Reference Curves for the Aortic Area by Age

The sustainability concerns of concrete construction are focused both on the materials’ eco-efficiency and on the structures’ durability. The present work focuses on the characterization of low cement concrete (LCC), regarding time-dependent and durability properties. LCC studies which explore the influence of the formulation parameters, such as the W/C (water/cement ratio), W/Ceq, (which represents the mass ratio between water and equivalent cement), W/B (water/binder) ratio, and the reference curves, on the aforementioned properties are limited. Thus, several LCC mixtures were formulated considering two dosages of binder powder, 350 and 250 kg/m3, the former with very plastic consistency and the latter with dry consistency, which were combined with a large spectrum of cement replacement rates (up to 70%), through adding fly ash and limestone filler, and with different compactness levels. The main objectives were to study the influence of the formulation parameters on the properties: shrinkage and creep, accelerated carbonation and water absorption, by capillarity, and by immersion. The lifetime of structures produced with the studied LCC was estimated, considering the durability performance, regarding the carbonation effect on the possible corrosion of the steel reinforcement. LCC mixtures with reduced cement dosage and high compactness, despite the high W/C ratios, have low shrinkage and those with higher strength have reduced creep, however depending on W/Ceq ratio. Those mixtures can be formulated and produced presenting good performance regarding carbonation resistance and, consequently, a long lifetime, which is mandatory for a sustainable construction. LCC with 175 kg/m3 of cement dosage is an example with higher lifetime than current concrete with 250 kg/m3 of cement; depending on the XC exposure classes (corrosion induced by carbonation), the amount of cement can be reduced between 37.5% and 42%, since the LCC with 175 kg/m3 of cement allows reducing the concrete cover below the minimum recommended, ensuring simultaneously the required lifetime for current and special structures.

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Use of Cardiac Magnetic Resonance Imaging Based Measurements of Inferior Vena Cava Cross-Sectional Area in the Diagnosis of Pericardial Constriction

Canadian Association of Radiologists Journal ◽

10.1016/j.carj.2014.12.007 ◽

2015 ◽

Vol 66 (3) ◽

pp. 231-237 ◽

Cited By ~ 2

Author(s):

Kate Hanneman ◽

Paaladinesh Thavendiranathan ◽

Elsie T. Nguyen ◽

Hadas Moshonov ◽

Rachel Wald ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Cardiac Magnetic Resonance ◽

Inferior Vena ◽

Vena Cava ◽

Area Ratio ◽

Cross Sectional Area ◽

Sectional Area ◽

Resonance Imaging ◽

Cross Sectional ◽

Aortic Area

Purpose To evaluate the value of cardiac magnetic resonance imaging (MRI)–based measurements of inferior vena cava (IVC) cross-sectional area in the diagnosis of pericardial constriction. Methods Patients who had undergone cardiac MRI for evaluation of clinically suspected pericardial constriction were identified retrospectively. The diagnosis of pericardial constriction was established by clinical history, echocardiography, cardiac catheterization, intraoperative findings, and/or histopathology. Cross-sectional areas of the suprahepatic IVC and descending aorta were measured on a single axial steady-state free-precession (SSFP) image at the level of the esophageal hiatus in end-systole. Logistic regression and receiver-operating curve (ROC) analyses were performed. Results Thirty-six patients were included; 50% (n = 18) had pericardial constriction. Mean age was 53.9 ± 15.3 years, and 72% (n = 26) were male. IVC area, ratio of IVC to aortic area, pericardial thickness, and presence of respirophasic septal shift were all significantly different between patients with constriction and those without ( P < .001 for all). IVC to aortic area ratio had the highest odds ratio for the prediction of constriction (1070, 95% confidence interval [8.0-143051], P = .005). ROC analysis illustrated that IVC to aortic area ratio discriminated between those with and without constriction with an area under the curve of 0.96 (95% confidence interval [0.91-1.00]). Conclusions In patients referred for cardiac MRI assessment of suspected pericardial constriction, measurement of suprahepatic IVC cross-sectional area may be useful in confirming the diagnosis of constriction when used in combination with other imaging findings, including pericardial thickness and respirophasic septal shift.

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Alternative reference curves for evaluation of the impact sound insulation between dwellings

Journal of Sound and Vibration ◽

10.1016/s0022-460x(85)80149-8 ◽

1985 ◽

Vol 102 (3) ◽

pp. 381-402 ◽

Cited By ~ 27

Author(s):

K. Bodlund

Keyword(s):

Sound Insulation ◽

Reference Curves ◽

The Impact

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Appropriateness of US and international BMI-for-age reference curves in defining adiposity among Israeli school children

European Journal of Pediatrics ◽

10.1007/s00431-006-0284-z ◽

2006 ◽

Vol 166 (6) ◽

pp. 573-578 ◽

Cited By ~ 8

Author(s):

Michael Huerta ◽

Michael Gdalevich ◽

Alla Tlashadze ◽

Shimon Scharf ◽

Menachem Schlezinger ◽

...

Keyword(s):

School Children ◽

Reference Curves

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Body mass index reference curves for the UK, 1990.

Archives of Disease in Childhood ◽

10.1136/adc.73.1.25 ◽

1995 ◽

Vol 73 (1) ◽

pp. 25-29 ◽

Cited By ~ 1273

Author(s):

T J Cole ◽

J V Freeman ◽

M A Preece

Keyword(s):

Body Mass Index ◽

Body Mass ◽

Reference Curves ◽

The Uk

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The chemostratigraphy and environmental significance of the Marlstone and Junction Bed (Beacon Limestone, Toarcian, Lower Jurassic, Dorset, UK)

Geological Magazine ◽

10.1017/s0016756821000972 ◽

2021 ◽

pp. 1-15

Author(s):

Hugh C. Jenkyns ◽

Sophie Macfarlane

Keyword(s):

Carbon Isotope ◽

Oxygen Isotopes ◽

Lower Jurassic ◽

Carbon And Oxygen Isotopes ◽

Oceanic Anoxic Event ◽

Nodular Limestone ◽

Anoxic Event ◽

Reference Curves ◽

High Degree ◽

Organic Rich Sediment

Abstract Two fallen blocks of the Marlstone and stratigraphically overlying Junction Bed sampled on the beach below Doghouse Cliff in Dorset, UK (Wessex Basin) have been examined for carbon and oxygen isotopes of bulk carbonate as well as for strontium, carbon and oxygen isotopes and Mg:Ca ratios in the contained belemnites. The sequence, which contains most of the Toarcian zones and subzones within a metre or less of grey to yellow to pink, red and brown fossil-rich nodular limestone, is extremely condensed and lithologically similar to pelagic red limestones of the Tethyan Jurassic that are locally mineralized with Fe-Mn oxyhydroxides (e.g., Rosso Ammonitico). Strontium-isotope ratios of the contained belemnites are compatible with existing reference curves and both blocks show a rise to more radiogenic values post-dating the Pliensbachian–Toarcian boundary. The high degree of correlation between the relatively negative carbon and oxygen isotopes of the bulk carbonate is compatible with significant diagenetic overprint, and contrasts with higher carbon-isotope values in coeval condensed coccolith-rich limestones elsewhere. Evidence for the characteristic signature of the Toarcian Oceanic Anoxic Event, as represented by organic-rich sediment, is absent, possibly owing to a stratigraphic gap. Both blocks exhibit abrupt carbon-isotope shifts to lower values, one of which could represent the limbs of an incompletely recorded negative excursion associated with the Toarcian Oceanic Anoxic Event. That the Toarcian Oceanic Anoxic Event was also a significant hyperthermal is illustrated in both blocks by a drop in oxygen-isotope values and rise in Mg:Ca ratios of belemnites close to the base of the Junction Bed in the lowest part of the serpentinum zone.

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Abstract P247: Ethnic Differences in Infrarenal Aortic Diameter and Area in a Population-Based Study

Circulation ◽

10.1161/circ.125.suppl_10.ap247 ◽

2012 ◽

Vol 125 (suppl_10) ◽

Author(s):

David E Timaran ◽

Eric B Rosero ◽

Adriana J Higuera ◽

Ron Peshock ◽

R James Valentine ◽

...

Keyword(s):

Body Size ◽

Ethnic Differences ◽

Population Based ◽

Aortic Diameter ◽

Hispanic Ethnicity ◽

Female Sex ◽

Abdominal Aortic ◽

Aortic Area ◽

Blacks And Whites ◽

Lower Height

Objective: Abdominal aortic aneurysms are defined as a 50% or greater increase in infrarenal aortic diameter (IAD). However, normal IAD has not been defined for all ethnic groups as minorities have been underrepresented in most studies. The aim of the study was to assess ethnic differences in IAD and infrarenal aortic area (AoA) adjusting for the effects of age, gender and body size in the general population. Methods: Participants (2,515) in a population based study underwent high-resolution magnetic resonance imaging (MRI) of the abdominal aorta. Analyses of variance and multiple regression analyses were used to assess the relationship between race/ethnicity, age, gender and body size and IAD and aortic area. Subjects with AAA detected by MRI (defined as IAD ≥ 3.0 cm) were excluded from the analysis. Results: Decreasing age, female sex, Hispanic ethnicity, and lower height were independent predictors of reduced IAD by multivariate linear regression (all P < 0.001). Of these, female sex and Hispanic ethnicity were the factors more strongly associated with aortic size. Female sex was associated with 0.27 cm reduction in IAD and Hispanic ethnicity with 0.39 cm reduction in IAD. Similarly, decreasing age, female sex, Hispanic ethnicity, and lower height were independent predictors of reduced AoA. Female sex was associated with a 51 cm 2 reduction in AoA and Hispanic ethnicity with 11.1 cm 2 reduction in AoA. Although Hispanics had higher BMI than blacks and whites ( P =.01), and lower height values than blacks and whites (P<.0001), IADs and AoAs were consistently lower among Hispanics. Conclusions: Ethnic differences exist in infrarenal aortic diameter. Despite larger body size, Hispanics have significantly lower IAD than blacks and whites in the general population. The reduced aortic size in Hispanics suggests that the thresholds for abdominal aortic aneurysm diagnosis, rupture and repair may be lower and need to be established.

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Point mass impulse-momentum model of the equine rotational fall

Comparative Exercise Physiology ◽

10.3920/cep190018 ◽

2019 ◽

Vol 15 (3) ◽

pp. 157-165

Author(s):

M.H. Foreman ◽

J.R. Engsberg ◽

J.H. Foreman

Keyword(s):

Point Mass ◽

Future Research ◽

Collision Time ◽

Mass Model ◽

Impact Forces ◽

Force Transfer ◽

Reference Curves ◽

Key Variables ◽

Cross Country ◽

Input Variables

Rotational falls are a serious cause of injury and death to horse and rider, particularly in the cross-country phase of eventing. The forces involved when horses galloping cross-country strike an immovable fence are unknown. The objective of this study was to mathematically model those forces using existing kinematic data measured from jumping horses. Data were obtained from published research using motion capture to measure mechanics about the center of gravity of the jumping horse at take-off. A convenience method from video evidence of rotational falls was used to estimate time of collision (Δt). A point mass model using equations of impulse-momentum and incorporating key variables was systematically implemented in Matlab (r2016a). The mean collision time (Δt=0.79s) produced horizontal, vertical, and resultant impact forces of 8,580, 8,245, and 12,158 N, respectively. Reference curves of impact forces were created for ranges of relevant input variables including collision time. Proportional relationships showed that shorter impact duration led to higher magnitude of force transfer between horse and obstacle. This study presents a preliminary range of collision forces based on a simplified model and numerous assumptions related to input variables. Future research should work to build upon these estimates through more complex modelling and data collection to enhance applicability for the design of cross-country safety devices.

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