terms of accuracy of volume estimates.« less

Self-Interaction Chromatography of mAbs: Accurate Measurement of Dead Volumes.

PubMed

Hedberg, S H M; Heng, J Y Y; Williams, D R; Liddell, J M

2015-12-01

Measurement of the second virial coefficient B22 for proteins using self-interaction chromatography (SIC) is becoming an increasingly important technique for studying their solution behaviour. In common with all physicochemical chromatographic methods, measuring the dead volume of the SIC packed column is crucial for accurate retention data; this paper examines best practise for dead volume determination. SIC type experiments using catalase, BSA, lysozyme and a mAb as model systems are reported, as well as a number of dead column measurements. It was observed that lysozyme and mAb interacted specifically with Toyopearl AF-Formyl dead columns depending upon pH and [NaCl], invalidating their dead volume usage. Toyopearl AF-Amino packed dead columns showed no such problems and acted as suitable dead columns without any solution condition dependency. Dead volume determinations using dextran MW standards with protein immobilised SIC columns provided dead volume estimates close to those obtained using Toyopearl AF-Amino dead columns. It is concluded that specific interactions between proteins, including mAbs, and select SIC support phases can compromise the use of some standard approaches for estimating the dead volume of SIC columns. Two other methods were shown to provide good estimates for the dead volume.

From field data to volumes: constraining uncertainties in pyroclastic eruption parameters

NASA Astrophysics Data System (ADS)

Klawonn, Malin; Houghton, Bruce F.; Swanson, Donald A.; Fagents, Sarah A.; Wessel, Paul; Wolfe, Cecily J.

2014-07-01

In this study, we aim to understand the variability in eruption volume estimates derived from field studies of pyroclastic deposits. We distributed paper maps of the 1959 Kīlauea Iki tephra to 101 volcanologists worldwide, who produced hand-drawn isopachs. Across the returned maps, uncertainty in isopach areas is 7 % across the well-sampled deposit but increases to over 30 % for isopachs that are governed by the largest and smallest thickness measurements. We fit the exponential, power-law, and Weibull functions through the isopach thickness versus area1/2 values and find volume estimate variations up to a factor of 4.9 for a single map. Across all maps and methodologies, we find an average standard deviation for a total volume of s = 29 %. The volume uncertainties are largest for the most proximal ( s = 62 %) and distal field ( s = 53 %) and small for the densely sampled intermediate deposit ( s = 8 %). For the Kīlauea Iki 1959 eruption, we find that the deposit beyond the 5-cm isopach contains only 2 % of the total erupted volume, whereas the near-source deposit contains 48 % and the intermediate deposit 50 % of the total volume. Thus, the relative uncertainty within each zone impacts the total volume estimates differently. The observed uncertainties for the different deposit regions in this study illustrate a fundamental problem of estimating eruption volumes: while some methodologies may provide better fits to the isopach data or rely on fewer free parameters, the main issue remains the predictive capabilities of the empirical functions for the regions where measurements are missing.

Cost and price estimate of Brayton and Stirling engines in selected production volumes

NASA Technical Reports Server (NTRS)

Fortgang, H. R.; Mayers, H. F.

1980-01-01

The methods used to determine the production costs and required selling price of Brayton and Stirling engines modified for use in solar power conversion units are presented. Each engine part, component and assembly was examined and evaluated to determine the costs of its material and the method of manufacture based on specific annual production volumes. Cost estimates are presented for both the Stirling and Brayton engines in annual production volumes of 1,000, 25,000, 100,000 and 400,000. At annual production volumes above 50,000 units, the costs of both engines are similar, although the Stirling engine costs are somewhat lower. It is concluded that modifications to both the Brayton and Stirling engine designs could reduce the estimated costs.

Relationships between regional cerebellar volume and sensorimotor and cognitive function in young and older adults

PubMed Central

Bernard, Jessica A.; Seidler, Rachael D.

2013-01-01

The cerebellum has been implicated in both sensorimotor and cognitive function, but is known to undergo volumetric declines with advanced age. Individual differences in regional cerebellar volume may therefore provide insight into performance variability across the lifespan, as has been shown with other brain structures and behaviors. Here, we investigated whether there are regional age differences in cerebellar volume in young and older adults, and whether these volumes explain, in part, individual differences in sensorimotor and cognitive task performance. We found that older adults had smaller cerebellar volume than young adults; specifically, lobules in the anterior cerebellum were more impacted by age. Multiple regression analyses for both age groups revealed associations between sensorimotor task performance in several domains (balance, choice reaction time, and timing) and regional cerebellar volume. There were also relationships with working memory, but none with measures of general cognitive or executive function. Follow-up analyses revealed several differential relationships with age between regional volume and sensorimotor performance. These relationships were predominantly selective to cerebellar regions that have been implicated in cognitive functions. Therefore, it may be the cognitive aspects of sensorimotor task performance that are best explained by individual differences in regional cerebellar volumes. In sum, our results demonstrate the importance of regional cerebellar volume with respect to both sensorimotor and cognitive performance, and we provide additional insight into the role of the cerebellum in age-related performance declines. PMID:23625382

Revised tephra volumes for Cascade Range volcanoes

NASA Astrophysics Data System (ADS)

Nathenson, Manuel

2017-07-01

Isopach maps from tephra eruptions from Mount St. Helens were reported in Carey et al. (1995) and for tephra eruptions from Glacier Peak in Gardner et al. (1998). For exponential thinning, the isopach data only define a single slope on a log thickness versus square root of area plot. Carey et al. (1995) proposed a model that was used to estimate a second slope, and volumes were presented in both studies using this model. A study by Sulpizio (2005) for estimating the second slope and square root of area where the lines intersect involves a systematic analysis of many eruptions to provide correlation equations. The purpose of this paper is to recalculate the volumes of Cascades eruptions and compare results from the two methods. In order to gain some perspective on the methods for estimating the second slope, we use data for thickness versus distance beyond the last isopach that are available for some of the larger eruptions in the Cascades. The thickness versus square root of area method is extended to thickness versus distance by developing an approximate relation between the two assuming elliptical isopachs with the source at one of the foci. Based on the comparisons made between the Carey et al. (1995) and Sulpizio (2005) methods, it is felt that the later method provides a better estimate of the second slope. For Mount St. Helens, the estimates of total volume using the Sulpizio (2005) method are generally smaller than those using the Carey et al. (1995) method. For the volume estimates of Carey et al. (1995), the volume of the May 18, 1980, eruption of Mount St. Helens is smaller than six of the eight previous eruptions. With the new volumes using the Sulpizio (2005) method, the 1980 eruption is smaller in volume than the upper end of the range for only three of the layers (Wn, Ye, and Yn) and is the same size as layer We. Thus the 1980 eruption becomes representative of the mid-range of volumes rather than being in the lower range.

Revised tephra volumes for Cascade Range volcanoes

USGS Publications Warehouse

Nathenson, Manuel

2017-01-01

Isopach maps from tephra eruptions from Mount St. Helens were reported in Carey et al. (1995) and for tephra eruptions from Glacier Peak in Gardner et al. (1998). For exponential thinning, the isopach data only define a single slope on a log thickness versus square root of area plot. Carey et al. (1995) proposed a model that was used to estimate a second slope, and volumes were presented in both studies using this model. A study by Sulpizio (2005) for estimating the second slope and square root of area where the lines intersect involves a systematic analysis of many eruptions to provide correlation equations. The purpose of this paper is to recalculate the volumes of Cascades eruptions and compare results from the two methods. In order to gain some perspective on the methods for estimating the second slope, we use data for thickness versus distance beyond the last isopach that are available for some of the larger eruptions in the Cascades. The thickness versus square root of area method is extended to thickness versus distance by developing an approximate relation between the two assuming elliptical isopachs with the source at one of the foci. Based on the comparisons made between the Carey et al. (1995) and Sulpizio (2005) methods, it is felt that the later method provides a better estimate of the second slope. For Mount St. Helens, the estimates of total volume using the Sulpizio (2005) method are generally smaller than those using the Carey et al. (1995) method. For the volume estimates of Carey et al. (1995), the volume of the May 18, 1980, eruption of Mount St. Helens is smaller than six of the eight previous eruptions. With the new volumes using the Sulpizio (2005) method, the 1980 eruption is smaller in volume than the upper end of the range for only three of the layers (Wn, Ye, and Yn) and is the same size as layer We. Thus the 1980 eruption becomes representative of the mid-range of volumes rather than being in the lower range.

Improving observational study estimates of treatment effects using joint modeling of selection effects and outcomes: the case of AAA repair.

PubMed

O'Malley, A James; Cotterill, Philip; Schermerhorn, Marc L; Landon, Bruce E

2011-12-01

When 2 treatment approaches are available, there are likely to be unmeasured confounders that influence choice of procedure, which complicates estimation of the causal effect of treatment on outcomes using observational data. To estimate the effect of endovascular (endo) versus open surgical (open) repair, including possible modification by institutional volume, on survival after treatment for abdominal aortic aneurysm, accounting for observed and unobserved confounding variables. Observational study of data from the Medicare program using a joint model of treatment selection and survival given treatment to estimate the effects of type of surgery and institutional volume on survival. We studied 61,414 eligible repairs of intact abdominal aortic aneurysms during 2001 to 2004. The outcome, perioperative death, is defined as in-hospital death or death within 30 days of operation. The key predictors are use of endo, transformed endo and open volume, and endo-volume interactions. There is strong evidence of nonrandom selection of treatment with potential confounding variables including institutional volume and procedure date, variables not typically adjusted for in clinical trials. The best fitting model included heterogeneous transformations of endo volume for endo cases and open volume for open cases as predictors. Consistent with our hypothesis, accounting for unmeasured selection reduced the mortality benefit of endo. The effect of endo versus open surgery varies nonlinearly with endo and open volume. Accounting for institutional experience and unmeasured selection enables better decision-making by physicians making treatment referrals, investigators evaluating treatments, and policy makers.

It’s what’s inside that counts: Egg contaminant concentrations are influenced by estimates of egg density, egg volume, and fresh egg mass

USGS Publications Warehouse

Herzog, Mark; Ackerman, Joshua T.; Eagles-Smith, Collin A.; Hartman, Christopher

2016-01-01

In egg contaminant studies, it is necessary to calculate egg contaminant concentrations on a fresh wet weight basis and this requires accurate estimates of egg density and egg volume. We show that the inclusion or exclusion of the eggshell can influence egg contaminant concentrations, and we provide estimates of egg density (both with and without the eggshell) and egg-shape coefficients (used to estimate egg volume from egg morphometrics) for American avocet (Recurvirostra americana), black-necked stilt (Himantopus mexicanus), and Forster’s tern (Sterna forsteri). Egg densities (g/cm3) estimated for whole eggs (1.056 ± 0.003) were higher than egg densities estimated for egg contents (1.024 ± 0.001), and were 1.059 ± 0.001 and 1.025 ± 0.001 for avocets, 1.056 ± 0.001 and 1.023 ± 0.001 for stilts, and 1.053 ± 0.002 and 1.025 ± 0.002 for terns. The egg-shape coefficients for egg volume (K v ) and egg mass (K w ) also differed depending on whether the eggshell was included (K v = 0.491 ± 0.001; K w = 0.518 ± 0.001) or excluded (K v = 0.493 ± 0.001; K w = 0.505 ± 0.001), and varied among species. Although egg contaminant concentrations are rarely meant to include the eggshell, we show that the typical inclusion of the eggshell in egg density and egg volume estimates results in egg contaminant concentrations being underestimated by 6–13 %. Our results demonstrate that the inclusion of the eggshell significantly influences estimates of egg density, egg volume, and fresh egg mass, which leads to egg contaminant concentrations that are biased low. We suggest that egg contaminant concentrations be calculated on a fresh wet weight basis using only internal egg-content densities, volumes, and masses appropriate for the species. For the three waterbirds in our study, these corrected coefficients are 1.024 ± 0.001 for egg density, 0.493 ± 0.001 for K v , and 0.505 ± 0.001 for K w .

Cubic-foot tree volumes and product recoveries for eastern redcedar in the Ozarks

Treesearch

Leland F. Hanks

1979-01-01

Tree volume tables and equations for eastern redcedar are presented for gross volume, cant volume, and volume of sawmill residue. These volumes, when multiplied by the average value per cubic foot of cants and residue, provide a way to estimate tree value.

Multistage variable probability forest volume inventory. [Defiance Unit of the Navajo Nation in Arizona and Colorado

NASA Technical Reports Server (NTRS)

Anderson, J. E. (Principal Investigator)

1979-01-01

The net board foot volume (Scribner log rule) of the standing Ponderosa pine timber on the Defiance Unit of the Navajo Nation's forested land was estimated using a multistage forest volume inventory scheme with variable sample selection probabilities. The inventory designed to accomplish this task required that both LANDSAT MSS digital data and aircraft acquired data be used to locate one acre ground splits, which were subsequently visited by ground teams conducting detailed tree measurements using an optical dendrometer. The dendrometer measurements were then punched on computer input cards and were entered in a computer program developed by the U.S. Forest Service. The resulting individual tree volume estimates were then expanded through the use of a statistically defined equation to produce the volume estimate for the entire area which includes 192,026 acres and is approximately a 44% the total forested area of the Navajo Nation.

Bivariate Heritability of Total and Regional Brain Volumes: the Framingham Study

PubMed Central

DeStefano, Anita L.; Seshadri, Sudha; Beiser, Alexa; Atwood, Larry D.; Massaro, Joe M.; Au, Rhoda; Wolf, Philip A.; DeCarli, Charles

2009-01-01

Heritability and genetic and environmental correlations of total and regional brain volumes were estimated from a large, generally healthy, community-based sample, to determine if there are common elements to the genetic influence of brain volumes and white matter hyperintensity volume. There were 1538 Framingham Heart Study participants with brain volume measures from quantitative magnetic resonance imaging (MRI) who were free of stroke and other neurological disorders that might influence brain volumes and who were members of families with at least two Framingham Heart Study participants. Heritability was estimated using variance component methodology and adjusting for the components of the Framingham stroke risk profile. Genetic and environmental correlations between traits were obtained from bivariate analysis. Heritability estimates ranging from 0.46 to 0.60, were observed for total brain, white matter hyperintensity, hippocampal, temporal lobe, and lateral ventricular volumes. Moderate, yet significant, heritability was observed for the other measures. Bivariate analyses demonstrated that relationships between brain volume measures, except for white matter hyperintensity, reflected both moderate to strong shared genetic and shared environmental influences. This study confirms strong genetic effects on brain and white matter hyperintensity volumes. These data extend current knowledge by showing that these two different types of MRI measures do not share underlying genetic or environmental influences. PMID:19812462

The Impact of Surgeon Volume on Perioperative Outcomes in Hysterectomy

PubMed Central

Vree, Florentien E. M.; Cohen, Sarah L.; Chavan, Niraj

2014-01-01

Background and Objectives: To estimate the effect of surgeon volume on key perioperative outcomes after all modes of hysterectomy. Methods: We performed a review of 1914 hysterectomies performed at a large, academic tertiary-care hospital. Women who underwent abdominal, laparoscopic, vaginal, or robotic hysterectomy for benign non-obstetric indications in 2006, 2009, and 2010 were included. Results: Gynecologic surgeons were categorized according their average annual hysterectomy case volume: low volume (<11 cases per year), intermediate volume (11–50 cases per year), and high-volume (>51 cases per year). Taking all modes of hysterectomy together, surgeries performed by high-volume surgeons required a shorter operative time (155.11 minutes vs 199.19–203.35 minutes, P < .001) and resulted in less estimated blood loss compared with low- and intermediate-volume surgeons (161.09 mL vs 205.58–237.96 mL, P < .001). The 3 surgical volume groups did not differ from each other significantly in the conversion to laparotomy, readmission rate, or incidence of intraoperative or postoperative complications. These findings were maintained when subgroup analyses were performed by type of hysterectomy, with few exceptions. In the subgroup of vaginal hysterectomies by intermediate-volume surgeons, there were slightly more postoperative complications. There were fewer intraoperative complications in laparoscopic/robotic hysterectomies performed by high-volume surgeons, though not statistically significant. Conclusions: Hysterectomies performed by high-volume surgeons at our institution during the 3-year study period were associated with shorter operative times and less estimated blood loss. PMID:24960479

Wildlife conservation in fragmented tropical forests: A case of South Garo Hills, Meghalaya, North East India

Treesearch

Ashish Kumar; Bruce G. Marcot; Rohitkumar Patel

2017-01-01

This volume presents findings on, and implications for, wildlife conservation in the tropical forests in Garo Hills of Meghalaya state in the North East India. A companion volume presented the findings on forest fragmentation due to practice of slash and burn agriculture in the region. Both of the volumes summarize work completed over more than a decade on...

Joint Hampton-Michigan Program for Training Minority and Women Researchers. Volume II of II Volumes. Final Report.

ERIC Educational Resources Information Center

Michigan Univ., Ann Arbor. School of Education.

The papers presented in this volume are the team research reports of the Joint Hampton-Michigan Program conducted in 1979-1980 for junior faculty members of the Hampton Institute (Virginia) and graduate students and faculty members of the University of Michigan. The titles of the papers are: (1) Social and Economic Implications of Teacher Training…

Implications of the Alaska Education Satellite Communications Demonstration for Technological and Educational Policymakers. First Annual Report. Volume II: Supporting Materials.

ERIC Educational Resources Information Center

Practical Concepts, Inc., Washington, DC.

This volume contains the raw data and descriptive materials which form the basis of Volume I, "Analysis of the Demonstration." The information is divided into three categories: (1) description of the overall study plan, (2) compendium of user reaction to program, and (3) a chronology of critical events and their documentary basis. A…

Costing the supply chain for delivery of ACT and RDTs in the public sector in Benin and Kenya.

PubMed

Shretta, Rima; Johnson, Brittany; Smith, Lisa; Doumbia, Seydou; de Savigny, Don; Anupindi, Ravi; Yadav, Prashant

2015-02-05

Studies have shown that supply chain costs are a significant proportion of total programme costs. Nevertheless, the costs of delivering specific products are poorly understood and ballpark estimates are often used to inadequately plan for the budgetary implications of supply chain expenses. The purpose of this research was to estimate the country level costs of the public sector supply chain for artemisinin-based combination therapy (ACT) and rapid diagnostic tests (RDTs) from the central to the peripheral levels in Benin and Kenya. A micro-costing approach was used and primary data on the various cost components of the supply chain was collected at the central, intermediate, and facility levels between September and November 2013. Information sources included central warehouse databases, health facility records, transport schedules, and expenditure reports. Data from document reviews and semi-structured interviews were used to identify cost inputs and estimate actual costs. Sampling was purposive to isolate key variables of interest. Survey guides were developed and administered electronically. Data were extracted into Microsoft Excel, and the supply chain cost per unit of ACT and RDT distributed by function and level of system was calculated. In Benin, supply chain costs added USD 0.2011 to the initial acquisition cost of ACT and USD 0.3375 to RDTs (normalized to USD 1). In Kenya, they added USD 0.2443 to the acquisition cost of ACT and USD 0.1895 to RDTs (normalized to USD 1). Total supply chain costs accounted for more than 30% of the initial acquisition cost of the products in some cases and these costs were highly sensitive to product volumes. The major cost drivers were found to be labour, transport, and utilities with health facilities carrying the majority of the cost per unit of product. Accurate cost estimates are needed to ensure adequate resources are available for supply chain activities. Product volumes should be considered when costing supply chain functions rather than dollar value. Further work is needed to develop extrapolative costing models that can be applied at country level without extensive micro-costing exercises. This will allow other countries to generate more accurate estimates in the future.

Micro CT based truth estimation of nodule volume

NASA Astrophysics Data System (ADS)

Kinnard, L. M.; Gavrielides, M. A.; Myers, K. J.; Zeng, R.; Whiting, B.; Lin-Gibson, S.; Petrick, N.

2010-03-01

With the advent of high-resolution CT, three-dimensional (3D) methods for nodule volumetry have been introduced, with the hope that such methods will be more accurate and consistent than currently used planar measures of size. However, the error associated with volume estimation methods still needs to be quantified. Volume estimation error is multi-faceted in the sense that there is variability associated with the patient, the software tool and the CT system. A primary goal of our current research efforts is to quantify the various sources of measurement error and, when possible, minimize their effects. In order to assess the bias of an estimate, the actual value, or "truth," must be known. In this work we investigate the reliability of micro CT to determine the "true" volume of synthetic nodules. The advantage of micro CT over other truthing methods is that it can provide both absolute volume and shape information in a single measurement. In the current study we compare micro CT volume truth to weight-density truth for spherical, elliptical, spiculated and lobulated nodules with diameters from 5 to 40 mm, and densities of -630 and +100 HU. The percent differences between micro CT and weight-density volume for -630 HU nodules range from [-21.7%, -0.6%] (mean= -11.9%) and the differences for +100 HU nodules range from [-0.9%, 3.0%] (mean=1.7%).

An experimental result of estimating an application volume by machine learning techniques.

PubMed

Hasegawa, Tatsuhito; Koshino, Makoto; Kimura, Haruhiko

2015-01-01

In this study, we improved the usability of smartphones by automating a user's operations. We developed an intelligent system using machine learning techniques that periodically detects a user's context on a smartphone. We selected the Android operating system because it has the largest market share and highest flexibility of its development environment. In this paper, we describe an application that automatically adjusts application volume. Adjusting the volume can be easily forgotten because users need to push the volume buttons to alter the volume depending on the given situation. Therefore, we developed an application that automatically adjusts the volume based on learned user settings. Application volume can be set differently from ringtone volume on Android devices, and these volume settings are associated with each specific application including games. Our application records a user's location, the volume setting, the foreground application name and other such attributes as learning data, thereby estimating whether the volume should be adjusted using machine learning techniques via Weka.

Penn Working Papers in Educational Linguistics, Volume 5, Number 2.

ERIC Educational Resources Information Center

Riley, Kathryn, Ed.

The working papers contained in this volume include the following: "Research on Language Learning; How Can It Respond to Classroom Concerns?" (Teresa Pica); "Building Rapport Through Indirect Complaints: Implications for Language Learning" (Diana Boxer); "(Bi)literacy and Empowerment: Education for Indigenous Groups in…

Acquisition Regulations and Offshore Software Development: Implications for Cybersecurity of DOD Networks

DTIC Science & Technology

2013-02-14

Kessler, “Protection and Protectionism: The Practicalities of Offshore Software Devleopment in Government Procurement,” Public Contract Law Journal, Volume...Protection and Protectionism: The Practicalities of Offshore Software Development In Government Procurement,” Public Contract Law Journal, Volume 38, No. 1

Empirical Research without Certainty

ERIC Educational Resources Information Center

Floden, Robert E.

2009-01-01

In this essay, Robert Floden reviews three recent volumes in the Philosophy, Theory, and Educational Research series that address the philosophical implications of three "isms"-- postpositivism, pragmatism, and poststructuralism--for empirical educational research. These volumes, written by D.C. Phillips, Gert J.J. Biesta, and Michael A. Peters,…

A sediment transport model for incision of gullies on steep topography

Treesearch

Erkan Istanbulluoglu; David G. Tarboton; Robert T. Pack; Charles H. Luce

2003-01-01

We have conducted surveys of gullies that developed in a small, steep watershed in the Idaho Batholith after a severe wildfire followed by intense precipitation. We measured gully length and cross sections to estimate the volumes of sediment loss due to gully formation. These volume estimates are assumed to provide an estimate of sediment transport capacity at each...

Illinois's Forest Resources in 2002.

Treesearch

Earl C. Leatherberry; Gary J Brand; Dick C Little

2004-01-01

Results of the 2002 annual inventory of Illinois shows an estimated 4.3 million acres of forest land. The estimate of total volume of all live trees on forest land is 7.5 billion cubic feet. Nearly 4.1 million acres of forest land are classified as timberland. The estimate of growing-stock volume on timberland is 6.3 billion cubic feet. All live aboveground tree...

Piezo1 links mechanical forces to red blood cell volume.

PubMed

Cahalan, Stuart M; Lukacs, Viktor; Ranade, Sanjeev S; Chien, Shu; Bandell, Michael; Patapoutian, Ardem

2015-05-22

Red blood cells (RBCs) experience significant mechanical forces while recirculating, but the consequences of these forces are not fully understood. Recent work has shown that gain-of-function mutations in mechanically activated Piezo1 cation channels are associated with the dehydrating RBC disease xerocytosis, implicating a role of mechanotransduction in RBC volume regulation. However, the mechanisms by which these mutations result in RBC dehydration are unknown. In this study, we show that RBCs exhibit robust calcium entry in response to mechanical stretch and that this entry is dependent on Piezo1 expression. Furthermore, RBCs from blood-cell-specific Piezo1 conditional knockout mice are overhydrated and exhibit increased fragility both in vitro and in vivo. Finally, we show that Yoda1, a chemical activator of Piezo1, causes calcium influx and subsequent dehydration of RBCs via downstream activation of the KCa3.1 Gardos channel, directly implicating Piezo1 signaling in RBC volume control. Therefore, mechanically activated Piezo1 plays an essential role in RBC volume homeostasis.

Stratigraphy of Oceanus Procellarum basalts - Sources and styles of emplacement

NASA Technical Reports Server (NTRS)

Whitford-Stark, J. L.; Head, J. W., III

1980-01-01

The basaltic fill of Oceanus Procellarum has been formally subdivided into four lithostratigraphic formations: The Repsold Formation, the Telemann Formation, the Hermann Formation, and the Sharp Formation. The Repsold Formation is composed of high-Ti basalts and pyroclastic deposits with an estimated age of 3.75 + or - 0.05 b.y. and an estimated volume of about 2.1 x 10 to the 5th cu km. This is overlain by the Telemann Formation composed of very low-Ti basalts and pyroclastic deposits with an estimated age of 3.6 + or - 0.2 b.y. and a volume of 4.2 x 10 to the 5th cu km. The Hermann Formation, composed of intermediate basalts with an estimated age of 3.3 + or - 0.3 b.y., represents the next youngest unit with an estimated volume of 2.2 x 10 to the 5th cu km. The youngest materials in Procellarum are the medium-to-high-Ti basalts comprising the Sharp Formation with an estimated age of 2.7 + or - 0.7 b.y. and a volume of 1.8 x 10 to the 4th cu km.

Alignment of training curriculum and surgical practice: implications for competency, manpower, and practice modeling.

PubMed

Sømme, S; Bronsert, M; Kempe, A; Morrato, E H; Ziegler, M

2012-02-01

The attractiveness of pediatric surgery (PS) as a specialty includes its primary role in the care of multisystemic disease. We were interested in identifying changes in operative case quality and quantity when comparing PS residents to PS practitioners. The 2006 Accreditation Council for Graduate Medical Education PS resident current procedural terminology (CPT) code database (26,077 resident cases) was merged with the 2006 Kids' Inpatient Database of International Classification of Diseases (ICD)-9 procedure codes (230,504 practitioner cases) and categorized by case type and volumes according to a resident CPT reference file. Cases were categorized into 84 procedure types. A recent estimate of 691 practicing pediatric surgeons was used as denominator to calculate case volume per surgeon. Our analysis focused on the PS index cases and we compared PS residents to subspecialty board certified general pediatric surgeons in practice. We excluded cases that may be performed by general surgeons without PS training. Our data indicate that, on average, 501 cases are performed annually by each PS resident. We identified significant differences in case volume per surgeon between training and practice for most PS index cases.CONCLUSIONS The PS index case quantity declined significantly from training to practice. If a volume to outcome relationship applies to these complex and infrequent PS cases, then to sustain and improve clinical quality post-training will require a new paradigm of continued learning. Additionally, a relook at the optimal manpower and more focused regionalization is warranted. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

The pack size effect: Influence on consumer perceptions of portion sizes.

PubMed

Hieke, Sophie; Palascha, Aikaterini; Jola, Corinne; Wills, Josephine; Raats, Monique M

2016-01-01

Larger portions as well as larger packs can lead to larger prospective consumption estimates, larger servings and increased consumption, described as 'portion-size effects' and 'pack size effects'. Although related, the effects of pack sizes on portion estimates have received less attention. While it is not possible to generalize consumer behaviour across cultures, external cues taken from pack size may affect us all. We thus examined whether pack sizes influence portion size estimates across cultures, leading to a general 'pack size effect'. We compared portion size estimates based on digital presentations of different product pack sizes of solid and liquid products. The study with 13,177 participants across six European countries consisted of three parts. Parts 1 and 2 asked participants to indicate the number of portions present in a combined photographic and text-based description of different pack sizes. The estimated portion size was calculated as the quotient of the content weight or volume of the food presented and the number of stated portions. In Part 3, participants stated the number of food items that make up a portion when presented with packs of food containing either a small or a large number of items. The estimated portion size was calculated as the item weight times the item number. For all three parts and across all countries, we found that participants' portion estimates were based on larger portions for larger packs compared to smaller packs (Part 1 and 2) as well as more items to make up a portion (Part 3); hence, portions were stated to be larger in all cases. Considering that the larger estimated portions are likely to be consumed, there are implications for energy intake and weight status. Copyright © 2015 Elsevier Ltd. All rights reserved.

Allometric Analysis Detects Brain Size-Independent Effects of Sex and Sex Chromosome Complement on Human Cerebellar Organization

PubMed Central

Mankiw, Catherine; Park, Min Tae M.; Reardon, P.K.; Fish, Ari M.; Clasen, Liv S.; Greenstein, Deanna; Blumenthal, Jonathan D.; Lerch, Jason P.; Chakravarty, M. Mallar

2017-01-01

The cerebellum is a large hindbrain structure that is increasingly recognized for its contribution to diverse domains of cognitive and affective processing in human health and disease. Although several of these domains are sex biased, our fundamental understanding of cerebellar sex differences—including their spatial distribution, potential biological determinants, and independence from brain volume variation—lags far behind that for the cerebrum. Here, we harness automated neuroimaging methods for cerebellar morphometrics in 417 individuals to (1) localize normative male–female differences in raw cerebellar volume, (2) compare these to sex chromosome effects estimated across five rare sex (X/Y) chromosome aneuploidy (SCA) syndromes, and (3) clarify brain size-independent effects of sex and SCA on cerebellar anatomy using a generalizable allometric approach that considers scaling relationships between regional cerebellar volume and brain volume in health. The integration of these approaches shows that (1) sex and SCA effects on raw cerebellar volume are large and distributed, but regionally heterogeneous, (2) human cerebellar volume scales with brain volume in a highly nonlinear and regionally heterogeneous fashion that departs from documented patterns of cerebellar scaling in phylogeny, and (3) cerebellar organization is modified in a brain size-independent manner by sex (relative expansion of total cerebellum, flocculus, and Crus II-lobule VIIIB volumes in males) and SCA (contraction of total cerebellar, lobule IV, and Crus I volumes with additional X- or Y-chromosomes; X-specific contraction of Crus II-lobule VIIIB). Our methods and results clarify the shifts in human cerebellar organization that accompany interwoven variations in sex, sex chromosome complement, and brain size. SIGNIFICANCE STATEMENT Cerebellar systems are implicated in diverse domains of sex-biased behavior and pathology, but we lack a basic understanding of how sex differences in the human cerebellum are distributed and determined. We leverage a rare neuroimaging dataset to deconvolve the interwoven effects of sex, sex chromosome complement, and brain size on human cerebellar organization. We reveal topographically variegated scaling relationships between regional cerebellar volume and brain size in humans, which (1) are distinct from those observed in phylogeny, (2) invalidate a traditional neuroimaging method for brain volume correction, and (3) allow more valid and accurate resolution of which cerebellar subcomponents are sensitive to sex and sex chromosome complement. These findings advance understanding of cerebellar organization in health and sex chromosome aneuploidy. PMID:28314818

FACTORS IMPLICATED IN AMPHIBIAN POPULATION DECLINES IN THE UNITED STATES

EPA Science Inventory

Factors adversely affecting amphibian populations in the US were evaluated using information from species accounts written in a standardized format by multiple authors (Volume 2 of this book). For each species, factors implicated by the authors (i.e., known or suspected) as affec...

Trends in Transforming Scholarly Communication and Their Implications.

ERIC Educational Resources Information Center

Liu, Ziming

2003-01-01

Explores trends in transforming scholarly publishing and possible implications for electronic publishing and digital libraries. Topics include changes in collaborative research; changes in volume of information production; and age of cited documents and how older documents are used in today's network environment. (Author/LRW)

Validation of a White-light 3D Body Volume Scanner to Assess Body Composition.

PubMed

Medina-Inojosa, Jose; Somers, Virend; Jenkins, Sarah; Zundel, Jennifer; Johnson, Lynne; Grimes, Chassidy; Lopez-Jimenez, Francisco

2017-01-01

Estimating body fat content has shown to be a better predictor of adiposity-related cardiovascular risk than the commonly used body mass index (BMI). The white-light 3D body volume index (BVI) scanner is a non-invasive device normally used in the clothing industry to assess body shapes and sizes. We assessed the hypothesis that volume obtained by BVI is comparable to the volume obtained by air displacement plethysmography (Bod-Pod) and thus capable of assessing body fat mass using the bi-compartmental principles of body composition. We compared BVI to Bod-pod, a validated bicompartmental method to assess body fat percent that uses pressure/volume relationships in isothermal conditions to estimate body volume. Volume is then used to calculate body density (BD) applying the formula density=Body Mass/Volume. Body fat mass percentage is then calculated using the Siri formula (4.95/BD - 4.50) × 100. Subjects were undergoing a wellness evaluation. Measurements from both devices were obtained the same day. A prediction model for total Bod-pod volume was developed using linear regression based on 80% of the observations (N=971), as follows: Predicted Bod-pod Volume (L)=9.498+0.805*(BVI volume, L)-0.0411*(Age, years)-3.295*(Male=0, Female=1)+0.0554*(BVI volume, L)*(Male=0, Female=1)+0.0282*(Age, years)*(Male=0, Female=1). Predictions for Bod-pod volume based on the estimated model were then calculated for the remaining 20% (N=243) and compared to the volume measured by the Bod-pod. Mean age among the 971 individuals was 41.5 ± 12.9 years, 39.4% were men, weight 81.6 ± 20.9 kg, BMI was 27.8 ± 6.3kg/m 2 . Average difference between volume measured by Bod-pod- predicted volume by BVI was 0.0 L, median: -0.4 L, IQR: -1.8 L to 1.5 L, R2=0.9845. Average difference between body fat measured-predicted was-1%, median: -2.7%, IQR: -13.2 to 9.9, R2=0.9236. Volume and BFM can be estimated by using volume measurements obtained by a white- light 3D body scanner and the prediction model developed in this study.

Implication of seismic attenuation for gas hydrate resource characterization, Mallik, Mackenzie Delta, Canada

NASA Astrophysics Data System (ADS)

Bellefleur, G.; Riedel, M.; Brent, T.; Wright, F.; Dallimore, S. R.

2007-10-01

Wave attenuation is an important physical property of hydrate-bearing sediments that is rarely taken into account in site characterization with seismic data. We present a field example showing improved images of hydrate-bearing sediments on seismic data after compensation of attenuation effects. Compressional quality factors estimated from zero-offset Vertical Seismic Profiling data acquired at Mallik, Northwest Territories, Canada, demonstrate significant wave attenuation for hydrate-bearing sediments. These results are in agreement with previous attenuation estimates obtained from sonic logs and crosshole data at different frequency intervals. The application of an inverse Q-filter to compensate attenuation effects of permafrost and hydrate-bearing sediments improved the resolution of surface 3D seismic data and its correlation with log data, particularly for the shallowest gas hydrate interval. Compensation of the attenuation effects of the permafrost likely explains most of the improvements for the shallow gas hydrate zone. Our results show that characterization of the Mallik gas hydrates with seismic data not corrected for attenuation would tend to overestimate thicknesses and lateral extent of hydrate-bearing strata and hence, the volume of hydrates in place.

Groundwater withdrawal in the Central Valley, California: implications for San Andreas Fault stressing and lithosphere rheology

NASA Astrophysics Data System (ADS)

Lundgren, P.; Liu, Z.; Ali, S. T.; Farr, T.; Faunt, C. C.

2016-12-01

Anthropogenic perturbations to crustal loading due to groundwater pumping are increasingly recognized as causing changes in nearby fault stresses. We present preliminary analysis of crustal unloading in the Central Valley (CV), California, for the period 2006-2010 to infer Coulomb stress changes on the central San Andreas Fault (CSAF), lithospheric rheology, and system memory due to more than a century of groundwater withdrawal in the southern CV. We use data-driven unloading estimates to drive three-dimensional (3-D) finite element method models and compare model vertical surface deformation rates with observed GPS uplift rates outside the CV. Groundwater level changes are observed through well water elevation changes and through the resultant surface deformation (subsidence) by interferometric synthetic aperture radar (InSAR) and through broader scale changes in gravity from the GRACE satellite time variable gravity data [Famiglietti et al., 2011] that constrain the overall water volume changes. Combining InSAR with well-water data we are able to estimate the aquifer skeletal elastic and inelastic response and through a linear inversion derive the water volume (load) changes across the Central Valley and compare them with GRACE-inferred groundwater changes. Preliminary 3-D finite element method modeling that considers elastic and viscosity structure in the lithosphere gives three interesting results: 1) elastic models poorly fit the uplift rates near the SAF; 2) viscoelastic models that simulate different unloading histories show the past history of groundwater unloading has significant residual uplift rates and fault stress changes; 3) Coulomb stress change varies from inhibited on the locked (Carrizo) section to promoted on the creeping section of the SAF north of Parkfield. Thus, 3D models that account for lithosphere rheology, loading history viscous relaxation, have significant implications for longer-term time-dependent deformation, stress perturbation, and earthquake hazard on the nearby faults. Reference: Famiglietti, J. S., M. Lo, S. L. Ho, J. Bethune, K. J. Anderson, T. H. Syed, S. C. Swenson, C. R. de Linage, and M. Rodell, 2011, Satellites measure recent rates of groundwater depletion in California's Central Valley, Geophys. Res. Lett., 38, L03403, doi:10.1029/2010GL046442.

Pineal Gland Volume Assessed by MRI and Its Correlation with 6-Sulfatoxymelatonin Levels among Older Men.

PubMed

Sigurdardottir, Lara G; Markt, Sarah C; Sigurdsson, Sigurdur; Aspelund, Thor; Fall, Katja; Schernhammer, Eva; Rider, Jennifer R; Launer, Lenore; Harris, Tamara; Stampfer, Meir J; Gudnason, Vilmundur; Czeisler, Charles A; Lockley, Steven W; Valdimarsdottir, Unnur A; Mucci, Lorelei A

2016-10-01

The pineal gland produces the hormone melatonin, and its volume may influence melatonin levels. We describe an innovative method for estimating pineal volume in humans and present the association of pineal parenchyma volume with levels of the primary melatonin metabolite, 6-sulfatoxymelatonin. We selected a random sample of 122 older Icelandic men nested within the AGES-Reykjavik cohort and measured their total pineal volume, their parenchyma volume, and the extent of calcification and cysts. For volume estimations we used manual segmentation of magnetic resonance images in the axial plane with simultaneous side-by-side view of the sagittal and coronal plane. We used multivariable adjusted linear regression models to estimate the association of pineal parenchyma volume and baseline characteristics, including 6-sulfatoxymelatonin levels. We used logistic regression to test for differences in first morning urinary 6-sulfatoxymelatonin levels among men with or without cystic or calcified glands. The pineal glands varied in volume, shape, and composition. Cysts were present in 59% of the glands and calcifications in 21%. The mean total pineal volume measured 207 mm(3) (range 65-536 mm(3)) and parenchyma volume 178 mm(3) (range 65-503 mm(3)). In multivariable-adjusted models, pineal parenchyma volume was positively correlated with 6-sulfatoxymelatonin levels (β = 0.52, p < 0.001). Levels of 6-sulfatoxymelatonin did not differ significantly by presence of cysts or calcification. By using an innovative method for pineal assessment, we found pineal parenchyma volume to be positively correlated with 6-sulfatoxymelatonin levels, in line with other recent studies. © 2016 The Author(s).

Pineal Gland Volume Assessed by MRI and its Correlation with 6-Sulfatoxymelatonin Levels among Older Men

PubMed Central

Sigurdardottir, Lara G.; Markt, Sarah C.; Sigurdsson, Sigurdur; Aspelund, Thor; Fall, Katja; Schernhammer, Eva; Rider, Jennifer R.; Launer, Lenore; Harris, Tamara; Stampfer, Meir J.; Gudnason, Vilmundur; Czeisler, Charles A.; Lockley, Steven W.; Valdimarsdottir, Unnur A.; Mucci, Lorelei A.

2017-01-01

The pineal gland produces the hormone melatonin and its volume may influence melatonin levels. We describe an innovative method for estimating pineal volume in humans and present the association of pineal parenchyma volume with levels of the primary melatonin metabolite, 6-sulfatoxymelatonin. We selected a random sample of 122 older Icelandic men nested within the AGES-Reykjavik cohort and measured their total pineal volume, parenchyma volume, and the extent of calcification and cysts. For volume estimations we used manual segmentation of MR images in the axial plane with simultaneous side-by-side view of the sagittal and coronal plane. We used multivariable adjusted linear regression models to estimate the association of pineal parenchyma volume and baseline characteristics, including 6-sulfatoxymelatonin levels. We used logistic regression to test for differences in first morning urinary 6-sulfatoxymelatonin levels among men with or without cystic or calcified glands. The pineal glands varied in volume, shape and composition. Cysts were present in 59% of the glands and calcifications in 21%. The mean total pineal volume measured 207 mm3 (range 65–536 mm3) and parenchyma volume 178 mm3 (range 65–503 mm3). In multivariable-adjusted models pineal parenchyma volume was positively correlated with 6-sulfatoxymelatonin levels (β=0.52, p<0.001). 6-sulfatoxymelatonin levels did not differ significantly by presence of cysts or calcification. By using an innovative method for pineal assessment we found pineal parenchyma volume to be positively correlated with 6-sulfatoxymelatonin levels, in line with other recent studies. PMID:27449477

Radar volume reflectivity estimation using an array of ground-based rainfall drop size detectors

NASA Astrophysics Data System (ADS)

Lane, John; Merceret, Francis; Kasparis, Takis; Roy, D.; Muller, Brad; Jones, W. Linwood

2000-08-01

Rainfall drop size distribution (DSD) measurements made by single disdrometers at isolated ground sites have traditionally been used to estimate the transformation between weather radar reflectivity Z and rainfall rate R. Despite the immense disparity in sampling geometries, the resulting Z-R relation obtained by these single point measurements has historically been important in the study of applied radar meteorology. Simultaneous DSD measurements made at several ground sites within a microscale area may be used to improve the estimate of radar reflectivity in the air volume surrounding the disdrometer array. By applying the equations of motion for non-interacting hydrometers, a volume estimate of Z is obtained from the array of ground based disdrometers by first calculating a 3D drop size distribution. The 3D-DSD model assumes that only gravity and terminal velocity due to atmospheric drag within the sampling volume influence hydrometer dynamics. The sampling volume is characterized by wind velocities, which are input parameters to the 3D-DSD model, composed of vertical and horizontal components. Reflectivity data from four consecutive WSR-88D volume scans, acquired during a thunderstorm near Melbourne, FL on June 1, 1997, are compared to data processed using the 3D-DSD model and data form three ground based disdrometers of a microscale array.

Bidirectional segmentation of prostate capsule from ultrasound volumes: an improved strategy

NASA Astrophysics Data System (ADS)

Wei, Liyang; Narayanan, Ramkrishnan; Kumar, Dinesh; Fenster, Aaron; Barqawi, Albaha; Werahera, Priya; Crawford, E. David; Suri, Jasjit S.

2008-03-01

Prostate volume is an indirect indicator for several prostate diseases. Volume estimation is a desired requirement during prostate biopsy, therapy and clinical follow up. Image segmentation is thus necessary. Previously, discrete dynamic contour (DDC) was implemented in orthogonal unidirectional on the slice-by-slice basis for prostate boundary estimation. This suffered from the glitch that it needed stopping criteria during the propagation of segmentation procedure from slice-to-slice. To overcome this glitch, axial DDC was implemented and this suffered from the fact that central axis never remains fixed and wobbles during propagation of segmentation from slice-to-slice. The effect of this was a multi-fold reconstructed surface. This paper presents a bidirectional DDC approach, thereby removing the two glitches. Our bidirectional DDC protocol was tested on a clinical dataset on 28 3-D ultrasound image volumes acquired using side fire Philips transrectal ultrasound. We demonstrate the orthogonal bidirectional DDC strategy achieved the most accurate volume estimation compared with previously published orthogonal unidirectional DDC and axial DDC methods. Compared to the ground truth, we show that the mean volume estimation errors were: 18.48%, 9.21% and 7.82% for unidirectional, axial and bidirectional DDC methods, respectively. The segmentation architecture is implemented in Visual C++ in Windows environment.

Revitalizing Higher Education. Issues in Higher Education, Volume 3. First Edition.

ERIC Educational Resources Information Center

Salmi, Jamil, Ed.; Verspoor, Adriaan M., Ed.

This volume contains 13 papers on experiences with reform and innovation in higher education and their implications for developing countries. Four themes are highlighted: higher education and development, performance assessment, sustainable financing, and effectiveness in governance and management. The papers include: "Introduction:…

Universal Child Immunization by 1990.

ERIC Educational Resources Information Center

Mandl, P. E., Ed.

1985-01-01

The present volume endeavors to highlight the deeper significance and broader implications for development theory, policy and practice of the realization of the movement toward universal child immunization by 1990 (UCI-1990). Simultaneously, the volume collects and analyzes the most significant findings and experiences of the movement since 1984.…

Topics in Culture Learning, Volume 5.

ERIC Educational Resources Information Center

Brislin, Richard W., Ed.; Hamnett, Michael P., Ed.

The first section of this volume includes articles on cross-cultural teaching: "Mau Piailug's Navigation of Hokule'a from Hawaii to Tahiti," by David Lewis; "The New World Order and the Globalization of Social Science: Some Implications for Teaching Cross-Culturally," by Amarjit Singh; "Ponape: Cross-Cultural Contact,…

Gravity Recovery and Climate Experiment (GRACE) detection of water storage changes in the Three Gorges Reservoir of China and comparison with in situ measurements

NASA Astrophysics Data System (ADS)

Wang, Xianwei; de Linage, Caroline; Famiglietti, James; Zender, Charles S.

2011-12-01

Water impoundment in the Three Gorges Reservoir (TGR) of China caused a large mass redistribution from the oceans to a concentrated land area in a short time period. We show that this mass shift is captured by the Gravity Recovery and Climate Experiment (GRACE) unconstrained global solutions at a 400 km spatial resolution after removing correlated errors. The WaterGAP Global Hydrology Model (WGHM) is selected to isolate the TGR contribution from regional water storage changes. For the first time, this study compares the GRACE (minus WGHM) estimated TGR volume changes with in situ measurements from April 2002 to May 2010 at a monthly time scale. During the 8 year study period, GRACE-WGHM estimated TGR volume changes show an increasing trend consistent with the TGR in situ measurements and lead to similar estimates of impounded water volume. GRACE-WGHM estimated total volume increase agrees to within 14% (3.2 km3) of the in situ measurements. This indicates that GRACE can retrieve the true amplitudes of large surface water storage changes in a concentrated area that is much smaller than the spatial resolution of its global harmonic solutions. The GRACE-WGHM estimated TGR monthly volume changes explain 76% (r2 = 0.76) of in situ measurement monthly variability and have an uncertainty of 4.62 km3. Our results also indicate reservoir leakage and groundwater recharge due to TGR filling and contamination from neighboring lakes are nonnegligible in the GRACE total water storage changes. Moreover, GRACE observations could provide a relatively accurate estimate of global water volume withheld by newly constructed large reservoirs and their impacts on global sea level rise since 2002.

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

USGS Publications Warehouse

Nadeau, Christopher P.; Conway, Courtney J.

2012-01-01

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

Estimating stem volume and biomass of Pinus koraiensis using LiDAR data.

PubMed

Kwak, Doo-Ahn; Lee, Woo-Kyun; Cho, Hyun-Kook; Lee, Seung-Ho; Son, Yowhan; Kafatos, Menas; Kim, So-Ra

2010-07-01

The objective of this study was to estimate the stem volume and biomass of individual trees using the crown geometric volume (CGV), which was extracted from small-footprint light detection and ranging (LiDAR) data. Attempts were made to analyze the stem volume and biomass of Korean Pine stands (Pinus koraiensis Sieb. et Zucc.) for three classes of tree density: low (240 N/ha), medium (370 N/ha), and high (1,340 N/ha). To delineate individual trees, extended maxima transformation and watershed segmentation of image processing methods were applied, as in one of our previous studies. As the next step, the crown base height (CBH) of individual trees has to be determined; information for this was found in the LiDAR point cloud data using k-means clustering. The LiDAR-derived CGV and stem volume can be estimated on the basis of the proportional relationship between the CGV and stem volume. As a result, low tree-density plots had the best performance for LiDAR-derived CBH, CGV, and stem volume (R (2) = 0.67, 0.57, and 0.68, respectively) and accuracy was lowest for high tree-density plots (R (2) = 0.48, 0.36, and 0.44, respectively). In the case of medium tree-density plots accuracy was R (2) = 0.51, 0.52, and 0.62, respectively. The LiDAR-derived stem biomass can be predicted from the stem volume using the wood basic density of coniferous trees (0.48 g/cm(3)), and the LiDAR-derived above-ground biomass can then be estimated from the stem volume using the biomass conversion and expansion factors (BCEF, 1.29) proposed by the Korea Forest Research Institute (KFRI).

From field data to volumes: constraining uncertainties in pyroclastic eruption parameters

USGS Publications Warehouse

Klawonn, Malin; Houghton, Bruce F.; Swanson, Don; Fagents, Sarah A.; Wessel, Paul; Wolfe, Cecily J.

2014-01-01

In this study, we aim to understand the variability in eruption volume estimates derived from field studies of pyroclastic deposits. We distributed paper maps of the 1959 Kīlauea Iki tephra to 101 volcanologists worldwide, who produced hand-drawn isopachs. Across the returned maps, uncertainty in isopach areas is 7 % across the well-sampled deposit but increases to over 30 % for isopachs that are governed by the largest and smallest thickness measurements. We fit the exponential, power-law, and Weibull functions through the isopach thickness versus area1/2 values and find volume estimate variations up to a factor of 4.9 for a single map. Across all maps and methodologies, we find an average standard deviation for a total volume of s = 29 %. The volume uncertainties are largest for the most proximal (s = 62 %) and distal field (s = 53 %) and small for the densely sampled intermediate deposit (s = 8 %). For the Kīlauea Iki 1959 eruption, we find that the deposit beyond the 5-cm isopach contains only 2 % of the total erupted volume, whereas the near-source deposit contains 48 % and the intermediate deposit 50 % of the total volume. Thus, the relative uncertainty within each zone impacts the total volume estimates differently. The observed uncertainties for the different deposit regions in this study illustrate a fundamental problem of estimating eruption volumes: while some methodologies may provide better fits to the isopach data or rely on fewer free parameters, the main issue remains the predictive capabilities of the empirical functions for the regions where measurements are missing.

Validation of Test Weighing Protocol to Estimate Enteral Feeding Volumes in Preterm Infants.

PubMed

Rankin, Michael W; Jimenez, Elizabeth Yakes; Caraco, Marina; Collinson, Marie; Lostetter, Lisa; DuPont, Tara L

2016-11-01

To evaluate the accuracy of pre- and postfeeding weights to estimate enteral feeding volumes in preterm infants. Single-center prospective cohort study of infants 28-36 weeks' corrected age receiving gavage feedings. For each test weight, 3 pre- and 3 postgavage feeding weights were obtained by study personnel, blinded to feeding volume, via a specific protocol. The correlation between test weight difference and actual volume ingested was assessed by the use of summary statistics, Spearman rho, and graphical analyses. The relationship between categorical predictive variables and a predefined acceptable difference (±5 mL) was assessed with the χ 2 or Fisher exact test. A total of 101 test weights were performed in 68 infants. Estimated and actual feeding volumes were highly correlated (r = 0.94, P < .001), with a mean absolute difference of 2.95 mL (SD: 2.70; range: 0, 12.3 mL; 5th, 95th percentile: 0, 9.3); 85% of test weights were within ±5 mL of actual feeding volume and did not vary significantly by corrected age, feeding tube or respiratory support type, feeding duration or volume, formula vs breast milk, or caloric density. With adherence to study protocol, 89% of test weights (66/74) were within ±5 mL of actual volume, compared with 71% (19/27, P = .04) when concerns about protocol adherence were noted (eg, difficulty securing oxygen tubing). Via the use of a standard protocol, feeding volumes can be estimated accurately by pre- and postfeeding weights. Test weighing could be a valuable tool to support direct breastfeeding in the neonatal intensive care unit. Copyright © 2016 Elsevier Inc. All rights reserved.

Efficiency and precision for estimating timber and non-timber attributes using Landsat-based stratification methods in two-phase sampling in northwest California

Treesearch

Antti T. Kaartinen; Jeremy S. Fried; Paul A. Dunham

2002-01-01

Three Landsat TM-based GIS layers were evaluated as alternatives to conventional, photointerpretation-based stratification of FIA field plots. Estimates for timberland area, timber volume, and volume of down wood were calculated for California's North Coast Survey Unit of 2.5 million hectares. The estimates were compared on the basis of standard errors,...

Iowa's forest resources in 2002.

Treesearch

Earl C Leatherberry; Gary J. Brand

2004-01-01

Results of the 2002 annual inventory of Iowa show an estimated 2.7 million acres of forest land. The estimate of total all live tree volume on forest land is 3.9 billion cubic feet. Nearly 2.6 million acres of forest land in Iowa are classified as timberland. The estimate of growing-stock volume on timberland is 3.0 billion cubic feet. All live aboveground tree biomass...

Iowa's forest resources in 2001

Treesearch

Earl C. Leatherberry; Steve Pennington; Gary J. Brand

2003-01-01

Results of the 2001 annual inventory of Iowa show an estimated 2.6 million acres of forest land in the State. The estimate of total all live tree volume on forest land is 3.6 billion cubic feet. Nearly 2.5 million acres of forest land in Iowa are classified as timberland. The estimate of growing-stock volume on timberland is 2.7 billion cubic feet. All live aboveground...

Estimation on the First Cycle of the Annual Forest Inventory System: Methods, Preliminary Results, and Observations

Treesearch

Mark H. Hansen; Gary J. Brand; Daniel G. Wendt; Ronald E. McRoberts

2001-01-01

The first year of annual FIA data collection in the North Central region was completed for 1999 in Indiana, Iowa, Minnesota, and Missouri. Estimates of timberland area, total growing-stock volume and growing-stock volume per acre are presented. These estimates are based on data from 1 year, collected at the base Federal inventory intensity, a lower intensity sample...

Hippocampal MR volumetry

NASA Astrophysics Data System (ADS)

Haller, John W.; Botteron, K.; Brunsden, Barry S.; Sheline, Yvette I.; Walkup, Ronald K.; Black, Kevin J.; Gado, Mokhtar; Vannier, Michael W.

1994-09-01

Goal: To estimate hippocampal volumes from in vivo 3D magnetic resonance (MR) brain images and determine inter-rater and intra- rater repeatability. Objective: The precision and repeatability of hippocampal volume estimates using stereologic measurement methods is sought. Design: Five normal control and five schizophrenic subjects were MR scanned using a MPRAGE protocol. Fixed grid stereologic methods were used to estimate hippocampal volumes on a graphics workstation. The images were preprocessed using histogram analysis to standardize 3D MR image scaling from 16 to 8 bits and image volumes were interpolated to 0.5 mm3 isotropic voxels. The following variables were constant for the repeated stereologic measures: grid size, inter-slice distance (1.5 mm), voxel dimensions (0.5 mm3), number of hippocampi measured (10), total number of measurements per rater (40), and number of raters (5). Two grid sizes were tested to determine the coefficient of error associated with the number of sampled 'hits' (approximately 140 and 280) on the hippocampus. Starting slice and grid position were randomly varied to assure unbiased volume estimates. Raters were blind to subject identity, diagnosis, and side of the brain from which the image volumes were extracted and the order of subject presentation was randomized for each of the raters. Inter- and intra-rater intraclass correlation coefficients (ICC) were determined. Results: The data indicate excellent repeatability of fixed grid stereologic hippocampal volume measures when using an inter-slice distance of 1.5 mm and a 6.25 mm2 grid (inter-rater ICCs equals 0.86 - 0.97, intra- rater ICCs equals 0.85 - 0.97). One major advantage of the current study was the use of 3D MR data which significantly improved visualization of hippocampal boundaries by providing the ability to access simultaneous orthogonal views while counting stereological marks within the hippocampus. Conclusion: Stereological estimates of 3D volumes from 2D MR sections provide an inexpensive, unbiased and efficient way of determining brain structural volumes. The high precision and repeatability demonstrated with stereological MR volumetry suggest that these methods may be efficiently used to measure small volume reductions associated with schizophrenia and other brain disorders.

A proposed framework for consensus-based lung tumour volume auto-segmentation in 4D computed tomography imaging

NASA Astrophysics Data System (ADS)

Martin, Spencer; Brophy, Mark; Palma, David; Louie, Alexander V.; Yu, Edward; Yaremko, Brian; Ahmad, Belal; Barron, John L.; Beauchemin, Steven S.; Rodrigues, George; Gaede, Stewart

2015-02-01

This work aims to propose and validate a framework for tumour volume auto-segmentation based on ground-truth estimates derived from multi-physician input contours to expedite 4D-CT based lung tumour volume delineation. 4D-CT datasets of ten non-small cell lung cancer (NSCLC) patients were manually segmented by 6 physicians. Multi-expert ground truth (GT) estimates were constructed using the STAPLE algorithm for the gross tumour volume (GTV) on all respiratory phases. Next, using a deformable model-based method, multi-expert GT on each individual phase of the 4D-CT dataset was propagated to all other phases providing auto-segmented GTVs and motion encompassing internal gross target volumes (IGTVs) based on GT estimates (STAPLE) from each respiratory phase of the 4D-CT dataset. Accuracy assessment of auto-segmentation employed graph cuts for 3D-shape reconstruction and point-set registration-based analysis yielding volumetric and distance-based measures. STAPLE-based auto-segmented GTV accuracy ranged from (81.51  ±  1.92) to (97.27  ±  0.28)% volumetric overlap of the estimated ground truth. IGTV auto-segmentation showed significantly improved accuracies with reduced variance for all patients ranging from 90.87 to 98.57% volumetric overlap of the ground truth volume. Additional metrics supported these observations with statistical significance. Accuracy of auto-segmentation was shown to be largely independent of selection of the initial propagation phase. IGTV construction based on auto-segmented GTVs within the 4D-CT dataset provided accurate and reliable target volumes compared to manual segmentation-based GT estimates. While inter-/intra-observer effects were largely mitigated, the proposed segmentation workflow is more complex than that of current clinical practice and requires further development.

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

Slater, Paul B.

Paralleling our recent computationally intensive (quasi-Monte Carlo) work for the case N=4 (e-print quant-ph/0308037), we undertake the task for N=6 of computing to high numerical accuracy, the formulas of Sommers and Zyczkowski (e-print quant-ph/0304041) for the (N{sup 2}-1)-dimensional volume and (N{sup 2}-2)-dimensional hyperarea of the (separable and nonseparable) NxN density matrices, based on the Bures (minimal monotone) metric--and also their analogous formulas (e-print quant-ph/0302197) for the (nonmonotone) flat Hilbert-Schmidt metric. With the same seven 10{sup 9} well-distributed ('low-discrepancy') sample points, we estimate the unknown volumes and hyperareas based on five additional (monotone) metrics of interest, including the Kubo-Mori and Wigner-Yanase.more » Further, we estimate all of these seven volume and seven hyperarea (unknown) quantities when restricted to the separable density matrices. The ratios of separable volumes (hyperareas) to separable plus nonseparable volumes (hyperareas) yield estimates of the separability probabilities of generically rank-6 (rank-5) density matrices. The (rank-6) separability probabilities obtained based on the 35-dimensional volumes appear to be--independently of the metric (each of the seven inducing Haar measure) employed--twice as large as those (rank-5 ones) based on the 34-dimensional hyperareas. (An additional estimate--33.9982--of the ratio of the rank-6 Hilbert-Schmidt separability probability to the rank-4 one is quite clearly close to integral too.) The doubling relationship also appears to hold for the N=4 case for the Hilbert-Schmidt metric, but not the others. We fit simple exact formulas to our estimates of the Hilbert-Schmidt separable volumes and hyperareas in both the N=4 and N=6 cases.« less

A proposed framework for consensus-based lung tumour volume auto-segmentation in 4D computed tomography imaging.

PubMed

Martin, Spencer; Brophy, Mark; Palma, David; Louie, Alexander V; Yu, Edward; Yaremko, Brian; Ahmad, Belal; Barron, John L; Beauchemin, Steven S; Rodrigues, George; Gaede, Stewart

2015-02-21

This work aims to propose and validate a framework for tumour volume auto-segmentation based on ground-truth estimates derived from multi-physician input contours to expedite 4D-CT based lung tumour volume delineation. 4D-CT datasets of ten non-small cell lung cancer (NSCLC) patients were manually segmented by 6 physicians. Multi-expert ground truth (GT) estimates were constructed using the STAPLE algorithm for the gross tumour volume (GTV) on all respiratory phases. Next, using a deformable model-based method, multi-expert GT on each individual phase of the 4D-CT dataset was propagated to all other phases providing auto-segmented GTVs and motion encompassing internal gross target volumes (IGTVs) based on GT estimates (STAPLE) from each respiratory phase of the 4D-CT dataset. Accuracy assessment of auto-segmentation employed graph cuts for 3D-shape reconstruction and point-set registration-based analysis yielding volumetric and distance-based measures. STAPLE-based auto-segmented GTV accuracy ranged from (81.51  ±  1.92) to (97.27  ±  0.28)% volumetric overlap of the estimated ground truth. IGTV auto-segmentation showed significantly improved accuracies with reduced variance for all patients ranging from 90.87 to 98.57% volumetric overlap of the ground truth volume. Additional metrics supported these observations with statistical significance. Accuracy of auto-segmentation was shown to be largely independent of selection of the initial propagation phase. IGTV construction based on auto-segmented GTVs within the 4D-CT dataset provided accurate and reliable target volumes compared to manual segmentation-based GT estimates. While inter-/intra-observer effects were largely mitigated, the proposed segmentation workflow is more complex than that of current clinical practice and requires further development.

Accuracy and feasibility of estimated tumour volumetry in primary gastric gastrointestinal stromal tumours: validation using semiautomated technique in 127 patients.

PubMed

Tirumani, Sree Harsha; Shinagare, Atul B; O'Neill, Ailbhe C; Nishino, Mizuki; Rosenthal, Michael H; Ramaiya, Nikhil H

2016-01-01

To validate estimated tumour volumetry in primary gastric gastrointestinal stromal tumours (GISTs) using semiautomated volumetry. In this IRB-approved retrospective study, we measured the three longest diameters in x, y, z axes on CTs of primary gastric GISTs in 127 consecutive patients (52 women, 75 men, mean age 61 years) at our institute between 2000 and 2013. Segmented volumes (Vsegmented) were obtained using commercial software by two radiologists. Estimate volumes (V1-V6) were obtained using formulae for spheres and ellipsoids. Intra- and interobserver agreement of Vsegmented and agreement of V1-6 with Vsegmented were analysed with concordance correlation coefficients (CCC) and Bland-Altman plots. Median Vsegmented and V1-V6 were 75.9, 124.9, 111.6, 94.0, 94.4, 61.7 and 80.3 cm(3), respectively. There was strong intra- and interobserver agreement for Vsegmented. Agreement with Vsegmented was highest for V6 (scalene ellipsoid, x ≠ y ≠ z), with CCC of 0.96 [95 % CI 0.95-0.97]. Mean relative difference was smallest for V6 (0.6 %), while it was -19.1 % for V5, +14.5 % for V4, +17.9 % for V3, +32.6 % for V2 and +47 % for V1. Ellipsoidal approximations of volume using three measured axes may be used to closely estimate Vsegmented when semiautomated techniques are unavailable. Estimation of tumour volume in primary GIST using mathematical formulae is feasible. Gastric GISTs are rarely spherical. Segmented volumes are highly concordant with three axis-based scalene ellipsoid volumes. Ellipsoid volume can be used as an alternative for automated tumour volumetry.

Topology of genetic associations between regional gray matter volume and intellectual ability: Evidence for a high capacity network.

PubMed

Bohlken, Marc M; Brouwer, Rachel M; Mandl, René C W; Hedman, Anna M; van den Heuvel, Martijn P; van Haren, Neeltje E M; Kahn, René S; Hulshoff Pol, Hilleke E

2016-01-01

Intelligence is associated with a network of distributed gray matter areas including the frontal and parietal higher association cortices and primary processing areas of the temporal and occipital lobes. Efficient information transfer between gray matter regions implicated in intelligence is thought to be critical for this trait to emerge. Genetic factors implicated in intelligence and gray matter may promote a high capacity for information transfer. Whether these genetic factors act globally or on local gray matter areas separately is not known. Brain maps of phenotypic and genetic associations between gray matter volume and intelligence were made using structural equation modeling of 3T MRI T1-weighted scans acquired in 167 adult twins of the newly acquired U-TWIN cohort. Subsequently, structural connectivity analyses (DTI) were performed to test the hypothesis that gray matter regions associated with intellectual ability form a densely connected core. Gray matter regions associated with intellectual ability were situated in the right prefrontal, bilateral temporal, bilateral parietal, right occipital and subcortical regions. Regions implicated in intelligence had high structural connectivity density compared to 10,000 reference networks (p=0.031). The genetic association with intelligence was for 39% explained by a genetic source unique to these regions (independent of total brain volume), this source specifically implicated the right supramarginal gyrus. Using a twin design, we show that intelligence is genetically represented in a spatially distributed and densely connected network of gray matter regions providing a high capacity infrastructure. Although genes for intelligence have overlap with those for total brain volume, we present evidence that there are genes for intelligence that act specifically on the subset of brain areas that form an efficient brain network. Copyright © 2015 Elsevier Inc. All rights reserved.

Implications of seed size for seedling survival in Carnegiea gigantea and Ferocactus wislizeni (Cactaceae)

USGS Publications Warehouse

Bowers, Janice E.; Pierson, E.A.

2001-01-01

Larger seeds have been shown to convey benefits for seedling survival but the mechanisms of this process are not well understood. In this study, seed size and seedling survival were compared for 2 sympatric cactus species, Carnegiea gigantea (Engelm.) Britt. & Rose and Ferocactus wislizeni (Engelm.) Britt. & Rose, in laboratory and field experiments in the northern Sonoran Desert. Both species have small seeds, but Ferocactus seeds are nearly twice as long and 3 times as heavy as those of Carnegiea. The difference in size is perpetuated after germination: new Ferocactus seedlings have 4 times the estimated volume of new Carnegiea seedlings. In an outdoor experiment, annual survivorship of both species was low but was 6 times higher for Ferocactus (6 seedlings, 8.1%) than Carnegiea (1 seedling, 1.4%). The pattern of seedling mortality in relation to temperature and rain suggests that, after the initial flush of seed and seedling predation, drought and heat took a greater toll on Carnegiea than Ferocactus seedlings, probably because the larger seedling volume of Ferocactus conferred greater drought tolerance. In addition, F. wislizeni could become established without benefit of nurse plants whereas C. gigantea could not; this might reflect differential tolerance to high soil temperatures.

The physical basis of glacier volume-area scaling

USGS Publications Warehouse

Bahr, D.B.; Meier, M.F.; Peckham, S.D.

1997-01-01

Ice volumes are known for only a few of the roughly 160,000 glaciers worldwide but are important components of many climate and sea level studies which require water flux estimates. A scaling analysis of the mass and momentum conservation equations shows that glacier volumes can be related by a power law to more easily observed glacier surface areas. The relationship requires four closure choices for the scaling behavior of glacier widths, slopes, side drag and mass balance. Reasonable closures predict a volume-area scaling exponent which is consistent with observations, giving a physical and practical basis for estimating ice volumes. Glacier volume is insensitive to perturbations in the mass balance scaling, but changes in average accumulation area ratios reflect significant changes in the scaling of both mass balance and ice volume. Copyright 1997 by the American Geophysical Union.

Cross-sectional and longitudinal evaluation of liver volume and total liver fat burden in adults with nonalcoholic steatohepatitis

PubMed Central

Tang, An; Chen, Joshua; Le, Thuy-Anh; Changchien, Christopher; Hamilton, Gavin; Middleton, Michael S.; Loomba, Rohit; Sirlin, Claude B.

2014-01-01

Purpose To explore the cross-sectional and longitudinal relationships between fractional liver fat content, liver volume, and total liver fat burden. Methods In 43 adults with non-alcoholic steatohepatitis participating in a clinical trial, liver volume was estimated by segmentation of magnitude-based low-flip-angle multiecho GRE images. The liver mean proton density fat fraction (PDFF) was calculated. The total liver fat index (TLFI) was estimated as the product of liver mean PDFF and liver volume. Linear regression analyses were performed. Results Cross-sectional analyses revealed statistically significant relationships between TLFI and liver mean PDFF (R2 = 0.740 baseline/0.791 follow-up, P < 0.001 baseline/P < 0.001 follow-up), and between TLFI and liver volume (R2 = 0.352/0.452, P < 0.001/< 0.001). Longitudinal analyses revealed statistically significant relationships between liver volume change and liver mean PDFF change (R2 = 0.556, P < 0.001), between TLFI change and liver mean PDFF change (R2 = 0.920, P < 0.001), and between TLFI change and liver volume change (R2 = 0.735, P < 0.001). Conclusion Liver segmentation in combination with MRI-based PDFF estimation may be used to monitor liver volume, liver mean PDFF, and TLFI in a clinical trial. PMID:25015398

Developing a stochastic traffic volume prediction model for public-private partnership projects

NASA Astrophysics Data System (ADS)

Phong, Nguyen Thanh; Likhitruangsilp, Veerasak; Onishi, Masamitsu

2017-11-01

Transportation projects require an enormous amount of capital investment resulting from their tremendous size, complexity, and risk. Due to the limitation of public finances, the private sector is invited to participate in transportation project development. The private sector can entirely or partially invest in transportation projects in the form of Public-Private Partnership (PPP) scheme, which has been an attractive option for several developing countries, including Vietnam. There are many factors affecting the success of PPP projects. The accurate prediction of traffic volume is considered one of the key success factors of PPP transportation projects. However, only few research works investigated how to predict traffic volume over a long period of time. Moreover, conventional traffic volume forecasting methods are usually based on deterministic models which predict a single value of traffic volume but do not consider risk and uncertainty. This knowledge gap makes it difficult for concessionaires to estimate PPP transportation project revenues accurately. The objective of this paper is to develop a probabilistic traffic volume prediction model. First, traffic volumes were estimated following the Geometric Brownian Motion (GBM) process. Monte Carlo technique is then applied to simulate different scenarios. The results show that this stochastic approach can systematically analyze variations in the traffic volume and yield more reliable estimates for PPP projects.

Comparison of three methods for the estimation of pineal gland volume using magnetic resonance imaging.

PubMed

Acer, Niyazi; Ilıca, Ahmet Turan; Turgut, Ahmet Tuncay; Ozçelik, Ozlem; Yıldırım, Birdal; Turgut, Mehmet

2012-01-01

Pineal gland is a very important neuroendocrine organ with many physiological functions such as regulating circadian rhythm. Radiologically, the pineal gland volume is clinically important because it is usually difficult to distinguish small pineal tumors via magnetic resonance imaging (MRI). Although many studies have estimated the pineal gland volume using different techniques, to the best of our knowledge, there has so far been no stereological work done on this subject. The objective of the current paper was to determine the pineal gland volume using stereological methods and by the region of interest (ROI) on MRI. In this paper, the pineal gland volumes were calculated in a total of 62 subjects (36 females, 26 males) who were free of any pineal lesions or tumors. The mean ± SD pineal gland volumes of the point-counting, planimetry, and ROI groups were 99.55 ± 51.34, 102.69 ± 40.39, and 104.33 ± 40.45 mm(3), respectively. No significant difference was found among the methods of calculating pineal gland volume (P > 0.05). From these results, it can be concluded that each technique is an unbiased, efficient, and reliable method, ideally suitable for in vivo examination of MRI data for pineal gland volume estimation.

Comparison of Three Methods for the Estimation of Pineal Gland Volume Using Magnetic Resonance Imaging

PubMed Central

Acer, Niyazi; Ilıca, Ahmet Turan; Turgut, Ahmet Tuncay; Özçelik, Özlem; Yıldırım, Birdal; Turgut, Mehmet

2012-01-01

Pineal gland is a very important neuroendocrine organ with many physiological functions such as regulating circadian rhythm. Radiologically, the pineal gland volume is clinically important because it is usually difficult to distinguish small pineal tumors via magnetic resonance imaging (MRI). Although many studies have estimated the pineal gland volume using different techniques, to the best of our knowledge, there has so far been no stereological work done on this subject. The objective of the current paper was to determine the pineal gland volume using stereological methods and by the region of interest (ROI) on MRI. In this paper, the pineal gland volumes were calculated in a total of 62 subjects (36 females, 26 males) who were free of any pineal lesions or tumors. The mean ± SD pineal gland volumes of the point-counting, planimetry, and ROI groups were 99.55 ± 51.34, 102.69 ± 40.39, and 104.33 ± 40.45 mm3, respectively. No significant difference was found among the methods of calculating pineal gland volume (P > 0.05). From these results, it can be concluded that each technique is an unbiased, efficient, and reliable method, ideally suitable for in vivo examination of MRI data for pineal gland volume estimation. PMID:22619577

Rain Volume Estimation over Areas Using Satellite and Radar Data

NASA Technical Reports Server (NTRS)

Doneaud, A. A.; Miller, J. R., Jr.; Johnson, L. R.; Vonderhaar, T. H.; Laybe, P.

1984-01-01

The application of satellite data to a recently developed radar technique used to estimate convective rain volumes over areas on a dry environment (the northern Great Plains) is discussed. The area time integral technique (ATI) provides a means of estimating total rain volumes over fixed and floating target areas of the order of 1,000 to 100,000 km(2) for clusters lasting 40 min. The basis of the method is the existence of a strong correlation between the area coverage integrated over the lifetime of the storm (ATI) and the rain volume. One key element in this technique is that it does not require the consideration of the structure of the radar intensities inside the area coverage to generate rain volumes, but only considers the rain event per se. This fact might reduce or eliminate some sources of error in applying the technique to satellite data. The second key element is that the ATI once determined can be converted to total rain volume by using a constant factor (average rain rate) for a given locale.

A Novel Application for the Cavalieri Principle: A Stereological and Methodological Study

PubMed Central

Altunkaynak, Berrin Zuhal; Altunkaynak, Eyup; Unal, Deniz; Unal, Bunyamin

2009-01-01

Objective The Cavalieri principle was applied to consecutive pathology sections that were photographed at the same magnification and used to estimate tissue volumes via superimposing a point counting grid on these images. The goal of this study was to perform the Cavalieri method quickly and practically. Materials and Methods In this study, 10 adult female Sprague Dawley rats were used. Brain tissue was removed and sampled both systematically and randomly. Brain volumes were estimated using two different methods. First, all brain slices were scanned with an HP ScanJet 3400C scanner, and their images were shown on a PC monitor. Brain volume was then calculated based on these images. Second, all brain slices were photographed in 10× magnification with a microscope camera, and brain volumes were estimated based on these micrographs. Results There was no statistically significant difference between the volume measurements of the two techniques (P>0.05; Paired Samples t Test). Conclusion This study demonstrates that personal computer scanning of serial tissue sections allows for easy and reliable volume determination based on the Cavalieri method. PMID:25610077

A novel application for the cavalieri principle: a stereological and methodological study.

PubMed

Altunkaynak, Berrin Zuhal; Altunkaynak, Eyup; Unal, Deniz; Unal, Bunyamin

2009-08-01

The Cavalieri principle was applied to consecutive pathology sections that were photographed at the same magnification and used to estimate tissue volumes via superimposing a point counting grid on these images. The goal of this study was to perform the Cavalieri method quickly and practically. In this study, 10 adult female Sprague Dawley rats were used. Brain tissue was removed and sampled both systematically and randomly. Brain volumes were estimated using two different methods. First, all brain slices were scanned with an HP ScanJet 3400C scanner, and their images were shown on a PC monitor. Brain volume was then calculated based on these images. Second, all brain slices were photographed in 10× magnification with a microscope camera, and brain volumes were estimated based on these micrographs. There was no statistically significant difference between the volume measurements of the two techniques (P>0.05; Paired Samples t Test). This study demonstrates that personal computer scanning of serial tissue sections allows for easy and reliable volume determination based on the Cavalieri method.

A Spanish model for quantification and management of construction waste.

PubMed

Solís-Guzmán, Jaime; Marrero, Madelyn; Montes-Delgado, Maria Victoria; Ramírez-de-Arellano, Antonio

2009-09-01

Currently, construction and demolition waste (C&D waste) is a worldwide issue that concerns not only governments but also the building actors involved in construction activity. In Spain, a new national decree has been regulating the production and management of C&D waste since February 2008. The present work describes the waste management model that has inspired this decree: the Alcores model implemented with good results in Los Alcores Community (Seville, Spain). A detailed model is also provided to estimate the volume of waste that is expected to be generated on the building site. The quantification of C&D waste volume, from the project stage, is essential for the building actors to properly plan and control its disposal. This quantification model has been developed by studying 100 dwelling projects, especially their bill of quantities, and defining three coefficients to estimate the demolished volume (CT), the wreckage volume (CR) and the packaging volume (CE). Finally, two case studies are included to illustrate the usefulness of the model to estimate C&D waste volume in both new construction and demolition projects.

Neighborhood Poverty. Policy Implications in Studying Neighborhoods. Volume II.

ERIC Educational Resources Information Center

Brooks-Gunn, Jeanne, Ed.; Duncan, Greg J., Ed.; Aber, J. Lawrence, Ed.

Volume 2 of the "Neighborhood Poverty" series incorporates empirical data on neighborhood poverty into discussions of policy and program development. The chapters are: (1) "Ecological Perspectives on the Neighborhood Context of Urban Poverty: Past and Present" (Robert J. Sampson and Jeffrey D. Morenoff); (2) "The Influence of Neighborhoods on…

MRI Amygdala Volume in Williams Syndrome

ERIC Educational Resources Information Center

Capitao, Liliana; Sampaio, Adriana; Sampaio, Cassandra; Vasconcelos, Cristiana; Fernandez, Montse; Garayzabal, Elena; Shenton, Martha E.; Goncalves, Oscar F.

2011-01-01

One of the most intriguing characteristics of Williams Syndrome individuals is their hypersociability. The amygdala has been consistently implicated in the etiology of this social profile, particularly given its role in emotional and social behavior. This study examined amygdala volume and symmetry in WS individuals and in age and sex matched…

Strategies for Retaining Minority Students in Higher Education.

ERIC Educational Resources Information Center

Lang, Marvel, Ed.; Ford, Clinita A., Ed.

This volume contains selected papers presented at National Black Student Retention Conferences between 1988 and 1991, that examine ideas concerning educational access and retention. The volume and papers are divided into three groupings which address: (1) The Psycho-Social Implications; (2) Model Strategies and Programs; and (3) Impacts of Faculty…

Improved biovolume estimation of Microcystis aeruginosa colonies: A statistical approach.

PubMed

Alcántara, I; Piccini, C; Segura, A M; Deus, S; González, C; Martínez de la Escalera, G; Kruk, C

2018-05-27

The Microcystis aeruginosa complex (MAC) clusters many of the most common freshwater and brackish bloom-forming cyanobacteria. In monitoring protocols, biovolume estimation is a common approach to determine MAC colonies biomass and useful for prediction purposes. Biovolume (μm 3 mL -1 ) is calculated multiplying organism abundance (orgL -1 ) by colonial volume (μm 3 org -1 ). Colonial volume is estimated based on geometric shapes and requires accurate measurements of dimensions using optical microscopy. A trade-off between easy-to-measure but low-accuracy simple shapes (e.g. sphere) and time costly but high-accuracy complex shapes (e.g. ellipsoid) volume estimation is posed. Overestimations effects in ecological studies and management decisions associated to harmful blooms are significant due to the large sizes of MAC colonies. In this work, we aimed to increase the precision of MAC biovolume estimations by developing a statistical model based on two easy-to-measure dimensions. We analyzed field data from a wide environmental gradient (800 km) spanning freshwater to estuarine and seawater. We measured length, width and depth from ca. 5700 colonies under an inverted microscope and estimated colonial volume using three different recommended geometrical shapes (sphere, prolate spheroid and ellipsoid). Because of the non-spherical shape of MAC the ellipsoid resulted in the most accurate approximation, whereas the sphere overestimated colonial volume (3-80) especially for large colonies (MLD higher than 300 μm). Ellipsoid requires measuring three dimensions and is time-consuming. Therefore, we constructed different statistical models to predict organisms depth based on length and width. Splitting the data into training (2/3) and test (1/3) sets, all models resulted in low training (1.41-1.44%) and testing average error (1.3-2.0%). The models were also evaluated using three other independent datasets. The multiple linear model was finally selected to calculate MAC volume as an ellipsoid based on length and width. This work contributes to achieve a better estimation of MAC volume applicable to monitoring programs as well as to ecological research. Copyright © 2017. Published by Elsevier B.V.

Novel Approach to Estimate Kidney and Cyst Volumes using Mid-Slice Magnetic Resonance Images in Polycystic Kidney Disease

PubMed Central

Bae, Kyongtae T; Tao, Cheng; Wang, Jinhong; Kaya, Diana; Wu, Zhiyuan; Bae, Junu T; Chapman, Arlene B; Torres, Vicente E; Grantham, Jared J; Mrug, Michal; Bennett, William M; Flessner, Michael F; Landsittel, Doug P

2013-01-01

Objective To evaluate whether kidney and cyst volumes can be accurately estimated based on limited area measurements from MR images of patients with autosomal dominant polycystic kidney disease (ADPKD). Materials and Methods MR coronal images of 178 ADPKD participants from the Consortium for Radiologic Imaging Studies of ADPKD (CRISP) were analyzed. For each MR image slice, we measured kidney and renal cyst areas using stereology and region-based thresholding methods, respectively. The kidney and cyst ‘observed’ volumes were calculated by summing up the area measurements of all the slices covering the kidney. To estimate the volume, we selected a coronal mid-slice in each kidney and multiplied its area by the total number of slices (‘PANK2’ for kidney and ‘PANC2’ for cyst). We then compared the kidney and cyst volumes predicted from PANK2 and PANC2, respectively, to the corresponding observed volumes, using a linear regression analysis. Results The kidney volume predicted from PANK2 correlated extremely well with the observed kidney volume: R2=0.994 for right and 0.991 for left kidney. The linear regression coefficient multiplier to PANK2 that best fit the kidney volume was 0.637 (95%CI: 0.629–0.644) for right and 0.624 (95%CI: 0.616–0.633) for left kidney. The correlation between the cyst volume predicted from PANC2 and the observed cyst volume was also very high: R2=0.984 for right and 0.967 for left kidney. The least squares linear regression coefficient for PANC2 was 0.637 (95%CI: 0.624–0.649) for right and 0.608 (95%CI: 0.591–0.625) for left kidney. Conclusion Kidney and cyst volumes can be closely approximated by multiplying the product of the mid-slice area measurement and the total number of slices in the coronal MR images of ADPKD kidneys by 0.61–0.64. This information will help save processing time needed to estimate total kidney and cyst volumes of ADPKD kidneys. PMID:24107679

Stereological estimation of ovarian oocyte volume, surface area and number: application on mice treated with nandrolone decanoate.

PubMed

Karbalay-Doust, Saied; Noorafshan, Ali

2012-07-05

Changes in the number and size of oocytes can lead to fertilization problems. The present study aimed to evaluate the number, volume, and surface area of oocytes in healthy as well as nandrolone decanoate-treated (ND) mice using stereological methods. Five control mice received vehicle, and five ND-treated mice received ND. Using the 'isotropic Cavalieri' design', the ovary was sectioned. The volume of the ovary (cortex and medulla) was estimated. The oocytes' volume and surface area were estimated using the invariator. The number of the oocytes was estimated using an optical disector. The volumes of the ovary, cortex, and medulla decreased ~50% in the ND-treated mice. The mean number (coefficient of variation) of preantral, antral, and atretic oocytes in the control ovary were 1,690 (0.29), 2,100 (0.52), and 3,900 (0.2), respectively, which decreased ~54%, ~87%, and ~91%, respectively in the ND-treated animals. The mean volume (coefficient of variation) of the preantral, antral, and atretic oocytes were 86,000 (0.27), 110,000 (0.48), and 27,000 (0.33) μm³, respectively. The mean surface area (coefficient of variation) of the three types of oocytes were 9,000 (0.24), 9,900 (0.28), and 4,700 (0.21) μm², respectively. These parameters remained unchanged in the ND-treated mice. ND induces reduction in the number of oocytes, but not in the volume or the surface area.

Trends in Arctic Sea Ice Volume 2010-2013 from CryoSat-2

NASA Astrophysics Data System (ADS)

Tilling, R.; Ridout, A.; Wingham, D.; Shepherd, A.; Haas, C.; Farrell, S. L.; Schweiger, A. J.; Zhang, J.; Giles, K.; Laxon, S.

2013-12-01

Satellite records show a decline in Arctic sea ice extent over the past three decades with a record minimum in September 2012, and results from the Pan-Arctic Ice-Ocean Modelling and Assimilation System (PIOMAS) suggest that this has been accompanied by a reduction in volume. We use three years of measurements recorded by the European Space Agency CryoSat-2 (CS-2) mission, validated with in situ data, to generate estimates of seasonal variations and inter-annual trends in Arctic sea ice volume between 2010 and 2013. The CS-2 estimates of sea ice thickness agree with in situ estimates derived from upward looking sonar measurements of ice draught and airborne measurements of ice thickness and freeboard to within 0.1 metres. Prior to the record minimum in summer 2012, autumn and winter Arctic sea ice volume had fallen by ~1300 km3 relative to the previous year. Using the full 3-year period of CS-2 observations, we estimate that winter Arctic sea ice volume has decreased by ~700 km3/yr since 2010, approximately twice the average rate since 1980 as predicted by the PIOMAS.

Microionization chamber for reference dosimetry in IMRT verification: clinical implications on OAR dosimetric errors

NASA Astrophysics Data System (ADS)

Sánchez-Doblado, Francisco; Capote, Roberto; Leal, Antonio; Roselló, Joan V.; Lagares, Juan I.; Arráns, Rafael; Hartmann, Günther H.

2005-03-01

Intensity modulated radiotherapy (IMRT) has become a treatment of choice in many oncological institutions. Small fields or beamlets with sizes of 1 to 5 cm2 are now routinely used in IMRT delivery. Therefore small ionization chambers (IC) with sensitive volumes <=0.1 cm3are generally used for dose verification of an IMRT treatment. The measurement conditions during verification may be quite different from reference conditions normally encountered in clinical beam calibration, so dosimetry of these narrow photon beams pertains to the so-called non-reference conditions for beam calibration. This work aims at estimating the error made when measuring the organ at risk's (OAR) absolute dose by a micro ion chamber (μIC) in a typical IMRT treatment. The dose error comes from the assumption that the dosimetric parameters determining the absolute dose are the same as for the reference conditions. We have selected two clinical cases, treated by IMRT, for our dose error evaluations. Detailed geometrical simulation of the μIC and the dose verification set-up was performed. The Monte Carlo (MC) simulation allows us to calculate the dose measured by the chamber as a dose averaged over the air cavity within the ion-chamber active volume (Dair). The absorbed dose to water (Dwater) is derived as the dose deposited inside the same volume, in the same geometrical position, filled and surrounded by water in the absence of the ion chamber. Therefore, the Dwater/Dair dose ratio is the MC estimator of the total correction factor needed to convert the absorbed dose in air into the absorbed dose in water. The dose ratio was calculated for the μIC located at the isocentre within the OARs for both clinical cases. The clinical impact of the calculated dose error was found to be negligible for the studied IMRT treatments.

Flow-gradient patterns in severe aortic stenosis with preserved ejection fraction: clinical characteristics and predictors of survival.

PubMed

Eleid, Mackram F; Sorajja, Paul; Michelena, Hector I; Malouf, Joseph F; Scott, Christopher G; Pellikka, Patricia A

2013-10-15

Among patients with severe aortic stenosis (AS) and preserved ejection fraction, those with low gradient (LG) and reduced stroke volume may have an adverse prognosis. We investigated the prognostic impact of stroke volume using the recently proposed flow-gradient classification. We examined 1704 consecutive patients with severe AS (aortic valve area <1.0 cm(2)) and preserved ejection fraction (≥50%) using 2-dimensional and Doppler echocardiography. Patients were stratified by stroke volume index (<35 mL/m(2) [low flow, LF] versus ≥35 mL/m(2) [normal flow, NF]) and aortic gradient (<40 mm Hg [LG] versus ≥40 mm Hg [high gradient, HG]) into 4 groups: NF/HG, NF/LG, LF/HG, and LF/LG. NF/LG (n=352, 21%), was associated with favorable survival with medical management (2-year estimate, 82% versus 67% in NF/HG; P<0.0001). LF/LG severe AS (n=53, 3%) was characterized by lower ejection fraction, more prevalent atrial fibrillation and heart failure, reduced arterial compliance, and reduced survival (2-year estimate, 60% versus 82% in NF/HG; P<0.001). In multivariable analysis, the LF/LG pattern was the strongest predictor of mortality (hazard ratio, 3.26; 95% confidence interval, 1.71-6.22; P<0.001 versus NF/LG). Aortic valve replacement was associated with a 69% mortality reduction (hazard ratio, 0.31; 95% confidence interval, 0.25-0.39; P<0.0001) in LF/LG and NF/HG, with no survival benefit associated with aortic valve replacement in NF/LG and LF/HG. NF/LG severe AS with preserved ejection fraction exhibits favorable survival with medical management, and the impact of aortic valve replacement on survival was neutral. LF/LG severe AS is characterized by a high prevalence of atrial fibrillation, heart failure, and reduced survival, and aortic valve replacement was associated with improved survival. These findings have implications for the evaluation and subsequent management of AS severity.

Case Studies in Educational Performance Contracting. Part 1. Conclusions and Implications.

ERIC Educational Resources Information Center

Carpenter, Polly; Hall, George R.

This volume presents conclusions and implications derived from five cities' experience with performance contracting in education: Norfolk, Virginia; Texarkana, Arkansas (with Liberty-Eylau, Texas); Gary, Indiana, Gilroy, California; and Grand Rapids, Michigan. The five case studies cover eight programs in 15 schools. While each study is treated in…

Collaborative Learning: Higher Education, Interdependence, and the Authority of Knowledge.

ERIC Educational Resources Information Center

Bruffee, Kenneth A.

This volume explores the role and implications of collaborative learning for the mission and future of higher education and college teaching. Part I discusses the implications of nonfoundational social constructionist thought for colleges and universities. Nonfoundational notions of knowledge and social relations argue that knowledge has no…

Estimation of the outer-sphere contribution to the activation volume for electron exchange reactions using the mean spherical approximation

NASA Astrophysics Data System (ADS)

Takagi, Hideo D.; Swaddle, Thomas W.

1996-01-01

The outer-sphere contribution to the volume of activation of homogeneous electron exchange reactions is estimated for selected solvents on the basis of the mean spherical approximation (MSA), and the calculated values are compared with those estimated by the Strank-Hush-Marcus (SHM) theory and with activation volumes obtained experimentally for the electron exchange reaction between tris(hexafluoroacetylacetonato)ruthenium(III) and -(II) in acetone, acetonitrile, methanol and chloroform. The MSA treatment, which recognizes the molecular nature of the solvent, does not improve significantly upon the continuous-dielectric SHM theory, which represents the experimental data adequately for the more polar solvents.

Neighborhood Variation of Sustainable Urban Morphological Characteristics.

PubMed

Lai, Poh-Chin; Chen, Si; Low, Chien-Tat; Cerin, Ester; Stimson, Robert; Wong, Pui Yun Paulina

2018-03-07

Compact cities and their urban forms have implications on sustainable city development because of high density urban settlement, increased accessibility, and a balanced land use mix. This paper uses quantitative means of understanding urban morphological characteristics with reference to the differing qualities of the urban form (i.e., street patterns, building volumes, land uses and greenery). The results, based on 89 neighborhood communities of Hong Kong, show varying degrees of regional differences in the urban built form supported by numerical statistics and graphical illustrations. This paper offers empirical evidence on some morphological characteristics that can be estimated objectively using modern geospatial technologies and applied universally to inform urban planning. However, more studies linking these quantifiable measures of the physical form with sustainable urban living are needed to account for human comfort in the totality of environmental, social, and economic responsibilities.

Neighborhood Variation of Sustainable Urban Morphological Characteristics

PubMed Central

Chen, Si; Stimson, Robert

2018-01-01

Compact cities and their urban forms have implications on sustainable city development because of high density urban settlement, increased accessibility, and a balanced land use mix. This paper uses quantitative means of understanding urban morphological characteristics with reference to the differing qualities of the urban form (i.e., street patterns, building volumes, land uses and greenery). The results, based on 89 neighborhood communities of Hong Kong, show varying degrees of regional differences in the urban built form supported by numerical statistics and graphical illustrations. This paper offers empirical evidence on some morphological characteristics that can be estimated objectively using modern geospatial technologies and applied universally to inform urban planning. However, more studies linking these quantifiable measures of the physical form with sustainable urban living are needed to account for human comfort in the totality of environmental, social, and economic responsibilities. PMID:29518956

Left atrium by echocardiography in clinical practice: from conventional methods to new echocardiographic techniques.

PubMed

Ancona, Roberta; Comenale Pinto, Salvatore; Caso, Pio; D'Andrea, Antonello; Di Salvo, Giovanni; Arenga, Fortunato; Coppola, Maria Gabriella; Sellitto, Vincenzo; Macrino, Maria; Calabrò, Raffaele

2014-01-01

Although often referred to as "the forgotten chamber", compared with left ventricle (LV), especially in the past years, the left atrium (LA) plays a critical role in the clinical expression and prognosis of patients with heart and cerebrovascular disease, as demonstrated by several studies. Echocardiographers initially focused on early detection of atrial geometrical abnormalities through monodimensional atrial diameter quantification and then bidimensional (2D) areas and volume estimation. Now, together with conventional echocardiographic parameters, new echocardiographic techniques, such as strain Doppler, 2D speckle tracking and three-dimensional (3D) echocardiography, allow assessing early LA dysfunction and they all play a fundamental role to detect early functional remodelling before anatomical alterations occur. LA dysfunction and its important prognostic implications may be detected sooner by LA strain than by volumetric measurements.

Concentrations of Prioritized Pharmaceuticals in Effluents from 50 Large Wastewater Treatment Plants in the US and Implications for Risk Estimation

EPA Pesticide Factsheets

PDF file of Concentrations of Prioritized Pharmaceuticals in Effluents from 50 Large Wastewater Treatment Plants in the US and Implications for Risk Estimation by Mitchell Kostich, Angella Batt, and James Lazorchak

Simple estimate of critical volume

NASA Technical Reports Server (NTRS)

Fedors, R. F.

1980-01-01

Method for estimating critical molar volume of materials is faster and simpler than previous procedures. Formula sums no more than 18 different contributions from components of chemical structure of material, and is as accurate (within 3 percent) as older more complicated models. Method should expedite many thermodynamic design calculations.

Volume quantification by contrast-enhanced ultrasound: an in-vitro comparison with true volumes and thermodilution.

PubMed

Herold, Ingeborg H F; Russo, Gianna; Mischi, Massimo; Houthuizen, Patrick; Saidov, Tamerlan; van het Veer, Marcel; van Assen, Hans C; Korsten, Hendrikus H M

2013-10-17

Contrast-enhanced ultrasound (CEUS) has recently been proposed as a minimally- invasive, alternative method for blood volume measurement. This study aims at comparing the accuracy of CEUS and the classical thermodilution techniques for volume assessment in an in-vitro set-up. The in-vitro set-up consisted of a variable network between an inflow and outflow tube and a roller pump. The inflow and outflow tubes were insonified with an ultrasound array transducer and a thermistor was placed in each tube. Indicator dilution curves were made by injecting indicator which consisted of an ultrasound-contrast-agent diluted in ice-cold saline. Both acoustic intensity- and thermo-dilution curves were used to calculate the indicator mean transit time between the inflow and outflow tube. The volumes were derived by multiplying the estimated mean transit time by the flow rate. We compared the volumes measured by CEUS with the true volumes of the variable network and those measured by thermodilution by Bland-Altman and intraclass-correlation analysis. The measurements by CEUS and thermodilution showed a very strong correlation (rs = 0.94) with a modest volume underestimation by CEUS of -40 ± 28 mL and an overestimation of 84 ± 62 mL by thermodilution compared with the true volumes. Both CEUS and thermodilution showed a high statistically significant correlation with the true volume (rs = 0.97 (95% CI, 0.95 - 0.98; P<0.0001) and rs = 0.96 (95% CI, 0.94 - 0.98; P<0.0001, respectively). CEUS volume estimation provides a strong correlation with both the true volumes in-vitro and volume estimation by thermodilution. It may therefore represent an interesting alternative to the standard, invasive thermodilution technique.

Estimating forest biomass and volume using airborne laser data

NASA Technical Reports Server (NTRS)

Nelson, Ross; Krabill, William; Tonelli, John

1988-01-01

An airborne pulsed laser system was used to obtain canopy height data over a southern pine forest in Georgia in order to predict ground-measured forest biomass and timber volume. Although biomass and volume estimates obtained from the laser data were variable when compared with the corresponding ground measurements site by site, the present models are found to predict mean total tree volume within 2.6 percent of the ground value, and mean biomass within 2.0 percent. The results indicate that species stratification did not consistently improve regression relationships for four southern pine species.

Assessment of potential additions to conventional oil and gas resources of the world (outside the United States) from reserve growth, 2012

USGS Publications Warehouse

Klett, Timothy R.; Cook, Troy A.; Charpentier, Ronald R.; Tennyson, Marilyn E.; Attanasi, E.D.; Freeman, Phil A.; Ryder, Robert T.; Gautier, Donald L.; Verma, Mahendra K.; Le, Phuong A.; Schenk, Christopher J.

2012-01-01

The U.S. Geological Survey estimated volumes of technically recoverable, conventional petroleum resources resulting from reserve growth for discovered fields outside the United States that have reported in-place oil and gas volumes of 500 million barrels of oil equivalent or greater. The mean volumes were estimated at 665 billion barrels of crude oil, 1,429 trillion cubic feet of natural gas, and 16 billion barrels of natural gas liquids. These volumes constitute a significant portion of the world's oil and gas resources.

District wide water resources investigation and management using LANDSAT data. Phase 1: Lake volume

NASA Technical Reports Server (NTRS)

Shih, S. F. (Principal Investigator)

1982-01-01

A technique for estimating available water storage volume using LANDSAT data was developed and applied to Lake Washington and Lake Harris in central Florida. The technique can be applied two ways. First, where the historical stage records are available, the historical LANDSAT data can be used to establish the relationship between lake volume and lake stage. In the second case, where the historical stage records are not available, the historical LANDSAT data can be used to estimate the historical lake stage after the lake volume and stage information become available in the future.

Carbon Emissions from Residue Burn Piles Estimated Using LiDAR or Ground Based Measurements of Pile Volumes in a Coastal Douglas-Fir Forest

NASA Astrophysics Data System (ADS)

Trofymow, J. A.; Coops, N.; Hayhurst, D.

2012-12-01

Following forest harvest, residues left on site and roadsides are often disposed of to reduce fire risk and free planting space. In coastal British Columbia burn piles are the main method of disposal, particularly for accumulations from log processing. Quantification of residue wood in piles is required for: smoke emission estimates, C budget calculations, billable waste assessment, harvest efficiency monitoring, and determination of bioenergy potentials. A second-growth Douglas-fir dominated (DF1949) site on eastern Vancouver Island and subject of C flux and budget studies since 1998, was clearcut in winter 2011, residues piled in spring and burned in fall. Prior to harvest, the site was divided into 4 blocks to account for harvest plans and ecosite conditions. Total harvested wood volume was scaled for each block. Residue pile wood volume was determined by a standard Waste and Residue Survey (WRS) using field estimates of pile base area and plot density (wood volume / 0.005 ha plot) on 2 piles per block, by a smoke emissions geometric method with pile volumes estimated as ellipsoidal paraboloids and packing ratios (wood volume / pile volume) for 2 piles per block, as well as by five other GIS methods using pile volumes and areas from LiDAR and orthophotography flown August 2011, a LiDAR derived digital elevation model (DEM) from 2008, and total scaled wood volumes of 8 sample piles disassembled November 2011. A weak but significant negative relationship was found between pile packing ratio and pile volume. Block level avoidable+unavoidable residue pile wood volumes from the WRS method (20.0 m3 ha-1 SE 2.8) were 30%-50% of the geometric (69.0 m3 ha-1 SE 18.0) or five GIS/LiDAR (48.0 to 65.7 m3 ha-1 ) methods. Block volumes using the 2008 LiDAR DEM (unshifted 48.0 m3 ha-1 SE 3.9, shifted 53.6 m3 ha-1 SE 4.2) to account for pre-existing humps or hollows beneath piles were not different from those using the 2011 LiDAR DEM (50.3 m3 ha-1 SE 4.0). The block volume ratio (total residue pile / harvest scale, wood volumes x 100) for the WRS method (3.3% SE 0.45) was lower than for LiDAR 2011 method (8.1% SE 0.31). Using wood densities from in situ samples and LiDAR 2011 method wood volumes, total residue pile wood biomass in the blocks was 21.5 t dry mass ha-1 (SE 1.9). Post-burn charred residues were ~1.5 t dry mass ha-1 resulting in C emission estimates of 10 t C ha-1 (SE 0.91), assuming 50% C, and equivalent to 2 - 3 years of pre-harvest stand C uptake (NEP 4.8 t C ha-1 y-1 SE 0.58). Results suggest the WRS method may underestimate residue pile wood volumes, while the geometric method may overestimate depending on packing ratio used. While remote sensing methods reduce uncertainty in estimating volumes or areas of all piles in a block, quantification of packing ratios remains a significant source of uncertainty in determining block level residue pile wood volumes. Additional studies are needed for other forest and harvest types to determine the wider applicability of these findings.

Accuracy and reproducibility of the measurement of actively circulating blood volume with an integrated fiberoptic monitoring system.

PubMed

Kisch, H; Leucht, S; Lichtwarck-Aschoff, M; Pfeiffer, U J

1995-05-01

Bedside monitoring of circulating blood volume has become possible with the introduction of an integrated fiberoptic monitoring system that calculates blood volume from the changes in blood concentration of indocyanine green dye 4 mins after injection. The aim of this investigation was to compare the blood volume estimate of the integrated fiberoptic monitoring system (group 1) with the standard methods of blood volume measurement using Evans blue (group 2), and indocyanine green measured photometrically (group 3). Prospective laboratory study. Animal laboratory of a University's institute for experimental surgery. Eleven anesthetized, paralyzed, and mechanically ventilated piglets. A central venous catheter was used for the injection of the indicator dyes (Evans blue and indocyanine green). A fiberoptic thermistor catheter was advanced into the thoracic aorta. The fiberoptic catheter detects indocyanine green by reflection densitometry for the estimation of blood volume of the integrated fiberoptic monitoring system. Samples for the determination of Evans blue and indocyanine green concentrations were drawn from an arterial catheter in the femoral artery over a period of 17 mins after injection. Measurements were performed during normovolemia, hypovolemia (blood withdrawal of < or = 30 mL/kg), and hypervolemia (retransfusion of the withdrawn blood plus an infusion of 10% hydroxyethyl starch [45 mL/kg]). Linear regression, correlation, and bias were calculated for the comparison of the blood volume estimates by the fiberoptic monitoring system (group 1) vs. the total blood volume estimates using Evans blue (group 2) and indocyanine green (group 3): group 1 = 0.82.group 2-26 mL; r2 = 82.71%; r = .91; n = 40; group 1-group 2 +/- 1 SD = -435 +/- 368 mL; group 1 = 0.79.group 3 + 50 mL; r2 = 74.81%; r = .87; n = 28; group 1-group 3 +/- 1 SD = -506 +/- 374 mL. The results demonstrate that the blood volume estimate of the fiberoptic monitoring system (group 1) correlates closely with the total blood volume measurement using Evans blue (group 2) and indocyanine green (group 3). Trapped indicator in the packed red cell column after centrifugation of the blood samples may account for an overestimation of group 2 and group 3 of approximately 10% to 14%, but there still remains a proportional difference of 10% between group 1 vs. group 2 and vs. group 3. This difference is due to the longer mixing times of group 3 (16 mins) and group 2 (17 mins), during which they are distributed in slowly exchanging blood pools. It seems that the blood volume estimate of the fiberoptic monitoring system (group 1) represents the actively circulating blood volume and may be useful for bedside monitoring.

Methods and equations for estimating aboveground volume, biomass, and carbon for trees in the U.S. forest inventory, 2010

Treesearch

Christopher W. Woodall; Linda S. Heath; Grant M. Domke; Michael C. Nichols

2011-01-01

The U.S. Forest Service, Forest Inventory and Analysis (FIA) program uses numerous models and associated coefficients to estimate aboveground volume, biomass, and carbon for live and standing dead trees for most tree species in forests of the United States. The tree attribute models are coupled with FIA's national inventory of sampled trees to produce estimates of...

Constraining explosive volcanism: subjective choices during estimates of eruption magnitude

USGS Publications Warehouse

Klawonn, Malin; Houghton, Bruce F.; Swanson, Don; Fagents, Sarah A.; Wessel, Paul; Wolfe, Cecily J.

2014-01-01

When estimating the magnitude of explosive eruptions from their deposits, individuals make three sets of critical choices with respect to input data: the spacing of sampling sites, the selection of contour intervals to constrain the field measurements, and the hand contouring of thickness/isomass data, respectively. Volcanologists make subjective calls, as there are no accepted published protocols and few accounts of how these choices will impact estimates of eruption magnitude. Here, for the first time, we took a set of unpublished thickness measurements from the 1959 Kīlauea Iki pyroclastic fall deposit and asked 101 volcanologists worldwide to hand contour the data. First, there were surprisingly consistent volume estimates across maps with three different sampling densities. Second, the variability in volume calculations imparted by individuals’ choices of contours is also surprisingly low and lies between s = 5 and 8 %. Third, volume estimation is insensitive to the extent to which different individuals “smooth” the raw data in constructing contour lines. Finally, large uncertainty is associated with the construction of the thinnest isopachs, which is likely to underestimate the actual trend of deposit thinning. The net result is that researchers can have considerable confidence in using volume or dispersal data from multiple authors and different deposits for comparative studies. These insights should help volcanologists around the world to optimize design and execution of field-based studies to characterize accurately the volume of pyroclastic deposits.

Constraining explosive volcanism: subjective choices during estimates of eruption magnitude

NASA Astrophysics Data System (ADS)

Klawonn, Malin; Houghton, Bruce F.; Swanson, Donald A.; Fagents, Sarah A.; Wessel, Paul; Wolfe, Cecily J.

2014-02-01

When estimating the magnitude of explosive eruptions from their deposits, individuals make three sets of critical choices with respect to input data: the spacing of sampling sites, the selection of contour intervals to constrain the field measurements, and the hand contouring of thickness/isomass data, respectively. Volcanologists make subjective calls, as there are no accepted published protocols and few accounts of how these choices will impact estimates of eruption magnitude. Here, for the first time, we took a set of unpublished thickness measurements from the 1959 Kīlauea Iki pyroclastic fall deposit and asked 101 volcanologists worldwide to hand contour the data. First, there were surprisingly consistent volume estimates across maps with three different sampling densities. Second, the variability in volume calculations imparted by individuals' choices of contours is also surprisingly low and lies between s = 5 and 8 %. Third, volume estimation is insensitive to the extent to which different individuals "smooth" the raw data in constructing contour lines. Finally, large uncertainty is associated with the construction of the thinnest isopachs, which is likely to underestimate the actual trend of deposit thinning. The net result is that researchers can have considerable confidence in using volume or dispersal data from multiple authors and different deposits for comparative studies. These insights should help volcanologists around the world to optimize design and execution of field-based studies to characterize accurately the volume of pyroclastic deposits.

Geometric k-nearest neighbor estimation of entropy and mutual information

NASA Astrophysics Data System (ADS)

Lord, Warren M.; Sun, Jie; Bollt, Erik M.

2018-03-01

Nonparametric estimation of mutual information is used in a wide range of scientific problems to quantify dependence between variables. The k-nearest neighbor (knn) methods are consistent, and therefore expected to work well for a large sample size. These methods use geometrically regular local volume elements. This practice allows maximum localization of the volume elements, but can also induce a bias due to a poor description of the local geometry of the underlying probability measure. We introduce a new class of knn estimators that we call geometric knn estimators (g-knn), which use more complex local volume elements to better model the local geometry of the probability measures. As an example of this class of estimators, we develop a g-knn estimator of entropy and mutual information based on elliptical volume elements, capturing the local stretching and compression common to a wide range of dynamical system attractors. A series of numerical examples in which the thickness of the underlying distribution and the sample sizes are varied suggest that local geometry is a source of problems for knn methods such as the Kraskov-Stögbauer-Grassberger estimator when local geometric effects cannot be removed by global preprocessing of the data. The g-knn method performs well despite the manipulation of the local geometry. In addition, the examples suggest that the g-knn estimators can be of particular relevance to applications in which the system is large, but the data size is limited.

It's what's inside that counts: egg contaminant concentrations are influenced by estimates of egg density, egg volume, and fresh egg mass.

PubMed

Herzog, Mark P; Ackerman, Joshua T; Eagles-Smith, Collin A; Hartman, C Alex

2016-05-01

In egg contaminant studies, it is necessary to calculate egg contaminant concentrations on a fresh wet weight basis and this requires accurate estimates of egg density and egg volume. We show that the inclusion or exclusion of the eggshell can influence egg contaminant concentrations, and we provide estimates of egg density (both with and without the eggshell) and egg-shape coefficients (used to estimate egg volume from egg morphometrics) for American avocet (Recurvirostra americana), black-necked stilt (Himantopus mexicanus), and Forster's tern (Sterna forsteri). Egg densities (g/cm(3)) estimated for whole eggs (1.056 ± 0.003) were higher than egg densities estimated for egg contents (1.024 ± 0.001), and were 1.059 ± 0.001 and 1.025 ± 0.001 for avocets, 1.056 ± 0.001 and 1.023 ± 0.001 for stilts, and 1.053 ± 0.002 and 1.025 ± 0.002 for terns. The egg-shape coefficients for egg volume (K v ) and egg mass (K w ) also differed depending on whether the eggshell was included (K v  = 0.491 ± 0.001; K w  = 0.518 ± 0.001) or excluded (K v  = 0.493 ± 0.001; K w  = 0.505 ± 0.001), and varied among species. Although egg contaminant concentrations are rarely meant to include the eggshell, we show that the typical inclusion of the eggshell in egg density and egg volume estimates results in egg contaminant concentrations being underestimated by 6-13 %. Our results demonstrate that the inclusion of the eggshell significantly influences estimates of egg density, egg volume, and fresh egg mass, which leads to egg contaminant concentrations that are biased low. We suggest that egg contaminant concentrations be calculated on a fresh wet weight basis using only internal egg-content densities, volumes, and masses appropriate for the species. For the three waterbirds in our study, these corrected coefficients are 1.024 ± 0.001 for egg density, 0.493 ± 0.001 for K v , and 0.505 ± 0.001 for K w .

Magmatic-Tectonic Interactions: Implications for Seismic Hazard Assessment in the Central Walker Lane and Long Valley Caldera Regions

NASA Astrophysics Data System (ADS)

Chacko, R.; Hammond, W. C.; Blewitt, G.; Bormann, J. M.

2014-12-01

Accurate estimates of fault slip rates based on geodetic data rely on measurements that represent the long-term deformation of the crust. In the Central Walker Lane/Sierra Nevada transition, the Long Valley Caldera region has experienced multiple episodes of uplift and subsidence during the last four decades. The latest episode began in late 2011 and is detectable as a transient signal in the time series of GPS stations around the caldera. These transient signals become more apparent and reveal the extent of the impact on the ambient crustal deformation field of the Walker Lane when the velocity vectors are transformed to a Sierra-Nevada reference frame. Estimating contemporary slip-rates on faults for the purpose of seismic hazard assessment in the region around Long Valley requires detecting and subtracting the transient signals caused by the uplift and subsidence in the caldera. We estimate the geographic extent to which the ambient crustal deformation field is significantly perturbed by ongoing magmatic activity in Long Valley. We present a time variable 3D deformation field constrained by InSAR and GPS observations, and discuss the implications that tectonic-magmatic interaction have for estimates of present-day fault slip-rate. We model the time dependent deformation at Long Valley by analyzing InSAR time series from Envisat and ERS interferograms spanning a period of more than 19 years. We use an analytical volcano deformation source model derived from vertical (GPS) and line of site (InSAR) component of geodetic observations to estimate the horizontal component of the signals associated with magmatic activity beneath the caldera. Previous studies showed that the latest episode of uplift can be modeled with a Mogi source located at a depth of ~6 km with a volume change of 0.03 km3 beneath the resurgent dome. This model predicts a perturbation to the ambient crustal deformation field extending as far as 60 km from the center of the resurgent dome. Thus the area affected by Long Valley extends from north of Mono Lake southward to Owens Lake, and eastward to the Mina deflection of the Walker Lane, potentially influencing the estimated slip rates for a dozen or more major faults.

Hydrogeologic framework and estimates of ground-water volumes in Tertiary and upper Cretaceous hydrogeologic units in the Powder River basin, Wyoming

USGS Publications Warehouse

Hinaman, Kurt

2005-01-01

The Powder River Basin in Wyoming and Montana is an important source of energy resources for the United States. Coalbed methane gas is contained in Tertiary and upper Cretaceous hydrogeologic units in the Powder River Basin. This gas is released when water pressure in coalbeds is lowered, usually by pumping ground water. Issues related to disposal and uses of by-product water from coalbed methane production have developed, in part, due to uncertainties in hydrologic properties. One hydrologic property of primary interest is the amount of water contained in Tertiary and upper Cretaceous hydrogeologic units in the Powder River Basin. The U.S. Geological Survey, in cooperation with the Bureau of Land Management, conducted a study to describe the hydrogeologic framework and to estimate ground-water volumes in different facies of Tertiary and upper Cretaceous hydrogeologic units in the Powder River Basin in Wyoming. A geographic information system was used to compile and utilize hydrogeologic maps, to describe the hydrogeologic framework, and to estimate the volume of ground water in Tertiary and upper Cretaceous hydrogeologic units in the Powder River structural basin in Wyoming. Maps of the altitudes of potentiometric surfaces, altitudes of the tops and bottoms of hydrogeologic units, thicknesses of hydrogeologic units, percent sand of hydrogeologic units, and outcrop boundaries for the following hydrogeologic units were used: Tongue River-Wasatch aquifer, Lebo confining unit, Tullock aquifer, Upper Hell Creek confining unit, and the Fox Hills-Lower Hell Creek aquifer. Literature porosity values of 30 percent for sand and 35 percent for non-sand facies were used to calculate the volume of total ground water in each hydrogeologic unit. Literature specific yield values of 26 percent for sand and 10 percent for non-sand facies, and literature specific storage values of 0.0001 ft-1 (1/foot) for sand facies and 0.00001 ft-1 for non-sand facies, were used to calculate a second volume of ground water for each hydrogeologic unit. Significant figure considerations limited estimates of ground-water volumes to two significant digits. A total ground-water volume of 2.0x1014 ft3 (cubic feet) was calculated using porosity values, and a total ground-water volume of 3.6x1013 ft3 was calculated using specific yield and specific storage values. These results are consistent with retention properties, which would have some of the total water being retained in the sediments. Sensitivity analysis shows that the estimates of ground-water volume are most sensitive to porosity. The estimates also are sensitive to confined thickness and saturated thickness. Better spatial information for hydrogeologic units could help refine the ground-water volume estimates.

A meta-analysis of lymph node metastasis rate for patients with thoracic oesophageal cancer and its implication in delineation of clinical target volume for radiation therapy

PubMed Central

Ding, X; Zhang, J; Li, B; Wang, Z; Huang, W; Zhou, T; Wei, Y; Li, H

2012-01-01

Objectives The objective of this study was to pool the lymph node metastasis rate (LNMR) in patients with thoracic oesophageal cancer (TOC) and to determine which node level should be included when undergoing radiation therapy. Methods Qualified studies were identified on Medline, Embase, CBM and the Cochrane Library through to the end of April 2011. Pooled estimates of LNMR were obtained through a random-effect model. Possible effect modifiers which might lead to the statistical heterogeneity were identified through meta-regression, and further subgroup analyses of factors influencing LNMR were performed. Results 45 observational studies with a total of 18 415 patients were included in the meta-analysis. The pooled estimates of LNMR in upper, middle and lower TOC were 30.7%, 16.8% and 11.0% cervical, 42.0%, 21.1% and 10.5% upper mediastinal, 12.9%, 28.1% and 19.6% middle mediastinal, 2.6%, 7.8% and 23.0% lower mediastinal, and 9%, 21.4% and 39.9% abdominal, respectively. Lymph node metastasis most frequently happened to paratracheal, paraoesophageal, perigastric 106recR and station 7. The most obvious difference (≥15%) of LNMR between two-field and three-field lymphatic dissection occurred in cervical, paratracheal, 106recR and 108. Conclusions Through the meta-analysis, more useful information was obtained about clinical target volume (CTV) delineation of TOC patients treated with radiotherapy. However, our study is predominantly a description of squamous carcinoma and the results may not be valid for adenocarcinoma. PMID:22700258

Alcohol consumption and burden of disease in the Americas in 2012: implications for alcohol policy.

PubMed

Shield, Kevin D; Monteiro, Maristela; Roerecke, Michael; Smith, Blake; Rehm, Jürgen

2015-12-01

To describe the volume and patterns of alcohol consumption up to and including 2012, and to estimate the burden of disease attributable to alcohol consumption as measured in deaths and disability-adjusted life years (DALYs) lost in the Americas in 2012. Measures of alcohol consumption were obtained from the World Health Organization (WHO) Global Information System on Alcohol and Health (GISAH). The burden of alcohol consumption was estimated in both deaths and DALYs lost based on mortality data obtained from WHO, using alcohol-attributable fractions. Regional groupings for the Americas were based on the WHO classifications for 2004 (according to child and adult mortality). Regional variations were observed in the overall volume of alcohol consumed, the proportion of the alcohol market attributable to unrecorded alcohol consumption, drinking patterns, prevalence of drinking, and prevalence of heavy episodic drinking, with inhabitants of the Americas consuming more alcohol (8.4 L of pure alcohol per adult in 2012) compared to the world average. The Americas also experienced a high burden of disease attributable to alcohol consumption (4.7% of all deaths and 6.7% of all DALYs lost), especially in terms of injuries attributable to alcohol consumption. Alcohol is consumed in a harmful manner in the Americas, leading to a high burden of disease, especially in terms of injuries. New cost-effective alcohol policies, such as increasing alcohol taxation, increasing the minimum legal age to purchase alcohol, and decreasing the maximum legal blood alcohol content while driving, should be implemented to decrease the harmful consumption of alcohol and the resulting burden of disease.

Impact of routine episodic emissions on the expected frequency distribution of emissions from oil and gas production sources.

NASA Astrophysics Data System (ADS)

Smith, N.; Blewitt, D.; Hebert, L. B.

2015-12-01

In coordination with oil and gas operators, we developed a high resolution (< 1 min) simulation of temporal variability in well-pad oil and gas emissions over a year. We include routine emissions from condensate tanks, dehydrators, pneumatic devices, fugitive leaks and liquids unloading. We explore the variability in natural gas emissions from these individual well-pad sources, and find that routine short-term episodic emissions such as tank flashing and liquids unloading result in the appearance of a skewed, or 'fat-tail' distribution of emissions, from an individual well-pad over time. Additionally, we explore the expected variability in emissions from multiple wells with different raw gas composition, gas/liquids production volumes and control equipment. Differences in well-level composition, production volume and control equipment translate into differences in well-level emissions leading to a fat-tail distribution of emissions in the absence of operational upsets. Our results have several implications for recent studies focusing on emissions from oil and gas sources. Time scale of emission estimates are important and have important policy implications. Fat tail distributions may not be entirely driven by avoidable mechanical failures, and are expected to occur under routine operational conditions from short-duration emissions (e.g., tank flashing, liquid unloading). An understanding of the expected distribution of emissions for a particular population of wells is necessary to evaluate whether the observed distribution is more skewed than expected. Temporal variability in well-pad emissions make comparisons to annual average emissions inventories difficult and may complicate the interpretation of long-term ambient fenceline monitoring data. Sophisticated change detection algorithms will be necessary to identify when true operational upsets occur versus routine short-term emissions.

A Monte Carlo study of the impact of the choice of rectum volume definition on estimates of equivalent uniform doses and the volume parameter

NASA Astrophysics Data System (ADS)

Kvinnsland, Yngve; Muren, Ludvig Paul; Dahl, Olav

2004-08-01

Calculations of normal tissue complication probability (NTCP) values for the rectum are difficult because it is a hollow, non-rigid, organ. Finding the true cumulative dose distribution for a number of treatment fractions requires a CT scan before each treatment fraction. This is labour intensive, and several surrogate distributions have therefore been suggested, such as dose wall histograms, dose surface histograms and histograms for the solid rectum, with and without margins. In this study, a Monte Carlo method is used to investigate the relationships between the cumulative dose distributions based on all treatment fractions and the above-mentioned histograms that are based on one CT scan only, in terms of equivalent uniform dose. Furthermore, the effect of a specific choice of histogram on estimates of the volume parameter of the probit NTCP model was investigated. It was found that the solid rectum and the rectum wall histograms (without margins) gave equivalent uniform doses with an expected value close to the values calculated from the cumulative dose distributions in the rectum wall. With the number of patients available in this study the standard deviations of the estimates of the volume parameter were large, and it was not possible to decide which volume gave the best estimates of the volume parameter, but there were distinct differences in the mean values of the values obtained.

A PILOT STUDY TO DETERMINE THE WATER VOLUME INJESTED BY RECREATIONAL SWIMMERS

EPA Science Inventory

The volume of water ingested by recreational swimmers is unknown. Previous estimates by a number of investigators range from 10mL to 100mL. These estimates, however, are unsupported by empirical data. Many outdoor swimming pools are disinfected using cyanuric acid stabilized c...

Comparison of standing volume estimates using optical dendrometers

Treesearch

Neil A. Clark; Stanley J. Zarnoch; Alexander Clark; Gregory A. Reams

2001-01-01

This study compared height and diameter measurements and volume estimates on 20 hardwood and 20 softwood stems using traditional optical dendrometers, an experimental camera instrument, and mechanical calipers. Multiple comparison tests showed significant differences among the means for lower stem diameters when the camera was used. There were no significant...

Comparison of Standing Volume Estimates Using Optical Dendrometers

Treesearch

Neil A. Clark; Stanley J. Zarnoch; Alexander Clark; Gregory A. Reams

2001-01-01

This study compared height and diameter measurements and volume estimates on 20 hardwood and 20 softwood stems using traditional optical dendrometers, an experimental camera instrument, and mechanical calipers. Multiple comparison tests showed significant differences among the means for lower stem diameters when the camera was used. There were no significant...

Estimating merchantable tree volume in Oregon and Washington using stem profile models

Treesearch

Raymond L. Czaplewski; Amy S. Brown; Dale G. Guenther

1989-01-01

The profile model of Max and Burkhart was fit to eight tree species in the Pacific Northwest Region (Oregon and Washington) of the Forest Service. Most estimates of merchantable volume had an average error less than 10% when applied to independent test data for three national forests.

Measurement variability error for estimates of volume change

Treesearch

James A. Westfall; Paul L. Patterson

2007-01-01

Using quality assurance data, measurement variability distributions were developed for attributes that affect tree volume prediction. Random deviations from the measurement variability distributions were applied to 19381 remeasured sample trees in Maine. The additional error due to measurement variation and measurement bias was estimated via a simulation study for...

Single-dose volume regulation algorithm for a gas-compensated intrathecal infusion pump.

PubMed

Nam, Kyoung Won; Kim, Kwang Gi; Sung, Mun Hyun; Choi, Seong Wook; Kim, Dae Hyun; Jo, Yung Ho

2011-01-01

The internal pressures of medication reservoirs of gas-compensated intrathecal medication infusion pumps decrease when medication is discharged, and these discharge-induced pressure drops can decrease the volume of medication discharged. To prevent these reductions, the volumes discharged must be adjusted to maintain the required dosage levels. In this study, the authors developed an automatic control algorithm for an intrathecal infusion pump developed by the Korean National Cancer Center that regulates single-dose volumes. The proposed algorithm estimates the amount of medication remaining and adjusts control parameters automatically to maintain single-dose volumes at predetermined levels. Experimental results demonstrated that the proposed algorithm can regulate mean single-dose volumes with a variation of <3% and estimate the remaining medication volume with an accuracy of >98%. © 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Segment-specific resistivity improves body fluid volume estimates from bioimpedance spectroscopy in hemodialysis patients.

PubMed

Zhu, F; Kuhlmann, M K; Kaysen, G A; Sarkar, S; Kaitwatcharachai, C; Khilnani, R; Stevens, L; Leonard, E F; Wang, J; Heymsfield, S; Levin, N W

2006-02-01

Discrepancies in body fluid estimates between segmental bioimpedance spectroscopy (SBIS) and gold-standard methods may be due to the use of a uniform value of tissue resistivity to compute extracellular fluid volume (ECV) and intracellular fluid volume (ICV). Discrepancies may also arise from the exclusion of fluid volumes of hands, feet, neck, and head from measurements due to electrode positions. The aim of this study was to define the specific resistivity of various body segments and to use those values for computation of ECV and ICV along with a correction for unmeasured fluid volumes. Twenty-nine maintenance hemodialysis patients (16 men) underwent body composition analysis including whole body MRI, whole body potassium (40K) content, deuterium, and sodium bromide dilution, and segmental and wrist-to-ankle bioimpedance spectroscopy, all performed on the same day before a hemodialysis. Segment-specific resistivity was determined from segmental fat-free mass (FFM; by MRI), hydration status of FFM (by deuterium and sodium bromide), tissue resistance (by SBIS), and segment length. Segmental FFM was higher and extracellular hydration of FFM was lower in men compared with women. Segment-specific resistivity values for arm, trunk, and leg all differed from the uniform resistivity used in traditional SBIS algorithms. Estimates for whole body ECV, ICV, and total body water from SBIS using segmental instead of uniform resistivity values and after adjustment for unmeasured fluid volumes of the body did not differ significantly from gold-standard measures. The uniform tissue resistivity values used in traditional SBIS algorithms result in underestimation of ECV, ICV, and total body water. Use of segmental resistivity values combined with adjustment for body volumes that are neglected by traditional SBIS technique significantly improves estimations of body fluid volume in hemodialysis patients.

Using stereo satellite imagery to account for ablation, entrainment, and compaction in volume calculations for rock avalanches on Glaciers: Application to the 2016 Lamplugh Rock Avalanche in Glacier Bay National Park, Alaska

USGS Publications Warehouse

Bessette-Kirton, Erin; Coe, Jeffrey A.; Zhou, Wendy

2018-01-01

The use of preevent and postevent digital elevation models (DEMs) to estimate the volume of rock avalanches on glaciers is complicated by ablation of ice before and after the rock avalanche, scour of material during rock avalanche emplacement, and postevent ablation and compaction of the rock avalanche deposit. We present a model to account for these processes in volume estimates of rock avalanches on glaciers. We applied our model by calculating the volume of the 28 June 2016 Lamplugh rock avalanche in Glacier Bay National Park, Alaska. We derived preevent and postevent 2‐m resolution DEMs from WorldView satellite stereo imagery. Using data from DEM differencing, we reconstructed the rock avalanche and adjacent surfaces at the time of occurrence by accounting for elevation changes due to ablation and scour of the ice surface, and postevent deposit changes. We accounted for uncertainties in our DEMs through precise coregistration and an assessment of relative elevation accuracy in bedrock control areas. The rock avalanche initially displaced 51.7 ± 1.5 Mm3 of intact rock and then scoured and entrained 13.2 ± 2.2 Mm3 of snow and ice during emplacement. We calculated the total deposit volume to be 69.9 ± 7.9 Mm3. Volume estimates that did not account for topographic changes due to ablation, scour, and compaction underestimated the deposit volume by 31.0–46.8 Mm3. Our model provides an improved framework for estimating uncertainties affecting rock avalanche volume measurements in glacial environments. These improvements can contribute to advances in the understanding of rock avalanche hazards and dynamics.

Form-class volume tables for estimating board-foot content of northern conifers

Treesearch

C. Allen Bickford

1951-01-01

The timber cruiser counts volume tables among his most important working tools. He wants - if he can get them - tables that are simple, easy to use, and accurate. Before using a volume table in a new situation, the careful cruiser will check it by comparing table volumes with actual volumes.

Estimation of standard liver volume in Chinese adult living donors.

PubMed

Fu-Gui, L; Lu-Nan, Y; Bo, L; Yong, Z; Tian-Fu, W; Ming-Qing, X; Wen-Tao, W; Zhe-Yu, C

2009-12-01

To determine a formula predicting the standard liver volume based on body surface area (BSA) or body weight in Chinese adults. A total of 115 consecutive right-lobe living donors not including the middle hepatic vein underwent right hemi-hepatectomy. No organs were used from prisoners, and no subjects were prisoners. Donor anthropometric data including age, gender, body weight, and body height were recorded prospectively. The weights and volumes of the right lobe liver grafts were measured at the back table. Liver weights and volumes were calculated from the right lobe graft weight and volume obtained at the back table, divided by the proportion of the right lobe on computed tomography. By simple linear regression analysis and stepwise multiple linear regression analysis, we correlated calculated liver volume and body height, body weight, or body surface area. The subjects had a mean age of 35.97 +/- 9.6 years, and a female-to-male ratio of 60:55. The mean volume of the right lobe was 727.47 +/- 136.17 mL, occupying 55.59% +/- 6.70% of the whole liver by computed tomography. The volume of the right lobe was 581.73 +/- 96.137 mL, and the estimated liver volume was 1053.08 +/- 167.56 mL. Females of the same body weight showed a slightly lower liver weight. By simple linear regression analysis and stepwise multiple linear regression analysis, a formula was derived based on body weight. All formulae except the Hong Kong formula overestimated liver volume compared to this formula. The formula of standard liver volume, SLV (mL) = 11.508 x body weight (kg) + 334.024, may be applied to estimate liver volumes in Chinese adults.

Methods to enhance seismic faults and construct fault surfaces

NASA Astrophysics Data System (ADS)

Wu, Xinming; Zhu, Zhihui

2017-10-01

Faults are often apparent as reflector discontinuities in a seismic volume. Numerous types of fault attributes have been proposed to highlight fault positions from a seismic volume by measuring reflection discontinuities. These attribute volumes, however, can be sensitive to noise and stratigraphic features that are also apparent as discontinuities in a seismic volume. We propose a matched filtering method to enhance a precomputed fault attribute volume, and simultaneously estimate fault strikes and dips. In this method, a set of efficient 2D exponential filters, oriented by all possible combinations of strike and dip angles, are applied to the input attribute volume to find the maximum filtering responses at all samples in the volume. These maximum filtering responses are recorded to obtain the enhanced fault attribute volume while the corresponding strike and dip angles, that yield the maximum filtering responses, are recoded to obtain volumes of fault strikes and dips. By doing this, we assume that a fault surface is locally planar, and a 2D smoothing filter will yield a maximum response if the smoothing plane coincides with a local fault plane. With the enhanced fault attribute volume and the estimated fault strike and dip volumes, we then compute oriented fault samples on the ridges of the enhanced fault attribute volume, and each sample is oriented by the estimated fault strike and dip. Fault surfaces can be constructed by directly linking the oriented fault samples with consistent fault strikes and dips. For complicated cases with missing fault samples and noisy samples, we further propose to use a perceptual grouping method to infer fault surfaces that reasonably fit the positions and orientations of the fault samples. We apply these methods to 3D synthetic and real examples and successfully extract multiple intersecting fault surfaces and complete fault surfaces without holes.

Risk analysis and guidelines for harvest activities in wisconsin oak timberlands to minimize oak wilt threat

Treesearch

Jennifer Juzwik; Jane Cummings-Carlson; Kyoko Scanlon

2010-01-01

Oaks (Quercus spp.) are an important species group in the forests of Wisconsin. The State’s timberland typed as oak-hickory forest was estimated at 2.9 million acres in 1996. Growing stock volume for red oak was estimated at 2.4 billion cubic feet, whereas select white oak volume was estimated to be 927 million cubic feet. Oak wilt, the oak disease...

Estimation of the rain signal in the presence of large surface clutter

NASA Technical Reports Server (NTRS)

Ahamad, Atiq; Moore, Richard K.

1994-01-01

The principal limitation for the use of a spaceborne imaging SAR as a rain radar is the surface-clutter problem. Signals may be estimated in the presence of noise by averaging large numbers of independent samples. This method was applied to obtain an estimate of the rain echo by averaging a set of N(sub c) samples of the clutter in a separate measurement and subtracting the clutter estimate from the combined estimate. The number of samples required for successful estimation (within 10-20%) for off-vertical angles of incidence appears to be prohibitively large. However, by appropriately degrading the resolution in both range and azimuth, the required number of samples can be obtained. For vertical incidence, the number of samples required for successful estimation is reasonable. In estimating the clutter it was assumed that the surface echo is the same outside the rain volume as it is within the rain volume. This may be true for the forest echo, but for convective storms over the ocean the surface echo outside the rain volume is very different from that within. It is suggested that the experiment be performed with vertical incidence over forest to overcome this limitation.

Ethics and Engineering. Working Papers Series Volume 2.

ERIC Educational Resources Information Center

Cutcliffe, Stephen H., Ed.

This collection of essays is the second volume in a series of working papers from Lehigh University Technology Studies Resource Center. The papers focus on the ethical implications of engineering as a profession and the current problems associated with the public responsibility of engineers. Issues that relate to the ethical dimensions of…

New Trends in Biology Teaching. Volume II.

ERIC Educational Resources Information Center

Heller, R.

The papers presented in this second volume were either written specially for it, or were published in leading biology teaching periodicals of the world in 1966 and 1967. The first section deals with the principles of biology teaching, its purpose, its implication in everyday life, and the social responsibilities of its teachers. The second section…

Studies in Mathematics Education, Volume 3. The Mathematical Education of Primary-School Teachers.

ERIC Educational Resources Information Center

Morris, Robert, Ed.

Recognizing that the teacher is the key to improving any mathematics program, this volume examines the responsibility of primary school teachers for the mathematics component of the curriculum and the implications thereof for teacher education. The first two chapters focus on the responsibilities of teachers of primary mathematics and contemporary…

Personality, Stress, and Coping: Implications for Education. Research on Stress and Coping in Education

ERIC Educational Resources Information Center

Reevy, Gretchen M., Ed.; Frydenberg, Erica, Ed.

2011-01-01

Nearly all chapters in this volume are contemporary original research on personality, stress, and coping in educational contexts. The research spans primary, secondary, and tertiary education. Research participants are students and teachers. The volume brings together contributions from the United States, Australia, Canada, Italy, Scotland, and…

Haines Board: A Review of Army School System for Officer Education and Training. USAIS Position. Volume 1 and Factual Data. Volume 2

DTIC Science & Technology

1965-07-01

currently not suitable for general publica - tion, but which, because of their implication in the future, merit the atten- tion of senior Infantry...OC selection and evaluation, sug- gestions on departmental organization, evaluation of officer students, course prerequisites, attrition

Piezo1 links mechanical forces to red blood cell volume

PubMed Central

Cahalan, Stuart M; Lukacs, Viktor; Ranade, Sanjeev S; Chien, Shu; Bandell, Michael; Patapoutian, Ardem

2015-01-01

Red blood cells (RBCs) experience significant mechanical forces while recirculating, but the consequences of these forces are not fully understood. Recent work has shown that gain-of-function mutations in mechanically activated Piezo1 cation channels are associated with the dehydrating RBC disease xerocytosis, implicating a role of mechanotransduction in RBC volume regulation. However, the mechanisms by which these mutations result in RBC dehydration are unknown. In this study, we show that RBCs exhibit robust calcium entry in response to mechanical stretch and that this entry is dependent on Piezo1 expression. Furthermore, RBCs from blood-cell-specific Piezo1 conditional knockout mice are overhydrated and exhibit increased fragility both in vitro and in vivo. Finally, we show that Yoda1, a chemical activator of Piezo1, causes calcium influx and subsequent dehydration of RBCs via downstream activation of the KCa3.1 Gardos channel, directly implicating Piezo1 signaling in RBC volume control. Therefore, mechanically activated Piezo1 plays an essential role in RBC volume homeostasis. DOI: http://dx.doi.org/10.7554/eLife.07370.001 PMID:26001274

You save money when you buy in bulk: does volume-based pricing cause people to buy more beer?

PubMed

Bray, Jeremy W; Loomis, Brett R; Engelen, Mark

2009-05-01

This paper uses supermarket scanner data to estimate brand- and packaging-specific own- and cross-price elasticities for beer. We find that brand- and packaging-specific beer sales are highly price elastic. Cross-price elasticity estimates suggest that individuals are more likely to buy a higher-volume package of the same brand of beer than they are to switch brands. Policy simulations suggest that regulation of volume-based price discounts is potentially more effective than a tax increase at reducing beer consumption. Our results suggest that volume-based price discounting induces people to buy larger-volume packages of beer and may lead to an increased overall beer consumption. (c) 2008 John Wiley & Sons, Ltd.

A glimpse beneath Antarctic sea ice: observation of platelet-layer thickness and ice-volume fraction with multifrequency EM

NASA Astrophysics Data System (ADS)

Hoppmann, Mario; Hunkeler, Priska A.; Hendricks, Stefan; Kalscheuer, Thomas; Gerdes, Rüdiger

2016-04-01

In Antarctica, ice crystals (platelets) form and grow in supercooled waters below ice shelves. These platelets rise, accumulate beneath nearby sea ice, and subsequently form a several meter thick, porous sub-ice platelet layer. This special ice type is a unique habitat, influences sea-ice mass and energy balance, and its volume can be interpreted as an indicator of the health of an ice shelf. Although progress has been made in determining and understanding its spatio-temporal variability based on point measurements, an investigation of this phenomenon on a larger scale remains a challenge due to logistical constraints and a lack of suitable methodology. In the present study, we applied a lateral constrained Marquardt-Levenberg inversion to a unique multi-frequency electromagnetic (EM) induction sounding dataset obtained on the ice-shelf influenced fast-ice regime of Atka Bay, eastern Weddell Sea. We adapted the inversion algorithm to incorporate a sensor specific signal bias, and confirmed the reliability of the algorithm by performing a sensitivity study using synthetic data. We inverted the field data for sea-ice and platelet-layer thickness and electrical conductivity, and calculated ice-volume fractions within the platelet layer using Archie's Law. The thickness results agreed well with drillhole validation datasets within the uncertainty range, and the ice-volume fraction yielded results comparable to other studies. Both parameters together enable an estimation of the total ice volume within the platelet layer, which was found to be comparable to the volume of landfast sea ice in this region, and corresponded to more than a quarter of the annual basal melt volume of the nearby Ekström Ice Shelf. Our findings show that multi-frequency EM induction sounding is a suitable approach to efficiently map sea-ice and platelet-layer properties, with important implications for research into ocean/ice-shelf/sea-ice interactions. However, a successful application of this technique requires a break with traditional EM sensor calibration strategies due to the need of absolute calibration with respect to a physical forward model.

Wastage of standardised parenteral nutrition solution - a challenge for neonatal units.

PubMed

Deshmukh, Mangesh; Grzejszczyk, Jessica; Mehta, Shailender; Patole, Sanjay

2018-04-01

Standardised parental nutrition (PN) has been used in many neonatal intensive care unit (NICU). Easy accessibility, better provision of nutrients, reduced prescription errors and cost savings are some of its benefits. Fixed large volume (e.g. 750-1000 mL) and short expiry limit (48 hrs) along with changing metabolic needs of neonates leads to significant wastage of PN solution. To evaluate wastage of PN solution in our 22-bedded NICU. The audit was conducted over 21-month period (July 2015-April 2017). Data on PN use (e.g. type, duration, infused volume, residual after use) was obtained from hospital records. The discarded volume of PN was estimated after subtracting the administered volume based on the rate of infusion from the total volume in the bag. Cumulative "discarded" volume as percentage of the total "supplied" volume was calculated. A total of 305-PN bags (Standardised: Preterm: 222, Term: 83) were used. The estimated total used, discarded, and percentage discarded volumes for standard preterm and term PN were 78.1, 88 L, 53% and 33.5, 49.7 L, and 59.8%, respectively. There was more than 50% wastage of PN solution in our NICU. The estimated cost of this PN wastage was around 21,000 AUD over 21 months. Strategies such as minipack should be explored to prevent such losses.

Educational Implications of Technological Change. Technology and the American Economy, Appendix, Volume IV.

ERIC Educational Resources Information Center

National Commission on Technology, Automation and Economic Progress, Washington, DC.

Three studies dealing with the educational implications of technological change are presented. "The Application of Computer Technology to the Improvement of Instruction and Learning" by Don D. Bushnell, Richard deMille, and Judith Purl is based on 35 research and development programs involving computer technology. Their general thesis is that…

Health Implications of Smokeless Tobacco Use. Volume 6, Number 1.

ERIC Educational Resources Information Center

National Institutes of Health (DHHS), Bethesda, MD. Office of Medical Applications of Research.

Concerned with the increase in use of chewing tobacco and snuff, this brochure looks at the health risks of using smokeless tobacco. It presents five questions about smokeless tobacco use and provides answers to the questions developed by a consensus development conference on health implications of smokeless tobacco use convened by the National…

Structural connectivity of neural reward networks in youth at risk for substance use disorders.

PubMed

Squeglia, Lindsay M; Sorg, Scott F; Jacobus, Joanna; Brumback, Ty; Taylor, Charles T; Tapert, Susan F

2015-07-01

Having a positive family history of alcohol use disorders (FHP), as well as aberrant reward circuitry, has been implicated in the initiation of substance use during adolescence. This study explored the relationship between FHP status and reward circuitry in substance naïve youth to better understand future risky behaviors. Participants were 49 FHP and 45 demographically matched family history negative (FHN) substance-naïve 12-14 year-olds (54 % female). Subjects underwent structural magnetic resonance imaging, including diffusion tensor imaging. Nucleus accumbens and orbitofrontal cortex volumes were derived using FreeSurfer, and FSL probabilistic tractography probed structural connectivity and differences in white matter diffusivity estimates (e.g. fractional anisotropy, and mean, radial, and axial diffusivity) between fiber tracts connecting these regions. FHP and FHN youth did not differ on nucleus accumbens or orbitofrontal cortex volumes, white matter tract volumes, or percentages of streamlines (a proxy for fiber tract count) connecting these regions. However, within white matter tracts connecting the nucleus accumbens to the orbitofrontal cortex, FHP youth had significantly lower mean and radial diffusivity (ps < 0.03) than FHN youth. While white matter macrostructure between salience and reward regions did not differ between FHP and FHN youth, FHP youth showed greater white matter coherence within these tracts than FHN youth. Aberrant connectivity between reward regions in FHP youth could be linked to an increased risk for substance use initiation.

Volcanic eruption volume flux estimations from very long period infrasound signals

NASA Astrophysics Data System (ADS)

Yamada, Taishi; Aoyama, Hiroshi; Nishimura, Takeshi; Iguchi, Masato; Hendrasto, Muhamad

2017-01-01

We examine very long period infrasonic signals accompanying volcanic eruptions near active vents at Lokon-Empung volcano in Indonesia, Aso, Kuchinoerabujima, and Kirishima volcanoes in Japan. The excitation of the very long period pulse is associated with an explosion, the emerging of an eruption column, and a pyroclastic density current. We model the excitation of the infrasound pulse, assuming a monopole source, to quantify the volume flux and cumulative volume of erupting material. The infrasound-derived volume flux and cumulative volume can be less than half of the video-derived results. A largely positive correlation can be seen between the infrasound-derived volume flux and the maximum eruption column height. Therefore, our result suggests that the analysis of very long period volcanic infrasound pulses can be helpful in estimating the maximum eruption column height.

Recent numerical and algorithmic advances within the volume tracking framework for modeling interfacial flows

DOE PAGES

François, Marianne M.

2015-05-28

A review of recent advances made in numerical methods and algorithms within the volume tracking framework is presented. The volume tracking method, also known as the volume-of-fluid method has become an established numerical approach to model and simulate interfacial flows. Its advantage is its strict mass conservation. However, because the interface is not explicitly tracked but captured via the material volume fraction on a fixed mesh, accurate estimation of the interface position, its geometric properties and modeling of interfacial physics in the volume tracking framework remain difficult. Several improvements have been made over the last decade to address these challenges.more » In this study, the multimaterial interface reconstruction method via power diagram, curvature estimation via heights and mean values and the balanced-force algorithm for surface tension are highlighted.« less

The Cretaceous Okhotsk-Chukotka Volcanic Belt (NE Russia): Geology, geochronology, magma output rates, and implications on the genesis of silicic LIPs

NASA Astrophysics Data System (ADS)

Tikhomirov, P. L.; Kalinina, E. A.; Moriguti, T.; Makishima, A.; Kobayashi, K.; Cherepanova, I. Yu.; Nakamura, E.

2012-04-01

The Cretaceous Okhotsk-Chukotka volcanic belt (OCVB) is a prominent subduction-related magmatic province, having the remarkably high proportion of silicic rocks (ca. 53% of the present-day crop area, and presumably over 70% of the total volcanic volume). Its estimated total extrusive volume ranges between 5.5 × 105 km3 (the most conservative estimate) and over 106 km3. This article presents a brief outline of the geology of OCVB, yet poorly described in international scientific literature, and results of a geochronological study on the northern part of the volcanic belt. On the base of new and published U-Pb and 40Ar/39Ar age determinations, a new chronological model is proposed. Our study indicates that the activity of the volcanic belt was highly discontinuous and comprised at least five main episodes at 106-98 Ma, 94-91 Ma, 89-87 Ma, 85.5-84 Ma, and 82-79 Ma. The new data allow a semi-quantitative estimate of the volcanic output rate for the observed part of the OCVB (area and volume approximately 105 km2 and 2.5 × 105 km3, respectively). The average extrusion rate for the entire lifetime of the volcanic belt ranges between 1.6 and 3.6 × 10- 5 km3yr- 1 km- 1, depending on the assumed average thickness of the volcanic pile; the optimal value is 2.6 × 10- 5 km3yr- 1 km- 1. Despite imprecise, such estimates infer the time-averaged volcanic productivity of the OCVB is similar to that of silicic LIPs and most active recent subduction-related volcanic areas of the Earth. However, the most extensive volcanic flare-ups at 89-87 and 85.5-84 Ma had higher rates of over 9.0 × 10- 5 km3yr- 1 km- 1. The main volumetric, temporal and compositional parameters of the OCVB are similar to those of silicic LIPs. This gives ground for discussion about the geodynamic setting of the latters, because the widely accepted definition of a LIP implies a strictly intraplate environment. Considering the genesis of the OCVB and other large provinces of silicic volcanism, we propose that residual thermal energy preserved in the continental crust after a previous major magmatic event may have been one of major reasons for high proportion of felsic rocks in a volcanic pile. In this scenario, underplating of mantle-derived basalts causes fast and extensive melting of still hot continental crust and generation of voluminous silicic magmas.

Prognostic Value of Residual Urine Volume, GFR by 24-hour Urine Collection, and eGFR in Patients Receiving Dialysis.

PubMed

Lee, Mi Jung; Park, Jung Tak; Park, Kyoung Sook; Kwon, Young Eun; Oh, Hyung Jung; Yoo, Tae-Hyun; Kim, Yong-Lim; Kim, Yon Su; Yang, Chul Woo; Kim, Nam-Ho; Kang, Shin-Wook; Han, Seung Hyeok

2017-03-07

Residual kidney function can be assessed by simply measuring urine volume, calculating GFR using 24-hour urine collection, or estimating GFR using the proposed equation (eGFR). We aimed to investigate the relative prognostic value of these residual kidney function parameters in patients on dialysis. Using the database from a nationwide prospective cohort study, we compared differential implications of the residual kidney function indices in 1946 patients on dialysis at 36 dialysis centers in Korea between August 1, 2008 and December 31, 2014. Residual GFR calculated using 24-hour urine collection was determined by an average of renal urea and creatinine clearance on the basis of 24-hour urine collection. eGFR-urea, creatinine and eGFR β 2 -microglobulin were calculated from the equations using serum urea and creatinine and β 2 -microglobulin, respectively. The primary outcome was all-cause death. During a mean follow-up of 42 months, 385 (19.8%) patients died. In multivariable Cox analyses, residual urine volume (hazard ratio, 0.96 per 0.1-L/d higher volume; 95% confidence interval, 0.94 to 0.98) and GFR calculated using 24-hour urine collection (hazard ratio, 0.98; 95% confidence interval, 0.95 to 0.99) were independently associated with all-cause mortality. In 1640 patients who had eGFR β 2 -microglobulin data, eGFR β 2 -microglobulin (hazard ratio, 0.98; 95% confidence interval, 0.96 to 0.99) was also significantly associated with all-cause mortality as well as residual urine volume (hazard ratio, 0.96 per 0.1-L/d higher volume; 95% confidence interval, 0.94 to 0.98) and GFR calculated using 24-hour urine collection (hazard ratio, 0.97; 95% confidence interval, 0.95 to 0.99). When each residual kidney function index was added to the base model, only urine volume improved the predictability for all-cause mortality (net reclassification index =0.11, P =0.01; integrated discrimination improvement =0.01, P =0.01). Higher residual urine volume was significantly associated with a lower risk of death and exhibited a stronger association with mortality than GFR calculated using 24-hour urine collection and eGFR-urea, creatinine. These results suggest that determining residual urine volume may be beneficial to predict patient survival in patients on dialysis. Copyright © 2017 by the American Society of Nephrology.

Pharmaco-thermodynamics of deuterium-induced oedema in living rat brain via 1H2O MRI: implications for boron neutron capture therapy of malignant brain tumours

NASA Astrophysics Data System (ADS)

Medina, Daniel C.; Li, Xin; Springer, Charles S., Jr.

2005-05-01

In addition to its common usage as a tracer in metabolic and physiological studies, deuterium possesses anti-tumoural activity and confers protection against γ-irradiation. A more recent interest in deuterium emanates from the search for alternatives capable of improving neutron penetrance whilst reducing healthy tissue radiation dose deposition in boron neutron capture therapy of malignant brain tumours. Despite this potential clinical application, deuterium induces brain oedema, which is detrimental to neutron capture therapy. In this study, five adult male rats were titrated with deuterated drinking water while brain oedema was monitored via water proton magnetic resonance imaging. This report concludes that deuterium, as well as deuterium-induced brain oedema, possesses a uniform brain bio-distribution. At a steady-state blood fluid deuteration value of 16%, when the deuterium isotope fraction in drinking water was 25%, a mean oedematous volume change of 9 ± 2% (p-value <0.001) was observed in the rat brain—this may account for neurological and behavioural abnormalities found in mammals drinking highly deuterated water. In addition to characterizing the pharmaco-thermodynamics of deuterium-induced oedema, this report also estimates the impact of oedema on thermal neutron enhancement and effective dose reduction factors using simple linear transport calculations. While body fluid deuteration enhances thermal neutron flux penetrance and reduces dose deposition, oedema has the opposite effect because it increases the volume of interest, e.g., the brain volume. Thermal neutron enhancement and effective dose reduction factors could be reduced by as much as ~10% in the presence of a 9% water volume increase (oedema). All three authors have contributed equally to this work.

Impact of dose escalation and adaptive radiotherapy for cervical cancers on tumour shrinkage—a modelling study

NASA Astrophysics Data System (ADS)

Røthe Arnesen, Marius; Paulsen Hellebust, Taran; Malinen, Eirik

2017-03-01

Tumour shrinkage occurs during fractionated radiotherapy and is regulated by radiation induced cellular damage, repopulation of viable cells and clearance of dead cells. In some cases additional tumour shrinkage during external beam therapy may be beneficial, particularly for locally advanced cervical cancer where a small tumour volume may simplify and improve brachytherapy. In the current work, a mathematical tumour model is utilized to investigate how local dose escalation affects tumour shrinkage, focusing on implications for brachytherapy. The iterative two-compartment model is based upon linear-quadratic radiation response, a doubling time for viable cells and a half-time for clearance of dead cells. The model was individually fitted to clinical tumour volume data from fractionated radiotherapy of 25 cervical cancer patients. Three different fractionation patterns for dose escalation, all with an additional dose of 12.2 Gy, were simulated and compared to standard fractionation in terms of tumour shrinkage. An adaptive strategy where dose escalation was initiated after one week of treatment was also considered. For 22 out of 25 patients, a good model fit was achieved to the observed tumour shrinkage. A large degree of inter-patient variation was seen in predicted volume reduction following dose escalation. For the 10 best responding patients, a mean tumour volume reduction of 34  ±  3% (relative to standard treatment) was estimated at the time of brachytherapy. Timing of initiating dose escalation had a larger impact than the number of fractions applied. In conclusion, the model was found useful in evaluating the impact from dose escalation on tumour shrinkage. The results indicate that dose escalation could be conducted from the start of external beam radiotherapy in order to obtain additional tumour shrinkage before brachytherapy.

The real estate factor: quantifying the impact of infarct location on stroke severity.

PubMed

Menezes, Nina M; Ay, Hakan; Wang Zhu, Ming; Lopez, Chloe J; Singhal, Aneesh B; Karonen, Jari O; Aronen, Hannu J; Liu, Yawu; Nuutinen, Juho; Koroshetz, Walter J; Sorensen, A Gregory

2007-01-01

The severity of the neurological deficit after ischemic stroke is moderately correlated with infarct volume. In the current study, we sought to quantify the impact of location on neurological deficit severity and to delineate this impact from that of volume. We developed atlases consisting of location-weighted values indicating the relative importance in terms of neurological deficit severity for every voxel of the brain. These atlases were applied to 80 first-ever ischemic stroke patients to produce estimates of clinical deficit severity. Each patient had an MRI and National Institutes of Health Stroke Scale (NIHSS) examination just before or soon after hospital discharge. The correlation between the location-based deficit predictions and measured neurological deficit (NIHSS) scores were compared with the correlation obtained using volume alone to predict the neurological deficit. Volume-based estimates of neurological deficit severity were only moderately correlated with measured NIHSS scores (r=0.62). The combination of volume and location resulted in a significantly better correlation with clinical deficit severity (r=0.79, P=0.032). The atlas methodology is a feasible way of integrating infarct size and location to predict stroke severity. It can estimate stroke severity better than volume alone.

Estimated Minimum Discharge Rates of the Deepwater Horizon Spill-Interim Report to the Flow Rate Technical Group from the Mass Balance Team

USGS Publications Warehouse

Labson, Victor F.; Clark, Roger N.; Swayze, Gregg A.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, K. Eric; Powers, Michael H.; Plumlee, Geoffrey S.; Meeker, Gregory P.

2010-01-01

All of the calculations and results in this report are preliminary and intended for the purpose, and only for the purpose, of aiding the incident team in assessing the extent of the spilled oil for ongoing response efforts. Other applications of this report are not authorized and are not considered valid. Because of time constraints and limitations of data available to the experts, many of their estimates are approximate, are subject to revision, and certainly should not be used as the Federal Government's final values for assessing volume of the spill or its impact to the environment or to coastal communities. Each expert that contributed to this report reserves the right to alter his conclusions based upon further analysis or additional information. An estimated minimum total oil discharge was determined by calculations of oil volumes measured as of May 17, 2010. This included oil on the ocean surface measured with satellite and airborne images and with spectroscopic data (129,000 barrels to 246,000 barrels using less and more aggressive assumptions, respectively), oil skimmed off the surface (23,500 barrels from U.S. Coast Guard [USCG] estimates), oil burned off the surface (11,500 barrels from USCG estimates), dispersed subsea oil (67,000 to 114,000 barrels), and oil evaporated or dissolved (109,000 to 185,000 barrels). Sedimentation (oil captured from Mississippi River silt and deposited on the ocean bottom), biodegradation, and other processes may indicate significant oil volumes beyond our analyses, as will any subsurface volumes such as suspended tar balls or other emulsions that are not included in our estimates. The lower bounds of total measured volumes are estimated to be within the range of 340,000 to 580,000 barrels as of May 17, 2010, for an estimated average minimum discharge rate of 12,500 to 21,500 barrels per day for 27 days from April 20 to May 17, 2010.

Estimating white trunk rot in aspen stands

Treesearch

Alan C. Jones; Michael E. Ostry

1998-01-01

Advanced decay caused by Phellinus tremulae was estimated in 295 trembling aspen on 30 plots in 2 Minnesota counties using existing inventory guides, and then measured by felling and sectioning the trees. In standing trees, decay volume was underestimated by 38% compared to measured decay volume in felled trees. The most reliable external indicator...

An initial abstraction and constant loss model, and methods for estimating unit hydrographs, peak streamflows, and flood volumes for urban basins in Missouri

USGS Publications Warehouse

Huizinga, Richard J.

2014-01-01

The rainfall-runoff pairs from the storm-specific GUH analysis were further analyzed against various basin and rainfall characteristics to develop equations to estimate the peak streamflow and flood volume based on a quantity of rainfall on the basin.

Estimating allowable-cut by area-scheduling

Treesearch

William B. Leak

2011-01-01

Estimation of the regulated allowable-cut is an important step in placing a forest property under management and ensuring a continued supply of timber over time. Regular harvests also provide for the maintenance of needed wildlife habitat. There are two basic approaches: (1) volume, and (2) area/volume regulation, with many variations of each. Some require...

78 FR 71731 - 2014 Standards for the Renewable Fuel Standard Program

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-29

... of E85 Consumption c. Proposed Projection of E85 Consumption in 2014 d. Estimating Total Ethanol Consumption in 2014 2. Estimating Availability of Non-Ethanol Renewable Fuel Volumes a. Non-Ethanol Cellulosic... Biofuel c. Option 3: Availability, Growth, and Limits on Ethanol Consumption D. Summary of Proposed Volume...

Estimating cubic volume of small diameter tree-length logs from ponderosa and lodgepole pine.

Treesearch

Marlin E. Plank; James M. Cahill

1984-01-01

A sample of 351 ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and 509 lodgepole pine (Pinus contorta Dougl. ex Loud.) logs were used to evaluate the performance of three commonly used formulas for estimating cubic volume. Smalian's formula, Bruce's formula, and Huber's formula were tested to determine which...

Estimating outside-bark stem volume to any top diameter for ash in Wisconsin

Treesearch

Paul F. Doruska; Timothy D. Hart

2010-01-01

The future of Wisconsin's estimated 742 million ash trees (5 million of which are in urban settings composing 20 percent of Wisconsin's urban forests) is being considered based on the presence of the emerald ash borer. Part of this discussion includes the stem volumes of these ash trees.

Market projections of cellulose nanomaterial-enabled products- Part 1: Applications

Treesearch

Jo Anne Shatkin; Theodore H. Wegner; E.M. (Ted) Bilek; John Cowie

2014-01-01

Nanocellulose provides a new materials platform for the sustainable production of high-performance nano-enabled products in an array of applications. In this paper, potential applications for cellulose nanomaterials are identified as the first step toward estimating market volume. The overall study, presented in two parts, estimates market volume on the basis of...

Quantifying Contaminant Mass for the Feasibility Study of the DuPont Chambers Works FUSRAP Site - 13510

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

Young, Carl; Rahman, Mahmudur; Johnson, Ann

2013-07-01

The U.S. Army Corps of Engineers (USACE) - Philadelphia District is conducting an environmental restoration at the DuPont Chambers Works in Deepwater, New Jersey under the Formerly Utilized Sites Remedial Action Program (FUSRAP). Discrete locations are contaminated with natural uranium, thorium-230 and radium-226. The USACE is proposing a preferred remedial alternative consisting of excavation and offsite disposal to address soil contamination followed by monitored natural attenuation to address residual groundwater contamination. Methods were developed to quantify the error associated with contaminant volume estimates and use mass balance calculations of the uranium plume to estimate the removal efficiency of the proposedmore » alternative. During the remedial investigation, the USACE collected approximately 500 soil samples at various depths. As the first step of contaminant mass estimation, soil analytical data was segmented into several depth intervals. Second, using contouring software, analytical data for each depth interval was contoured to determine lateral extent of contamination. Six different contouring algorithms were used to generate alternative interpretations of the lateral extent of the soil contamination. Finally, geographical information system software was used to produce a three dimensional model in order to present both lateral and vertical extent of the soil contamination and to estimate the volume of impacted soil for each depth interval. The average soil volume from all six contouring methods was used to determine the estimated volume of impacted soil. This method also allowed an estimate of a standard deviation of the waste volume estimate. It was determined that the margin of error for the method was plus or minus 17% of the waste volume, which is within the acceptable construction contingency for cost estimation. USACE collected approximately 190 groundwater samples from 40 monitor wells. It is expected that excavation and disposal of contaminated soil will remove the contaminant source zone and significantly reduce contaminant concentrations in groundwater. To test this assumption, a mass balance evaluation was performed to estimate the amount of dissolved uranium that would remain in the groundwater after completion of soil excavation. As part of this evaluation, average groundwater concentrations for the pre-excavation and post-excavation aquifer plume area were calculated to determine the percentage of plume removed during excavation activities. In addition, the volume of the plume removed during excavation dewatering was estimated. The results of the evaluation show that approximately 98% of the aqueous uranium would be removed during the excavation phase. The USACE expects that residual levels of contamination will remain in groundwater after excavation of soil but at levels well suited for the selection of excavation combined with monitored natural attenuation as a preferred alternative. (authors)« less

Characterization of Greater-Than-Class C sealed sources. Volume 3, Sealed sources held by general licensees

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

Harris, G.

1994-09-01

This is the third volume in a series of three volumes characterizing the population of sealed sources that may become greater-than-Class C low-level radioactive waste (GTCC LLW). In this volume, those sources possessed by general licensees are discussed. General-licensed devices may contain sealed sources with significant amounts of radioactive material. However, the devices are designed to be safe to use without special knowledge of radiological safety practices. Devices containing Am-241 or Cm-244 sources are most likely to become GTCC LLW after concentration averaging. This study estimates that there are about 16,000 GTCC devices held by general licensees; 15,000 of thesemore » contain Am-241 sources and 1,000 contain Cm-244 sources. Additionally, this study estimates that there are 1,600 GTCC devices sold to general licensees each year. However, due to a lack of available information on general licensees in Agreement States, these estimates are uncertain. This uncertainty is quantified in the low and high case estimates given in this report, which span approximately an order of magnitude.« less

Bounding uncertainty in volumetric geometric models for terrestrial lidar observations of ecosystems.

PubMed

Paynter, Ian; Genest, Daniel; Peri, Francesco; Schaaf, Crystal

2018-04-06

Volumetric models with known biases are shown to provide bounds for the uncertainty in estimations of volume for ecologically interesting objects, observed with a terrestrial laser scanner (TLS) instrument. Bounding cuboids, three-dimensional convex hull polygons, voxels, the Outer Hull Model and Square Based Columns (SBCs) are considered for their ability to estimate the volume of temperate and tropical trees, as well as geomorphological features such as bluffs and saltmarsh creeks. For temperate trees, supplementary geometric models are evaluated for their ability to bound the uncertainty in cylinder-based reconstructions, finding that coarser volumetric methods do not currently constrain volume meaningfully, but may be helpful with further refinement, or in hybridized models. Three-dimensional convex hull polygons consistently overestimate object volume, and SBCs consistently underestimate volume. Voxel estimations vary in their bias, due to the point density of the TLS data, and occlusion, particularly in trees. The response of the models to parametrization is analysed, observing unexpected trends in the SBC estimates for the drumlin dataset. Establishing that this result is due to the resolution of the TLS observations being insufficient to support the resolution of the geometric model, it is suggested that geometric models with predictable outcomes can also highlight data quality issues when they produce illogical results.

Bounding uncertainty in volumetric geometric models for terrestrial lidar observations of ecosystems

PubMed Central

Genest, Daniel; Peri, Francesco; Schaaf, Crystal

2018-01-01

Volumetric models with known biases are shown to provide bounds for the uncertainty in estimations of volume for ecologically interesting objects, observed with a terrestrial laser scanner (TLS) instrument. Bounding cuboids, three-dimensional convex hull polygons, voxels, the Outer Hull Model and Square Based Columns (SBCs) are considered for their ability to estimate the volume of temperate and tropical trees, as well as geomorphological features such as bluffs and saltmarsh creeks. For temperate trees, supplementary geometric models are evaluated for their ability to bound the uncertainty in cylinder-based reconstructions, finding that coarser volumetric methods do not currently constrain volume meaningfully, but may be helpful with further refinement, or in hybridized models. Three-dimensional convex hull polygons consistently overestimate object volume, and SBCs consistently underestimate volume. Voxel estimations vary in their bias, due to the point density of the TLS data, and occlusion, particularly in trees. The response of the models to parametrization is analysed, observing unexpected trends in the SBC estimates for the drumlin dataset. Establishing that this result is due to the resolution of the TLS observations being insufficient to support the resolution of the geometric model, it is suggested that geometric models with predictable outcomes can also highlight data quality issues when they produce illogical results. PMID:29503722

Molar axis estimation from computed tomography images.

PubMed

Dongxia Zhang; Yangzhou Gan; Zeyang Xia; Xinwen Zhou; Shoubin Liu; Jing Xiong; Guanglin Li

2016-08-01

Estimation of tooth axis is needed for some clinical dental treatment. Existing methods require to segment the tooth volume from Computed Tomography (CT) images, and then estimate the axis from the tooth volume. However, they may fail during estimating molar axis due to that the tooth segmentation from CT images is challenging and current segmentation methods may get poor segmentation results especially for these molars with angle which will result in the failure of axis estimation. To resolve this problem, this paper proposes a new method for molar axis estimation from CT images. The key innovation point is that: instead of estimating the 3D axis of each molar from the segmented volume, the method estimates the 3D axis from two projection images. The method includes three steps. (1) The 3D images of each molar are projected to two 2D image planes. (2) The molar contour are segmented and the contour's 2D axis are extracted in each 2D projection image. Principal Component Analysis (PCA) and a modified symmetry axis detection algorithm are employed to extract the 2D axis from the segmented molar contour. (3) A 3D molar axis is obtained by combining the two 2D axes. Experimental results verified that the proposed method was effective to estimate the axis of molar from CT images.

SU-E-J-12: A New Stereological Method for Tumor Volume Evaluation for Esophageal Cancer

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

Feng, Y; Tianjin Medical University Cancer Institute and Hospital; East Carolina University

2014-06-01

Purpose: Stereological method used to obtain three dimensional quantitative information from two dimensional images is a widely used tool in the study of cells and pathology. But the feasibility of the method for quantitative evaluation of volumes with 3D image data sets for radiotherapy clinical application has not been explored. On the other hand, a quick, easy-to-use and reliable method is highly desired in image-guided-radiotherapy(IGRT) for tumor volume measurement for the assessment of response to treatment. To meet this need, a stereological method for evaluating tumor volumes for esophageal cancer is presented in this abstract. Methods: The stereology method wasmore » optimized by selecting the appropriate grid point distances and sample types. 7 patients with esophageal cancer were selected retrospectively for this study, each having pre and post treatment computed tomography (CT) scans. Stereological measurements were performed for evaluating the gross tumor volume (GTV) changes after radiotherapy and the results was compared with the ones by planimetric measurements. Two independent observers evaluated the reproducibility for volume measurement using the new stereological technique. Results: The intraobserver variation in the GTV volume estimation was 3.42±1.68cm3 (the Wilcoxon matched-pairs test Resultwas Z=−1.726,P=0.084>0.05); the interobserver variation in the GTV volume estimation was 22.40±7.23 cm3 (Z=−3.296,P=0.083>0.05), which showed the consistency in GTV volume calculation with the new method for the same and different users. The agreement level between the results from the two techniques was also evaluated. Difference between the measured GTVs was 20.10±5.35 cm3 (Z=−3.101,P=0.089>0.05). Variation of the measurement results using the two techniques was low and clinically acceptable. Conclusion: The good agreement between stereological and planimetric techniques proves the reliability of the stereological tumor volume estimations. The optimized stereological technique described in this abstract may provide a quick, unbiased and reproducible tool for tumor volume estimation for treatment response assessment. Supported by NSFC (#81041107, #81171342 and #31000784)« less

Verification of aerial photo stand volume tables for southeast Alaska.

Treesearch

Theodore S. Setzer; Bert R. Mead

1988-01-01

Aerial photo volume tables are used in the multilevel sampling system of Alaska Forest Inventory and Analysis. These volume tables are presented with a description of the data base and methods used to construct the tables. Volume estimates compiled from the aerial photo stand volume tables and associated ground-measured values are compared and evaluated.

Estimating water volume stored in the south-eastern Greenland firn aquifer using magnetic-resonance soundings

NASA Astrophysics Data System (ADS)

Legchenko, Anatoly; Miège, Clément; Koenig, Lora S.; Forster, Richard R.; Miller, Olivia; Solomon, D. K.; Schmerr, Nicholas; Montgomery, Lynn; Ligtenberg, Stefan; Brucker, Ludovic

2018-03-01

Recent observations of the Greenland ice sheet show an increase of the area affected by progressive melt of snow and ice, thus resulting in production of the additional meltwater. In 2011, an important storage of meltwater in the firn has been observed in the S-E Greenland. This water does not freeze during the wintertime and forms a perennial firn aquifer. The aquifer spatial extent has been initially monitored with combined ground and airborne radar observations, but these geophysical techniques are not able to inform us on the amount of meltwater stored at depth. In this study, we use the magnetic resonance soundings (MRS) method for estimating the volume of water stored in the Greenland ice sheet firn and mapping its spatial variability. Our study area covers a firn aquifer along a 16-km E-W transect, ranging between elevations of 1520 and 1760 m. In July 2015 and July 2016, we performed MRS measurements that allow estimating the water volume in the studied area as well as the one-year water volume evolution. Water storage is not homogeneous, fluctuating between 0.2 and 2 m3/m2, and contains discontinuities in the hydrodynamic properties. We estimate an average volume of water stored in the firn in 2016 to be 0.76 m3/m2, which corresponds to a 0.76-m-thick layer of bulk water. MRS monitoring reveals that from April 2015 to July 2016 the volume of water stored at the location of our transect increases by about 36%. We found MRS-estimated depth to water in a good agreement with that obtained with the ground penetrating radar (GPR).

Meta-analysis to estimate the load of Leptospira excreted in urine: beyond rats as important sources of transmission in low-income rural communities.

PubMed

Barragan, Veronica; Nieto, Nathan; Keim, Paul; Pearson, Talima

2017-01-28

Leptospirosis is a major zoonotic disease with widespread distribution and a large impact on human health. Carrier animals excrete pathogenic Leptospira primarily in their urine. Infection occurs when the pathogen enters a host through mucosa or small skin abrasions. Humans and other animals are exposed to the pathogen by direct contact with urine, contaminated soil or water. While many factors influence environmental cycling and the transmission of Leptospira to humans, the load of pathogenic Leptospira in the environment is likely to play a major role. Peridomestic rats are often implicated as a potential source of human disease; however exposure to other animals is a risk factor as well. The aim of this report is to highlight the importance of various carrier animals in terms of the quantity of Leptospira shed into the environment. For this, we performed a systematic literature review and a meta-analysis of the amount of pathogen that various animal species shed in their urine. The quantity of pathogen has been reported for cows, deer, dogs, humans, mice, and rats, in a total of 14 research articles. We estimated the average Leptospira per unit volume shed by each animal species, and the daily environmental contribution by considering the total volume of urine excreted by each carrier animal. Rats excrete the highest quantity of Leptospira per millilitre of urine (median = 5.7 × 10 6  cells), but large mammals excrete much more urine and thus shed significantly more Leptospira per day (5.1 × 10 8 to 1.3 × 10 9  cells). Here we illustrate how, in a low-income rural Ecuadorian community, host population demographics, and prevalence of Leptospira infection can be integrated with estimates of shed Leptospira to suggest that peridomestic cattle may be more important than rats in environmental cycling and ultimately, transmission to humans.

Pairing top-down and bottom-up approaches to analyze catchment scale management of water quality and quantity

NASA Astrophysics Data System (ADS)

Lovette, J. P.; Duncan, J. M.; Band, L. E.

2016-12-01

Watershed management requires information on the hydrologic impacts of local to regional land use, land cover and infrastructure conditions. Management of runoff volumes, storm flows, and water quality can benefit from large scale, "top-down" screening tools, using readily available information, as well as more detailed, "bottom-up" process-based models that explicitly track local runoff production and routing from sources to receiving water bodies. Regional scale data, available nationwide through the NHD+, and top-down models based on aggregated catchment information provide useful tools for estimating regional patterns of peak flows, volumes and nutrient loads at the catchment level. Management impacts can be estimated with these models, but have limited ability to resolve impacts beyond simple changes to land cover proportions. Alternatively, distributed process-based models provide more flexibility in modeling management impacts by resolving spatial patterns of nutrient source, runoff generation, and uptake. This bottom-up approach can incorporate explicit patterns of land cover, drainage connectivity, and vegetation extent, but are typically applied over smaller areas. Here, we first model peak flood flows and nitrogen loads across North Carolina's 70,000 NHD+ catchments using USGS regional streamflow regression equations and the SPARROW model. We also estimate management impact by altering aggregated sources in each of these models. To address the missing spatial implications of the top-down approach, we further explore the demand for riparian buffers as a management strategy, simulating the accumulation of nutrient sources along flow paths and the potential mitigation of these sources through forested buffers. We use the Regional Hydro-Ecological Simulation System (RHESSys) to model changes across several basins in North Carolina's Piedmont and Blue Ridge regions, ranging in size from 15 - 1,130 km2. The two approaches provide a complementary set of tools for large area screening, followed by smaller, more process based assessment and design tools.

3D Porosity Estimation of the Nankai Trough Sediments from Core-log-seismic Integration

NASA Astrophysics Data System (ADS)

Park, J. O.

2015-12-01

The Nankai Trough off southwest Japan is one of the best subduction-zone to study megathrust earthquake fault. Historic, great megathrust earthquakes with a recurrence interval of 100-200 yr have generated strong motion and large tsunamis along the Nankai Trough subduction zone. At the Nankai Trough margin, the Philippine Sea Plate (PSP) is being subducted beneath the Eurasian Plate to the northwest at a convergence rate ~4 cm/yr. The Shikoku Basin, the northern part of the PSP, is estimated to have opened between 25 and 15 Ma by backarc spreading of the Izu-Bonin arc. The >100-km-wide Nankai accretionary wedge, which has developed landward of the trench since the Miocene, mainly consists of offscraped and underplated materials from the trough-fill turbidites and the Shikoku Basin hemipelagic sediments. Particularly, physical properties of the incoming hemipelagic sediments may be critical for seismogenic behavior of the megathrust fault. We have carried out core-log-seismic integration (CLSI) to estimate 3D acoustic impedance and porosity for the incoming sediments in the Nankai Trough. For the CLSI, we used 3D seismic reflection data, P-wave velocity and density data obtained during IODP (Integrated Ocean Drilling Program) Expeditions 322 and 333. We computed acoustic impedance depth profiles for the IODP drilling sites from P-wave velocity and density data. We constructed seismic convolution models with the acoustic impedance profiles and a source wavelet which is extracted from the seismic data, adjusting the seismic models to observed seismic traces with inversion method. As a result, we obtained 3D acoustic impedance volume and then converted it to 3D porosity volume. In general, the 3D porosities show decrease with depth. We found a porosity anomaly zone with alteration of high and low porosities seaward of the trough axis. In this talk, we will show detailed 3D porosity of the incoming sediments, and present implications of the porosity anomaly zone for the megathrust fault behavior.

Non-invasive thermal IR detection of breast tumor development in vivo

NASA Astrophysics Data System (ADS)

Case, Jason R.; Young, Madison A.; Dréau, D.; Trammell, Susan R.

2015-03-01

Lumpectomy coupled with radiation therapy and/or chemotherapy comprises the treatment of breast cancer for many patients. We are developing an enhanced thermal IR imaging technique that can be used in real-time to guide tissue excision during a lumpectomy. This novel enhanced thermal imaging method is a combination of IR imaging (8- 10 μm) and selective heating of blood (~0.5 °C) relative to surrounding water-rich tissue using LED sources at low powers. Post-acquisition processing of these images highlights temporal changes in temperature and is sensitive to the presence of vascular structures. In this study, fluorescent and enhanced thermal imaging modalities were used to estimate breast cancer tumor volumes as a function of time in 19 murine subjects over a 30-day study period. Tumor volumes calculated from fluorescent imaging follow an exponential growth curve for the first 22 days of the study. Cell necrosis affected the tumor volume estimates based on the fluorescent images after Day 22. The tumor volumes estimated from enhanced thermal imaging show exponential growth over the entire study period. A strong correlation was found between tumor volumes estimated using fluorescent imaging and the enhanced IR images, indicating that enhanced thermal imaging is capable monitoring tumor growth. Further, the enhanced IR images reveal a corona of bright emission along the edges of the tumor masses. This novel IR technique could be used to estimate tumor margins in real-time during surgical procedures.

Comparison of left and right atrial volume by echocardiography versus cardiac magnetic resonance imaging using the area-length method.

PubMed

Whitlock, Matthew; Garg, Anuj; Gelow, Jill; Jacobson, Timothy; Broberg, Craig

2010-11-01

Increased atrial volumes predict adverse cardiovascular events. Accordingly, accurate measurement of atrial size has become increasingly important in clinical practice. The area-length method is commonly used to estimate the volume. Disagreements between atrial volumes using echocardiography and other imaging modalities have been found. It is unclear whether this has resulted from differences in the measurement method or discrepancies among imaging modalities. We compared the right atrial (RA) and left atrial (LA) volume estimates using the area-length method for transthoracic echocardiography and cardiovascular magnetic resonance (CMR) imaging. Patients undergoing echocardiography and CMR imaging within 1 month were identified retrospectively. For both modalities, the RA and LA long-axis dimension and area were measured using standard 2- and 4-chamber views, and the volume was calculated using the area-length method for both atria. The echocardiographic and CMR values were compared using the Bland-Altman method. A total of 85 patients and 18 controls were included in the present study. The atrial volumes estimated using the area-length method were significantly smaller when measured using echocardiography than when measured using CMR imaging (LA volume 35 ± 20 vs 49 ± 30 ml/m², p <0.001, and RA volume 32 ± 23 vs 43 ± 29 ml/m², p = 0.012). The mean difference (CMR imaging minus echocardiography) was 14 ± 14 ml/m² for the LA and 10 ± 16 ml/m² for the RA volume. Similar results were found in the healthy controls. No significant intra- or interobserver variability was found within each modality. In conclusion, echocardiography consistently underestimated the atrial volumes compared to CMR imaging using the area-length method. Copyright © 2010 Elsevier Inc. All rights reserved.

Modeling Approach for Estimating Co-Produced Water Volumes and Saltwater Disposal Volumes in Oklahoma

NASA Astrophysics Data System (ADS)

Murray, K. E.

2016-12-01

Management of produced fluids has become an important issue in Oklahoma because large volumes of saltwater are co-produced with oil and gas, and disposed into saltwater disposal wells at high rates. Petroleum production increased from 2009-2015, especially in central and north-central Oklahoma where the Mississippian and Hunton zones were redeveloped using horizontal wells and dewatering techniques that have led to a disproportional increase in produced water volumes. Improved management of co-produced water, including desalination for beneficial reuse and decreased saltwater disposal volumes, is only possible if spatial and temporal trends can be defined and related to the producing zones. It is challenging to quantify the volumes of co-produced water by region or production zone because co-produced water volumes are generally not reported. Therefore, the goal of this research is to estimate co-produced water volumes for 2008-present with an approach that can be replicated as petroleum production shifts to other regions. Oil and gas production rates from subsurface zones were multiplied by ratios of H2O:oil and H2O:gas for the respective zones. Initial H2O:oil and H2O:gas ratios were adjusted/calibrated, by zone, to maximize correlation of county-scale produced H2O estimates versus saltwater disposal volumes from 2013-2015. These calibrated ratios were then used to compute saltwater disposal volumes from 2008-2012 because of apparent data gaps in reported saltwater disposal volumes during that timeframe. This research can be used to identify regions that have the greatest need for produced water treatment systems. The next step in management of produced fluids is to explore optimal energy-efficient strategies that reduce deleterious effects.

Radioactive waste from decommissioning of fast reactors (through the example of BN-800)

NASA Astrophysics Data System (ADS)

Rybin, A. A.; Momot, O. A.

2017-01-01

Estimation of volume of radioactive waste from operating and decommissioning of fast reactors is introduced. Preliminary estimation has shown that the volume of RW from decommissioning of BN-800 is amounted to 63,000 cu. m. Comparison of the amount of liquid radioactive waste derived from operation of different reactor types is performed. Approximate costs of all wastes disposal for complete decommissioning of BN-800 reactor are estimated amounting up to approx. 145 million.

Application of the precipitation-runoff modeling system to the Ah- shi-sle-pah Wash watershed, San Juan County, New Mexico

USGS Publications Warehouse

Hejl, H.R.

1989-01-01

The precipitation-runoff modeling system was applied to the 8.21 sq-mi drainage area of the Ah-shi-sle-pah Wash watershed in northwestern New Mexico. The calibration periods were May to September of 1981 and 1982, and the verification period was May to September 1983. Twelve storms were available for calibration and 8 storms were available for verification. For calibration A (hydraulic conductivity estimated from onsite data and other storm-mode parameters optimized), the computed standard error of estimate was 50% for runoff volumes and 72% of peak discharges. Calibration B included hydraulic conductivity in the optimization, which reduced the standard error of estimate to 28 % for runoff volumes and 50% for peak discharges. Optimized values for hydraulic conductivity resulted in reductions from 1.00 to 0.26 in/h and 0.20 to 0.03 in/h for the 2 general soils groups in the calibrations. Simulated runoff volumes using 7 of 8 storms occurring during the verification period had a standard error of estimate of 40% for verification A and 38% for verification B. Simulated peak discharge had a standard error of estimate of 120% for verification A and 56% for verification B. Including the eighth storm which had a relatively small magnitude in the verification analysis more than doubled the standard error of estimating volumes and peaks. (USGS)

The volume of the human knee joint.

PubMed

Matziolis, Georg; Roehner, Eric; Windisch, Christoph; Wagner, Andreas

2015-10-01

Despite its clinical relevance, particularly in septic knee surgery, the volume of the human knee joint has not been established to date. Therefore, the objective of this study was to determine knee joint volume and whether or not it is dependent on sex or body height. Sixty-one consecutive patients (joints) who were due to undergo endoprosthetic joint replacement were enrolled in this prospective study. During the operation, the joint volume was determined by injecting saline solution until a pressure of 200 mmHg was achieved in the joint. The average volume of all knee joints was 131 ± 53 (40-290) ml. The volume was not found to be dependent on sex, but it was dependent on the patients' height (R = 0.312, p = 0.014). This enabled an estimation of the joint volume according to V = 1.6 height - 135. The considerable inter-individual variance of the knee joint volume would suggest that it should be determined or at least estimated according to body height if the joint volume has consequences for the diagnostics or therapy of knee disorders.

Minimally invasive estimation of ventricular dead space volume through use of Frank-Starling curves.

PubMed

Davidson, Shaun; Pretty, Chris; Pironet, Antoine; Desaive, Thomas; Janssen, Nathalie; Lambermont, Bernard; Morimont, Philippe; Chase, J Geoffrey

2017-01-01

This paper develops a means of more easily and less invasively estimating ventricular dead space volume (Vd), an important, but difficult to measure physiological parameter. Vd represents a subject and condition dependent portion of measured ventricular volume that is not actively participating in ventricular function. It is employed in models based on the time varying elastance concept, which see widespread use in haemodynamic studies, and may have direct diagnostic use. The proposed method involves linear extrapolation of a Frank-Starling curve (stroke volume vs end-diastolic volume) and its end-systolic equivalent (stroke volume vs end-systolic volume), developed across normal clinical procedures such as recruitment manoeuvres, to their point of intersection with the y-axis (where stroke volume is 0) to determine Vd. To demonstrate the broad applicability of the method, it was validated across a cohort of six sedated and anaesthetised male Pietrain pigs, encompassing a variety of cardiac states from healthy baseline behaviour to circulatory failure due to septic shock induced by endotoxin infusion. Linear extrapolation of the curves was supported by strong linear correlation coefficients of R = 0.78 and R = 0.80 average for pre- and post- endotoxin infusion respectively, as well as good agreement between the two linearly extrapolated y-intercepts (Vd) for each subject (no more than 7.8% variation). Method validity was further supported by the physiologically reasonable Vd values produced, equivalent to 44.3-53.1% and 49.3-82.6% of baseline end-systolic volume before and after endotoxin infusion respectively. This method has the potential to allow Vd to be estimated without a particularly demanding, specialised protocol in an experimental environment. Further, due to the common use of both mechanical ventilation and recruitment manoeuvres in intensive care, this method, subject to the availability of multi-beat echocardiography, has the potential to allow for estimation of Vd in a clinical environment.

Body composition estimation from selected slices: equations computed from a new semi-automatic thresholding method developed on whole-body CT scans

PubMed Central

Villa, Chiara; Brůžek, Jaroslav

2017-01-01

Background Estimating volumes and masses of total body components is important for the study and treatment monitoring of nutrition and nutrition-related disorders, cancer, joint replacement, energy-expenditure and exercise physiology. While several equations have been offered for estimating total body components from MRI slices, no reliable and tested method exists for CT scans. For the first time, body composition data was derived from 41 high-resolution whole-body CT scans. From these data, we defined equations for estimating volumes and masses of total body AT and LT from corresponding tissue areas measured in selected CT scan slices. Methods We present a new semi-automatic approach to defining the density cutoff between adipose tissue (AT) and lean tissue (LT) in such material. An intra-class correlation coefficient (ICC) was used to validate the method. The equations for estimating the whole-body composition volume and mass from areas measured in selected slices were modeled with ordinary least squares (OLS) linear regressions and support vector machine regression (SVMR). Results and Discussion The best predictive equation for total body AT volume was based on the AT area of a single slice located between the 4th and 5th lumbar vertebrae (L4-L5) and produced lower prediction errors (|PE| = 1.86 liters, %PE = 8.77) than previous equations also based on CT scans. The LT area of the mid-thigh provided the lowest prediction errors (|PE| = 2.52 liters, %PE = 7.08) for estimating whole-body LT volume. We also present equations to predict total body AT and LT masses from a slice located at L4-L5 that resulted in reduced error compared with the previously published equations based on CT scans. The multislice SVMR predictor gave the theoretical upper limit for prediction precision of volumes and cross-validated the results. PMID:28533960

Body composition estimation from selected slices: equations computed from a new semi-automatic thresholding method developed on whole-body CT scans.

PubMed

Lacoste Jeanson, Alizé; Dupej, Ján; Villa, Chiara; Brůžek, Jaroslav

2017-01-01

Estimating volumes and masses of total body components is important for the study and treatment monitoring of nutrition and nutrition-related disorders, cancer, joint replacement, energy-expenditure and exercise physiology. While several equations have been offered for estimating total body components from MRI slices, no reliable and tested method exists for CT scans. For the first time, body composition data was derived from 41 high-resolution whole-body CT scans. From these data, we defined equations for estimating volumes and masses of total body AT and LT from corresponding tissue areas measured in selected CT scan slices. We present a new semi-automatic approach to defining the density cutoff between adipose tissue (AT) and lean tissue (LT) in such material. An intra-class correlation coefficient (ICC) was used to validate the method. The equations for estimating the whole-body composition volume and mass from areas measured in selected slices were modeled with ordinary least squares (OLS) linear regressions and support vector machine regression (SVMR). The best predictive equation for total body AT volume was based on the AT area of a single slice located between the 4th and 5th lumbar vertebrae (L4-L5) and produced lower prediction errors (|PE| = 1.86 liters, %PE = 8.77) than previous equations also based on CT scans. The LT area of the mid-thigh provided the lowest prediction errors (|PE| = 2.52 liters, %PE = 7.08) for estimating whole-body LT volume. We also present equations to predict total body AT and LT masses from a slice located at L4-L5 that resulted in reduced error compared with the previously published equations based on CT scans. The multislice SVMR predictor gave the theoretical upper limit for prediction precision of volumes and cross-validated the results.

A Review of Electrical Impedance Spectrometry Methods for Parametric Estimation of Physiologic Fluid Volumes

NASA Technical Reports Server (NTRS)

Dewberry, B.

2000-01-01

Electrical impedance spectrometry involves measurement of the complex resistance of a load at multiple frequencies. With this information in the form of impedance magnitude and phase, or resistance and reactance, basic structure or function of the load can be estimated. The "load" targeted for measurement and estimation in this study consisted of the water-bearing tissues of the human calf. It was proposed and verified that by measuring the electrical impedance of the human calf and fitting this data to a model of fluid compartments, the lumped-model volume of intracellular and extracellular spaces could be estimated, By performing this estimation over time, the volume dynamics during application of stimuli which affect the direction of gravity can be viewed. The resulting data can form a basis for further modeling and verification of cardiovascular and compartmental modeling of fluid reactions to microgravity as well as countermeasures to the headward shift of fluid during head-down tilt or spaceflight.

Automatic portion estimation and visual refinement in mobile dietary assessment

NASA Astrophysics Data System (ADS)

Woo, Insoo; Otsmo, Karl; Kim, SungYe; Ebert, David S.; Delp, Edward J.; Boushey, Carol J.

2010-01-01

As concern for obesity grows, the need for automated and accurate methods to monitor nutrient intake becomes essential as dietary intake provides a valuable basis for managing dietary imbalance. Moreover, as mobile devices with built-in cameras have become ubiquitous, one potential means of monitoring dietary intake is photographing meals using mobile devices and having an automatic estimate of the nutrient contents returned. One of the challenging problems of the image-based dietary assessment is the accurate estimation of food portion size from a photograph taken with a mobile digital camera. In this work, we describe a method to automatically calculate portion size of a variety of foods through volume estimation using an image. These "portion volumes" utilize camera parameter estimation and model reconstruction to determine the volume of food items, from which nutritional content is then extrapolated. In this paper, we describe our initial results of accuracy evaluation using real and simulated meal images and demonstrate the potential of our approach.

Volumetric evaluation of the relations among the cerebrum, cerebellum and brain stem in young subjects: a combination of stereology and magnetic resonance imaging.

PubMed

Ekinci, Nihat; Acer, Niyazi; Akkaya, Akcan; Sankur, Seref; Kabadayi, Taner; Sahin, Bünyamin

2008-08-01

The Cavalieri estimator using a point grid is used to estimate the volume of three-dimensional structures based on two-dimensional slices of the object. The size of the components of intracranial neural structures should have proportional relations among them. The volume fraction approach of stereological methods provides information about volumetric relations of the components of structures. The purpose of our study is to estimate the volume and volume fraction data related to the cerebrum, cerebellum and brain stem. In this study, volume of the total brain, cerebrum, cerebellum and brain stem were estimated in 24 young Turkish volunteers (12 males and 12 females) who are free of any neurological symptoms and signs. The volume and volume fraction of the total brain, cerebrum, cerebellum and brain stem were determined on magnetic resonance (MR) images using the point-counting approach of stereological methods. The mean (+/-SD) total brain, cerebrum and cerebellum volumes were 1,202.05 +/- 103.51, 1,143.65 +/- 106.25 cm3 in males and females, 1,060.0 +/- 94.6, 1,008.9 +/- 104.3 cm3 in males and females, 117.75 +/- 10.7, 111.83 +/- 8.0 cm3 in males and females, respectively. The mean brain stem volumes were 24.3 +/- 2.89, 22.9 +/- 4.49 cm3 in males and females, respectively. Our results revealed that female subjects have less cerebral, cerebellar and brain stem volumes compared to males, although there was no statistically significant difference between genders (P > 0.05). The volume ratio of the cerebrum to total brain volume (TBV), cerebellum to TBV and brain stem to TBV were 88.16 and 88.13% in males and females, 9.8 and 9.8% in males and females, 2.03 and 2.03% in males and females, respectively. The volume ratio of the cerebellum to cerebrum, brain stem to cerebrum and brain stem to cerebellum were 11.12 and 11.16% in males and females, 2.30 and 2.31% in males and females, 20.7 and 20.6% in males and females, respectively. The difference between the genders was not statistically significant (P > 0.05). Our results revealed that the volumetric composition of the cerebrum, cerebellum and brain stem does not show sexual dimorphism.

An Estimate of Recoverable Heavy Oil Resources of the Orinoco Oil Belt, Venezuela

USGS Publications Warehouse

Schenk, Christopher J.; Cook, Troy A.; Charpentier, Ronald R.; Pollastro, Richard M.; Klett, Timothy R.; Tennyson, Marilyn E.; Kirschbaum, Mark A.; Brownfield, Michael E.; Pitman, Janet K.

2009-01-01

The Orinoco Oil Belt Assessment Unit of the La Luna-Quercual Total Petroleum System encompasses approximately 50,000 km2 of the East Venezuela Basin Province that is underlain by more than 1 trillion barrels of heavy oil-in-place. As part of a program directed at estimating the technically recoverable oil and gas resources of priority petroleum basins worldwide, the U.S. Geological Survey estimated the recoverable oil resources of the Orinoco Oil Belt Assessment Unit. This estimate relied mainly on published geologic and engineering data for reservoirs (net oil-saturated sandstone thickness and extent), petrophysical properties (porosity, water saturation, and formation volume factors), recovery factors determined by pilot projects, and estimates of volumes of oil-in-place. The U.S. Geological Survey estimated a mean volume of 513 billion barrels of technically recoverable heavy oil in the Orinoco Oil Belt Assessment Unit of the East Venezuela Basin Province; the range is 380 to 652 billion barrels. The Orinoco Oil Belt Assessment Unit thus contains one of the largest recoverable oil accumulations in the world.

Anthropometrically estimated total body water volumes are larger than modeled urea volume in chronic hemodialysis patients: effects of age, race, and gender.

PubMed

Daugirdas, John T; Greene, Tom; Depner, Thomas A; Chumlea, Cameron; Rocco, Michael J; Chertow, Glenn M

2003-09-01

The modeled volume of urea distribution (Vm) in intermittently hemodialyzed patients is often compared with total body water (TBW) volume predicted from population studies of patient anthropometrics (Vant). Using data from the HEMO Study, we compared Vm determined by both blood-side and dialysate-side urea kinetic models with Vant as calculated by the Watson, Hume-Weyers, and Chertow anthropometric equations. Median levels of dialysate-based Vm and blood-based Vm agreed (43% and 44% of body weight, respectively). These volumes were lower than anthropometric estimates of TBW, which had median values of 52% to 55% of body weight for the three formulas evaluated. The difference between the Watson equation for TBW and modeled urea volume was greater in Caucasians (19%) than in African Americans (13%). Correlations between Vm and Vant determined by each of the three anthropometric estimation equations were similar; but Vant derived from the Watson formula had a slightly higher correlation with Vm. The difference between Vm and the anthropometric formulas was greatest with the Chertow equation, less with the Hume-Weyers formula, and least with the Watson estimate. The age term in the Watson equation for men that adjusts Vant downward with increasing age reduced an age effect on the difference between Vant and Vm in men. The findings show that kinetically derived values for V from blood-side and dialysate-side modeling are similar, and that these modeled urea volumes are lower by a substantial amount than anthropometric estimates of TBW. The higher values for anthropometry-derived TBW in hemodialyzed patients could be due to measurement errors. However, the possibility exists that TBW space is contracted in patients with end-stage renal disease (ESRD) or that the TBW space and the urea distribution space are not identical.

Sediment Transportation Induced by Deep-Seated Landslides in a Debris Flow Basin in Taiwan

NASA Astrophysics Data System (ADS)

Lin, Meei Ling; Chen, Te Wei; Chen, Yong Sheng; Sin Jhuang, Han

2016-04-01

Typhoon Morakot brought huge amount of rainfall to the southern Taiwan in 2009 and caused severe landslides and debris flow hazard. After Typhoon Morakot, it was found that the volume of sediment transported by the debris flow and its effects on the affected area were much more significant compared to previous case history, which may due to the huge amount of rainfall causing significant deep-seated landslides in the basin. In this study, the effects and tendency of the sediment transportation in a river basin following deep-seated landslides caused by typhoon Morakot were evaluated. We used LiDAR, DEM, and aerial photo to identify characteristics of deep-seated landslides in a debris flow river basin, KSDF079 in Liuoguey District, Kaohsiung City, Taiwan. Eight deep-seated landslides were identified in the basin. To estimate the potential landslide volume associated with the deep-seated landslides, the stability analysis was conducted to locate the critical sliding surface, and the potential landside volume was estimated based on the estimation equation proposed by the International Geotechnical Societies' UNESCO Working Party on World Landslide Inventory (WP/WLI, 1990). The total potential landslide volume of the eight deep-seated landslides in KSDF079 basin was about 28,906,856 m3. Topographic analysis was performed by using DEM before and LiDAR derived DEM after typhoon Morakot to calculate the landslide volume transported. The result of erosion volume and deposition volume lead to a run out volume of 5,832,433 m3. The results appeared to consist well with the field condition and aerial photo. Comparing the potential landslide volume and run out volume of eight deep-seated landslides, it was found that the remaining potential landslide volume was about 80%. Field investigation and topographic analysis of the KSDF079 debris flow revealed that a significant amount of sediment deposition remained in the river channel ranging from the middle to the downstream section of the channel, and the channel has been widen. Such large proportion of landslide volume remained in the basin on deep-seated landslide scars and debris flow river channel would likely to cause further debris transportation in the future events. The stability analysis used in this study provided a feasible method and satisfactory results for estimating sediment volume transportation associated with the deep-seated landslides in the study area. Combination of the stability analysis results and the topographic analysis provided estimation of sediment transportation caused by the deep-seated landslides, and trend variation of further sediment transport of the basin, which could provide vital information for hazard mitigation. Keyword: deep-seated landslide, sediment transport, DEM, LiDAR, stability analysis

Allometric Analysis Detects Brain Size-Independent Effects of Sex and Sex Chromosome Complement on Human Cerebellar Organization.

PubMed

Mankiw, Catherine; Park, Min Tae M; Reardon, P K; Fish, Ari M; Clasen, Liv S; Greenstein, Deanna; Giedd, Jay N; Blumenthal, Jonathan D; Lerch, Jason P; Chakravarty, M Mallar; Raznahan, Armin

2017-05-24

The cerebellum is a large hindbrain structure that is increasingly recognized for its contribution to diverse domains of cognitive and affective processing in human health and disease. Although several of these domains are sex biased, our fundamental understanding of cerebellar sex differences-including their spatial distribution, potential biological determinants, and independence from brain volume variation-lags far behind that for the cerebrum. Here, we harness automated neuroimaging methods for cerebellar morphometrics in 417 individuals to (1) localize normative male-female differences in raw cerebellar volume, (2) compare these to sex chromosome effects estimated across five rare sex (X/Y) chromosome aneuploidy (SCA) syndromes, and (3) clarify brain size-independent effects of sex and SCA on cerebellar anatomy using a generalizable allometric approach that considers scaling relationships between regional cerebellar volume and brain volume in health. The integration of these approaches shows that (1) sex and SCA effects on raw cerebellar volume are large and distributed, but regionally heterogeneous, (2) human cerebellar volume scales with brain volume in a highly nonlinear and regionally heterogeneous fashion that departs from documented patterns of cerebellar scaling in phylogeny, and (3) cerebellar organization is modified in a brain size-independent manner by sex (relative expansion of total cerebellum, flocculus, and Crus II-lobule VIIIB volumes in males) and SCA (contraction of total cerebellar, lobule IV, and Crus I volumes with additional X- or Y-chromosomes; X-specific contraction of Crus II-lobule VIIIB). Our methods and results clarify the shifts in human cerebellar organization that accompany interwoven variations in sex, sex chromosome complement, and brain size. SIGNIFICANCE STATEMENT Cerebellar systems are implicated in diverse domains of sex-biased behavior and pathology, but we lack a basic understanding of how sex differences in the human cerebellum are distributed and determined. We leverage a rare neuroimaging dataset to deconvolve the interwoven effects of sex, sex chromosome complement, and brain size on human cerebellar organization. We reveal topographically variegated scaling relationships between regional cerebellar volume and brain size in humans, which (1) are distinct from those observed in phylogeny, (2) invalidate a traditional neuroimaging method for brain volume correction, and (3) allow more valid and accurate resolution of which cerebellar subcomponents are sensitive to sex and sex chromosome complement. These findings advance understanding of cerebellar organization in health and sex chromosome aneuploidy. Copyright © 2017 the authors 0270-6474/17/375222-11$15.00/0.

Chapter 9: Implications of Air Pollutant Emissions from Producing Agricultural and Forestry Feedstocks

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

Warner, Ethan; Zhang, Yi Min; Inman, Daniel J

The 2016 Billion-Ton Report (BT16), Volume 2: Environmental Sustainability Effects of Select Scenarios from Volume 1, jointly released by the U.S. Department of Energy's Bioenergy Technologies Office (BETO) and Oak Ridge National Laboratory (ORNL), is a pioneering effort to analyze a range of potential environmental effects associated with illustrative near-term and long-term biomass-production scenarios from the 2016 Billion-Ton Report, Volume 1. This chapter of the 2016 Billion-Ton Report, Volume 2, was authored by NREL researchers Ethan Warner, Yimin Zhang, Danny Inman, Annika Eberle, Alberta Carpenter, Garvin Heath, and Dylan Hettinger.

Estimation of past seepage volumes from calcite distribution in the Topopah Spring Tuff, Yucca Mountain, Nevada

USGS Publications Warehouse

Marshall, B.D.; Neymark, L.A.; Peterman, Z.E.

2003-01-01

Low-temperature calcite and opal record the past seepage of water into open fractures and lithophysal cavities in the unsaturated zone at Yucca Mountain, Nevada, site of a proposed high-level radioactive waste repository. Systematic measurements of calcite and opal coatings in the Exploratory Studies Facility (ESF) tunnel at the proposed repository horizon are used to estimate the volume of calcite at each site of calcite and/or opal deposition. By estimating the volume of water required to precipitate the measured volumes of calcite in the unsaturated zone, seepage rates of 0.005 to 5 liters/year (l/year) are calculated at the median and 95th percentile of the measured volumes, respectively. These seepage rates are at the low end of the range of seepage rates from recent performance assessment (PA) calculations, confirming the conservative nature of the performance assessment. However, the distribution of the calcite and opal coatings indicate that a much larger fraction of the potential waste packages would be contacted by this seepage than is calculated in the performance assessment.

Reduction of variance in spectral estimates for correction of ultrasonic aberration.

PubMed

Astheimer, Jeffrey P; Pilkington, Wayne C; Waag, Robert C

2006-01-01

A variance reduction factor is defined to describe the rate of convergence and accuracy of spectra estimated from overlapping ultrasonic scattering volumes when the scattering is from a spatially uncorrelated medium. Assuming that the individual volumes are localized by a spherically symmetric Gaussian window and that centers of the volumes are located on orbits of an icosahedral rotation group, the factor is minimized by adjusting the weight and radius of each orbit. Conditions necessary for the application of the variance reduction method, particularly for statistical estimation of aberration, are examined. The smallest possible value of the factor is found by allowing an unlimited number of centers constrained only to be within a ball rather than on icosahedral orbits. Computations using orbits formed by icosahedral vertices, face centers, and edge midpoints with a constraint radius limited to a small multiple of the Gaussian width show that a significant reduction of variance can be achieved from a small number of centers in the confined volume and that this reduction is nearly the maximum obtainable from an unlimited number of centers in the same volume.

The Danger-to-Self-or-Others Exception to Confidentiality. ACA Legal Series, Volume 8.

ERIC Educational Resources Information Center

Ahia, C. Emmanuel; Martin, Dan

A counselor's obligation to safeguard information shared in counseling has clinical, ethical, and legal implications. This volume focuses on the duty-to-warn exception in client confidentiality. It provides general ethical and legal guidelines and, where possible, specific information to help the practitioner make good choices. It is intended for…

Transforming Education: Global Perspectives, Experiences and Implications. Educational Psychology: Critical Pedagogical Perspectives. Volume 24

ERIC Educational Resources Information Center

DeVillar, Robert A., Ed.; Jiang, Binbin, Ed.; Cummins, Jim, Ed.

2013-01-01

This research-based volume presents a substantive, panoramic view of ways in which Australia and countries in Africa, Asia, Europe, and North and South America engage in educational programs and practices to transform the learning processes and outcomes of their students. It reveals and analyzes national and global trajectories in key areas of…

SU-F-T-40: Can CBCT Images Be Used for Volume Studies of Prostate Seed Implants for Boost Treatment?

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

Xu, H; Lee, S; Diwanji, T

Purpose: In our clinic, the planning CT is used for definitive and boost low-dose-rate (LDR) brachytherapy treatments to determine the ultrasound volume in the operating room (OR) at the time of the implant. While the CT overestimation of OR volume is known, a larger estimation discrepancy has been observed for boost treatments. A possible reason is the prostate size reduction during EBRT for boost patients. Since cone-beam CT (CBCT) is often used as routine imaging guidance of EBRT, this prostate volume change may be captured. This study investigates if CBCT taken during EBRT includes the volume change information and thereforemore » beats CT in estimating the prostate OR volumes. Methods: 9 prostate patients treated with EBRT (45Gy in 1.8Gy per fractions to the whole pelvis) and I-125 seed implants (108Gy) were involved in this study. During EBRT, CBCT image guidance was performed on a weekly basis. For each patient, the prostate volumes on the first and the last available CBCT images were manually contoured by a physician. These volumes were then compared to each other and with the contoured volumes from the planning CT and from the ultrasound images in the OR. Results: The first and the last CBCT images did not show significant prostate volume change. Their average +/− standard deviation of prostate volumes were 24.4cc+/−14.6cc and 29.9cc+/−16.1cc, respectively (T-test p=0.68). The ratio of the OR volume to the last CBCT (0.71+/−0.21) was not significantly different from the ratio of OR volumes to the planning CT (0.61+/−0.13) (p=0.25). Conclusion: In this study, CBCT does not show significant prostate volume changes during EBRT. CBCT and CT volumes are quite consistent and no improvement of volume estimation using CBCT is observed. The advantage of CBCT as a replacement of CT for volume study of boost LDR brachytherapy is limited.« less

Calculation of hydrocarbon-in-place in gas and gas-condensate reservoirs - Carbon dioxide sequestration

USGS Publications Warehouse

Verma, Mahendra K.

2012-01-01

The Energy Independence and Security Act of 2007 (Public Law 110-140) authorized the U.S. Geological Survey (USGS) to conduct a national assessment of geologic storage resources for carbon dioxide (CO2), requiring estimation of hydrocarbon-in-place volumes and formation volume factors for all the oil, gas, and gas-condensate reservoirs within the U.S. sedimentary basins. The procedures to calculate in-place volumes for oil and gas reservoirs have already been presented by Verma and Bird (2005) to help with the USGS assessment of the undiscovered resources in the National Petroleum Reserve, Alaska, but there is no straightforward procedure available for calculating in-place volumes for gas-condensate reservoirs for the carbon sequestration project. The objective of the present study is to propose a simple procedure for calculating the hydrocarbon-in-place volume of a condensate reservoir to help estimate the hydrocarbon pore volume for potential CO2 sequestration.

Tidal Volume Estimation Using the Blanket Fractal Dimension of the Tracheal Sounds Acquired by Smartphone

PubMed Central

Reljin, Natasa; Reyes, Bersain A.; Chon, Ki H.

2015-01-01

In this paper, we propose the use of blanket fractal dimension (BFD) to estimate the tidal volume from smartphone-acquired tracheal sounds. We collected tracheal sounds with a Samsung Galaxy S4 smartphone, from five (N = 5) healthy volunteers. Each volunteer performed the experiment six times; first to obtain linear and exponential fitting models, and then to fit new data onto the existing models. Thus, the total number of recordings was 30. The estimated volumes were compared to the true values, obtained with a Respitrace system, which was considered as a reference. Since Shannon entropy (SE) is frequently used as a feature in tracheal sound analyses, we estimated the tidal volume from the same sounds by using SE as well. The evaluation of the performed estimation, using BFD and SE methods, was quantified by the normalized root-mean-squared error (NRMSE). The results show that the BFD outperformed the SE (at least twice smaller NRMSE was obtained). The smallest NRMSE error of 15.877% ± 9.246% (mean ± standard deviation) was obtained with the BFD and exponential model. In addition, it was shown that the fitting curves calculated during the first day of experiments could be successfully used for at least the five following days. PMID:25923929

Tidal volume estimation using the blanket fractal dimension of the tracheal sounds acquired by smartphone.

PubMed

Reljin, Natasa; Reyes, Bersain A; Chon, Ki H

2015-04-27

In this paper, we propose the use of blanket fractal dimension (BFD) to estimate the tidal volume from smartphone-acquired tracheal sounds. We collected tracheal sounds with a Samsung Galaxy S4 smartphone, from five (N = 5) healthy volunteers. Each volunteer performed the experiment six times; first to obtain linear and exponential fitting models, and then to fit new data onto the existing models. Thus, the total number of recordings was 30. The estimated volumes were compared to the true values, obtained with a Respitrace system, which was considered as a reference. Since Shannon entropy (SE) is frequently used as a feature in tracheal sound analyses, we estimated the tidal volume from the same sounds by using SE as well. The evaluation of the performed estimation, using BFD and SE methods, was quantified by the normalized root-mean-squared error (NRMSE). The results show that the BFD outperformed the SE (at least twice smaller NRMSE was obtained). The smallest NRMSE error of 15.877% ± 9.246% (mean ± standard deviation) was obtained with the BFD and exponential model. In addition, it was shown that the fitting curves calculated during the first day of experiments could be successfully used for at least the five following days.

Preoperative estimation of the liver graft weight in adult right lobe living donor liver transplantation using maximal portal vein diameters.

PubMed

Wang, Frank; Pan, Kuang-Tse; Chu, Sung-Yu; Chan, Kun-Ming; Chou, Hong-Shiue; Wu, Ting-Jung; Lee, Wei-Chen

2011-04-01

An accurate preoperative estimate of the graft weight is vital to avoid small-for-size syndrome in the recipient and ensure donor safety after adult living donor liver transplantation (LDLT). Here we describe a simple method for estimating the graft volume (GV) that uses the maximal right portal vein diameter (RPVD) and the maximal left portal vein diameter (LPVD). Between June 2004 and December 2009, 175 consecutive donors undergoing right hepatectomy for LDLT were retrospectively reviewed. The GV was determined with 3 estimation methods: (1) the radiological graft volume (RGV) estimated by computed tomography (CT) volumetry; (2) the computed tomography-calculated graft volume (CGV-CT), which was obtained by the multiplication of the standard liver volume (SLV) by the RGV percentage with respect to the total liver volume derived from CT; and (3) the portal vein diameter ratio-calculated graft volume (CGV-PVDR), which was obtained by the multiplication of the SLV by the portal vein diameter ratio [PVDR; ie, PVDR = RPVD(2) /(RPVD(2) + LPVD(2) )]. These values were compared to the actual graft weight (AGW), which was measured intraoperatively. The mean AGW was 633.63 ± 107.51 g, whereas the mean RGV, CGV-CT, and CGV-PVDR values were 747.83 ± 138.59, 698.21 ± 94.81, and 685.20 ± 90.88 cm(3) , respectively. All 3 estimation methods tended to overestimate the AGW (P < 0.001). The actual graft-to-recipient body weight ratio (GRWR) was 1.00% ± 0.19%, and the GRWRs calculated on the basis of the RGV, CGV-CT, and CGV-PVDR values were 1.19% ± 0.25%, 1.11% ± 0.22%, and 1.09% ± 0.21%, respectively. Overall, the CGV-PVDR values better correlated with the AGW and GRWR values according to Lin's concordance correlation coefficient and the Landis and Kock benchmark. In conclusion, the PVDR method is a simple estimation method that accurately predicts GVs and GRWRs in adult LDLT. Copyright © 2011 American Association for the Study of Liver Diseases.

The hydraulic permeability of blood clots as a function of fibrin and platelet density.

PubMed

Wufsus, A R; Macera, N E; Neeves, K B

2013-04-16

Interstitial fluid flow within blood clots is a biophysical mechanism that regulates clot growth and dissolution. Assuming that a clot can be modeled as a porous medium, the physical property that dictates interstitial fluid flow is the hydraulic permeability. The objective of this study was to bound the possible values of the hydraulic permeability in clots formed in vivo and present relationships that can be used to estimate clot permeability as a function of composition. A series of clots with known densities of fibrin and platelets, the two major components of a clot, were formed under static conditions. The permeability was calculated by measuring the interstitial fluid velocity through the clots at a constant pressure gradient. Fibrin gels formed with a fiber volume fraction of 0.02-0.54 had permeabilities of 1.2 × 10(-1)-1.5 × 10(-4)μm(2). Platelet-rich clots with a platelet volume fraction of 0.01-0.61 and a fibrin volume fraction of 0.03 had permeabilities over a range of 1.1 × 10(-2)-1.5 × 10(-5)μm(2). The permeability of fibrin gels and of clots with platelet volume fraction of <0.2 were modeled as an array of disordered cylinders with uniform diameters. Clots with a platelet volume fraction of >0.2 were modeled as a Brinkman medium of coarse solids (platelets) embedded in a mesh of fine fibers (fibrin). Our data suggest that the permeability of clots formed in vivo can vary by up to five orders of magnitude, with pore sizes that range from 4 to 350 nm. These findings have important implications for the transport of coagulation zymogens/enzymes in the interstitial spaces during clot formation, as well as the design of fibrinolytic drug delivery strategies. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Quantification of a maximum injection volume of CO2 to avert geomechanical perturbations using a compositional fluid flow reservoir simulator

NASA Astrophysics Data System (ADS)

Jung, Hojung; Singh, Gurpreet; Espinoza, D. Nicolas; Wheeler, Mary F.

2018-02-01

Subsurface CO2 injection and storage alters formation pressure. Changes of pore pressure may result in fault reactivation and hydraulic fracturing if the pressure exceeds the corresponding thresholds. Most simulation models predict such thresholds utilizing relatively homogeneous reservoir rock models and do not account for CO2 dissolution in the brine phase to calculate pore pressure evolution. This study presents an estimation of reservoir capacity in terms of allowable injection volume and rate utilizing the Frio CO2 injection site in the coast of the Gulf of Mexico as a case study. The work includes laboratory core testing, well-logging data analyses, and reservoir numerical simulation. We built a fine-scale reservoir model of the Frio pilot test in our in-house reservoir simulator IPARS (Integrated Parallel Accurate Reservoir Simulator). We first performed history matching of the pressure transient data of the Frio pilot test, and then used this history-matched reservoir model to investigate the effect of the CO2 dissolution into brine and predict the implications of larger CO2 injection volumes. Our simulation results -including CO2 dissolution- exhibited 33% lower pressure build-up relative to the simulation excluding dissolution. Capillary heterogeneity helps spread the CO2 plume and facilitate early breakthrough. Formation expansivity helps alleviate pore pressure build-up. Simulation results suggest that the injection schedule adopted during the actual pilot test very likely did not affect the mechanical integrity of the storage complex. Fault reactivation requires injection volumes of at least about sixty times larger than the actual injected volume at the same injection rate. Hydraulic fracturing necessitates much larger injection rates than the ones used in the Frio pilot test. Tested rock samples exhibit ductile deformation at in-situ effective stresses. Hence, we do not expect an increase of fault permeability in the Frio sand even in the presence of fault reactivation.

The Hydraulic Permeability of Blood Clots as a Function of Fibrin and Platelet Density

PubMed Central

Wufsus, A.R.; Macera, N.E.; Neeves, K.B.

2013-01-01

Interstitial fluid flow within blood clots is a biophysical mechanism that regulates clot growth and dissolution. Assuming that a clot can be modeled as a porous medium, the physical property that dictates interstitial fluid flow is the hydraulic permeability. The objective of this study was to bound the possible values of the hydraulic permeability in clots formed in vivo and present relationships that can be used to estimate clot permeability as a function of composition. A series of clots with known densities of fibrin and platelets, the two major components of a clot, were formed under static conditions. The permeability was calculated by measuring the interstitial fluid velocity through the clots at a constant pressure gradient. Fibrin gels formed with a fiber volume fraction of 0.02–0.54 had permeabilities of 1.2 × 10−1–1.5 × 10−4μm2. Platelet-rich clots with a platelet volume fraction of 0.01–0.61 and a fibrin volume fraction of 0.03 had permeabilities over a range of 1.1 × 10−2–1.5 × 10−5μm2. The permeability of fibrin gels and of clots with platelet volume fraction of <0.2 were modeled as an array of disordered cylinders with uniform diameters. Clots with a platelet volume fraction of >0.2 were modeled as a Brinkman medium of coarse solids (platelets) embedded in a mesh of fine fibers (fibrin). Our data suggest that the permeability of clots formed in vivo can vary by up to five orders of magnitude, with pore sizes that range from 4 to 350 nm. These findings have important implications for the transport of coagulation zymogens/enzymes in the interstitial spaces during clot formation, as well as the design of fibrinolytic drug delivery strategies. PMID:23601328

Critical Issues in Special Education: Implications for Personnel Preparation. Monograph.

ERIC Educational Resources Information Center

Bullock, Lyndal M., Ed.; Simpson, Richard L., Ed.

This document is the product of a forum that attempted to identify trends in education that are affecting and will continue to affect children with disabilities from birth to age 21, and the ensuing implications for the training of personnel. The edited transcripts of two introductory presentations begin with volume--"Charting the Course for…

Translating Theory into Practice: Implications of Japanese Management Theory for Student Personnel Administrators. NASPA Monograph Series Volume 3. First Edition.

ERIC Educational Resources Information Center

Deegan, William L.; And Others

Japanese management theory was studied to identify specific models for consideration by student personnel administrators. The report is organized into three sections: major components of Japanese management theory, potential implications for student personnel administration, and three models, based on components of Japanese management theory, for…

The Red Light in the Ivory Tower: Contexts and Implications of Entrepreneurial Education. Counterpoints: Studies in the Postmodern Theory of Education. Volume 401

ERIC Educational Resources Information Center

Breault, Donna Adair; Callejo Perez, David M.

2012-01-01

"The Red Light in the Ivory Tower: Contexts and Implications of Entrepreneurial Education" critically analyzes the operational behaviors of prestigious and prestige-seeking universities, particularly within the context of budget shortfalls and increasing competition. The book challenges entrepreneurial activities within universities by exploring…

Draft/Registration/National Service. Current Issues in Catholic Higher Education. Volume 1, Number 1.

ERIC Educational Resources Information Center

Gallin, Alice, Ed.

A collection of nine brief statements by prominent Catholics and other religious policymakers on the moral implications of compulsory military and other national service is presented. Each of the respondents answers the following question: "In your judgment, what are the moral and ethical implications of a public policy, in time of peace, of…

Assessment of single-shell tank residual-liquid issues at Hanford Site, Washington

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

Murthy, K.S.; Stout, L.A.; Napier, B.A.

1983-06-01

This report provides an assessment of the overall effectiveness and implications of jet pumping the interstitial liquids (IL) from single-shell tanks at Hanford. The jet-pumping program, currently in progress at Hanford, involves the planned removal of IL contained in 89 of the 149 single-shell tanks and its transfer to double-shell tanks after volume reduction by evaporation. The purpose of this report is to estimate the public and worker doses associated with (1) terminating pumping immediately, (2) pumping to a 100,000-gal limit per tank, (3) pumping to a 50,000-gal limit per tank, and (4) pumping to the maximum practical liquid removalmore » level of 30,000 gal. Assessment of the cost-effectiveness of these various levels of pumping in minimizing any undue health and safety risks to the public or worker is also presented.« less

Mass transfer dynamics of ammonia in high rate biomethanation of poultry litter leachate.

PubMed

Gangagni Rao, A; Gandu, Bharath; Swamy, Y V

2012-04-01

In the present study possibility of coupling biofilter to arrest ammonia (NH(3)) emission to the atmosphere from the integrated UASB and stripper (UASB+ST) system treating poultry litter leachate was studied. UASB+ST with biofilter (UASB+ST+BF) exhibited removal efficiency (RE) of NH(3) in the range of 98-99% (below 28 ppmV (parts per million by volume)) with low cost agricultural residue as a bedding material. Mass transfer dynamics of TAN in the system revealed that TAN loss to atmosphere was below 1% in UASB+ST+BF where as it was in the range of 70-90% in UASB+ST. Cost estimates revealed that financial implications due to the addition of biofilter were below 10% of total capital cost. TAN retained in the bedding material of biofilter could also be utilized as soil conditioner upon saturation. Copyright © 2012 Elsevier Ltd. All rights reserved.

An Avoidance Model for Short-Range Order Induced by Soft Repulsions in Systems of Rigid Rods

NASA Astrophysics Data System (ADS)

Han, Jining; Herzfeld, Judith

1996-03-01

The effects of soft repulsions on hard particle systems are calculated using an avoidance model which improves upon the simple mean field approximation. Avoidance reduces, but does not eliminate, the energy due to soft repulsions. On the other hand, it also reduces the configurational entropy. Under suitable conditions, this simple trade-off yields a free energy that is lower than the mean field value. In these cases, the variationally determined avoidance gives an estimate for the short-range positional order induced by soft repulsions. The results indicate little short-range order for isotropically oriented rods. However, for parallel rods, short-range order increases to significant levels as the particle axial ratio increases. The implications for long- range positional ordering are also discussed. In particular, avoidance may explain the smectic ordering of tobacco mosaic virus at volume fractions lower than those necessary for smectic ordering of hard particles.

Global biomass burning - Atmospheric, climatic, and biospheric implications

NASA Technical Reports Server (NTRS)

Levine, Joel S. (Editor)

1991-01-01

The present volume discusses the biomass burning (BMB) studies of the International Global Atmospheric Chemistry project, GEO satellite estimation of Amazonian BMB, remote sensing of BMB in West Africa with NOAA-AVHRR, an orbital view of the great Chinese fire of 1987, BMB's role in tropical rainforest reduction, CO and O3 measurements of BMB in the Amazon, effects of vegetation burning on the atmospheric chemistry of the Venezuelan savanna, an assessment of annually-burned biomass in Africa, and light hydrocarbon emissions from African savanna burnings. Also discussed are BMB in India, trace gas and particulate emissions from BMB in temperate ecosystems, ammonia and nitric acid emissions from wetlands and boreal forest fires, combustion emissions and satellite imagery of BMB, BMB in the perspective of the global carbon cycle, modeling trace-gas emissions from BMB, NO(x) emissions from BMB, and cloud-condensation nuclei from BMB.

A chiral diamine: practical implications of a three-stereoisomer cocrystallization.

PubMed

Dolinar, Brian S; Samedov, Kerim; Maloney, Andrew G P; West, Robert; Khrustalev, Victor N; Guzei, Ilia A

2018-01-01

A brief comparison of seven straightforward methods for molecular crystal-volume estimation revealed that their precisions are comparable. A chiral diamine, N 2 ,N 3 -bis[2,6-bis(propan-2-yl)phenyl]butane-2,3-diamine, C 28 H 44 N 2 , has been used to illustrate the application of the methods. Three stereoisomers of the diamine cocrystallize in the centrosymmetric space group P2 1 /c with Z' = 1.5. The molecules occupying general positions are RR and SS, whereas that residing on an inversion center is meso. This is one of only ten examples of three stereoisomers with two asymmetric atoms cocrystallizing together reported to the Cambridge Structural Database (CSD). The conformations of the SS/RR and meso molecules differ considerably and lead to statistically significantly different C(asymmetric)-C(asymmetric) bond lengths in the diastereomers. An advanced Python script-based CSD searching technique for chiral compounds is presented.

The sensitivity of derived estimates to the measurment quality objectives for independent variables

Treesearch

Francis A. Roesch

2002-01-01

The effect of varying the allowed measurement error for individual tree variables upon county estimates of gross cubic-foot volume was examined. Measurement Quality Ob~ectives (MQOs) for three forest tree variables (biological identity, diameter, and height) used in individual tree gross cubic-foot volume equations were varied from the current USDA Forest Service...

The Sensitivity of Derived Estimates to the Measurement Quality Objectives for Independent Variables

Treesearch

Francis A. Roesch

2005-01-01

The effect of varying the allowed measurement error for individual tree variables upon county estimates of gross cubic-foot volume was examined. Measurement Quality Objectives (MQOs) for three forest tree variables (biological identity, diameter, and height) used in individual tree gross cubic-foot volume equations were varied from the current USDA Forest Service...

A Growth and Yield Model for Thinned Stands of Yellow-Poplar

Treesearch

Bruce R. Knoebel; Harold E. Burkhart; Donald E. Beck

1986-01-01

Simultaneous growth and yield equations were developed for predicting basal area growth and cubic-foot volume growth and yield in thinned stands of yellow-poplar. A joint loss function involving both volume and basal area was used to estimate the coefficients in the system of equations. The estimates obtained were analytically compatible, invariant for projection...

Photo stratification improves northwest timber volume estimates.

Treesearch

Colin D. MacLean

1972-01-01

Data from extensive timber inventories of 12 counties in western and central Washington were analyzed to test the relative efficiency of double sampling for stratification as a means of estimating total volume. Photo and field plots, when combined in a stratified sampling design, proved about twice as efficient as simple field sampling. Although some gains were made by...

North Dakota's forest resources in 2002.

Treesearch

David Haugen; Gary Brand; Travis Rymal; Michael Kangas

2004-01-01

Results of the combined 2001 and 2002 annual forest inventories of North Dakota show over 824 thousand acres of forest land. There are an estimated 744 million cubic feet of all live tree volume, or approximately 902 cubic feet per acre of forest land. Timberland totals 696 million acres with an estimated 409 million cubic feet of growing-stock volume, or...

Illinois' forest resources, 2005

Treesearch

Susan J. Crocker; Gary J. Brand; Dick C. Little

2007-01-01

Results of the completed 2005 Illinois annual inventory show an estimated 4.5 million acres of forest land that supports 7.6 billion cubic feet (ft3) of total net live-tree volume. Since 1948, timberland area has steadily increased and now represents 96 percent of total forest land. Growing-stock volume on timberland has risen to an estimated 6.8...

Robust Means and Covariance Matrices by the Minimum Volume Ellipsoid (MVE).

ERIC Educational Resources Information Center

Blankmeyer, Eric

P. Rousseeuw and A. Leroy (1987) proposed a very robust alternative to classical estimates of mean vectors and covariance matrices, the Minimum Volume Ellipsoid (MVE). This paper describes the MVE technique and presents a BASIC program to implement it. The MVE is a "high breakdown" estimator, one that can cope with samples in which as…

The forest-land owners of New Hampshire and Vermont

Treesearch

Neal P. Kingsley; Thomas W. Birch

1977-01-01

The recently completed forest surveys of New Hampshire and Vermont provided estimates of forest area and timber volume by broad owner categories (Kingsley 1976 and 1977). However, these reports did not provide estimates of the volume of timber or the acreage of commercial forest land that is currently available for harvesting. Nor did they provide descriptions of...

Temporal validation for landsat-based volume estimation model

Treesearch

Renaldo J. Arroyo; Emily B. Schultz; Thomas G. Matney; David L. Evans; Zhaofei Fan

2015-01-01

Satellite imagery can potentially reduce the costs and time associated with ground-based forest inventories; however, for satellite imagery to provide reliable forest inventory data, it must produce consistent results from one time period to the next. The objective of this study was to temporally validate a Landsat-based volume estimation model in a four county study...

Simple Estimation of the Endolymphatic Volume Ratio after Intravenous Administration of a Single-dose of Gadolinium Contrast.

PubMed

Naganawa, Shinji; Kanou, Mai; Ohashi, Toshio; Kuno, Kayao; Sone, Michihiko

2016-10-11

To evaluate the feasibility of a simple estimation for the endolymphatic volume ratio (endolymph volume/total lymph volume = %EL volume ) from an area ratio obtained from only one slice (%EL 1slice ) or from three slices (%EL 3slices ). The %EL volume, calculated from a time-consuming measurement on all magnetic resonance (MR) slices, was compared to the %EL 1slice and the %EL 3slices . In 40 ears of 20 patients with a clinical suspicion of endolymphatic hydrops, MR imaging was performed 4 hours after intravenous administration of a single dose of gadolinium-based contrast material (IV-SD-GBCM). Using previously reported HYDROPS2-Mi2 MR imaging, the %EL volume values in the cochlea and the vestibule were measured separately by two observers. The correlations between the %EL 1slice or the %EL 3slices and the %EL volume values were evaluated. A strong linear correlation was observed between the %EL volume and the %EL 3slices or the %EL 1slice in the cochlea. The Pearson correlation coefficient (r) was 0.968 (3 slices) and 0.965 (1 slice) for observer A, and 0.968 (3 slices) and 0.964 (1 slice) for observer B (P < 0.001, for all). A strong linear correlation was also observed between the %EL volume and the %EL 3slices or the %EL 1slice in the vestibule. The Pearson correlation coefficient (r) was 0.980 (3 slices) and 0.953 (1 slice) for observer A, and 0.979 (3 slices) and 0.952 (1 slice) for observer B (P < 0.001, for all). The high intra-class correlation coefficients (0.991-0.997) between the endolymph volume ratios by two observers were observed in both the cochlea and the vestibule for values of the %EL volume , the %EL 3slices and the %EL 1slice . The %EL volume might be easily estimated from the %EL 3slices or the %EL 1slice .

Interior volume of (1 + D)-dimensional Schwarzschild black hole

NASA Astrophysics Data System (ADS)

Bhaumik, Nilanjandev; Majhi, Bibhas Ranjan

2018-01-01

We calculate the maximum interior volume, enclosed by the event horizon, of a (1 + D)-dimensional Schwarzschild black hole. Taking into account the mass change due to Hawking radiation, we show that the volume increases towards the end of the evaporation. This fact is not new as it has been observed earlier for four-dimensional case. The interesting point we observe is that this increase rate decreases towards the higher value of space dimensions D; i.e. it is a decelerated expansion of volume with the increase of spatial dimensions. This implies that for a sufficiently large D, the maximum interior volume does not change. The possible implications of these results are also discussed.

Left ventricular volume estimation in cardiac three-dimensional ultrasound: a semiautomatic border detection approach.

PubMed

van Stralen, Marijn; Bosch, Johan G; Voormolen, Marco M; van Burken, Gerard; Krenning, Boudewijn J; van Geuns, Robert-Jan M; Lancée, Charles T; de Jong, Nico; Reiber, Johan H C

2005-10-01

We propose a semiautomatic endocardial border detection method for three-dimensional (3D) time series of cardiac ultrasound (US) data based on pattern matching and dynamic programming, operating on two-dimensional (2D) slices of the 3D plus time data, for the estimation of full cycle left ventricular volume, with minimal user interaction. The presented method is generally applicable to 3D US data and evaluated on data acquired with the Fast Rotating Ultrasound (FRU-) Transducer, developed by Erasmus Medical Center (Rotterdam, the Netherlands), a conventional phased-array transducer, rotating at very high speed around its image axis. The detection is based on endocardial edge pattern matching using dynamic programming, which is constrained by a 3D plus time shape model. It is applied to an automatically selected subset of 2D images of the original data set, for typically 10 equidistant rotation angles and 16 cardiac phases (160 images). Initialization requires the drawing of four contours per patient manually. We evaluated this method on 14 patients against MRI end-diastole and end-systole volumes. Initialization requires the drawing of four contours per patient manually. We evaluated this method on 14 patients against MRI end-diastolic (ED) and end-systolic (ES) volumes. The semiautomatic border detection approach shows good correlations with MRI ED/ES volumes (r = 0.938) and low interobserver variability (y = 1.005x - 16.7, r = 0.943) over full-cycle volume estimations. It shows a high consistency in tracking the user-defined initial borders over space and time. We show that the ease of the acquisition using the FRU-transducer and the semiautomatic endocardial border detection method together can provide a way to quickly estimate the left ventricular volume over the full cardiac cycle using little user interaction.

4D-CT motion estimation using deformable image registration and 5D respiratory motion modeling.

PubMed

Yang, Deshan; Lu, Wei; Low, Daniel A; Deasy, Joseph O; Hope, Andrew J; El Naqa, Issam

2008-10-01

Four-dimensional computed tomography (4D-CT) imaging technology has been developed for radiation therapy to provide tumor and organ images at the different breathing phases. In this work, a procedure is proposed for estimating and modeling the respiratory motion field from acquired 4D-CT imaging data and predicting tissue motion at the different breathing phases. The 4D-CT image data consist of series of multislice CT volume segments acquired in ciné mode. A modified optical flow deformable image registration algorithm is used to compute the image motion from the CT segments to a common full volume 3D-CT reference. This reference volume is reconstructed using the acquired 4D-CT data at the end-of-exhalation phase. The segments are optimally aligned to the reference volume according to a proposed a priori alignment procedure. The registration is applied using a multigrid approach and a feature-preserving image downsampling maxfilter to achieve better computational speed and higher registration accuracy. The registration accuracy is about 1.1 +/- 0.8 mm for the lung region according to our verification using manually selected landmarks and artificially deformed CT volumes. The estimated motion fields are fitted to two 5D (spatial 3D+tidal volume+airflow rate) motion models: forward model and inverse model. The forward model predicts tissue movements and the inverse model predicts CT density changes as a function of tidal volume and airflow rate. A leave-one-out procedure is used to validate these motion models. The estimated modeling prediction errors are about 0.3 mm for the forward model and 0.4 mm for the inverse model.

Evaluation of burst-mode LDA spectra with implications

NASA Astrophysics Data System (ADS)

Velte, Clara; George, William

2009-11-01

Burst-mode LDA spectra, as described in [1], are compared to spectra obtained from corresponding HWA measurements using the FFT in a round jet and cylinder wake experiment. The phrase ``burst-mode LDA'' refers to an LDA which operates with at most one particle present in the measuring volume at a time. Due to the random sampling and velocity bias of the LDA signal, the Direct Fourier Transform with accompanying weighting by the measured residence times was applied to obtain a correct interpretation of the spectral estimate. Further, the self-noise was removed as described in [2]. In addition, resulting spectra from common interpolation and uniform resampling techniques are compared to the above mentioned estimates. The burst-mode LDA spectra are seen to concur well with the HWA spectra up to the emergence of the noise floor, caused mainly by the intermittency of the LDA signal. The interpolated and resampled counterparts yield unphysical spectra, which are buried in frequency dependent noise and step noise, except at very high LDA data rates where they perform well up to a limited frequency.[4pt] [1] Buchhave, P. PhD Thesis, SUNY/Buffalo, 1979.[0pt] [2] Velte, C.M. PhD Thesis, DTU/Copenhagen, 2009.

The effect of urinary cadmium on cardiovascular fitness as measured by VO{sub 2} max in white, black and Mexican Americans

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

Egwuogu, Heartley; Shendell, Derek G.; Department of Environmental and Occupational Health, University of Medicine and Dentistry of New Jersey

Objectives: We explored potential effects of cadmium exposure on cardiovascular fitness measures, including gender and racial/ethnic differences. Methods: Data were from the 1999 to 2000 National Health and Nutrition Examination Survey (NHANES); 1963 participating subjects were included in our analysis. Volume of oxygen consumed at sub-maximum activity (VO{sub 2} max) were recorded in a series of graded exercises; the goal was to elicit 75% of predetermined age-specific heart rates. Cadmium from urine samples was measured in the laboratory using standard methods. Multivariate linear regression analyses were performed to determine potential relationships. Results: Increased urinary cadmium concentrations were generally associated withmore » decreased estimated VO{sub 2} max values. Gender and racial/ethnic differences were also observed. Specifically, associations were statistically significant for white males and Mexican American females. Conclusion: Inverse associations between urinary cadmium concentrations and estimated VO{sub 2} max values were observed, including racial and gender differences. The implications of such gender and racial/ethnic differences on long-term cardiovascular health and health disparities of present public health concern warrant further investigation.« less

Thermal infrared spectral analysis of compacted fine-grained mineral mixtures: implications for spectral interpretation of lithified sedimentary materials on Mars

NASA Astrophysics Data System (ADS)

Pan, C.; Rogers, D.

2012-12-01

Characterizing the thermal infrared (TIR) spectral mixing behavior of compacted fine-grained mineral assemblages is necessary for facilitating quantitative mineralogy of sedimentary surfaces from spectral measurements. Previous researchers have demonstrated that TIR spectra from igneous and metamorphic rocks as well as coarse-grained (>63 micron) sand mixtures combine in proportion to their volume abundance. However, the spectral mixing behavior of compacted, fine-grained mineral mixtures that would be characteristic of sedimentary depositional environments has received little attention. Here we characterize the spectral properties of pressed pellet samples of <10 micron mineral mixtures to 1) assess linearity of spectral combinations, 2) determine whether there are consistent over- or under-estimations of different types of minerals in spectral models and 3) determine if model accuracy can be improved by including both fine- and coarse-grained end-members. Major primary and secondary minerals found on the Martian surface including feldspar, pyroxene, smectite, sulfate and carbonate were crushed with an agate mortar and pestle and centrifuged to obtain less than 10 micron size. Pure phases and mixtures of two, three and four components were made in varying proportions by volume. All of the samples were pressed into pellets at 15000PSI to minimize volume scattering. Thermal infrared spectra of pellets were measured in the Vibrational Spectroscopy Laboratory at Stony Brook University with a Thermo Fisher Nicolet 6700 Fourier transform infrared Michelson interferometer from ~225 to 2000 cm-1. Our preliminary results indicate that some pelletized samples have contributions from volume scattering, which leads to non-linear spectral combinations. It is not clear if the transparency features (which arise from multiple surface reflections of incident photons) are due to minor clinging fines on an otherwise specular pellet surface or to partially transmitted energy through optically thin grains in the compacted mixture. Inclusion of loose powder (<10 μm) sample spectra improves mineral abundance estimates for some mixtures. In general, mineral abundances are predicted to within +/- 10% (absolute) for approximately 60% of our samples; thus far, there are no clear trends in which cases produce better model results. With the exception of pyroxene/feldspar ratios being consistently overestimated, there are no consistent trends in over- or under-estimation of minerals. The results described here are based on the unsubstantiated assumption that areal abundance on the pellet surface is equal to the volume abundance. Thus future work will include micro-imaging of our samples to constrain areal abundance. We will also prepareclay mixtures using a wetting/drying sequence rather than pressure, and expand our set of samples to include additional mixture combinations to further characterize the spectral behavior of compacted mixtures. This work will be directly applicable to analysis of TES and Mini-TES data of lithified sedimentary deposits.

U.S. Geological Survey assessment of reserve growth outside of the United States

USGS Publications Warehouse

Klett, Timothy R.; Cook, Troy A.; Charpentier, Ronald R.; Tennyson, Marilyn E.; Le, Phuong A.

2015-12-21

The U.S. Geological Survey estimated volumes of technically recoverable, conventional petroleum resources resulting from reserve growth for discovered fields outside the United States that have reported in-place oil and gas volumes of 500 million barrels of oil equivalent or greater. The mean volumes of reserve growth were estimated at 665 billion barrels of crude oil; 1,429 trillion cubic feet of natural gas; and 16 billion barrels of natural gas liquids. These volumes constitute a significant portion of the world’s oil and gas resources and represent the potential future growth of current global reserves over time based on better assessment methodology, new technologies, and greater understanding of reservoirs.