Volume to Surface Area Ratios of Foraminifera over the Phanerozoic

NASA Astrophysics Data System (ADS)

Cheung, K.; Gomez, D.; Guo, D.; Jost, A.; Payne, J.

2010-12-01

Although there have been numerous studies regarding the issue of the volume to surface area ratio, no study has been extensive enough to include over 35000 species of foraminifera. The Stanford Paleobiology lab undertook the enormous task of extracting from the Catalogue of Foraminifera, by Ellis and Messina, all relevant data of the foraminifera, such as the three dimensions of the organism, the magnification, and the time period in which the organism existed. For the purpose of calculating the volume and surface area, the foraminifera were generalized as ellipsoids. It is known that the surface area of foraminifera represents where the exchange between the interior body and exterior environment of the foraminifera occurs. The volume of the foraminifera indicates the physical needs of the foraminifera. With more volume in foraminifera, more body functions are occurring and more exterior resources are needed to sustain those bodily functions. Thus with a larger volume to surface area ratio, foraminifera are disadvantaged because they must use more effort in order to acquire adequate resources to fulfill their biological needs. So, the hypothesis is that when there is an increase in oxygen (a vital exterior resource of the foraminifera), the average volume to surface area ratio would be greater because the abundance of oxygen allows foraminifera to work with greater ease in maintaining an exterior resource that they cannot survive without. To prove or refute this assertion, graphs were generated in this study; the graphs indeed suggested that there is a correlation between the volume to surface area ratios and oxygen levels, illustrating that it is plausible that oxygen is a limiting factor of the volume to surface area ratio in foraminifera.

Stereological estimation of cell wall density of DR12 tomato mutant using three-dimensional confocal imaging

PubMed Central

Legland, David; Guillon, Fabienne; Kiêu, Kiên; Bouchet, Brigitte; Devaux, Marie-Françoise

2010-01-01

Background and Aims The cellular structure of fleshy fruits is of interest to study fruit shape, size, mechanical behaviour or sensory texture. The cellular structure is usually not observed in the whole fruit but, instead, in a sample of limited size and volume. It is therefore difficult to extend measurements to the whole fruit and/or to a specific genotype, or to describe the cellular structure heterogeneity within the fruit. Methods An integrated method is presented to describe the cellular structure of the whole fruit from partial three-dimensional (3D) observations, involving the following steps: (1) fruit sampling, (2) 3D image acquisition and processing and (3) measurement and estimation of relevant 3D morphological parameters. This method was applied to characterize DR12 mutant and wild-type tomatoes (Solanum lycopersicum). Key Results The cellular structure was described using the total volume of the pericarp, the surface area of the cell walls and the ratio of cell-wall surface area to pericarp volume, referred to as the cell-wall surface density. The heterogeneity of cellular structure within the fruit was investigated by estimating variations in the cell-wall surface density with distance to the epidermis. Conclusions The DR12 mutant presents a greater pericarp volume and an increase of cell-wall surface density under the epidermis. PMID:19952012

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.

Nanomaterial containing wall paints can increase radon concentration in houses located in radon prone areas.

PubMed

Haghani, M; Mortazavi, S M J; Faghihi, R; Mehdizadeh, S; Moradgholi, J; Darvish, L; Fathi-Pour, E; Ansari, L; Ghanbar-Pour, M R

2013-09-01

Nowadays, extensive technological advancements have made it possible to use nanopaints which show exciting properties. In IR Iran excessive radon levels (up to 3700 Bq m-3) have been reported in homes located in radon prone areas. Over the past decades, concerns have been raised about the risk posed by residential radon exposure. This study aims at investigating the effect of using nanomaterial containing wall paints on radon concentration in homes. Two wooden model houses were used in this study. Soil samples from Ramsar high background radiation areas were used for simulating the situation of a typical house in radon-prone areas. Conventional water-soluble wall paint was used for painting the walls of the 1st house model; while the 2nd house model was painted with the same wall paint with montmorillonitenanoclay. Three days after sealing the house models, radon level was measured by using a portable radon survey meter. The mean radon level inside the 1st house model (conventional paint) was 515.3 ± 17.8 Bq/m(3) while the mean radon concentration in the 2nd house model (nano-painted house model) was 570.8 ± 18.5 Bq/m(3). The difference between these means was statistically significant (P<0.001). To the best of our knowledge, this study is the first investigation on the effect of nano-material containing wall paints on indoor radon concentrations.  It can be concluded that nano-material-containing wall paints should not be used in houses with wooden walls located in radon prone areas. Although the mechanism of this effect is not clearly known, decreased porosity in nano-paints might be a key factor in increasing the radon concentration in homes.

Nanomaterial Containing Wall Paints Can Increase Radon Concentration in Houses Located in Radon Prone Areas

PubMed Central

Haghani, M.; Mortazavi, S. M. J.; Faghihi, R.; Mehdizadeh, S.; Moradgholi, J.; Darvish, L.; Fathi-Pour, E.; Ansari, L.; Ghanbar-pour, M. R.

2013-01-01

Background: Nowadays, extensive technological advancements have made it possible to use nanopaints which show exciting properties. In IR Iran excessive radon levels (up to 3700 Bq m–3) have been reported in homes located in radon prone areas. Over the past decades, concerns have been raised about the risk posed by residential radon exposure. Objective: This study aims at investigating the effect of using nanomaterial containing wall paints on radon concentration in homes. Methods: Two wooden model houses were used in this study. Soil samples from Ramsar high background radiation areas were used for simulating the situation of a typical house in radon-prone areas. Conventional water-soluble wall paint was used for painting the walls of the 1st house model; while the 2nd house model was painted with the same wall paint with montmorillonitenanoclay. Results: Three days after sealing the house models, radon level was measured by using a portable radon survey meter. The mean radon level inside the 1st house model (conventional paint) was 515.3 ± 17.8 Bq/m3 while the mean radon concentration in the 2nd house model (nano-painted house model) was 570.8 ± 18.5 Bq/m3. The difference between these means was statistically significant (P<0.001). Conclusion: To the best of our knowledge, this study is the first investigation on the effect of nano-material containing wall paints on indoor radon concentrations.  It can be concluded that nano-material-containing wall paints should not be used in houses with wooden walls located in radon prone areas. Although the mechanism of this effect is not clearly known, decreased porosity in nano-paints might be a key factor in increasing the radon concentration in homes. PMID:25505754

West wall, display area (room 101), view 4 of 4: ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

West wall, display area (room 101), view 4 of 4: northwest corner, with D.M. logistics office below (room 137), and D.O./D.D.O. offices above. Lower stairs lead to entry shown in view 13 - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

Surface area-volume ratios in insects.

PubMed

Kühsel, Sara; Brückner, Adrian; Schmelzle, Sebastian; Heethoff, Michael; Blüthgen, Nico

2017-10-01

Body mass, volume and surface area are important for many aspects of the physiology and performance of species. Whereas body mass scaling received a lot of attention in the literature, surface areas of animals have not been measured explicitly in this context. We quantified surface area-volume (SA/V) ratios for the first time using 3D surface models based on a structured light scanning method for 126 species of pollinating insects from 4 orders (Diptera, Hymenoptera, Lepidoptera, and Coleoptera). Water loss of 67 species was measured gravimetrically at very dry conditions for 2 h at 15 and 30 °C to demonstrate the applicability of the new 3D surface measurements and relevance for predicting the performance of insects. Quantified SA/V ratios significantly explained the variation in water loss across species, both directly or after accounting for isometric scaling (residuals of the SA/V ∼ mass 2/3 relationship). Small insects with a proportionally larger surface area had the highest water loss rates. Surface scans of insects to quantify allometric SA/V ratios thus provide a promising method to predict physiological responses, improving the potential of body mass isometry alone that assume geometric similarity. © 2016 Institute of Zoology, Chinese Academy of Sciences.

A modified ATI technique for nowcasting convective rain volumes over areas. [area-time integrals

NASA Technical Reports Server (NTRS)

Makarau, Amos; Johnson, L. Ronald; Doneaud, Andre A.

1988-01-01

This paper explores the applicability of the area-time-integral (ATI) technique for the estimation of the growth portion only of a convective storm (while the rain volume is computed using the entire life history of the event) and for nowcasting the total rain volume of a convective system at the stage of its maximum development. For these purposes, the ATIs were computed from the digital radar data (for 1981-1982) from the North Dakota Cloud Modification Project, using the maximum echo area (ATIA) no less than 25 dBz, the maximum reflectivity, and the maximum echo height as the end of the growth portion of the convective event. Linear regression analysis demonstrated that correlations between total rain volume or the maximum rain volume versus ATIA were the strongest. The uncertainties obtained were comparable to the uncertainties which typically occur in rain volume estimates obtained from radar data employing Z-R conversion followed by space and time integration. This demonstrates that the total rain volume of a storm can be nowcasted at its maximum stage of development.

Dosimetric impact in the dose-volume histograms of rectal and vesical wall contouring in prostate cancer IMRT treatments.

PubMed

Gómez, Laura; Andrés, Carlos; Ruiz, Antonio

2017-01-01

The main purpose of this study was to evaluate the differences in dose-volume histograms of IMRT treatments for prostate cancer based on the delineation of the main organs at risk (rectum and bladder) as solid organs or by contouring their wall. Rectum and bladder have typically been delineated as solid organs, including the waste material, which, in practice, can lead to an erroneous assessment of the risk of adverse effects. A retrospective study was made on 25 patients treated with IMRT radiotherapy for prostate adenocarcinoma. 76.32 Gy in 36 fractions was prescribed to the prostate and seminal vesicles. In addition to the delineation of the rectum and bladder as solid organs (including their content), the rectal and bladder wall were also delineated and the resulting dose-volume histograms were analyzed for the two groups of structures. Data analysis shows statistically significant differences in the main parameters used to assess the risk of toxicity of a prostate radiotherapy treatment. Higher doses were received on the rectal and bladder walls compared to doses received on the corresponding solid organs. The observed differences in terms of received doses to the rectum and bladder based on the method of contouring could gain greater importance in inverse planning treatments, where the treatment planning system optimizes the dose in these volumes. So, one should take into account the method of delineating of these structures to make a clinical decision regarding dose limitation and risk assessment of chronic toxicity.

Effects of non-invasive ventilation and posture on chest wall volumes and motion in patients with amyotrophic lateral sclerosis: a case series

PubMed Central

Magalhães, Cristiana M.; Fregonezi, Guilherme A.; Vidigal-Lopes, Mauro; Vieira, Bruna S. P. P.; Vieira, Danielle S. R.; Parreira, Verônica F.

2016-01-01

ABSTRACT Background The effects of non-invasive ventilation (NIV) on the breathing pattern and thoracoabdominal motion of patients with amyotrophic lateral sclerosis (ALS) are unknown. Objectives 1) To analyze the influence of NIV on chest wall volumes and motion assessed by optoelectronic plethysmography in ALS patients and 2) to compare these parameters in the supine and sitting positions to those of healthy individuals (without NIV). Method Nine ALS patients were evaluated in the supine position using NIV. In addition, the ALS patients and nine healthy individuals were evaluated in both sitting and supine positions. Statistical analysis was performed using the paired Student t-test or Wilcoxon test and the Student t-test for independent samples or Mann-Whitney U test. Results Chest wall volume increased significantly with NIV, mean volume=0.43 (SD=0.16)L versus 0.57 (SD=0.19)L (p=0.04). No significant changes were observed for the pulmonary rib cage, abdominal rib cage, or abdominal contribution. The index of the shortening velocity of the diaphragmatic muscle, mean=0.15 (SD=0.05)L/s versus 0.21 (SD=0.05)L/s (p<0.01), and abdominal muscles, mean=0.09 (SD=0.02)L/s versus 0.14 (SD=0.06)L/s (p<0.01), increased during NIV. Comparisons between the supine and sitting positions showed similar changes in chest wall motion in both groups. However, the ALS patients presented a significantly lower contribution of the abdomen in the supine position compared with the controls, mean=56 (SD=13) versus 69 (SD=10) (p=0.02). Conclusions NIV improved chest wall volumes without changing the contribution of the chest wall compartment in ALS patients. In the supine position, ALS patients had a lower contribution of the abdomen, which may indicate early diaphragmatic dysfunction. PMID:27556390

Effects of non-invasive ventilation and posture on chest wall volumes and motion in patients with amyotrophic lateral sclerosis: a case series.

PubMed

Magalhães, Cristiana M; Fregonezi, Guilherme A; Vidigal-Lopes, Mauro; Vieira, Bruna S P P; Vieira, Danielle S R; Parreira, Verônica F

2016-01-01

The effects of non-invasive ventilation (NIV) on the breathing pattern and thoracoabdominal motion of patients with amyotrophic lateral sclerosis (ALS) are unknown. 1) To analyze the influence of NIV on chest wall volumes and motion assessed by optoelectronic plethysmography in ALS patients and 2) to compare these parameters in the supine and sitting positions to those of healthy individuals (without NIV). Nine ALS patients were evaluated in the supine position using NIV. In addition, the ALS patients and nine healthy individuals were evaluated in both sitting and supine positions. Statistical analysis was performed using the paired Student t-test or Wilcoxon test and the Student t-test for independent samples or Mann-Whitney U test. Chest wall volume increased significantly with NIV, mean volume=0.43 (SD=0.16)L versus 0.57 (SD=0.19)L (p=0.04). No significant changes were observed for the pulmonary rib cage, abdominal rib cage, or abdominal contribution. The index of the shortening velocity of the diaphragmatic muscle, mean=0.15 (SD=0.05)L/s versus 0.21 (SD=0.05)L/s (p<0.01), and abdominal muscles, mean=0.09 (SD=0.02)L/s versus 0.14 (SD=0.06)L/s (p<0.01), increased during NIV. Comparisons between the supine and sitting positions showed similar changes in chest wall motion in both groups. However, the ALS patients presented a significantly lower contribution of the abdomen in the supine position compared with the controls, mean=56 (SD=13) versus 69 (SD=10) (p=0.02). NIV improved chest wall volumes without changing the contribution of the chest wall compartment in ALS patients. In the supine position, ALS patients had a lower contribution of the abdomen, which may indicate early diaphragmatic dysfunction.

West wall, display area (room 101), view 1 of 4: ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

West wall, display area (room 101), view 1 of 4: southwest corner, showing stairs to commander's quarters and viewing bridge, windows to controller's room (room 102), south end of control consoles, and holes in pedestal floor for computer equipment cables (tape drive I/O?) - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

Crack opening area estimates in pressurized through-wall cracked elbows under bending

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

Franco, C.; Gilles, P.; Pignol, M.

1997-04-01

One of the most important aspects in the leak-before-break approach is the estimation of the crack opening area corresponding to potential through-wall cracks at critical locations during plant operation. In order to provide a reasonable lower bound to the leak area under such loading conditions, numerous experimental and numerical programs have been developed in USA, U.K. and FRG and widely discussed in literature. This paper aims to extend these investigations on a class of pipe elbows characteristic of PWR main coolant piping. The paper is divided in three main parts. First, a new simplified estimation scheme for leakage area ismore » described, based on the reference stress method. This approach mainly developed in U.K. and more recently in France provides a convenient way to account for the non-linear behavior of the material. Second, the method is carried out for circumferential through-wall cracks located in PWR elbows subjected to internal pressure. Finite element crack area results are presented and comparisons are made with our predictions. Finally, in the third part, the discussion is extended to elbows under combined pressure and in plane bending moment.« less

Exposure to chronic alcohol accelerates development of wall stress and eccentric remodeling in rats with volume overload.

PubMed

Mouton, Alan J; Ninh, Van K; El Hajj, Elia C; El Hajj, Milad C; Gilpin, Nicholas W; Gardner, Jason D

2016-08-01

Chronic alcohol abuse is one of the leading causes of dilated cardiomyopathy (DCM) in the United States. Volume overload (VO) also produces DCM characterized by left ventricular (LV) dilatation and reduced systolic and diastolic function, eventually progressing to congestive heart failure. For this study, we hypothesized that chronic alcohol exposure would exacerbate cardiac dysfunction and remodeling due to VO. Aortocaval fistula surgery was used to induce VO, and compensatory cardiac remodeling was allowed to progress for either 3days (acute) or 8weeks (chronic). Alcohol was administered via chronic intermittent ethanol vapor (EtOH) for 2weeks before the acute study and for the duration of the 8week chronic study. Temporal alterations in LV function were assessed by echocardiography. At the 8week end point, pressure-volume loop analysis was performed by LV catheterization and cardiac tissue collected. EtOH did not exacerbate LV dilatation (end-systolic and diastolic diameter) or systolic dysfunction (fractional shortening, ejection fraction) due to VO. The combined stress of EtOH and VO decreased the eccentric index (posterior wall thickness to end-diastolic diameter ratio), increased end-diastolic pressure (EDP), and elevated diastolic wall stress. VO also led to increases in posterior wall thickness, which was not observed in the VO+EtOH group, and wall thickness significantly correlated with LV BNP expression. VO alone led to increases in interstitial collagen staining (picrosirius red), which while not statistically significant, tended to be decreased by EtOH. VO increased LV collagen I protein expression, whereas in rats with VO+EtOH, LV collagen I was not elevated relative to Sham. The combination of VO and EtOH also led to increases in LV collagen III expression relative to Sham. Rats with VO+EtOH had significantly lower collagen I/III ratio than rats with VO alone. During the acute remodeling phase of VO (3days), VO significantly increased collagen III

Impact of the radiotherapy technique on the correlation between dose-volume histograms of the bladder wall defined on MRI imaging and dose-volume/surface histograms in prostate cancer patients

NASA Astrophysics Data System (ADS)

Maggio, Angelo; Carillo, Viviana; Cozzarini, Cesare; Perna, Lucia; Rancati, Tiziana; Valdagni, Riccardo; Gabriele, Pietro; Fiorino, Claudio

2013-04-01

The aim of this study was to evaluate the correlation between the ‘true’ absolute and relative dose-volume histograms (DVHs) of the bladder wall, dose-wall histogram (DWH) defined on MRI imaging and other surrogates of bladder dosimetry in prostate cancer patients, planned both with 3D-conformal and intensity-modulated radiation therapy (IMRT) techniques. For 17 prostate cancer patients, previously treated with radical intent, CT and MRI scans were acquired and matched. The contours of bladder walls were drawn by using MRI images. External bladder surfaces were then used to generate artificial bladder walls by performing automatic contractions of 5, 7 and 10 mm. For each patient a 3D conformal radiotherapy (3DCRT) and an IMRT treatment plan was generated with a prescription dose of 77.4 Gy (1.8 Gy/fr) and DVH of the whole bladder of the artificial walls (DVH-5/10) and dose-surface histograms (DSHs) were calculated and compared against the DWH in absolute and relative value, for both treatment planning techniques. A specific software (VODCA v. 4.4.0, MSS Inc.) was used for calculating the dose-volume/surface histogram. Correlation was quantified for selected dose-volume/surface parameters by the Spearman correlation coefficient. The agreement between %DWH and DVH5, DVH7 and DVH10 was found to be very good (maximum average deviations below 2%, SD < 5%): DVH5 showed the best agreement. The correlation was slightly better for absolute (R = 0.80-0.94) compared to relative (R = 0.66-0.92) histograms. The DSH was also found to be highly correlated with the DWH, although slightly higher deviations were generally found. The DVH was not a good surrogate of the DWH (R < 0.7 for most of parameters). When comparing the two treatment techniques, more pronounced differences between relative histograms were seen for IMRT with respect to 3DCRT (p < 0.0001).

Preliminary Results Of Hydrodynamic Responses To Ship Movements And Weather Conditions Along The Coastal Walls Of Shallow Areas

NASA Astrophysics Data System (ADS)

Acar, Dursun; Alpar, Bedri; Cagatay, Namık; Ozeren, Sinan; Sarı, Erol; Eris, Kadir; Vardar, Denizhan; Arslan, Tugce; Basegmez, Koray

2016-04-01

flat bases. The spreading properties of water volumes together with the water level differences along the coastal walls were measured under the influence of a linear-turbine fan positioned above the model to simulate the dynamic wind pressure. The most severe water distributions and highest water-level losses have been observed on the model with +60° angular walls. Contrary, the model with reverse sloped (-60°) seawalls demonstrated the most oscillating level at the coast but has kept the water-level rather stable in the central part. This causes the waves to be reflected back to the wall as fast as it has been observed during the experiment. If compared to the other structures such a construction is quite costly to be made. However, the water depth in this model has been preserved at the shallow areas, since it is able to reflect the waves and its energy-absorbing feature is good with less "Ekman Condition" effect. Keywords: Shallow channel, coastal waters, atmospheric pressure, Ekman Condition, squat

Minerals Yearbook, volume II, Area Reports—Domestic

USGS Publications Warehouse

,

2018-01-01

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included.Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals.Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section.The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

Minerals Yearbook, volume III, Area Reports—International

USGS Publications Warehouse

,

2018-01-01

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included.Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals.Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section.The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

Intracranial arterial wall imaging using three-dimensional high isotropic resolution black blood MRI at 3.0 Tesla.

PubMed

Qiao, Ye; Steinman, David A; Qin, Qin; Etesami, Maryam; Schär, Michael; Astor, Brad C; Wasserman, Bruce A

2011-07-01

To develop a high isotropic-resolution sequence to evaluate intracranial vessels at 3.0 Tesla (T). Thirteen healthy volunteers and 4 patients with intracranial stenosis were imaged at 3.0T using 0.5-mm isotropic-resolution three-dimensional (3D) Volumetric ISotropic TSE Acquisition (VISTA; TSE, turbo spin echo), with conventional 2D-TSE for comparison. VISTA was repeated for 6 volunteers and 4 patients at 0.4-mm isotropic-resolution to explore the trade-off between SNR and voxel volume. Wall signal-to-noise-ratio (SNR(wall) ), wall-lumen contrast-to-noise-ratio (CNR(wall-lumen) ), lumen area (LA), wall area (WA), mean wall thickness (MWT), and maximum wall thickness (maxWT) were compared between 3D-VISTA and 2D-TSE sequences, as well as 3D images acquired at both resolutions. Reliability was assessed by intraclass correlations (ICC). Compared with 2D-TSE measurements, 3D-VISTA provided 58% and 74% improvement in SNR(wall) and CNR(wall-lumen) , respectively. LA, WA, MWT and maxWT from 3D and 2D techniques highly correlated (ICCs of 0.96, 0.95, 0.96, and 0.91, respectively). CNR(wall-lumen) using 0.4-mm resolution VISTA decreased by 27%, compared with 0.5-mm VISTA but with reduced partial-volume-based overestimation of wall thickness. Reliability for 3D measurements was good to excellent. The 3D-VISTA provides SNR-efficient, highly reliable measurements of intracranial vessels at high isotropic-resolution, enabling broad coverage in a clinically acceptable time. Copyright © 2011 Wiley-Liss, Inc.

Cell Wall Remodeling Enzymes Modulate Fungal Cell Wall Elasticity and Osmotic Stress Resistance

PubMed Central

Ene, Iuliana V.; Walker, Louise A.; Schiavone, Marion; Lee, Keunsook K.; Martin-Yken, Hélène; Dague, Etienne; Gow, Neil A. R.; Munro, Carol A.

2015-01-01

ABSTRACT The fungal cell wall confers cell morphology and protection against environmental insults. For fungal pathogens, the cell wall is a key immunological modulator and an ideal therapeutic target. Yeast cell walls possess an inner matrix of interlinked β-glucan and chitin that is thought to provide tensile strength and rigidity. Yeast cells remodel their walls over time in response to environmental change, a process controlled by evolutionarily conserved stress (Hog1) and cell integrity (Mkc1, Cek1) signaling pathways. These mitogen-activated protein kinase (MAPK) pathways modulate cell wall gene expression, leading to the construction of a new, modified cell wall. We show that the cell wall is not rigid but elastic, displaying rapid structural realignments that impact survival following osmotic shock. Lactate-grown Candida albicans cells are more resistant to hyperosmotic shock than glucose-grown cells. We show that this elevated resistance is not dependent on Hog1 or Mkc1 signaling and that most cell death occurs within 10 min of osmotic shock. Sudden decreases in cell volume drive rapid increases in cell wall thickness. The elevated stress resistance of lactate-grown cells correlates with reduced cell wall elasticity, reflected in slower changes in cell volume following hyperosmotic shock. The cell wall elasticity of lactate-grown cells is increased by a triple mutation that inactivates the Crh family of cell wall cross-linking enzymes, leading to increased sensitivity to hyperosmotic shock. Overexpressing Crh family members in glucose-grown cells reduces cell wall elasticity, providing partial protection against hyperosmotic shock. These changes correlate with structural realignment of the cell wall and with the ability of cells to withstand osmotic shock. PMID:26220968

Osmosis and Surface Area to Volume Ratio.

ERIC Educational Resources Information Center

Barrett, D. R. B.

1984-01-01

Describes an experiment designed to help students understand the concepts of osmosis and surface area to volume ratio (SA:VOL). The task for students is to compare water uptake in different sizes of potato cubes and relate differences to their SA:VOL ratios. (JN)

OPS MCC level B/C formulation requirements: Area targets and space volumes processor

NASA Technical Reports Server (NTRS)

Bishop, M. J., Jr.

1979-01-01

The level B/C mathematical specifications for the area targets and space volumes processor (ATSVP) are described. The processor is designed to compute the acquisition-of-signal (AOS) and loss-of-signal (LOS) times for area targets and space volumes. The characteristics of the area targets and space volumes are given. The mathematical equations necessary to determine whether the spacecraft lies within the area target or space volume are given. These equations provide a detailed model of the target geometry. A semianalytical technique for predicting the AOS and LOS time periods is disucssed. This technique was designed to bound the actual visibility period using a simplified target geometry model and unperturbed orbital motion. Functional overview of the ATSVP is presented and it's detailed logic flow is described.

Normal reference values for bladder wall thickness on CT in a healthy population.

PubMed

Fananapazir, Ghaneh; Kitich, Aleksandar; Lamba, Ramit; Stewart, Susan L; Corwin, Michael T

2018-02-01

To determine normal bladder wall thickness on CT in patients without bladder disease. Four hundred and nineteen patients presenting for trauma with normal CTs of the abdomen and pelvis were included in our retrospective study. Bladder wall thickness was assessed, and bladder volume was measured using both the ellipsoid formula and an automated technique. Patient age, gender, and body mass index were recorded. Linear regression models were created to account for bladder volume, age, gender, and body mass index, and the multiple correlation coefficient with bladder wall thickness was computed. Bladder volume and bladder wall thickness were log-transformed to achieve approximate normality and homogeneity of variance. Variables that did not contribute substantively to the model were excluded, and a parsimonious model was created and the multiple correlation coefficient was calculated. Expected bladder wall thickness was estimated for different bladder volumes, and 1.96 standard deviation above expected provided the upper limit of normal on the log scale. Age, gender, and bladder volume were associated with bladder wall thickness (p = 0.049, 0.024, and < 0.001, respectively). The linear regression model had an R 2 of 0.52. Age and gender were negligible in contribution to the model, and a parsimonious model using only volume was created for both the ellipsoid and automated volumes (R 2  = 0.52 and 0.51, respectively). Bladder wall thickness correlates with bladder wall volume. The study provides reference bladder wall thicknesses on CT utilizing both the ellipsoid formula and automated bladder volumes.

Evolution of domain walls in the early universe. Ph.D. Thesis - Chicago Univ.

NASA Technical Reports Server (NTRS)

Kawano, Lawrence

1989-01-01

The evolution of domain walls in the early universe is studied via 2-D computer simulation. The walls are initially configured on a triangular lattice and then released from the lattice, their evolution driven by wall curvature and by the universal expansion. The walls attain an average velocity of about 0.3c and their surface area per volume (as measured in comoving coordinates) goes down with a slope of -1 with respect to conformal time, regardless of whether the universe is matter or radiation dominated. The additional influence of vacuum pressure causes the energy density to fall away from this slope and steepen, thus allowing a situation in which domain walls can constitute a significant portion of the energy density of the universe without provoking an unacceptably large perturbation upon the microwave background.

Application of soil block without burning process and calcium silicate panels as building wall in mountainous area

NASA Astrophysics Data System (ADS)

Noerwasito, Vincentius Totok; Nasution, Tanti Satriana Rosary

2017-11-01

Utilization of local building materials in a residential location in mountainous area is very important, considering local material as a low-energy building material because of low transport energy. The local building materials used in this study are walls made from soil blocks. The material was made by the surrounding community from compacted soil without burning process. To maximize the potential of soil block to the outdoor temperature in the mountains, it is necessary to add non-local building materials as an insulator from the influence of the outside air. The insulator was calcium silicate panel. The location of the research is Trawas sub-district, Mojokerto regency, which is a mountainous area. The research problem is on applying the composition of local materials and calcium silicate panels that it will be able to meet the requirements as a wall building material and finding to what extent the impact of the wall against indoor temperature. The result from this research was the application of soil block walls insulated by calcium silicate panels in a building model. Besides, because of the utilization of those materials, the building has a specific difference between indoor and outdoor temperature. Thus, this model can be applied in mountainous areas in Indonesia.

Urban area and green space: volume estimation using medium resolution satellite imagery

NASA Astrophysics Data System (ADS)

Handayani, H. H.

2017-12-01

The latest revision of the UN World Urbanization Prospects predicts the world's urban population to increase by 1.4 billion between 2010 and 2030, 60% of the population will live in cities. Consequently, this expansion affects the existence of ecosystem services in the context of sustainability environment. Green space is a focal point of the ecological system and is affected by the urbanization process. The green space has essential functions in cleaning the water, adjusting the microclimate, eliminating noise, and beautifying the surrounding makes the green quantity as well as quality very vital to its existence. The urban expansion leads the growth into vertical development. Therefore, the third dimension using urban volume as an indicator of vertical development is introduced. Therefore, this study estimates the urban and green volume by using medium resolution remote sensing. Surabaya is used as a case study since the city has grown up significantly in both of population and capital investment in this decade. Here, urban and green volume is investigated by ALOS datasets with urban referring built-up. Also, we examine the area with low and high green volume by performing hot and cold spots analysis. The average of built-up volume reaches 173.05 m3/pixel presented by the building for a residential single house with the height less than 7m. The average of green volume is 14.74m3/pixel performed by the vegetation with the height generally 0.6 to 1m which is frequently planted in the backyard of house. However, the ratio of green volume to the built-up volume shows a small portion which is around 8.52%. Therefore, we identify the hot and cold spots, we evaluate 5 areas having cold spot regarding lack of green volume. The two locations of cold spot are located in the northern part and another is in the southern part. Those areas have high number of built-up volume which is in particularly as sub-CBD area. We emphasize that the improvement of green quantity is needed

Scale resolving computation of submerged wall jets on flat wall with different roughness heights

NASA Astrophysics Data System (ADS)

Paik, Joongcheol; Bombardelli, Fabian

2014-11-01

Scale-adaptive simulation is used to investigate the response of velocity and turbulence in submerged wall jets to abrupt changes from smooth to rough beds. The submerged wall jets were experimentally investigated by Dey and Sarkar [JFM, 556, 337, 2006] at the Reynolds number of 17500 the Froude number of 4.09 and the submergence ratio of 1.12 on different rough beds that were generated by uniform sediments of different median diameters The SAS is carried out by means of a second-order-accurate finite volume method in space and time and the effect of bottom roughness is treated by the approach of Cebeci (2004). The evolution of free surface is captured by employing the two-phase volume of fluid (VOF) technique. The numerical results obtained by the SAS approach, incorporated with the VOF and the rough wall treatment, are in good agreement with the experimental measurements. The computed turbulent boundary layer grows more quickly and the depression of the free surface is more increased on the rough wall than those on smooth wall. The size of the fully developed zone shrinks and the decay rate of maximum streamwise velocity and Reynolds stress components are faster with increase in the wall roughness. Supported by NSF and NRF of Korea.

Respiratory kinematics by optoelectronic analysis of chest-wall motion and ultrasonic imaging of the diaphragm

NASA Astrophysics Data System (ADS)

Aliverti, Andrea; Pedotti, Antonio; Ferrigno, Giancarlo; Macklem, P. T.

1998-07-01

Although from a respiratory point of view, compartmental volume change or lack of it is the most crucial variable, it has not been possible to measure the volume of chest wall compartments directly. Recently we developed a new method based on a optoelectronic motion analyzer that can give the three-dimensional location of many markers with the temporal and spatial accuracy required for respiratory measurements. Marker's configuration has been designed specifically to measure the volume of three chest wall compartments, the pulmonary and abdominal rib cage compartments and the abdomen, directly. However, it can not track the exact border between the two rib cage compartments (pulmonary and abdominal) which is determined by the cephalic extremity of the area of apposition of the diaphragm to the inner surface of the rib cage, and which can change systematically as a result of disease processes. The diaphragm displacement can be detected by ultrasonography. In the present study, we propose an integrated system able to investigate the relationships between external (chest wall) and internal (diaphragm) movements of the different respiratory structures by simultaneous external imaging with the optoelectronic system combined with internal kinematic imaging using ultrasounds. 2D digitized points belonging to the lower lung margin, taken from ultrasonographic views, are mapped into the 3D space, where chest wall markers are acquired. Results are shown in terms of accuracy of 3D probe location, relative movement between the probe and the body landmarks, dynamic relationships between chest wall volume and position of the diaphragm during quiet breathing, slow inspirations, relaxations and exercise.

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.

Comparative study of collagen deposition in the colon wall of patients operated for sigmoid diverticular disease.

PubMed

Pantaroto, Mário; Lopes Filho, Gaspar de Jesus; Pinto, Clovis Antonio Lopes; Antico Filho, Armando

2015-10-01

To investigate the deposition of collagen in the colon wall of patients with sigmoid diverticulitis. Samples of sigmoid tissue from 15 patients (disease group), seven men and eight women aged 37-77 years who underwent surgery for the treatment of diverticulitis, were selected. For the control group, specimens from five patients, three men and two women aged 19-58 years undergoing emergency surgery for sigmoid trauma were selected. These subjects had no associated diseases. The histological study of the surgical specimens was performed by staining with hematoxylin-eosin and picrosirius and using a histochemical method for collagen quantification. Collagen deposition in the colon wall in terms of area (F), glandular epithelium (E) and total area was significantly higher in the disease group compared to control (p=0.003, p=0.026 and p=0.010, respectively). The collagen volume fraction (F fraction) and muscle tissue (M fraction) were also significantly higher compared to control (p=0.044 and p=0.026, respectively). The muscle (M area) and volume fraction of glandular epithelium (E fraction) did not differ significantly between the two groups, (p=0.074 and p=1.000, respectively). In this study, collagen deposition in the colon wall of the patients operated for sigmoid diverticulitis was higher compared to patients without the disease.

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.

Guard cells elongate: relationship of volume and surface area during stomatal movement.

PubMed

Meckel, Tobias; Gall, Lars; Semrau, Stefan; Homann, Ulrike; Thiel, Gerhard

2007-02-01

Stomata in the epidermis of photosynthetically active plant organs are formed by pairs of guard cells, which create a pore, to facilitate CO2 and water exchange with the environment. To control this gas exchange, guard cells actively change their volume and, consequently, surface area to alter the aperture of the stomatal pore. Due to the limited elasticity of the plasma membrane, such changes in surface area require an exocytic addition or endocytic retrieval of membrane during stomatal movement. Using confocal microscopic data, we have reconstructed detailed three-dimensional models of open and closed stomata to precisely quantify the necessary area to be exo- and endocytosed by the guard cells. Images were obtained under a strong emphasis on a precise calibration of the method and by avoiding unphysiological osmotical imbalance, and hence osmocytosis. The data reveal that guard cells of Vicia faba L., whose aperture increases by 111.89+/-22.39%, increase in volume and surface area by 24.82+/-6.26% and 14.99+/-2.62%, respectively. In addition, the precise volume to surface area relationship allows quantitative modeling of the three-dimensional changes. While the major volume change is caused by a slight increase in the cross section of the cells, an elongation of the guard cells achieves the main aperture change.

Stem Cubic-Foot Volume Tables for Tree Species in the Appalachian Area

Treesearch

Alexander Clark; Ray A. Souter

1996-01-01

Stemwood cubic-foot volume inside bark tables are presented for 20 species and 8 species groups based on equations used to estimate timber sale volumes on national forests in the Appalachian Area. Tables are based on form class measurement data for 2,870 trees sampled in the Appalachian Area and taper data collected across the South. A series of tables is presented...

Vortex Imprints at the Wall, But Not in the Bulk, Distinguish Ruptured from Unruptured Intracranial Aneurysms

NASA Astrophysics Data System (ADS)

Varble, Nicole; Meng, Hui

2015-11-01

Intracranial aneurysms affect 3% of the population. Risk stratification of aneurysms is important, as rupture often leads to death or permanent disability. Image-based CFD analyses of patient-specific aneurysms have identified low and oscillatory wall shear stress to predict rupture. These stresses are sensed biologically at the luminal wall, but the flow dynamics related to aneurysm rupture requires further understanding. We have conducted two studies: one examines vortex dynamics, and the other, high frequency flow fluctuations in patient-specific aneurysms. In the first study, based on Q-criterion vortex identification, we developed two measures to quantify regions within the aneurysm where rotational flow is dominate: the ratio of volume or surface area where Q >0 vs. the total aneurysmal volume or surface area, respectively termed volume vortex fraction (VVF) and surface vortex fraction (SVF). Statistical analysis of 204 aneurysms shows that SVF, but not VVF, distinguishes ruptured from unruptured aneurysms, suggesting that once again, the local flow patterns on the wall is directly relevant to rupture. In the second study, high-resolution CFD (high spatial and temporal resolutions and second-order discretization schemes) on 56 middle cerebral artery aneurysms shows the presence of temporal fluctuations in 8 aneurysms, but such flow instability bears no correlation with rupture. Support for this work was partially provided by NIH grant (R01 NS091075-01) and a grant from Toshiba Medical Systems Corp.

Skyrmions from Instantons inside Domain Walls

NASA Astrophysics Data System (ADS)

Eto, Minoru; Nitta, Muneto; Ohashi, Keisuke; Tong, David

2005-12-01

Some years ago, Atiyah and Manton described a method to construct approximate Skyrmion solutions from Yang-Mills instantons. Here we present a dynamical realization of this construction using domain walls in a five-dimensional gauge theory. The non-Abelian gauge symmetry is broken in each vacuum but restored in the core of the domain wall, allowing instantons to nestle inside the wall. We show that the world volume dynamics of the wall is given by the Skyrme model, including the four-derivative term, and the instantons appear as domain wall Skyrmions.

Stem Cubic-Volume Tables for Tree Species in the Deep South Area

Treesearch

Alexander Clark; Ray A. Souter

1996-01-01

Stemwood cubic-foot volume inside bark tables are presented for 21 species and 8 species groups based on equations used to estimate timber sale volumes on national forests in the Deep South Area. Tables are based on form class measurement data for 2,390 trees sampled in the Deep South Area and taper data collected across the South. A series of tables is presented for...

Stem Cubic-Foot Volume Tables for Tree Species in the Arkansas Area

Treesearch

Alexander Clark; Ray A. Souter

1996-01-01

Stemwood cubic-foot volume inside bark tables are presented for 9 species and 6 species groups based on equations used to estimate timber sale volumes on national forests in the Arkansas Area. Tables are based on form class measurement data for 1,417 trees sampled in the Arkansas Area and taper data collected across the South. A series of tables is presented for each...

Stem Cubic-Foot Volume Tabies for Tree Species in the Delta Area

Treesearch

Alexander Clark; Ray A. Souter

1996-01-01

Stemwood cubic-foot volume inside bark tables are presented for 13 species and 8 species groups based on equations used to estimate timber sale volumes on national forests in the Delta Area. Tables are based on form class measurement data for 990 trees sampled in the Delta Area and taper data collected across the South. A series of tables is presented for each species...

Research on wall shear stress considering wall roughness when shear swirling flow vibration cementing

NASA Astrophysics Data System (ADS)

Cui, Zhihua; Ai, Chi; Feng, Fuping

2017-01-01

When shear swirling flow vibration cementing, the casing is revolving periodically and eccentrically, which leads to the annulus fluid in turbulent swirling flow state. The wall shear stress is more than that in laminar flow field when conventional cementing. The paper mainly studied the wall shear stress distribution on the borehole wall when shear swirling flow vibration cementing based on the finite volume method. At the same time, the wall roughness affected and changed the turbulent flow near the borehole wall and the wall shear stress. Based on the wall function method, the paper established boundary conditions considering the wall roughness and derived the formula of the wall shear stress. The results showed that the wall roughness significantly increases the wall shear stress. However, the larger the wall roughness, the greater the thickness of mud cake, which weakening the cementing strength. Considering the effects in a comprehensive way, it is discovered that the particle size of solid phase in drilling fluid is about 0.1 mm to get better cementing quality.

Randomized, controlled pilot study comparing large-volume paracentesis using wall suction and traditional glass vacuum bottle methods.

PubMed

Konerman, Monica A; Price, Jennifer; Torres, Dawn; Li, Zhiping

2014-09-01

Large-volume paracentesis (LVP) can be time and labor intensive depending on the amount of ascites removed and the method of drainage. Wall suction has been adopted as the preferred method of drainage at many centers, though the safety and benefits of this technique have not been formally evaluated. The primary objective of this study was to define the cost and time savings of wall suction over the traditional glass vacuum bottle method for ascites drainage. The secondary objective was to compare the safety profile and patient satisfaction using these two techniques. We conducted a randomized, controlled pilot study of the wall suction versus vacuum bottle methods for LVP in hospitalized patients. All LVPs were performed under ultrasound guidance by a single proceduralist. Patients with at least 4 liters removed received 25% intravenous albumin, 8 g/liter fluid removed. Demographic, clinical characteristics, and procedure details were recorded. Laboratory and hemodynamic data were recorded for 24 h prior to and 24-48 h post LVP. An electronic chart review was conducted to evaluate procedure-related complications. Data were compared using Fisher's exact test, t test, or Mann-Whitney U test. Thirty-four patients were randomized to wall suction at 200 mmHg (n = 17) or glass vacuum bottle drainage (n = 17). Wall suction was significantly faster and less costly than vacuum bottle drainage (7 versus 15 min, p = 0.002; $4.59 versus $12.73, p < 0.001). There were no differences in outcomes at 24 and 48 h post LVP, or at 60-day follow up. Performing LVP using wall suction resulted in significantly shorter procedure time and supply cost savings. There were no differences in outcomes between the groups, suggesting equivalent safety, though larger studies powered to detect small differences are needed. Given its efficiency, convenience, and cost effectiveness, wall suction may be a superior method of ascites drainage for LVP.

Regular Topologies for Gigabit Wide-Area Networks. Volume 1

NASA Technical Reports Server (NTRS)

Shacham, Nachum; Denny, Barbara A.; Lee, Diane S.; Khan, Irfan H.; Lee, Danny Y. C.; McKenney, Paul

1994-01-01

In general terms, this project aimed at the analysis and design of techniques for very high-speed networking. The formal objectives of the project were to: (1) Identify switch and network technologies for wide-area networks that interconnect a large number of users and can provide individual data paths at gigabit/s rates; (2) Quantitatively evaluate and compare existing and proposed architectures and protocols, identify their strength and growth potentials, and ascertain the compatibility of competing technologies; and (3) Propose new approaches to existing architectures and protocols, and identify opportunities for research to overcome deficiencies and enhance performance. The project was organized into two parts: 1. The design, analysis, and specification of techniques and protocols for very-high-speed network environments. In this part, SRI has focused on several key high-speed networking areas, including Forward Error Control (FEC) for high-speed networks in which data distortion is the result of packet loss, and the distribution of broadband, real-time traffic in multiple user sessions. 2. Congestion Avoidance Testbed Experiment (CATE). This part of the project was done within the framework of the DARTnet experimental T1 national network. The aim of the work was to advance the state of the art in benchmarking DARTnet's performance and traffic control by developing support tools for network experimentation, by designing benchmarks that allow various algorithms to be meaningfully compared, and by investigating new queueing techniques that better satisfy the needs of best-effort and reserved-resource traffic. This document is the final technical report describing the results obtained by SRI under this project. The report consists of three volumes: Volume 1 contains a technical description of the network techniques developed by SRI in the areas of FEC and multicast of real-time traffic. Volume 2 describes the work performed under CATE. Volume 3 contains the source

Wall of fundamental constants

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

Olive, Keith A.; School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota, 55455; Peloso, Marco

2011-02-15

We consider the signatures of a domain wall produced in the spontaneous symmetry breaking involving a dilatonlike scalar field coupled to electromagnetism. Domains on either side of the wall exhibit slight differences in their respective values of the fine-structure constant, {alpha}. If such a wall is present within our Hubble volume, absorption spectra at large redshifts may or may not provide a variation in {alpha} relative to the terrestrial value, depending on our relative position with respect to the wall. This wall could resolve the contradiction between claims of a variation of {alpha} based on Keck/Hires data and of themore » constancy of {alpha} based on Very Large Telescope data. We derive the properties of the wall and the parameters of the underlying microscopic model required to reproduce the possible spatial variation of {alpha}. We discuss the constraints on the existence of the low-energy domain wall and describe its observational implications concerning the variation of the fundamental constants.« less

Cell Wall Remodeling Enzymes Modulate Fungal Cell Wall Elasticity and Osmotic Stress Resistance.

PubMed

Ene, Iuliana V; Walker, Louise A; Schiavone, Marion; Lee, Keunsook K; Martin-Yken, Hélène; Dague, Etienne; Gow, Neil A R; Munro, Carol A; Brown, Alistair J P

2015-07-28

The fungal cell wall confers cell morphology and protection against environmental insults. For fungal pathogens, the cell wall is a key immunological modulator and an ideal therapeutic target. Yeast cell walls possess an inner matrix of interlinked β-glucan and chitin that is thought to provide tensile strength and rigidity. Yeast cells remodel their walls over time in response to environmental change, a process controlled by evolutionarily conserved stress (Hog1) and cell integrity (Mkc1, Cek1) signaling pathways. These mitogen-activated protein kinase (MAPK) pathways modulate cell wall gene expression, leading to the construction of a new, modified cell wall. We show that the cell wall is not rigid but elastic, displaying rapid structural realignments that impact survival following osmotic shock. Lactate-grown Candida albicans cells are more resistant to hyperosmotic shock than glucose-grown cells. We show that this elevated resistance is not dependent on Hog1 or Mkc1 signaling and that most cell death occurs within 10 min of osmotic shock. Sudden decreases in cell volume drive rapid increases in cell wall thickness. The elevated stress resistance of lactate-grown cells correlates with reduced cell wall elasticity, reflected in slower changes in cell volume following hyperosmotic shock. The cell wall elasticity of lactate-grown cells is increased by a triple mutation that inactivates the Crh family of cell wall cross-linking enzymes, leading to increased sensitivity to hyperosmotic shock. Overexpressing Crh family members in glucose-grown cells reduces cell wall elasticity, providing partial protection against hyperosmotic shock. These changes correlate with structural realignment of the cell wall and with the ability of cells to withstand osmotic shock. The C. albicans cell wall is the first line of defense against external insults, the site of immune recognition by the host, and an attractive target for antifungal therapy. Its tensile strength is conferred by

[Correlation analysis of cement leakage with volume ratio of intravertebral bone cement to vertebral body and vertebral body wall incompetence in percutaneous vertebroplasty for osteoporotic vertebral compression fractures].

PubMed

Liang, De; Ye, Linqiang; Jiang, Xiaobing; Huang, Weiquan; Yao, Zhensong; Tang, Yongchao; Zhang, Shuncong; Jin, Daxiang

2014-11-01

To investigate the risk factors of cement leakage in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fracture (OVCF). Between March 2011 and March 2012, 98 patients with single level OVCF were treated by PVP, and the clinical data were analyzed retrospectively. There were 13 males and 85 females, with a mean age of 77.2 years (range, 54-95 years). The mean disease duration was 43 days (range, 15-120 days), and the mean T score of bone mineral density (BMD) was -3.8 (range, -6.7- -2.5). Bilateral transpedicular approach was used in all the patients. The patients were divided into cement leakage group and no cement leakage group by occurrence of cement leakage based on postoperative CT. Single factor analysis was used to analyze the difference between 2 groups in T score of BMD, operative level, preoperative anterior compression degree of operative vertebrae, preoperative middle compression degree of operative vertebrae, preoperative sagittal Cobb angle of operative vertebrae, preoperative vertebral body wall incompetence, cement volume, and volume ratio of intravertebral bone cement to vertebral body. All relevant factors were introduced to logistic regression analysis to analyze the risk factors of cement leakage. All procedures were performed successfully. The mean operation time was 40 minutes (range, 30-50 minutes), and the mean volume ratio of intravertebral bone cement to vertebral body was 24.88% (range, 7.84%-38.99%). Back pain was alleviated significantly in all the patients postoperatively. All patients were followed up with a mean time of 8 months (range, 6-12 months). Cement leakage occurred in 49 patients. Single factor analysis showed that there were significant differences in the volume ratio of intravertebral bone cement to vertebral body and preoperative vertebral body wall incompetence between 2 groups (P < 0.05), while no significant difference in T score of BMD, operative level, preoperative anterior compression degree of

Epitympanum volume and tympanic isthmus area in temporal bones with retraction pockets.

PubMed

Monsanto, Rafael da Costa; Pauna, Henrique Furlan; Kaya, Serdar; Hızlı, Ömer; Kwon, Geeyoun; Paparella, Michael M; Cureoglu, Sebahattin

2016-11-01

To compare the volume of the epitympanic space, as well as the area of the tympanic isthmus, in human temporal bones with retraction pockets to those with chronic otitis media without retraction pockets and to those with neither condition. Comparative human temporal bone study. We generated a three-dimensional model of the bony epitympanum and measured the epitympanic space. We also compared the area of the tympanic isthmus. The mean total volume of the epitympanum was 40.55 ± 7.14 mm 3 in the retraction pocket group, 50.03 ± 8.49 mm 3 in the chronic otitis media group, and 48.03 ± 9.16 mm 3 in the neither condition group. The mean volume of the anterior, lateral, and medial compartments in temporal bones in the retraction pocket group was significantly smaller than in the two control groups (P < 0.05). Total epitympanic volume was also significantly smaller in the retraction pocket group than in both control groups (P < 0.05). The mean area of the tympanic isthmus was significantly smaller in the retraction pocket group (8.11 ± 2.44 mm 2 ) than in the chronic otitis media group (9.82 ± 2.06 mm 2 ) or the neither condition group (10.66 ± 1.78 mm 2 ) (P < 0.05). Our data indicate that temporal bones with retraction pockets have a smaller volume bony epitympanum and a smaller tympanic isthmus area as compared with temporal bones from both control groups. The smaller volume tympanic isthmus in the retraction pocket group may suggest that a blockage in the aeration pathways to the epitympanum could create dysventilation, resulting in negative pressure and ultimately in retraction pockets and cholesteatomas. NA Laryngoscope, 126:E369-E374, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Dynamics of chest wall volume regulation during constant work rate exercise in patients with chronic obstructive pulmonary disease

PubMed Central

Takara, L.S.; Cunha, T.M.; Barbosa, P.; Rodrigues, M.K.; Oliveira, M.F.; Nery, L.E.; Neder, J.A.

2012-01-01

This study evaluated the dynamic behavior of total and compartmental chest wall volumes [(VCW) = rib cage (VRC) + abdomen (VAB)] as measured breath-by-breath by optoelectronic plethysmography during constant-load exercise in patients with stable chronic obstructive pulmonary disease. Thirty males (GOLD stages II-III) underwent a cardiopulmonary exercise test to the limit of tolerance (Tlim) at 75% of peak work rate on an electronically braked cycle ergometer. Exercise-induced dynamic hyperinflation was considered to be present when end-expiratory (EE) VCW increased in relation to resting values. There was a noticeable heterogeneity in the patterns of VCW regulation as EEVCW increased non-linearly in 17/30 “hyperinflators” and decreased in 13/30 “non-hyperinflators” (P < 0.05). EEVAB decreased slightly in 8 of the “hyperinflators”, thereby reducing and slowing the rate of increase in end-inspiratory (EI) VCW (P < 0.05). In contrast, decreases in EEVCW in the “non-hyperinflators” were due to the combination of stable EEVRC with marked reductions in EEVAB. These patients showed lower EIVCW and end-exercise dyspnea scores but longer Tlim than their counterparts (P < 0.05). Dyspnea increased and Tlim decreased non-linearly with a faster rate of increase in EIVCW regardless of the presence or absence of dynamic hyperinflation (P < 0.001). However, no significant between-group differences were observed in metabolic, pulmonary gas exchange and cardiovascular responses to exercise. Chest wall volumes are continuously regulated during exercise in order to postpone (or even avoid) their migration to higher operating volumes in patients with COPD, a dynamic process that is strongly dependent on the behavior of the abdominal compartment. PMID:23250012

Behaviour of Masonry Walls under Horizontal Shear in Mining Areas

NASA Astrophysics Data System (ADS)

Kadela, Marta; Bartoszek, Marek; Fedorowicz, Jan

2017-12-01

The paper discusses behaviour of masonry walls constructed with small-sized elements under the effects of mining activity. It presents some mechanisms of damage occurring in such structures, its forms in real life and the behaviour of large fragments of masonry walls subjected to specific loads in FEM computational models. It offers a constitutive material model, which enables numerical analyses and monitoring of the behaviour of numerical models as regards elastic-plastic performance of the material, with consideration of its degradation. Results from the numerical analyses are discussed for isolated fragments of the wall subjected to horizontal shear, with consideration of degradation, impact of imposed vertical load as well as the effect of weakening of the wall, which was achieved by introducing openings in it, on the performance and deformation of the wall.

Parallel Microchannel-Based Measurements of Individual Erythrocyte Areas and Volumes

PubMed Central

Gifford, Sean C.; Frank, Michael G.; Derganc, Jure; Gabel, Christopher; Austin, Robert H.; Yoshida, Tatsuro; Bitensky, Mark W.

2003-01-01

We describe a microchannel device which utilizes a novel approach to obtain area and volume measurements on many individual red blood cells. Red cells are aspirated into the microchannels much as a single red blood cell is aspirated into a micropipette. Inasmuch as there are thousands of identical microchannels with defined geometry, data for many individual red cells can be rapidly acquired, and the fundamental heterogeneity of cell membrane biophysics can be analyzed. Fluorescent labels can be used to quantify red cell surface and cytosolic features of interest simultaneously with the measurement of area and volume for a given cell. Experiments that demonstrate and evaluate the microchannel measuring capabilities are presented and potential improvements and extensions are discussed. PMID:12524315

Ratio of Cut Surface Area to Leaf Sample Volume for Water Potential Measurements by Thermocouple Psychrometers

PubMed Central

Walker, Sue; Oosterhuis, Derrick M.; Wiebe, Herman H.

1984-01-01

Evaporative losses from the cut edge of leaf samples are of considerable importance in measurements of leaf water potential using thermocouple psychrometers. The ratio of cut surface area to leaf sample volume (area to volume ratio) has been used to give an estimate of possible effects of evaporative loss in relation to sample size. A wide range of sample sizes with different area to volume ratios has been used. Our results using Glycine max L. Merr. cv Bragg indicate that leaf samples with area to volume values less than 0.2 square millimeter per cubic millimeter give psychrometric leaf water potential measurements that compare favorably with pressure chamber measurements. PMID:16663578

The Archaeology of Coralville Lake, Iowa. Volume 4. Recreation Area Survey. (Interim Report 2).

DTIC Science & Technology

1985-09-01

THE ARCHAEOLOGY OF CORALVILLE LAKE, IOWA VOLUME IV: RECREATION AREA SURVEY (INTERIM REPORT II) p - [ JAN 1 4 1986 WAUWATOSA. WISCONSIN 86 1.13 117...THE ARCHAEOLOGY OF CORALVILLE LAKE, IOWA ; VOLUME IV: RECREATION AREA SURVEY (INTERIM REPORT II) Submitted To: Rock Island District Corps of Engineers...presents the results of intensive archaeological and geomorphic investigations at 14 special use or recreation areas at Coralville Lake, Iowa . The

Surface area and volume determination of subgingival calculus using laser fluorescence.

PubMed

Shakibaie, Fardad; Walsh, Laurence J

2014-03-01

Visible red (655 nm) laser fluorescence (LF) devices are currently used for identifying deposits of subgingival calculus on the root surfaces of teeth during dental examination and treatment; however, it is not known how the fluorescence readings produced by commercially available LF systems correlate to the nature of the deposits. This laboratory study explored the correlation between LF digital readings and the surface area and volume of subgingival calculus deposits on teeth. A collection of 30 extracted human posterior teeth with various levels of subgingival deposits of calculus across 240 sites were used in a clinical simulation, with silicone impression material used to replicate periodontal soft tissues. The teeth were scored by two examiners by using three commercial LF systems (DIAGNOdent, DIAGNOdent Pen and KEY3). The silicone was removed, and the teeth were removed for photography at × 20 magnification under white or ultraviolet light. The surface area, thickness, and volume were calculated, and both linear least squares regression and nonlinear (Spearman's rank method) correlation coefficients were determined. Visible red LF digital readings showed better correlation to calculus volume than to surface area. Overall, the best performance was found for the KEY3 system (Spearman coefficient 0.59), compared to the Classic DIAGNOdent (0.56) and the DIAGNOdent Pen (0.49). These results indicate that while visible red LF systems vary somewhat in performance, their LF readings provide a useful estimation of the volume of subgingival calculus deposits present on teeth.

Sub-hectare crop area mapped wall-to-wall in Tigray Ethiopia with HEC processing of WorldView sub-meter panchromatic image texture

NASA Astrophysics Data System (ADS)

Neigh, C. S. R.; Carroll, M.; Wooten, M.; McCarty, J. L.; Powell, B.; Husak, G. J.; Enenkel, M.; Hain, C.

2017-12-01

Global food production in the developing world occurs within sub-hectare fields that are difficult to identify with moderate resolution satellite imagery. Knowledge about the distribution of these fields is critical in food security programs. We developed a semi-automated image segmentation approach using wall-to-wall sub-meter imagery with high-end computing (HEC) to map crop area (CA) throughout Tigray, Ethiopia that encompasses over 41,000 km2. Our approach tested multiple HEC processing streams to reduce processing time and minimize mapping error. We applied multiple resolution smoothing kernels to capture differences in land surface texture associated to CA. Typically, very-small fields (mean < 2 ha) have a smooth image roughness compared to natural scrub/shrub woody vegetation at the 1 m scale and these features can be segmented in panchromatic imagery with multi-level histogram thresholding. We found multi-temporal very-high resolution (VHR) panchromatic imagery with multi-spectral VHR and moderate resolution imagery are sufficient in extracting critical CA information needed in food security programs. We produced a 2011 ‒ 2015 CA map using over 3,000 WorldView-1 panchromatic images wall-to-wall in 1/2° mosaics for Tigray, Ethiopia in 1 week. We evaluated CA estimates with nearly 3,000 WorldView-2 2 m multispectral 250 × 250 m image subsets, with seven expert interpretations, and with in-situ global positioning system (GPS) photography. Our CA estimates ranged from 32 to 41% in sub-regions of Tigray with median maximum per bin commission and omission errors of 11% and 1% respectively, with most of the error occurring in bins less than 15%. This empirical, simple, and low direct cost approach via U.S. government license agreement and HEC could be a viable big-data methodology to extract wall-to-wall CA for other regions of the world that have very-small agriculture fields with similar image texture.

Estimation of tunnel blockage from wall pressure signatures: A review and data correlation

NASA Technical Reports Server (NTRS)

Hackett, J. E.; Wilsden, D. J.; Lilley, D. E.

1979-01-01

A method is described for estimating low speed wind tunnel blockage, including model volume, bubble separation and viscous wake effects. A tunnel-centerline, source/sink distribution is derived from measured wall pressure signatures using fast algorithms to solve the inverse problem in three dimensions. Blockage may then be computed throughout the test volume. Correlations using scaled models or tests in two tunnels were made in all cases. In many cases model reference area exceeded 10% of the tunnel cross-sectional area. Good correlations were obtained regarding model surface pressures, lift drag and pitching moment. It is shown that blockage-induced velocity variations across the test section are relatively unimportant but axial gradients should be considered when model size is determined.

Temporal changes in nitrogen adsorption properties of single-walled carbon nanotubes

USGS Publications Warehouse

Agnihotri, S.; Rostam-Abadi, M.; Rood, M.J.

2004-01-01

Temporal evolution of N2 adsorption (77 K) properties of as-produced and purified single-walled nanotubes (SWNTs) samples is described here. The N2 adsorption isotherms are used to characterize the samples' surface areas and porosities. The as-produced samples demonstrate a temporal increase in surface area and pore volumes for up to 16 months. The purified samples, however, reached their stable values of surface area and pore volumes within four to seven months. N2 adsorption capacity of the purified SWNTs also increased when the fresh samples were subjected to thermal pre-processing, with diminishing changes in adsorption capacity with increased age. These observations indicate that the freshly prepared SWNTs, both as-produced and purified, were in an unstable state with their porosity changing with increasing sample age and thermal treatments. It is hypothesized that SWNTs undergo slow but progressive changes in their surface chemistry which causes their N2 adsorption properties to change over several months. ?? 2004 Elsevier Ltd. All rights reserved.

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ENTITLED - DOMAIN WALL FERMIONS AT TEN YEARS (VOLUME 84)

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

BLUM,T.; SONI,A.

The workshop was held to mark the 10th anniversary of the first numerical simulations of QCD using domain wall fermions initiated at BNL. It is very gratifying that in the intervening decade widespread use of domain wall and overlap fermions is being made. It therefore seemed appropriate at this stage for some ''communal introspection'' of the progress that has been made, hurdles that need to be overcome, and physics that can and should be done with chiral fermions. The meeting was very well attended, drawing about 60 registered participants primarily from Europe, Japan and the US. It was quite remarkablemore » that pioneers David Kaplan, Herbert Neuberger, Rajamani Narayanan, Yigal Shamir, Sinya Aoki, and Pavlos Vranas all attended the workshop. Comparisons between domain wall and overlap formulations, with their respective advantages and limitations, were discussed at length, and a broad physics program including pion and kaon physics, the epsilon regime, nucleon structure, and topology, among others, emerged. New machines and improved algorithms have played a key role in realizing realistic dynamical fermion lattice simulations (small quark mass, large volume, and so on), so much in fact that measurements are now as costly. Consequently, ways to make the measurements more efficient were also discussed. We were very pleased to see the keen and ever growing interest in chiral fermions in our community and the significant strides our colleagues have made in bringing chiral fermions to the fore of lattice QCD calculations. Their contributions made the workshop a success, and we thank them deeply for sharing their time and ideas. Finally, we must especially acknowledge Norman Christ and Bob Mawhinney for their early and continued collaboration without which the success of domain wall fermions would not have been possible.« less

Volume calculation of CT lung lesions based on Halton low-discrepancy sequences

NASA Astrophysics Data System (ADS)

Li, Shusheng; Wang, Liansheng; Li, Shuo

2017-03-01

Volume calculation from the Computed Tomography (CT) lung lesions data is a significant parameter for clinical diagnosis. The volume is widely used to assess the severity of the lung nodules and track its progression, however, the accuracy and efficiency of previous studies are not well achieved for clinical uses. It remains to be a challenging task due to its tight attachment to the lung wall, inhomogeneous background noises and large variations in sizes and shape. In this paper, we employ Halton low-discrepancy sequences to calculate the volume of the lung lesions. The proposed method directly compute the volume without the procedure of three-dimension (3D) model reconstruction and surface triangulation, which significantly improves the efficiency and reduces the complexity. The main steps of the proposed method are: (1) generate a certain number of random points in each slice using Halton low-discrepancy sequences and calculate the lesion area of each slice through the proportion; (2) obtain the volume by integrating the areas in the sagittal direction. In order to evaluate our proposed method, the experiments were conducted on the sufficient data sets with different size of lung lesions. With the uniform distribution of random points, our proposed method achieves more accurate results compared with other methods, which demonstrates the robustness and accuracy for the volume calculation of CT lung lesions. In addition, our proposed method is easy to follow and can be extensively applied to other applications, e.g., volume calculation of liver tumor, atrial wall aneurysm, etc.

An evaluation of a partial-walled laminar-flow operating room

PubMed Central

Whyte, W.; Shaw, B. H.; Freeman, M. A. R.

1974-01-01

This paper contains an assessment of the physical performance of a permanently installed down-flow laminar-flow operating room at the London Hospital. This system employs partial walls extending 0·76 m (2·5 ft.) from the ceiling, from which the air is allowed to issue freely downwards at an initial velocity of about 0·4 m./sec. (80 ft./min.). The usefulness of the partial wall, as compared with a free issuing system, was demonstrated and a comparison made with a fully walled system. It was shown that a fully walled system would be more efficient than a partial-walled system as there was a loss in air velocity of about 20-25% with the partial wall due to the nonconstrained flow of air. This loss would be reflected in an increase in airborne bacterial count and would mean that an increase of 20-25% in the air volume would be required to obtain the same conditions as with the full-walled system. Entrainment of contaminated air was demonstrated but it was concluded that this would be of little consequence in the centre of the clean area, i.e. at the wound site. Sterile instruments, etc., however, on the outside of the clean area, would be more liable to airborne contamination. Bacterial and dust airborne counts taken during total hip operations gave a very low average figure (0·3 bacteria/ft.3 or 10·5/m.3) from which we conclude that the system was about 30 times cleaner in terms of airborne bacteria than a well ventilated conventional operating-room. We concluded that although the partial-walled system was slightly less efficacious than a normal full-walled system, the freedom of movement and of communication for the operating team could in some circumstances outweigh this disadvantage. Sound levels were such that normal conversation was possible with little or no awareness of background noise. ImagesFig. 2Fig. 3Plate 2Plate 2Plate 3Plate 3Plate 1 PMID:4529595

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.

Managing Leaf Area for Maximum Volume Production in a Loblolly Pine Plantation

Treesearch

Shufang Yu; Quang V. Cao; Jim L. Chambers; Zhenmin Tang; James D. Haywood

1999-01-01

To manage loblolly pine (Pinus taeda L.) stands for maximum volume growth, the relationships between volume growth and leaf area at the tree and stand level under different cultural practices (thinning and fertilization) were examined. Forty-eight trees were harvested in 1995, six years after treatment, for individual tree measurements, and 336...

Calculus Students' Understanding of Area and Volume Units

ERIC Educational Resources Information Center

Dorko, Allison; Speer, Natasha

2015-01-01

Units of measure are critical in many scientific fields. While instructors often note that students struggle with units, little research has been conducted about the nature and extent of these difficulties or why they exist. We investigated calculus students' unit use in area and volume computations. Seventy-three percent of students gave…

Breathing pattern and chest wall volumes during exercise in patients with cystic fibrosis, pulmonary fibrosis and COPD before and after lung transplantation.

PubMed

Wilkens, H; Weingard, B; Lo Mauro, A; Schena, E; Pedotti, A; Sybrecht, G W; Aliverti, A

2010-09-01

Pulmonary fibrosis (PF), cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) often cause chronic respiratory failure (CRF). In order to investigate if there are different patterns of adaptation of the ventilatory pump in CRF, in three groups of lung transplant candidates with PF (n=9, forced expiratory volume in 1 s (FEV(1))=37+/-3% predicted, forced vital capacity (FVC)=32+/-2% predicted), CF (n=9, FEV(1)=22+/-3% predicted, FVC=30+/-3% predicted) and COPD (n=21, FEV(1)=21+/-1% predicted, FVC=46+/-2% predicted), 10 healthy controls and 16 transplanted patients, total and compartmental chest wall volumes were measured by opto-electronic plethysmography during rest and exercise. Three different breathing patterns were found during CRF in PF, CF and COPD. Patients with COPD were characterised by a reduced duty cycle at rest and maximal exercise (34+/-1%, p<0.001), while patients with PF and CF showed an increased breathing frequency (49+/-6 and 34+/-2/min, respectively) and decreased tidal volume (0.75+/-0.10 and 0.79+/-0.07 litres) (p<0.05). During exercise, end-expiratory chest wall and rib cage volumes increased significantly in patients with COPD and CF but not in those with PF. End-inspiratory volumes did not increase in CF and PF. The breathing pattern of transplanted patients was similar to that of healthy controls. There are three distinct patterns of CRF in patients with PF, CF and COPD adopted by the ventilatory pump to cope with the underlying lung disease that may explain why patients with PF and CF are prone to respiratory failure earlier than patients with COPD. After lung transplantation the chronic adaptations of the ventilatory pattern to advanced lung diseases are reversible and indicate that the main contributing factor is the lung itself rather than systemic effects of the disease.

Automatic lumen and outer wall segmentation of the carotid artery using deformable three-dimensional models in MR angiography and vessel wall images.

PubMed

van 't Klooster, Ronald; de Koning, Patrick J H; Dehnavi, Reza Alizadeh; Tamsma, Jouke T; de Roos, Albert; Reiber, Johan H C; van der Geest, Rob J

2012-01-01

To develop and validate an automated segmentation technique for the detection of the lumen and outer wall boundaries in MR vessel wall studies of the common carotid artery. A new segmentation method was developed using a three-dimensional (3D) deformable vessel model requiring only one single user interaction by combining 3D MR angiography (MRA) and 2D vessel wall images. This vessel model is a 3D cylindrical Non-Uniform Rational B-Spline (NURBS) surface which can be deformed to fit the underlying image data. Image data of 45 subjects was used to validate the method by comparing manual and automatic segmentations. Vessel wall thickness and volume measurements obtained by both methods were compared. Substantial agreement was observed between manual and automatic segmentation; over 85% of the vessel wall contours were segmented successfully. The interclass correlation was 0.690 for the vessel wall thickness and 0.793 for the vessel wall volume. Compared with manual image analysis, the automated method demonstrated improved interobserver agreement and inter-scan reproducibility. Additionally, the proposed automated image analysis approach was substantially faster. This new automated method can reduce analysis time and enhance reproducibility of the quantification of vessel wall dimensions in clinical studies. Copyright © 2011 Wiley Periodicals, Inc.

Hypothalamic tumors impact gray and white matter volumes in fronto-limbic brain areas.

PubMed

Özyurt, Jale; Müller, Hermann L; Warmuth-Metz, Monika; Thiel, Christiane M

2017-04-01

Patients with hypothalamic involvement of a sellar/parasellar tumor often suffer from cognitive and social-emotional deficits that a lesion in the hypothalamus cannot fully explain. It is conceivable that these deficits are partly due to distal changes in hypothalamic networks, evolving secondary to a focal lesion. Focusing on childhood-onset craniopharyngioma patients, we aimed at investigating the impact of hypothalamic lesions on gray and white matter areas densely connected to the hypothalamus, and to relate structural changes to neuropsychological deficits frequently observed in patients. We performed a voxel-based morphometric analysis based on data of 11 childhood-onset craniopharyngioma patients with hypothalamic tumor involvement, and 18 healthy controls (median age: 17.2 and 17.4 yrs.). Whole-brain analyses were used to test for volumetric differences between the groups (T-tests) and subsequent regression analyses were used to correlate neuropsychological performance with gray and white matter volumes within the patient group. Patients compared to controls had significantly reduced gray matter volumes in areas of the anterior and posterior limbic subsystems which are densely connected with the hypothalamus. In addition, a reduction in white matter volumes was observed in tracts connecting the hypothalamus to other limbic areas. Worse long-term memory retrieval was correlated with smaller gray matter volumes in the posterior cingulate cortex. Our data provide the first evidence that hypothalamic tumor involvement impacts gray and white matter volumes in limbic areas, outside the area of tumor growth. Notably, the functional range of the two limbic subsystems affected, strikingly parallels the two major domains of psychological complaints in patients i.e., deficits in episodic memory and in socio-emotional functioning. We suggest that focal hypothalamic lesions may trigger distal changes in connected brain areas, which then contribute to the impairments in

Effect of degassing temperature on specific surface area and pore volume measurements of biochar

NASA Astrophysics Data System (ADS)

Sigmund, Gabriel; Hüffer, Thorsten; Kah, Melanie; Hofmann, Thilo

2017-04-01

Specific surface area, pore volume, and pore size distribution are key biochar properties that have been related to water and nutrient cycling, microbial activity as well as sorption potential for organic compounds. Specific surface area and pore volume are commonly determined by measurement of physisorption of N2 and/or CO2. The measurement requires prior degassing of the samples, which may change the structure of the materials. Information on degassing temperature is rarely reported in literature, and recommendations differ considerably between existing guidelines for biochar characterization. Therefore, the influence of degassing temperature on N2 and CO2physisorption measurements was investigated by systematically degassing a range of materials, including four biochars, Al2O3 and carbon nanotubes at different temperatures (105 ˚ C, 150 ˚ C, 200 ˚ C, 250 ˚ C and 300 ˚ C for ≥ 14 h each). Measured specific surface area and pore volume increased with increasing degassing temperature for all biochars. Additional surface area and pore volume may have become available as components in biochars volatilized during the degassing phase. The results of our study showed that (i) degassing conditions change material properties, and influence physisorption measurements for biochar (ii) comparison between parameters derived from different degassing protocols may not be appropriate, and (iii) degassing protocols should be harmonized in the biochar community [1]. [1] Sigmund, et al. (2016), "Biochar total surface area and total pore volume determined by N2 and CO2 physisorption are strongly influenced by degassing temperature", STOTEN, doi: http://dx.doi.org/10.1016/j.scitotenv.2016.12.023.

Numerical simulation of the effect of groundwater salinity on artificial freezing wall in coastal area

NASA Astrophysics Data System (ADS)

Hu, Rui; Liu, Quan

2017-04-01

During the engineering projects with artificial ground freezing (AFG) techniques in coastal area, the freezing effect is affected by groundwater salinity. Based on the theories of artificially frozen soil and heat transfer in porous material, and with the assumption that only the variations of total dissolved solids (TDS) impact on freezing point and thermal conductivity, a numerical model of an AFG project in a saline aquifer was established and validated by comparing the simulated temperature field with the calculated temperature based on the analytic solution of rupak (reference) for single-pipe freezing temperature field T. The formation and development of freezing wall were simulated with various TDS. The results showed that the variety of TDS caused the larger temperature difference near the frozen front. With increasing TDS in the saline aquifer (1 35g/L), the average thickness of freezing wall decreased linearly and the total formation time of the freezing wall increased linearly. Compared with of the scenario of fresh-water (<1g/L), the average thickness of frozen wall decreased by 6% and the total formation time of the freezing wall increased by 8% with each increasing TDS of 7g/L. Key words: total dissolved solids, freezing point, thermal conductivity, freezing wall, numerical simulation Reference D.J.Pringel, H.Eicken, H.J.Trodahl, etc. Thermal conductivity of landfast Antarctic and Arctic sea ice[J]. Journal of Geophysical Research, 2007, 112: 1-13. Lukas U.Arenson, Dave C.Sego. The effect of salinity on the freezing of coarse- grained sand[J]. Canadian Geotechnical Journal, 2006, 43: 325-337. Hui Bing, Wei Ma. Laboratory investigation of the freezing point of saline soil[J]. Cold Regions Science and Technology, 2011, 67: 79-88.

Experimental determination of the PTW 60019 microDiamond dosimeter active area and volume

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

Marinelli, Marco, E-mail: marco.marinelli@uniroma2

Purpose: Small field output correction factors have been studied by several research groups for the PTW 60019 microDiamond (MD) dosimeter, by comparing the response of such a device with both reference dosimeters and Monte Carlo simulations. A general good agreement is observed for field sizes down to about 1 cm. However, evident inconsistencies can be noticed when comparing some experimental results and Monte Carlo simulations obtained for smaller irradiation fields. This issue was tentatively attributed by some authors to unintentional large variations of the MD active surface area. The aim of the present study is a nondestructive experimental determination ofmore » the MD active surface area and active volume. Methods: Ten MD dosimeters, one MD prototype, and three synthetic diamond samples were investigated in the present work. 2D maps of the MD response were recorded under scanned soft x-ray microbeam irradiation, leading to an experimental determination of the device active surface area. Profiles of the device responses were measured as well. In order to evaluate the MD active volume, the thickness of the diamond sensing layer was independently evaluated by capacitance measurements and alpha particle detection experiments. The MD sensitivity, measured at the PTW calibration laboratory, was also used to calculate the device active volume thickness. Results: An average active surface area diameter of (2.19 ± 0.02) mm was evaluated by 2D maps and response profiles of all the MDs. Average active volume thicknesses of (1.01 ± 0.13) μm and (0.97 ± 0.14) μm were derived by capacitance and sensitivity measurements, respectively. The obtained results are well in agreement with the nominal values reported in the manufacturer dosimeter specifications. A homogeneous response was observed over the whole device active area. Besides the one from the device active volume, no contributions from other components of the housing nor from encapsulation materials were

Effect of Yeast Cell Morphology, Cell Wall Physical Structure and Chemical Composition on Patulin Adsorption.

PubMed

Luo, Ying; Wang, Jianguo; Liu, Bin; Wang, Zhouli; Yuan, Yahong; Yue, Tianli

2015-01-01

The capability of yeast to adsorb patulin in fruit juice can aid in substantially reducing the patulin toxic effect on human health. This study aimed to investigate the capability of yeast cell morphology and cell wall internal structure and composition to adsorb patulin. To compare different yeast cell morphologies, cell wall internal structure and composition, scanning electron microscope, transmission electron microscope and ion chromatography were used. The results indicated that patulin adsorption capability of yeast was influenced by cell surface areas, volume, and cell wall thickness, as well as 1,3-β-glucan content. Among these factors, cell wall thickness and 1,3-β-glucan content serve significant functions. The investigation revealed that patulin adsorption capability was mainly affected by the three-dimensional network structure of the cell wall composed of 1,3-β-glucan. Finally, patulin adsorption in commercial kiwi fruit juice was investigated, and the results indicated that yeast cells could adsorb patulin from commercial kiwi fruit juice efficiently. This study can potentially simulate in vitro cell walls to enhance patulin adsorption capability and successfully apply to fruit juice industry.

Effect of finishing instrumentation using NiTi hand files on volume, surface area and uninstrumented surfaces in C-shaped root canal systems.

PubMed

Amoroso-Silva, P; Alcalde, M P; Hungaro Duarte, M A; De-Deus, G; Ordinola-Zapata, R; Freire, L G; Cavenago, B C; De Moraes, I G

2017-06-01

To assess the effect of 90°-oscillatory instrumentation with hand files on several morphological parameters (volume, surface area and uninstrumented surface) in C-shaped root canals after instrumentation using a single-file reciprocation system (Reciproc; VDW, Munich, Germany) and a Self-Adjusting File System (SAF; ReDent Nova, Ra'anana, Israel). Twenty mandibular second molars with C-shaped canals and C1 canal configurations were divided into two groups (n = 10) and instrumented with Reciproc and SAF instruments. A size 30 NiTi hand K-file attached to a 90°-oscillatory motion handpiece was used as final instrumentation in both groups. The specimens were scanned using micro-computed tomography after all procedures. Volume, surface area increase and uninstrumented root canal surface were analysed using CTAn software (Bruker-microCT, Kontich, Belgium). Also, the uninstrumented root canal surface was calculated for each canal third. All values were compared between groups using the Mann-Whitney test and within groups using the Wilcoxon's signed-rank test. Instrumentation with Reciproc significantly increased canal volume compared with instrumentation with SAF. Additionally, the canal volumes were significantly increased after 90°-oscillatory instrumentation (between and within group comparison; (P < 0.05)). Regarding the increase in surface area after all instrumentation protocols, statistical analysis only revealed significant differences in the within groups comparison (P < 0.05). Reciproc and SAF instrumentation yielded an uninstrumented root canal surface of 28% and 34%, respectively, which was not significantly different (P > 0.05). Final oscillatory instrumentation significantly reduced the uninstrumented root canal surface from 28% to 9% (Reciproc) and from 34% to 15% (SAF; P < 0.05). The apical and middle thirds exhibited larger uninstrumented root canal surfaces after the first instrumentation that was significantly reduced after oscillatory

Economics of abdominal wall reconstruction.

PubMed

Bower, Curtis; Roth, J Scott

2013-10-01

The economic aspects of abdominal wall reconstruction are frequently overlooked, although understandings of the financial implications are essential in providing cost-efficient health care. Ventral hernia repairs are frequently performed surgical procedures with significant economic ramifications for employers, insurers, providers, and patients because of the volume of procedures, complication rates, the significant rate of recurrence, and escalating costs. Because biological mesh materials add significant expense to the costs of treating complex abdominal wall hernias, the role of such costly materials needs to be better defined to ensure the most cost-efficient and effective treatments for ventral abdominal wall hernias. Copyright © 2013 Elsevier Inc. All rights reserved.

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...

Near-wall serpentine cooled turbine airfoil

DOEpatents

Lee, Ching-Pang

2013-09-17

A serpentine coolant flow path (54A-54G) formed by inner walls (50, 52) in a cavity (49) between pressure and suction side walls (22, 24) of a turbine airfoil (20A). A coolant flow (58) enters (56) an end of the airfoil, flows into a span-wise channel (54A), then flows forward (54B) over the inner surface of the pressure side wall, then turns behind the leading edge (26), and flows back along a forward part of the suction side wall, then follows a loop (54E) forward and back around an inner wall (52), then flows along an intermediate part of the suction side wall, then flows into an aft channel (54G) between the pressure and suction side walls, then exits the trailing edge (28). This provides cooling matched to the heating topography of the airfoil, minimizes differential thermal expansion, revives the coolant, and minimizes the flow volume needed.

Is the great attractor really a great wall

NASA Technical Reports Server (NTRS)

Stebbins, Albert; Turner, Michael S.

1988-01-01

Some of the cosmological consequences are discussed of a late time phase transition which produces light domain walls. The observed peculiar velocity field of the Universe and the observed isotropy of the microwave background radiation severely constrain the wall surface density in such a scenario. The most interesting consequence of such a phase transition is the possibility that the local, coherent streaming motion reported by the Seven Samurai could be explained by the repulsive effect of a relic domain wall with the Hubble volume (the Great Wall).

The impact of surface area, volume, curvature, and Lennard-Jones potential to solvation modeling.

PubMed

Nguyen, Duc D; Wei, Guo-Wei

2017-01-05

This article explores the impact of surface area, volume, curvature, and Lennard-Jones (LJ) potential on solvation free energy predictions. Rigidity surfaces are utilized to generate robust analytical expressions for maximum, minimum, mean, and Gaussian curvatures of solvent-solute interfaces, and define a generalized Poisson-Boltzmann (GPB) equation with a smooth dielectric profile. Extensive correlation analysis is performed to examine the linear dependence of surface area, surface enclosed volume, maximum curvature, minimum curvature, mean curvature, and Gaussian curvature for solvation modeling. It is found that surface area and surfaces enclosed volumes are highly correlated to each other's, and poorly correlated to various curvatures for six test sets of molecules. Different curvatures are weakly correlated to each other for six test sets of molecules, but are strongly correlated to each other within each test set of molecules. Based on correlation analysis, we construct twenty six nontrivial nonpolar solvation models. Our numerical results reveal that the LJ potential plays a vital role in nonpolar solvation modeling, especially for molecules involving strong van der Waals interactions. It is found that curvatures are at least as important as surface area or surface enclosed volume in nonpolar solvation modeling. In conjugation with the GPB model, various curvature-based nonpolar solvation models are shown to offer some of the best solvation free energy predictions for a wide range of test sets. For example, root mean square errors from a model constituting surface area, volume, mean curvature, and LJ potential are less than 0.42 kcal/mol for all test sets. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Ultimate Cost of Building Walls.

ERIC Educational Resources Information Center

Grimm, Clayford T.; Gross, James G.

The need for economic analysis of building walls is discussed, and the factors influencing the ultimate cost of exterior walls are studied. The present worth method is used to analyze three types of exterior non-loadbearing panel or curtain walls. Anticipated costs are expressed in terms of their present value per square foot of wall area. The…

Morphological abnormalities in prefrontal surface area and thalamic volume in attention deficit/hyperactivity disorder.

PubMed

Batty, Martin J; Palaniyappan, Lena; Scerif, Gaia; Groom, Madeleine J; Liddle, Elizabeth B; Liddle, Peter F; Hollis, Chris

2015-08-30

Although previous morphological studies have demonstrated abnormalities in prefrontal cortical thickness in children with attention deficit/hyperactivity disorder (ADHD), studies investigating cortical surface area are lacking. As the development of cortical surface is closely linked to the establishment of thalam-ocortical connections, any abnormalities in the structure of the thalamus are likely to relate to altered cortical surface area. Using a clinically well-defined sample of children with ADHD (n = 25, 1 female) and typically developing controls (n = 24, 1 female), we studied surface area across the cortex to determine whether children with ADHD had reduced thalamic volume that related to prefrontal cortical surface area. Relative to controls, children with ADHD had a significant reduction in thalamic volume and dorsolateral prefrontal cortical area in both hemispheres. Furthermore, children with ADHD with smaller thalamic volumes were found to have greater reductions in surface area, a pattern not evident in the control children. Our results are further evidence of reduced lateral prefrontal cortical area in ADHD. Moreover, for the first time, we have also shown a direct association between thalamic anatomy and frontal anatomy in ADHD, suggesting the pathophysiological process that alters surface area maturation is likely to be linked to the development of the thalamus. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Calculation of area and volume for the south part of Great Salt Lake, Utah

USGS Publications Warehouse

Baskin, Robert L.

2005-01-01

The U.S. Geological Survey, in cooperation with the Utah Department of Natural Resources, Division of Wildlife Resources, collected bathymetric data for the south part of Great Salt Lake during 2002-04 using a single-beam, high-definition fathometer and real-time differential global positioning system. About 7.6 million depth measurements were collected along more than 930 miles (1,690 kilometers) of survey transects. Sound-velocity profiles were obtained in conjunction with the bathymetric data to provide time-of-travel corrections to the depth calculations. Data were processed with commercial hydrographic software and exported into geographic information system (GIS) software for mapping and calculation of area and volume. Area and volume calculations show a maximum area of about 508,000 acres (2,056 square kilometers) and a maximum volume of about 9,257,000 acre-feet (11.42 cubic kilometers) at a water-surface altitude of 4,200 feet (1,280 meters). Minimum water-surface altitude of the south part of Great Salt Lake is just below 4,167 feet (1,279 meters) in the area just south of the Union Pacific railroad causeway halfway between Promontory Point and the western edge of the lake. At this altitude, and continuing up to about 4,176 feet (1,279 meters), the south part of the lake is separated into two areas by a ridge extending from Promontory Point to Hat Island. Calculations for area and volume are based on a low altitude of 4,167 feet (1,279 meters) to a high altitude of 4,200 feet (1,280 meters).

Remedial Investigation Report Area of Contamination (AOC) 43G. Volume 1

DTIC Science & Technology

1996-02-01

FORT DEVENS FINAL REMEDIAL INVESTIGATION FOR GROUP 2 & 7 SITES FINAL REMEDIAL INVESTIGATION REPORT AREA OF CONTAMINATION ( AOC ) 43G VOLUME I OF II...Liability Act for environmental investigations and remedial actions at Fort Devens . The agreement required that Site Investigations be undertaken at each... Remedial Investigation (RI) Report on Area of Contamination ( AOC ) 43G at the Fort Devens U.S. Army Installation, Massachusetts (

North wall, central part, showing partial partition wall at left. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

North wall, central part, showing partial partition wall at left. This area is labeled “Pioneering Research” on drawing copy NV-35-B-5 (submitted with HABS No. NV-35-B) (series 2 of 4) - Bureau of Mines Metallurgical Research Laboratory, Original Building, Date Street north of U.S. Highway 93, Boulder City, Clark County, NV

Brain development during adolescence: A mixed-longitudinal investigation of cortical thickness, surface area, and volume.

PubMed

Vijayakumar, Nandita; Allen, Nicholas B; Youssef, George; Dennison, Meg; Yücel, Murat; Simmons, Julian G; Whittle, Sarah

2016-06-01

What we know about cortical development during adolescence largely stems from analyses of cross-sectional or cohort-sequential samples, with few studies investigating brain development using a longitudinal design. Further, cortical volume is a product of two evolutionarily and genetically distinct features of the cortex - thickness and surface area, and few studies have investigated development of these three characteristics within the same sample. The current study examined maturation of cortical thickness, surface area and volume during adolescence, as well as sex differences in development, using a mixed longitudinal design. 192 MRI scans were obtained from 90 healthy (i.e., free from lifetime psychopathology) adolescents (11-20 years) at three time points (with different MRI scanners used at time 1 compared to 2 and 3). Developmental trajectories were estimated using linear mixed models. Non-linear increases were present across most of the cortex for surface area. In comparison, thickness and volume were both characterised by a combination of non-linear decreasing and increasing trajectories. While sex differences in volume and surface area were observed across time, no differences in thickness were identified. Furthermore, few regions exhibited sex differences in the cortical development. Our findings clearly illustrate that volume is a product of surface area and thickness, with each exhibiting differential patterns of development during adolescence, particularly in regions known to contribute to the development of social-cognition and behavioral regulation. These findings suggest that thickness and surface area may be driven by different underlying mechanisms, with each measure potentially providing independent information about brain development. Hum Brain Mapp 37:2027-2038, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Minerals Yearbook, volume III, Area Reports—International—Asia and the Pacific

USGS Publications Warehouse

Geological Survey, U.S.

2018-01-01

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included.Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals.Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section.The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

Minerals Yearbook, volume III, Area Reports—International—Latin America and Canada

USGS Publications Warehouse

,

2018-01-01

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included.Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals.Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section.The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

Minerals Yearbook, volume III, Area Reports—International—Europe and Central Eurasia

USGS Publications Warehouse

Geological Survey, U.S.

2018-01-01

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included.Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals.Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section.The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

Contribution of CT quantified emphysema, air trapping and airway wall thickness on pulmonary function in male smokers with and without COPD.

PubMed

Mohamed Hoesein, Firdaus A A; de Jong, Pim A; Lammers, Jan-Willem J; Mali, Willem P Th M; Mets, Onno M; Schmidt, Michael; de Koning, Harry J; Aalst, Carlijn van der; Oudkerk, Matthijs; Vliegenthart, Rozemarijn; Ginneken, Bram van; van Rikxoort, Eva M; Zanen, Pieter

2014-09-01

Emphysema, airway wall thickening and air trapping are associated with chronic obstructive pulmonary disease (COPD). All three can be quantified by computed tomography (CT) of the chest. The goal of the current study is to determine the relative contribution of CT derived parameters on spirometry, lung volume and lung diffusion testing. Emphysema, airway wall thickening and air trapping were quantified automatically on CT in 1,138 male smokers with and without COPD. Emphysema was quantified by the percentage of voxels below -950 Hounsfield Units (HU), airway wall thickness by the square root of wall area for a theoretical airway with 10 mm lumen perimeter (Pi10) and air trapping by the ratio of mean lung density at expiration and inspiration (E/I-ratio). Spirometry, residual volume to total lung capacity (RV/TLC) and diffusion capacity (Kco) were obtained. Standardized regression coefficients (β) were used to analyze the relative contribution of CT changes to pulmonary function measures. The independent contribution of the three CT measures differed per lung function parameter. For the FEV1 airway wall thickness was the most contributing structural lung change (β = -0.46), while for the FEV1/FVC this was emphysema (β = -0.55). For the residual volume (RV) air trapping was most contributing (β = -0.35). Lung diffusion capacity was most influenced by emphysema (β = -0.42). In a cohort of smokers with and without COPD the effect of different CT changes varies per lung function measure and therefore emphysema, airway wall thickness and air trapping need to be taken in account.

Mass-independent area (or entropy) and thermodynamic volume products in conformal gravity

NASA Astrophysics Data System (ADS)

Pradhan, Parthapratim

2017-06-01

In this work, we investigate the thermodynamic properties of conformal gravity in four dimensions. We compute the area (or entropy) functional relation for this black hole (BH). We consider both de Sitter (dS) and anti-de Sitter (AdS) cases. We derive the Cosmic-Censorship-Inequality which is an important relation in general relativity that relates the total mass of a spacetime to the area of all the BH horizons. Local thermodynamic stability is studied by computing the specific heat. The second-order phase transition occurs at a certain condition. Various types of second-order phase structure have been given for various values of a and the cosmological constant Λ in the Appendix. When a = 0, one obtains the result of Schwarzschild-dS and Schwarzschild-AdS cases. In the limit aM ≪ 1, one obtains the result of Grumiller spacetime, where a is nontrivial Rindler parameter or Rindler acceleration and M is the mass parameter. The thermodynamic volume functional relation is derived in the extended phase space, where the cosmological constant is treated as a thermodynamic pressure and its conjugate variable as a thermodynamic volume. The mass-independent area (or entropy) functional relation and thermodynamic volume functional relation that we have derived could turn out to be a universal quantity.

Comparison of Mammographic Density Assessed as Volumes and Areas among Women Undergoing Diagnostic Image-Guided Breast Biopsy

PubMed Central

Gierach, Gretchen L.; Geller, Berta M.; Shepherd, John A.; Patel, Deesha A.; Vacek, Pamela M.; Weaver, Donald L.; Chicoine, Rachael E.; Pfeiffer, Ruth M.; Fan, Bo; Mahmoudzadeh, Amir Pasha; Wang, Jeff; Johnson, Jason M.; Herschorn, Sally D.; Brinton, Louise A.; Sherman, Mark E.

2014-01-01

Background Mammographic density (MD), the area of non-fatty appearing tissue divided by total breast area, is a strong breast cancer risk factor. Most MD analyses have employed visual categorizations or computer-assisted quantification, which ignore breast thickness. We explored MD volume and area, using a volumetric approach previously validated as predictive of breast cancer risk, in relation to risk factors among women undergoing breast biopsy. Methods Among 413 primarily white women, ages 40–65, undergoing diagnostic breast biopsies between 2007–2010 at an academic facility in Vermont, MD volume (cm3) was quantified in cranio-caudal views of the breast contralateral to the biopsy target using a density phantom, while MD area (cm2) was measured on the same digital mammograms using thresholding software. Risk factor associations with continuous MD measurements were evaluated using linear regression. Results Percent MD volume and area were correlated (r=0.81) and strongly and inversely associated with age, body mass index (BMI), and menopause. Both measures were inversely associated with smoking and positively associated with breast biopsy history. Absolute MD measures were correlated (r=0.46) and inversely related to age and menopause. Whereas absolute dense area was inversely associated with BMI, absolute dense volume was positively associated. Conclusions Volume and area MD measures exhibit some overlap in risk factor associations, but divergence as well, particularly for BMI. Impact Findings suggest that volume and area density measures differ in subsets of women; notably, among obese women, absolute density was higher with volumetric methods, suggesting that breast cancer risk assessments may vary for these techniques. PMID:25139935

Field evaluation of support practice (P-factor) for stone walls to control soil erosion in an arid area (Northern Jordan)

NASA Astrophysics Data System (ADS)

Gharaibeh, Mamoun; Albalasmeh, Ammar

2017-04-01

Stone walls have been adopted for long time to control water erosion in many Mediterranean countries. In soil erosion equations, the support practice factor (P-factor) for stone walls has not been fully studied or rarely taken into account especially in semi-arid and arid regions. Field studies were conducted to evaluate the efficiency of traditional stone walls and to quantify soil erosion in six sites in north and northeastern Jordan. Initial estimates using the Universal Soil Loss Equation (USLE) showed that rainfall erosion was reduced by 65% in areas where stone walls are present. Annual soil loss ranged from 5 to 15 t yr-1. The mean annual soil loss in the absence of stone walls ranged from 10-60 t ha-1 with an average value of 35 t ha-1. Interpolating the slope of thickness of A horizon provided an average initial estimate of 0.3 for P value.

Calculation of area and volume for the north part of Great Salt Lake, Utah

USGS Publications Warehouse

Baskin, Robert L.

2006-01-01

The U.S. Geological Survey, in cooperation with the Utah Department of Natural Resources, Division of Forestry, Fire, and State Lands, collected bathymetric data for the north part of Great Salt Lake during the spring and early summer of 2006 using a single-beam, high-definition fathometer and real-time differential global positioning system. About 5.2 million depth measurements were collected along more than 765 miles (1,230 kilometers) of survey transects. Sound-velocity profiles were obtained in conjunction with the bathymetric data to provide time-of-travel corrections to the depth calculations. Data were processed with commercial hydrographic software and exported into geographic information system (GIS) software for mapping and calculation of area and volume. Area and volume calculations show a maximum area of about 385,000 acres (1,560 square kilometers) and a maximum volume of about 5,693,000 acre-feet (about 7 cubic kilometers) at a water-surface altitude of 4,200 feet (1,280 meters). Minimum natural water-surface altitude of the north part of Great Salt Lake is just below 4,167 feet (1,270 meters) in the area just north of the Union Pacific railroad causeway halfway between Saline and the western edge of the lake. The north part of Great Salt Lake generally grades gradually to the west and north and is bounded by steep scarps along its eastern border. Calculations for area and volume are based on a low altitude of 4,167 feet (1,270 meters) to a high altitude of 4,200 feet (1,280 meters).

Rain volume estimation over areas using satellite and radar data

NASA Technical Reports Server (NTRS)

Doneaud, Andre A.; Vonderhaar, T. H.; Johnson, L. R.; Laybe, P.; Reinke, D.

1987-01-01

The analysis of 18 convective clusters demonstrates that the extension of the Area-Time-Integral (ATI) technique to the use of satellite data is possible. The differences of the internal structures of the radar reflectivity features, and of the satellite features, give rise to differences in estimating rain volumes by delineating area; however, by focusing upon the area integrated over the lifetime of the storm, it is suggested that some of the errors produced by the differences in the cloud geometries as viewed by radar or satellite are minimized. The results are good and future developments should consider data from different climatic regions and should allow for implementation of the technique in a general circulation model.

Effect of Yeast Cell Morphology, Cell Wall Physical Structure and Chemical Composition on Patulin Adsorption

PubMed Central

Luo, Ying; Wang, Jianguo; Liu, Bin; Wang, Zhouli; Yuan, Yahong; Yue, Tianli

2015-01-01

The capability of yeast to adsorb patulin in fruit juice can aid in substantially reducing the patulin toxic effect on human health. This study aimed to investigate the capability of yeast cell morphology and cell wall internal structure and composition to adsorb patulin. To compare different yeast cell morphologies, cell wall internal structure and composition, scanning electron microscope, transmission electron microscope and ion chromatography were used. The results indicated that patulin adsorption capability of yeast was influenced by cell surface areas, volume, and cell wall thickness, as well as 1,3-β-glucan content. Among these factors, cell wall thickness and 1,3-β-glucan content serve significant functions. The investigation revealed that patulin adsorption capability was mainly affected by the three-dimensional network structure of the cell wall composed of 1,3-β-glucan. Finally, patulin adsorption in commercial kiwi fruit juice was investigated, and the results indicated that yeast cells could adsorb patulin from commercial kiwi fruit juice efficiently. This study can potentially simulate in vitro cell walls to enhance patulin adsorption capability and successfully apply to fruit juice industry. PMID:26295574

Turbine airfoil having near-wall cooling insert

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

Martin, Jr., Nicholas F.; Wiebe, David J.

A turbine airfoil is provided with at least one insert positioned in a cavity in an airfoil interior. The insert extends along a span-wise extent of the turbine airfoil and includes first and second opposite faces. A first near-wall cooling channel is defined between the first face and a pressure sidewall of an airfoil outer wall. A second near-wall cooling channel is defined between the second face and a suction sidewall of the airfoil outer wall. The insert is configured to occupy an inactive volume in the airfoil interior so as to displace a coolant flow in the cavity towardmore » the first and second near-wall cooling channels. A locating feature engages the insert with the outer wall for supporting the insert in position. The locating feature is configured to control flow of the coolant through the first or second near-wall cooling channel.« less

Rumen morphometrics and the effect of digesta pH and volume on volatile fatty acid absorption.

PubMed

Melo, L Q; Costa, S F; Lopes, F; Guerreiro, M C; Armentano, L E; Pereira, M N

2013-04-01

The effects of rumen digesta volume and pH on VFA absorption and its relation to rumen wall morphology were evaluated. Nine rumen cannulated cows formed 3 groups based on desired variation in rumen morphology: The High group was formed by Holsteins yielding 25.9 kg milk/d and fed on a high-grain total mixed ration (TMR); the Medium group by Holstein-Zebu crossbreds yielding 12.3 kg milk/d and fed on corn silage, tropical pasture, and a commercial concentrate; and the Dry group by nonlactating grazing Jerseys fed exclusively on tropical pasture. Within each group, a sequence of 3 ruminal conditions was induced on each cow in 3 × 3 Latin Squares, with 7-d periods: high digesta volume and high pH (HVHP), low volume and high pH (LVHP), and low volume and low pH (LVLP). Rumen mucosa was biopsied on the first day of Period 1. Ruminal morphometric variables evaluated were mitotic index, absorptive surface and papillae number per square centimeter of wall, area per papillae, papillae area as a percentage of absorptive surface, and epithelium, keratinized layer, and nonkeratinized layer thickness. There was marked variation in rumen morphology among the groups of cows. Grazing Jerseys had decreased rumen wall absorptive surface area and basal cells mitotic index, and increased thickness of the epithelium and of the keratin layer compared with cows receiving concentrates. Mean rumen pH throughout the 4 h sampling period was: 6.78 for HVHP, 7.08 for LVHP, and 5.90 for LVLP (P < 0.01). The capacity of the rumen wall to absorb VFA was estimated by the Valerate/CrEDTA technique. The fractional exponential decay rate for the ratio of valeric acid to Cr (k Val/Cr) was determined by rumen digesta sampling at 20-min intervals during 4 h, after the mixing of markers and the return of the evacuated ruminal content. The k Val/Cr values for treatments HVHP, LVHP, and LVLP were, respectively: 19.6, 23.9, and 35.0 %/h (SEM = 2.01; P = 0.21 for contrast HVHP vs. LVHP and P < 0.01 for

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.

Factors Associated With Chest Wall Toxicity After Accelerated Partial Breast Irradiation Using High-Dose-Rate Brachytherapy

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

Brown, Sheree, E-mail: shereedst32@hotmail.com; Vicini, Frank; Vanapalli, Jyotsna R.

2012-07-01

Purpose: The purpose of this analysis was to evaluate dose-volume relationships associated with a higher probability for developing chest wall toxicity (pain) after accelerated partial breast irradiation (APBI) by using both single-lumen and multilumen brachytherapy. Methods and Materials: Rib dose data were available for 89 patients treated with APBI and were correlated with the development of chest wall/rib pain at any point after treatment. Ribs were contoured on computed tomography planning scans, and rib dose-volume histograms (DVH) along with histograms for other structures were constructed. Rib DVH data for all patients were sampled at all volumes {>=}0.008 cubic centimeter (cc)more » (for maximum dose related to pain) and at volumes of 0.5, 1, 2, and 3 cc for analysis. Rib pain was evaluated at each follow-up visit. Patient responses were marked as yes or no. No attempt was made to grade responses. Eighty-nine responses were available for this analysis. Results: Nineteen patients (21.3%) complained of transient chest wall/rib pain at any point in follow-up. Analysis showed a direct correlation between total dose received and volume of rib irradiated with the probability of developing rib/chest wall pain at any point after follow-up. The median maximum dose at volumes {>=}0.008 cc of rib in patients who experienced chest wall pain was 132% of the prescribed dose versus 95% of the prescribed dose in those patients who did not experience pain (p = 0.0035). Conclusions: Although the incidence of chest wall/rib pain is quite low with APBI brachytherapy, attempts should be made to keep the volume of rib irradiated at a minimum and the maximum dose received by the chest wall as low as reasonably achievable.« less

Increased Airway Wall Thickness is Associated with Adverse Longitudinal First-Second Forced Expiratory Volume Trajectories of Former World Trade Center workers.

PubMed

de la Hoz, Rafael E; Liu, Xiaoyu; Doucette, John T; Reeves, Anthony P; Bienenfeld, Laura A; Wisnivesky, Juan P; Celedón, Juan C; Lynch, David A; San José Estépar, Raúl

2018-05-24

Occupational exposures at the WTC site after September 11, 2001 have been associated with several presumably inflammatory lower airway diseases. In this study, we describe the trajectories of expiratory air flow decline, identify subgroups with adverse progression, and investigate the association of a quantitative computed tomography (QCT) imaging measurement of airway wall thickness, and other risk factors for adverse progression. We examined the trajectories of expiratory air flow decline in a group of 799 former WTC workers and volunteers with QCT-measured (with two independent systems) wall area percent (WAP) and at least 3 periodic spirometries. We calculated individual regression lines for first-second forced expiratory volume (FEV 1 ), identified subjects with rapidly declining and increasing ("gainers"), and compared them to subjects with normal and "stable" FEV 1 decline. We used multivariate logistic regression to model decliner vs. stable trajectories. The mean longitudinal FEV 1 slopes for the entire study population, and its stable, decliner, and gainer subgroups were, respectively, - 35.8, - 8, - 157.6, and + 173.62 ml/year. WAP was associated with "decliner" status (OR adj 1.08, 95% CI 1.02, 1.14, per 5% increment) compared to stable. Age, weight gain, baseline FEV 1 percent predicted, bronchodilator response, and pre-WTC occupational exposures were also significantly associated with accelerated FEV 1 decline. Analyses of gainers vs. stable subgroup showed WAP as a significant predictor in unadjusted but not consistently in adjusted analyses. The apparent normal age-related rate of FEV 1 decline results from averaging widely divergent trajectories. WAP is significantly associated with accelerated air flow decline in WTC workers.

Self-pressurization of a flightweight liquid hydrogen tank: Effects of fill level at low wall heat flux

NASA Technical Reports Server (NTRS)

Vandresar, N. T.; Hasan, M. M.; Lin, C.-S.

1991-01-01

Experimental results are presented for the self pressurization and thermal stratification of a 4.89 cu m liquid hydrogen storage tank subjected to low heat flux (2.0 and 3.5 W/sq m) in normal gravity. The test tank was representative of future spacecraft tankage, having a low mass to volume ratio and high performance multilayer thermal insulation. Tests were performed at fill levels of 29 and 49 pcts. (by volume) and complement previous tests at 83 pct. fill. As the heat flux increases, the pressure rise rate at each fill level exceeds the homogeneous rate by an increasing ratio. Herein, this ratio did not exceed a value of 2. The slowest pressure rise rate was observed for the 49 pct. fill level at both heat fluxes. This result is attributed to the oblate spheroidal tank geometry which introduces the variables of wetted wall area, liquid-vapor interfacial area, and ratio of side wall to bottom heating as a function of fill level or liquid depth. Initial tank thermal conditions were found to affect the initial pressure rise rate. Quasi steady pressure rise rates are independent of starting conditions.

Association of physical activity and physical performance with tibial cartilage volume and bone area in young adults.

PubMed

Antony, Benny; Venn, Alison; Cicuttini, Flavia; March, Lyn; Blizzard, Leigh; Dwyer, Terence; Cross, Marita; Jones, Graeme; Ding, Changhai

2015-10-26

Physical activity has been recommended to patients with knee osteoarthritis for improving their symptoms. However, it is still controversial if physical activity has effects on joint structures including cartilage volume. The aim of this study was to describe the associations between physical activity and performance measured 5 years prior and tibial cartilage volume and bone area in young adults. Subjects broadly representative of the Australian population (n = 328, aged 31-41 years, female 47.3 %) were selected from the Childhood Determinants of Adult Health study. They underwent T1-weighted fat-suppressed magnetic resonance imaging (MRI) scans of their knees. Tibial bone area and cartilage volume were measured from MRI. Physical activity (measured using long international physical activity questionnaire (IPAQ)) and performance measures (long jump, leg muscle strength, physical work capacity (PWC170)) were measured 5 years prior. In multivariable analyses, total physical activity (min/week) (β: 0.30 mm(3), 95 % CI: 0.13,0.47), vigorous (β: 0.54 mm(3), 95 % CI: 0.13,0.94), moderate (β: 0.34 mm(3), 95 % CI: 0.01,0.67), walking (β: 0.40 mm(3), 95 % CI: 0.07,0.72) and IPAQ category (β: 182.9 mm(3), 95 % CI: 51.8,314.0) were positively associated with total tibial cartilage volume but not tibial bone area. PWC170, long jump and leg muscle strength were positively and significantly associated with both total tibial cartilage volume and total tibial bone area; and the associations with tibial cartilage volume decreased in magnitude but remained significant for PWC170 and long jump after further adjustment for tibial bone area. While tibial bone area is affected only by physical performance, total tibial cartilage volume can be influenced by both physical activity and performance in younger adults. The clinical significance suggests a beneficial effect for cartilage but the bone area association was restricted to performance suggesting other factors

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.

Estimation of bladder wall location in ultrasound images.

PubMed

Topper, A K; Jernigan, M E

1991-05-01

A method of automatically estimating the location of the bladder wall in ultrasound images is proposed. Obtaining this estimate is intended to be the first stage in the development of an automatic bladder volume calculation system. The first step in the bladder wall estimation scheme involves globally processing the images using standard image processing techniques to highlight the bladder wall. Separate processing sequences are required to highlight the anterior bladder wall and the posterior bladder wall. The sequence to highlight the anterior bladder wall involves Gaussian smoothing and second differencing followed by zero-crossing detection. Median filtering followed by thresholding and gradient detection is used to highlight as much of the rest of the bladder wall as was visible in the original images. Then a 'bladder wall follower'--a line follower with rules based on the characteristics of ultrasound imaging and the anatomy involved--is applied to the processed images to estimate the bladder wall location by following the portions of the bladder wall which are highlighted and filling in the missing segments. The results achieved using this scheme are presented.

Lattice Boltzmann simulations for wall-flow dynamics in porous ceramic diesel particulate filters

NASA Astrophysics Data System (ADS)

Lee, Da Young; Lee, Gi Wook; Yoon, Kyu; Chun, Byoungjin; Jung, Hyun Wook

2018-01-01

Flows through porous filter walls of wall-flow diesel particulate filter are investigated using the lattice Boltzmann method (LBM). The microscopic model of the realistic filter wall is represented by randomly overlapped arrays of solid spheres. The LB simulation results are first validated by comparison to those from previous hydrodynamic theories and constitutive models for flows in porous media with simple regular and random solid-wall configurations. We demonstrate that the newly designed randomly overlapped array structures of porous walls allow reliable and accurate simulations for the porous wall-flow dynamics in a wide range of solid volume fractions from 0.01 to about 0.8, which is beyond the maximum random packing limit of 0.625. The permeable performance of porous media is scrutinized by changing the solid volume fraction and particle Reynolds number using Darcy's law and Forchheimer's extension in the laminar flow region.

Efficient gaussian density formulation of volume and surface areas of macromolecules on graphical processing units.

PubMed

Zhang, Baofeng; Kilburg, Denise; Eastman, Peter; Pande, Vijay S; Gallicchio, Emilio

2017-04-15

We present an algorithm to efficiently compute accurate volumes and surface areas of macromolecules on graphical processing unit (GPU) devices using an analytic model which represents atomic volumes by continuous Gaussian densities. The volume of the molecule is expressed by means of the inclusion-exclusion formula, which is based on the summation of overlap integrals among multiple atomic densities. The surface area of the molecule is obtained by differentiation of the molecular volume with respect to atomic radii. The many-body nature of the model makes a port to GPU devices challenging. To our knowledge, this is the first reported full implementation of this model on GPU hardware. To accomplish this, we have used recursive strategies to construct the tree of overlaps and to accumulate volumes and their gradients on the tree data structures so as to minimize memory contention. The algorithm is used in the formulation of a surface area-based non-polar implicit solvent model implemented as an open source plug-in (named GaussVol) for the popular OpenMM library for molecular mechanics modeling. GaussVol is 50 to 100 times faster than our best optimized implementation for the CPUs, achieving speeds in excess of 100 ns/day with 1 fs time-step for protein-sized systems on commodity GPUs. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Stormwater runoff characterized by GIS determined source areas and runoff volumes.

PubMed

Liu, Yang; Soonthornnonda, Puripus; Li, Jin; Christensen, Erik R

2011-02-01

Runoff coefficients are usually considered in isolation for each drainage area with resulting large uncertainties in the areas and coefficients. Accurate areas and coefficients are obtained here by optimizing runoff coefficients for characteristic Geographic Information Systems (GIS) subareas within each drainage area so that the resulting runoff coefficients of each drainage area are consistent with those obtained from runoff and rainfall volumes. Lack of fit can indicate that the ArcGIS information is inaccurate or more likely, that the drainage area needs adjustment. Results for 18 drainage areas in Milwaukee, WI for 2000-2004 indicate runoff coefficients ranging from 0.123 for a mostly residential area to 0.679 for a freeway-related land, with a standard error of 0.047. Optimized runoff coefficients are necessary input parameters for monitoring, and for the analysis and design of in situ stormwater unit operations and processes for the control of both urban runoff quantity and quality.

Minerals Yearbook, volume III, Area Reports—International—Africa and the Middle East

USGS Publications Warehouse

,

2018-01-01

The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included.Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals.Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section.The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

Developing Open-Ended Questions for Surface Area and Volume of Beam

ERIC Educational Resources Information Center

Kurniawan, Henry; Putri, Ratu Ilma Indra; Hartono, Yusuf

2018-01-01

The purpose of this research was to show open-ended questions about surface area and beam volume which valid and practice, have potential effect. This research is research development which consists of two main phases: preliminary phase (preparation phase and problem design) and formative evaluation phase (evaluation and revision phases). The…

27. "TEST STAND; STRUCTURAL; SIDEWALL, NORTH WALL AND SOUTH WALL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

27. "TEST STAND; STRUCTURAL; SIDEWALL, NORTH WALL AND SOUTH WALL FRAMING ELEVATIONS." Specifications No. ENG-04353-55-72; Drawing No. 60-09-12; sheet 27 of 148; file no. 1320/78. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, Rev. B; date: 15 April 1957. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

Association of narrow angles with anterior chamber area and volume measured with anterior-segment optical coherence tomography.

PubMed

Wu, Ren-Yi; Nongpiur, Monisha E; He, Ming-Guang; Sakata, Lisandro M; Friedman, David S; Chan, Yiong-Huak; Lavanya, Raghavan; Wong, Tien-Yin; Aung, Tin

2011-05-01

To describe the measurement of anterior chamber area and anterior chamber volume by anterior-segment optical coherence tomography and to investigate the association of these parameters with the presence of narrow angles. This was a cross-sectional study of subjects aged at least 50 years without ophthalmic symptoms recruited from a community clinic. All participants underwent standardized ocular examination and anterior-segment optical coherence tomography. Customized software was used to measure anterior chamber area (cross-sectional area bounded by the corneal endothelium, anterior surface of iris, and lens within the pupil) and anterior chamber volume (calculated by rotating the anterior chamber area 360° around a vertical axis through the midpoint of the anterior chamber area). An eye was considered to have narrow angles if the posterior pigmented trabecular meshwork was not visible for at least 180° on gonioscopy with the eye in the primary position. A total of 1922 subjects were included in the final analyses, 317 (16.5%) of whom had narrow angles. Mean anterior chamber area (15.6 vs 21.1 mm(2); P < .001) and anterior chamber volume (97.6 vs 142.1 mm(3); P < .001) were smaller in eyes with narrow angles compared with those in eyes without narrow angles. After adjusting for age, sex, anterior chamber depth, axial length, and pupil size, smaller anterior chamber area (odds ratio, 53.2; 95% confidence interval, 27.1-104.5) and anterior chamber volume (odds ratio, 40.2; 95% confidence interval, 21.5-75.2) were significantly associated with the presence of narrow angles. Smaller anterior chamber area and anterior chamber volume were independently associated with narrow angles in Singaporeans, even after controlling for other known ocular risk factors.

'Stucco' Walls

NASA Technical Reports Server (NTRS)

2004-01-01

This projected mosaic image, taken by the microscopic imager, an instrument located on the Mars Exploration Rover Opportunity 's instrument deployment device, or 'arm,' shows the partial clotting or cement-like properties of the sand-sized grains within the trench wall. The area in this image measures approximately 3 centimeters (1.2 inches) wide and 5 centimeters (2 inches) tall.(This image also appears as an inset on a separate image from the rover's navigation camera, showing the location of this particular spot within the trench wall.)

Near Wall measurement in Turbulent Flow over Rough Wall using microscopic HPIV

NASA Astrophysics Data System (ADS)

Talapatra, Siddharth; Hong, Jiarong; Katz, Joseph

2009-11-01

Using holographic PIV, 3D velocity measurements are being performed in a turbulent rough wall channel flow. Our objective is to examine the contribution of coherent structures to the flow dynamics, momentum and energy fluxes in the roughness sublayer. The 0.45mm high, pyramid-shaped roughness is uniformly distributed on the top and bottom surfaces of a 5X20cm rectangular channel flow, where the Reτ is 3400. To facilitate recording of holograms through a rough plate, the working fluid is a concentrated solution of NaI in water, whose optical refractive index is matched with that of the acrylic rough plates. The test section is illuminated by a collimated laser beam from the top, and the sample volume extends from the bottom wall up to 7 roughness heights. After passing through the sample volume, the in-line hologram is magnified and recorded on a 4864X3248 pixels camera at a resolution of 0.74μm/pixel. The flow is locally seeded with 2μm particles. Reconstruction, spatial filtering and particle tracking provide the 3D velocity field. This approach has been successfully implemented recently, as preliminary data demonstrate.

EFFECTOF ISOLATION WALL USING SCRAP TIRE ON GROUND VIBRATION REDUCTION

NASA Astrophysics Data System (ADS)

Kashimoto, Takahiko; Kashimoto, Yusuke; Hayakawa, Kiyoshi; Matsui, Tamotsu; Fujimoto, Hiroaki

Some countermeasure methods against the environmental ground vibration caused by some traffic vibrations have been proposed so far. The authors have developed a new type ground vibration isolation wall using scrap tire, and evaluated its effectiveness on the ground vibration reduction by full scale field tests. In this paper, the authors discussed and examined the effectiveness of the developed countermeasure method by two field tests. The one concerns on the effect of scrap tire as soft material of vibration isolation wall, and the other on the effect of the developed countermeasure method practically applied in a residential area close to monorail traffic. As the results, it was elucidated that the ground vibration of 2-3 dB was reduced in case of two times volume of the soft material, the conversion ratio of the vibration energy of the soft material to the kinetic energy was higher than that of the core material of PHC pile, the vibration acceleration of 0.19 - 1.26 gal was reduced by the developed countermeasure method in case of the monorail traffic, and the vibration reduction measured behind the isolation wall agreed well with the proposed theoretical value, together with confirming the effectiveness of the ground vibration isolation wall using scrap tire as the countermeasure method against the environmental ground vibration.

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.

Summary of Synoptic Meteorological Observations. Indonesian Coastal Marine Areas. Volume 1. Area 1 - Southeast Sumatra. Area 2 - Christmas Island. Area 3 - Sunda Strait. Area 4 - Northwest Java Sea. Area 5 - Bangka Island Northwest. Area 6 - Natuna Island. Area 7 - Sarawak

DTIC Science & Technology

1975-04-01

AD/ A -006 923 SUMMARY OF SYNOPTIC METEOROLOGICAL OBSERVATIONS. INDONESIAN COASTAL MARINE AREAS. VOLUME I. AREA 1 - SOUTHEAST SUMATRA. AREA 2...Weather Service Command Washington, D. C. April 1975 ;V, A DISTRIBUTED BY: Nausm Tsciulca Iufennls Suvm• U. S. DEPARTMENT OF COMMERCE 2 z z 0 0 ~ > o CI2LI...00 4 bO >~ d) cn q 00 ca (n~ -0E 4) fl) U C 0 E CD o :Cu -V 0. Cau . .t $4 Cu a X k) 04. " # Cu c.. - u 0- u c0 E Q =E 0 ca- 1 ca 4).,u 04$ = a )E ==r

Microwave purification of large-area horizontally aligned arrays of single-walled carbon nanotubes.

PubMed

Xie, Xu; Jin, Sung Hun; Wahab, Muhammad A; Islam, Ahmad E; Zhang, Chenxi; Du, Frank; Seabron, Eric; Lu, Tianjian; Dunham, Simon N; Cheong, Hou In; Tu, Yen-Chu; Guo, Zhilin; Chung, Ha Uk; Li, Yuhang; Liu, Yuhao; Lee, Jong-Ho; Song, Jizhou; Huang, Yonggang; Alam, Muhammad A; Wilson, William L; Rogers, John A

2014-11-12

Recent progress in the field of single-walled carbon nanotubes (SWNTs) significantly enhances the potential for practical use of this remarkable class of material in advanced electronic and sensor devices. One of the most daunting challenges is in creating large-area, perfectly aligned arrays of purely semiconducting SWNTs (s-SWNTs). Here we introduce a simple, scalable, large-area scheme that achieves this goal through microwave irradiation of aligned SWNTs grown on quartz substrates. Microstrip dipole antennas of low work-function metals concentrate the microwaves and selectively couple them into only the metallic SWNTs (m-SWNTs). The result allows for complete removal of all m-SWNTs, as revealed through systematic experimental and computational studies of the process. As one demonstration of the effectiveness, implementing this method on large arrays consisting of ~20,000 SWNTs completely removes all of the m-SWNTs (~7,000) to yield a purity of s-SWNTs that corresponds, quantitatively, to at least to 99.9925% and likely significantly higher.

Assessment of dry-stone terrace wall degradation with a 3D approach

NASA Astrophysics Data System (ADS)

Djuma, Hakan; Camera, Corrado; Faka, Marina; Bruggeman, Adriana; Hermon, Sorin

2016-04-01

In the Mediterranean basin, terracing is a common element of agricultural lands. Terraces retained by dry-stone walls are used to conserve arable soil, delay erosion processes and retain rainfall runoff. Currently, agricultural land abandonment is widespread in the Mediterranean region leading to terrace wall failure due to lack of maintenance and consequently an increase in soil erosion. The objective of this study is to test the applicability of digital 3D documentation on mountainous agricultural areas for assessing changes in terrace wall geometry, including terrace wall failures and associated soil erosion. The study area is located at 800-1100 m above sea level, in the Ophiolite complex of the Troodos Mountains in Cyprus. Average annual precipitation is 750 mm. Two sites with dry-stone terraces were selected for this study. The first site had a sequence of three terrace walls that were surveyed. The uppermost terrace wall was collapsed at several locations; the middle at few locations; and the lowest was still intact. Three fieldwork campaigns were conducted at this site: during the dry season (initial conditions), the middle and end of the wet season. The second site had one terrace wall that was almost completely collapsed. This terrace was restored during a communal terrace rehabilitation event. Two fieldwork campaigns were conducted for this terrace: before and after the terrace wall restoration. Terrace walls were documented with a set of digital images, and transformed into a 3D point cloud (using web-based services and commercial software - Autodesk 123D catch and Menci Software uMap, respectively). A set of points, registered with the total station and geo-referenced with a GPS, enabled the scaling of the 3D model and aligning the terrace walls within the same reference system. The density (distance between each point) of the reconstructed point clouds is 0.005 m by Umap and 0.025 m by 123D Catch. On the first site, the model analysis identified wall

Cortical Thickness, Surface Area and Subcortical Volume Differentially Contribute to Cognitive Heterogeneity in Parkinson's Disease.

PubMed

Gerrits, Niels J H M; van Loenhoud, Anita C; van den Berg, Stan F; Berendse, Henk W; Foncke, Elisabeth M J; Klein, Martin; Stoffers, Diederick; van der Werf, Ysbrand D; van den Heuvel, Odile A

2016-01-01

Parkinson's disease (PD) is often associated with cognitive deficits, although their severity varies considerably between patients. Recently, we used voxel-based morphometry (VBM) to show that individual differences in gray matter (GM) volume relate to cognitive heterogeneity in PD. VBM does, however, not differentiate between cortical thickness (CTh) and surface area (SA), which might be independently affected in PD. We therefore re-analyzed our cohort using the surface-based method FreeSurfer, and investigated (i) CTh, SA, and (sub)cortical GM volume differences between 93 PD patients and 45 matched controls, and (ii) the relation between these structural measures and cognitive performance on six neuropsychological tasks within the PD group. We found cortical thinning in PD patients in the left pericalcarine gyrus, extending to cuneus, precuneus and lingual areas and left inferior parietal cortex, bilateral rostral middle frontal cortex, and right cuneus, and increased cortical surface area in the left pars triangularis. Within the PD group, we found negative correlations between (i) CTh of occipital areas and performance on a verbal memory task, (ii) SA and volume of the frontal cortex and visuospatial memory performance, and, (iii) volume of the right thalamus and scores on two verbal fluency tasks. Our primary findings illustrate that i) CTh and SA are differentially affected in PD, and ii) VBM and FreeSurfer yield non-overlapping results in an identical dataset. We argue that this discrepancy is due to technical differences and the subtlety of the PD-related structural changes.

Vapor Wall Deposition in Chambers: Theoretical Considerations

NASA Astrophysics Data System (ADS)

McVay, R.; Cappa, C. D.; Seinfeld, J.

2014-12-01

In order to constrain the effects of vapor wall deposition on measured secondary organic aerosol (SOA) yields in laboratory chambers, Zhang et al. (2014) varied the seed aerosol surface area in toluene oxidation and observed a clear increase in the SOA yield with increasing seed surface area. Using a coupled vapor-particle dynamics model, we examine the extent to which this increase is the result of vapor wall deposition versus kinetic limitations arising from imperfect accommodation of organic species into the particle phase. We show that a seed surface area dependence of the SOA yield is present only when condensation of vapors onto particles is kinetically limited. The existence of kinetic limitation can be predicted by comparing the characteristic timescales of gas-phase reaction, vapor wall deposition, and gas-particle equilibration. The gas-particle equilibration timescale depends on the gas-particle accommodation coefficient αp. Regardless of the extent of kinetic limitation, vapor wall deposition depresses the SOA yield from that in its absence since vapor molecules that might otherwise condense on particles deposit on the walls. To accurately extrapolate chamber-derived yields to atmospheric conditions, both vapor wall deposition and kinetic limitations must be taken into account.

Service Networks and Patterns of Utilization: Mental Health Programs, Indian Health Service (IHS). Volume 8: Phoenix Area, 1966-1974.

ERIC Educational Resources Information Center

Attneave, Carolyn L.; Beiser, Morton

The eighth volume in a 10-volume report on the historical development (1966-1973) of the 8 administrative Area Offices of the Indian Health Service (IHS) Mental Health Programs, this report presents information on the Phoenix Area Office and the Tucson Sub-Area Office. Included in this document are: (1) The Context: Political and Geographic (the…

Human Uterine Wall Tension Trajectories and the Onset of Parturition

PubMed Central

Sokolowski, Peter; Saison, Francis; Giles, Warwick; McGrath, Shaun; Smith, David; Smith, Julia; Smith, Roger

2010-01-01

Uterine wall tension is thought to be an important determinant of the onset of labor in pregnant women. We characterize human uterine wall tension using ultrasound from the second trimester of pregnancy until parturition and compare preterm, term and twin pregnancies. A total of 320 pregnant women were followed from first antenatal visit to delivery during the period 2000–2004 at the John Hunter Hospital, NSW, Australia. The uterine wall thickness, length, anterior-posterior diameter and transverse diameter were determined by serial ultrasounds. Subjects were divided into three groups: women with singleton pregnancies and spontaneous labor onset, either preterm or term and women with twin pregnancies. Intrauterine pressure results from the literature were combined with our data to form trajectories for uterine wall thickness, volume and tension for each woman using the prolate ellipsoid method and the groups were compared at 20, 25 and 30 weeks gestation. Uterine wall tension followed an exponential curve, with results increasing throughout pregnancy with the site of maximum tension on the anterior wall. For those delivering preterm, uterine wall thickness was increased compared with term. For twin pregnancies intrauterine volume was increased compared to singletons (), but wall thickness was not. There was no evidence for increased tension in those delivering preterm or those with twin gestations. These data are not consistent with a role for high uterine wall tension as a causal factor in preterm spontaneous labor in singleton or twin gestations. It seems likely that hormonal differences in multiple gestations are responsible for increased rates of preterm birth in this group rather than increased tension. PMID:20585649

Relationship of Terminal Duct Lobular Unit Involution of the Breast with Area and Volume Mammographic Densities

PubMed Central

Gierach, Gretchen L.; Patel, Deesha A.; Pfeiffer, Ruth M.; Figueroa, Jonine D.; Linville, Laura; Papathomas, Daphne; Johnson, Jason M.; Chicoine, Rachael E.; Herschorn, Sally D.; Shepherd, John A.; Wang, Jeff; Malkov, Serghei; Vacek, Pamela M.; Weaver, Donald L.; Fan, Bo; Mahmoudzadeh, Amir Pasha; Palakal, Maya; Xiang, Jackie; Oh, Hannah; Horne, Hisani N.; Sprague, Brian L.; Hewitt, Stephen M.; Brinton, Louise A.; Sherman, Mark E.

2016-01-01

Elevated mammographic density (MD) is an established breast cancer risk factor. Reduced involution of terminal duct lobular units (TDLUs), the histologic source of most breast cancers, has been associated with higher MD and breast cancer risk. We investigated relationships of TDLU involution with area and volumetric MD, measured throughout the breast and surrounding biopsy targets (peri-lesional). Three measures inversely related to TDLU involution (TDLU count/mm2, median TDLU span, median acini count/TDLU) assessed in benign diagnostic biopsies from 348 women, ages 40–65, were related to MD area (quantified with thresholding software) and volume (assessed with a density phantom) by analysis of covariance, stratified by menopausal status and adjusted for confounders. Among premenopausal women, TDLU count was directly associated with percent peri-lesional MD (P-trend=0.03), but not with absolute dense area/volume. Greater TDLU span was associated with elevated percent dense area/volume (P-trend<0.05) and absolute peri-lesional MD (P=0.003). Acini count was directly associated with absolute peri-lesional MD (P=0.02). Greater TDLU involution (all metrics) was associated with increased nondense area/volume (P-trend≤0.04). Among postmenopausal women, TDLU measures were not significantly associated with MD. Among premenopausal women, reduced TDLU involution was associated with higher area and volumetric MD, particularly in peri-lesional parenchyma. Data indicating that TDLU involution and MD are correlated markers of breast cancer risk suggest that associations of MD with breast cancer may partly reflect amounts of at-risk epithelium. If confirmed, these results could suggest a prevention paradigm based on enhancing TDLU involution and monitoring efficacy by assessing MD reduction. PMID:26645278

OSCILLATING LIGHT WALL ABOVE A SUNSPOT LIGHT BRIDGE

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

Yang, Shuhong; Zhang, Jun; Jiang, Fayu

With the high tempo-spatial Interface Region Imaging Spectrograph 1330 Å images, we find that many bright structures are rooted in the light bridge of NOAA 12192, forming a light wall. The light wall is brighter than the surrounding areas, and the wall top is much brighter than the wall body. The New Vacuum Solar Telescope Hα and the Solar Dynamics Observatory 171 and 131 Å images are also used to study the light-wall properties. In 1330, 171, and 131 Å, the top of the wall has a higher emission, while in the Hα line, the wall-top emission is very low.more » The wall body corresponds to bright areas in 1330 Å and dark areas in the other lines. The top of the light wall moves upward and downward successively, performing oscillations in height. The deprojected mean height, amplitude, oscillation velocity, and the dominant period are determined to be 3.6 Mm, 0.9 Mm, 15.4 km s{sup −1}, and 3.9 minutes, respectively. We interpret the oscillations of the light wall as the leakage of p-modes from below the photosphere. The constant brightness enhancement of the wall top implies the existence of some kind of atmospheric heating, e.g., via the persistent small-scale reconnection or the magneto-acoustic waves. In another series of 1330 Å images, we find that the wall top in the upward motion phase is significantly brighter than in the downward phase. This kind of oscillation may be powered by the energy released due to intermittent impulsive magnetic reconnection.« less

The relationship between epicuticular long-chained hydrocarbons and surface area - volume ratios in insects (Diptera, Hymenoptera, Lepidoptera)

PubMed Central

Brückner, Adrian; Heethoff, Michael; Blüthgen, Nico

2017-01-01

Long-chain cuticular hydrocarbons (CHCs) are common components of the epicuticle of terrestrial arthropods. CHC serve as a protective barrier against environmental influences but also act as semiochemicals in animal communication. Regarding the latter aspect, species- or intra-functional group specific CHCs composition and variation are relatively well studied. However, comparative knowledge about the relationship of CHC quantity and their relation to surface area—volume ratios in the context of water loss and protection is fragmentary. Hence, we aim to study the taxon-specific relationship of the CHC amount and surface-area to volume ratio related to their functional role (e.g. in water loss). We focused on flower visiting insects and analyzed the CHC amounts of three insect orders (Hymenoptera, Lepidoptera and Diptera) using gas chromatography—mass spectrometry (GC-MS). We included 113 species from two grassland plots, quantified their CHCs, and measured their body mass and surface area. We found differences in the surface area, CHCs per body mass and the CHC density (= amount of CHCs per surface area) across the three insect taxa. Especially the Hymenoptera had a higher CHC density compared to Diptera and Lepidoptera. CHC density could be explained by surface area-volume ratios in Hymenoptera but not in Diptera and Lepidoptera. Unexpectedly, CHC density decreased with increasing surface area—volume ratios. PMID:28384308

Underground Test Area Subproject Phase I Data Analysis Task. Volume VIII - Risk Assessment Documentation Package

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

None

Volume VIII of the documentation for the Phase I Data Analysis Task performed in support of the current Regional Flow Model, Transport Model, and Risk Assessment for the Nevada Test Site Underground Test Area Subproject contains the risk assessment documentation. Because of the size and complexity of the model area, a considerable quantity of data was collected and analyzed in support of the modeling efforts. The data analysis task was consequently broken into eight subtasks, and descriptions of each subtask's activities are contained in one of the eight volumes that comprise the Phase I Data Analysis Documentation.

Normal age-related brain morphometric changes: nonuniformity across cortical thickness, surface area and gray matter volume?

PubMed

Lemaitre, Herve; Goldman, Aaron L; Sambataro, Fabio; Verchinski, Beth A; Meyer-Lindenberg, Andreas; Weinberger, Daniel R; Mattay, Venkata S

2012-03-01

Normal aging is accompanied by global as well as regional structural changes. While these age-related changes in gray matter volume have been extensively studied, less has been done using newer morphological indexes, such as cortical thickness and surface area. To this end, we analyzed structural images of 216 healthy volunteers, ranging from 18 to 87 years of age, using a surface-based automated parcellation approach. Linear regressions of age revealed a concomitant global age-related reduction in cortical thickness, surface area and volume. Cortical thickness and volume collectively confirmed the vulnerability of the prefrontal cortex, whereas in other cortical regions, such as in the parietal cortex, thickness was the only measure sensitive to the pronounced age-related atrophy. No cortical regions showed more surface area reduction than the global average. The distinction between these morphological measures may provide valuable information to dissect age-related structural changes of the brain, with each of these indexes probably reflecting specific histological changes occurring during aging. Published by Elsevier Inc.

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...

California's western juniper and pinyon-juniper woodlands: area, stand characteristics, wood volume, and fenceposts.

Treesearch

Charles L. Bolsinger

1989-01-01

The results of a statewide inventory of western juniper and pinyon-juniper woodlands are presented. Included are statistics on area of woodland by type and ownership; area of rangeland with scattered juniper and pinyon trees; wood volume by ownership, species, and tree size; juniper fenceposts; tree and stand age distribution; stand characteristics, including overstory...

Very Large Area/Volume Microwave ECR Plasma and Ion Source

NASA Technical Reports Server (NTRS)

Foster, John E. (Inventor); Patterson, Michael J. (Inventor)

2009-01-01

The present invention is an apparatus and method for producing very large area and large volume plasmas. The invention utilizes electron cyclotron resonances in conjunction with permanent magnets to produce dense, uniform plasmas for long life ion thruster applications or for plasma processing applications such as etching, deposition, ion milling and ion implantation. The large area source is at least five times larger than the 12-inch wafers being processed to date. Its rectangular shape makes it easier to accommodate to materials processing than sources that are circular in shape. The source itself represents the largest ECR ion source built to date. It is electrodeless and does not utilize electromagnets to generate the ECR magnetic circuit, nor does it make use of windows.

Computer-assisted stereological analysis of gastric volume during the human embryonic period.

PubMed Central

Macarulla-Sanz, E; Nebot-Cegarra, J; Reina-de la Torre, F

1996-01-01

Morphometric data concerning human embryos and fetuses have become more clinically informative since ultrasound was employed to make prenatal measurements and software preprocessing techniques improved the previous fuzzy ultrasound signals (Mahoney, 1992). The aim of this study was to determine the volume of the human stomach during the embryonic period and to compare its rate of growth with that during the early fetal period. To calculate gastric volume, computer imaging techniques were applied on cross sections of a graded series of human embryos (from Carnegie stage 11) and fetuses. Gastric volume increased progressively, except for a decrease between stages 12 and 13 due principally to the reduction of the right gastric wall. The growth of the left wall of the stomach was predominant over that of the right. Until stage 20 the stomach volume increased due to the predominant growth of the walls, after this stage the gastric cavity volume increased rapidly, and the rate of growth of the gastric volume reached similar values to that of the early fetal period. We concluded that in the beginning the human stomach grows due to the predominant growth of its walls, chiefly of the left, and from stage 20 because of the predominant expansion of its cavity, which may be related to the capacity to swallow amniotic fluid at the end of the embryonic period. The diminution of the right gastric wall volume (stages 12-13) is consistent with an extension of the omental bursa into the mesodermal anlage of the stomach. PMID:8621339

Predicting Chest Wall Pain From Lung Stereotactic Body Radiotherapy for Different Fractionation Schemes

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

Woody, Neil M.; Videtic, Gregory M.M.; Stephans, Kevin L.

Purpose: Recent studies with two fractionation schemes predicted that the volume of chest wall receiving >30 Gy (V30) correlated with chest wall pain after stereotactic body radiation therapy (SBRT) to the lung. This study developed a predictive model of chest wall pain incorporating radiobiologic effects, using clinical data from four distinct SBRT fractionation schemes. Methods and Materials: 102 SBRT patients were treated with four different fractionations: 60 Gy in three fractions, 50 Gy in five fractions, 48 Gy in four fractions, and 50 Gy in 10 fractions. To account for radiobiologic effects, a modified equivalent uniform dose (mEUD) model calculatedmore » the dose to the chest wall with volume weighting. For comparison, V30 and maximum point dose were also reported. Using univariable logistic regression, the association of radiation dose and clinical variables with chest wall pain was assessed by uncertainty coefficient (U) and C statistic (C) of receiver operator curve. The significant associations from the univariable model were verified with a multivariable model. Results: 106 lesions in 102 patients with a mean age of 72 were included, with a mean of 25.5 (range, 12-55) months of follow-up. Twenty patients reported chest wall pain at a mean time of 8.1 (95% confidence interval, 6.3-9.8) months after treatment. The mEUD models, V30, and maximum point dose were significant predictors of chest wall pain (p < 0.0005). mEUD improved prediction of chest wall pain compared with V30 (C = 0.79 vs. 0.77 and U = 0.16 vs. 0.11). The mEUD with moderate weighting (a = 5) better predicted chest wall pain than did mEUD without weighting (a = 1) (C = 0.79 vs. 0.77 and U = 0.16 vs. 0.14). Body mass index (BMI) was significantly associated with chest wall pain (p = 0.008). On multivariable analysis, mEUD and BMI remained significant predictors of chest wall pain (p = 0.0003 and 0.03, respectively). Conclusion: mEUD with moderate weighting better predicted chest wall pain

Far-field potentials in cylindrical and rectangular volume conductors.

PubMed

Dumitru, D; King, J C; Rogers, W E

1993-07-01

The occurrence of a transient dipole is one method of producing a far-field potential. This investigation qualitatively defines the characteristics of the near-field and far-field electrical potentials produced by a transient dipole in both cylindrical and rectangular volume conductors. Most body segments of electrophysiologic interest such as arms, legs, thorax, and neck are roughly cylindrical in shape. A centrally located dipole generator produces a nonzero equipotential region which is found to occur along the cylindrical wall at a distance from the dipole of approximately 1.4 times the cylinder's radius and 1.9 times the cylinder's radius for the center of the cylinder. This distance to the equi-potential zone along the surface wall expands but remains less than 3.0 times the cylindrical radius when the dipole is eccentrically placed. The magnitude of the equipotential region resulting from an asymmetrically placed dipole remains identical to that when the dipole is centrally located. This behavior is found to be very similar in rectangular shallow conducting volumes that model a longitudinal slice of the cylinder, thus allowing a simple experimental model of the cylinder to be utilized. Amplitudes of the equipotential region are inversely proportional to the cylindrical or rectangular volume's cross-sectional area at the location of dipolar imbalance. This study predicts that referential electrode montages, when placed at 3.0 times the radius or greater from a dipolar axially aligned far-field generator in cylindrical homogeneous volume conductors, will record only equipotential far-field effects.

Dose-volume parameters predict for the development of chest wall pain after stereotactic body radiation for lung cancer.

PubMed

Mutter, Robert W; Liu, Fan; Abreu, Andres; Yorke, Ellen; Jackson, Andrew; Rosenzweig, Kenneth E

2012-04-01

Chest wall (CW) pain has recently been recognized as an important adverse effect of stereotactic body radiation therapy (SBRT) for non-small-cell lung cancer (NSCLC). We developed a dose-volume model to predict the development of this toxicity. A total of 126 patients with primary, clinically node-negative NSCLC received three to five fractions of SBRT to doses of 40-60 Gy and were prospectively followed. The dose-absolute volume histograms of two different definitions of the CW as an organ at risk (CW3cm and CW2cm) were examined for all 126 patients. With a median follow-up of 16 months, the 2-year estimated actuarial incidence of Grade ≥ 2 CW pain was 39%. The median time to onset of Grade ≥ 2 CW pain (National Cancer Institute Common Terminology Criteria for Adverse Events, Version 3.0) was 9 months. There was no predictive advantage for biologically corrected dose over physical dose. Neither fraction number (p = 0.07) nor prescription dose (p = 0.07) were significantly correlated with the development of Grade ≥ 2 CW pain. Cox Proportional Hazards analysis identified significant correlation with a broad range of dose-volume combinations, with the CW volume receiving 30 Gy (V30) as one of the strongest predictors (p < 0.001). CW2cm consistently enabled better prediction of CW toxicity. When a physical dose of 30 Gy was received by more than 70 cm(3) of CW2cm, there was a significant correlation with Grade ≥ 2 CW pain (p = 0.004). CW toxicity after SBRT is common and long-term follow-up is needed to identify affected patients. A volume of CW ≥ 70 cm(3) receiving 30 Gy is significantly correlated with Grade ≥ 2 CW pain. We are currently applying this constraint at our institution for patients receiving thoracic SBRT. An actuarial atlas of our data is provided as an electronic supplement to facilitate data-sharing and meta-analysis relating to CW pain. Copyright © 2012 Elsevier Inc. All rights reserved.

Dose-Volume Parameters Predict for the Development of Chest Wall Pain After Stereotactic Body Radiation for Lung Cancer

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

Mutter, Robert W.; Liu Fan; Abreu, Andres

Purpose: Chest wall (CW) pain has recently been recognized as an important adverse effect of stereotactic body radiation therapy (SBRT) for non-small-cell lung cancer (NSCLC). We developed a dose-volume model to predict the development of this toxicity. Methods and Materials: A total of 126 patients with primary, clinically node-negative NSCLC received three to five fractions of SBRT to doses of 40-60 Gy and were prospectively followed. The dose-absolute volume histograms of two different definitions of the CW as an organ at risk (CW3cm and CW2cm) were examined for all 126 patients. Results: With a median follow-up of 16 months, themore » 2-year estimated actuarial incidence of Grade {>=} 2 CW pain was 39%. The median time to onset of Grade {>=} 2 CW pain (National Cancer Institute Common Terminology Criteria for Adverse Events, Version 3.0) was 9 months. There was no predictive advantage for biologically corrected dose over physical dose. Neither fraction number (p = 0.07) nor prescription dose (p = 0.07) were significantly correlated with the development of Grade {>=} 2 CW pain. Cox Proportional Hazards analysis identified significant correlation with a broad range of dose-volume combinations, with the CW volume receiving 30 Gy (V30) as one of the strongest predictors (p < 0.001). CW2cm consistently enabled better prediction of CW toxicity. When a physical dose of 30 Gy was received by more than 70 cm{sup 3} of CW2cm, there was a significant correlation with Grade {>=} 2 CW pain (p = 0.004). Conclusions: CW toxicity after SBRT is common and long-term follow-up is needed to identify affected patients. A volume of CW {>=} 70 cm{sup 3} receiving 30 Gy is significantly correlated with Grade {>=} 2 CW pain. We are currently applying this constraint at our institution for patients receiving thoracic SBRT. An actuarial atlas of our data is provided as an electronic supplement to facilitate data-sharing and meta-analysis relating to CW pain.« less

The electrostatic properties of Fiber-Reinforced-Plastics double wall underground storage gasoline tanks

NASA Astrophysics Data System (ADS)

Li, Yipeng; Liu, Quanzhen; Meng, He; Sun, Lifu; Zhang, Yunpeng

2013-03-01

At present Fiber Reinforced Plastics (FRP) double wall underground storage gasoline tanks are wildly used. An FRP product with a resistance of more than 1011 Ω is a static non-conductor, so it is difficult for the static electricity in the FRP product to decay into the earth. In this paper an experimental system was built to simulate an automobile gasoline filling station. Some electrostatic parameters of the gasoline, including volume charge density, were tested when gasoline was unloaded into a FRP double wall underground storage tank. Measurements were taken to make sure the volume charge density in the oil-outlet was similar to the volume charge density in the tank. In most cases the volume charge density of the gasoline was more than 22.7 μC m-3, which is likely to cause electrostatic discharge in FRP double wall underground storage gasoline tanks. On the other hand, it would be hard to ignite the vapor by electrostatic discharge since the vapor pressure in the tanks is over the explosion limit. But when the tank is repaired or re-used, the operators must pay attention to the static electricity and some measurements should be taken to avoid electrostatic accident. Besides the relaxation time of charge in the FRP double wall gasoline storage tanks should be longer.

Investigation of Plant Cell Wall Properties: A Study of Contributions from the Nanoscale to the Macroscale Impacting Cell Wall Recalcitrance

NASA Astrophysics Data System (ADS)

Crowe, Jacob Dillon

, alkaline hydrogen peroxide and liquid hot water pretreatments were shown to alter structural properties impacting nanoscale porosity in corn stover. Delignification by alkaline hydrogen peroxide pretreatment decreased cell wall rigidity, with subsequent cell wall swelling resulting in increased nanoscale porosity and improved enzymatic hydrolysis compared to limited swelling and increased accessible surface areas observed in liquid hot water pretreated biomass. The volume accessible to a 90 A dextran probe within the cell wall was found to be positively correlated to both enzyme binding and glucose hydrolysis yields, indicating cell wall porosity is a key contributor to effective hydrolysis yields. In the third study, the effect of altered xylan content and structure was investigated in irregular xylem (irx) Arabidopsis thaliana mutants to understand the role xylan plays in secondary cell wall development and organization. Higher xylan extractability and lower cellulose crystallinity observed in irx9 and irx15 irx15-L mutants compared to wild type indicated altered xylan integration into the secondary cell wall. Nanoscale cell wall organization observed using multiple microscopy techniques was impacted to some extent in all irx mutants, with disorganized cellulose microfibril layers in sclerenchyma secondary cell walls likely resulting from irregular xylan structure and content. Irregular secondary cell wall microfibril layers showed heterogeneous nanomechanical properties compared to wild type, which translated to mechanical deficiencies observed in stem tensile tests. These results suggest nanoscale defects in cell wall strength can correspond to macroscale phenotypes.

Service Networks and Patterns of Utilization: Mental Health Programs, Indian Health Service (IHS). Volume 5: Billings Area, 1963-1973.

ERIC Educational Resources Information Center

Attneave, Carolyn L.; Beiser, Morton

The fifth volume in a 10-volume report on the historical development (1966-1973) of the 8 administrative Area Offices of the Indian Health Service (IHS) Mental Health Programs, this report presents information on the Billings Area Office. Included in this document are: (1) General Description (geography, demography, and transportation facilities…

Calculation of wall effects of flow on a perforated wall with a code of surface singularities

NASA Astrophysics Data System (ADS)

Piat, J. F.

1994-07-01

Simplifying assumptions are inherent in the analytic method previously used for the determination of wall interferences on a model in a wind tunnel. To eliminate these assumptions, a new code based on the vortex lattice method was developed. It is suitable for processing any shape of test sections with limited areas of porous wall, the characteristic of which can be nonlinear. Calculation of wall effects in S3MA wind tunnel, whose test section is rectangular 0.78 m x 0.56 m, and fitted with two or four perforated walls, have been performed. Wall porosity factors have been adjusted to obtain the best fit between measured and computed pressure distributions on the test section walls. The code was checked by measuring nearly equal drag coefficients for a model tested in S3MA wind tunnel (after wall corrections) and in S2MA wind tunnel whose test section is seven times larger (negligible wall corrections).

The Genetic Association Between Neocortical Volume and General Cognitive Ability Is Driven by Global Surface Area Rather Than Thickness.

PubMed

Vuoksimaa, Eero; Panizzon, Matthew S; Chen, Chi-Hua; Fiecas, Mark; Eyler, Lisa T; Fennema-Notestine, Christine; Hagler, Donald J; Fischl, Bruce; Franz, Carol E; Jak, Amy; Lyons, Michael J; Neale, Michael C; Rinker, Daniel A; Thompson, Wesley K; Tsuang, Ming T; Dale, Anders M; Kremen, William S

2015-08-01

Total gray matter volume is associated with general cognitive ability (GCA), an association mediated by genetic factors. It is expectable that total neocortical volume should be similarly associated with GCA. Neocortical volume is the product of thickness and surface area, but global thickness and surface area are unrelated phenotypically and genetically in humans. The nature of the genetic association between GCA and either of these 2 cortical dimensions has not been examined. Humans possess greater cognitive capacity than other species, and surface area increases appear to be the primary driver of the increased size of the human cortex. Thus, we expected neocortical surface area to be more strongly associated with cognition than thickness. Using multivariate genetic analysis in 515 middle-aged twins, we demonstrated that both the phenotypic and genetic associations between neocortical volume and GCA are driven primarily by surface area rather than thickness. Results were generally similar for each of 4 specific cognitive abilities that comprised the GCA measure. Our results suggest that emphasis on neocortical surface area, rather than thickness, could be more fruitful for elucidating neocortical-GCA associations and identifying specific genes underlying those associations. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Volume and surface area size distribution, water mass and model fitting of GCE/CASE/WATOX marine aerosols

NASA Astrophysics Data System (ADS)

Kim, Y.; Sievering, H.; Boatman, J.

1990-06-01

As a part of the Global Change Expedition/Coordinated Air-Sea Experiment/Western Atlantic Ocean Experiment (GCE/CASE/WATOX), size distributions of marine aerosols were measured at two altitudes of about 2750 and 150 m above sea level (asl) over the size range 0.1 ˜ 32 μm. Lognormal fitting was applied to the corrected aerosol size spectra to determine the volume and surface area size distributions of the CASE-WATOX marine aerosols. Each aerosol size distribution was fitted with three lognormal distributions representing fine-, large-, and giant-particle modes. Water volume fraction and dry particle size of each aerosol size distribution were also calculated using empirical formulas for particle size as a function of relative humidity and particle type. Because of the increased influence from anthropogenic sources in the continental United States, higher aerosol volume concentrations were observed in the fine-particle mode near-shore off the east coast; 2.11 and 3.63 μm3 cm-3 for free troposphere (FT) and marine boundary layer (MBL), compared with the open-sea Bermuda area values; 0.13 and 0.74 μm3 cm-3 for FT and MBL. The large-particle mode exhibits the least variations in volume distributions between the east coast and open-sea Bermuda area, having a volume geometric median diameter (VGMD) between 1.4 and 1.6 μm and a geometric standard deviation between 1.57 and 1.68. For the giant-particle mode, larger VGMD and volume concentrations were observed for marine aerosols nearshore off the east coast than in the open-sea Bermuda area because of higher relative humidity and higher surface wind speed conditions. Wet VGMD and aerosol water volume concentrations at 15 m asl ship level were determined by extrapolating from those obtained by analysis of the CASE-WATOX aircraft aerosol data. Abundance of aerosol water in the MBL serves as an important pathway for heterogeneous conversion of SO2 in sea salt aerosol particles.

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.

A new fractional order derivative based active contour model for colon wall segmentation

NASA Astrophysics Data System (ADS)

Chen, Bo; Li, Lihong C.; Wang, Huafeng; Wei, Xinzhou; Huang, Shan; Chen, Wensheng; Liang, Zhengrong

2018-02-01

Segmentation of colon wall plays an important role in advancing computed tomographic colonography (CTC) toward a screening modality. Due to the low contrast of CT attenuation around colon wall, accurate segmentation of the boundary of both inner and outer wall is very challenging. In this paper, based on the geodesic active contour model, we develop a new model for colon wall segmentation. First, tagged materials in CTC images were automatically removed via a partial volume (PV) based electronic colon cleansing (ECC) strategy. We then present a new fractional order derivative based active contour model to segment the volumetric colon wall from the cleansed CTC images. In this model, the regionbased Chan-Vese model is incorporated as an energy term to the whole model so that not only edge/gradient information but also region/volume information is taken into account in the segmentation process. Furthermore, a fractional order differentiation derivative energy term is also developed in the new model to preserve the low frequency information and improve the noise immunity of the new segmentation model. The proposed colon wall segmentation approach was validated on 16 patient CTC scans. Experimental results indicate that the present scheme is very promising towards automatically segmenting colon wall, thus facilitating computer aided detection of initial colonic polyp candidates via CTC.

A pilot study on bladder wall thickness at different filling stages

NASA Astrophysics Data System (ADS)

Zhang, Xi; Liu, Yang; Li, Baojuan; Zhang, Guopeng; Liang, Zhengrong; Lu, Hongbing

2015-03-01

The ever-growing death rate and the high recurrence of bladder cancer make the early detection and appropriate followup procedure of bladder cancer attract more attention. Compare to optical cystoscopy, image-based studies have revealed its potentials in non-invasive observations of the abnormities of bladder recently, in which MR imaging turns out to be a better choice for bladder evaluation due to its non-ionizing and high contrast between urine and wall tissue. Recent studies indicate that bladder wall thickness tends to be a good indicator for detecting bladder wall abnormalities. However, it is difficult to quantitatively compare wall thickness of the same subject at different filling stages or among different subjects. In order to explore thickness variations at different bladder filling stages, in this study, we preliminarily investigate the relationship between bladder wall thickness and bladder volume based on a MRI database composed of 40 datasets acquired from 10 subjects at different filling stages, using a pipeline for thickness measurement and analysis proposed in our previous work. The Student's t-test indicated that there was no significant different on wall thickness between the male group and the female group. The Pearson correlation analysis result indicated that negative correlation with a correlation coefficient of -0.8517 existed between the wall thickness and bladder volume, and the correlation was significant(p <0.01). The corresponding linear regression equation was then estimated by the unary linear regression. Compared to the absolute value of wall thickness, the z-score of wall thickness would be more appropriate to reflect the thickness variations. For possible abnormality detection of a bladder based on wall thickness, the intra-subject and inter-subject thickness variation should be considered.

Service Networks and Patterns of Utilization: Mental Health Programs, Indian Health Service (IHS). Volume 9: Portland Area, 1966-1973.

ERIC Educational Resources Information Center

Attneave, Carolyn L.; Beiser, Morton

The ninth volume in a 10-volume report on the historical development (1966-1973) of the 8 administrative Area Offices of the Indian Health Service (IHS) Mental Health Programs, this report presents information on the Portland Area Office. Included in this document are: (1) The Context (early history of the Oregon Territory, geography and tribal…

Evaluation of Aortic Blood Flow and Wall Shear Stress in Aortic Stenosis and Its Association With Left Ventricular Remodeling.

PubMed

von Knobelsdorff-Brenkenhoff, Florian; Karunaharamoorthy, Achudhan; Trauzeddel, Ralf Felix; Barker, Alex J; Blaszczyk, Edyta; Markl, Michael; Schulz-Menger, Jeanette

2016-03-01

Aortic stenosis (AS) leads to variable stress for the left ventricle (LV) and consequently a broad range of LV remodeling. The aim of this study was to describe blood flow patterns in the ascending aorta of patients with AS and determine their association with remodeling. Thirty-seven patients with AS (14 mild, 8 moderate, 15 severe; age, 63±13 years) and 37 healthy controls (age, 60±10 years) underwent 4-dimensional-flow magnetic resonance imaging. Helical and vortical flow formations and flow eccentricity were assessed in the ascending aorta. Normalized flow displacement from the vessel center and peak systolic wall shear stress in the ascending aorta were quantified. LV remodeling was assessed based on LV mass index and the ratio of LV mass:end-diastolic volume (relative wall mass). Marked helical and vortical flow formation and eccentricity were more prevalent in patients with AS than in healthy subjects, and patients with AS exhibited an asymmetrical and elevated distribution of peak systolic wall shear stress. In AS, aortic orifice area was strongly negatively associated with vortical flow formation (P=0.0274), eccentricity (P=0.0070), and flow displacement (P=0.0021). Bicuspid aortic valve was associated with more intense helical (P=0.0098) and vortical flow formation (P=0.0536), higher flow displacement (P=0.11), and higher peak systolic wall shear stress (P=0.0926). LV mass index and relative wall mass were significantly associated with aortic orifice area (P=0.0611, P=0.0058) and flow displacement (P=0.0058, P=0.0283). In this pilot study, AS leads to abnormal blood flow pattern and peak systolic wall shear stress in the ascending aorta. In addition to aortic orifice area, normalized flow displacement was significantly associated with LV remodeling. © 2016 American Heart Association, Inc.

Underground Test Area Subproject Phase I Data Analysis Task. Volume VII - Tritium Transport Model Documentation Package

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

None

Volume VII of the documentation for the Phase I Data Analysis Task performed in support of the current Regional Flow Model, Transport Model, and Risk Assessment for the Nevada Test Site Underground Test Area Subproject contains the tritium transport model documentation. Because of the size and complexity of the model area, a considerable quantity of data was collected and analyzed in support of the modeling efforts. The data analysis task was consequently broken into eight subtasks, and descriptions of each subtask's activities are contained in one of the eight volumes that comprise the Phase I Data Analysis Documentation.

Improved fire protection system for underground fueling areas. Volume II. Final report Sep 77-Oct 81

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

McDonald, L.; Kennedy, D.; Reid, G.

1981-10-01

The objectives of this investigation were to (1) develop safe practice guidelines that will minimize the chance of fires in underground fueling areas and (2) to develop a low-cost, reliable, automatic fire control system (AFCS) for underground fueling areas. Volume I of the report covered the period from June 21, 1976, to September 30, 1977, and included (1) the preparation of safe practice guidelines for underground fueling areas; (2) preparation of recommended AFCS design concepts for underground fueling areas; and (3) the design, fabrication, and in-mine fire test of an AFCS at Pine Creek Mine, Bishop, Calif. Volume II ofmore » the report covers the period from September 30, 1977, to September 30, 1981, and includes (1) a long-term validation test of the AFCS in the Pine Creek Mine, (2) a study of the environmental effects of aqueous film-forming foam, (3) the design and installation of a system at AMAX Buick Mine, Boss, Mo., (4) the design of a system for enclosed fuel areas, and (5) the design of a system for semipermanent fueling areas.« less

Immersion Refractometry of Isolated Bacterial Cell Walls

PubMed Central

Marquis, Robert E.

1973-01-01

Immersion-refractometric and light-scattering measurements were adapted to determinations of average refractive indices and physical compactness of isolated bacterial cell walls. The structures were immersed in solutions containing various concentrations of polymer molecules that cannot penetrate into wall pores, and then an estimate was made of the polymer concentration or the refractive index of the polymer solution in which light scattering was reduced to zero. Because each wall preparation was heterogeneous, the refractive index of the medium for zero light scattering had to be estimated by extrapolation. Refractive indices for walls suspended in bovine serum albumin solutions ranged from 1.348 for walls of the rod form of Arthrobacter crystallopoietes to 1.382 for walls of the teichoic acid deficient, 52A5 strain of Staphylococcus aureus. These indices were used to calculate approximate values for solids content per milliliter, and the calculated values agreed closely with those estimated from a knowledge of dextran-impermeable volumes per gram, dry weight, of the walls. When large molecules such as dextrans or serum albumin were used for immersion refractometry, the refractive indices obtained were for entire walls, including both wall polymers and wall water. When smaller molecules that can penetrate wall pores to various extents were used with Micrococcus lysodeikticus walls, the average, apparent refractive index of the structures increased as the molecular size of probing molecules was decreased. It was possible to obtain an estimate of 1.45 to 1.46 for the refractive index of wall polymers, predominantly peptidoglycans in this case, by extrapolating the curve for refractive index versus molecular radius to a value of 0.2 nm, the approximate radius of a water molecule. This relatively low value for polymer refractive index was interpreted as evidence in favor of the amorphous, elastic model of peptidoglycan structure and against the crystalline, rigid

Effect of Inhibition of Deoxyribonucleic Acid and Protein Synthesis on the Direction of Cell Wall Growth in Streptococcus faecalis

PubMed Central

Higgins, M. L.; Daneo-Moore, L.; Boothby, D.; Shockman, G. D.

1974-01-01

Selective inhibition of protein synthesis in Streptococcus faecalis (ATCC 9790) was accompanied by a rapid and severe inhibition of cell division and a reduction of enlargement of cellular surface area. Continued synthesis of cell wall polymers resulted in rapid thickening of the wall to an extent not seen in exponential-phase populations. Thus, the normal direction of wall growth was changed from a preferential feeding out of new wall surface to that of thickening existing cell surfaces. However, the overall manner in which the wall thickened, from nascent septa toward polar regions, was the same in both exponential-phase and inhibited populations. In contrast, selective inhibition of deoxyribonucleic acid (DNA) synthesis using mitomycin C was accompanied by an increase in cellular surface area and by division of about 80% of the cells in random populations. Little or no wall thickening was observed until the synthesis of macromolecules other than DNA was impaired and further cell division ceased. Concomitant inhibition of both DNA and protein synthesis inhibited cell division but permitted an increase in average cell volume. In such doubly inhibited cells, walls thickened less than in cells inhibited for protein synthesis only. On the basis of the results obtained, a model for cell surface enlargement and cell division is presented. The model proposes that: (i) each wall enlargement site is influenced by an individual chromosome replication cycle; (ii) during chromosome replication peripheral surface enlargement would be favored over thickening (or septation); (iii) a signal associated with chromosome termination would favor thickening (and septation) at the expense of surface enlargement; and (iv) a factor or signal related to protein synthesis would be required for one or more of the near terminal stages of cell division or cell separation, or both. Images PMID:4133352

Rain volume estimation over areas using satellite and radar data

NASA Technical Reports Server (NTRS)

Doneaud, A. A.; Vonderhaar, T. H.

1985-01-01

The feasibility of rain volume estimation over fixed and floating areas was investigated using rapid scan satellite data following a technique recently developed with radar data, called the Area Time Integral (ATI) technique. The radar and rapid scan GOES satellite data were collected during the Cooperative Convective Precipitation Experiment (CCOPE) and North Dakota Cloud Modification Project (NDCMP). Six multicell clusters and cells were analyzed to the present time. A two-cycle oscillation emphasizing the multicell character of the clusters is demonstrated. Three clusters were selected on each day, 12 June and 2 July. The 12 June clusters occurred during the daytime, while the 2 July clusters during the nighttime. A total of 86 time steps of radar and 79 time steps of satellite images were analyzed. There were approximately 12-min time intervals between radar scans on the average.

A new methodological approach to assess cardiac work by pressure-volume and stress-length relations in patients with aortic valve stenosis and dilated cardiomyopathy.

PubMed

Alter, P; Rupp, H; Rominger, M B; Klose, K J; Maisch, B

2008-01-01

In experimental animals, cardiac work is derived from pressure-volume area and analyzed further using stress-length relations. Lack of methods for determining accurately myocardial mass has until now prevented the use of stress-length relations in patients. We hypothesized, therefore, that not only pressure-volume loops but also stress-length diagrams can be derived from cardiac volume and cardiac mass as assessed by cardiac magnetic resonance imaging (CMR) and invasively measured pressure. Left ventricular (LV) volume and myocardial mass were assessed in seven patients with aortic valve stenosis (AS), eight with dilated cardiomyopathy (DCM), and eight controls using electrocardiogram (ECG)-gated CMR. LV pressure was measured invasively. Pressure-volume curves were calculated based on ECG triggering. Stroke work was assessed as area within the pressure-volume loop. LV wall stress was calculated using a thick-wall sphere model. Similarly, stress-length loops were calculated to quantify stress-length-based work. Taking the LV geometry into account, the normalization with regard to ventricular circumference resulted in "myocardial work." Patients with AS (valve area 0.73+/-0.18 cm(2)) exhibited an increased LV myocardial mass when compared with controls (P<0.05). LV wall stress was increased in DCM but not in AS. Stroke work of AS was unchanged when compared with controls (0.539+/-0.272 vs 0.621+/-0.138 Nm, not significant), whereas DCM exhibited a significant depression (0.367+/-0.157 Nm, P<0.05). Myocardial work was significantly reduced in both AS and DCM when compared with controls (129.8+/-69.6, 200.6+/-80.1, 332.2+/-89.6 Nm/m(2), P<0.05), also after normalization (7.40+/-5.07, 6.27+/-3.20, 14.6+/-4.07 Nm/m(2), P<0.001). It is feasible to obtain LV pressure-volume and stress-length diagrams in patients based on the present novel methodological approach of using CMR and invasive pressure measurement. Myocardial work was reduced in patients with DCM and noteworthy

Variability of magnetoencephalographic sensor sensitivity measures as a function of age, brain volume and cortical area

PubMed Central

Irimia, Andrei; Erhart, Matthew J.; Brown, Timothy T.

2014-01-01

Objective To assess the feasibility and appropriateness of magnetoencephalography (MEG) for both adult and pediatric studies, as well as for the developmental comparison of these factors across a wide range of ages. Methods For 45 subjects with ages from 1 to 24 years (infants, toddlers, school-age children and young adults), lead fields (LFs) of MEG sensors are computed using anatomically realistic boundary element models (BEMs) and individually-reconstructed cortical surfaces. Novel metrics are introduced to quantify MEG sensor focality. Results The variability of MEG focality is graphed as a function of brain volume and cortical area. Statistically significant differences in total cerebral volume, cortical area, MEG global sensitivity and LF focality are found between age groups. Conclusions Because MEG focality and sensitivity differ substantially across the age groups studied, the cortical LF maps explored here can provide important insights for the examination and interpretation of MEG signals from early childhood to young adulthood. Significance This is the first study to (1) investigate the relationship between MEG cortical LFs and brain volume as well as cortical area across development, and (2) compare LFs between subjects with different head sizes using detailed cortical reconstructions. PMID:24589347

Neural mechanisms of volume regulation.

PubMed

DiBona, G F

1983-05-01

Under steady-state conditions, urinary sodium excretion matches dietary sodium intake. Because extracellular fluid osmolality is tightly regulated, the quantity of sodium in the extracellular fluid determines the volume of this compartment. The left atrial volume receptor mechanism is an example of a neural mechanism of volume regulation. The left atrial mechanoreceptor, which functions as a sensor in the low-pressure vascular system, has a well-defined compliance relating intravascular volume to filling pressure and responds to changes in wall tension by discharging into afferent vagal fibers. These fibers have appropriate central nervous system representation whose related efferent neurohumoral mechanisms regulate thirst, renal excretion of water and sodium, and the redistribution of the extracellular fluid volume.

Retroperitoneal sarcoma (RPS) high risk gross tumor volume boost (HR GTV boost) contour delineation agreement among NRG sarcoma radiation and surgical oncologists.

PubMed

Baldini, Elizabeth H; Bosch, Walter; Kane, John M; Abrams, Ross A; Salerno, Kilian E; Deville, Curtiland; Raut, Chandrajit P; Petersen, Ivy A; Chen, Yen-Lin; Mullen, John T; Millikan, Keith W; Karakousis, Giorgos; Kendrick, Michael L; DeLaney, Thomas F; Wang, Dian

2015-09-01

Curative intent management of retroperitoneal sarcoma (RPS) requires gross total resection. Preoperative radiotherapy (RT) often is used as an adjuvant to surgery, but recurrence rates remain high. To enhance RT efficacy with acceptable tolerance, there is interest in delivering "boost doses" of RT to high-risk areas of gross tumor volume (HR GTV) judged to be at risk for positive resection margins. We sought to evaluate variability in HR GTV boost target volume delineation among collaborating sarcoma radiation and surgical oncologist teams. Radiation planning CT scans for three cases of RPS were distributed to seven paired radiation and surgical oncologist teams at six institutions. Teams contoured HR GTV boost volumes for each case. Analysis of contour agreement was performed using the simultaneous truth and performance level estimation (STAPLE) algorithm and kappa statistics. HRGTV boost volume contour agreement between the seven teams was "substantial" or "moderate" for all cases. Agreement was best on the torso wall posteriorly (abutting posterior chest abdominal wall) and medially (abutting ipsilateral para-vertebral space and great vessels). Contours varied more significantly abutting visceral organs due to differing surgical opinions regarding planned partial organ resection. Agreement of RPS HRGTV boost volumes between sarcoma radiation and surgical oncologist teams was substantial to moderate. Differences were most striking in regions abutting visceral organs, highlighting the importance of collaboration between the radiation and surgical oncologist for "individualized" target delineation on the basis of areas deemed at risk and planned resection.

Intensity modulated radiation-therapy for preoperative posterior abdominal wall irradiation of retroperitoneal liposarcomas

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

Bossi, Alberto; De Wever, Ivo; Van Limbergen, Erik

2007-01-01

Purpose: Preoperative external-beam radiation therapy (preop RT) in the management of Retroperitoneal Liposarcomas (RPLS) typically involves the delivery of radiation to the entire tumor mass: yet this may not be necessary. The purpose of this study is to evaluate a new strategy of preop RT for RPLS in which the target volume is limited to the contact area between the tumoral mass and the posterior abdominal wall. Methods and Materials: Between June 2000 and Jan 2005, 18 patients with the diagnosis of RPLS have been treated following a pilot protocol of pre-op RT, 50 Gy in 25 fractions of 2more » Gy/day. The Clinical Target Volume (CTV) has been limited to the posterior abdominal wall, region at higher risk for local relapse. A Three-Dimensional conformal (3D-CRT) and an Intensity Modulated (IMRT) plan were generated and compared; toxicity was reported following the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events v3.0. Results: All patients completed the planned treatment and the acute toxicity was tolerable: 2 patients experienced Grade 3 and 1 Grade 2 anorexia while 2 patients developed Grade 2 nausea. IMRT allows a better sparing of the ipsilateral and the contralateral kidney. All tumors were successfully resected without major complications. At a median follow-up of 27 months 2 patients developed a local relapse and 1 lung metastasis. Conclusions: Our strategy of preop RT is feasible and well tolerated: the rate of resectability is not compromised by limiting the preop CTV to the posterior abdominal wall and a better critical-structures sparing is obtained with IMRT.« less

Excess plasma membrane and effects of ionic amphipaths on mechanics of outer hair cell lateral wall.

PubMed

Morimoto, Noriko; Raphael, Robert M; Nygren, Anders; Brownell, William E

2002-05-01

The interaction between the outer hair cell (OHC) lateral wall plasma membrane and the underlying cortical lattice was examined by a morphometric analysis of cell images during cell deformation. Vesiculation of the plasma membrane was produced by micropipette aspiration in control cells and cells exposed to ionic amphipaths that alter membrane mechanics. An increase of total cell and vesicle surface area suggests that the plasma membrane possesses a membrane reservoir. Chlorpromazine (CPZ) decreased the pressure required for vesiculation, whereas salicylate (Sal) had no effect. The time required for vesiculation was decreased by CPZ, indicating that CPZ decreases the energy barrier required for vesiculation. An increase in total volume is observed during micropipette aspiration. A deformation-induced increase in hydraulic conductivity is also seen in response to micropipette-applied fluid jet deformation of the lateral wall. Application of CPZ and/or Sal decreased this strain-induced hydraulic conductivity. The impact of ionic amphipaths on OHC plasma membrane and lateral wall mechanics may contribute to their effects on OHC electromotility and hearing.

Landslides and rock fall processes in the proglacial area of the Gepatsch glacier, Tyrol, Austria - Quantitative assessment of controlling factors and process rates

NASA Astrophysics Data System (ADS)

Vehling, Lucas; Rohn, Joachim; Moser, Michael

2013-04-01

Due to the rapid deglaciation since 1850, lithological structures and topoclimatic factors, mass movements like rock fall, landslides and complex processes are important contributing factors to sediment transport and modification of the earth's surface in the steep, high mountain catchment of the Gepatsch reservoir. Contemporary geotechnical processes, mass movement deposits, their source areas, and controlling factors like material properties and relief parameters are mapped in the field, on Orthofotos and on digital elevation models. The results are presented in an Arc-Gis based geotechnical map. All mapped mass movements are stored in an Arc-Gis geodatabase and can be queried regarding properties, volume and controlling factors, so that statistical analyses can be conducted. The assessment of rock wall retreat rates is carried out by three different methods in multiple locations, which differ in altitude, exposition, lithology and deglaciation time: Firstly, rock fall processes and rates are investigated in detail on five rock fall collector nets with an overall size of 750 m2. Rock fall particles are gathered, weighed and grain size distribution is detected by sieving and measuring the diameter of the particles to distinct between rock fall processes and magnitudes. Rock wall erosion processes like joint formation and expansions are measured with high temporal resolution by electrical crack meters, together with rock- and air temperature. Secondly, in cooperation with the other working groups in the PROSA project, rock fall volumes are determined with multitemporal terrestrial laserscanning from several locations. Lately, already triggered rock falls are accounted by mapping the volume of the deposit and calculating of the bedrock source area. The deposition time span is fixed by consideration of the late Holocene lateral moraines and analysing historical aerial photographs, so that longer term rock wall retreat rates can be calculated. In order to limit

Changes in sitting posture induce multiplanar changes in chest wall shape and motion with breathing.

PubMed

Lee, Linda-Joy; Chang, Angela T; Coppieters, Michel W; Hodges, Paul W

2010-03-31

This study examined the effect of sitting posture on regional chest wall shape in three dimensions, chest wall motion (measured with electromagnetic motion analysis system), and relative contributions of the ribcage and abdomen to tidal volume (%RC/V(t)) (measured with inductance plethysmography) in 7 healthy volunteers. In seven seated postures, increased dead space breathing automatically increased V(t) (to 1.5 V(t)) to match volume between conditions and study the effects of posture independent of volume changes. %RC/V(t) (p<0.05), chest wall shape (p<0.05) and motion during breathing differed between postures. Compared to a reference posture, movement at the 9th rib lateral diameter increased in the thoracolumbar extension posture (p<0.008). In slumped posture movement at the AP diameters at T1 and axilla increased (p<0.00001). Rotation postures decreased movement in the lateral diameter at the axilla (p<0.0007). The data show that single plane changes in sitting posture alter three-dimensional ribcage configuration and chest wall kinematics during breathing, while maintaining constant respiratory function. Copyright 2010 Elsevier B.V. All rights reserved.

Large-area, electronically monodisperse, aligned single-walled carbon nanotube thin films fabricated by evaporation-driven self-assembly.

PubMed

Shastry, Tejas A; Seo, Jung-Woo T; Lopez, Josue J; Arnold, Heather N; Kelter, Jacob Z; Sangwan, Vinod K; Lauhon, Lincoln J; Marks, Tobin J; Hersam, Mark C

2013-01-14

By varying the evaporation conditions and the nanotube and surfactant concentrations, large-area, aligned single-walled carbon nanotube (SWCNT) thin films are fabricated from electronically monodisperse SWCNT solutions by evaporation-driven self-assembly with precise control over the thin film growth geometry. Tunability is possible from 0.5 μm stripes to continuous thin films. The resulting SWCNT thin films possess highly anisotropic electrical and optical properties that are well suited for transparent conductor applications. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Efficacy and problems of bladder volume measurement using portable three dimensional ultrasound scanning device--in particular, on measuring bladder volume lower than 100ml].

PubMed

Oh-Oka, Hitoshi; Nose, Ryuichiro

2005-09-01

Using a portable three dimensional ultrasound scanning device (The Bladder Scan BVI6100, Diagnostic Ultrasound Corporation), we examined measured values of bladder volume, especially focusing on volume lower than 100 ml. A total of 100 patients (male: 66, female: 34) were enrolled in the study. We made a comparison study between the measured value (the average of three measurements of bladder urine volume after a trial in male and female modes) using BVI6100, and the actual measured value of the sample obtained by urethral catheterization in each patient. We examined the factors which could increase the error rate. We also introduced the effective techniques to reduce measurement errors. The actual measured values in all patients correlated well with the average value of three measurements after a trial in a male mode of the BVI6100. The correlation coefficient was 0.887, the error rate was--4.6 +/- 24.5%, and the average coefficient of variation was 15.2. It was observed that the measurement result using the BVI6100 is influenced by patient side factors (extracted edges between bladder wall and urine, thickened bladder wall, irregular bladder wall, flattened rate of bladder, mistaking prostate for bladder in male, mistaking bladder for uterus in a female mode, etc.) or examiner side factors (angle between BVI and abdominal wall, compatibility between abdominal wall and ultrasound probe, controlling deflection while using probe, etc). When appropriate patients are chosen and proper measurement is performed, BVI6100 provides significantly higher accuracy in determining bladder volume, compared with existing abdominal ultrasound methods. BVI6100 is a convenient and extremely effective device also for the measurement of bladder urine over 100 ml.

A Fully Automated Supraglacial lake area and volume Tracking ("FAST") algorithm: development and application using MODIS imagery of West Greenland

NASA Astrophysics Data System (ADS)

Williamson, Andrew; Arnold, Neil; Banwell, Alison; Willis, Ian

2017-04-01

Supraglacial lakes (SGLs) on the Greenland Ice Sheet (GrIS) influence ice dynamics if draining rapidly by hydrofracture, which can occur in under 24 hours. MODerate-resolution Imaging Spectroradiometer (MODIS) data are often used to investigate SGLs, including calculating SGL area changes through time, but no existing work presents a method that tracks changes in individual (and total) SGL volume in MODIS imagery over a melt season. Here, we present such a method. First, we tested three automated approaches to derive SGL areas from MODIS imagery by comparing calculated areas for the Paakitsoq and Store Glacier regions in West Greenland with areas derived from Landsat-8 (LS8) images. Second, we applied a physically-based depth-calculation algorithm to the pixels within the SGL boundaries from the best performing method, and validated the resultant depths with those calculated using the same method applied to LS8 imagery. Our results indicated that SGL areas are most accurately generated using dynamic thresholding of MODIS band 1 (red) with a 0.640 threshold value. Calculated SGL area, depth and volume values from MODIS were closely comparable to those derived from LS8. The best performing area- and depth-detection methods were then incorporated into a Fully Automated SGL Tracking ("FAST") algorithm that tracks individual SGLs between successive MODIS images. It identified 43 (Paakitsoq) and 19 (Store Glacier) rapidly draining SGLs during 2014, representing 21% and 15% of the respective total SGL populations, including some clusters of rapidly draining SGLs. We found no relationship between the water volumes contained within these rapidly draining SGLs and the ice thicknesses beneath them, indicating that a critical water volume linearly related to ice thickness cannot explain the incidence of rapid drainage. The FAST algorithm, which we believe to be the most comprehensive SGL tracking algorithm developed to date, has the potential to investigate statistical

Stability analysis of wall driven nanofluid flow through a tube

NASA Astrophysics Data System (ADS)

Hossain, M. Mainul; Khan, M. A. H.

2017-06-01

Wall driven incompressible viscous fluid flow with nanoparticles through a tube is considered where two different nanofluids (Cu-water, SiO2-water) are used separately. Flow becomes gradually unstable due to movement of wall and existence of nanoparticles. However, Reynolds number, volume fraction and density ratio are responsible for flow instability. The mathematical model of the problem is constructed and solved by means of series solution method. Special type Hermite-Padé approximation method is used to improve the series solution. The critical point for Reynolds number, volume fraction and density ratio are determined and described using approximation technique and bifurcation diagram for both nanofluids. Moreover, Interaction between these three numbers and their effect on velocity profile are discussed. To indicate the nanofluid which is more effective for flow stability is our major concerned.

Enhanced delineation of degradation in aortic walls through OCT

NASA Astrophysics Data System (ADS)

Real, Eusebio; Val-Bernal, José Fernando; Revuelta, José M.; Pontón, Alejandro; Calvo Díez, Marta; Mayorga, Marta; López-Higuera, José M.; Conde, Olga M.

2015-03-01

Degradation of the wall of human ascending thoracic aorta has been assessed through Optical Coherence Tomography (OCT). OCT images of the media layer of the aortic wall exhibit micro-structure degradation in case of diseased aortas from aneurysmal vessels or in aortas prone to aortic dissections. The degeneration in vessel walls appears as low-reflectivity areas due to the invasive appearance of acidic polysaccharides and mucopolysaccharides within a typical ordered microstructure of parallel lamellae of smooth muscle cells, elastin and collagen fibers. An OCT indicator of wall degradation can be generated upon the spatial quantification of the extension of degraded areas in a similar way as conventional histopathology. This proposed OCT marker offers a real-time clinical insight of the vessel status to help cardiovascular surgeons in vessel repair interventions. However, the delineation of degraded areas on the B-scan image from OCT is sometimes difficult due to presence of speckle noise, variable SNR conditions on the measurement process, etc. Degraded areas could be outlined by basic thresholding techniques taking advantage of disorders evidences in B-scan images, but this delineation is not always optimum and requires complex additional processing stages. This work proposes an optimized delineation of degraded spots in vessel walls, robust to noisy environments, based on the analysis of the second order variation of image intensity of backreflection to determine the type of local structure. Results improve the delineation of wall anomalies providing a deeper physiological perception of the vessel wall conditions. Achievements could be also transferred to other clinical scenarios: carotid arteries, aorto-iliac or ilio-femoral sections, intracranial, etc.

Rain volume estimation over areas using satellite and radar data

NASA Technical Reports Server (NTRS)

Doneaud, A. A.; Vonderhaar, T. H.

1985-01-01

An investigation of the feasibility of rain volume estimation using satellite data following a technique recently developed with radar data called the Arera Time Integral was undertaken. Case studies were selected on the basis of existing radar and satellite data sets which match in space and time. Four multicell clusters were analyzed. Routines for navigation remapping amd smoothing of satellite images were performed. Visible counts were normalized for solar zenith angle. A radar sector of interest was defined to delineate specific radar echo clusters for each radar time throughout the radar echo cluster lifetime. A satellite sector of interest was defined by applying small adjustments to the radar sector using a manual processing technique. The radar echo area, the IR maximum counts and the IR counts matching radar echo areas were found to evolve similarly, except for the decaying phase of the cluster where the cirrus debris keeps the IR counts high.

Re-assessing Rainwater Harvesting Volume by CHIRPS Satellite in Semarang Settlement Area

NASA Astrophysics Data System (ADS)

Prihanto, Yosef; Koestoer, Raldi H.; Sutjiningsih, Dwita

2017-12-01

Semarang City is one of the most influential coastal cities in Java Island. The city is facing increasingly-high water demand due to its development and water problems due to climate change. The spatial physiography and landscape of Semarang City are also exposed the city to water security problem. Hence, rainwater harvesting treatment is an urgent effort to meet the city’s water needs. However, planning, implementation and management of rainwater harvesting are highly depended on multitemporal rainfall data. It has not yet been fully compiled due to limited rain stations. This study aims to examine the extent to which CHIRPS satellite data can be utilized in estimating volume of rainwater harvesting 16 sub-districts in Semarang and determine the water security status. This study uses descriptive statistical method based on spatial analyses. Such method was developed through spatial modeling for rainfall using isohyetal model. The parameters used are rainfall, residential rooftop area, administrative area, population, physiographic and altitude units. Validation is carried out by using monthly 10 rain stations data. The results show level of validity by utilizing CHIRPS Satellite data and mapping rainfall distribution. This study also produces a potential map of distribution rainfall volume that can be harvested in 16 sub-districts of Semarang.

Comparison of volume and surface area nonpolar solvation free energy terms for implicit solvent simulations.

PubMed

Lee, Michael S; Olson, Mark A

2013-07-28

Implicit solvent models for molecular dynamics simulations are often composed of polar and nonpolar terms. Typically, the nonpolar solvation free energy is approximated by the solvent-accessible-surface area times a constant factor. More sophisticated approaches incorporate an estimate of the attractive dispersion forces of the solvent and∕or a solvent-accessible volume cavitation term. In this work, we confirm that a single volume-based nonpolar term most closely fits the dispersion and cavitation forces obtained from benchmark explicit solvent simulations of fixed protein conformations. Next, we incorporated the volume term into molecular dynamics simulations and find the term is not universally suitable for folding up small proteins. We surmise that while mean-field cavitation terms such as volume and SASA often tilt the energy landscape towards native-like folds, they also may sporadically introduce bottlenecks into the folding pathway that hinder the progression towards the native state.

Comparison of volume and surface area nonpolar solvation free energy terms for implicit solvent simulations

NASA Astrophysics Data System (ADS)

Lee, Michael S.; Olson, Mark A.

2013-07-01

Implicit solvent models for molecular dynamics simulations are often composed of polar and nonpolar terms. Typically, the nonpolar solvation free energy is approximated by the solvent-accessible-surface area times a constant factor. More sophisticated approaches incorporate an estimate of the attractive dispersion forces of the solvent and/or a solvent-accessible volume cavitation term. In this work, we confirm that a single volume-based nonpolar term most closely fits the dispersion and cavitation forces obtained from benchmark explicit solvent simulations of fixed protein conformations. Next, we incorporated the volume term into molecular dynamics simulations and find the term is not universally suitable for folding up small proteins. We surmise that while mean-field cavitation terms such as volume and SASA often tilt the energy landscape towards native-like folds, they also may sporadically introduce bottlenecks into the folding pathway that hinder the progression towards the native state.

Endoscopic transnasal approach for the treatment of isolated medial orbital blow-out fractures: a prospective study of preoperative and postoperative orbital volume change.

PubMed

Kim, KyoungHoon; Song, KyeongHo; Choi, SooJong; Bae, YongChan; Choi, ChiWon; Oh, HeungChan; Lee, JaeWoo; Nam, SuBong

2012-02-01

Endoscopic transnasal reduction is a safe and effective technique for the treatment of blow-out fractures of the medial orbital wall. However, because this approach does not use rigid permanent material for reconstruction of the fractured medial orbital wall, some degree of herniation of the orbital contents may occur after the intraethmoidal packing material is removed. The purpose of this study was to evaluate the change in orbital volume in patients with medial orbital wall fractures treated through an endoscopic transnasal approach. This study was a prospective analysis that includes 20 patients who underwent endoscopic transnasal reduction of medial orbital wall fractures between April 2007 and December 2008. Computer-assisted orbital volume measurements were made using axial computed tomography. The mean (standard deviation [SD]) volume increase was 2.00 (0.92) cm(3) and the mean (SD) dimension of the fractured orbital wall was 2.76 (0.83) cm(2). After endoscopic surgery, an average (SD) volume decrease of 2.15 (0.91) cm(3) was achieved with ethmoid sinus packing. After removal of the packing materials, 1.14 (0.78) cm(3) increase of the orbital volume was observed. The dimension of the orbital wall fracture significantly correlated with the increased preoperative orbital volume (P = 0.002, r = 0.609); the preoperative increase in the orbital volume also significantly correlated with volume relapse after removal of the packing (P = 0.023, r = 0.452). These findings suggest that in broad orbital wall fractures, reconstruction of the orbital wall by rigid materials or prolongation of the packing period should be considered, because orbital volume can increase again after packing removal, and may thus lead to postoperative complications.

Archaeological Investigations in the Gainesville Lake Area of the Tennessee-Tombigbee Waterway. Volume I. The Gainesville Lake Area Excavations.

DTIC Science & Technology

1981-01-01

97 71. Site 1Pi61, Removing Trees ........ .................. . 97 72. Site lPi6l, Testing the Midden ....... ................ . 97 6...the use of plant and animal species changes through time. Volume IV also describes the human skeletal remains from all excavated sites and discusses the...Gainesville Lake area were cultural features. A few 5 features resulted from forces other than human behavior ( tree roots, ro- dent burrows, erosional gullies

Stabilization of endangered part of structures by building dry brunt brick buttressing, critical case study of plane wall in DKG-North Area, Mohenjo daro

NASA Astrophysics Data System (ADS)

Shaikh, J. M.; Park, J.

2013-07-01

'World Heritage Sites' are places or buildings of outstanding universal value recognized as constituting a world heritage 'for whose protection it is the duty of the international community as a whole to co-operate'. The concept of World Heritage is at the core of the World Heritage Convention, adopted by Heritage List as a means of identifying, protecting, conserving and presenting those parts of the world's natural and cultural heritage that are of sufficient 'outstanding universal value' to be the responsibility of the international community as a whole. By joining the Convention, nation states are pledged to safeguard the WH S by protecting their national heritage. UNESCO in 1972, to which 160 nations have now been adhered. The Convention came into force in 1975 and established a Site in their territory as part of a universally agreed policy for World. Moenjodaro site covering an area of 555 Acres out of which only 10 % of it has been excavated by exposing 50 Kilometer standing walls. The wall of the main street of DK G Area, Mohen jo Daro partially deformed, due to the torque effects this is studied here on a lateral cross wall in the chief house. Furthermore, the resulting behaviour of the bucking wall demonstrates the significant loadbearing capacity of the structure under service conditions and its high sensitivity to imposed changes of the geometry. Although the tensile stresses exceeded the flexural strength at the vertices and the length of the wall, hence both the geometry and condition of this area are critical for the safety of the wall. The results of this study can improve the assessment and thus help in the preservation of many important structures of the metropolitan city. Here the hydrous characteristic of the brick is studied as a general phenomenon, it is observed that the remains of the sites located in Sindh suffered a lot mostly due to age, human neglect variations of atmospheric condition, severe temperature and natural disasters. The main

Monitoring and modelling for dry-stone walls terracement maintenance

NASA Astrophysics Data System (ADS)

Preti, Federico; Errico, Alessandro; Giambastiani, Yamuna; Guastini, Enrico; Penna, Daniele

2017-04-01

An analysis of dry-stone walls stability in agricultural areas based on innovative monitoring and modeling is here presented The field test took place in Lamole, a terraced rural area located in the province of Florence, Tuscany, central Italy, where wine production is the most important agricultural activity business. Results show a good capability of the model to predict the time-space distribution and the intensity of stresses on the instrumented dry-stone wall and to describe the bulging of the ancient ones. We obtained significant information on how the terrace failure in Lamole resulted mainly related to the water concentration pathways at specific portions of the walls. An accurate drainage of the terraced slopes, even by means of simple ditches, could reduce the concentration factor at the critical parts of terraces strongly reducing the water pressures on the walls. The analysis of the effects caused by high return time events has been carried out by means of artificially reproduced severe rainfalls on the presented experimental area.

Vastus medialis cross-sectional area is positively associated with patella cartilage and bone volumes in a pain-free community-based population

PubMed Central

Berry, Patricia A; Teichtahl, Andrew J; Galevska-Dimitrovska, Ana; Hanna, Fahad S; Wluka, Anita E; Wang, Yuanyuan; Urquhart, Donna M; English, Dallas R; Giles, Graham G; Cicuttini, Flavia M

2008-01-01

Introduction Although vastus medialis and lateralis are important determinants of patellofemoral joint function, their relationship with patellofemoral joint structure is unknown. The aim of this study was to examine potential determinants of vastus medialis and lateralis cross-sectional areas and the relationship between the cross-sectional area and patella cartilage and bone volumes. Methods Two hundred ninety-seven healthy adult subjects had magnetic resonance imaging of their dominant knee. Vastus medialis and lateralis cross-sectional areas were measured 37.5 mm superior to the quadriceps tendon insertion at the proximal pole of the patella. Patella cartilage and bone volumes were measured from these images. Demographic data and participation in vigorous physical activity were assessed by questionnaire. Results The determinants of increased vastus medialis and lateralis cross-sectional areas were older age (P ≤ 0.002), male gender (P < 0.001), and greater body mass index (P ≤ 0.07). Participation in vigorous physical activity was positively associated with vastus medialis cross-sectional area (regression coefficient [beta] 90.0; 95% confidence interval [CI] 38.2, 141.7) (P < 0.001) but not with vastus lateralis cross-sectional area (beta 10.1; 95% CI -18.1, 38.3) (P = 0.48). The cross-sectional area of vastus medialis only was positively associated with patella cartilage volume (beta 0.6; 95% CI 0.23, 0.94) (P = 0.001) and bone volume (beta 3.0; 95% CI 1.40, 4.68) (P < 0.001) after adjustment for potential confounders. Conclusions Our results in a pain-free community-based population suggest that increased cross-sectional area of vastus medialis, which is associated with vigorous physical activity, and increased patella cartilage and bone volumes may benefit patellofemoral joint health and reduce the long-term risk of patellofemoral pathology. PMID:19077298

Thermal Performance Evaluation of Walls with Gas Filled Panel Insulation

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

Shrestha, Som S.; Desjarlais, Andre Omer; Atchley, Jerald Allen

Gas filled insulation panels (GFP) are very light weight and compact (when uninflated) advanced insulation products. GFPs consist of multiple layers of thin, low emittance (low-e) metalized aluminum. When expanded, the internal, low-e aluminum layers form a honeycomb structure. These baffled polymer chambers are enveloped by a sealed barrier and filled with either air or a low-conductivity gas. The sealed exterior aluminum foil barrier films provide thermal resistance, flammability protection, and properties to contain air or a low conductivity inert gas. This product was initially developed with a grant from the U.S. Department of Energy. The unexpanded product is nearlymore » flat for easy storage and transport. Therefore, transportation volume and weight of the GFP to fill unit volume of wall cavity is much smaller compared to that of other conventional insulation products. This feature makes this product appealing to use at Army Contingency Basing, when transportation cost is significant compared to the cost of materials. The objective of this study is to evaluate thermal performance of walls, similar to those used at typical Barracks Hut (B-Hut) hard shelters, when GFPs are used in the wall cavities. Oak Ridge National Laboratory (ORNL) tested performance of the wall in the rotatable guarded hotbox (RGHB) according to the ASTM C 1363 standard test method.« less

Time Resolved Tomographic PIV Measurements of Rough-Wall Turbulent Channel Flow

NASA Astrophysics Data System (ADS)

Miorini, Rinaldo; Zhang, Cao; Katz, Joseph

2013-11-01

Time resolved tomographic PIV is used to study flow structures in the outer region of a rough-wall turbulent boundary layer, focusing on imprints of the roughness on the outer layer. Measurements are performed in a transparent channel installed in the JHU optically index matched facility. The roughness consists of pyramids with height, k = 0.46 mm, and wavelength, λ = 3.2 mm, satisfying h/k = 55 (h = 25.4 mm is the channel half-height), k + = 64 and Re = 40000. The TPIV setup consists of four high-speed cameras operating at 3 kHz, which view the sample volume through acrylic prisms. The flow field is illuminated by an Nd:YLF laser. Following enhancement, calibration, and reconstruction, 643 voxels interrogation volumes with 0.75 overlap provide 3D velocity fields with spacing of 0.5883 mm3. Formation and transport of near-wall 3D U-shaped vortex structures, with base in front of the pyramids, and quasi-streamwise legs extending between pyramid crest lines are evident from the data. Extended streamwise regions of high wall-normal vorticity appear ``latched'' to the roughness elements close to the wall, but are transported downstream at higher elevations. Also evident are traveling streamwise low velocity streaks, which cover many roughness elements. Sponsored by NSF CBET and ONR.

Investigation of wall-bounded turbulence over regularly distributed roughness

NASA Astrophysics Data System (ADS)

Placidi, Marco; Ganapathisubramani, Bharathram

2012-11-01

The effects of regularly distributed roughness elements on the structure of a turbulent boundary layer are examined by performing a series of Planar (high resolution l+ ~ 30) and Stereoscopic Particle Image Velocimetry (PIV) experiments in a wind tunnel. An adequate description of how to best characterise a rough wall, especially one where the density of roughness elements is sparse, is yet to be developed. In this study, rough surfaces consisting of regularly and uniformly distributed LEGO® blocks are used. Twelve different patterns are adopted in order to systematically examine the effects of frontal solidity (λf, frontal area of the roughness elements per unit wall-parallel area) and plan solidity (λp, plan area of roughness elements per unit wall-parallel area), on the turbulence structure. The Karman number, Reτ , is approximately 4000 across the different cases. Spanwise 3D vector fields at two different wall-normal locations (top of the canopy and within the log-region) are also compared to examine the spanwise homogeneity of the flow across different surfaces. In the talk, a detailed analysis of mean and rms velocity profiles, Reynolds stresses, and quadrant decomposition for the different patterns will be presented.

Hierarchically Porous Graphitic Carbon with Simultaneously High Surface Area and Colossal Pore Volume Engineered via Ice Templating

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

Estevez, Luis; Prabhakaran, Venkateshkumar; Garcia, Adam L.

Developing hierarchical porous carbon (HPC) materials with competing textural characteristics such as surface area and pore volume in one material is difficult to accomplish—particulalry for an atomically ordered (graphitic) carbon. Herein we describe a synthesis strategy to engineer tunable hierarchically porous carbon (HPC) materials across micro- meso- and macroporous length scales, allowing the fabrication of a graphitic HPC with both very high surface area (> 2500 m2/g) and pore volume (>10 cm3/g), the combination of which has not been seen previously. The mesopore volume alone for these materials is up to 7.91 cm3/g, the highest ever reported. The unique materialmore » was explored for use as a supercapaictor electrode and for oil adsorption; two applications that require textural properties that are typicaly exclusive to one another. This design scheme for HPCs can be utilized in broad applications, including electrochemical systems such as batteries and supercapacitors, sorbents, and catalyst supports.« less

High performance discharges in the Lithium Tokamak eXperiment with liquid lithium walls

DOE PAGES

Schmitt, J. C.; Bell, R. E.; Boyle, D. P.; ...

2015-05-15

The first-ever successful operation of a tokamak with a large area (40% of the total plasma surface area) liquid lithium wall has been achieved in the Lithium Tokamak eXperiment (LTX). These results were obtained with a new, electron beam-based lithium evaporation system, which can deposit a lithium coating on the limiting wall of LTX in a five-minute period. Preliminary analyses of diamagnetic and other data for discharges operated with a liquid lithium wall indicate that confinement times increased by 10 x compared to discharges with helium-dispersed solid lithium coatings. Ohmic energy confinement times with fresh lithium walls, solid and liquid,more » exceed several relevant empirical scaling expressions. Spectroscopic analysis of the discharges indicates that oxygen levels in the discharges limited on liquid lithium walls were significantly reduced compared to discharges limited on solid lithium walls. Finally, Tokamak operations with a full liquid lithium wall (85% of the total plasma surface area) have recently started.« less

Implementing Green Walls in Schools.

PubMed

McCullough, Michael B; Martin, Michael D; Sajady, Mollika A

2018-01-01

Numerous studies in applied pedagogical design have shown that, at all educational levels, direct exposure to the natural environment can enhance learning by improving student attention and behaviors. Implementing green walls-a "vertical garden," or "living wall" interior wall that typically includes greenery, a growing medium (soil or substrate) and a water delivery system-provides environmental health benefits, but also provides a practical application within classrooms for minimizing directed attention fatigue in students by connecting them to "outdoor nature" within the indoor environment. Hands-on "project-based" learning is another pedagogical strategy that has proved to be effective across the spectrum of educational levels and across subject areas. Green walls have the potential to inspire critical thinking through a combination of project-based learning strategies and environmental education. The authors have outlined a curriculum involving the implementation of an indoor living wall system within a classroom-learning environment, incorporating project-based learning modules that interact with the wall. In conjunction with the passive health benefits of a green wall, project-based curriculum models can connect students interactively with indoor nature and have the potential to inspire real-world thinking related to science, technology, engineering, art, and mathematics fields within the indoor learning environment. Through a combination of these passive and interactive modes, students are connected to nature in the indoor environment regardless of weather conditions outdoors. Future research direction could include post-construction studies of the effectiveness of project-based curricula related to living walls, and the long-term impacts of implementing green walls in classrooms on school achievement and student behaviors.

Proportional Reasoning Ability and Concepts of Scale: Surface Area to Volume Relationships in Science

ERIC Educational Resources Information Center

Taylor, Amy; Jones, Gail

2009-01-01

The "National Science Education Standards" emphasise teaching unifying concepts and processes such as basic functions of living organisms, the living environment, and scale. Scale influences science processes and phenomena across the domains. One of the big ideas of scale is that of surface area to volume. This study explored whether or not there…

Recent Changes in Glacial Area and Volume on Tuanjiefeng Peak Region of Qilian Mountains, China

PubMed Central

Xu, Junli; Liu, Shiyin; Zhang, Shiqiang; Guo, Wanqin; Wang, Jian

2013-01-01

Glaciers' runoff in the Qilian Mountains serves as a critical water resource in the northern sections of the Gansu province, the northeastern sections of the Qinghai province, and the northeastern fringe of the Tibetan Plateau. Changes in the glacial area and volume around the highest peak of the Qilian Mountains, i.e., Tuanjiefeng Peak, were estimated using multi-temporal remote-sensing images and digital elevation models, and all possible sources of uncertainty were considered in detail. The total glacier area decreased by 16.1±6.34 km2 (9.9±3.9%) during 1966 to 2010. The average annual glacier shrinkage was −0.15% a−1 from 1966 to 1995, −0.61% a−1 from 1995 to 2000, −0.20% a−1 from 2000 to 2006, and −0.45% a−1 from 2006 to 2010. A comparison of glacier surface elevations using digital elevation models derived from topographic maps in 1966 and from the Shuttle Radar Topography Mission in 1999 suggests that 65% of the grid cells has decreased, thereby indicating that the glacier thickness has declined. The average change in glacier thickness was −7.3±1.5 m (−0.21±0.04 m·a−1) from 1966 to 1999. Glaciers with northeastern aspects thinned by 8.3±1.4 m from 1966 to 1999, i.e., almost twice as much as those with southwestern aspects (4.3±1.3 m). The ice volume decreased by 11.72±2.38×108 m3 from 1966 to 1999, which was about 17.4% more than the value calculated from the statistical relationship between glacier area and volume. The relationship between glacier area change and elevation zone indicates that glacier change is not only dominated by climate change but also affected by glacier dynamics, which are related to local topography. The varied response of a single glacier to climate change indicates that the glacier area change scheme used in some models must be improved. PMID:24015174

Thoracic wall trauma—misdiagnosed lesions on radiographs and usefulness of ultrasound, multidetector computed tomography and magnetic resonance imaging

PubMed Central

Facenda, Catherine; Vaz, Nuno; Castañeda, Edgar Augusto; del Amo, Montserrat; Garcia-Diez, Ana Isabel; Pomes, Jaime

2017-01-01

Blunt injuries to the chest wall are an important chapter on emergency room (ER) departments, being the third most common injuries in trauma patients which ominous complications could appear. This article describes different types of traumatic events affecting the chest wall, which maybe misdiagnosed with conventional X-ray. Special emphasis has been done in computed tomography (CT) and multidetector CT (MDCT) imaging. This technique is considered the “gold-standard” for those traumatic patients, due to its fast acquisition covering the whole area of interest in axial plane, reconstructing multiplanar (2D, 3D) volume-rendered images with a superb quality and angiographic CT capabilities for evaluating vascular damage. Complementary techniques such as ultrasonography (US) and magnetic resonance imaging (MRI) may improve the diagnostic accuracy due to its great capacity in visualising soft-tissue trauma (muscle-tendinous tears) and subtle fractures. All these imaging methods have an important role in quantifying the severity of chest wall trauma. The findings of this study have been exposed with cases of our archives in a didactic way. PMID:28932697

Regeneration of near-wall turbulence structures

NASA Technical Reports Server (NTRS)

Hamilton, James M.; Kim, John J.; Waleffe, Fabian A.

1993-01-01

An examination of the regeneration mechanisms of near-wall turbulence and an attempt to investigate the critical Reynolds number conjecture of Waleffe & Kim is presented. The basis is an extension of the 'minimal channel' approach of Jimenez and Moin which emphasizes the near-wall region and further reduces the complexity of the turbulent flow. Reduction of the flow Reynolds number to the minimum value which will allow turbulence to be sustained has the effect of reducing the ratio of the largest scales to the smallest scales or, equivalently, of causing the near-wall region to fill more of the area between the channel walls. In addition, since each wall may have an active near-wall region, half of the channel is always somewhat redundant. If a plane Couette flow is instead chosen as the base flow, this redundancy is eliminated: the mean shear of a plane Couette flow has a single sign, and at low Reynolds numbers, the two wall regions share a single set of structures. A minimal flow with these modifications possesses, by construction, the strongest constraints which allow sustained turbulence, producing a greatly simplified flow in which the regeneration process can be examined.

Estimation of Effective Directional Strength of Single Walled Wavy CNT Reinforced Nanocomposite

NASA Astrophysics Data System (ADS)

Bhowmik, Krishnendu; Kumar, Pranav; Khutia, Niloy; Chowdhury, Amit Roy

2018-03-01

In this present work, single walled wavy carbon nanotube reinforced into composite has been studied to predict the effective directional strength of the nanocomposite. The effect of waviness on the overall Young’s modulus of the composite has been analysed using three dimensional finite element model. Waviness pattern of carbon nanotube is considered as periodic cosine function. Both long (continuous) and short (discontinuous) carbon nanotubes are being idealized as solid annular tube. Short carbon nanotube is modelled with hemispherical cap at its both ends. Representative Volume Element models have been developed with different waviness, height fractions, volume fractions and modulus ratios of carbon nanotubes. Consequently a micromechanics based analytical model has been formulated to derive the effective reinforcing modulus of wavy carbon nanotubes. In these models wavy single walled wavy carbon nanotubes are considered to be aligned along the longitudinal axis of the Representative Volume Element model. Results obtained from finite element analyses are compared with analytical model and they are found in good agreement.

The effect of wall thickness distribution on mechanical reliability and strength in unidirectional porous ceramics.

PubMed

Seuba, Jordi; Deville, Sylvain; Guizard, Christian; Stevenson, Adam J

2016-01-01

Macroporous ceramics exhibit an intrinsic strength variability caused by the random distribution of defects in their structure. However, the precise role of microstructural features, other than pore volume, on reliability is still unknown. Here, we analyze the applicability of the Weibull analysis to unidirectional macroporous yttria-stabilized-zirconia (YSZ) prepared by ice-templating. First, we performed crush tests on samples with controlled microstructural features with the loading direction parallel to the porosity. The compressive strength data were fitted using two different fitting techniques, ordinary least squares and Bayesian Markov Chain Monte Carlo, to evaluate whether Weibull statistics are an adequate descriptor of the strength distribution. The statistical descriptors indicated that the strength data are well described by the Weibull statistical approach, for both fitting methods used. Furthermore, we assess the effect of different microstructural features (volume, size, densification of the walls, and morphology) on Weibull modulus and strength. We found that the key microstructural parameter controlling reliability is wall thickness. In contrast, pore volume is the main parameter controlling the strength. The highest Weibull modulus ([Formula: see text]) and mean strength (198.2 MPa) were obtained for the samples with the smallest and narrowest wall thickness distribution (3.1 [Formula: see text]m) and lower pore volume (54.5%).

The effect of wall thickness distribution on mechanical reliability and strength in unidirectional porous ceramics

NASA Astrophysics Data System (ADS)

Seuba, Jordi; Deville, Sylvain; Guizard, Christian; Stevenson, Adam J.

2016-01-01

Macroporous ceramics exhibit an intrinsic strength variability caused by the random distribution of defects in their structure. However, the precise role of microstructural features, other than pore volume, on reliability is still unknown. Here, we analyze the applicability of the Weibull analysis to unidirectional macroporous yttria-stabilized-zirconia (YSZ) prepared by ice-templating. First, we performed crush tests on samples with controlled microstructural features with the loading direction parallel to the porosity. The compressive strength data were fitted using two different fitting techniques, ordinary least squares and Bayesian Markov Chain Monte Carlo, to evaluate whether Weibull statistics are an adequate descriptor of the strength distribution. The statistical descriptors indicated that the strength data are well described by the Weibull statistical approach, for both fitting methods used. Furthermore, we assess the effect of different microstructural features (volume, size, densification of the walls, and morphology) on Weibull modulus and strength. We found that the key microstructural parameter controlling reliability is wall thickness. In contrast, pore volume is the main parameter controlling the strength. The highest Weibull modulus (?) and mean strength (198.2 MPa) were obtained for the samples with the smallest and narrowest wall thickness distribution (3.1 ?m) and lower pore volume (54.5%).

A Charged Particle Veto Wall for the Large Area Neutron Array (LANA)

NASA Astrophysics Data System (ADS)

Zhu, K.; Chajecki, Z.; Anderson, C.; Bromell, J.; Brown, K.; Crosby, J.; Kodali, S.; Lynch, W. G.; Morfouace, P.; Sweany, S.; Tsang, M. B.; Tsang, C.; Brett, J. J.; Swaim, J. L.

2017-09-01

Comparison of neutrons and protons emitted in heavy ion collisions is one of the observables to probe symmetry energy, which is related to the properties of neutron star. In general, neutrons are difficult to measure and neutron detectors are not as easy to use or as widely available as charged particle detectors. Two neutron walls (NW) called LANA exist at the National Superconducting Cyclotron Laboratory. Although the NSCL NW attains excellent discrimination of γ rays and neutron, it fails to discriminate charged particles from neutrons. To ensure near 100% rejection of charged particles, a Charged Particle Veto Wall (VW) is being jointly built by Michigan State University and Western Michigan University. It will be placed in front of one NW. To increase efficiency in detecting neutrons, the second neutron wall is stacked behind it. In this presentation, I will discuss the design, construction and testing of the VW together with the LANA in preparation of two approved NSCL experiments to probe the density and momentum dependence of the symmetry energy potentials in the equation state of the asymmetric nuclear matter. This material is based upon work supported by the National Science Foundation under Grant No. PHY 1565546.

Three-component borehole wall-locking seismic detector

DOEpatents

Owen, Thomas E.

1994-01-01

A seismic detector for boreholes is described that has an accelerometer sensor block for sensing vibrations in geologic formations of the earth. The density of the seismic detector is approximately matched to the density of the formations in which the detector is utilized. A simple compass is used to orient the seismic detector. A large surface area shoe having a radius approximately equal to the radius of the borehole in which the seismic detector is located may be pushed against the side of the borehole by actuating cylinders contained in the seismic detector. Hydraulic drive of the cylinders is provided external to the detector. By using the large surface area wall-locking shoe, force holding the seismic detector in place is distributed over a larger area of the borehole wall thereby eliminating concentrated stresses. Borehole wall-locking forces up to ten times the weight of the seismic detector can be applied thereby ensuring maximum detection frequency response up to 2,000 hertz using accelerometer sensors in a triaxial array within the seismic detector.

Characterization of the intragranular water regime within subsurface sediments: Pore volume, surface area, and mass transfer limitations

USGS Publications Warehouse

Hay, M.B.; Stoliker, D.L.; Davis, J.A.; Zachara, J.M.

2011-01-01

Although "intragranular" pore space within grain aggregates, grain fractures, and mineral surface coatings may contain a relatively small fraction of the total porosity within a porous medium, it often contains a significant fraction of the reactive surface area, and can thus strongly affect the transport of sorbing solutes. In this work, we demonstrate a batch experiment procedure using tritiated water as a high-resolution diffusive tracer to characterize the intragranular pore space. The method was tested using uranium-contaminated sediments from the vadose and capillary fringe zones beneath the former 300A process ponds at the Hanford site (Washington). Sediments were contacted with tracers in artificial groundwater, followed by a replacement of bulk solution with tracer-free groundwater and the monitoring of tracer release. From these data, intragranular pore volumes were calculated and mass transfer rates were quantified using a multirate first-order mass transfer model. Tritium-hydrogen exchange on surface hydroxyls was accounted for by conducting additional tracer experiments on sediment that was vacuum dried after reaction. The complementary ("wet" and "dry") techniques allowed for the simultaneous determination of intragranular porosity and surface area using tritium. The Hanford 300A samples exhibited intragranular pore volumes of ???1% of the solid volume and intragranular surface areas of ???20%-35% of the total surface area. Analogous experiments using bromide ion as a tracer yielded very different results, suggesting very little penetration of bromide into the intragranular porosity. Copyright 2011 by the American Geophysical Union.

Characterization of the intragranular water regime within subsurface sediments: pore volume, surface area, and mass transfer limitations

USGS Publications Warehouse

Hay, Michael B.; Stoliker, Deborah L.; Davis, James A.; Zachara, John M.

2011-01-01

Although "intragranular" pore space within grain aggregates, grain fractures, and mineral surface coatings may contain a relatively small fraction of the total porosity within a porous medium, it often contains a significant fraction of the reactive surface area, and can thus strongly affect the transport of sorbing solutes. In this work, we demonstrate a batch experiment procedure using tritiated water as a high-resolution diffusive tracer to characterize the intragranular pore space. The method was tested using uranium-contaminated sediments from the vadose and capillary fringe zones beneath the former 300A process ponds at the Hanford site (Washington). Sediments were contacted with tracers in artificial groundwater, followed by a replacement of bulk solution with tracer-free groundwater and the monitoring of tracer release. From these data, intragranular pore volumes were calculated and mass transfer rates were quantified using a multirate first-order mass transfer model. Tritium-hydrogen exchange on surface hydroxyls was accounted for by conducting additional tracer experiments on sediment that was vacuum dried after reaction. The complementary ("wet" and "dry") techniques allowed for the simultaneous determination of intragranular porosity and surface area using tritium. The Hanford 300A samples exhibited intragranular pore volumes of ~1% of the solid volume and intragranular surface areas of ~20%–35% of the total surface area. Analogous experiments using bromide ion as a tracer yielded very different results, suggesting very little penetration of bromide into the intragranular porosity.

Investigation of wall-bounded turbulence over sparsely distributed roughness

NASA Astrophysics Data System (ADS)

Placidi, Marco; Ganapathisubramani, Bharath

2011-11-01

The effects of sparsely distributed roughness elements on the structure of a turbulent boundary layer are examined by performing a series of Particle Image Velocimetry (PIV) experiments in a wind tunnel. From the literature, the best way to characterise a rough wall, especially one where the density of roughness elements is sparse, is unclear. In this study, rough surfaces consisting of sparsely and uniformly distributed LEGO® blocks are used. Five different patterns are adopted in order to examine the effects of frontal solidity (λf, frontal area of the roughness elements per unit wall-parallel area), plan solidity (λp, plan area of roughness elements per unit wall-parallel area) and the geometry of the roughness element (square and cylindrical elements), on the turbulence structure. The Karman number, Reτ , has been matched, at the value of approximately 2300, in order to compare across the different cases. In the talk, we will present detailed analysis of mean and rms velocity profiles, Reynolds stresses and quadrant decomposition.

Modular first wall concept for steady state operation

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

Kotzlowski, H.E.

1981-01-01

On the basis of the limiter design proposed for ZEPHYR a first wall concept has been developed which can also be used as a large area limiter, heat shield or beam pump. Its specific feature is the thermal contact of the wall armour elements with the water-cooled base plates. The combination of radiation and contact cooling, compared with radiation only, helps to lower the steady state temperatures of the first wall by approximately 50 % and to reduce the cooling-time between discharges. Particulary the lower wall temperature give a larger margin for additional heating of the wall by plasma disruptionmore » or neutral beams until excessive erosion or damage of the armour takes place.« less

Dosimetric evaluation of integrated IMRT treatment of the chest wall and supraclavicular region for breast cancer after modified radical mastectomy

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

Yang, Bo; Wei, Xian-ding; Zhao, Yu-tian

2014-07-01

To investigate the dosimetric characteristics of irradiation of the chest wall and supraclavicular region as an integrated volume with intensity-modulated radiation therapy (IMRT) after modified radical mastectomy. This study included 246 patients who received modified radical mastectomy. The patients were scanned with computed tomography, and the chest wall (with or without the internal mammary lymph nodes) and supraclavicular region were delineated. For 143 patients, the chest wall and supraclavicular region were combined as an integrated planning volume and treated with IMRT. For 103 patients, conventional treatments were employed with 2 tangential fields for the chest wall, abutting a mixed fieldmore » of 6-MV x-rays (16 Gy) and 9-MeV electrons (34 Gy) for the upper supraclavicular region. The common prescription dose was 50 Gy/25 Fx/5 W to 90% of the target volume. The dosimetric characteristics of the chest wall, the supraclavicular region, and normal organs were compared. For the chest wall target, compared with conventional treatments, the integrated IMRT plans lowered the maximum dose, increased the minimum dose, and resulted in better conformity and uniformity of the target volume. There was an increase in minimum, average, and 95% prescription dose for the integrated IMRT plans in the supraclavicular region, and conformity and uniformity were improved. The V{sub 30} of the ipsilateral lung and V{sub 10}, V{sub 30}, and mean dose of the heart on the integrated IMRT plans were lower than those of the conventional plans. The V{sub 5} and V{sub 10} of the ipsilateral lung and V{sub 5} of the heart were higher on the integrated IMRT plans (p < 0.05) than on conventional plans. Without an increase in the radiation dose to organs at risk, the integrated IMRT treatment plans improved the dose distribution of the supraclavicular region and showed better dose conformity and uniformity of the integrated target volume of the chest wall and supraclavicular region.« less

Inspiratory flow rate, not type of incentive spirometry device, influences chest wall motion in healthy individuals.

PubMed

Chang, Angela T; Palmer, Kerry R; McNaught, Jessie; Thomas, Peter J

2010-08-01

This study investigated the effect of flow rates and spirometer type on chest wall motion in healthy individuals. Twenty-one healthy volunteers completed breathing trials to either two times tidal volume (2xV(T)) or inspiratory capacity (IC) at high, low, or natural flow rates, using a volume- or flow-oriented spirometer. The proportions of rib cage movement to tidal volume (%RC/V(T)), chest wall diameters, and perceived level of exertion (RPE) were compared. Low and natural flow rates resulted in significantly lower %RC/V(T) compared to high flow rate trials (p=0.001) at 2xV(T). Low flow trials also resulted in significantly less chest wall motion in the upper anteroposterior direction than high and natural flow rates (p<0.001). At IC, significantly greater movement occurred in the abdominal lateral direction during low flow compared to high and natural flow trials (both p<0.003). RPE was lower for the low flow trials compared to high flow trials at IC and 2xV(T) (p<0.01). In healthy individuals, inspiratory flow (not device type) during incentive spirometry determines the resultant breathing pattern. High flow rates result in greater chest wall motion than low flow rates.

Applications of Green Walls in Urban Design

NASA Astrophysics Data System (ADS)

Virtudes, Ana; Manso, Maria

2016-10-01

Green walls are a choice towards achieving sustainable urban rehabilitation, due to the lack of free space in the consolidated urban fabric. Nowadays, green walls are considered to be an innovation in the fields of ecology, horticulture or buildings. Nevertheless, in the domain of urban design, they are still surprising and unexpected ideas. Thus, this research aims to reflect on green walls as a feature in urban design and rehabilitation, identifying the advantages of their utilization as an enhancement of the quality of city's image, especially in dense urban areas. It aims to demonstrate some practical applications of green walls in urban design proposals, showing model solutions and their real application in several architectural examples.

Equilibrium Wall Model Implementation in a Nodal Finite Element Flow Solver JENRE for Large Eddy Simulations

DTIC Science & Technology

2017-11-13

condition is applied to the inviscid and viscous fluxes on the wall to satisfy the surface physical condition, but a non -zero surface tangential...velocity profiles and turbulence quantities predicted by the current wall-model implementation agree well with available experimental data and...implementations. The volume and surface integrals based on the non -zero surface velocity in a cell adjacent to the wall show a good agreement with those

Transcript Profiling Identifies NAC-Domain Genes Involved in Regulating Wall Ingrowth Deposition in Phloem Parenchyma Transfer Cells of Arabidopsis thaliana

PubMed Central

Wu, Yuzhou; Hou, Jiexi; Yu, Fen; Nguyen, Suong T. T.; McCurdy, David W.

2018-01-01

Transfer cells (TCs) play important roles in facilitating enhanced rates of nutrient transport at key apoplasmic/symplasmic junctions along the nutrient acquisition and transport pathways in plants. TCs achieve this capacity by developing elaborate wall ingrowth networks which serve to increase plasma membrane surface area thus increasing the cell's surface area-to-volume ratio to achieve increased flux of nutrients across the plasma membrane. Phloem parenchyma (PP) cells of Arabidopsis leaf veins trans-differentiate to become PP TCs which likely function in a two-step phloem loading mechanism by facilitating unloading of photoassimilates into the apoplasm for subsequent energy-dependent uptake into the sieve element/companion cell (SE/CC) complex. We are using PP TCs in Arabidopsis as a genetic model to identify transcription factors involved in coordinating deposition of the wall ingrowth network. Confocal imaging of pseudo-Schiff propidium iodide-stained tissue revealed different profiles of temporal development of wall ingrowth deposition across maturing cotyledons and juvenile leaves, and a basipetal gradient of deposition across mature adult leaves. RNA-Seq analysis was undertaken to identify differentially expressed genes common to these three different profiles of wall ingrowth deposition. This analysis identified 68 transcription factors up-regulated two-fold or more in at least two of the three experimental comparisons, with six of these transcription factors belonging to Clade III of the NAC-domain family. Phenotypic analysis of these NAC genes using insertional mutants revealed significant reductions in levels of wall ingrowth deposition, particularly in a double mutant of NAC056 and NAC018, as well as compromised sucrose-dependent root growth, indicating impaired capacity for phloem loading. Collectively, these results support the proposition that Clade III members of the NAC-domain family in Arabidopsis play important roles in regulating wall ingrowth

Transcript Profiling Identifies NAC-Domain Genes Involved in Regulating Wall Ingrowth Deposition in Phloem Parenchyma Transfer Cells of Arabidopsis thaliana.

PubMed

Wu, Yuzhou; Hou, Jiexi; Yu, Fen; Nguyen, Suong T T; McCurdy, David W

2018-01-01

Transfer cells (TCs) play important roles in facilitating enhanced rates of nutrient transport at key apoplasmic/symplasmic junctions along the nutrient acquisition and transport pathways in plants. TCs achieve this capacity by developing elaborate wall ingrowth networks which serve to increase plasma membrane surface area thus increasing the cell's surface area-to-volume ratio to achieve increased flux of nutrients across the plasma membrane. Phloem parenchyma (PP) cells of Arabidopsis leaf veins trans -differentiate to become PP TCs which likely function in a two-step phloem loading mechanism by facilitating unloading of photoassimilates into the apoplasm for subsequent energy-dependent uptake into the sieve element/companion cell (SE/CC) complex. We are using PP TCs in Arabidopsis as a genetic model to identify transcription factors involved in coordinating deposition of the wall ingrowth network. Confocal imaging of pseudo-Schiff propidium iodide-stained tissue revealed different profiles of temporal development of wall ingrowth deposition across maturing cotyledons and juvenile leaves, and a basipetal gradient of deposition across mature adult leaves. RNA-Seq analysis was undertaken to identify differentially expressed genes common to these three different profiles of wall ingrowth deposition. This analysis identified 68 transcription factors up-regulated two-fold or more in at least two of the three experimental comparisons, with six of these transcription factors belonging to Clade III of the NAC-domain family. Phenotypic analysis of these NAC genes using insertional mutants revealed significant reductions in levels of wall ingrowth deposition, particularly in a double mutant of NAC056 and NAC018 , as well as compromised sucrose-dependent root growth, indicating impaired capacity for phloem loading. Collectively, these results support the proposition that Clade III members of the NAC-domain family in Arabidopsis play important roles in regulating wall

L-arginine and glycine supplementation in the repair of the irradiated colonic wall of rats.

PubMed

de Aguiar Picanço, Etiene; Lopes-Paulo, Francisco; Marques, Ruy G; Diestel, Cristina F; Caetano, Carlos Eduardo R; de Souza, Mônica Vieira Mano; Moscoso, Gabriela Mendes; Pazos, Helena Maria F

2011-05-01

Radiotherapy is widely used for cancer treatment but has harmful effects. This study aimed to assess the effects of L-arginine and glycine supplementation on the colon wall of rats submitted to abdominal irradiation. Forty male Wistar rats were randomly divided into four groups: I-healthy, II-irradiated with no amino acid supplementation, III-irradiated and supplemented with L-arginine, and IV-irradiated and supplemented with glycine. The animals received supplementation for 14 days, with irradiation being applied on the eighth day of the experiment. All animals underwent laparotomy on the 15th day for resection of a colonic segment for stereologic analysis. Parametric and nonparametric tests were used for statistical analysis, with the level of significance set at p ≤0.05. Stereologic analysis showed that irradiation induced a reduction of the total volume of the colon wall of group II and III animals compared to healthy controls, but not of group IV animals supplemented with glycine. The mucosal layer of the irradiated animals of all groups was reduced compared to healthy group I animals, but supplementation with L-arginine and glycine was effective in maintaining the epithelial surface of the mucosal layer. The present results suggest that glycine supplementation had a superior effect on the irradiated colon wall compared to L-arginine supplementation since it was able to maintain the thickness of the wall and the epithelial surface of the mucosa, whereas L-arginine maintained the partial volume of the epithelium and the epithelial surface, but not the total volume of the intestinal wall.

Intra-Abdominal Hypertension and Abdominal Compartment Syndrome after Abdominal Wall Reconstruction: Quaternary Syndromes?

PubMed

Kirkpatrick, A W; Nickerson, D; Roberts, D J; Rosen, M J; McBeth, P B; Petro, C C; Berrevoet, Frederik; Sugrue, M; Xiao, Jimmy; Ball, C G

2017-06-01

Reconstruction with reconstitution of the container function of the abdominal compartment is increasingly being performed in patients with massive ventral hernia previously deemed inoperable. This situation places patients at great risk of severe intra-abdominal hypertension and abdominal compartment syndrome if organ failure ensues. Intra-abdominal hypertension and especially abdominal compartment syndrome may be devastating systemic complications with systematic and progressive organ failure and death. We thus reviewed the pathophysiology and reported clinical experiences with abnormalities of intra-abdominal pressure in the context of abdominal wall reconstruction. Bibliographic databases (1950-2015), websites, textbooks, and the bibliographies of previously recovered articles for reports or data relating to intra-abdominal pressure, intra-abdominal hypertension, and the abdominal compartment syndrome in relation to ventral, incisional, or abdominal hernia repair or abdominal wall reconstruction. Surgeons should thus consider and carefully measure intra-abdominal pressure and its resultant effects on respiratory parameters and function during abdominal wall reconstruction. The intra-abdominal pressure post-operatively will be a result of the new intra-peritoneal volume and the abdominal wall compliance. Strategies surgeons may utilize to ameliorate intra-abdominal pressure rise after abdominal wall reconstruction including temporizing paralysis of the musculature either temporarily or semi-permanently, pre-operative progressive pneumoperitoneum, permanently removing visceral contents, or surgically releasing the musculature to increase the abdominal container volume. In patients without complicating shock and inflammation, and in whom the abdominal wall anatomy has been so functionally adapted to maximize compliance, intra-abdominal hypertension may be transient and tolerable. Intra-abdominal hypertension/abdominal compartment syndrome in the specific setting of

Ethnomathematics study: uncovering units of length, area, and volume in Kampung Naga Society

NASA Astrophysics Data System (ADS)

Septianawati, T.; Turmudi; Puspita, E.

2017-02-01

During this time, mathematics is considered as something neutral and not associated with culture. It can be seen from mathematics learning in the school which adopt many of foreign mathematics learning are considered more advanced (western). In fact, Indonesia is a rich country in cultural diversity. In the cultural activities, there are mathematical ideas that were considered a important thing in the mathematics learning. A study that examines the idea or mathematical practices in a variety of cultural activities are known as ethnomathematics. In Indonesia, there are some ethnic maintain their ancestral traditions, one of them is Kampung Naga. Therefore, this study was conducted in Kampung Naga. This study aims to uncover units of length, area, and volume used by Kampung Naga society. This study used a qualitative approach and ethnography methods. In this research, data collection is done through the principles of ethnography such as observation, interviews, documentation, and field notes. The results of this study are units of length, area, and volume used by Kampung Naga society and its conversion into standard units. This research is expected to give information to the public that mathematics has a relationship with culture and become recommendation to mathematics curriculum in Indonesia.

A Near-Wall Reynolds-Stress Closure Without Wall Normals

NASA Technical Reports Server (NTRS)

Yuan, S. P.; So, R. M. C.

1997-01-01

Turbulent wall-bounded complex flows are commonly encountered in engineering practice and are of considerable interest in a variety of industrial applications. The presence of a wall significantly affects turbulence characteristics. In addition to the wall effects, turbulent wall-bounded flows become more complicated by the presence of additional body forces (e.g. centrifugal force and Coriolis force) and complex geometry. Most near-wall Reynolds stress models are developed from a high-Reynolds-number model which assumes turbulence is homogenous (or quasi-homogenous). Near-wall modifications are proposed to include wall effects in near-wall regions. In this process, wall normals are introduced. Good predictions could be obtained by Reynolds stress models with wall normals. However, ambiguity arises when the models are applied in flows with multiple walls. Many models have been proposed to model turbulent flows. Among them, Reynolds stress models, in which turbulent stresses are obtained by solving the Reynolds stress transport equations, have been proved to be the most successful ones. To apply the Reynolds stress models to wall-bounded flows, near-wall corrections accounting for the wall effects are needed, and the resulting models are called near-wall Reynolds stress models. In most of the existing near-wall models, the near-wall corrections invoke wall normals. These wall-dependent near-wall models are difficult to implement for turbulent flows with complex geometry and may give inaccurate predictions due to the ambiguity of wall normals at corners connecting multiple walls. The objective of this study is to develop a more general and flexible near-wall Reynolds stress model without using any wall-dependent variable for wall-bounded turbulent flows. With the aid of near-wall asymptotic analysis and results of direct numerical simulation, a new near-wall Reynolds stress model (NNWRS) is formulated based on Speziale et al.'s high-Reynolds-stress model with wall

3D cardiac wall thickening assessment for acute myocardial infarction

NASA Astrophysics Data System (ADS)

Khalid, A.; Chan, B. T.; Lim, E.; Liew, Y. M.

2017-06-01

Acute myocardial infarction (AMI) is the most severe form of coronary artery disease leading to localized myocardial injury and therefore irregularities in the cardiac wall contractility. Studies have found very limited differences in global indices (such as ejection fraction, myocardial mass and volume) between healthy subjects and AMI patients, and therefore suggested regional assessment. Regional index, specifically cardiac wall thickness (WT) and thickening is closely related to cardiac function and could reveal regional abnormality due to AMI. In this study, we developed a 3D wall thickening assessment method to identify regional wall contractility dysfunction due to localized myocardial injury from infarction. Wall thickness and thickening were assessed from 3D personalized cardiac models reconstructed from cine MRI images by fitting inscribed sphere between endocardial and epicardial wall. The thickening analysis was performed in 5 patients and 3 healthy subjects and the results were compared against the gold standard 2D late-gadolinium-enhanced (LGE) images for infarct localization. The notable finding of this study is the highly accurate estimation and visual representation of the infarct size and location in 3D. This study provides clinicians with an intuitive way to visually and qualitatively assess regional cardiac wall dysfunction due to infarction in AMI patients.

Sex determination using discriminant analysis of upper and lower extremity bones: New approach using the volume and surface area of digital model.

PubMed

Lee, U-Young; Kim, In-Beom; Kwak, Dai-Soon

2015-08-01

This study used 110 CT images taken from donated Korean cadavers to create 3-D models of the following upper and lower limb bones: the clavicle, scapula, humerus, radius, ulna, hip bone (os coxa), femur, patella (knee cap), tibia, talus, and calcaneus. In addition, the bone volume and surface area were calculated to determine sex differences using discriminant analysis. Significant sex differences were found in all bones with respect to volume and surface area (p<0.01). The order of volume was the same in females and males (femur>hip bone>tibia>humerus>scapula), although the order of surface area was different. The largest surface area in men was the femur and in women was the hip bone (p<0.01). An interesting finding of this study was that the ulna is the bone with the highest accuracy for sex determination (94%). When using the surface area of multiple bones, the maximum accuracy (99.4%) was achieved. The equation was as follows: (discriminant equation of surface area; female<0volume and surface area of extremity bones can be used for sex determination. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Volumes of recent floods and potential for storage in upland watershed areas of Iowa

USGS Publications Warehouse

Buchmiller, Robert C.; Eash, David A.; Harvey, Craig A.

2000-01-01

During the autumn of 1997, the U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency, began a study to determine the volume of water associated with recent flood events in parts of the Midwestern United States and a preliminary evaluation of the potential upland areas for storage of flood-waters in selected watersheds. This analysis, although preliminary, may be useful in determining the feasibility of conducting additional, more detailed studies into the role of upland areas in a watershed management strategy. The methods and results of this preliminary hydrologic study are presented in this report.

Wing walls for enhancing the seismic performance of reinforced concrete frame structures

NASA Astrophysics Data System (ADS)

Yang, Weisong; Guo, Xun; Xu, Weixiao; Yuan, Xin

2016-06-01

A building retrofitted with wing walls in the bottom story, which was damaged during the 2008 M8.0 Wenchuan earthquake in China, is introduced and a corresponding 1/4 scale wing wall-frame model was subjected to shake table motions to study the seismic behavior of this retrofitted structural system. The results show that wing walls can effectively protect columns from damage by moving areas that bear reciprocating tension and compression to the sections of the wing walls, thus achieving an extra measure of seismic fortification. A `strong column-weak beam' mechanism was realized, the flexural rigidity of the vertical member was strengthened, and a more uniform distribution of deformation among all the stories was measured. In addition, the joint between the wing walls and the beams suffered severe damage during the tests, due to an area of local stress concentration. A longer area of intensive stirrup is suggested in the end of the beams.

PREFACE: Domain wall dynamics in nanostructures Domain wall dynamics in nanostructures

NASA Astrophysics Data System (ADS)

Marrows, C. H.; Meier, G.

2012-01-01

Domain structures in magnetic materials are ubiquitous and have been studied for decades. The walls that separate them are topological defects in the magnetic order parameter and have a wide variety of complex forms. In general, their investigation is difficult in bulk materials since only the domain structure on the surface of a specimen is visible. Cutting the sample to reveal the interior causes a rearrangement of the domains into a new form. As with many other areas of magnetism, the study of domain wall physics has been revitalised by the advent of nanotechnology. The ability to fabricate nanoscale structures has permitted the formation of simplified and controlled domain patterns; the development of advanced microscopy methods has permitted them to be imaged and then modelled; subjecting them to ultrashort field and current pulses has permitted their dynamics to be explored. The latest results from all of these advances are described in this special issue. Not only has this led to results of great scientific beauty, but also to concepts of great applicability to future information technologies. In this issue the reader will find the latest results for these domain wall dynamics and the high-speed processes of topological structures such as domain walls and magnetic vortices. These dynamics can be driven by the application of magnetic fields, or by flowing currents through spintronic devices using the novel physics of spin-transfer torque. This complexity has been studied using a wide variety of experimental techniques at the edge of the spatial and temporal resolution currently available, and can be described using sophisticated analytical theory and computational modelling. As a result, the dynamics can be engineered to give rise to finely controlled memory and logic devices with new functionality. Moreover, the field is moving to study not only the conventional transition metal ferromagnets, but also complex heterostructures, novel magnets and even other

Analysis of wall shear stress around a competitive swimmer using 3D Navier-Stokes equations in CFD.

PubMed

Popa, C V; Zaidi, H; Arfaoui, A; Polidori, G; Taiar, R; Fohanno, S

2011-01-01

This paper deals with the flow dynamics around a competitive swimmer during underwater glide phases occurring at the start and at every turn. The influence of the head position, namely lifted up, aligned and lowered, on the wall shear stress and the static pressure distributions is analyzed. The problem is considered as 3D and in steady hydrodynamic state. Three velocities (1.4 m/s, 2.2 m/s and 3.1 m/s) that correspond to inter-regional, national and international swimming levels are studied. The flow around the swimmer is assumed turbulent. The Reynolds-averaged Navier-Stokes (RANS) equations are solved with the standard k-ω turbulent model by using the CFD (computational fluid dynamics) numerical method based on a volume control approach. Numerical simulations are carried out with the ANSYS FLUENT® CFD code. The results show that the wall shear stress increases with the velocity and consequently the drag force opposing the movement of the swimmer increases as well. Also, high wall shear stresses are observed in the areas where the body shape, globally rigid in form, presents complex surface geometries such as the head, shoulders, buttocks, heel and chest.

Image-guided intensity-modulated radiotherapy for prostate cancer: Dose constraints for the anterior rectal wall to minimize rectal toxicity

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

Peterson, Jennifer L., E-mail: peterson.jennifer2@mayo.edu; Buskirk, Steven J.; Heckman, Michael G.

2014-04-01

Rectal adverse events (AEs) are a major concern with definitive radiotherapy (RT) treatment for prostate cancer. The anterior rectal wall is at the greatest risk of injury as it lies closest to the target volume and receives the highest dose of RT. This study evaluated the absolute volume of anterior rectal wall receiving a high dose to identify potential ideal dose constraints that can minimize rectal AEs. A total of 111 consecutive patients with Stage T1c to T3a N0 M0 prostate cancer who underwent image-guided intensity-modulated RT at our institution were included. AEs were graded according to the Common Terminologymore » Criteria for Adverse Events, version 4.0. The volume of anterior rectal wall receiving 5 to 80 Gy in 2.5-Gy increments was determined. Multivariable Cox regression models were used to identify cut points in these volumes that led to an increased risk of early and late rectal AEs. Early AEs occurred in most patients (88%); however, relatively few of them (13%) were grade ≥2. At 5 years, the cumulative incidence of late rectal AEs was 37%, with only 5% being grade ≥2. For almost all RT doses, we identified a threshold of irradiated absolute volume of anterior rectal wall above which there was at least a trend toward a significantly higher rate of AEs. Most strikingly, patients with more than 1.29, 0.73, or 0.45 cm{sup 3} of anterior rectal wall exposed to radiation doses of 67.5, 70, or 72.5 Gy, respectively, had a significantly increased risk of late AEs (relative risks [RR]: 2.18 to 2.72; p ≤ 0.041) and of grade ≥ 2 early AEs (RR: 6.36 to 6.48; p = 0.004). Our study provides evidence that definitive image-guided intensity-modulated radiotherapy (IG-IMRT) for prostate cancer is well tolerated and also identifies dose thresholds for the absolute volume of anterior rectal wall above which patients are at greater risk of early and late complications.« less

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.

Thin-walled reinforcement lattice structure for hollow CMC buckets

DOEpatents

de Diego, Peter

2017-06-27

A hollow ceramic matrix composite (CMC) turbine bucket with an internal reinforcement lattice structure has improved vibration properties and stiffness. The lattice structure is formed of thin-walled plies made of CMC. The wall structures are arranged and located according to high stress areas within the hollow bucket. After the melt infiltration process, the mandrels melt away, leaving the wall structure to become the internal lattice reinforcement structure of the bucket.

Modeling the sound transmission between rooms coupled through partition walls by using a diffusion model.

PubMed

Billon, Alexis; Foy, Cédric; Picaut, Judicaël; Valeau, Vincent; Sakout, Anas

2008-06-01

In this paper, a modification of the diffusion model for room acoustics is proposed to account for sound transmission between two rooms, a source room and an adjacent room, which are coupled through a partition wall. A system of two diffusion equations, one for each room, together with a set of two boundary conditions, one for the partition wall and one for the other walls of a room, is obtained and numerically solved. The modified diffusion model is validated by numerical comparisons with the statistical theory for several coupled-room configurations by varying the coupling area surface, the absorption coefficient of each room, and the volume of the adjacent room. An experimental comparison is also carried out for two coupled classrooms. The modified diffusion model results agree very well with both the statistical theory and the experimental data. The diffusion model can then be used as an alternative to the statistical theory, especially when the statistical theory is not applicable, that is, when the reverberant sound field is not diffuse. Moreover, the diffusion model allows the prediction of the spatial distribution of sound energy within each coupled room, while the statistical theory gives only one sound level for each room.

Differential longitudinal changes in cortical thickness, surface area and volume across the adult life span: regions of accelerating and decelerating change.

PubMed

Storsve, Andreas B; Fjell, Anders M; Tamnes, Christian K; Westlye, Lars T; Overbye, Knut; Aasland, Hilde W; Walhovd, Kristine B

2014-06-18

Human cortical thickness and surface area are genetically independent, emerge through different neurobiological events during development, and are sensitive to different clinical conditions. However, the relationship between changes in the two over time is unknown. Additionally, longitudinal studies have almost invariably been restricted to older adults, precluding the delineation of adult life span trajectories of change in cortical structure. In this longitudinal study, we investigated changes in cortical thickness, surface area, and volume after an average interval of 3.6 years in 207 well screened healthy adults aged 23-87 years. We hypothesized that the relationships among metrics are dynamic across the life span, that the primary contributor to cortical volume reductions in aging is cortical thinning, and that magnitude of change varies with age and region. Changes over time were seen in cortical area (mean annual percentage change [APC], -0.19), thickness (APC, -0.35), and volume (APC, -0.51) in most regions. Volume changes were primarily explained by changes in thickness rather than area. A negative relationship between change in thickness and surface area was found across several regions, where more thinning was associated with less decrease in area, and vice versa. Accelerating changes with increasing age was seen in temporal and occipital cortices. In contrast, decelerating changes were seen in prefrontal and anterior cingulate cortices. In conclusion, a dynamic relationship between cortical thickness and surface area changes exists throughout the adult life span. The mixture of accelerating and decelerating changes further demonstrates the importance of studying these metrics across the entire adult life span. Copyright © 2014 the authors 0270-6474/14/348488-11$15.00/0.

Massive multicystic dilatation of the uterine wall with myometrial venous thrombosis during pregnancy.

PubMed

Uotila, J; Dastidar, P; Martikainen, P; Kirkinen, P

2004-09-01

We present a pregnancy complicated by multicystic dilatation of the uterine wall during the second trimester, leading to massive uterine distension, anemia and preterm Cesarean section. The cystic changes detected by ultrasound and magnetic resonance imaging involved the whole uterine wall surrounding the entire amniotic cavity. Histopathological examination revealed the benign nature of the cystic changes, which represented dilated and thrombosed venous lacunae. Disturbed venous drainage, combined with local thrombosis, was likely to have led to the collection of a large volume of blood in the uterine wall and the subsequent multicystic change of the myometrium. Copyright 2004 ISUOG

Complex oxide ferroelectrics: Electrostatic doping by domain walls

DOE PAGES

Maksymovych, Petro

2015-06-19

Electrically conducting interfaces can form, rather unexpectedly, by breaking the translational symmetry of electrically insulating complex oxides. For example, a nanometre-thick heteroepitaxial interface between electronically insulating LaAlO 3 and SrTiO 3 supports a 2D electron gas1 with high mobility of >1,000 cm 2 V -1 s -1 (ref. 2). Such interfaces can exhibit magnetism, superconductivity and phase transitions that may form the functional basis of future electronic devices2. A peculiar conducting interface can be created within a polar ferroelectric oxide by breaking the translational symmetry of the ferroelectric order parameter and creating a so-called ferroelectric domain wall (Fig. 1a,b). Ifmore » the direction of atomic displacements changes at the wall in such a way as to create a discontinuity in the polarization component normal to the wall (Fig. 1a), the domain wall becomes electrostatically charged. It may then attract compensating mobile charges of opposite sign produced by dopant ionization, photoexcitation or other effects, thereby locally, electrostatically doping the host ferroelectric film. In contrast to conductive interfaces between epitaxially grown oxides, domain walls can be reversibly created, positioned and shaped by electric fields, enabling reconfigurable circuitry within the same volume of the material. Now, writing in Nature Nanotechnology, Arnaud Crassous and colleagues at EPFL and University of Geneva demonstrate control and stability of charged conducting domain walls in ferroelectric thin films of BiFeO 3 down to the nanoscale.« less

Water Walls for Life Support

NASA Technical Reports Server (NTRS)

Hammoudeh, Mona (Inventor); Flynn, Michael T. (Inventor); Gormly, Sherwin J. (Inventor); Richardson, Tra-My Justine (Inventor)

2017-01-01

A method and associated system for processing waste gases, liquids and solids, produced by human activity, to separate (i) liquids suitable for processing to produce potable water, (ii) solids and liquids suitable for construction of walls suitable for enclosing a habitat volume and for radiation shielding, and (iii) other fluids and solids that are not suitable for processing. A forward osmosis process and a reverse osmosis process are sequentially combined to reduce fouling and to permit accumulation of different processable substances. The invention may be used for long term life support of human activity.

Coordination Between Ribs Motion and Thoracoabdominal Volumes in Swimmers During Respiratory Maneuvers

PubMed Central

Sarro, Karine J.; Silvatti, Amanda P.; Barros, Ricardo M. L.

2008-01-01

This work aimed to verify if swimmers present better chest wall coordination during breathing than healthy non-athletes analyzing the correlation between ribs motion and the variation of thoracoabdominal volumes. The results of two up-to-date methods based on videogrammetry were correlated in this study. The first one measured the volumes of 4 separate compartments of the chest wall (superior thorax, inferior thorax, superior abdomen and inferior abdomen) as a function of time. The second calculated the rotation angle of the 2nd to the 10th ribs around the quasi-transversal axis also in function of time. The chest wall was represented by 53 markers, attached to the ribs, vertebrae, thorax and abdomen of 15 male swimmers and of 15 non- athletes. A kinematical analysis system equipped with 6 digital video cameras (60Hz) was used to obtain the 3D coordinates of the markers. Correlating the curves of ribs rotation angles with the curves of the separate volumes, swimmers presented higher values than non-athletes when the superior and inferior abdomen were considered and the highest correlation values were found in swimmers for the inferior thorax. These results suggest a better coordination between ribs motion and thoracoabdominal volumes in swimmers, indicating the prevalent and coordinated action of the diaphragm and abdominal muscles to inflate and deflate the chest wall. The results further suggest that swimming practice leads to the formation of an optimized breathing pattern and can partially explain the higher lung volumes found in these athletes reported in literature. Key pointsThe study revealed that swimmers present higher correlation between the ribs motion and the variation of abdominal volumes than non-swimmers, suggesting that swimming practice might lead to the formation of an optimized breathing pattern, increasing the coordination between the thoracoabdominal volumes and the ribs motion.No previous work was found in the literature reporting this

Links between Success in Non-Measurement and Calculation Tasks in Area and Volume Measurement and Pupils' Problems

ERIC Educational Resources Information Center

Tumová, Veronika; Vondrová, Nada

2017-01-01

Measurement in geometry is one of the key areas of school mathematics, however, pupils make serious mistakes when solving problems involving measurement and hold misconceptions. This article focuses on the possible links between lower secondary pupils' (n = 870) success in solving non-measurement tasks and calculations tasks on area and volume and…

Aerial ultrasound source with a circular vibrating plate attached to a rigid circumferential wall

NASA Astrophysics Data System (ADS)

Kuratomi, Ryo; Asami, Takuya; Miura, Hikaru

2018-07-01

We fabricate a transverse vibrating plate attached to a rigid wall integrated at the circumference of a circular vibrating plate that allows a strong sound wave field to be formed in the area encoded by the vibrating plate and rigid wall by installing a wall such as a reflective plate on the rigid wall. The design method for the circular vibrating plate attached to a rigid circumferential wall is investigated. A method of forming a strong standing wave field in an enclosed area constructed with a vibrating plate, cylindrical reflective plate, and parallel reflective plate is developed.

Effects of thermal stress and exercise on blood volume in humans

NASA Technical Reports Server (NTRS)

Harrison, M. H.

1985-01-01

The available experimental data base on the effects of exercise, posture and the environment (heat) on the blood volume, composition and concentration in humans is surveyed in depth to synthesize supportable conclusions. A large disparity is noted in the effective controls which were initiated in previous experimental conditions, resulting in contradictory findings regarding, e.g., hemoconcentrations and hemodilution in response to exercise. Comparisons between the results of exercise and of supine, seated and upright subjects has underscored the importance of gravity in hemoconcentration, particularly in the legs, and the generation of aldotestosterone. Hemoconcentration has been confirmed to increase with exercise in a seated or supine position. Exercise in a heated environment transfers cardiac output from core areas and reduces filtration efficiencies. Also, plasma volume increases, an action which cannot yet be associated with crystalloidal or colloidal influences on the osmotic behavior of cell walls.

An integrated study for mapping the moisture distribution in an ancient damaged wall painting.

PubMed

Capitani, Donatella; Proietti, Noemi; Gobbino, Marco; Soroldoni, Luigi; Casellato, Umberto; Valentini, Massimo; Rosina, Elisabetta

2009-12-01

An integrated study of microclimate monitoring, IR thermography (IRT), gravimetric tests and portable unilateral nuclear magnetic resonance (NMR) was applied in the framework of planning emergency intervention on a very deteriorated wall painting in San Rocco church, Cornaredo (Milan, Italy). The IRT investigation supported by gravimetric tests showed that the worst damage, due to water infiltration, was localized on the wall painting of the northern wall. Unilateral NMR, a new non-destructive technique which measures the hydrogen signal of the moisture and that was applied directly to the wall, allowed a detailed map of the distribution of the moisture in the plaster underlying the wall panting to be obtained. With a proper calibration of the integral of the recorded signal with suitable specimens, each area of the map corresponded to an accurate amount of moisture. IRT, gravimetric tests and unilateral NMR applied to investigate the northern wall painting showed the presence of two wet areas separated by a dry area. The moisture found in the lower area was ascribed to the occurrence of rising damp at the bottom of the wall due to the slope of the garden soil towards the northern exterior. The moisture found in the upper area was ascribed to condensation phenomena associated with the presence of a considerable amount of soluble, hygroscopic salts. In the framework of this integrated study, IRT investigation and gravimetric methods validated portable unilateral NMR as a new analytical tool for measuring in situ and without any sampling of the distribution and amount of moisture in wall paintings.

Improvement in transmission loss of aircraft double wall with resonators

NASA Astrophysics Data System (ADS)

Sun, Jincai; Shi, Liming; Ye, Xining

1991-08-01

A little volume low frequency resonator applicable to double-wall configuration of propeller-driven aircraft was designed on the basis of the principle of Helmholtz resonator. The normal incidence absorption coefficient of the various single resonator has been measured. The agreement between theoretical and experimental results is encouraging. An array of resonators whose resonant frequency at 85 Hz and 160 Hz, respectively, are installed between aircraft double-panel, and it has been shown that transmission loss of the double wall structure with resonators improve 4 dB and 6.5 dB in 1/3rd octave bandwidth at 80 Hz and 160 Hz center frequency, respectively, and 5 dB and 7 dB at resonant frequencies, compared with that of the double wall configuration without resonators.

Computer-aided detection of bladder wall thickening in CT urography (CTU)

NASA Astrophysics Data System (ADS)

Cha, Kenny H.; Hadjiiski, Lubomir M.; Chan, Heang-Ping; Caoili, Elaine M.; Cohan, Richard H.; Weizer, Alon Z.; Gordon, Marshall N.; Samala, Ravi K.

2018-02-01

We are developing a computer-aided detection system for bladder cancer in CT urography (CTU). Bladder wall thickening is a manifestation of bladder cancer and its detection is more challenging than the detection of bladder masses. We first segmented the inner and outer bladder walls using our method that combined deep-learning convolutional neural network with level sets. The non-contrast-enhanced region was separated from the contrast-enhanced region with a maximum-intensity-projection-based method. The non-contrast region was smoothed and gray level threshold was applied to the contrast and non-contrast regions separately to extract the bladder wall and potential lesions. The bladder wall was transformed into a straightened thickness profile, which was analyzed to identify regions of wall thickening candidates. Volume-based features of the wall thickening candidates were analyzed with linear discriminant analysis (LDA) to differentiate bladder wall thickenings from false positives. A data set of 112 patients, 87 with wall thickening and 25 with normal bladders, was collected retrospectively with IRB approval, and split into independent training and test sets. Of the 57 training cases, 44 had bladder wall thickening and 13 were normal. Of the 55 test cases, 43 had wall thickening and 12 were normal. The LDA classifier was trained with the training set and evaluated with the test set. FROC analysis showed that the system achieved sensitivities of 93.2% and 88.4% for the training and test sets, respectively, at 0.5 FPs/case.

Analysis of Heliport Environmental Data: Indianapolis Downtown Heliport Wall Street Heliport. Volume 2. Wall Street Heliport Data Plots

DTIC Science & Technology

1989-05-01

r--S is. WATER FLIGHT CODE A T ION DATA FROCE.SFD 51 !4E FAA ’FCtINICAL CF.N!FR AfLAV’IC CITY AP0 N1 08403 D SPEED F WIND SPEED IS 10 𔃻iP1. OR...08,35 DEEC INDICATE WIND SPEED IN S NG OCCURS IF WIND SPEED IS 10 IlPt. OR GREATER IND S. ING INDICATES WIND SPEED A YORK WALL ST. DR HELIPORT CALM IiI G

Great Wall of China

NASA Image and Video Library

2001-07-21

This ASTER sub-image covers a 12 x 12 km area in northern Shanxi Province, China, and was acquired January 9, 2001. The low sun angle, and light snow cover highlight a section of the Great Wall, visible as a black line running diagonally through the image from lower left to upper right. The Great Wall is over 2000 years old and was built over a period of 1000 years. Stretching 4500 miles from Korea to the Gobi Desert it was first built to protect China from marauders from the north. This image is located at 40.2 degrees north latitude and 112.8 degrees east longitude. http://photojournal.jpl.nasa.gov/catalog/PIA02669

Protective interior wall and attaching means for a fusion reactor vacuum vessel

DOEpatents

Phelps, R.D.; Upham, G.A.; Anderson, P.M.

1985-03-01

The wall basically consists of an array of small rectangular plates attached to the existing walls with threaded fasteners. The protective wall effectively conceals and protects all mounting hardware beneath the plate array, while providing a substantial surface area that will absorb plasma energy.

The agreement between 3D, standard 2D and triplane 2D speckle tracking: effects of image quality and 3D volume rate.

PubMed

Trache, Tudor; Stöbe, Stephan; Tarr, Adrienn; Pfeiffer, Dietrich; Hagendorff, Andreas

2014-12-01

Comparison of 3D and 2D speckle tracking performed on standard 2D and triplane 2D datasets of normal and pathological left ventricular (LV) wall-motion patterns with a focus on the effect that 3D volume rate (3DVR), image quality and tracking artifacts have on the agreement between 2D and 3D speckle tracking. 37 patients with normal LV function and 18 patients with ischaemic wall-motion abnormalities underwent 2D and 3D echocardiography, followed by offline speckle tracking measurements. The values of 3D global, regional and segmental strain were compared with the standard 2D and triplane 2D strain values. Correlation analysis with the LV ejection fraction (LVEF) was also performed. The 3D and 2D global strain values correlated good in both normally and abnormally contracting hearts, though systematic differences between the two methods were observed. Of the 3D strain parameters, the area strain showed the best correlation with the LVEF. The numerical agreement of 3D and 2D analyses varied significantly with the volume rate and image quality of the 3D datasets. The highest correlation between 2D and 3D peak systolic strain values was found between 3D area and standard 2D longitudinal strain. Regional wall-motion abnormalities were similarly detected by 2D and 3D speckle tracking. 2DST of triplane datasets showed similar results to those of conventional 2D datasets. 2D and 3D speckle tracking similarly detect normal and pathological wall-motion patterns. Limited image quality has a significant impact on the agreement between 3D and 2D numerical strain values.

MCNP modelling of the wall effects observed in tissue-equivalent proportional counters.

PubMed

Hoff, J L; Townsend, L W

2002-01-01

Tissue-equivalent proportional counters (TEPCs) utilise tissue-equivalent materials to depict homogeneous microscopic volumes of human tissue. Although both the walls and gas simulate the same medium, they respond to radiation differently. Density differences between the two materials cause distortions, or wall effects, in measurements, with the most dominant effect caused by delta rays. This study uses a Monte Carlo transport code, MCNP, to simulate the transport of secondary electrons within a TEPC. The Rudd model, a singly differential cross section with no dependence on electron direction, is used to describe the energy spectrum obtained by the impact of two iron beams on water. Based on the models used in this study, a wall-less TEPC had a higher lineal energy (keV.micron-1) as a function of impact parameter than a solid-wall TEPC for the iron beams under consideration. An important conclusion of this study is that MCNP has the ability to model the wall effects observed in TEPCs.

Probability and volume of potential postwildfire debris flows in the 2012 High Park Burn Area near Fort Collins, Colorado

USGS Publications Warehouse

Verdin, Kristine L.; Dupree, Jean A.; Elliott, John G.

2012-01-01

This report presents a preliminary emergency assessment of the debris-flow hazards from drainage basins burned by the 2012 High Park fire near Fort Collins in Larimer County, Colorado. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of debris-flow occurrence and volume of debris flows along the burned area drainage network and to estimate the same for 44 selected drainage basins along State Highway 14 and the perimeter of the burned area. Input data for the models included topographic parameters, soil characteristics, burn severity, and rainfall totals and intensities for a (1) 2-year-recurrence, 1-hour-duration rainfall (25 millimeters); (2) 10-year-recurrence, 1-hour-duration rainfall (43 millimeters); and (3) 25-year-recurrence, 1-hour-duration rainfall (51 millimeters). Estimated debris-flow probabilities along the drainage network and throughout the drainage basins of interest ranged from 1 to 84 percent in response to the 2-year-recurrence, 1-hour-duration rainfall; from 2 to 95 percent in response to the 10-year-recurrence, 1-hour-duration rainfall; and from 3 to 97 in response to the 25-year-recurrence, 1-hour-duration rainfall. Basins and drainage networks with the highest probabilities tended to be those on the eastern edge of the burn area where soils have relatively high clay contents and gradients are steep. Estimated debris-flow volumes range from a low of 1,600 cubic meters to a high of greater than 100,000 cubic meters. Estimated debris-flow volumes increase with basin size and distance along the drainage network, but some smaller drainages were also predicted to produce substantial volumes of material. The predicted probabilities and some of the volumes predicted for the modeled storms indicate a potential for substantial debris-flow impacts on structures, roads, bridges, and culverts located both within and

Modelling the standing timber volume of Baden-Württemberg-A large-scale approach using a fusion of Landsat, airborne LiDAR and National Forest Inventory data

NASA Astrophysics Data System (ADS)

Maack, Joachim; Lingenfelder, Marcus; Weinacker, Holger; Koch, Barbara

2016-07-01

Remote sensing-based timber volume estimation is key for modelling the regional potential, accessibility and price of lignocellulosic raw material for an emerging bioeconomy. We used a unique wall-to-wall airborne LiDAR dataset and Landsat 7 satellite images in combination with terrestrial inventory data derived from the National Forest Inventory (NFI), and applied generalized additive models (GAM) to estimate spatially explicit timber distribution and volume in forested areas. Since the NFI data showed an underlying structure regarding size and ownership, we additionally constructed a socio-economic predictor to enhance the accuracy of the analysis. Furthermore, we balanced the training dataset with a bootstrap method to achieve unbiased regression weights for interpolating timber volume. Finally, we compared and discussed the model performance of the original approach (r2 = 0.56, NRMSE = 9.65%), the approach with balanced training data (r2 = 0.69, NRMSE = 12.43%) and the final approach with balanced training data and the additional socio-economic predictor (r2 = 0.72, NRMSE = 12.17%). The results demonstrate the usefulness of remote sensing techniques for mapping timber volume for a future lignocellulose-based bioeconomy.

Viscoelastic behavior of lung and chest wall in dogs determined by flow interruption.

PubMed

Similowski, T; Levy, P; Corbeil, C; Albala, M; Pariente, R; Derenne, J P; Bates, J H; Jonson, B; Milic-Emili, J

1989-12-01

Pulmonary and chest wall mechanics were studied in six anesthetized paralyzed dogs, by use of the technique of rapid airway occlusion during constant flow inflation. Analysis of the pressure changes after flow interruption allowed us to partition the overall resistance of the lung (Rl) and chest wall (Rw) and total respiratory system (Rrs) into two components, one (Rinit) reflecting in the lung airway resistance (Raw), the other (delta R) reflecting primarily the viscoelastic properties of the pulmonary and chest wall tissues. The effects of varying inspiratory flow and inflation volume were interpreted in terms of frequency dependence of resistance, by using a spring-and-dashpot model previously proposed and substantiated by Bates et al. (Proc. 9th Annu. Conf. IEEE Med. Biol. Soc., 1987, vol. 3, p. 1802-1803). We observed that 1) Raw and Rw,init were nearly equal and small relative to Rl and Rw (both were unaffected by flow); 2) Rrs,init decreased slightly with increasing volume; 3) both delta Rl and delta Rw decreased with increasing flow and increased with increasing lung volume. These changes were manifestations of frequency dependence of delta R, as it is predicted by the model; 4) Rrs, Rl, and Rw followed the same trends as delta R. These results corroborate data previously reported in the literature with the use of different techniques to measure airways and pulmonary tissue resistances and confirm that the use of Rl to assess bronchial reactivity is problematic. The interrupter techniques provides a convenient way to obtain Raw values, as well as analogs of lung and chest wall tissue resistances in intact dogs.

Wall Y+ approach for dealing with turbulent flow through a constant area duct

NASA Astrophysics Data System (ADS)

Shukla, Isha; Tupkari, Swapnil S.; Raman, Ashok K.; Mullick, A. N.

2012-06-01

The study of flow development in curved ducts has been carried out since the last century. It is of fundamental interest because of its numerous applications in fluid engineering, such as flow through pipeline, in heat exchangers, ventilators, gas turbines, aircraft intakes, gas turbines and centrifugal pumps. The flow development through this type of curved ducts depends on its geometrical and dynamical parameters. In the present paper an approach has been made for dealing with turbulent flows within a curved duct with a rectangular cross-section and the result obtained from the experimental work has been compared and validated through numerical simulation by using Fluent CFD codes. The experiment is carried out at mass average velocity based on the inlet cross section as 40m/s. In the present study using the wall y+ as guidance in selecting the appropriate grid configuration and corresponding turbulence models are investigated. The standard k-ɛ, standard k-ω, Reynolds Stress Model (RSM) and Spalart-Almaras (SA) turbulence models are used to solve the closure problem. Their behaviours together with the accompanying near-wall treatments are investigated for wall Y+ value less than 5 covering the viscous sub layer and Y+ value ranging 5 to 30 in the buffer region. Notably, adopting a wall Y+ in the log-law region, where Y+ value is greater than 30, has also been taken care during the study. After various trials the optimum results were obtained for the K-ω model with a mesh count of 0.54 millions. In this, the value of Y+ was almost within the required range, i.e. 5wall y+ approach and it has been observed that the K-ω model is also best turbulent model among the four turbulent models mentioned earlier, for predicting the flow through this type of geometry. In the second part of the study an attempt has been made to find out the best model by comparing the computational and experimental results. The mean

Inhomogeneity of Cellulose Microfibril Assembly in Plant Cell Walls Revealed with Sum Frequency Generation Microscopy.

PubMed

Huang, Shixin; Makarem, Mohamadamin; Kiemle, Sarah N; Hamedi, Hossein; Sau, Moujhuri; Cosgrove, Daniel J; Kim, Seong H

2018-05-17

Sum frequency generation (SFG) vibrational spectroscopy can selectively detect and analyze noncentrosymmetric components interspersed in amorphous matrices; this principle has been used for studies of nanoscale structure and mesoscale assembly of cellulose in plant cell walls. However, the spectral information averaged over a large area or volume cannot provide regiospecific or tissue-specific information of different cells in plants. This study demonstrates spatially resolved SFG analysis and imaging by combining a broad-band SFG spectroscopy system with an optical microscope. The system was designed to irradiate both narrow-band 800 nm and broad-band tunable IR beams through a single reflective objective lens, but from opposite sides of the surface normal direction of the sample. The developed technique was used to reveal inhomogeneous distributions of cellulose microfibrils within single cell walls, such as cotton fibers and onion epidermis as well as among different tissues in Arabidopsis inflorescence stems and bamboo culms. SFG microscopy can be used for vibrational spectroscopic imaging of other biological systems in complement to conventional Fourier transform infrared spectroscopy and confocal Raman microscopy.

Respiratory muscles stretching acutely increases expansion in hemiparetic chest wall.

PubMed

Rattes, Catarina; Campos, Shirley Lima; Morais, Caio; Gonçalves, Thiago; Sayão, Larissa Bouwman; Galindo-Filho, Valdecir Castor; Parreira, Verônica; Aliverti, Andrea; Dornelas de Andrade, Armèle

2018-08-01

Individuals post-stroke may present restrictive ventilatory pattern generated from changes in the functionality of respiratory system due to muscle spasticity and contractures. Objective was to assess the acute effects after respiratory muscle stretching on the ventilatory pattern and volume distribution of the chest wall in stroke subjects. Ten volunteers with right hemiparesis after stroke and a mean age of 60 ± 5.7 years were randomised into the following interventions: respiratory muscle stretching and at rest (control). The ventilatory pattern and chest wall volume distribution were evaluated through optoelectronic plethysmography before and immediately after each intervention. Respiratory muscle stretching promoted a significant acute increase of 120 mL in tidal volume, with an increase in minute ventilation, mean inspiratory flow and mean expiratory flow compared with the control group. Pulmonary ribcage increased 50 mL after stretching, with 30 mL of contribution to the right pulmonary rib cage (hemiparetic side) in comparison to the control group. Respiratory muscle stretching in patients with right hemiparesis post-stroke demonstrated that acute effects improve the expansion of the respiratory system during tidal breathing. NCT02416349 (URL: https://clinicaltrials.gov/ct2/show/ NCT02416349). Copyright © 2018 Elsevier B.V. All rights reserved.

High rate capacitive performance of single-walled carbon nanotube aerogels

DOE PAGES

Van Aken, Katherine L.; Pérez, Carlos R.; Oh, Youngseok; ...

2015-05-30

Single-walled carbon nanotube (SWCNT) aerogels produced by critical-point-drying of wet-gel precursors exhibit unique properties, such as high surface-area-to-volume and strength-to-weight ratios. They are free-standing, are binder-free, and can be scaled to thicknesses of more than 1 mm. In this paper, we examine the electric double layer capacitive behavior of these materials using a common room temperature ionic liquid electrolyte, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TFSI). Electrochemical performance is assessed through galvanostatic cycling, cyclic voltammetry and impedance spectroscopy. Results indicate stable capacitive performance over 10,000 cycles as well as an impressive performance at high charge and discharge rates, due to accessible pore networks andmore » enhanced electronic and ionic conductivities of SWCNT aerogels. Finally, these materials can find applications in mechanically compressible and flexible supercapacitor devices with high power requirements.« less

Wall characterization for through-the-wall radar applications

NASA Astrophysics Data System (ADS)

Greneker, Gene; Rausch, E. O.

2008-04-01

There has been continuing interest in the penetration of multilayer building materials, such as wood walls with air gaps and concrete hollow core block, using through-the-wall (TTW) radar systems. TTW operational techniques and signal propagation paths vary depending on how the TTW system is intended to be operated. For example, the operator of a TTW radar may be required to place the radar against the intervening wall of interest while collecting data. Other operational doctrines allow the radar to be operated in a stand-off mode from the wall. The stand-off distances can vary from feet to hundreds of feet, depending on the type of radar being used. When a signal is propagated through a multilayer wall with air gaps between the material and the wall construction uses materials of radically different dielectric constants, attenuation may not be the only effect that the probing signal experiences passing through the wall. This paper presents measurements of a hollow core concrete block wall and the measurement of a standard wall constructed of siding and wallboard. Both types of walls are typically found in most U.S. homes. These limited measurements demonstrate that the type of wall being penetrated by a wideband signal can modify the probing signal.

A Near-Wall Reynolds-Stress Closure without Wall Normals

NASA Technical Reports Server (NTRS)

Yuan, S. P.; So, R. M. C.

1997-01-01

With the aid of near-wall asymptotic analysis and results of direct numerical simulation, a new near-wall Reynolds stress model (NNWRS) is formulated based on the SSG high-Reynolds-stress model with wall-independent near-wall corrections. Only one damping function is used for flows with a wide range of Reynolds numbers to ensure that the near-wall modifications diminish away from the walls. The model is able to reproduce complicated flow phenomena induced by complex geometry, such as flow recirculation, reattachment and boundary-layer redevelopment in backward-facing step flow and secondary flow in three-dimensional square duct flow. In simple flows, including fully developed channel/pipe flow, Couette flow and boundary-layer flow, the wall effects are dominant, and the NNWRS model predicts less degree of turbulent anisotropy in the near-wall region compared with a wall-dependent near-wall Reynolds Stress model (NWRS) developed by So and colleagues. The comparison of the predictions given by the two models rectifies the misconception that the overshooting of skin friction coefficient in backward-facing step flow prevalent in those near-wall, models with wall normal is caused by he use of wall normal.

Iterative Otsu's method for OCT improved delineation in the aorta wall

NASA Astrophysics Data System (ADS)

Alonso, Daniel; Real, Eusebio; Val-Bernal, José F.; Revuelta, José M.; Pontón, Alejandro; Calvo Díez, Marta; Mayorga, Marta; López-Higuera, José M.; Conde, Olga M.

2015-07-01

Degradation of human ascending thoracic aorta has been visualized with Optical Coherence Tomography (OCT). OCT images of the vessel wall exhibit structural degradation in the media layer of the artery, being this disorder the final trigger of the pathology. The degeneration in the vessel wall appears as low-reflectivity areas due to different optical properties of acidic polysaccharides and mucopolysaccharides in contrast with typical ordered structure of smooth muscle cells, elastin and collagen fibers. An OCT dimension indicator of wall degradation can be generated upon the spatial quantification of the extension of degraded areas in a similar way as conventional histopathology. This proposed OCT marker can offer in the future a real-time clinical perception of the vessel status to help cardiovascular surgeons in vessel repair interventions. However, the delineation of degraded areas on the B-scan image from OCT is sometimes difficult due to presence of speckle noise, variable signal to noise ratio (SNR) conditions on the measurement process, etc. Degraded areas can be delimited by basic thresholding techniques taking advantage of disorders evidences in B-scan images, but this delineation is not optimum in the aorta samples and requires complex additional processing stages. This work proposes an optimized delineation of degraded areas within the aorta wall, robust to noisy environments, based on the iterative application of Otsu's thresholding method. Results improve the delineation of wall anomalies compared with the simple application of the algorithm. Achievements could be also transferred to other clinical scenarios: carotid arteries, aorto-iliac or ilio-femoral sections, intracranial, etc.

Controlled dexamethasone delivery via double-walled microspheres to enhance long-term adipose tissue retention

PubMed Central

Kelmendi-Doko, Arta; Rubin, J Peter; Klett, Katarina; Mahoney, Christopher; Wang, Sheri; Marra, Kacey G

2017-01-01

Current materials used for adipose tissue reconstruction have critical shortcomings such as suboptimal volume retention, donor-site morbidity, and poor biocompatibility. The aim of this study was to examine a controlled delivery system of dexamethasone to generate stable adipose tissue when mixed with disaggregated human fat in an athymic mouse model for 6 months. The hypothesis that the continued release of dexamethasone from polymeric microspheres would enhance both adipogenesis and angiogenesis more significantly when compared to the single-walled microsphere model, resulting in long-term adipose volume retention, was tested. Dexamethasone was encapsulated within single-walled poly(lactic-co-glycolic acid) microspheres (Dex SW MS) and compared to dexamethasone encapsulated in a poly(lactic-co-glycolic acid) core surrounded by a shell of poly-l-lactide. The double-walled polymer microsphere system in the second model was developed to create a more sustainable drug delivery process. Dexamethasone-loaded poly(lactic-co-glycolic acid) microspheres (Dex SW MS) and dexamethasone-loaded poly(lactic-co-glycolic acid)/poly-l-lactide double-walled microspheres (Dex DW MS) were prepared using single and double emulsion/solvent techniques. In vitro release kinetics were determined. Two doses of each type of microsphere were examined; 50 and 27 mg of Dex MS and Dex DW MS were mixed with 0.3 mL of human lipoaspirate. Additionally, 50 mg of empty MS and lipoaspirate-only controls were examined. Samples were analyzed grossly and histologically after 6 months in vivo. Mass and volume were measured; dexamethasone microsphere-containing samples demonstrated greater adipose tissue retention compared to the control group. Histological analysis, including hematoxylin and eosin and CD31 staining, indicated increased vascularization (p < 0.05) within the Dex MS-containing samples. Controlled delivery of adipogenic factors, such as dexamethasone via polymer microspheres, significantly

The terminal area simulation system. Volume 2: Verification cases

NASA Technical Reports Server (NTRS)

Proctor, F. H.

1987-01-01

The numerical simulation of five case studies are presented and are compared with available data in order to verify the three-dimensional version of the Terminal Area Simulation System (TASS). A spectrum of convective storm types are selected for the case studies. Included are: a High-Plains supercell hailstorm, a small and relatively short-lived High-Plains cumulonimbus, a convective storm which produced the 2 August 1985 DFW microburst, a South Florida convective complex, and a tornadic Oklahoma thunderstorm. For each of the cases the model results compared reasonably well with observed data. In the simulations of the supercell storms many of their characteristic features were modeled, such as the hook echo, BWER, mesocyclone, gust fronts, giant persistent updraft, wall cloud, flanking-line towers, anvil and radar reflectivity overhang, and rightward veering in the storm propagation. In the simulation of the tornadic storm a horseshoe-shaped updraft configuration and cyclic changes in storm intensity and structure were noted. The simulation of the DFW microburst agreed remarkably well with sparse observed data. The simulated outflow rapidly expanded in a nearly symmetrical pattern and was associated with a ringvortex. A South Florida convective complex was simulated and contained updrafts and downdrafts in the form of discrete bubbles. The numerical simulations, in all cases, always remained stable and bounded with no anomalous trends.

Arterial Wall Perfusion Measured with Photon Counting Spectral X-ray CT.

PubMed

Jorgensen, Steven M; Korinek, Mark J; Vercnocke, Andrew J; Anderson, Jill L; Halaweish, Ahmed; Leng, Shuai; McCollough, Cynthia H; Ritman, Erik L

2016-08-28

Early atherosclerosis changes perfusion of the arterial wall due to localized proliferation of the vasa vasorum. When contrast agent passes through the artery, some enters the vasa vasorum and increases radiopacity of the arterial wall. Technical challenges to detecting changes in vasa vasorum density include the thin arterial wall, partial volume averaging at the arterial lumen/wall interface and calcification within the wall. We used a photon-counting spectral CT scanner to study carotid arteries of anesthetized pigs and micro-CT of these arteries to quantify vasa vasorum density. The left carotid artery wall was injected with autologous blood to stimulate vasa vasorum angiogenesis. The scans were performed at 25-120 keV; the tube-current-time product was 550 mAs. A 60 mL bolus of iodine contrast agent was injected into the femoral vein at 5mL/s. Two seconds post injection, an axial scan was acquired at every 3 s over 60 s (i.e., 20 time points). Each time point acquired 28 contiguous transaxial slices with reconstructed voxels 0.16 × 0.16 × 1 mm 3 . Regions-of-interest in the outer 2/3 of the arterial wall and in the middle 2/3 of the lumen were drawn and their enhancements plotted versus time. Lumenal CT values peaked several seconds after injection and then returned towards baseline. Arterial wall CT values peaked concurrent to the lumen. The peak arterial wall enhancement in the left carotid arterial wall correlated with increased vasa vasorum density observed in micro-CT images of the isolated arteries.

Arterial wall perfusion measured with photon counting spectral x-ray CT

NASA Astrophysics Data System (ADS)

Jorgensen, Steven M.; Korinek, Mark J.; Vercnocke, Andrew J.; Anderson, Jill L.; Halaweish, Ahmed; Leng, Shuai; McCollough, Cynthia H.; Ritman, Erik L.

2016-10-01

Early atherosclerosis changes perfusion of the arterial wall due to localized proliferation of the vasa vasorum. When contrast agent passes through the artery, some enters the vasa vasorum and increases radiopacity of the arterial wall. Technical challenges to detecting changes in vasa vasorum density include the thin arterial wall, partial volume averaging at the arterial lumen/wall interface and calcification within the wall. We used a photon-counting spectral CT scanner to study carotid arteries of anesthetized pigs and micro-CT of these arteries to quantify vasa vasorum density. The left carotid artery wall was injected with autologous blood to stimulate vasa vasorum angiogenesis. The scans were performed at 25-120 keV; the tube-current-time product was 550 mAs. A 60 mL bolus of iodine contrast agent was injected into the femoral vein at 5mL/s. Two seconds post injection, an axial scan was acquired at every 3 s over 60 s (i.e., 20 time points). Each time point acquired 28 contiguous transaxial slices with reconstructed voxels 0.16 x 0.16 x 1 mm3. Regions-of-interest in the outer 2/3 of the arterial wall and in the middle 2/3 of the lumen were drawn and their enhancements plotted versus time. Lumenal CT values peaked several seconds after injection and then returned towards baseline. Arterial wall CT values peaked concurrent to the lumen. The peak arterial wall enhancement in the left carotid arterial wall correlated with increased vasa vasorum density observed in micro-CT images of the isolated arteries.

A Study on Sixth Grade Students' Misconceptions and Errors in Spatial Measurement: Length, Area, and Volume

ERIC Educational Resources Information Center

Tan Sisman, Gulcin; Aksu, Meral

2016-01-01

The purpose of the present study was to portray students' misconceptions and errors while solving conceptually and procedurally oriented tasks involving length, area, and volume measurement. The data were collected from 445 sixth grade students attending public primary schools in Ankara, Türkiye via a test composed of 16 constructed-response…

Electrochemical reduction of nalidixic acid at glassy carbon electrode modified with multi-walled carbon nanotubes.

PubMed

Patiño, Yolanda; Pilehvar, Sanaz; Díaz, Eva; Ordóñez, Salvador; De Wael, Karolien

2017-02-05

The aqueous phase electrochemical degradation of nalidixic acid (NAL) is studied in this work, using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) as instrumental techniques. The promotional effect of multi-walled carbon nanotubes (MWCNT) on the performance of glassy carbon electrodes is demonstrated, being observed that these materials catalyze the NAL reduction. The effect of surface functional groups on MWCNT -MWCNT-COOH and MWCNT-NH 2 -was also studied. The modification of glassy carbon electrode (GCE) with MWCNT leads to an improved performance for NAL reduction following the order of MWCNT>MWCNT-NH 2 >MWCNT-COOH. The best behavior at MWCNT-GCE is mainly due to both the increased electrode active area and the enhanced MWCNT adsorption properties. The NAL degradation was carried out under optimal conditions (pH=5.0, deposition time=20s and volume of MWCNT=10μL) using MWCNT-GCE obtaining an irreversible reduction of NAL to less toxic products. Paramaters as the number of DPV cycles and the volume/area (V/A) ratio were optimized for maximize pollutant degradation. It was observed that after 15 DPV scans and V/A=8, a complete reduction was obtained, obtaining two sub-products identified by liquid chromatography-mass spectrometry (LC-MS). Copyright © 2016 Elsevier B.V. All rights reserved.

Reliability of tanoak volume equations when applied to different areas

Treesearch

Norman H. Pillsbury; Philip M. McDonald; Victor Simon

1995-01-01

Tree volume equations for tanoak (Lithocarpus densiflorus) were developed for seven stands throughout its natural range and compared by a volume prediction and a parameter difference method. The objective was to test if volume estimates from a species growing in a local, relatively uniform habitat could be applied more widely. Results indicated...

8. BUILDING 313, INTERIOR, EAST WALL OF EASTERN STOREROOM, LOOKING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. BUILDING 313, INTERIOR, EAST WALL OF EASTERN STOREROOM, LOOKING NORTHEAST, WITH TIME CLOCK AND FIRE SPRINKLER CONTROLS ON WALL, AND ENTRY TO OFFICE AREA AT LEFT. - Oakland Naval Supply Center, General Storehouses, Between Third & Fourth Streets, North of A Street, Oakland, Alameda County, CA

Adjusting tidal volume to stress index in an open lung condition optimizes ventilation and prevents overdistension in an experimental model of lung injury and reduced chest wall compliance.

PubMed

Ferrando, Carlos; Suárez-Sipmann, Fernando; Gutierrez, Andrea; Tusman, Gerardo; Carbonell, Jose; García, Marisa; Piqueras, Laura; Compañ, Desamparados; Flores, Susanie; Soro, Marina; Llombart, Alicia; Belda, Francisco Javier

2015-01-13

The stress index (SI), a parameter derived from the shape of the pressure-time curve, can identify injurious mechanical ventilation. We tested the hypothesis that adjusting tidal volume (VT) to a non-injurious SI in an open lung condition avoids hypoventilation while preventing overdistension in an experimental model of combined lung injury and low chest-wall compliance (Ccw). Lung injury was induced by repeated lung lavages using warm saline solution, and Ccw was reduced by controlled intra-abdominal air-insufflation in 22 anesthetized, paralyzed and mechanically ventilated pigs. After injury animals were recruited and submitted to a positive end-expiratory pressure (PEEP) titration trial to find the PEEP level resulting in maximum compliance. During a subsequent four hours of mechanical ventilation, VT was adjusted to keep a plateau pressure (Pplat) of 30 cmH2O (Pplat-group, n = 11) or to a SI between 0.95 and 1.05 (SI-group, n = 11). Respiratory rate was adjusted to maintain a 'normal' PaCO2 (35 to 65 mmHg). SI, lung mechanics, arterial-blood gases haemodynamics pro-inflammatory cytokines and histopathology were analyzed. In addition Computed Tomography (CT) data were acquired at end expiration and end inspiration in six animals. PaCO2 was significantly higher in the Pplat-group (82 versus 53 mmHg, P = 0.01), with a resulting lower pH (7.19 versus 7.34, P = 0.01). We observed significant differences in VT (7.3 versus 5.4 mlKg(-1), P = 0.002) and Pplat values (30 versus 35 cmH2O, P = 0.001) between the Pplat-group and SI-group respectively. SI (1.03 versus 0.99, P = 0.42) and end-inspiratory transpulmonary pressure (PTP) (17 versus 18 cmH2O, P = 0.42) were similar in the Pplat- and SI-groups respectively, without differences in overinflated lung areas at end- inspiration in both groups. Cytokines and histopathology showed no differences. Setting tidal volume to a non-injurious stress index in an open lung condition improves

Love Canal Emergency Declaration Area habitability study. Volume 5. Peer review summary: TRC (Technical Review Committee) responses. Final report

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

Not Available

Environmental studies were conducted to provide data that could be used by the Commissioner of Health for the State of New York in determining whether the Emergency Declaration Area surrounding the Love Canal hazardous-waste site is habitable. These volumes (II through IV) were reviewed by a peer-review panel of expert scientists. The scientists concluded that each of the three environmental studies was well planned and well executed. Volume V summarizes the peer review and gives additional information or clarifications as requested during the peer review. Volume V also provides additional supplemental statistical analyses requested by the peer reviewer panel.

Probability and volume of potential postwildfire debris flows in the 2010 Fourmile burn area, Boulder County, Colorado

USGS Publications Warehouse

Ruddy, Barbara C.; Stevens, Michael R.; Verdin, Kristine

2010-01-01

This report presents a preliminary emergency assessment of the debris-flow hazards from drainage basins burned by the Fourmile Creek fire in Boulder County, Colorado, in 2010. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of debris-flow occurrence and volumes of debris flows for selected drainage basins. Data for the models include burn severity, rainfall total and intensity for a 25-year-recurrence, 1-hour-duration rainstorm, and topographic and soil property characteristics. Several of the selected drainage basins in Fourmile Creek and Gold Run were identified as having probabilities of debris-flow occurrence greater than 60 percent, and many more with probabilities greater than 45 percent, in response to the 25-year recurrence, 1-hour rainfall. None of the Fourmile Canyon Creek drainage basins selected had probabilities greater than 45 percent. Throughout the Gold Run area and the Fourmile Creek area upstream from Gold Run, the higher probabilities tend to be in the basins with southerly aspects (southeast, south, and southwest slopes). Many basins along the perimeter of the fire area were identified as having low probability of occurrence of debris flow. Volume of debris flows predicted from drainage basins with probabilities of occurrence greater than 60 percent ranged from 1,200 to 9,400 m3. The predicted moderately high probabilities and some of the larger volumes responses predicted for the modeled storm indicate a potential for substantial debris-flow effects to buildings, roads, bridges, culverts, and reservoirs located both within these drainages and immediately downstream from the burned area. However, even small debris flows that affect structures at the basin outlets could cause considerable damage.

Airborne gamma-ray spectrometer and magnetometer survey, Durango D, Colorado. Final report Volume II B. Detail area

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

Not Available

1983-01-01

This volume comprises eight appendices containing the following information for the Durango D detail area: flight line maps, geology maps, explanation of geologic legend, flight line/geology maps, radiometric contour maps, magnetic contour maps, multi-variant analysis maps, and geochemical factor analysis maps.

Airborne gamma-ray spectrometer and magnetometer survey, Durango B, Colorado. Final report Volume II C. Detail area

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

Not Available

1983-01-01

This volume contains eight appendices: flight line maps, geology maps, explanation of geologic legend, flight line/geology maps, radiometric contour maps, magnetic contour maps, multi-variant analysis maps, and geochemical factor analysis maps. These appendices pertain to the Durango B detail area.

Airborne gamma-ray spectrometer and magnetometer survey, Durango C, Colorado. Final report Volume II B. Detail area

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

Not Available

1983-01-01

This volume comprises eight appendices containing the following information for the Durango C detail area: flight line maps, geology maps, explanation of geologic legend, flight line/geology maps, radiometric contour maps, magnetic contour maps, multi-variant analysis maps, and geochemical factor analysis maps.

Systems Modeling of a Hypothetical SSME Channel-Wall Nozzle

NASA Technical Reports Server (NTRS)

Greene, William D.; Thames, Mignon P.; Polsgrove, Robert H.

2003-01-01

A future upgrade to the Space Shuttle Main Engine (SSME) may be the replacement of the current regenerative cooled tube-wall nozzle with a nozzle using a regeneratively-cooled channel-wall design. The current tube-wall design represents the only major piece of SSME hardware that has not been dramatically updated throughout thc long history of the engine. There are a number of advantages to a channel-wall design including the promise of faster and lower cost fabrication and greater reliability in the field. The technical obstacles in the path of making this happen are many, particularly in the realms of metallurgy and manufacturing techniques. However, one technical area that can and should be addressed in the near term as part of the development of detailed component requirements is a systems type model of the fluid flow and heat transfer processes to which the new design will be exposed. This paper presents the results of an effort to develop a mathematical model of the internal flow for a generic channel-wall nozzle functioning as a direct replacement for the current tube-wall nozzle with a minimum of systems-level changes. Comparisons will be made to mathematical modeling results for the current tube-wall design and the results of various geometrical trade studies will be presented. It is the intent of this work to examine the feasibility of the concept of a direct replacement component with minimum systems-!eve impacts and to highlight potential areas of concern requiring further work in the future.

Development of the ventral body wall in the human embryo

PubMed Central

Mekonen, Hayelom K; Hikspoors, Jill P J M; Mommen, Greet; Köhler, S Eleonore; Lamers, Wouter H

2015-01-01

Migratory failure of somitic cells is the commonest explanation for ventral body wall defects. However, the embryo increases ∼ 25-fold in volume in the period that the ventral body wall forms, so that differential growth may, instead, account for the observed changes in topography. Human embryos between 4 and 10 weeks of development were studied, using amira® reconstruction and cinema 4D® remodeling software for visualization. Initially, vertebrae and ribs had formed medially, and primordia of sternum and hypaxial flank muscle primordium laterally in the body wall at Carnegie Stage (CS)15 (5.5 weeks). The next week, ribs and muscle primordium expanded in ventrolateral direction only. At CS18 (6.5 weeks), separate intercostal and abdominal wall muscles differentiated, and ribs, sterna, and muscles began to expand ventromedially and caudally, with the bilateral sternal bars fusing in the midline after CS20 (7 weeks) and the rectus muscles reaching the umbilicus at CS23 (8 weeks). The near-constant absolute distance between both rectus muscles and approximately fivefold decline of this distance relative to body circumference between 6 and 10 weeks identified dorsoventral growth in the dorsal body wall as determinant of the ‘closure’ of the ventral body wall. Concomitant with the straightening of the embryonic body axis after the 6th week, the abdominal muscles expanded ventrally and caudally to form the infraumbilical body wall. Our data, therefore, show that the ventral body wall is formed by differential dorsoventral growth in the dorsal part of the body. PMID:26467243

Surface area and the seabed area, volume, depth, slope, and topographic variation for the world's seas, oceans, and countries.

PubMed

Costello, Mark John; Cheung, Alan; De Hauwere, Nathalie

2010-12-01

Depth and topography directly and indirectly influence most ocean environmental conditions, including light penetration and photosynthesis, sedimentation, current movements and stratification, and thus temperature and oxygen gradients. These parameters are thus likely to influence species distribution patterns and productivity in the oceans. They may be considered the foundation for any standardized classification of ocean ecosystems and important correlates of metrics of biodiversity (e.g., species richness and composition, fisheries). While statistics on ocean depth and topography are often quoted, how they were derived is rarely cited, and unless calculated using the same spatial resolution the resulting statistics will not be strictly comparable. We provide such statistics using the best available resolution (1-min) global bathymetry, and open source digital maps of the world's seas and oceans and countries' Exclusive Economic Zones, using a standardized methodology. We created a terrain map and calculated sea surface and seabed area, volume, and mean, standard deviation, maximum, and minimum, of both depth and slope. All the source data and our database are freely available online. We found that although the ocean is flat, and up to 71% of the area has a < 1 degree slope. It had over 1 million approximately circular features that may be seamounts or sea-hills as well as prominent mountain ranges or ridges. However, currently available global data significantly underestimate seabed slopes. The 1-min data set used here predicts there are 68,669 seamounts compared to the 30,314 previously predicted using the same method but lower spatial resolution data. The ocean volume exceeds 1.3 billion km(3) (or 1.3 sextillion liters), and sea surface and seabed areas over 354 million km(2). We propose the coefficient of variation of slope as an index of topographic heterogeneity. Future studies may improve on this database, for example by using a more detailed bathymetry

Probability and volume of potential postwildfire debris flows in the 2012 Waldo Canyon Burn Area near Colorado Springs, Colorado

USGS Publications Warehouse

Verdin, Kristine L.; Dupree, Jean A.; Elliott, John G.

2012-01-01

This report presents a preliminary emergency assessment of the debris-flow hazards from drainage basins burned by the 2012 Waldo Canyon fire near Colorado Springs in El Paso County, Colorado. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the intermountain western United States were used to estimate the probability of debris-flow occurrence and potential volume of debris flows along the drainage network of the burned area and to estimate the same for 22 selected drainage basins along U.S. Highway 24 and the perimeter of the burned area. Input data for the models included topographic parameters, soil characteristics, burn severity, and rainfall totals and intensities for a (1) 2-year-recurrence, 1-hour-duration rainfall, referred to as a 2-year storm (29 millimeters); (2) 10-year-recurrence, 1-hour-duration rainfall, referred to as a 10-year storm (42 millimeters); and (3) 25-year-recurrence, 1-hour-duration rainfall, referred to as a 25-year storm (48 millimeters). Estimated debris-flow probabilities at the pour points of the the drainage basins of interest ranged from less than 1 to 54 percent in response to the 2-year storm; from less than 1 to 74 percent in response to the 10-year storm; and from less than 1 to 82 percent in response to the 25-year storm. Basins and drainage networks with the highest probabilities tended to be those on the southern and southeastern edge of the burn area where soils have relatively high clay contents and gradients are steep. Nine of the 22 drainage basins of interest have greater than a 40-percent probability of producing a debris flow in response to the 10-year storm. Estimated debris-flow volumes for all rainfalls modeled range from a low of 1,500 cubic meters to a high of greater than 100,000 cubic meters. Estimated debris-flow volumes increase with basin size and distance along the drainage network, but some smaller drainages were also predicted to produce

Moisture Management for High R-Value Walls

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

Lepage, R.; Schumacher, C.; Lukachko, A.

2013-11-01

The following report explains the moisture-related concerns for High R-value wall assemblies and discusses past Building America research work that informs this study. Hygrothermal simulations were prepared for several common approaches to High R-value wall construction in six cities (Houston, Atlanta, Seattle, St. Louis, Chicago, and International Falls) representing a range of climate zones (2, 3, 4C, 4, 5A, and 7, respectively). The simulations are informed by experience gained from past research in this area and validated by field measurement and forensic experience. The modeling program was developed to assess the moisture durability of the wall assemblies based on threemore » primary sources of moisture: construction moisture, air leakage condensation, and bulk water leakage. The peak annual moisture content of the wood based exterior sheathing was used to comparatively analyze the response to the moisture loads for each of the walls in each given city. Walls which experienced sheathing moisture contents between 20% and 28% were identified as risky, whereas those exceeding 28% were identified as very high risk. All of the wall assemblies perform well under idealized conditions. However, only the walls with exterior insulation, or cavity insulation which provides a hygrothermal function similar to exterior insulation, perform adequately when exposed to moisture loads. Walls with only cavity insulation are particularly susceptible to air leakage condensation. None of the walls performed well when a precipitation based bulk water leak was introduced to the backside of the sheathing, emphasizing the importance of proper flashing details.« less

Magnetic Resonance Venous Volume Measurements in Peripheral Artery Disease (from ELIMIT).

PubMed

Kamran, Hassan; Nambi, Vijay; Negi, Smita; Yang, Eric Y; Chen, Changyi; Virani, Salim S; Kougias, Panos; Lumsden, Alan B; Morrisett, Joel D; Ballantyne, Christie M; Brunner, Gerd

2016-11-01

The relation between the arterial and venous systems in patients with impaired lower extremity blood flow remains poorly described. The objective of this secondary analysis of the Effectiveness of Intensive Lipid Modification Medication in Preventing the Progression on Peripheral Artery Disease Trial was to determine the association between femoral vein (FV) volumes and measurements of peripheral artery disease. FV wall, lumen, and total volumes were quantified with fast spin-echo proton density-weighted magnetic resonance imaging scans in 79 patients with peripheral artery disease over 2 years. Reproducibility was excellent for FV total vessel (intraclass correlation coefficient 0.924, confidence interval 0.910 to 0.935) and lumen volumes (intraclass correlation coefficient 0.893, confidence interval 0.873 to 0.910). Baseline superficial femoral artery volumes were directly associated with FV wall (r = 0.46, p <0.0001), lumen (r = 0.42, p = 0.0001), and total volumes (r = 0.46, p <0.0001). The 2-year change in maximum walking time was inversely associated with the 24-month change in FV total volume (r = -0.45, p = 0.03). In conclusion, FV volumes can be measured reliably with fast spin-echo proton density-weighted magnetic resonance imaging, and baseline superficial femoral artery plaque burden is positively associated with FV volumes, whereas the 2-year change in FV volumes and leg function show an inverse relation. Copyright © 2016 Elsevier Inc. All rights reserved.

Characterization of mechanical properties of lamellar structure of the aortic wall: Effect of aging.

PubMed

Taghizadeh, Hadi; Tafazzoli-Shadpour, Mohammad

2017-01-01

Arterial wall tissues are sensitive to their mechanical surroundings and remodel their structure and mechanical properties when subjected to mechanical stimuli such as increased arterial pressure. Such remodeling is evident in hypertension and aging. Aging is characterized by stiffening of the artery wall which is assigned to disturbed elastin function and increased collagen content. To better understand and provide new insight on microstructural changes induced by aging, the lamellar model of the aortic media was utilized to characterize and compare wall structure and mechanical behavior of the young and old human thoracic aortic samples. Such model regards arterial media as two sets of alternating concentric layers, namely sheets of elastin and interlamellar layers. Histological and biaxial tests were performed and microstructural features and stress-strain curves of media were evaluated in young and old age groups. Then using optimization algorithms and hyperelastic constitutive equations the stress-strain curves of layers were evaluated for both age groups. Results indicated slight elevation in the volume fraction of interlamellar layer among old subjects most probably due to age related collagen deposition. Aging indicated substantial stiffening of interlamellar layers accompanied by noticeable softening of elastic lamellae. The general significant stiffening of old samples were attributed to both increase of volume fraction of interlamellar layers and earlier recruitment of collagen fibers during load bearing due to functional loss of elastin within wall lamellae. Mechanical characterization of lamellar structure of wall media is beneficial in study of arterial remodeling in response to alternated mechanical environment in aging and clinical conditions through coupling of wall microstructure and mechanical behavior. Copyright © 2016 Elsevier Ltd. All rights reserved.

SND2, a NAC transcription factor gene, regulates genes involved in secondary cell wall development in Arabidopsis fibres and increases fibre cell area in Eucalyptus

PubMed Central

2011-01-01

Background NAC domain transcription factors initiate secondary cell wall biosynthesis in Arabidopsis fibres and vessels by activating numerous transcriptional regulators and biosynthetic genes. NAC family member SND2 is an indirect target of a principal regulator of fibre secondary cell wall formation, SND1. A previous study showed that overexpression of SND2 produced a fibre cell-specific increase in secondary cell wall thickness in Arabidopsis stems, and that the protein was able to transactivate the cellulose synthase8 (CesA8) promoter. However, the full repertoire of genes regulated by SND2 is unknown, and the effect of its overexpression on cell wall chemistry remains unexplored. Results We overexpressed SND2 in Arabidopsis and analyzed homozygous lines with regards to stem chemistry, biomass and fibre secondary cell wall thickness. A line showing upregulation of CesA8 was selected for transcriptome-wide gene expression profiling. We found evidence for upregulation of biosynthetic genes associated with cellulose, xylan, mannan and lignin polymerization in this line, in agreement with significant co-expression of these genes with native SND2 transcripts according to public microarray repositories. Only minor alterations in cell wall chemistry were detected. Transcription factor MYB103, in addition to SND1, was upregulated in SND2-overexpressing plants, and we detected upregulation of genes encoding components of a signal transduction machinery recently proposed to initiate secondary cell wall formation. Several homozygous T4 and hemizygous T1 transgenic lines with pronounced SND2 overexpression levels revealed a negative impact on fibre wall deposition, which may be indirectly attributable to excessive overexpression rather than co-suppression. Conversely, overexpression of SND2 in Eucalyptus stems led to increased fibre cross-sectional cell area. Conclusions This study supports a function for SND2 in the regulation of cellulose and hemicellulose biosynthetic

Determination of burning area and port volume in complex burning regions of a solid rocket motor

NASA Technical Reports Server (NTRS)

Kingsbury, J. A.

1977-01-01

An analysis of the geometry of the burning in both star-cylindrical port interface regions and regions of partially inhibited slots is presented. Some characteristics parameters are defined and illustrated. Methods are proposed for calculating burning areas which functionally depend only on the total distance burned. According to this method, several points are defined where abrupt changes in geometry occur, and these are tracked throughout the burn. Equations are developed for computing port perimeter and port area at pre-established longitudinal positions. Some common formulas and some newly developed formulas are then used to compute burning surface area and port volume. Some specific results are presented for the solid rocket motor committed to the space shuttle project.

Comparative analysis of single-walled and multi-walled carbon nanotubes for electrochemical sensing of glucose on gold printed circuit boards.

PubMed

Alhans, Ruby; Singh, Anukriti; Singhal, Chaitali; Narang, Jagriti; Wadhwa, Shikha; Mathur, Ashish

2018-09-01

In the present work, a comparative study was performed between single-walled carbon nanotubes and multi-walled carbon nanotubes coated gold printed circuit board electrodes for glucose detection. Various characterization techniques were demonstrated in order to compare the modified electrodes viz. cyclic voltammetry, electrochemical impedance spectroscopy and chrono-amperometry. Results revealed that single-walled carbon nanotubes outperformed multi-walled carbon nanotubes and proved to be a better sensing interface for glucose detection. The single-walled carbon nanotubes coated gold printed circuit board electrodes showed a wide linear sensing range (1 mM to 100 mM) with detection limit of 0.1 mM with response time of 5 s while multi-walled carbon nanotubes coated printed circuit board gold electrodes showed linear sensing range (1 mM to 100 mM) with detection limit of 0.1 mM with response time of 5 s. This work provided low cost sensors with enhanced sensitivity, fast response time and reliable results for glucose detection which increased the affordability of such tests in remote areas. In addition, the comparative results confirmed that single-walled carbon nanotubes modified electrodes can be exploited for better amplification signal as compared to multi-walled carbon nanotubes. Copyright © 2018. Published by Elsevier B.V.

Airborne gamma-ray spectrometer and magnetometer survey, Durango D, Colorado. Final report Volume II A. Detail area

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

Not Available

1983-01-01

This volume contains geology of the Durango D detail area, radioactive mineral occurrences in Colorado, and geophysical data interpretation. Eight appendices provide: stacked profiles, geologic histograms, geochemical histograms, speed and altitude histograms, geologic statistical tables, geochemical statistical tables, magnetic and ancillary profiles, and test line data.

Chronic Abdominal Wall Pain.

PubMed

Koop, Herbert; Koprdova, Simona; Schürmann, Christine

2016-01-29

Chronic abdominal wall pain is a poorly recognized clinical problem despite being an important element in the differential diagnosis of abdominal pain. This review is based on pertinent articles that were retrieved by a selective search in PubMed and EMBASE employing the terms "abdominal wall pain" and "cutaneous nerve entrapment syndrome," as well as on the authors' clinical experience. In 2% to 3% of patients with chronic abdominal pain, the pain arises from the abdominal wall; in patients with previously diagnosed chronic abdominal pain who have no demonstrable pathological abnormality, this likelihood can rise as high as 30% . There have only been a small number of clinical trials of treatment for this condition. The diagnosis is made on clinical grounds, with the aid of Carnett's test. The characteristic clinical feature is strictly localized pain in the anterior abdominal wall, which is often mischaracterized as a "functional" complaint. In one study, injection of local anesthesia combined with steroids into the painful area was found to relieve pain for 4 weeks in 95% of patients. The injection of lidocaine alone brought about improvement in 83-91% of patients. Long-term pain relief ensued after a single lidocaine injection in 20-30% of patients, after repeated injections in 40-50% , and after combined lidocaine and steroid injections in up to 80% . Pain that persists despite these treatments can be treated with surgery (neurectomy). Chronic abdominal wall pain is easily diagnosed on physical examination and can often be rapidly treated. Any physician treating patients with abdominal pain should be aware of this condition. Further comparative treatment trials will be needed before a validated treatment algorithm can be established.

Cleopatra's Bedroom oblique with picture tube wall along walkway. Structure ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Cleopatra's Bedroom oblique with picture tube wall along walkway. Structure is made solely of amber colored bottles. Roof supported by telephone poles. Areas of bottle wall above window opening collapsed in the 1994 Northridge earthquake. Camera facing northeast. - Grandma Prisbrey's Bottle Village, 4595 Cochran Street, Simi Valley, Ventura County, CA

Four-wall turbine airfoil with thermal strain control for reduced cycle fatigue

DOEpatents

Cambell, Christian X

2013-09-17

A turbine airfoil (20B) with a thermal expansion control mechanism that increases the airfoil camber (60, 61) under operational heating. The airfoil has four-wall geometry, including pressure side outer and inner walls (26, 28B), and suction side outer and inner walls (32, 34B). It has near-wall cooling channels (31F, 31A, 33F, 33A) between the outer and inner walls. A cooling fluid flow pattern (50C, 50W, 50H) in the airfoil causes the pressure side inner wall (28B) to increase in curvature under operational heating. The pressure side inner wall (28B) is thicker than walls (26, 34B) that oppose it in camber deformation, so it dominates them in collaboration with the suction side outer wall (32), and the airfoil camber increases. This reduces and relocates a maximum stress area (47) from the suction side outer wall (32) to the suction side inner wall (34B, 72) and the pressure side outer wall (26).

Hydrogeology, distribution, and volume of saline groundwater in the southern midcontinent and adjacent areas of the United States

USGS Publications Warehouse

Osborn, Noël I.; Smith, S. Jerrod; Seger, Christian H.

2013-01-01

The hydrogeology, distribution, and volume of saline water in 22 aquifers in the southern midcontinent of the United States were evaluated to provide information about saline groundwater resources that may be used to reduce dependency on freshwater resources. Those aquifers underlie six States in the southern midcontinent—Arkansas, Kansas, Louisiana, Missouri, Oklahoma, and Texas—and adjacent areas including all or parts of Alabama, Colorado, Florida, Illinois, Kentucky, Mississippi, Nebraska, New Mexico, South Dakota, Tennessee, and Wyoming and some offshore areas of the Gulf of Mexico. Saline waters of the aquifers were evaluated by defining salinity zones; digitizing data, primarily from the Regional Aquifer-System Analysis Program of the U.S. Geological Survey; and computing the volume of saline water in storage. The distribution of saline groundwater in the southern midcontinent is substantially affected by the hydrogeology and groundwater-flow systems of the aquifers. Many of the aquifers in the southern midcontinent are underlain by one or more aquifers, resulting in vertically stacked aquifers containing groundwaters of varying salinity. Saline groundwater is affected by past and present hydrogeologic conditions. Spatial variation of groundwater salinity in the southern midcontinent is controlled primarily by locations of recharge and discharge areas, groundwater-flow paths and residence time, mixing of freshwater and saline water, and interactions with aquifer rocks and sediments. The volume calculations made for the evaluated aquifers in the southern midcontinent indicate that about 39,900 million acre-feet (acre-ft) of saline water is in storage. About 21,600 million acre-ft of the water in storage is slightly to moderately saline (1,000–10,000 milligrams per liter [mg/L] dissolved solids), and about 18,300 million acre-ft is very saline (10,000–35,000 mg/L dissolved solids). The largest volumes of saline water are in the coastal lowlands (about

Wall-ablative laser-driven in-tube accelerator

NASA Astrophysics Data System (ADS)

Sasoh, Akihiro; Suzuki, Shingo; Matsuda, Atsushi

2008-05-01

The laser-driven in-tube accelerator in which the propellant is supplied from laser-ablated gas from the tube wall was developed. Proof-of concept demonstrations of vertical launch were successfully done. The device had a 25mm X 25mm square cross-section; two opposing walls were made of polyacetal and acted as the propellant, the other two acrylic window with guide grooves to the projectile. The upper end of the launch tube was connected to a vacuum chamber of an inner volume of 0.8 m2, in which the initial pressure was set to lower than 20 Pa. With plugging the bottom end of the launch tube, a momentum coupling coefficient exceeding 2.5 mN/W was obtained. Even with the bottom end connected to the same vacuum chamber through a different duct, the projectile was vertical launched successfully, obtaining 0.14 mN/W.

Airborne gamma-ray spectrometer and magnetometer survey, Durango A, Colorado. Final report Volume II A. Detail area

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

Not Available

1983-01-01

This volume contains geology of the Durango A detail area, radioactive mineral occurences in Colorado, and geophysical data interpretation. Eight appendices provide the following: stacked profiles, geologic histograms, geochemical histograms, speed and altitude histograms, geologic statistical tables, geochemical statistical tables, magnetic and ancillary profiles, and test line data.

Shielding synchrotron light sources: Advantages of circular shield walls tunnels

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

Kramer, S. L.; Ghosh, V. J.; Breitfeller, M.

Third generation high brightness light sources are designed to have low emittance and high current beams, which contribute to higher beam loss rates that will be compensated by Top-Off injection. Shielding for these higher loss rates will be critical to protect the projected higher occupancy factors for the users. Top-Off injection requires a full energy injector, which will demand greater consideration of the potential abnormal beam miss-steering and localized losses that could occur. The high energy electron injection beam produce significantly higher neutron component dose to the experimental floor than lower energy injection and ramped operations. High energy neutrons producedmore » in the forward direction from thin target beam losses are a major component of the dose rate outside the shield walls of the tunnel. The convention has been to provide thicker 90° ratchet walls to reduce this dose to the beam line users. We present an alternate circular shield wall design, which naturally and cost effectively increases the path length for this forward radiation in the shield wall and thereby substantially decreasing the dose rate for these beam losses. Here, this shield wall design will greatly reduce the dose rate to the users working near the front end optical components but will challenge the beam line designers to effectively utilize the longer length of beam line penetration in the shield wall. Additional advantages of the circular shield wall tunnel are that it's simpler to construct, allows greater access to the insertion devices and the upstream in tunnel beam line components, as well as reducing the volume of concrete and therefore the cost of the shield wall.« less

Shielding synchrotron light sources: Advantages of circular shield walls tunnels

DOE PAGES

Kramer, S. L.; Ghosh, V. J.; Breitfeller, M.

2016-04-26

Third generation high brightness light sources are designed to have low emittance and high current beams, which contribute to higher beam loss rates that will be compensated by Top-Off injection. Shielding for these higher loss rates will be critical to protect the projected higher occupancy factors for the users. Top-Off injection requires a full energy injector, which will demand greater consideration of the potential abnormal beam miss-steering and localized losses that could occur. The high energy electron injection beam produce significantly higher neutron component dose to the experimental floor than lower energy injection and ramped operations. High energy neutrons producedmore » in the forward direction from thin target beam losses are a major component of the dose rate outside the shield walls of the tunnel. The convention has been to provide thicker 90° ratchet walls to reduce this dose to the beam line users. We present an alternate circular shield wall design, which naturally and cost effectively increases the path length for this forward radiation in the shield wall and thereby substantially decreasing the dose rate for these beam losses. Here, this shield wall design will greatly reduce the dose rate to the users working near the front end optical components but will challenge the beam line designers to effectively utilize the longer length of beam line penetration in the shield wall. Additional advantages of the circular shield wall tunnel are that it's simpler to construct, allows greater access to the insertion devices and the upstream in tunnel beam line components, as well as reducing the volume of concrete and therefore the cost of the shield wall.« less

An economic analysis of four options for dealing with low-volume roads in energy-impacted areas of Texas.

DOT National Transportation Integrated Search

2014-10-01

The Texas A&M Transportation Institute undertook an economic analysis to compare the costs of : maintaining a typical Texas low-volume road in an energy-impacted area in its current state versus widening : and maintaining the road; converting it to a...

Proper Accounting for Surface Area to Solution Volume Ratios in Exaggerated Extractions.

PubMed

Jenke, Dennis R; Rabinow, Barrett E

2017-01-01

When drug products contact plastic manufacturing components, packaging systems, and/or delivery devices, leachables from the plastics can accumulate in the drug product, potentially affecting its key quality attributes. Given practical issues associated with screening drug products for leachables, potential leachables are frequently surfaced as extractables revealed in extraction studies. To facilitate extractables discovery and identification and to shorten extraction times, extraction studies can be exaggerated and/or accelerated. One means of exaggerating an extraction is to increase the test article's extracted surface area to extraction solution volume ratio (SA/V), as it is generally accepted that an extractable's concentration in an extract is proportional to SA/V in a 1 to 1 manner. However, as the relationship between an extractable's concentration and SA/V depends on the extractable's plastic/solvent partition coefficient (k p/l ), the effect of SA/V on the extractable's concentrations can be either under- or over-estimated if a 1 to 1 proportion is used. This article presents the theoretical relationship between SA/V, concentration, and k p/l ; illustrates theory with a case study; and suggests proper exaggeration strategies. LAY ABSTRACT: When drug products are manufactured, stored, or delivered in systems that contain plastics, substances can be leached from the plastics and remain in the drug product, where they might affect the product's key quality attributes. To discover and identify these leached substances, the plastics are extracted under laboratory conditions and the extracts are appropriately tested. To facilitate this process, extracts may be generated under laboratory conditions that exaggerate or accelerate the drug product's clinical conditions of manufacturing or use. The proper use of the ratio of the extracted item's surface area to the volume of the extracting solution as an exaggeration parameter is discussed in this paper. © PDA

Velocity distribution in a turbulent flow near a rough wall

NASA Astrophysics Data System (ADS)

Korsun, A. S.; Pisarevsky, M. I.; Fedoseev, V. N.; Kreps, M. V.

2017-11-01

Velocity distribution in the zone of developed wall turbulence, regardless of the conditions on the wall, is described by the well-known Prandtl logarithmic profile. In this distribution, the constant, that determines the value of the velocity, is determined by the nature of the interaction of the flow with the wall and depends on the viscosity of the fluid, the dynamic velocity, and the parameters of the wall roughness.In extreme cases depending on the ratio between the thickness of the viscous sublayer and the size of the roughness the constant takes on a value that does not depend on viscosity, or leads to a ratio for a smooth wall.It is essential that this logarithmic profile is the result not only of the Prandtl theory, but can be derived from general considerations of the theory of dimensions, and also follows from the condition of local equilibrium of generation and dissipation of turbulent energy in the wall area. This allows us to consider the profile as a universal law of velocity distribution in the wall area of a turbulent flow.The profile approximation up to the maximum speed line with subsequent integration makes possible to obtain the resistance law for channels of simple shape. For channels of complex shape with rough walls, the universal profile can be used to formulate the boundary condition when applied to the calculation of turbulence models.This paper presents an empirical model for determining the constant of the universal logarithmic profile. The zone of roughness is described by a set of parameters and is considered as a porous structure with variable porosity.

Correlation Between Endotracheal Tube Cuff Pressure and Tracheal Wall Pressure Using Air and Saline Filled Cuffs

DTIC Science & Technology

2017-01-31

AFRL-SA-WP-SR-2017-0004 Correlation Between Endotracheal Tube Cuff Pressure and Tracheal Wall Pressure Using Air- and Saline -Filled...Correlation Between Endotracheal Tube Cuff Pressure and Tracheal Wall Pressure Using Air- and Saline -Filled Cuffs 5a. CONTRACT NUMBER FA8650-14...descending from altitude. When using saline in the ETT cuff, TW pressure differences with the 7.5 high-volume, low-pressure cuff and 8.0 TaperGuard

VIEW LOOKING SOUTHWEST INTO LOCK 71. NOTE THE CONCRETE WALL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW LOOKING SOUTHWEST INTO LOCK 71. NOTE THE CONCRETE WALL WITH GATE-VALVED INLETS AT THE BOTTOM, BUILT AT THE LOCATION OF THE FORMER LOCK GATES. THE INLETS CONTROL THE VOLUME OF WATER PASSING THROUGH THE SPILLWAY TO MANAGE THE WATER FLOW TO THE DOWNSTREAM PORTION OF THE CANAL. - New York State Barge Canal, Lockport Locks, Richmond Avenue, Lockport, Niagara County, NY

[Failure of static pulmonary volume measurements in mucoviscidosis].

PubMed

Haluszka, J; Zebrak, J

1984-01-01

With worsening of bronchial obstruction during the course of cystic fibrosis the functional residual capacity (CRF) measured by plethysmography increases progressively. The difference between values of CRF obtained by plethysmography or by Helium dilution increases even more. The difference between the two methods (for CRF) is supposed to show the volume of "trapped"' gas. A similar outcome, although less marked, is observed after physiotherapy. The extent of pulmonary distention and gas trapping is markedly overestimated by plethysmographic measurements, when one considers the anatomical and radiological anomalies. It was recently suggested that the rise in compliance of the walls of the extra-thoracic airways in the presence of bronchial obstruction may lead to an over-estimation of the pulmonary volumes measured by plethysmography. This may be the case during the course of mucoviscidosis, when repeated infections lead to a destruction of the bronchial walls. However, this anomaly does not explain this rise in CRF after mucolytic treatment and postural drainage. The CRF seems to reflect not only the volume of trapper gas in the lung, but equally the failure to equalize the interior pressures of the obstructed airways. In order to appreciate the effects of respiratory physiotherapy, different methods of measuring pulmonary volumes are necessary but the interpretation of the results take account of the complex meterology.

Jetting of a ultrasound contrast microbubble near a rigid wall

NASA Astrophysics Data System (ADS)

Sarkar, Kausik; Mobadersany, Nima

2017-11-01

Micron sized gas-bubbles coated with a stabilizing shell of lipids or proteins, are used as contrast enhancing agents for ultrasound imaging. However, they are increasingly being explored for novel applications in drug delivery through a process called sonoporation, the reversible permeabilization of the cell membrane. Under sufficiently strong acoustic excitations, bubbles form a jet and collapse near a wall. The jetting of free bubbles has been extensively studied by boundary element method (BEM). Here, for the first time, we implemented a rigorous interfacial rheological model of the shell into BEM and investigated the jet formation. The code has been carefully validated against past results. Increasing shell elasticity decreases the maximum bubble volume and the collapse time, while the jet velocity increases. The shear stress on the wall is computed and analyzed. A phase diagram as functions of excitation pressure and wall separation describes jet formation. Effects of shell elasticity and frequency on the phase diagram are investigated. Partially supported by National Science Foundation.

Is orbital volume associated with eyeball and visual cortex volume in humans?

PubMed

Pearce, Eiluned; Bridge, Holly

2013-01-01

In humans orbital volume increases linearly with absolute latitude. Scaling across mammals between visual system components suggests that these larger orbits should translate into larger eyes and visual cortices in high latitude humans. Larger eyes at high latitudes may be required to maintain adequate visual acuity and enhance visual sensitivity under lower light levels. To test the assumption that orbital volume can accurately index eyeball and visual cortex volumes specifically in humans. Structural Magnetic Resonance Imaging (MRI) techniques are employed to measure eye and orbit (n = 88) and brain and visual cortex (n = 99) volumes in living humans. Facial dimensions and foramen magnum area (a proxy for body mass) were also measured. A significant positive linear relationship was found between (i) orbital and eyeball volumes, (ii) eyeball and visual cortex grey matter volumes and (iii) different visual cortical areas, independently of overall brain volume. In humans the components of the visual system scale from orbit to eye to visual cortex volume independently of overall brain size. These findings indicate that orbit volume can index eye and visual cortex volume in humans, suggesting that larger high latitude orbits do translate into larger visual cortices.

Bio-mathematical analysis for the peristaltic flow of single wall carbon nanotubes under the impact of variable viscosity and wall properties.

PubMed

Shahzadi, Iqra; Sadaf, Hina; Nadeem, Sohail; Saleem, Anber

2017-02-01

The main objective of this paper is to study the Bio-mathematical analysis for the peristaltic flow of single wall carbon nanotubes under the impact of variable viscosity and wall properties. The right and the left walls of the curved channel possess sinusoidal wave that is travelling along the outer boundary. The features of the peristaltic motion are determined by using long wavelength and low Reynolds number approximation. Exact solutions are determined for the axial velocity and for the temperature profile. Graphical results have been presented for velocity profile, temperature and stream function for various physical parameters of interest. Symmetry of the curved channel is disturbed for smaller values of the curvature parameter. It is found that the altitude of the velocity profile increases for larger values of variable viscosity parameter for both the cases (pure blood as well as single wall carbon nanotubes). It is detected that velocity profile increases with increasing values of rigidity parameter. It is due to the fact that an increase in rigidity parameter decreases tension in the walls of the blood vessels which speeds up the blood flow for pure blood as well as single wall carbon nanotubes. Increase in Grashof number decreases the fluid velocity. This is due to the reason that viscous forces play a prominent role that's why increase in Grashof number decreases the velocity profile. It is also found that temperature drops for increasing values of nanoparticle volume fraction. Basically, higher thermal conductivity of the nanoparticles plays a key role for quick heat dissipation, and this justifies the use of the single wall carbon nanotubes in different situations as a coolant. Exact solutions are calculated for the temperature and the velocity profile. Symmetry of the curved channel is destroyed due to the curvedness for velocity, temperature and contour plots. Addition of single wall carbon nanotubes shows a decrease in fluid temperature. Trapping

A Caulobacter MreB mutant with irregular cell shape exhibits compensatory widening to maintain a preferred surface area to volume ratio

PubMed Central

Harris, Leigh K.; Dye, Natalie A.; Theriot, Julie A.

2014-01-01

Summary Rod-shaped bacteria typically elongate at a uniform width. To investigate the genetic and physiological determinants involved in this process, we studied a mutation in the morphogenetic protein MreB in Caulobacter crescentus that gives rise to cells with a variable-width phenotype, where cells have regions that are both thinner and wider than wild-type. During growth, individual cells develop a balance of wide and thin regions, and mutant MreB dynamically localizes to poles and thin regions. Surprisingly, the surface area to volume ratio of these irregularly-shaped cells is, on average, very similar to wild-type. We propose that, while mutant MreB localizes to thin regions and promotes rod-like growth there, wide regions develop as a compensatory mechanism, allowing cells to maintain a wild-type-like surface area to volume ratio. To support this model, we have shown that cell widening is abrogated in growth conditions that promote higher surface area to volume ratios, and we have observed individual cells with high ratios return to wild-type levels over several hours by developing wide regions, suggesting that compensation can take place at the level of individual cells. PMID:25266768

Improving Station Performance by Building Isolation Walls in the Tunnel

NASA Astrophysics Data System (ADS)

Jia, Yan; Horn, Nikolaus; Leohardt, Roman

2014-05-01

Conrad Observatory is situated far away from roads and industrial areas on the Trafelberg in Lower Austria. At the end of the seismic tunnel, the main seismic instrument of the Observatory with a station code CONA is located. This station is one of the most important seismic stations in the Austrian Seismic Network (network code OE). The seismic observatory consists of a 145m long gallery and an underground laboratory building with several working areas. About 25 meters away from the station CONA, six temporary seismic stations were implemented for research purposes. Two of them were installed with the same equipment as CONA, while the remaining four stations were set up with digitizers having lower noise and higher resolution (Q330HR) and sensors with the same type (STS-2). In order to prevent possible disturbances by air pressure and temperature fluctuation, three walls were built inside of the tunnel. The first wall is located ca 63 meters from the tunnel entrance, while a set of double walls with a distance of 1.5 meters is placed about 53 meters from the first isolation wall but between the station CONA and the six temporary stations. To assess impact of the isolation walls on noise reduction and detection performance, investigations are conducted in two steps. The first study is carried out by comparing the noise level and detection performance between the station CONA behind the double walls and the stations in front of the double walls for verifying the noise isolation by the double walls. To evaluate the effect of the single wall, station noise level and detection performance were studied by comparing the results before and after the installation of the wall. Results and discussions will be presented. Additional experiment is conducted by filling insulation material inside of the aluminium boxes of the sensors (above and around the sensors). This should help us to determine an optimal insulation of the sensors with respect to pressure and temperature

Reinforcement mechanism of multi-anchor wall with double wall facing

NASA Astrophysics Data System (ADS)

Suzuki, Kouta; Kobayashi, Makoto; Miura, Kinya; Konami, Takeharu; Hayashi, Taketo

2017-10-01

The reinforced soil wall has high seismic performance as generally known. However, the seismic behavior has not been clarified accurately yet, especially on multi-anchor wall with double wall facing. Indefinite behavior of reinforced soil wall during earthquake make us complicated in case with adopting to the abutment, because of arrangement of anchor plate as reinforcement often different according to the width of roads. In this study, a series of centrifuge model tests were carried out to investigate the reinforcement mechanism of multi anchor wall with double wall facing from the perspective of the vertical earth pressure. Several types of reinforce arrangement and rigid wall were applied in order to verify the arch function in the reinforced regions. The test results show unique behavior of vertical earth pressure, which was affected by arch action. All the vertical earth pressure placed behind facing panel, are larger than that of middle part between facing panel despite of friction between backfill and facing panel. Similar results were obtained in case using rigid wall. On the other hands, the vertical earth pressure, which were measured at the 3cm high from bottom of model container, shows larger than that of bottom. This results show the existence of arch action between double walls. In addition, it implies that the wall facing of such soil structure confined the backfill as pseudo wall, which is very reason that the multi anchor wall with double wall facing has high seismic performance.

Retrofitted green roofs and walls and improvements in thermal comfort

NASA Astrophysics Data System (ADS)

Feitosa, Renato Castiglia; Wilkinson, Sara

2017-06-01

Increased urbanization has led to a worsening in the quality of life for many people living in large cities in respect of the urban heat island effect and increases of indoor temperatures in housing and other buildings. A solution may be to retrofit existing environments to their former conditions, with a combination of green infrastructures applied to existing walls and rooftops. Retrofitted green roofs may attenuate housing temperature. However, with tall buildings, facade areas are much larger compared to rooftop areas, the role of green walls in mitigating extreme temperatures is more pronounced. Thus, the combination of green roofs and green walls is expected to promote a better thermal performance in the building envelope. For this purpose, a modular vegetated system is adopted for covering both walls and rooftops. Rather than temperature itself, the heat index, which comprises the combined effect of temperature and relative humidity is used in the evaluation of thermal comfort in small scale experiments performed in Sydney - Australia, where identical timber framed structures prototypes (vegetated and non-vegetated) are compared. The results have shown a different understanding of thermal comfort improvement regarding heat index rather than temperature itself. The combination of green roof and walls has a valid role to play in heat index attenuation.

Localized volume effects for late rectal and anal toxicity after radiotherapy for prostate cancer

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

Peeters, Stephanie T.H.; Lebesque, Joos V.; Heemsbergen, Wilma D.

2006-03-15

Purpose: To identify dosimetric parameters derived from anorectal, rectal, and anal wall dose distributions that correlate with different late gastrointestinal (GI) complications after three-dimensional conformal radiotherapy for prostate cancer. Methods and Materials: In this analysis, 641 patients from a randomized trial (68 Gy vs. 78 Gy) were included. Toxicity was scored with adapted Radiation Therapy Oncology Group/European Organization for the Research and Treatment of Cancer (RTOG/EORTC) criteria and five specific complications. The variables derived from dose-volume histogram of anorectal, rectal, and anal wall were as follows: % receiving {>=}5-70 Gy (V5-V70), maximum dose (D{sub max}), and mean dose (D{sub mean}).more » The anus was defined as the most caudal 3 cm of the anorectum. Statistics were done with multivariate Cox regression models. Median follow-up was 44 months. Results: Anal dosimetric variables were associated with RTOG/EORTC Grade {>=}2 (V5-V40, D{sub mean}) and incontinence (V5-V70, D{sub mean}). Bleeding correlated most strongly with anorectal V55-V65, and stool frequency with anorectal V40 and D{sub mean}. Use of steroids was weakly related to anal variables. No volume effect was seen for RTOG/EORTC Grade {>=}3 and pain/cramps/tenesmus. Conclusion: Different volume effects were found for various late GI complications. Therefore, to evaluate the risk of late GI toxicity, not only intermediate and high doses to the anorectal wall volume should be taken into account, but also the dose to the anal wall.« less

Permanent effects of postnatal administration of beta-adrenergic ligands on the volume of sexually dimorphic nucleus of the preoptic area (SDN-POA) in rats.

PubMed

Izdebska-Straszak, Grazyna; Gubala, Elzbieta; Jedrzejowska-Szypulka, Halina; Klencki, Mariusz; Wiczkowski, Andrzej; Jarzab, Barbara

2006-01-01

beta-adrenergic ligands have been shown to influence sexual differentiation of the brain. In the present study we document that short postnatal treatment with beta-adrenergic agonists or antagonists may permanently reverse the morphological sex of the brain, as judged by the volume of sexually dimorphic nucleus of the preoptic area (SDN-POA). Female rats treated by beta(2)-adrenergic stimulating ligands exhibit an increased, male type SDN-POA volume while male rats treated by beta1-adrenergic antagonists show a decreased, female type of SDN-POA volume. To analyze the volume of SDN-POA of adult rats after postnatal administration of betaadrenergic ligands. From the second day of life, over 5 consecutive days, all the neonates were injected subcutaneously with the following drugs: isoproterenol, salbutamol, metoprolol alprenolol or saline. SDN-POA volumes were estimated planimetrically on serial brain slides. In male rats the mean volume of SDN-POA was 9.97 +/- 1.66 x 10(-3) mm(3), in female rats the respective volume reached 4.02 +/- 1.26 x 10(-3) mm(3) only and was 2.5 times lower, the difference being highly statistically significant. Postnatal administration of isoproterenol remained without effect in male rats but diminished the SDN-POA volume in female rats, thus increasing the sexual dimorphism. The disappearance of sexual dimorphism was noted in rats treated postnatally with salbutamol. This effect was due to the increase in SDN-POA volumes in female rats, up to 9.81 +/- 2.64 x 10(-3) mm(3), the levels approaching the male type of POA differentiation. Postnatal alprenolol treatment influenced the sexual dimorphism of the brain by decreasing the SDN-POA volume reached by adult males. In fact, in rats treated postnatally with alprenolol, the volume of the nucleus reached only 4,44 +/- 1,61 x 10(-3) mm(3), being not statistically different from female nuclei. The effect of metoprolol pretreatment was similar to alprenolol. Male volumes of SDN-POA were restored

Assessment of bronchial wall thickness and lumen diameter in human adults using multi-detector computed tomography: comparison with theoretical models

PubMed Central

Montaudon, M; Desbarats, P; Berger, P; de Dietrich, G; Marthan, R; Laurent, F

2007-01-01

A thickened bronchial wall is the morphological substratum of most diseases of the airway. Theoretical and clinical models of bronchial morphometry have so far focused on bronchial lumen diameter, and bronchial length and angles, mainly assessed from bronchial casts. However, these models do not provide information on bronchial wall thickness. This paper reports in vivo values of cross-sectional wall area, lumen area, wall thickness and lumen diameter in ten healthy subjects as assessed by multi-detector computed tomography. A validated dedicated software package was used to measure these morphometric parameters up to the 14th bronchial generation, with respect to Weibel's model of bronchial morphometry, and up to the 12th according to Boyden's classification. Measured lumen diameters and homothety ratios were compared with theoretical values obtained from previously published studies, and no difference was found when considering dichotomic division of the bronchial tree. Mean wall area, lumen area, wall thickness and lumen diameter were then provided according to bronchial generation order, and mean homothety ratios were computed for wall area, lumen area and wall thickness as well as equations giving the mean value of each parameter for a given bronchial generation with respect to its value in generation 0 (trachea). Multi-detector computed tomography measurements of bronchial morphometric parameters may help to improve our knowledge of bronchial anatomy in vivo, our understanding of the pathophysiology of bronchial diseases and the evaluation of pharmacological effects on the bronchial wall. PMID:17919291

Space Radar Image of Great Wall of China

NASA Image and Video Library

1999-04-15

These radar images show two segments of the Great Wall of China in a desert region of north-central China, about 700 kilometers (434 miles) west of Beijing. The wall appears as a thin orange band, running from the top to the bottom of the left image, and from the middle upper-left to the lower-right of the right image. These segments of the Great Wall were constructed in the 15th century, during the Ming Dynasty. The wall is between 5 and 8 meters high (16 to 26 feet) in these areas. The entire wall is about 3,000 kilometers (1,864 miles) long and about 150 kilometers (93 miles) of the wall appear in these two images. The wall is easily detected from space by radar because its steep, smooth sides provide a prominent surface for reflection of the radar beam. Near the center of the left image, two dry lake beds have been developed for salt extraction. Rectangular patterns in both images indicate agricultural development, primarily wheat fields. The images were acquired by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) onboard the space shuttle Endeavour on April 10, 1994. SIR-C/X-SAR, a joint mission of the German, Italian and the United States space agencies, is part of NASA's Mission to Planet Earth. The left image is centered at 37.7 degrees North latitude and 107.5 degrees East longitude. The right image is centered at 37.5 degrees North latitude and 108.1 degrees East longitude. North is toward the upper right. Each area shown measures 25 kilometers by 75 kilometers (15.5 miles by 45.5 miles). The colors in the image are assigned to different frequencies and polarizations of the radar as follows: red is L-band horizontally transmitted, horizontally received; green is L-band horizontally transmitted, vertically received; blue is C-band horizontally transmitted, vertically received. http://photojournal.jpl.nasa.gov/catalog/PIA01794

Simulation and analysis of collapsing vapor-bubble clusters with special emphasis on potentially erosive impact loads at walls

NASA Astrophysics Data System (ADS)

Ogloblina, Daria; Schmidt, Steffen J.; Adams, Nikolaus A.

2018-06-01

Cavitation is a process where a liquid evaporates due to a pressure drop and re-condenses violently. Noise, material erosion and altered system dynamics characterize for such a process for which shock waves, rarefaction waves and vapor generation are typical phenomena. The current paper presents novel results for collapsing vapour-bubble clusters in a liquid environment close to a wall obtained by computational fluid mechanics (CFD) simulations. The driving pressure initially is 10 MPa in the liquid. Computations are carried out by using a fully compressible single-fluid flow model in combination with a conservative finite volume method (FVM). The investigated bubble clusters (referred to as "clouds") differ by their initial vapor volume fractions, initial stand-off distances to the wall and by initial bubble radii. The effects of collapse focusing due to bubble-bubble interaction are analysed by investigating the intensities and positions of individual bubble collapses, as well as by the resulting shock-induced pressure field at the wall. Stronger interaction of the bubbles leads to an intensification of the collapse strength for individual bubbles, collapse focusing towards the center of the cloud and enhanced re-evaporation. The obtained results reveal collapse features which are common for all cases, as well as case-specific differences during collapse-rebound cycles. Simultaneous measurements of maximum pressures at the wall and within the flow field and of the vapor volume evolution show that not only the primary collapse but also subsequent collapses are potentially relevant for erosion.

Static allometry of unicellular green algae: scaling of cellular surface area and volume in the genus Micrasterias (Desmidiales).

PubMed

Neustupa, J

2016-02-01

The surface area-to-volume ratio of cells is one of the key factors affecting fundamental biological processes and, thus, fitness of unicellular organisms. One of the general models for allometric increase in surface-to-volume scaling involves fractal-like elaboration of cellular surfaces. However, specific data illustrating this pattern in natural populations of the unicellular organisms have not previously been available. This study shows that unicellular green algae of the genus Micrasterias (Desmidiales) have positive allometric surface-to-volume scaling caused by changes in morphology of individual species, especially in the degree of cell lobulation. This allometric pattern was also detected within most of the cultured and natural populations analysed. Values of the allometric S:V scaling within individual populations were closely correlated to the phylogenetic structure of the clade. In addition, they were related to species-specific cellular morphology. Individual populations differed in their allometric patterns, and their position in the allometric space was strongly correlated with the degree of allometric S:V scaling. This result illustrates that allometric shape patterns are an important correlate of the capacity of individual populations to compensate for increases in their cell volumes by increasing the surface area. However, variation in allometric patterns was not associated with phylogenetic structure. This indicates that the position of the populations in the allometric space was not evolutionarily conserved and might be influenced by environmental factors. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Electromagnetic approaches to wall characterization, wall mitigation, and antenna design for through-the-wall radar systems

NASA Astrophysics Data System (ADS)

Thajudeen, Christopher

Through-the-wall imaging (TWI) is a topic of current interest due to its wide range of public safety, law enforcement, and defense applications. Among the various available technologies such as, acoustic, thermal, and optical imaging, which can be employed to sense and image targets of interest, electromagnetic (EM) imaging, in the microwave frequency bands, is the most widely utilized technology and has been at the forefront of research in recent years. The primary objectives for any Through-the-Wall Radar Imaging (TWRI) system are to obtain a layout of the building and/or inner rooms, detect if there are targets of interest including humans or weapons, determine if there are countermeasures being employed to further obscure the contents of a building or room of interest, and finally to classify the detected targets. Unlike conventional radar scenarios, the presence of walls, made of common construction materials such as brick, drywall, plywood, cinder block, and solid concrete, adversely affects the ability of any conventional imaging technique to properly image targets enclosed within building structures as the propagation through the wall can induce shadowing effects on targets of interest which may result in image degradation, errors in target localization, and even complete target masking. For many applications of TWR systems, the wall ringing signals are strong enough to mask the returns from targets not located a sufficient distance behind the wall, beyond the distance of the wall ringing, and thus without proper wall mitigation, target detection becomes extremely difficult. The results presented in this thesis focus on the development of wall parameter estimation, and intra-wall and wall-type characterization techniques for use in both the time and frequency domains as well as analysis of these techniques under various real world scenarios such as reduced system bandwidth scenarios, various wall backing scenarios, the case of inhomogeneous walls, presence

Fiber Volume Fraction Influence on Fiber Compaction in Tapered Resin Injection Pultrusion Manufacturing

NASA Astrophysics Data System (ADS)

Masuram, N. B.; Roux, J. A.; Jeswani, A. L.

2016-06-01

Liquid resin is injected into the tapered injection chamber through the injection slots to completely wetout the fiber reinforcements in a resin injection pultrusion process. As the resin penetrates through the fibers, the resin also pushes the fibers away from the wall towards the centerline causing compaction of the fiber reinforcements. The fibers are squeezed together due to compaction, making resin penetration more difficult; thus higher resin injection pressures are required to effectively penetrate through the fibers and achieve complete wetout. Fiber volume fraction in the final pultruded composite is a key to decide the mechanical and/or chemical properties of the composite. If the fiber volume fraction is too high, more fibers are squeezed together creating a fiber lean region near the wall and fiber rich region away from the wall. Also, the design of the injection chamber significantly affects the minimum injection pressure required to completely wet the fibers. A tapered injection chamber is considered such that wetout occurs at lower injection pressures due to the taper angle of the injection chamber. In this study, the effect of fiber volume fraction on the fiber reinforcement compaction and complete fiber wetout for a tapered injection chamber is investigated.

On streak spacing in wall-bounded turbulent flows

NASA Technical Reports Server (NTRS)

Hamilton, James M.; Kim, John J.

1993-01-01

The present study is a continuation of the examination by Hamilton et al. of the regeneration mechanisms of near-wall turbulence and an attempt to investigate the conjecture of Waleffe et al. The basis of this study is an extension of the 'minimal channel' approach of Jimenez and Moin that emphasizes the near-wall region and reduces the complexity of the turbulent flow by considering a plane Couette flow of near minimum Reynolds number and stream-wise and span-wise extent. Reduction of the flow Reynolds number to the minimum value which will allow turbulence to be sustained has the effect of reducing the ratio of the largest scales to the smallest scales or, equivalently, of causing the near-wall region to fill more of the area between the channel walls. A plane Couette flow was chosen for study since this type of flow has a mean shear of a single sign, and at low Reynolds numbers, the two wall regions are found to share a single set of structures.

Measurements of Intra‐Aortic Balloon Wall Movement During Inflation and Deflation: Effects of Angulation

PubMed Central

Bruti, Gianpaolo; Kolyva, Christina; Pepper, John R.

2015-01-01

Abstract The intra‐aortic balloon pump (IABP) is a ventricular assist device that is used with a broad range of pre‐, intra‐, and postoperative patients undergoing cardiac surgery. Although the clinical efficacy of the IABP is well documented, the question of reduced efficacy when patients are nursed in the semi‐recumbent position remains outstanding. The aim of the present work is therefore to investigate the underlying mechanics responsible for the loss of IABP performance when operated at an angle to the horizontal. Simultaneous recordings of balloon wall movement, providing an estimate of its diameter (D), and fluid pressure were taken at three sites along the intra‐aortic balloon (IAB) at 0 and 45°. Flow rate, used for the calculation of displaced volume, was also recorded distal to the tip of the balloon. An in vitro experimental setup was used, featuring physiological impedances on either side of the IAB ends. IAB inflation at an angle of 45° showed that D increases at the tip of the IAB first, presenting a resistance to the flow displaced away from the tip of the balloon. The duration of inflation decreased by 15.5%, the inflation pressure pulse decreased by 9.6%, and volume decreased by 2.5%. Similarly, changing the position of the balloon from 0 to 45°, the balloon deflation became slower by 35%, deflation pressure pulse decreased by 14.7%, and volume suctioned was decreased by 15.2%. IAB wall movement showed that operating at 45° results in slower deflation compared with 0°. Slow wall movement, and changes in inflation and deflation onsets, result in a decreased volume displacement and pressure pulse generation. Operating the balloon at an angle to the horizontal, which is the preferred nursing position in intensive care units, results in reduced IAB inflation and deflation performance, possibly compromising its clinical benefits. PMID:25959284

Moisture Management of High-R Walls (Fact Sheet)

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

None, None

2013-12-01

The following report explains the moisture-related concerns for High R-value wall assemblies and discusses past Building America research work that informs this study. Hygrothermal simulations were prepared for several common approaches to High R-value wall construction in six cities (Houston, Atlanta, Seattle, St. Louis, Chicago, and International Falls) representing a range of climate zones (2, 3, 4C, 4, 5A, and 7, respectively). The simulations are informed by experience gained from past research in this area and validated by field measurement and forensic experience. The modeling program was developed to assess the moisture durability of the wall assemblies based on threemore » primary sources of moisture: construction moisture, air leakage condensation, and bulk water leakage. The peak annual moisture content of the wood based exterior sheathing was used to comparatively analyze the response to the moisture loads for each of the walls in each given city. Walls which experienced sheathing moisture contents between 20% and 28% were identified as risky, whereas those exceeding 28% were identified as very high risk. All of the wall assemblies perform well under idealized conditions. However, only the walls with exterior insulation, or cavity insulation which provides a hygrothermal function similar to exterior insulation, perform adequately when exposed to moisture loads. Walls with only cavity insulation are particularly susceptible to air leakage condensation. None of the walls performed well when a precipitation based bulk water leak was introduced to the backside of the sheathing, emphasizing the importance of proper flashing details.« less

A scenario and forecast model for Gulf of Mexico hypoxic area and volume

USGS Publications Warehouse

Scavia, Donald; Evans, Mary Anne; Obenour, Daniel R.

2013-01-01

For almost three decades, the relative size of the hypoxic region on the Louisiana-Texas continental shelf has drawn scientific and policy attention. During that time, both simple and complex models have been used to explore hypoxia dynamics and to provide management guidance relating the size of the hypoxic zone to key drivers. Throughout much of that development, analyses had to accommodate an apparent change in hypoxic sensitivity to loads and often cull observations due to anomalous meteorological conditions. Here, we describe an adaptation of our earlier, simple biophysical model, calibrated to revised hypoxic area estimates and new hypoxic volume estimates through Bayesian estimation. This application eliminates the need to cull observations and provides revised hypoxic extent estimates with uncertainties, corresponding to different nutrient loading reduction scenarios. We compare guidance from this model application, suggesting an approximately 62% nutrient loading reduction is required to reduce Gulf hypoxia to the Action Plan goal of 5,000 km2, to that of previous applications. In addition, we describe for the first time, the corresponding response of hypoxic volume. We also analyze model results to test for increasing system sensitivity to hypoxia formation, but find no strong evidence of such change.

Right Ventricular Tissue Doppler Assessment in Space During Circulating Volume Modification using the Braslet-M Device

NASA Technical Reports Server (NTRS)

Hamilton, D. R.; Sargsyan, A. E.; Fincke, E. M.; Magnus, S. H.; Lonchakov, Y. V.; Alferova, I. V.; Dulchavsky, S. A.; Ebert, D.; Garcia, K.; Martin, D.;

Noninvasive detection of coronary artery wall thickening with age in healthy subjects using high resolution MRI with beat-to-beat respiratory motion correction.

PubMed

Scott, Andrew D; Keegan, Jennifer; Mohiaddin, Raad H; Firmin, David N

2011-10-01

To demonstrate coronary artery wall thickening with age in a small healthy cohort using a highly efficient, reliable, and reproducible high-resolution MR technique. A 3D cross-sectional MR vessel wall images (0.7 × 0.7 × 3 mm resolution) with retrospective beat-to-beat respiratory motion correction (B2B-RMC) were obtained in the proximal right coronary artery of 21 healthy subjects (age, 22-62 years) with no known cardiovascular disease. Lumen and outer wall (lumen + vessel wall) areas were measured in one central slice from each subject and average wall thickness and wall area/outer wall area ratio (W/OW) calculated. Imaging was successful in 18 (86%) subjects with average respiratory efficiency 99.3 ± 1.7%. Coronary vessel wall thickness and W/OW significantly correlate with subject age, increasing by 0.088 mm and 0.031 per decade respectively (R = 0.53, P = 0.024 and R = 0.48, P = 0.046). No relationship was found between lumen area and vessel wall thickness (P = NS), but outer wall area increased significantly with vessel wall thickness at 19 mm(2) per mm (P = 0.046). This is consistent with outward vessel wall remodeling. Despite the small size of our healthy cohort, using high-resolution MR imaging and B2B-RMC, we have demonstrated increasing coronary vessel wall thickness and W/OW with age. The results obtained are consistent with outward vessel wall remodeling. Copyright © 2011 Wiley-Liss, Inc.

Quantification and Statistical Analysis Methods for Vessel Wall Components from Stained Images with Masson's Trichrome

PubMed Central

Hernández-Morera, Pablo; Castaño-González, Irene; Travieso-González, Carlos M.; Mompeó-Corredera, Blanca; Ortega-Santana, Francisco

2016-01-01

Purpose To develop a digital image processing method to quantify structural components (smooth muscle fibers and extracellular matrix) in the vessel wall stained with Masson’s trichrome, and a statistical method suitable for small sample sizes to analyze the results previously obtained. Methods The quantification method comprises two stages. The pre-processing stage improves tissue image appearance and the vessel wall area is delimited. In the feature extraction stage, the vessel wall components are segmented by grouping pixels with a similar color. The area of each component is calculated by normalizing the number of pixels of each group by the vessel wall area. Statistical analyses are implemented by permutation tests, based on resampling without replacement from the set of the observed data to obtain a sampling distribution of an estimator. The implementation can be parallelized on a multicore machine to reduce execution time. Results The methods have been tested on 48 vessel wall samples of the internal saphenous vein stained with Masson’s trichrome. The results show that the segmented areas are consistent with the perception of a team of doctors and demonstrate good correlation between the expert judgments and the measured parameters for evaluating vessel wall changes. Conclusion The proposed methodology offers a powerful tool to quantify some components of the vessel wall. It is more objective, sensitive and accurate than the biochemical and qualitative methods traditionally used. The permutation tests are suitable statistical techniques to analyze the numerical measurements obtained when the underlying assumptions of the other statistical techniques are not met. PMID:26761643

Wind tunnels with adapted walls for reducing wall interference

NASA Technical Reports Server (NTRS)

Ganzer, U.

1979-01-01

The basic principle of adaptable wind tunnel walls is explained. First results of an investigation carried out at the Aero-Space Institute of Berlin Technical University are presented for two dimensional flexible walls and a NACA 0012 airfoil. With five examples exhibiting very different flow conditions it is demonstrated that it is possible to reduce wall interference and to avoid blockage at transonic speeds by wall adaptation.

Height-related scaling of phloem anatomy and the evolution of sieve element end wall types in woody plants.

PubMed

Liesche, Johannes; Pace, Marcelo R; Xu, Qiyu; Li, Yongqing; Chen, Shaolin

2017-04-01

In the sieve elements (SEs) of the phloem, carbohydrates are transported throughout the whole plant from their site of production to sites of consumption or storage. SE structure, especially of the pore-rich end walls, has a direct effect on translocation efficiency. Differences in pore size and other features were interpreted as an evolutionary trend towards reduced hydraulic resistance. However, this has never been confirmed. Anatomical data of 447 species of woody angiosperms and gymnosperms were used for a phylogenetic analysis of end wall types, calculation of hydraulic resistance and correlation analysis with morphological and physiological variables. end wall types were defined according to pore arrangement: either grouped into a single area (simple) or into multiple areas along the end wall (compound). Convergent evolution of end wall types was demonstrated in woody angiosperms. In addition, an optimization of end wall resistance with plant height was discovered, but found to be independent of end wall type. While physiological factors also showed no correlation with end wall types, the number of sieve areas per end wall was found to scale with SE length. The results exclude the minimization of hydraulic resistance as evolutionary driver of different end wall types, contradicting this long-standing assumption. Instead, end wall type might depend on SE length. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Universal Scaling Laws for Dense Particle Suspensions in Turbulent Wall-Bounded Flows.

PubMed

Costa, Pedro; Picano, Francesco; Brandt, Luca; Breugem, Wim-Paul

2016-09-23

The macroscopic behavior of dense suspensions of neutrally buoyant spheres in turbulent plane channel flow is examined. We show that particles larger than the smallest turbulence scales cause the suspension to deviate from the continuum limit in which its dynamics is well described by an effective suspension viscosity. This deviation is caused by the formation of a particle layer close to the wall with significant slip velocity. By assuming two distinct transport mechanisms in the near-wall layer and the turbulence in the bulk, we define an effective wall location such that the flow in the bulk can still be accurately described by an effective suspension viscosity. We thus propose scaling laws for the mean velocity profile of the suspension flow, together with a master equation able to predict the increase in drag as a function of the particle size and volume fraction.

Is orbital volume associated with eyeball and visual cortex volume in humans?

PubMed Central

Pearce, Eiluned; Bridge, Holly

2013-01-01

Background In humans orbital volume increases linearly with absolute latitude. Scaling across mammals between visual system components suggests that these larger orbits should translate into larger eyes and visual cortices in high latitude humans. Larger eyes at high latitudes may be required to maintain adequate visual acuity and enhance visual sensitivity under lower light levels. Aim To test the assumption that orbital volume can accurately index eyeball and visual cortex volumes specifically in humans. Subjects & Methods Structural Magnetic Resonance Imaging (MRI) techniques are employed to measure eye and orbit (N=88), and brain and visual cortex (N=99) volumes in living humans. Facial dimensions and foramen magnum area (a proxy for body mass) were also measured. Results A significant positive linear relationship was found between (i) orbital and eyeball volumes, (ii) eyeball and visual cortex grey matter volumes, (iii) different visual cortical areas, independently of overall brain volume. Conclusion In humans the components of the visual system scale from orbit to eye to visual cortex volume independently of overall brain size. These findings indicate that orbit volume can index eye and visual cortex volume in humans, suggesting that larger high latitude orbits do translate into larger visual cortices. PMID:23879766

Inverse measurement of wall pressure field in flexible-wall wind tunnels using global wall deformation data

NASA Astrophysics Data System (ADS)

Brown, Kenneth; Brown, Julian; Patil, Mayuresh; Devenport, William

2018-02-01

The Kevlar-wall anechoic wind tunnel offers great value to the aeroacoustics research community, affording the capability to make simultaneous aeroacoustic and aerodynamic measurements. While the aeroacoustic potential of the Kevlar-wall test section is already being leveraged, the aerodynamic capability of these test sections is still to be fully realized. The flexibility of the Kevlar walls suggests the possibility that the internal test section flow may be characterized by precisely measuring small deflections of the flexible walls. Treating the Kevlar fabric walls as tensioned membranes with known pre-tension and material properties, an inverse stress problem arises where the pressure distribution over the wall is sought as a function of the measured wall deflection. Experimental wall deformations produced by the wind loading of an airfoil model are measured using digital image correlation and subsequently projected onto polynomial basis functions which have been formulated to mitigate the impact of measurement noise based on a finite-element study. Inserting analytic derivatives of the basis functions into the equilibrium relations for a membrane, full-field pressure distributions across the Kevlar walls are computed. These inversely calculated pressures, after being validated against an independent measurement technique, can then be integrated along the length of the test section to give the sectional lift of the airfoil. Notably, these first-time results are achieved with a non-contact technique and in an anechoic environment.

Stroke Volume estimation using aortic pressure measurements and aortic cross sectional area: Proof of concept.

PubMed

Kamoi, S; Pretty, C G; Chiew, Y S; Pironet, A; Davidson, S; Desaive, T; Shaw, G M; Chase, J G

2015-08-01

Accurate Stroke Volume (SV) monitoring is essential for patient with cardiovascular dysfunction patients. However, direct SV measurements are not clinically feasible due to the highly invasive nature of measurement devices. Current devices for indirect monitoring of SV are shown to be inaccurate during sudden hemodynamic changes. This paper presents a novel SV estimation using readily available aortic pressure measurements and aortic cross sectional area, using data from a porcine experiment where medical interventions such as fluid replacement, dobutamine infusions, and recruitment maneuvers induced SV changes in a pig with circulatory shock. Measurement of left ventricular volume, proximal aortic pressure, and descending aortic pressure waveforms were made simultaneously during the experiment. From measured data, proximal aortic pressure was separated into reservoir and excess pressures. Beat-to-beat aortic characteristic impedance values were calculated using both aortic pressure measurements and an estimate of the aortic cross sectional area. SV was estimated using the calculated aortic characteristic impedance and excess component of the proximal aorta. The median difference between directly measured SV and estimated SV was -1.4ml with 95% limit of agreement +/- 6.6ml. This method demonstrates that SV can be accurately captured beat-to-beat during sudden changes in hemodynamic state. This novel SV estimation could enable improved cardiac and circulatory treatment in the critical care environment by titrating treatment to the effect on SV.

Groundwater contaminant plume maps and volumes, 100-K and 100-N Areas, Hanford Site, Washington

USGS Publications Warehouse

Johnson, Kenneth H.

2016-09-27

extents are shown graphically and in tabular form for comparison to previous estimates. Plume data also were interpolated to a finer grid (10 × 10 m) for some processing, particularly to estimate volumes of contaminated groundwater. However, hydrogeologic transport modeling was not considered for the interpolation. The compilation of plume extents for each contaminant also allowed estimates of overlap of the plumes or areas with more than one contaminant above regulatory standards.A mapping of saturated aquifer thickness also was derived across the 100-K and 100–N study area, based on the vertical difference between the groundwater level (water table) at the top and the altitude of the top of the Ringold Upper Mud geologic unit, considered the bottom of the uppermost unconfined aquifer. Saturated thickness was calculated for each cell in the finer (10 × 10 m) grid. The summation of the cells’ saturated thickness values within each polygon of plume regulatory exceedance provided an estimate of the total volume of contaminated aquifer, and the results also were checked using a SURFER® volumetric integration procedure. The total volume of contaminated groundwater in each plume was derived by multiplying the aquifer saturated thickness volume by a locally representative value of porosity (0.3).Estimates of the uncertainty of the plume delineation also are presented. “Upper limit” plume delineations were calculated for each contaminant using the same procedure as the “average” plume extent except with values at each well that are set at a 95-percent upper confidence limit around the log-normally transformed mean concentrations, based on the standard error for the distribution of the mean value in that well; “lower limit” plumes are calculated at a 5-percent confidence limit around the geometric mean. These upper- and lower-limit estimates are considered unrealistic because the statistics were increased or decreased at each well simultaneously and were not

Cell wall staining with Trypan blue enables quantitative analysis of morphological changes in yeast cells.

PubMed

Liesche, Johannes; Marek, Magdalena; Günther-Pomorski, Thomas

2015-01-01

Yeast cells are protected by a cell wall that plays an important role in the exchange of substances with the environment. The cell wall structure is dynamic and can adapt to different physiological states or environmental conditions. For the investigation of morphological changes, selective staining with fluorescent dyes is a valuable tool. Furthermore, cell wall staining is used to facilitate sub-cellular localization experiments with fluorescently-labeled proteins and the detection of yeast cells in non-fungal host tissues. Here, we report staining of Saccharomyces cerevisiae cell wall with Trypan Blue, which emits strong red fluorescence upon binding to chitin and yeast glucan; thereby, it facilitates cell wall analysis by confocal and super-resolution microscopy. The staining pattern of Trypan Blue was similar to that of the widely used UV-excitable, blue fluorescent cell wall stain Calcofluor White. Trypan Blue staining facilitated quantification of cell size and cell wall volume when utilizing the optical sectioning capacity of a confocal microscope. This enabled the quantification of morphological changes during growth under anaerobic conditions and in the presence of chemicals, demonstrating the potential of this approach for morphological investigations or screening assays.

Nucleon axial charge in (2+1)-flavor dynamical-lattice QCD with domain-wall fermions.

PubMed

Yamazaki, T; Aoki, Y; Blum, T; Lin, H W; Lin, M F; Ohta, S; Sasaki, S; Tweedie, R J; Zanotti, J M

2008-05-02

We present results for the nucleon axial charge g{A} at a fixed lattice spacing of 1/a=1.73(3) GeV using 2+1 flavors of domain wall fermions on size 16;{3} x 32 and 24;{3} x 64 lattices (L=1.8 and 2.7 fm) with length 16 in the fifth dimension. The length of the Monte Carlo trajectory at the lightest m_{pi} is 7360 units, including 900 for thermalization. We find finite volume effects are larger than the pion mass dependence at m{pi}=330 MeV. We also find a scaling with the single variable m{pi}L which can also be seen in previous two-flavor domain wall and Wilson fermion calculations. Using this scaling to eliminate the finite-volume effect, we obtain g{A}=1.20(6)(4) at the physical pion mass, m_{pi}=135 MeV, where the first and second errors are statistical and systematic. The observed finite-volume scaling also appears in similar quenched simulations, but disappear when V>or=(2.4 fm);{3}. We argue this is a dynamical quark effect.

DETAIL OF THE INTERIOR WALL VENTILATION BAND FROM THE MAIN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

DETAIL OF THE INTERIOR WALL VENTILATION BAND FROM THE MAIN GYMNASIUM AREA TO THE LOCKER ROOM AREA. VIEW FACING WEST - U.S. Naval Base, Pearl Harbor, Gymnasium Building, North Waterfront & Pierce Street near Berth S-13, Pearl City, Honolulu County, HI

Structure, function, and biosynthesis of plant cell walls: proceedings of the seventh annual symposium in botany

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

Dugger, W.M.; Bartnicki-Garcia, S.

Papers in the following areas were included in these symposium proceedings: (1) cell wall chemistry and biosynthesis; (2) cell wall hydrolysis and associated physiology; (3) cellular events associated with cell wall biosynthesis; and (4) interactions of plant cell walls with pathogens and related responses. Papers have been individually abstracted for the data base. (ACR)

ETR BUILDING, TRA642, INTERIOR. BASEMENT. CORRIDOR ALONG WEST WALL OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR BUILDING, TRA-642, INTERIOR. BASEMENT. CORRIDOR ALONG WEST WALL OF BUILDING, WHICH IS AT RIGHT OF VIEW. AUDIO ALARM IS ALONG WALL AT RIGHT. CAMERA FACES SOUTH. INL NEGATIVE NO. HD46-30-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Spontaneous Behaviors and Wall-Curvature Lead to Apparent Wall Preference in Planarian.

PubMed

Akiyama, Yoshitaro; Agata, Kiyokazu; Inoue, Takeshi

2015-01-01

The planarian Dugesia japonica tends to stay near the walls of its breeding containers and experimental dishes in the laboratory, a phenomenon called "wall preference". This behavior is thought to be important for environmental adaptation, such as hiding by planarians in nature. However, the mechanisms regulating wall-preference behavior are not well understood, since this behavior occurs in the absence of any particular stimulation. Here we show the mechanisms of wall-preference behavior. Surprisingly, planarian wall-preference behavior was also shown even by the head alone and by headless planarians. These results indicate that planarian "wall-preference" behavior only appears to be a "preference" behavior, and is actually an outcome of spontaneous behaviors, rather than of brain function. We found that in the absence of environmental cues planarians moved basically straight ahead until they reached a wall, and that after reaching a wall, they changed their direction of movement to one tangential to the wall, suggesting that this spontaneous behavior may play a critical role in the wall preference. When we tested another spontaneous behavior, the wigwag movement of the planarian head, using computer simulation with various wigwag angles and wigwag intervals, large wigwag angle and short wigwag interval reduced wall-preference behavior. This indicated that wigwag movement may determine the probability of staying near the wall or leaving the wall. Furthermore, in accord with this simulation, when we tested planarian wall-preference behavior using several assay fields with different curvature of the wall, we found that concavity and sharp curvature of walls negatively impacted wall preference by affecting the permissible angle of the wigwag movement. Together, these results indicate that planarian wall preference may be involuntarily caused by the combination of two spontaneous planarian behaviors: moving straight ahead until reaching a wall and then moving along it

Volume and contact surface area analysis of bony tunnels in single and double bundle anterior cruciate ligament reconstruction using autograft tendons: in vivo three-dimensional imaging analysis.

PubMed

Yang, Jae-Hyuk; Chang, Minho; Kwak, Dai-Soon; Wang, Joon Ho

2014-09-01

Regarding reconstruction surgery of the anterior cruciate ligament (ACL), there is still a debate whether to perform a single bundle (SB) or double bundle (DB) reconstruction. The purpose of this study was to analyze and compare the volume and surface area of femoral and tibial tunnels during transtibial SB versus transportal DB ACL reconstruction. A consecutive series of 26 patients who underwent trantibial SB ACL reconstruction and 27 patients with transportal DB ACL reconstruction using hamstring autograft from January 2010 to October 2010 were included in this study. Three-dimensional computed tomography (3D-CT) was taken within one week after operation. The CT bone images were segmented with use of Mimics software v14.0. The obtained digital images were then imported in the commercial package Geomagic Studio v10.0 and SketchUp Pro v8.0 for processing. The femoral and tibial tunnel lengths, diameters, volumes and surface areas were evaluated. A comparison between the two groups was performed using the independent-samples t-test. A p-value less than the significance value of 5% (p < 0.05) was considered statistically significant. Regarding femur tunnels, a significant difference was not found between the tunnel volume for SB technique (1,496.51 ± 396.72 mm(3)) and the total tunnel volume for DB technique (1,593.81 ± 469.42 mm(3); p = 0.366). However, the total surface area for femoral tunnels was larger in DB technique (919.65 ± 201.79 mm(2)) compared to SB technique (810.02 ± 117.98 mm(2); p = 0.004). For tibia tunnels, there was a significant difference between tunnel volume for the SB technique (2,070.43 ± 565.07 mm(3)) and the total tunnel volume for the DB technique (2,681.93 ± 668.09 mm(3); p ≤ 0.001). The tibial tunnel surface area for the SB technique (958.84 ± 147.50 mm(2)) was smaller than the total tunnel surface area for the DB technique (1,493.31 ± 220.79 mm(2); p ≤ 0.001). Although the total femoral tunnel volume was similar between two

Influence of wall plasma on microwave frequency and power in relativistic backward wave oscillator

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

Sun, Jun; Cao, Yibing; Teng, Yan

2015-07-15

The RF breakdown of the slow wave structure (SWS), which will lead to the generation of the wall plasma, is an important cause for pulse shortening in relativistic backward wave oscillators. Although many researchers have performed profitable studies about this issue, the influence mechanism of this factor on the microwave generation still remains not-so-clear. This paper simplifies the wall plasma with an “effective” permittivity and researches its influence on the microwave frequency and power. The dispersion relation of the SWS demonstrates that the introduction of the wall plasma will move the dispersion curves upward to some extent, which is confirmedmore » by particle-in-cell (PIC) simulations and experiments. The plasma density and volume mainly affect the dispersion relation at the upper and lower frequency limits of each mode, respectively. Meanwhile, PIC simulations show that even though no direct power absorption exists since the wall plasma is assumed to be static, the introduction of the wall plasma may also lead to the decrease in microwave power by changing the electrodynamic property of the SWS.« less

Elevated peripheral cytokines characterize a subgroup of people with schizophrenia displaying poor verbal fluency and reduced Broca's area volume

PubMed Central

Fillman, S G; Weickert, T W; Lenroot, R K; Catts, S V; Bruggemann, J M; Catts, V S; Weickert, C S

2016-01-01

Previous studies on schizophrenia have detected elevated cytokines in both brain and blood, suggesting neuroinflammation may contribute to the pathophysiology in some cases. We aimed to determine the extent to which elevated peripheral cytokine messenger RNA (mRNA) expression: (1) characterizes a subgroup of people with schizophrenia and (2) shows a relationship to cognition, brain volume and/or symptoms. Forty-three outpatients with schizophrenia or schizoaffective disorder and matched healthy controls were assessed for peripheral cytokine mRNAs (interleukin (IL)-1β, IL-2, IL-6, IL-8 and IL-18), intelligence quotient, memory and verbal fluency, symptom severity and cortical brain volumes integral to language (that is, Broca's and Wernicke's areas). IL-1β mRNA levels were 28% increased in schizophrenia compared with controls (t(82)=2.64, P<0.01). Using a two-step clustering procedure, we identified a subgroup of people displaying relatively elevated cytokine mRNA levels (17/43 people with schizophrenia and 9/42 controls). Individuals with schizophrenia in the elevated cytokine subgroup performed significantly worse than the low-cytokine subgroup on verbal fluency (F(1,40)=15.7, P<0.001). There was a 17% volume reduction of the left pars opercularis (POp) (Broca's area) in patients with elevated cytokines compared with patients with lower cytokines (F(1,29)=9.41, P=0.005). Negative linear relationships between IL-1β mRNA levels and both verbal fluency and left POp volume were found in schizophrenia. This study is among the first to link blood biomarkers of inflammation with both cognitive deficits and brain volume reductions in people with schizophrenia, supporting that those with elevated cytokines represent a neurobiologically meaningful subgroup. These findings raise the possibility that targeted anti-inflammatory treatments may ameliorate cognitive and brain morphological abnormalities in some people with schizophrenia. PMID:26194183

The effect of variable size posterior wall acetabular fractures on contact characteristics of the hip joint.

PubMed

Olson, S A; Bay, B K; Pollak, A N; Sharkey, N A; Lee, T

1996-01-01

The indications for open reduction and internal fixation of posterior wall acetabular fractures associated with a clinically stable hip joint are unclear. In previous work a large posterior wall defect (27% articular surface area) resulted in significant alteration of load transmission across the hip; specifically, there was a transition from evenly distributed loading along the acetabular articular surface to loading concentrated mainly in the superior portion of the articular surface during simulated single leg stance. However, the majority of posterior wall fractures involve a smaller amount of the articular surface. Posterior wall acetabular fractures not associated with instability of the hip are commonly treated nonoperatively. This practice does not account for the size of the posterior wall fracture. To study the biomechanical consequences of variably sized articular defects, a laboratory experiment was conducted evaluating three progressively larger posterior wall defects of the acetabulum during simulated single leg stance using superlow Fuji prescale film (Itochu International, New York): (a) 1/3 articular surface width through a 50 degrees arc along the posterior wall of the acetabulum, (b) 2/3, and (c) 3/3 articular width defects through the same 50 degrees arc along the posterior wall of the acetabulum. In the intact acetabulum, 48% of the total articular contact was located in the superior acetabulum. Twenty-eight percent of articular contact was in the anterior wall region of the acetabulum and 24% in the posterior wall region. After the 1/3 width posterior wall defect, 64% of the articular contact was located in the superior acetabulum (p = 0.0011). The 2/3 width posterior wall defect resulted in 71% of articular contact area being located in the superior acetabulum (p = 0.0006). After the 3/3 width posterior wall defect, 77% of articular contact was located in the superior acetabulum, significantly greater than the intact condition (p < 0

A method for detecting fungal contaminants in wall cavities.

PubMed

Spurgeon, Joe C

2003-01-01

This article describes a practical method for detecting the presence of both fungal spores and culturable fungi in wall cavities. Culturable fungi were collected in 25 mm cassettes containing 0.8 microm mixed cellulose ester filters using aggressive sampling conditions. Both culturable fungi and fungal spores were collected in modified slotted-disk cassettes. The sample volume was 4 L. The filters were examined microscopically and dilution plated onto multiple culture media. Collecting airborne samples in filter cassettes was an effective method for assessing wall cavities for fungal contaminants, especially because this method allowed the sample to be analyzed by both microscopy and culture media. Assessment criteria were developed that allowed the sample results to be used to classify wall cavities as either uncontaminated or contaminated. As a criterion, wall cavities with concentrations of culturable fungi below the limit of detection (LOD) were classified as uncontaminated, whereas those cavities with detectable concentrations of culturable fungi were classified as contaminated. A total of 150 wall cavities was sampled as part of a field project. The concentrations of culturable fungi were below the LOD in 34% of the samples, whereas Aspergillus and/or Penicillium were the only fungal genera detected in 69% of the samples in which culturable fungi were detected. Spore counting resulted in the detection of Stachybotrys-like spores in 25% of the samples that were analyzed, whereas Stachybotrys chartarum colonies were only detected on 2% of malt extract agar plates and on 6% of corn meal agar plates.

Persistence and distribution of 4-nonylphenol in water, sediment, macrophytes, and wall material of littoral enclosures

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

Heinis, L.J.; Tunell, R.; Liber, K.

1994-12-31

Eighteen enclosures (5 m x 10 m) were constructed in the littoral zone of a 2-ha pond near Duluth, MN. Each enclosure consisted of 5 m of natural shoreline and three walls of an inert plastic. The enclosures had an average surface area of 31.9 m{sup 2} , an average depth of 0.6 m and an average water volume of 33.1 m{sup 3}. The enclosure waters were treated with the alkyl phenol ethoxylate precursor and degradation product 4-nonylphenol. Application was accomplished by sub-surface injection over a 20-day period with a 2 day frequency. Nominal aqueous concentrations were 0, 3, 30,more » 100 and 300 {mu}g/L. Concentrations of 4-nonylphenol were monitored during and after application in the water, sediment, macrophytes, and enclosure wall material. Average maximum water concentrations ranged from 96.5% of nominal to 62.0% of nominal and average minimum water concentrations ranged from 33.3% of nominal to 29.5% of nominal during the application period. Water concentrations decreased exponentially after application ended. Sediment concentrations during the application period were constant from 8 to 20 d and peak concentrations occurred 48 d after application began. Macrophyte concentrations peaked 21 d after initial application with a steady decline through 76 d. Enclosure wall material concentrations reached a peak 3 h before the final application. A gradual decline occurred until 34 d after initial application followed by a more rapid dissipation.« less

Methods for quantitative measurement of tooth wear using the area and volume of virtual model cusps.

PubMed

Kim, Soo-Hyun; Park, Young-Seok; Kim, Min-Kyoung; Kim, Sulhee; Lee, Seung-Pyo

2018-04-01

Clinicians must examine tooth wear to make a proper diagnosis. However, qualitative methods of measuring tooth wear have many disadvantages. Therefore, this study aimed to develop and evaluate quantitative parameters using the cusp area and volume of virtual dental models. The subjects of this study were the same virtual models that were used in our former study. The same age group classification and new tooth wear index (NTWI) scoring system were also reused. A virtual occlusal plane was generated with the highest cusp points and lowered vertically from 0.2 to 0.8 mm to create offset planes. The area and volume of each cusp was then measured and added together. In addition to the former analysis, the differential features of each cusp were analyzed. The scores of the new parameters differentiated the age and NTWI groups better than those analyzed in the former study. The Spearman ρ coefficients between the total area and the area of each cusp also showed higher scores at the levels of 0.6 mm (0.6A) and 0.8A. The mesiolingual cusp (MLC) showed a statistically significant difference ( P <0.01) from the other cusps in the paired t -test. Additionally, the MLC exhibited the highest percentage of change at 0.6A in some age and NTWI groups. Regarding the age groups, the MLC showed the highest score in groups 1 and 2. For the NTWI groups, the MLC was not significantly different in groups 3 and 4. These results support the proposal that the lingual cusp exhibits rapid wear because it serves as a functional cusp. Although this study has limitations due to its cross-sectional nature, it suggests better quantitative parameters and analytical tools for the characteristics of cusp wear.

Methods for quantitative measurement of tooth wear using the area and volume of virtual model cusps

PubMed Central

2018-01-01

Purpose Clinicians must examine tooth wear to make a proper diagnosis. However, qualitative methods of measuring tooth wear have many disadvantages. Therefore, this study aimed to develop and evaluate quantitative parameters using the cusp area and volume of virtual dental models. Methods The subjects of this study were the same virtual models that were used in our former study. The same age group classification and new tooth wear index (NTWI) scoring system were also reused. A virtual occlusal plane was generated with the highest cusp points and lowered vertically from 0.2 to 0.8 mm to create offset planes. The area and volume of each cusp was then measured and added together. In addition to the former analysis, the differential features of each cusp were analyzed. Results The scores of the new parameters differentiated the age and NTWI groups better than those analyzed in the former study. The Spearman ρ coefficients between the total area and the area of each cusp also showed higher scores at the levels of 0.6 mm (0.6A) and 0.8A. The mesiolingual cusp (MLC) showed a statistically significant difference (P<0.01) from the other cusps in the paired t-test. Additionally, the MLC exhibited the highest percentage of change at 0.6A in some age and NTWI groups. Regarding the age groups, the MLC showed the highest score in groups 1 and 2. For the NTWI groups, the MLC was not significantly different in groups 3 and 4. These results support the proposal that the lingual cusp exhibits rapid wear because it serves as a functional cusp. Conclusions Although this study has limitations due to its cross-sectional nature, it suggests better quantitative parameters and analytical tools for the characteristics of cusp wear. PMID:29770241

Investigation of the effect of tablet surface area/volume on drug release from hydroxypropylmethylcellulose controlled-release matrix tablets.

PubMed

Reynolds, Thomas D; Mitchell, Shawn A; Balwinski, Karen M

2002-04-01

The purpose of this study was to investigate the influence of tablet surface area/volume (SA/Vol) on drug release from controlled-release matrix tablets containing hydroxypropylmethylcellulose (HPMC). Soluble drugs (promethazine HCl, diphenhydramine HCl, and propranolol HCl) were utilized in this study to give predominantly diffusion-controlled release. Drug release from HPMC matrix tablets with similar values of SA/Vol was comparable within the same tablet shape (i.e., flat-faced round tablets) and among different shapes (i.e., oval, round concave, flat-faced beveled-edge, and flat-faced round tablets). Tablets having the same surface area but different SA/Vol values did not result in similar drug release; tablets with larger SA/Vol values hadfaster release profiles. Utility of SA/Vol to affect drug release was demonstrated by changing drug doses, and altering tablet shape to adjust SA/Vol. When SA/Vol was held constant, similar release profiles were obtained with f2 metric values greater than 70. Thus, surface area/volume is one of the key variables in controlling drug release from HPMC matrix tablets. Proper use of this variable has practical application by formulators who may need to duplicate drug release profiles from tablets of different sizes and different shapes.

Chronic corticosterone affects brain weight, and mitochondrial, but not glial volume fraction in hippocampal area CA3.

PubMed

Coburn-Litvak, P S; Tata, D A; Gorby, H E; McCloskey, D P; Richardson, G; Anderson, B J

2004-01-01

Corticosterone (CORT), the predominant glucocorticoid in rodents, is known to damage hippocampal area CA3. Here we investigate how that damage is represented at the cellular and ultrastructural level of analyses. Rats were injected with CORT (26.8 mg/kg, s.c.) or vehicle for 56 days. Cell counts were estimated with the physical disector method. Glial and mitochondrial volume fractions were obtained from electron micrographs. The effectiveness of the CORT dose used was demonstrated in two ways. First, CORT significantly inhibited body weight gain relative to vehicles. Second, CORT significantly reduced adrenal gland, heart and gastrocnemius muscle weight. Both the adrenal and gastrocnemius muscle weight to body weight ratios were also significantly reduced. Although absolute brain weight was reduced, the brain to body weight ratio was higher in the CORT group relative to vehicles, suggesting that the brain is more resistant to the effects of CORT than many peripheral organs and muscles. Consistent with that interpretation, CORT did not alter CA3 cell density, cell layer volume, or apical dendritic neuropil volume. Likewise, CORT did not significantly alter glial volume fraction, but did reduce mitochondrial volume fraction. These findings highlight the need for ultrastructural analyses in addition to cellular level analyses before conclusions can be drawn about the damaging effects of prolonged CORT elevations. The relative reduction in mitochondria may indicate a reduction in bioenergetic capacity that, in turn, could render CA3 vulnerable to metabolic challenges.

Wall shear stress measurement in blade end-wall corner region

NASA Technical Reports Server (NTRS)

Bhargava, R.; Raj, R.; Boldman, D. R.

1987-01-01

The magnitude and the direction of wall shear stress and surface pressure in the blade end-wall corner region were investigated. The measurements were obtained on a specially designed Preston tube, the tip of which could be concentrically rotated about its axis of rotation at the measurement location. The magnitude of wall shear stress in the vicinity of the corner was observed to increase significantly (170 percent) compared to its far-upstream value; the increase was consistently higher on the blade surface compared to the value on the plate surface of the blade end-wall corner. On both surfaces in the blade end-wall corner, the variation of the wall shear stress direction was found to be more predominant in the vicinity of the blade leading-edge location. The trend of the measured wall shear stress direction showed good agreement with the limiting streamline directions obtained from the flow visualization studies.

Simulated impacts of artificial groundwater recharge and discharge of the source area and source volume of an Atlantic Coastal Plain Stream, Delaware, USA

USGS Publications Warehouse

Kasper, Joshua W.; Denver, Judish M.; McKenna, Thomas E.; Ullman, William J.

2010-01-01

A numerical groundwater-flow model was used to characterize the source area and volume of Phillips Branch, a baseflow-dominated stream incising a highly permeable unconfined aquifer on the low relief Delmarva Peninsula, USA. Particle-tracking analyses indicate that the source area (5.51 km2) is ~20% smaller than the topographically defined watershed (6.85 km2), and recharge entering ~37% of the surface watershed does not discharge to Phillips Branch. Groundwater residence time within the source volume ranges from a few days to almost 100 years, with 95% of the volume "flushing" within 50 years. Artificial discharge from groundwater pumping alters the shape of the source area and reduces baseflow due to the interception of stream flow paths, but has limited impacts on the residence time of groundwater discharged as baseflow. In contrast, artificial recharge from land-based wastewater disposal substantially reduces the source area, lowers the range in residence time due to the elimination of older flow paths to the stream, and leads to increased discharge to adjacent surface-water bodies. This research suggests that, in this and similar hydrogeologic settings, the "watershed" approach to water-resource management may be limited, particularly where anthropogenic stresses alter the transport of soluble contaminants through highly permeable unconfined aquifers.

Cell wall elasticity: I. A critique of the bulk elastic modulus approach and an analysis using polymer elastic principles

NASA Technical Reports Server (NTRS)

Wu, H. I.; Spence, R. D.; Sharpe, P. J.; Goeschl, J. D.

1985-01-01

The traditional bulk elastic modulus approach to plant cell pressure-volume relations is inconsistent with its definition. The relationship between the bulk modulus and Young's modulus that forms the basis of their usual application to cell pressure-volume properties is demonstrated to be physically meaningless. The bulk modulus describes stress/strain relations of solid, homogeneous bodies undergoing small deformations, whereas the plant cell is best described as a thin-shelled, fluid-filled structure with a polymer base. Because cell walls possess a polymer structure, an alternative method of mechanical analysis is presented using polymer elasticity principles. This initial study presents the groundwork of polymer mechanics as would be applied to cell walls and discusses how the matrix and microfibrillar network induce nonlinear stress/strain relationships in the cell wall in response to turgor pressure. In subsequent studies, these concepts will be expanded to include anisotropic expansion as regulated by the microfibrillar network.

Wall-based identification of coherent structures in wall-bounded turbulence

NASA Astrophysics Data System (ADS)

Sanmiguel Vila, C.; Flores, O.

2018-04-01

During the last decades, a number of reduced order models based on coherent structures have been proposed to describe wall-bounded turbulence. Many of these models emphasize the importance of coherent wall-normal velocity eddies (ν-eddies), which drive the generation of the very long streamwise velocity structures observed in the logarithmic and outer region. In order to use these models to improve our ability to control wall-bounded turbulence in realistic applications, these ν-eddies need to be identified from the wall in a non-intrusive way. In this paper, the possibility of using the pressure signal at the wall to identify these ν-eddies is explored, analyzing the cross-correlation between the wall-normal velocity component and the pressure fluctuations at the wall in a DNS of a turbulent channel flow at Reτ = 939. The results show that the cross-correlation has a region of negative correlation upstream, and a region of positive correlation backwards. In the spanwise direction the correlation decays monotonously, except very close to the wall where a change of sign of the correlation coefficient is observed. Moreover, filtering the pressure fluctuations at the wall in space results in an increase of the region where the cross-correlation is strong, both for the positively and the negatively correlated regions. The use of a time filter for the pressure fluctuations at the wall yields different results, displacing the regions of strong correlation without changing much their sizes. The results suggest that space-filtering the pressure at the wall is a feasible way to identify ν-eddies of different sizes, which could be used to trigger turbulent control strategies.

Spontaneous Behaviors and Wall-Curvature Lead to Apparent Wall Preference in Planarian

PubMed Central

Akiyama, Yoshitaro; Agata, Kiyokazu; Inoue, Takeshi

2015-01-01

The planarian Dugesia japonica tends to stay near the walls of its breeding containers and experimental dishes in the laboratory, a phenomenon called “wall preference”. This behavior is thought to be important for environmental adaptation, such as hiding by planarians in nature. However, the mechanisms regulating wall-preference behavior are not well understood, since this behavior occurs in the absence of any particular stimulation. Here we show the mechanisms of wall-preference behavior. Surprisingly, planarian wall-preference behavior was also shown even by the head alone and by headless planarians. These results indicate that planarian “wall-preference” behavior only appears to be a “preference” behavior, and is actually an outcome of spontaneous behaviors, rather than of brain function. We found that in the absence of environmental cues planarians moved basically straight ahead until they reached a wall, and that after reaching a wall, they changed their direction of movement to one tangential to the wall, suggesting that this spontaneous behavior may play a critical role in the wall preference. When we tested another spontaneous behavior, the wigwag movement of the planarian head, using computer simulation with various wigwag angles and wigwag intervals, large wigwag angle and short wigwag interval reduced wall-preference behavior. This indicated that wigwag movement may determine the probability of staying near the wall or leaving the wall. Furthermore, in accord with this simulation, when we tested planarian wall-preference behavior using several assay fields with different curvature of the wall, we found that concavity and sharp curvature of walls negatively impacted wall preference by affecting the permissible angle of the wigwag movement. Together, these results indicate that planarian wall preference may be involuntarily caused by the combination of two spontaneous planarian behaviors: moving straight ahead until reaching a wall and then

Dry granular avalanche impact force on a rigid wall: Analytic shock solution versus discrete element simulations

NASA Astrophysics Data System (ADS)

Albaba, Adel; Lambert, Stéphane; Faug, Thierry

2018-05-01

The present paper investigates the mean impact force exerted by a granular mass flowing down an incline and impacting a rigid wall of semi-infinite height. First, this granular flow-wall interaction problem is modeled by numerical simulations based on the discrete element method (DEM). These DEM simulations allow computing the depth-averaged quantities—thickness, velocity, and density—of the incoming flow and the resulting mean force on the rigid wall. Second, that problem is described by a simple analytic solution based on a depth-averaged approach for a traveling compressible shock wave, whose volume is assumed to shrink into a singular surface, and which coexists with a dead zone. It is shown that the dead-zone dynamics and the mean force on the wall computed from DEM can be reproduced reasonably well by the analytic solution proposed over a wide range of slope angle of the incline. These results are obtained by feeding the analytic solution with the thickness, the depth-averaged velocity, and the density averaged over a certain distance along the incline rather than flow quantities taken at a singular section before the jump, thus showing that the assumption of a shock wave volume shrinking into a singular surface is questionable. The finite length of the traveling wave upstream of the grains piling against the wall must be considered. The sensitivity of the model prediction to that sampling length remains complicated, however, which highlights the need of further investigation about the properties and the internal structure of the propagating granular wave.

Domain wall nanoelectronics

NASA Astrophysics Data System (ADS)

Catalan, G.; Seidel, J.; Ramesh, R.; Scott, J. F.

2012-01-01

Domains in ferroelectrics were considered to be well understood by the middle of the last century: They were generally rectilinear, and their walls were Ising-like. Their simplicity stood in stark contrast to the more complex Bloch walls or Néel walls in magnets. Only within the past decade and with the introduction of atomic-resolution studies via transmission electron microscopy, electron holography, and atomic force microscopy with polarization sensitivity has their real complexity been revealed. Additional phenomena appear in recent studies, especially of magnetoelectric materials, where functional properties inside domain walls are being directly measured. In this paper these studies are reviewed, focusing attention on ferroelectrics and multiferroics but making comparisons where possible with magnetic domains and domain walls. An important part of this review will concern device applications, with the spotlight on a new paradigm of ferroic devices where the domain walls, rather than the domains, are the active element. Here magnetic wall microelectronics is already in full swing, owing largely to the work of Cowburn and of Parkin and their colleagues. These devices exploit the high domain wall mobilities in magnets and their resulting high velocities, which can be supersonic, as shown by Kreines’ and co-workers 30 years ago. By comparison, nanoelectronic devices employing ferroelectric domain walls often have slower domain wall speeds, but may exploit their smaller size as well as their different functional properties. These include domain wall conductivity (metallic or even superconducting in bulk insulating or semiconducting oxides) and the fact that domain walls can be ferromagnetic while the surrounding domains are not.

Turbine airfoil with controlled area cooling arrangement

DOEpatents

Liang, George

2010-04-27

A gas turbine airfoil (10) includes a serpentine cooling path (32) with a plurality of channels (34,42,44) fluidly interconnected by a plurality of turns (38,40) for cooling the airfoil wall material. A splitter component (50) is positioned within at least one of the channels to bifurcate the channel into a pressure-side channel (46) passing in between the outer wall (28) and the inner wall (30) of the pressure side (24) and a suction-side channel (48) passing in between the outer wall (28) and the inner wall (30) of the suction side (26) longitudinally downstream of an intermediate height (52). The cross-sectional area of the pressure-side channel (46) and suction-side channel (48) are thereby controlled in spite of an increasing cross-sectional area of the airfoil along its longitudinal length, ensuring a sufficiently high mach number to provide a desired degree of cooling throughout the entire length of the airfoil.

19. INTERIOR OF UTILITY ROOM SHOWING STUCCO WALL/DRYWALL WALL TRANSITION, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. INTERIOR OF UTILITY ROOM SHOWING STUCCO WALL/DRYWALL WALL TRANSITION, ELECTRICAL JUNCTION BOXES, BUILT-IN WALL CABINETRY, AND ELECTRICAL WALL HEATER. VIEW TO NORTHEAST. - Bishop Creek Hydroelectric System, Plant 4, Worker Cottage, Bishop Creek, Bishop, Inyo County, CA

Cell wall microstructure, pore size distribution and absolute density of hemp shiv

NASA Astrophysics Data System (ADS)

Jiang, Y.; Lawrence, M.; Ansell, M. P.; Hussain, A.

2018-04-01

This paper, for the first time, fully characterizes the intrinsic physical parameters of hemp shiv including cell wall microstructure, pore size distribution and absolute density. Scanning electron microscopy revealed microstructural features similar to hardwoods. Confocal microscopy revealed three major layers in the cell wall: middle lamella, primary cell wall and secondary cell wall. Computed tomography improved the visualization of pore shape and pore connectivity in three dimensions. Mercury intrusion porosimetry (MIP) showed that the average accessible porosity was 76.67 ± 2.03% and pore size classes could be distinguished into micropores (3-10 nm) and macropores (0.1-1 µm and 20-80 µm). The absolute density was evaluated by helium pycnometry, MIP and Archimedes' methods. The results show that these methods can lead to misinterpretation of absolute density. The MIP method showed a realistic absolute density (1.45 g cm-3) consistent with the density of the known constituents, including lignin, cellulose and hemi-cellulose. However, helium pycnometry and Archimedes' methods gave falsely low values owing to 10% of the volume being inaccessible pores, which require sample pretreatment in order to be filled by liquid or gas. This indicates that the determination of the cell wall density is strongly dependent on sample geometry and preparation.

WallGen, software to construct layered cellulose-hemicellulose networks and predict their small deformation mechanics.

PubMed

Kha, Hung; Tuble, Sigrid C; Kalyanasundaram, Shankar; Williamson, Richard E

2010-02-01

We understand few details about how the arrangement and interactions of cell wall polymers produce the mechanical properties of primary cell walls. Consequently, we cannot quantitatively assess if proposed wall structures are mechanically reasonable or assess the effectiveness of proposed mechanisms to change mechanical properties. As a step to remedying this, we developed WallGen, a Fortran program (available on request) building virtual cellulose-hemicellulose networks by stochastic self-assembly whose mechanical properties can be predicted by finite element analysis. The thousands of mechanical elements in the virtual wall are intended to have one-to-one spatial and mechanical correspondence with their real wall counterparts of cellulose microfibrils and hemicellulose chains. User-defined inputs set the properties of the two polymer types (elastic moduli, dimensions of microfibrils and hemicellulose chains, hemicellulose molecular weight) and their population properties (microfibril alignment and volume fraction, polymer weight percentages in the network). This allows exploration of the mechanical consequences of variations in nanostructure that might occur in vivo and provides estimates of how uncertainties regarding certain inputs will affect WallGen's mechanical predictions. We summarize WallGen's operation and the choice of values for user-defined inputs and show that predicted values for the elastic moduli of multinet walls subject to small displacements overlap measured values. "Design of experiment" methods provide systematic exploration of how changed input values affect mechanical properties and suggest that changing microfibril orientation and/or the number of hemicellulose cross-bridges could change wall mechanical anisotropy.

BUILDING 122 CONTAINS THREE GENERAL AREAS: OFFICE AREAS, INTERNAL DOSIMETRY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

BUILDING 122 CONTAINS THREE GENERAL AREAS: OFFICE AREAS, INTERNAL DOSIMETRY, AND MEDICAL/HEALTH. BUILDING 122 SHARES A COMMON WALL WITH BUILDING 121, THE PLANT SECURITY BUILDING. THE TWO-STORY BUILDING IN THE BACKGROUND IS BUILDING 111. (9/26/52) - Rocky Flats Plant, Emergency Medical Services Facility, Southwest corner of Central & Third Avenues, Golden, Jefferson County, CO

22. SIDE WALL CONSTRUCTION, NORTH TRAINING WALL, LOOKING WEST FROM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. SIDE WALL CONSTRUCTION, NORTH TRAINING WALL, LOOKING WEST FROM THE SAME POINT AS VIEW NO. 21. - Oakland Harbor Training Walls, Mouth of Federal Channel to Inner Harbor, Oakland, Alameda County, CA

Isolated development of inner (wall) caries like lesions in a bacterial-based in vitro model.

PubMed

Diercke, K; Lussi, A; Kersten, T; Seemann, R

2009-12-01

The study conducted in a bacterial-based in vitro caries model aimed to determine whether typical inner secondary caries lesions can be detected at cavity walls of restorations with selected gap widths when the development of outer lesions is inhibited. Sixty bovine tooth specimens were randomly assigned to the following groups: test group 50 (TG50; gap, 50 microm), test group 100 (TG100; gap, 100 microm), test group 250 (TG250; gap, 250 microm) and a control group (CG; gap, 250 microm). The outer tooth surface of the test group specimens was covered with an acid-resistant varnish to inhibit the development of an outer caries lesion. After incubation in the caries model, the area of demineralization at the cavity wall was determined by confocal laser scanning microscopy. All test group specimens demonstrated only wall lesions. The CG specimens developed outer and wall lesions. The TG250 specimens showed significantly less wall lesion area compared to the CG (p < 0.05). In the test groups, a statistically significant increase (p < 0.05) in lesion area could be detected in enamel between TG50 and TG250 and in dentine between TG50 and TG100. In conclusion, the inner wall lesions of secondary caries can develop without the presence of outer lesions and therefore can be regarded as an entity on their own. The extent of independently developed wall lesions increased with gap width in the present setting.

Giant fibrosarcoma prostuberans of abodominal wall: management problems in resources-constrained country.

PubMed

Chukwuanukwu, T O G; Anyanwu, S N C

2009-09-01

Abdominal wall sarcomas represent less than 1% of adult malignancies. Dermatofibrosarcoma protuberans can grow to very large sizes and the recommended resection 2-3 cm from the macroscopic tumour margin can produce very large full thickness defects of the abdominal wall. Reconstruction of such defects can be quite challenging in resource constrained areas where patients present late with giant lesions. To highlight the presentation and management challenges faced by the surgical oncologist and reconstructive surgeon in a resource constrained country when faced with giant Dermatofibrosarcoma protuberans of the abdominal wall. Prospective study of patients with abdominal wall soft tissue sarcoma presenting to the authors. Cases of giant dermatofibrosarcoma protuberns who underwent surgery were analysed. Seven cases managed over an eight year period (January 2000 to December 2007). Age ranged from 27-70 yrs with slight female preponderance 1.5:1 F:M. Three presented with recurrent fungating masses. Only one could be reconstructed with prolene mesh. One recurrence was noted during the period under study. Poverty, ignorance and lack of necessary working tools are major challenges faced by the surgical oncologist and reconstructive surgeon in resource constrained areas and pose a major obstacle to the control of cancer in these areas.

Wall Shear Stress, Wall Pressure and Near Wall Velocity Field Relationships in a Whirling Annular Seal

NASA Technical Reports Server (NTRS)

Morrison, Gerald L.; Winslow, Robert B.; Thames, H. Davis, III

1996-01-01

The mean and phase averaged pressure and wall shear stress distributions were measured on the stator wall of a 50% eccentric annular seal which was whirling in a circular orbit at the same speed as the shaft rotation. The shear stresses were measured using flush mounted hot-film probes. Four different operating conditions were considered consisting of Reynolds numbers of 12,000 and 24,000 and Taylor numbers of 3,300 and 6,600. At each of the operating conditions the axial distribution (from Z/L = -0.2 to 1.2) of the mean pressure, shear stress magnitude, and shear stress direction on the stator wall were measured. Also measured were the phase averaged pressure and shear stress. These data were combined to calculate the force distributions along the seal length. Integration of the force distributions result in the net forces and moments generated by the pressure and shear stresses. The flow field inside the seal operating at a Reynolds number of 24,000 and a Taylor number of 6,600 has been measured using a 3-D laser Doppler anemometer system. Phase averaged wall pressure and wall shear stress are presented along with phase averaged mean velocity and turbulence kinetic energy distributions located 0.16c from the stator wall where c is the seal clearance. The relationships between the velocity, turbulence, wall pressure and wall shear stress are very complex and do not follow simple bulk flow predictions.

GeoWall Experiences in K-12 Education

NASA Astrophysics Data System (ADS)

Johnson, A. E.

2003-12-01

Since the mid 1990s the Electronic Visualization Laboratory at the University of Illinois at Chicago has been investigating how advanced visualization technology such as CAVEs, ImmersaDesks, PCs, and plasma panels can be used effectively in K-12 education. The creation of the GeoWall has given us more flexibility in deploying these technologies, and conducting these investigations outside the laboratory. Over the two years we have been using GeoWalls in a variety of educational settings around the Chicago area. Since the Fall of 2002, the SciTech Museum in Aurora, IL has used a GeoWall to show a variety of educational content. In February 2002 the Museum of Science and Industry in Chicago, IL set up a GeoWall to show 'Virtual Harlem' which allowed museum patrons to walk the streets of Harlem NY in the 1930s to learn about the place and the people. Since 1999 we have been working with Abraham Lincoln Elementary School in Oak Park, IL using a variety of display devices to teach the scientific method and investigate the use of multiple perspectives in learning. We began using a GeoWall there in the spring of 2002 and in the spring of 2003 we expanded our work in Oak Park to include Gwendolyn Brooks Middle School.

Free-breathing black-blood CINE fast-spin echo imaging for measuring abdominal aortic wall distensibility: a feasibility study

NASA Astrophysics Data System (ADS)

Lin, Jyh-Miin; Patterson, Andrew J.; Chao, Tzu-Cheng; Zhu, Chengcheng; Chang, Hing-Chiu; Mendes, Jason; Chung, Hsiao-Wen; Gillard, Jonathan H.; Graves, Martin J.

2017-05-01

The paper reports a free-breathing black-blood CINE fast-spin echo (FSE) technique for measuring abdominal aortic wall motion. The free-breathing CINE FSE includes the following MR techniques: (1) variable-density sampling with fast iterative reconstruction; (2) inner-volume imaging; and (3) a blood-suppression preparation pulse. The proposed technique was evaluated in eight healthy subjects. The inner-volume imaging significantly reduced the intraluminal artifacts of respiratory motion (p  =  0.015). The quantitative measurements were a diameter of 16.3  ±  2.8 mm and wall distensibility of 2.0  ±  0.4 mm (12.5  ±  3.4%) and 0.7  ±  0.3 mm (4.1  ±  1.0%) for the anterior and posterior walls, respectively. The cyclic cross-sectional distensibility was 35  ±  15% greater in the systolic phase than in the diastolic phase. In conclusion, we developed a feasible CINE FSE method to measure the motion of the abdominal aortic wall, which will enable clinical scientists to study the elasticity of the abdominal aorta.

Silver plating technique seals leaks in thin wall tubing joints

NASA Technical Reports Server (NTRS)

Blenderman, W. H.

1966-01-01

Leaks in thin wall tubing joints are sealed by cleaning and silver plating the hot gas side of the joint in the leakage area. The pressure differential across the silver during hydrostatic test and subsequent use forces the ductile silver into the leak area and seals it.

Synthesis and CO{sub 2} adsorption study of modified MOF-5 with multi-wall carbon nanotubes and expandable graphite

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

Ullah, Sami, E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Bustam, M. A., E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com; Shariff, A. M., E-mail: samichemist1@gmail.com, E-mail: azmibustam@petronas.com.my, E-mail: azmish@petronas.com.my, E-mail: lkhlfh@gmail.com, E-mail: hmurshid@gmail.com, E-mail: nadiariazz@gmail.com

2014-10-24

MOF-5 was synthesized by solvothermal method and its reactivation under anhydrous conditions. This research is conducted to investigate the effect of MOF-5 and MOF-5 modified with multi-wall carbon nanotubes (MWCNTs) and expandable graphite (EG) on the performance of CO{sub 2} adsorption. The synthesized MOFs were characterized using Field emission scanning electron microscopy (FESEM) for surface morphology, Thermogravimetric analysis (TGA) for thermal stability, X-ray diffraction (XRD) for crystals plane, Brunauer-Emmet-Teller (BET) for surface area and CO{sub 2} adsorption. The result had showed that the modified MOF-5 enhanced the CO{sub 2} adsorption compared to the pure MOF-5. The increment in the CO{submore » 2} uptake capacities of MOF materials was attributed to the decrease in the pore size and enhancement of micropore volume of MOF-5 by multi-walled carbon nanotube and EG incorporation. The BET surface area of the synthesized MOF-5@MWCNTs is more than MOF-5. The CO{sub 2} sorption capacities of MOF-5 and MOF-5@MWCNTs were observed to increase from 0.00008 to 0.00048 mol g-1 at 298 K and 1 bar. The modified MOF-5@MWCNTs resulted in the highest CO{sub 2} adsorption followed by the modified MOF-5@ EG and lastly, MOF-5.« less

Direct Measurement of Proximal Isovelocity Surface Area by Real-Time Three-Dimensional Color Doppler for Quantitation of Aortic Regurgitant Volume: An In Vitro Validation

PubMed Central

Pirat, Bahar; Little, Stephen H.; Igo, Stephen R.; McCulloch, Marti; Nosé, Yukihiko; Hartley, Craig J.; Zoghbi, William A.

2012-01-01

Objective The proximal isovelocity surface area (PISA) method is useful in the quantitation of aortic regurgitation (AR). We hypothesized that actual measurement of PISA provided with real-time 3-dimensional (3D) color Doppler yields more accurate regurgitant volumes than those estimated by 2-dimensional (2D) color Doppler PISA. Methods We developed a pulsatile flow model for AR with an imaging chamber in which interchangeable regurgitant orifices with defined shapes and areas were incorporated. An ultrasonic flow meter was used to calculate the reference regurgitant volumes. A total of 29 different flow conditions for 5 orifices with different shapes were tested at a rate of 72 beats/min. 2D PISA was calculated as 2π r2, and 3D PISA was measured from 8 equidistant radial planes of the 3D PISA. Regurgitant volume was derived as PISA × aliasing velocity × time velocity integral of AR/peak AR velocity. Results Regurgitant volumes by flow meter ranged between 12.6 and 30.6 mL/beat (mean 21.4 ± 5.5 mL/beat). Regurgitant volumes estimated by 2D PISA correlated well with volumes measured by flow meter (r = 0.69); however, a significant underestimation was observed (y = 0.5x + 0.6). Correlation with flow meter volumes was stronger for 3D PISA-derived regurgitant volumes (r = 0.83); significantly less underestimation of regurgitant volumes was seen, with a regression line close to identity (y = 0.9x + 3.9). Conclusion Direct measurement of PISA is feasible, without geometric assumptions, using real-time 3D color Doppler. Calculation of aortic regurgitant volumes with 3D color Doppler using this methodology is more accurate than conventional 2D method with hemispheric PISA assumption. PMID:19168322

Direct measurement of proximal isovelocity surface area by real-time three-dimensional color Doppler for quantitation of aortic regurgitant volume: an in vitro validation.

PubMed

Pirat, Bahar; Little, Stephen H; Igo, Stephen R; McCulloch, Marti; Nosé, Yukihiko; Hartley, Craig J; Zoghbi, William A

2009-03-01

The proximal isovelocity surface area (PISA) method is useful in the quantitation of aortic regurgitation (AR). We hypothesized that actual measurement of PISA provided with real-time 3-dimensional (3D) color Doppler yields more accurate regurgitant volumes than those estimated by 2-dimensional (2D) color Doppler PISA. We developed a pulsatile flow model for AR with an imaging chamber in which interchangeable regurgitant orifices with defined shapes and areas were incorporated. An ultrasonic flow meter was used to calculate the reference regurgitant volumes. A total of 29 different flow conditions for 5 orifices with different shapes were tested at a rate of 72 beats/min. 2D PISA was calculated as 2pi r(2), and 3D PISA was measured from 8 equidistant radial planes of the 3D PISA. Regurgitant volume was derived as PISA x aliasing velocity x time velocity integral of AR/peak AR velocity. Regurgitant volumes by flow meter ranged between 12.6 and 30.6 mL/beat (mean 21.4 +/- 5.5 mL/beat). Regurgitant volumes estimated by 2D PISA correlated well with volumes measured by flow meter (r = 0.69); however, a significant underestimation was observed (y = 0.5x + 0.6). Correlation with flow meter volumes was stronger for 3D PISA-derived regurgitant volumes (r = 0.83); significantly less underestimation of regurgitant volumes was seen, with a regression line close to identity (y = 0.9x + 3.9). Direct measurement of PISA is feasible, without geometric assumptions, using real-time 3D color Doppler. Calculation of aortic regurgitant volumes with 3D color Doppler using this methodology is more accurate than conventional 2D method with hemispheric PISA assumption.

Algorithm of chest wall keloid treatment

PubMed Central

Long, Xiao; Zhang, Mingzi; Wang, Yang; Zhao, Ru; Wang, Youbin; Wang, Xiaojun

2016-01-01

Abstract Keloids are common in the Asian population. Multiple or huge keloids can appear on the chest wall because of its tendency to develop acne, sebaceous cyst, etc. It is difficult to find an ideal treatment for keloids in this area due to the limit of local soft tissues and higher recurrence rate. This study aims at establishing an individualized protocol that could be easily applied according to the size and number of chest wall keloids. A total of 445 patients received various methods (4 protocols) of treatment in our department from September 2006 to September 2012 according to the size and number of their chest wall keloids. All of the patients received adjuvant radiotherapy in our hospital. Patient and Observer Scar Assessment Scale (POSAS) was used to assess the treatment effect by both doctors and patients. With mean follow-up time of 13 months (range: 6–18 months), 362 patients participated in the assessment of POSAS with doctors. Both the doctors and the patients themselves used POSAS to evaluate the treatment effect. The recurrence rate was 0.83%. There was an obvious significant difference (P < 0.001) between the before-surgery score and the after-surgery score from both doctors and patients, indicating that both doctors and patients were satisfied with the treatment effect. Our preliminary clinical result indicates that good clinical results could be achieved by choosing the proper method in this algorithm for Chinese patients with chest wall keloids. This algorithm could play a guiding role for surgeons when dealing with chest wall keloid treatment. PMID:27583896

5. Detail of bin wall, showing the thinner exterior wall ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. Detail of bin wall, showing the thinner exterior wall next to the inner wall with its alternating courses of channel tile and hollow tile. - Saint Anthony Elevator No. 3, 620 Malcom Avenue, Southeast, Minneapolis, Hennepin County, MN

Quantification of the relative contribution of the different right ventricular wall motion components to right ventricular ejection fraction: the ReVISION method.

PubMed

Lakatos, Bálint; Tősér, Zoltán; Tokodi, Márton; Doronina, Alexandra; Kosztin, Annamária; Muraru, Denisa; Badano, Luigi P; Kovács, Attila; Merkely, Béla

2017-03-27

Three major mechanisms contribute to right ventricular (RV) pump function: (i) shortening of the longitudinal axis with traction of the tricuspid annulus towards the apex; (ii) inward movement of the RV free wall; (iii) bulging of the interventricular septum into the RV and stretching the free wall over the septum. The relative contribution of the aforementioned mechanisms to RV pump function may change in different pathological conditions.Our aim was to develop a custom method to separately assess the extent of longitudinal, radial and anteroposterior displacement of the RV walls and to quantify their relative contribution to global RV ejection fraction using 3D data sets obtained by echocardiography.Accordingly, we decomposed the movement of the exported RV beutel wall in a vertex based manner. The volumes of the beutels accounting for the RV wall motion in only one direction (either longitudinal, radial, or anteroposterior) were calculated at each time frame using the signed tetrahedron method. Then, the relative contribution of the RV wall motion along the three different directions to global RV ejection fraction was calculated either as the ratio of the given direction's ejection fraction to global ejection fraction and as the frame-by-frame RV volume change (∆V/∆t) along the three motion directions.The ReVISION (Right VentrIcular Separate wall motIon quantificatiON) method may contribute to a better understanding of the pathophysiology of RV mechanical adaptations to different loading conditions and diseases.

The Volume of Earth's Lakes

NASA Astrophysics Data System (ADS)

Cael, B. B.

How much water do lakes on Earth hold? Global lake volume estimates are scarce, highly variable, and poorly documented. We develop a mechanistic null model for estimating global lake mean depth and volume based on a statistical topographic approach to Earth's surface. The volume-area scaling prediction is accurate and consistent within and across lake datasets spanning diverse regions. We applied these relationships to a global lake area census to estimate global lake volume and depth. The volume of Earth's lakes is 199,000 km3 (95% confidence interval 196,000-202,000 km3) . This volume is in the range of historical estimates (166,000-280,000 km3) , but the overall mean depth of 41.8 m (95% CI 41.2-42.4 m) is significantly lower than previous estimates (62 - 151 m). These results highlight and constrain the relative scarcity of lake waters in the hydrosphere and have implications for the role of lakes in global biogeochemical cycles. We also evaluate the size (area) distribution of lakes on Earth compared to expectations from percolation theory. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. 2388357.

Effects of increased left ventricular wall thickness on the myocardium in severe aortic stenosis with normal left ventricular ejection fraction: Two- and three-dimensional multilayer speckle tracking echocardiography.

PubMed

Cho, Eun Jeong; Park, Sung-Ji; Kim, Eun Kyoung; Lee, Ga Yeon; Chang, Sung-A; Choi, Jin-Oh; Lee, Sang-Chol; Park, Seung Woo

2017-04-01

The aim of this study was to determine the capability of real time three-dimensional echocardiography (RT3DE) and two-dimensional (2D) multilayer speckle tracking echocardiography (MSTE) for evaluation of early myocardial dysfunction triggered by increased left ventricular (LV) wall thickness in severe aortic stenosis (AS) with normal LV ejection fraction (EF≥55%). Conventional, RT3D STE and 2D MSTE were performed in 45 patients (mean 68.9±9.0 years) with severe AS (aortic valve area <1 cm 2 , aortic velocity Vmax >4 m/s or mean PG >40 mm Hg) and normal left ventricular ejection fraction (LVEF) without overt coronary artery disease and in 18 age-, sex-matched healthy controls. Global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were calculated using RT3DE and MSTE. The severe AS group had lower 3D GLS, GRS, GAS and 2D epicardium, and mid-wall and endocardium GLS compared to healthy controls. In MSTE analysis, 2D LS and CS values decreased from the endocardial layer toward the epicardial layer. Severe AS patients with increased LV wall thickness had lower 3D GLS and 2D epicardium, and mid-wall and endocardium GLS compared with severe AS patients without LV wall thickening. GLS on RT3D STE was correlated with GLS on 2D MSTE, left ventricular mass index, LVEF, left atrial volume index, and lnNT-proBNP. RT3DE and 2D MSTE can be used to identify subtle contractile dysfunction triggered by increased LV wall thickness in severe AS with normal LVEF. Therefore, RT3D STE and 2D MSTE may provide additional information that can facilitate decision-making regarding severe AS patients with increased LV wall thickness and normal LV function. © 2017, Wiley Periodicals, Inc.

Rough-Wall Channel Analysis Using Suboptimal Control Theory

NASA Technical Reports Server (NTRS)

Flores, O.; Jimenez, J.; Tenpleton, J.

2003-01-01

The original aim of this work was to shed some light on the physics of turbulence over rough walls using large-eddy simulations and the suboptimal-control wall boundary conditions introduced by Nicoud et al. It was hoped that, if that algorithm was used to fit the mean velocity profile of the simulations to that of a rough-walled channel, instead of to a smooth one, the wall stresses introduced by the control algorithm would give some indication of what aspects of rough walls are most responsible for the modification of the flow in real turbulence. It was similarly expected that the structure of the resulting velocity fluctuations would share some of the characteristics of rough-walled flows, thus again suggesting what is intrinsic and what is accidental in the effect of geometric wall roughness. A secondary goal was to study the effect of 'unphysical' boundary conditions on the outside flow by observing how a relatively major change of the target velocity profile, and therefore presumably of the applied wall stresses, modifies properties such as the dominant length scales of the velocity fluctuations away from the wall. As will be seen below, this secondary goal grew more important during the course of the study, which was carried out during a short summer visit of the first two authors to the CTR. It became clear that there are open questions about the way in which the control algorithm models the boundary conditions, even for smooth walls, and that these questions make the physical interpretation of the results difficult. Considerable more work in that area seems to be needed before even relatively advanced large-eddy simulations, such as these, can be used to draw conclusions about the physics of wall-bounded turbulent flows. The numerical method is the same as in Nicoud et al. The modifications introduced in the original code are briefly described in section 2, but the original paper should be consulted for a full description of the algorithm. The results are

Digital Fresnel reflection holography for high-resolution 3D near-wall flow measurement.

PubMed

Kumar, S Santosh; Hong, Jiarong

2018-05-14

We propose a novel backscatter holographic imaging system, as a compact and effective tool for 3D near-wall flow diagnostics at high resolutions, utilizing light reflected at the solid-liquid interface as a reference beam. The technique is fully calibrated, and is demonstrated in a densely seeded channel to achieve a spatial resolution of near-wall flows equivalent to or exceeding prior digital inline holographic measurements using local tracer seeding technique. Additionally, we examined the effects of seeding concentration and laser coherence on the measurement resolution and sample volume resolved, demonstrating the potential to manipulate sample domain by tuning the laser coherence profile.

Chest wall mechanics in sustained microgravity

NASA Technical Reports Server (NTRS)

Wantier, M.; Estenne, M.; Verbanck, S.; Prisk, G. K.; Paiva, M.; West, J. B. (Principal Investigator)

1998-01-01

We assessed the effects of sustained weightlessness on chest wall mechanics in five astronauts who were studied before, during, and after the 10-day Spacelab D-2 mission (n = 3) and the 180-day Euromir-95 mission (n = 2). We measured flow and pressure at the mouth and rib cage and abdominal volumes during resting breathing and during a relaxation maneuver from midinspiratory capacity to functional residual capacity. Microgravity produced marked and consistent changes (Delta) in the contribution of the abdomen to tidal volume [DeltaVab/(DeltaVab + DeltaVrc), where Vab is abdominal volume and Vrc is rib cage volume], which increased from 30.7 +/- 3. 5 (SE)% at 1 G head-to-foot acceleration to 58.3 +/- 5.7% at 0 G head-to-foot acceleration (P < 0.005). Values of DeltaVab/(DeltaVab + DeltaVrc) did not change significantly during the 180 days of the Euromir mission, but in the two subjects DeltaVab/(DeltaVab + DeltaVrc) was greater on postflight day 1 than on subsequent postflight days or preflight. In the two subjects who produced satisfactory relaxation maneuvers, the slope of the Konno-Mead plot decreased in microgravity; this decrease was entirely accounted for by an increase in abdominal compliance because rib cage compliance did not change. These alterations are similar to those previously reported during short periods of weightlessness inside aircrafts flying parabolic trajectories. They are also qualitatively similar to those observed on going from upright to supine posture; however, in contrast to microgravity, such postural change reduces rib cage compliance.

Nanoparticles for cultural heritage conservation: calcium and barium hydroxide nanoparticles for wall painting consolidation.

PubMed

Giorgi, Rodorico; Ambrosi, Moira; Toccafondi, Nicola; Baglioni, Piero

2010-08-16

Nanotechnology provides new concepts and materials for the consolidation and protection of wall paintings. In particular, humble calcium and barium hydroxide nanoparticles offer a versatile and highly efficient tool to combat the main degradation processes altering wall paintings. Clear example of the efficacy and potentiality of nanotechnology is represented by the conservation in situ of Maya wall paintings in the archaeological area in Calakmul (Mexico).

POROUS WALL, HOLLOW GLASS MICROSPHERES

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

Sexton, W.

Hollow Glass Microspheres (HGM) is not a new technology. All one has to do is go to the internet and Google{trademark} HGM. Anyone can buy HGM and they have a wide variety of uses. HGM are usually between 1 to 100 microns in diameter, although their size can range from 100 nanometers to 5 millimeters in diameter. HGM are used as lightweight filler in composite materials such as syntactic foam and lightweight concrete. In 1968 a patent was issued to W. Beck of the 3M{trademark} Company for 'Glass Bubbles Prepared by Reheating Solid Glass Particles'. In 1983 P. Howell wasmore » issued a patent for 'Glass Bubbles of Increased Collapse Strength' and in 1988 H. Marshall was issued a patent for 'Glass Microbubbles'. Now Google{trademark}, Porous Wall, Hollow Glass Microspheres (PW-HGMs), the key words here are Porous Wall. Almost every article has its beginning with the research done at the Savannah River National Laboratory (SRNL). The Savannah River Site (SRS) where SRNL is located has a long and successful history of working with hydrogen and its isotopes for national security, energy, waste management and environmental remediation applications. This includes more than 30 years of experience developing, processing, and implementing special ceramics, including glasses for a variety of Department of Energy (DOE) missions. In the case of glasses, SRS and SRNL have been involved in both the science and engineering of vitreous or glass based systems. As a part of this glass experience and expertise, SRNL has developed a number of niches in the glass arena, one of which is the development of porous glass systems for a variety of applications. These porous glass systems include sol gel glasses, which include both xerogels and aerogels, as well as phase separated glass compositions, that can be subsequently treated to produce another unique type of porosity within the glass forms. The porous glasses can increase the surface area compared to 'normal glasses of a 1 to 2 order

Development of an Interactive Shoreline Management Tool for the Lower Wood River Valley, Oregon - Phase I: Stage-Volume and Stage-Area Relations

USGS Publications Warehouse

Haluska, Tana L.; Snyder, Daniel T.

2007-01-01

This report presents the parcel and inundation area geographic information system (GIS) layers for various surface-water stages. It also presents data tables containing the water stage, inundation area, and water volume relations developed from analysis of detailed land surface elevation derived from Light Detection and Ranging (LiDAR) data recently collected for the Wood River Valley at the northern margin of Agency Lake in Klamath County, Oregon. Former shoreline wetlands that have been cut off from Upper Klamath and Agency Lakes by dikes might in the future be reconnected to Upper Klamath and Agency Lakes by breaching the dikes. Issues of interest associated with restoring wetlands in this way include the area that will be inundated, the volume of water that may be stored, the change in wetland habitat, and the variation in these characteristics as surface-water stage is changed. Products from this analysis can assist water managers in assessing the effect of breaching dikes and changing surface-water stage. The study area is in the approximate former northern margins of Upper Klamath and Agency Lakes in the Wood River Valley.

Measurements of Intra-Aortic Balloon Wall Movement During Inflation and Deflation: Effects of Angulation.

PubMed

Bruti, Gianpaolo; Kolyva, Christina; Pepper, John R; Khir, Ashraf W

2015-08-01

The intra-aortic balloon pump (IABP) is a ventricular assist device that is used with a broad range of pre-, intra-, and postoperative patients undergoing cardiac surgery. Although the clinical efficacy of the IABP is well documented, the question of reduced efficacy when patients are nursed in the semi-recumbent position remains outstanding. The aim of the present work is therefore to investigate the underlying mechanics responsible for the loss of IABP performance when operated at an angle to the horizontal. Simultaneous recordings of balloon wall movement, providing an estimate of its diameter (D), and fluid pressure were taken at three sites along the intra-aortic balloon (IAB) at 0 and 45°. Flow rate, used for the calculation of displaced volume, was also recorded distal to the tip of the balloon. An in vitro experimental setup was used, featuring physiological impedances on either side of the IAB ends. IAB inflation at an angle of 45° showed that D increases at the tip of the IAB first, presenting a resistance to the flow displaced away from the tip of the balloon. The duration of inflation decreased by 15.5%, the inflation pressure pulse decreased by 9.6%, and volume decreased by 2.5%. Similarly, changing the position of the balloon from 0 to 45°, the balloon deflation became slower by 35%, deflation pressure pulse decreased by 14.7%, and volume suctioned was decreased by 15.2%. IAB wall movement showed that operating at 45° results in slower deflation compared with 0°. Slow wall movement, and changes in inflation and deflation onsets, result in a decreased volume displacement and pressure pulse generation. Operating the balloon at an angle to the horizontal, which is the preferred nursing position in intensive care units, results in reduced IAB inflation and deflation performance, possibly compromising its clinical benefits. Copyright © 2015 The Authors. Artificial Organs published by Wiley Periodicals, Inc. on behalf of International Center for

Identification of the heart wall and chamber based on temporal change of ultrasonic scatterer distribution

NASA Astrophysics Data System (ADS)

Takahashi, Kohei; Taki, Hirofumi; Kanai, Hiroshi

2017-07-01

In most current methods for evaluating the cardiac function by ultrasound, the heart wall area is identified manually by an examiner. To eliminate examiner dependence and to improve usability, an automatic heart wall identification method is desirable. Identification based on only echogenicity often fails because of low echogenicity of some areas of the heart wall. In the present study, to determine more essential features, we focused on the relative temporal change of ultrasonic scatterer distribution and proposed three features for identification of the heart wall and the chamber: cross-correlation of RF signals, that of envelopes, and spatial dispersion of movement vectors in small regions. In an in vivo experiment, using echogenicity and the three features, we identified the heart wall and the chamber in the left ventricular long-axis view, resulting in criteria of separability J of 1.69, 1.40, and 3.02 using these features compared with the result of 0.979 using echogenicity.

Comparison of grey matter volume and thickness for analysing cortical changes in chronic schizophrenia: a matter of surface area, grey/white matter intensity contrast, and curvature.

PubMed

Kong, Li; Herold, Christina J; Zöllner, Frank; Salat, David H; Lässer, Marc M; Schmid, Lena A; Fellhauer, Iven; Thomann, Philipp A; Essig, Marco; Schad, Lothar R; Erickson, Kirk I; Schröder, Johannes

2015-02-28

Grey matter volume and cortical thickness are the two most widely used measures for detecting grey matter morphometric changes in various diseases such as schizophrenia. However, these two measures only share partial overlapping regions in identifying morphometric changes. Few studies have investigated the contributions of the potential factors to the differences of grey matter volume and cortical thickness. To investigate this question, 3T magnetic resonance images from 22 patients with schizophrenia and 20 well-matched healthy controls were chosen for analyses. Grey matter volume and cortical thickness were measured by VBM and Freesurfer. Grey matter volume results were then rendered onto the surface template of Freesurfer to compare the differences from cortical thickness in anatomical locations. Discrepancy regions of the grey matter volume and thickness where grey matter volume significantly decreased but without corresponding evidence of cortical thinning involved the rostral middle frontal, precentral, lateral occipital and superior frontal gyri. Subsequent region-of-interest analysis demonstrated that changes in surface area, grey/white matter intensity contrast and curvature accounted for the discrepancies. Our results suggest that the differences between grey matter volume and thickness could be jointly driven by surface area, grey/white matter intensity contrast and curvature. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Augmenting groundwater monitoring networks near landfills with slurry cutoff walls.

PubMed

Hudak, Paul F

2004-01-01

This study investigated the use of slurry cutoff walls in conjunction with monitoring wells to detect contaminant releases from a solid waste landfill. The 50 m wide by 75 m long landfill was oriented oblique to regional groundwater flow in a shallow sand aquifer. Computer models calculated flow fields and the detection capability of six monitoring networks, four including a 1 m wide by 50 m long cutoff wall at various positions along the landfill's downgradient boundaries and upgradient of the landfill. Wells were positioned to take advantage of convergent flow induced downgradient of the cutoff walls. A five-well network with no cutoff wall detected 81% of contaminant plumes originating within the landfill's footprint before they reached a buffer zone boundary located 50 m from the landfill's downgradient corner. By comparison, detection efficiencies of networks augmented with cutoff walls ranged from 81 to 100%. The most efficient network detected 100% of contaminant releases with four wells, with a centrally located, downgradient cutoff wall. In general, cutoff walls increased detection efficiency by delaying transport of contaminant plumes to the buffer zone boundary, thereby allowing them to increase in size, and by inducing convergent flow at downgradient areas, thereby funneling contaminant plumes toward monitoring wells. However, increases in detection efficiency were too small to offset construction costs for cutoff walls. A 100% detection efficiency was also attained by an eight-well network with no cutoff wall, at approximately one-third the cost of the most efficient wall-augmented network.

Tokamak experimental power reactor conceptual design. Volume II

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

Not Available

1976-08-01

Volume II contains the following appendices: (1) summary of EPR design parameters, (2) impurity control, (3) plasma computational models, (4) structural support system, (5) materials considerations for the primary energy conversion system, (6) magnetics, (7) neutronics penetration analysis, (8) first wall stress analysis, (9) enrichment of isotopes of hydrogen by cryogenic distillation, and (10) noncircular plasma considerations. (MOW)

Control of supersonic wind-tunnel noise by laminarization of nozzle-wall boundary layer

NASA Technical Reports Server (NTRS)

Beckwith, I. E.; Harvey, W. D.; Harris, J. E.; Holley, B. B.

1973-01-01

One of the principal design requirements for a quiet supersonic or hypersonic wind tunnel is to maintain laminar boundary layers on the nozzle walls and thereby reduce disturbance levels in the test flow. The conditions and apparent reasons for laminar boundary layers which have been observed during previous investigations on the walls of several nozzles for exit Mach numbers from 2 to 20 are reviewed. Based on these results, an analysis and an assessment of nozzle design requirements for laminar boundary layers including low Reynolds numbers, high acceleration, suction slots, wall temperature control, wall roughness, and area suction are presented.

25. NORTH TRAINING WALL, EAST SECTION, SIDE WALL CONSTRUCTION, LOOKING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

25. NORTH TRAINING WALL, EAST SECTION, SIDE WALL CONSTRUCTION, LOOKING WEST FROM A POINT ABOUT 500 FEET FROM THE MIDDLE HARBOR PARK FISHING PIER. (Panoramic view 1 of 2). - Oakland Harbor Training Walls, Mouth of Federal Channel to Inner Harbor, Oakland, Alameda County, CA

Volume 3 - Area Sources and Area Source Method Abstracts

EPA Pesticide Factsheets

Nonpoint (area) source emission reference materials from the EIIP. Provides nonpoint source guidance on planning, emissions estimation, data collection, inventory documentation and reporting, and quality assurance/quality control.

Wind tunnel wall interference

NASA Technical Reports Server (NTRS)

Newman, Perry A.; Mineck, Raymond E.; Barnwell, Richard W.; Kemp, William B., Jr.

1986-01-01

About a decade ago, interest in alleviating wind tunnel wall interference was renewed by advances in computational aerodynamics, concepts of adaptive test section walls, and plans for high Reynolds number transonic test facilities. Selection of NASA Langley cryogenic concept for the National Transonic Facility (NTF) tended to focus the renewed wall interference efforts. A brief overview and current status of some Langley sponsored transonic wind tunnel wall interference research are presented. Included are continuing efforts in basic wall flow studies, wall interference assessment/correction procedures, and adaptive wall technology.

Skyrmion domain wall collision and domain wall-gated skyrmion logic

NASA Astrophysics Data System (ADS)

Xing, Xiangjun; Pong, Philip W. T.; Zhou, Yan

2016-08-01

Skyrmions and domain walls are significant spin textures of great technological relevance to magnetic memory and logic applications, where they can be used as carriers of information. The unique topology of skyrmions makes them display emergent dynamical properties as compared with domain walls. Some studies have demonstrated that the two topologically inequivalent magnetic objects could be interconverted by using cleverly designed geometric structures. Here, we numerically address the skyrmion domain wall collision in a magnetic racetrack by introducing relative motion between the two objects based on a specially designed junction. An electric current serves as the driving force that moves a skyrmion toward a trapped domain wall pair. We see different types of collision dynamics depending on the driving parameters. Most importantly, the modulation of skyrmion transport using domain walls is realized in this system, allowing a set of domain wall-gated logical NOT, NAND, and NOR gates to be constructed. This work provides a skyrmion-based spin-logic architecture that is fully compatible with racetrack memories.

Plasma volume methodology: Evans blue, hemoglobin-hematocrit, and mass density transformations

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.; Hinghofer-Szalkay, H.

1985-01-01

Methods for measuring absolute levels and changes in plasma volume are presented along with derivations of pertinent equations. Reduction in variability of the Evans blue dye dilution technique using chromatographic column purification suggests that the day-to-day variability in the plasma volume in humans is less than + or - 20 m1. Mass density determination using the mechanical-oscillator technique provides a method for measuring vascular fluid shifts continuously for assessing the density of the filtrate, and for quantifying movements of protein across microvascular walls. Equations for the calculation of volume and density of shifted fluid are presented.

Near Wall Dynamics in Colloidal Suspensions Studied by Evansescent Wave Dynamic Light Scattering

NASA Astrophysics Data System (ADS)

Lang, Peter R.

2011-03-01

The dynamics of dispersed colloidal particles is slowed down, and becomes anisotropic in the ultimate vicinity of a flat wall due to the wall drag effect. Although theoretically predicted in the early 20th century, experimental verification of this effect for Brownian particles became possible only in the late 80s. Since then a variety of experimental investigations on near wall Brownian dynamics by evanescent wave dynamic light scattering (EWDLS) has been published. In this contribution the method of EWDLS will be briefly introduced, experiments at low and high colloid concentration for hard-sphere suspensions, and the theoretical prediction for measured initial slopes of correlation functions will be discussed. On increasing the particle concentration the influence of the wall drag effect is found to diminishes gradually, until it becomes negligible at volume fractions above ϕ 0.35. The effect that a wall exerts on the orientational dynamics was investigated for different kinds of colloids. Experiments, simulations and a virial expansion theory show that rotational dynamics is slowed down as well. However, the effect is prominent in EWDLS only if the particles' short axis is of the order of the evanescent wave penetration depth. The author acknowledges financial support from the EU through FP7, project Nanodirect (Grant 395 No. NMP4-SL-2008-213948).

Corpus Callosum Area and Brain Volume in Autism Spectrum Disorder: Quantitative Analysis of Structural MRI from the ABIDE Database

ERIC Educational Resources Information Center

Kucharsky Hiess, R.; Alter, R.; Sojoudi, S.; Ardekani, B. A.; Kuzniecky, R.; Pardoe, H. R.

2015-01-01

Reduced corpus callosum area and increased brain volume are two commonly reported findings in autism spectrum disorder (ASD). We investigated these two correlates in ASD and healthy controls using T1-weighted MRI scans from the Autism Brain Imaging Data Exchange (ABIDE). Automated methods were used to segment the corpus callosum and intracranial…

Vascular wall flow-induced forces in a progressively enlarged aneurysm model.

PubMed

Neofytou, Panagiotis; Tsangaris, Sokrates; Kyriakidis, Michalis

2008-12-01

The current study is focused on the numerical investigation of the flow field induced by the unsteady flow in the vicinity of an abdominal aortic aneurysm model. The computational fluid dynamics code used is based on the finite volume method, and it has already been used in various bioflow studies. For modelling the rheological behaviour of blood, the Quemada non-Newtonian model is employed, which is suitable for simulating the two-phase character of blood namely a suspension of blood cells in plasma. For examining its non-Newtonian effects a comparison with a corresponding Newtonian flow is carried out. Furthermore, the investigation is focused on the distribution of the flow-induced forces on the interior wall of the aneurysm and in order to study the development of the distribution with the gradual enlargement of the aneurysm, three different degrees of aneurysm-growth have been assumed. Finally and for examining the effect of the distribution on the aneurysm growth, a comparison is made between the pressure and wall shear-stress distributions at the wall for each growth-degree.

Cell wall microstructure, pore size distribution and absolute density of hemp shiv

PubMed Central

Lawrence, M.; Ansell, M. P.; Hussain, A.

2018-01-01

This paper, for the first time, fully characterizes the intrinsic physical parameters of hemp shiv including cell wall microstructure, pore size distribution and absolute density. Scanning electron microscopy revealed microstructural features similar to hardwoods. Confocal microscopy revealed three major layers in the cell wall: middle lamella, primary cell wall and secondary cell wall. Computed tomography improved the visualization of pore shape and pore connectivity in three dimensions. Mercury intrusion porosimetry (MIP) showed that the average accessible porosity was 76.67 ± 2.03% and pore size classes could be distinguished into micropores (3–10 nm) and macropores (0.1–1 µm and 20–80 µm). The absolute density was evaluated by helium pycnometry, MIP and Archimedes' methods. The results show that these methods can lead to misinterpretation of absolute density. The MIP method showed a realistic absolute density (1.45 g cm−3) consistent with the density of the known constituents, including lignin, cellulose and hemi-cellulose. However, helium pycnometry and Archimedes’ methods gave falsely low values owing to 10% of the volume being inaccessible pores, which require sample pretreatment in order to be filled by liquid or gas. This indicates that the determination of the cell wall density is strongly dependent on sample geometry and preparation. PMID:29765652

PBF (PER620) interior, basement level. Concrete wall shows outline of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PBF (PER-620) interior, basement level. Concrete wall shows outline of reactor basin. Sign says, "Flashing Light - Reactor On - Evacuate Area." Date: May 2004. INEEL negative no. HD-41-5-3 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

Nanotubes May Break Through "Chip Wall"

NASA Technical Reports Server (NTRS)

Laufenberg, Larry

2003-01-01

In 1965, just four years after the first planar integrated circuit (IC) was discovered, Cordon Moore observed that the number of transistors per integrated circuit had grown exponentially. He predicted that this would continue, and the media soon began to call his prophesy "Moore's Law" For nearly forty years, Moore's Law has been validated by the technological progress achieved in the semiconductor industry. Now, however, industry experts are warning of a "Red Brick Wall" that may soon block the continued scaling predicted by by Moore's Law. The "red bricks" in the wall are those areas of technical challenge for which no known manufacturable solution exists. One such "brick" is the challenge of finding a new material and processing technology to replace the metals used today to interconnect transistors on a chip.

Chronic laminitis: strategic hoof wall resection.

PubMed

Rucker, Amy

2010-04-01

In the chronic-laminitic foot, severe soft-tissue compression and compromised circulation can result in osteitis and sepsis at the margin of the distal phalanx. Resultant inflammation and sepsis may cause the coronary corium to swell, drain, or separate from the hoof capsule, usually within 8 weeks of laminitis onset. Slow-onset cases of soft-tissue impingement can develop secondary to distal phalanx displacement due to lack of wall attachment. With either presentation, partial upper wall resection is required to reverse compression and vascular impingement by the hoof capsule. If the pathology is not overwhelming, the area reepithelializes and grows attached tubular horn. Firm bandaging and restricted exercise until tubular horn has regrown enhances recovery and the return of a strong hoof. Copyright 2010 Elsevier Inc. All rights reserved.

Right atrial indexed volume in healthy adult population: reference values for two-dimensional and three-dimensional echocardiographic measurements.

PubMed

Moreno, Joel; Pérez de Isla, Leopoldo; Campos, Nellys; Guinea, Juan; Domínguez-Perez, Laura; Saltijeral, Adriana; Lennie, Vera; Quezada, Maribel; de Agustín, Alberto; Marcos-Alberca, Pedro; Mahía, Patricia; García-Fernández, Miguel Ángel; Macaya, Carlos

2013-07-01

Current guidelines do not recommend routine assessment of right atrial volume due to the lack of standardized data. Three-dimensional wall-motion tracking (3D-WMT) is a new technology that allows us to calculate volumes without any geometric assumptions. The aim of this study was to define the indexed reference values for two-dimensional echocardiography (2D-echo) and 3D-WMT in adult healthy population and to assess the intermethod, intra- and interobserver agreement. Prospective study. Nonselected healthy subjects were enrolled. Every patient underwent a 2D-echo and a 3D-WMT examination. 2D-echo right atrial volume was obtained by using the area-length method (A-L) from four- and two-chamber view. 3D-echo volumes were assessed by 3D-WMT. Values were indexed by the patient's body surface area. Sixty consecutive healthy subjects were enrolled. Mean age was 57 ± 12-years old and 27 patients (45%) were male. Average indexed right atrial volume obtained by 2D-echo and 3D-echo was 16.76 ± 8.15 mL/m(2) and 19.05 ± 6.87 mL/m(2) , respectively. Univariate linear regression analysis between 2D-echo and 3D-echo right atrial volumes shows a weak correlation between right atrial volume obtained with 2D-echo compared with 3D-WMT (r = 0.29, CI 95% 0.029-0.66, P = 0.033). The agreement analysis shows a similar result (intraclass correlation coefficient [ICC] = 0.28). The intra- and interobserver agreement analysis showed a better agreement when using 3D-WMT. This is the first study that reports the reference indexed right atrial volume values by means of 2D-echo and 3D-echo in healthy population. 3D-WMT is a feasible and reproducible method to determine right atrial volume. © 2013, Wiley Periodicals, Inc.

Analysis of the plasma-wall interaction in the Heliotron E device

NASA Astrophysics Data System (ADS)

Motojima, O.; Mizuuchi, T.; Besshou, S.; Iiyoshi, A.; Uo, K.; Yamashina, T.; Mohri, M.; Satake, T.; Hashiba, M.; Amemiya, S.; Miwa, H.

1984-12-01

The plasma-wall interaction (PWI) of the currentless plasmas with temperature To, Tio ≤ 1.1 keV, density N¯e = (2-10)× 1013/cm3, and volume-averaged beta value of β$¯≤ 2% was investigated. We have observed that PWI took place mainly where the divertor field line intersected the chamber wall (called divertor traces). Boundary plasmas were measured with electrostatic probes, which showed the presence of the divertor region with the parameters in the range of Ned = 1010-1011/cm3 and Ted = 10-50 eV. Surface analysis techniques (ESCA, AES, and RBS) were applied to analyze the surface probes (Si, graphite and stainless steel) and the test pieces (SiC, TiC, and stainless steel), which were irradiated by plasmas for short and long times respectively.

52. SUPREME COURT ROOM, SOUTH WALL, WEST WINDOW DETAIL OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

52. SUPREME COURT ROOM, SOUTH WALL, WEST WINDOW DETAIL OF EAST SPLAYED JAMB AND TRIM (NOTE REPAIRED AREAS) - Independence Hall Complex, Independence Hall, 500 Chestnut Street, Philadelphia, Philadelphia County, PA

PBF Reactor Building (PER620). Camera faces south along west wall. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PBF Reactor Building (PER-620). Camera faces south along west wall. Gap between native lava rock and concrete basement walls is being backfilled and compacted. Wire mesh protects workers from falling rock. Note penetrations for piping that will carry secondary coolant water to Cooling Tower. Photographer: Holmes. Date: June 15, 1967. INEEL negative no. 67-3665 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

Synthesis and characterization of high-surface-area millimeter-sized silica beads with hierarchical multi-modal pore structure by the addition of agar

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

Han, Yosep; Choi, Junhyun; Tong, Meiping, E-mail: tongmeiping@iee.pku.edu.cn

2014-04-01

Millimeter-sized spherical silica foams (SSFs) with hierarchical multi-modal pore structure featuring high specific surface area and ordered mesoporous frameworks were successfully prepared using aqueous agar addition, foaming and drop-in-oil processes. The pore-related properties of the prepared spherical silica (SSs) and SSFs were systematically characterized by field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), small-angle X-ray diffraction (SAXRD), Hg intrusion porosimetry, and N{sub 2} adsorption–desorption isotherm measurements. Improvements in the BET surface area and total pore volume were observed at 504 m{sup 2} g{sup −1} and 5.45 cm{sup 3} g{sup −1}, respectively, after an agar addition and foaming process. Despitemore » the increase in the BET surface area, the mesopore wall thickness and the pore size of the mesopores generated from the block copolymer with agar addition were unchanged based on the SAXRD, TEM, and BJH methods. The SSFs prepared in the present study were confirmed to have improved BET surface area and micropore volume through the agar loading, and to exhibit interconnected 3-dimensional network macropore structure leading to the enhancement of total porosity and BET surface area via the foaming process. - Highlights: • Millimeter-sized spherical silica foams (SSFs) are successfully prepared. • SSFs exhibit high BET surface area and ordered hierarchical pore structure. • Agar addition improves BET surface area and micropore volume of SSFs. • Foaming process generates interconnected 3-D network macropore structure of SSFs.« less

Adaptive wall technology for minimization of wall interferences in transonic wind tunnels

NASA Technical Reports Server (NTRS)

Wolf, Stephen W. D.

1988-01-01

Modern experimental techniques to improve free air simulations in transonic wind tunnels by use of adaptive wall technology are reviewed. Considered are the significant advantages of adaptive wall testing techniques with respect to wall interferences, Reynolds number, tunnel drive power, and flow quality. The application of these testing techniques relies on making the test section boundaries adjustable and using a rapid wall adjustment procedure. A historical overview shows how the disjointed development of these testing techniques, since 1938, is closely linked to available computer support. An overview of Adaptive Wall Test Section (AWTS) designs shows a preference for use of relatively simple designs with solid adaptive walls in 2- and 3-D testing. Operational aspects of AWTS's are discussed with regard to production type operation where adaptive wall adjustments need to be quick. Both 2- and 3-D data are presented to illustrate the quality of AWTS data over the transonic speed range. Adaptive wall technology is available for general use in 2-D testing, even in cryogenic wind tunnels. In 3-D testing, more refinement of the adaptive wall testing techniques is required before more widespread use can be planned.

Relative Distribution of Quadriceps Head Anatomical Cross-Sectional Areas and Volumes – Sensitivity to Pain and to Training Intervention

PubMed Central

Sattler, M; Dannhauer, T; Ring-Dimitriou, S; Sänger, AM; Wirth, W; Hudelmaier, M; Eckstein, F

2014-01-01

SUMMARY Introduction Quadriceps heads are important in biomechanical stabilization and in the pathogenesis osteoarthritis of the knee. This is the first study to explore the relative distribution of quadriceps head anatomical cross-sectional areas (ACSA) and volumes, and their response to pain and to training intervention. Methods The relative proportions of quadriceps heads were determined in 48 Osteoarthritis Initiative participants with unilateral pain (65% women; age 45–78y). Quadriceps head volumes were also measured in 35 untrained women (45–55y) before and after 12 week training intervention. Cross-sectional areas of the vastus medialis (VM), inter-medius (VIM), and lateralis (VL), and of the rectus femoris (RF) were determined from axial T1-weighted MR images. Results The proportion of the VM on the total quadriceps ACSA increased from proximal to distal. The difference in quadriceps ACSA of painful (vs. pain-free) limbs was −5.4% for the VM (p<0.001), −6.8% for the VL (p<0.01), −2.8% for the VIM (p=0.06), and +3.4% for the RF (p=0.67) but the VM/VL ratio was not significantly altered. The muscle volume increase during training intervention was +4.2% (p<0.05) for VM, +1.3% for VL, +2.0% for VIM (p<0.05) and +1.6% for RF. Conclusion The proportion of quadriceps head relative to total muscle ACSA and volume depends on the anatomical level studied. The results suggest that there may be a differential response of the quadriceps heads to pain-induced atrophy and to training-related hypertrophy. Studies in larger samples are needed to ascertain whether the observed differences in response to pain and training are statistically and clinically significant. PMID:25153247

Urban reconciliation ecology: the potential of living roofs and walls.

PubMed

Francis, Robert A; Lorimer, Jamie

2011-06-01

Reconciling human and non-human use of urban regions to support biological conservation represents a major challenge for the 21st century. The concept of reconciliation ecology, by which the anthropogenic environment may be modified to encourage non-human use and biodiversity preservation without compromising societal utilization, potentially represents an appropriate paradigm for urban conservation given the generally poor opportunities that exist for reserve establishment and ecological restoration in urban areas. Two habitat improvement techniques with great potential for reconciliation ecology in urban areas are the installation of living roofs and walls, which have been shown to support a range of taxa at local scales. This paper evaluates the reconciliation potential of living roofs and walls, in particular highlighting both ecological and societal limitations that need to be overcome for application at the landscape scale. We further consider that successful utilization of living roofs and walls for urban reconciliation ecology will rely heavily on the participation of urban citizens, and that a 'citizen science' model is needed to facilitate public participation and support and to create an evidence base to determine their effectiveness. Living roofs and walls are just one aspect of urban reconciliation ecology, but are particularly important 'bottom-up' techniques for improving urban biodiversity that can be performed directly by the citizenry. Copyright © 2011 Elsevier Ltd. All rights reserved.

Cell wall properties in Oryza sativa influence mesophyll CO2 conductance.

PubMed

Ellsworth, Patrícia V; Ellsworth, Patrick Z; Koteyeva, Nuria K; Cousins, Asaph B

2018-04-20

Diffusion of CO 2 from the leaf intercellular air space to the site of carboxylation (g m ) is a potential trait for increasing net rates of CO 2 assimilation (A net ), photosynthetic efficiency, and crop productivity. Leaf anatomy plays a key role in this process; however, there are few investigations into how cell wall properties impact g m and A net . Online carbon isotope discrimination was used to determine g m and A net in Oryza sativa wild-type (WT) plants and mutants with disruptions in cell wall mixed-linkage glucan (MLG) production (CslF6 knockouts) under high- and low-light growth conditions. Cell wall thickness (T cw ), surface area of chloroplast exposed to intercellular air spaces (S c ), leaf dry mass per area (LMA), effective porosity, and other leaf anatomical traits were also analyzed. The g m of CslF6 mutants decreased by 83% relative to the WT, with c. 28% of the reduction in g m explained by S c . Although A net /LMA and A net /Chl partially explained differences in A net between genotypes, the change in cell wall properties influenced the diffusivity and availability of CO 2 . The data presented here indicate that the loss of MLG in CslF6 plants had an impact on g m and demonstrate the importance of cell wall effective porosity and liquid path length on g m . © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

VIEW OF GRAPHITE BLOCK SHIELDING WALL (NOT IN ORIGINAL LOCATION), ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF GRAPHITE BLOCK SHIELDING WALL (NOT IN ORIGINAL LOCATION), LEVEL -15’, LABORATORY/OFFICE WING, LOOKING SOUTHWEST - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC

Wall shear stress in intracranial aneurysms and adjacent arteries☆

PubMed Central

Wang, Fuyu; Xu, Bainan; Sun, Zhenghui; Wu, Chen; Zhang, Xiaojun

2013-01-01

Hemodynamic parameters play an important role in aneurysm formation and growth. However, it is difficult to directly observe a rapidly growing de novo aneurysm in a patient. To investigate possible associations between hemodynamic parameters and the formation and growth of intracranial aneurysms, the present study constructed a computational model of a case with an internal carotid artery aneurysm and an anterior communicating artery aneurysm, based on the CT angiography findings of a patient. To simulate the formation of the anterior communicating artery aneurysm and the growth of the internal carotid artery aneurysm, we then constructed a model that virtually removed the anterior communicating artery aneurysm, and a further two models that also progressively decreased the size of the internal carotid artery aneurysm. Computational simulations of the fluid dynamics of the four models were performed under pulsatile flow conditions, and wall shear stress was compared among the different models. In the three aneurysm growth models, increasing size of the aneurysm was associated with an increased area of low wall shear stress, a significant decrease in wall shear stress at the dome of the aneurysm, and a significant change in the wall shear stress of the parent artery. The wall shear stress of the anterior communicating artery remained low, and was significantly lower than the wall shear stress at the bifurcation of the internal carotid artery or the bifurcation of the middle cerebral artery. After formation of the anterior communicating artery aneurysm, the wall shear stress at the dome of the internal carotid artery aneurysm increased significantly, and the wall shear stress in the upstream arteries also changed significantly. These findings indicate that low wall shear stress may be associated with the initiation and growth of aneurysms, and that aneurysm formation and growth may influence hemodynamic parameters in the local and adjacent arteries. PMID:25206394

The effects of nicotine administration on the pathophysiology of rat aortic wall.

PubMed

Kugo, H; Zaima, N; Tanaka, H; Urano, T; Unno, N; Moriyama, T

2017-01-01

Abdominal aortic aneurysm (AAA) is the progressive dilation of the abdominal aorta. Nicotine is reported to be associated with the development and rupture of AAA, but the pathological effects of nicotine on normal rat aorta have not been determined. We investigated pathological changes in the aortic wall of rats caused by the administration of nicotine. Nicotine administration weakened the vascular wall, increased gelatinolytic activity and promoted the destruction of elastin and collagen in the rat abdominal aorta. There were no differences in the areas positive for matrix metalloproteinase (MMP)-2 and MMP-9 between the control and nicotine treated groups. The areas positive for MMP-12 in the nicotine group were significantly greater than for the control group. Gelatinolytic activity in the aortic wall was increased significantly in the nicotine group. Our findings suggest that MMP-12 is sensitive to nicotine exposure in rats.

Survival after Lung Volume Reduction in Chronic Obstructive Pulmonary Disease

PubMed Central

Hogg, James C.; Chu, Fanny S. F.; Tan, Wan C.; Sin, Don D.; Patel, Sanjay A.; Pare, Peter D.; Martinez, Fernando J.; Rogers, Robert M.; Make, Barry J.; Criner, Gerard J.; Cherniack, Reuben M.; Sharafkhaneh, Amir; Luketich, James D.; Coxson, Harvey O.; Elliott, W. Mark; Sciurba, Frank C.

2007-01-01

Rationale: COPD is associated with reduced life expectancy. Objectives: To determine the association between small airway pathology and long-term survival after lung volume reduction in chronic obstructive pulmonary disease (COPD) and the effect of corticosteroids on this pathology. Methods: Patients with severe (GOLD-3) and very severe (GOLD-4) COPD (n = 101) were studied after lung volume reduction surgery. Respiratory symptoms, quality of life, pulmonary function, exercise tolerance, chest radiology, and corticosteroid treatment status were assessed preoperatively. The severity of luminal occlusion, wall thickening, and the presence of small airways containing lymphoid follicles were determined in resected lung tissue. Kaplan-Meier survival analysis and Cox proportional hazards models were used to determine the relationship between survival and small airway pathology. The effect of corticosteroids on this pathology was assessed by comparing treated and untreated groups. Measurements and Main Results: The quartile of subjects with the greatest luminal occlusion, adjusted for covariates, died earlier than subjects who had the least occlusion (hazard ratio, 3.28; 95% confidence interval, 1.55–6.92; P = 0.002). There was a trend toward a reduction in the number of airways containing lymphoid follicles (P = 0.051) in those receiving corticosteroids, with a statistically significant difference between the control and oral ± inhaled corticosteroid–treated groups (P = 0.019). However, corticosteroid treatment had no effect on airway wall thickening or luminal occlusion. Conclusions: Occlusion of the small airways by inflammatory exudates containing mucus is associated with early death in patients with severe emphysema treated by lung volume reduction surgery. Corticosteroid treatment dampens the host immune response in these airways by reducing lymphoid follicles without changing wall thickening and luminal occlusion. PMID:17556723

Carbon deposition model for oxygen-hydrocarbon combustion, volume 1

NASA Technical Reports Server (NTRS)

Hernandez, R.; Ito, J. I.; Niiya, K. Y.

1987-01-01

Presented are details of the design, fabrication, and testing of subscale hardware used in the evaluation of carbon deposition characteristics of liquid oxygen and three hydrocarbon fuels for both main chamber and preburner/gas generator operating conditions. In main chamber conditions, the deposition of carbon on the combustion chamber wall was investigated at mixture ratios of 2.0 to 4.0 and at pressures of 1000 to 1500 psia. No carbon deposition on the chamber walls was detected at these main chamber mixture ratios. In preburner/gas generator operating conditions, the deposition of carbon on the turbine simulator tubes was evaluated at mixture ratios of 0.20 to 0.60 and at chamber pressures of 720 to 1650 psia. The results of the tests showed carbon deposition rate to be a strong function of mixture ratio and a weak function of chamber pressure. Further analyses evaluated the operational consequences of carbon deposition on preburner/gas generator performance. The report is in two volumes, of which this is Volume 1 covering the main body of the report plus Appendixes A through D.

Estimating the volume of Alpine glacial lakes

NASA Astrophysics Data System (ADS)

Cook, S. J.; Quincey, D. J.

2015-09-01

Supraglacial, moraine-dammed and ice-dammed lakes represent a potential glacial lake outburst flood (GLOF) threat to downstream communities in many mountain regions. This has motivated the development of empirical relationships to predict lake volume given a measurement of lake surface area obtained from satellite imagery. Such relationships are based on the notion that lake depth, area and volume scale predictably. We critically evaluate the performance of these existing empirical relationships by examining a global database of measured glacial lake depths, areas and volumes. Results show that lake area and depth are not always well correlated (r2 = 0.38), and that although lake volume and area are well correlated (r2 = 0.91), there are distinct outliers in the dataset. These outliers represent situations where it may not be appropriate to apply existing empirical relationships to predict lake volume, and include growing supraglacial lakes, glaciers that recede into basins with complex overdeepened morphologies or that have been deepened by intense erosion, and lakes formed where glaciers advance across and block a main trunk valley. We use the compiled dataset to develop a conceptual model of how the volumes of supraglacial ponds and lakes, moraine-dammed lakes and ice-dammed lakes should be expected to evolve with increasing area. Although a large amount of bathymetric data exist for moraine-dammed and ice-dammed lakes, we suggest that further measurements of growing supraglacial ponds and lakes are needed to better understand their development.

On investigating wall shear stress in two-dimensional plane turbulent wall jets