Two-dimensional Measures Research Articles

385 Patients with Systemic Lupus Erythematosus With Normal Left Ventricular Ejection Fraction Demonstrate Impaired Left Ventricular Global Longitudinal Strain

Systemic lupus erythematosus (SLE) is a chronic inflammatory disease modulated by pro-inflammatory cytokines. This state results in a negative inotropic effect on cardiac myocytes and may result in myocardial dysfunction. Mean global longitudinal strain (GLS) is proposed to be a more sensitive measure of cardiac function compared to standard two-dimensional measures of left ventricular (LV) systolic function. We hypothesize SLE patients have subclinical cardiac dysfunction despite normal LV ejection fraction (LVEF) reflected by reduced mean LV-GLS. Consecutive patients (n=103) admitted to our hospital (2013-2018) with a past medical history of SLE were initially evaluated. Patients without a comprehensive transthoracic echocardiogram and those with cardiac disease or impaired LVEF <50% were excluded (n=52). A range of clinical and echocardiographic parameters, including mean LV-GLS, were examined in this cohort (n=51) and compared to age- and gender-matched controls (n=51). GLS was measured offline using vendor-independent software (TomTec Arena, Germany v4.6). There was no significant difference in baseline clinical characteristics and cardiovascular risk factor profiles between groups. Patients with SLE showed greater LV remodelling through a higher indexed LV Mass (g) (96±34 vs 72±20, p=0.01). Additionally, SLE patients had significantly lower GLS (%) (-16.7±2.8) when compared to healthy controls (-21.3±2) (p<0.0001) despite normal LVEF in both groups. Our results suggest that SLE patients show evidence of subclinical cardiac dysfunction, despite a normal LVEF and absence of cardiac disease. These patients may benefit from routine echocardiographic assessments and early cardiac preventative interventions.

Reliability of two-dimensional measures associated with bilateral drop-landing performance

The aim of this study was to establish the within-session reliability for two-dimensional (2D) video analysis of sagittal- and frontal-plane measures during bilateral drop-landing tasks. Thirty-nine recreational athletes (22 men, 17 women, age = 22 ± 4 years, height = 1.74 ± 0.15 m, body mass 70.2 ± 15.1 kg) performed five bilateral drop-landings from 50, 100 and 150% of maximum countermovement jump height, twice on the same day. Measures of reliability for initial contact angle, peak flexion angle and joint displacement for the hip, knee, and ankle joints, frontal-plane projection angles (FPPA), as well as inter-limb asymmetries in joint displacement were assessed. No systematic bias was present between trials (P&gt;0.05). All kinematic measurements showed relative reliability ranging from large to near perfect (ICC = 0.52–0.96). Absolute reliability ranged between measures, with CV% between 1.0–1.6% for initial contact angles, 1.9–7.9% for peak flexion angles, 5.3–22.4% for joint displacement, and 1.6–2.3% for FPPA. Absolute reliability for inter-limb asymmetries in joint displacement were highly variable, with minimal detectable change values ranging from 6.0–13.2°. Therefore, 2D video analysis is a reliable tool for numerous measures related to the performance of bilateral drop-landings.

How to Obtain Maximal and Minimal Subranges of Two-Dimensional Vector Measures

Abstract Let (X, ℱ) be a measurable space with a nonatomic vector measure µ =(µ 1, µ 2). Denote by R(Y) the subrange R(Y)= {µ(Z): Z ∈ ℱ, Z ⊆ Y }. For a given p ∈ µ(ℱ) consider a family of measurable subsets ℱ p = {Z ∈ ℱ : µ(Z)= p}. Dai and Feinberg proved the existence of a maximal subset Z* ∈ Fp having the maximal subrange R(Z*) and also a minimal subset M* ∈ ℱ p with the minimal subrange R(M*). We present a method of obtaining the maximal and the minimal subsets. Hence, we get simple proofs of the results of Dai and Feinberg.

Ontogenetic changes to bone microstructure in an archaeologically derived sample of human ribs

There is considerable variation in the gross morphology and tissue properties among the bones of human infants, children, adolescents, and adults. Using 18 known-age individuals (nfemale =8, nmale =9, nunknown =1; birth to 21years old), from a well-documented cemetery collection, Spitalfields Christ Church, London, UK, this study explores growth-related changes in cortical and trabecular bone microstructure. Micro-CT scans of mid-shaft middle thoracic ribs are used for quantitative analysis. Results are then compared topreviously quantified conventional histomorphometry of the same sample. Total area (Tt.Ar), cortical area (Ct.Ar), cortical thickness (Ct.Th), and the major (Maj.Dm) and minor (Min.Dm) diameters of the rib demonstrate positive correlations with age. Pore density (Po.Dn) increases, but age-related changes to cortical porosity (Ct.Po) appear to be non-linear. Trabecular thickness (Tb.th) and trabecular separation (Tb.Sp) increase with age, whereas trabecular bone pattern factor (Tb.Pf), structural model index (SMI), and connectivity density (Conn.D) decrease with age. Sex-based differences were not identified for any of the variables included in this study. Some samples display clear evidence of diagenetic alteration without corresponding changes in radiopacity, which compromises the reliability of bone mineral density (BMD) data in the study of past populations. Cortical porosity data are not correlated with two-dimensional measures of osteon population density (OPD). This suggests that unfilled resorption spaces contribute more significantly to cortical porosity than do the Haversian canals of secondary osteons. Continued research using complementary imaging techniques and a wide array of histological variables will increase our understanding of age- and sex-specific ontogenetic patterns within and among human populations.

Impaired Movement Scaling and Reduced Synchrony with Vestibule Closure Characterize Swallowing in Severe Dysphagia.

The contribution of hyoid and laryngeal movement deficits to penetration or aspiration in dysphagia is unclear, partly due to large variations in normal hyolaryngeal kinematics for swallowing. In healthy volunteers, laryngeal and hyoid kinematics relate to the requirements for laryngeal vestibule closure suggesting a central schematic control of movement magnitude and patterning for airway protection. Our first aim was to determine if patients with severe dysphagia showed evidence of an impaired swallowing schema, by examining if their kinematic measures were related to their hyolaryngeal space before swallow onset, and if hyolaryngeal movement synchrony for vestibule closure was disrupted. Our second aim was to determine the kinematic measures that predicted bolus penetration and aspiration in dysphagia. The methods included two-dimensional measures of the hyoid and laryngeal anterior and superior displacement and velocity, and the change in laryngeal vestibule area made from videofluoroscopic swallow recordings of 21 healthy volunteers and 21 patients with dysphagia on tube feeding secondary to the stroke or head and neck cancer. The results demonstrated that the patients did not adapt their hyolaryngeal movements during swallowing to their initial hyolaryngeal space. Further, none of the patients' measures of hyoid or laryngeal peak velocity timing were synchronized with vestibule closure, demonstrating a disorganized movement patterning. Laryngeal elevation peak velocity independently predicted penetration and aspiration. In conclusion, the central schema for swallowing patterning was disturbed, impairing the integration of kinematic actions for airway protection in severe dysphagia, while laryngeal peak elevation velocity predicted penetration and aspiration on patient swallows.

Normal basic 2D echocardiographic values to screen and follow up the athlete's heart from juniors to adults: What is known and what is missing. A critical review.

In the last few years, multiple echocardiographic nomograms have been published. However, normal values calculated in the general population are not applicable to athletes, whose hearts may be enlarged and hypercontractile. Accordingly, athletes require specific nomograms. Our aim is to provide a critical review of echocardiographic nomograms on two-dimensional (2D) measures for athletes. We performed a systematic search in the National Library of Medicine for Medical Subject Headings and free text terms including echocardiography, athletes, normal values and nomograms. The search was refined by adding the keywords heart, sport, elite, master, children and young. Twenty-eight studies were selected for the final analysis. Our research revealed that currently available ranges of normality for athletes reported by different authors are quite consistent, with limited exceptions (e.g. atria, aorta). Numerical and methodological limitations, however, emerged. Numerical limitations included a limited sample size (e.g. < 450 subjects) of the population assessed and the paucity of data in women, non-Caucasian athletes, and junior and master athletes. Some data on M-mode measurements are available, while those for some specific structures (e.g. left atrial (LA) area and volumes, right ventricular diameters and aorta) are limited or rare (e.g. LA area). There was heterogeneity in data normalization (by gender, sport type and ethnicity) and their expression was limited to mean values (Z-scores have rarely been employed), while variability analysis was often lacking or incomplete. We conclude that comprehensive nomograms using an appropriate sample size, evaluating a complete dataset of 2D (and three-dimensional) measures and built using a rigorous statistical approach are warranted.

A novel method optimizing the normalization of cardiac parameters in small animal models: the importance of dimensional indexing.

For indexing cardiac measures in small animal models, tibia length (TL) is a recommended surrogate for body weight (BW) that aims to avoid biases because of disease-induced BW changes. However, we question if indexing by TL is mathematically correct. This study aimed to investigate the relation between TL and BW, heart weight, ventricular weights, and left ventricular diameter to optimize the current common practice of indexing cardiac parameters in small animal models. In 29 healthy Wistar rats (age 5-34 wk) and 116 healthy Black 6 mice (age 3-17 wk), BW appeared to scale nonlinearly to TL1 but linearly to TL3. Formulas for indexing cardiac weights were derived. To illustrate the effects of indexing, cardiac weights between the 50% with highest BW and the 50% with lowest BW were compared. The nonindexed cardiac weights differed significantly between groups, as could be expected (P < 0.001). However, after indexing by TL1, indexed cardiac weights remained significantly different between groups (P < 0.001). With the derived formulas for indexing, indexed cardiac weights were similar between groups. In healthy rats and mice, BW and heart weights scale linearly to TL3. This indicates that not TL1 but TL3 is the optimal surrogate for BW. New formulas for indexing heart weight and isolated ventricular weights are provided, and we propose a concept in which cardiac parameters should not all be indexed to the same measure but one-dimensional measures to BW1/3 or TL1, two-dimensional measures to BW2/3 or TL2, and three-dimensional measures to BW or TL3. NEW & NOTEWORTHY In healthy rats and mice, body weight (BW) scales linearly to tibia length (TL) to the power of three (TL3). This indicates that for indexing cardiac parameters, not TL1 but TL3 is the optimal surrogate for BW. New formulas for indexing heart weight and isolated ventricular weights are provided, and we propose a concept of dimensionally consistent indexing. This concept is proposed to be widely applied in small animal experiments.

Relationship Between 2-Dimensional Frontal Plane Measures and the Knee Abduction Angle During the Drop Vertical Jump.

Context: Knee abduction angle (KAA), as measured by 3-dimensional marker-based motion capture systems during jump-landing tasks, has been correlated with an elevated risk of anterior cruciate ligament injury in females. Due to the high cost and inefficiency of KAA measurement with marker-based motion capture, surrogate 2-dimensional frontal plane measures have gained attention for injury risk screening. The knee-to-ankle separation ratio (KASR) and medial knee position (MKP) have been suggested as potential frontal plane surrogate measures to the KAA, but investigations into their relationship to the KAA during a bilateral drop vertical jump task are limited. Objective: To investigate the relationship between KASR and MKP to the KAA during initial contact of the bilateral drop vertical jump. Design: Descriptive. Setting: Biomechanics laboratory. Participants: A total of 18 healthy female participants (mean age: 24.1 [3.88]y, mass: 65.18 [10.34]kg, and height: 1.63 [0.06]m). Intervention: Participants completed 5 successful drop vertical jump trials measured by a Vicon marker-based motion capture system and 2 AMTI force plates. Main Outcome Measure: For each jump, KAA of the tibia relative to the femur was measured at initial contact along with the KASR and MKP calculated from planar joint center data. The coefficient of determination (r2) was used to examine the relationship between the KASR and MKP to KAA. Results: A strong linear relationship was observed between MKP and KAA (r2 = .71), as well as between KASR and KAA (r2 = .72). Conclusions: Two-dimensional frontal plane measures show strong relationships to the KAA during the bilateral drop vertical jump.

Change in Strain Echocardiography Predicts Mortality in Takotsubo Cardiomyopathy

IntroductionTakotsubo cardiomyopathy (TC) is an acute heart failure syndrome. Although left ventricular ejection fraction (LVEF) often improves, TC leads to significant morbidity and mortality in select patients. Two-dimensional speckle tracking strain echocardiography measures myocardial deformation, a sensitive marker for myocardial dysfunction. We sought to evaluate the utility of changes in myocardial strain to predict mortality in TC.HypothesisWe hypothesized that temporal changes in strain values will predict mortality in TC better than change in LVEF.MethodsWe retrospectively identified patients with TC based on ICD9/10 codes at a single center between 2006-2017. Two-dimensional echocardiography was used to measure LVEF and speckle tracking strain echocardiography was used to measure global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) with TomTec Arena software version 2.21. Measurements from presentation and follow-up echocardiograms were obtained. Absolute differences in values between echocardiograms was also determined. A multivariable Cox proportional hazards model evaluated association with time to all-cause mortality within 1 year.ResultsWe identified 192 patients with mean age 66.4 +/− 14.8 years, 78% women, and 62% white. Within 1 year, 33 (17%) deaths occurred. A multivariate analysis showed LVEF, GLS, GCS, and GRS at presentation were not significantly associated with time to all-cause mortality (Table 1). A subgroup analysis of 102 patients with a follow-up echocardiogram (median 16.5 days later) assessed change in LVEF and strain. There were 14 deaths (14%) in the subgroup. A multivariate analysis showed absolute change in GLS and GCS values were significantly associated with time to all-cause mortality, whereas LVEF and GRS were not (Table 2).ConclusionIn this single-center, retrospective study, LVEF and strain at presentation were not associated with mortality. However, lack of improvement in GLS and GCS was associated with increased risk of mortality. This finding demonstrates the utility of strain echocardiography in TC, as changes in strain were a better predictor of adverse outcomes than LVEF at presentation, changes in LVEF, and strain measurements at baseline. Takotsubo cardiomyopathy (TC) is an acute heart failure syndrome. Although left ventricular ejection fraction (LVEF) often improves, TC leads to significant morbidity and mortality in select patients. Two-dimensional speckle tracking strain echocardiography measures myocardial deformation, a sensitive marker for myocardial dysfunction. We sought to evaluate the utility of changes in myocardial strain to predict mortality in TC. We hypothesized that temporal changes in strain values will predict mortality in TC better than change in LVEF. We retrospectively identified patients with TC based on ICD9/10 codes at a single center between 2006-2017. Two-dimensional echocardiography was used to measure LVEF and speckle tracking strain echocardiography was used to measure global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) with TomTec Arena software version 2.21. Measurements from presentation and follow-up echocardiograms were obtained. Absolute differences in values between echocardiograms was also determined. A multivariable Cox proportional hazards model evaluated association with time to all-cause mortality within 1 year. We identified 192 patients with mean age 66.4 +/− 14.8 years, 78% women, and 62% white. Within 1 year, 33 (17%) deaths occurred. A multivariate analysis showed LVEF, GLS, GCS, and GRS at presentation were not significantly associated with time to all-cause mortality (Table 1). A subgroup analysis of 102 patients with a follow-up echocardiogram (median 16.5 days later) assessed change in LVEF and strain. There were 14 deaths (14%) in the subgroup. A multivariate analysis showed absolute change in GLS and GCS values were significantly associated with time to all-cause mortality, whereas LVEF and GRS were not (Table 2). In this single-center, retrospective study, LVEF and strain at presentation were not associated with mortality. However, lack of improvement in GLS and GCS was associated with increased risk of mortality. This finding demonstrates the utility of strain echocardiography in TC, as changes in strain were a better predictor of adverse outcomes than LVEF at presentation, changes in LVEF, and strain measurements at baseline.

Inflationary study of non-Gaussianity using two-dimensional geometrical measures of CMB temperature maps

In this work we effectively calculated the two-dimensional Minkowski functionals for cosmic microwave background (CMB) temperature maps generated by single field models of inflation with a standard kinetic term. We started with calculation of the bispectrum of initial perturbations and then calculated the two-dimensional configuration space cubic moments for temperature fluctuations. These cubic moments give rise to first order non-Gaussian correction terms to the Minkowski functionals. Thus, we developed a robust mechanism to predict the amount of non-Gaussianity generated by inflation in the CMB temperature maps using Minkowski functionals.

Efficient fog prediction with multi-objective evolutionary neural networks

This paper proposes the application of novel artificial neural networks with evolutionary training and different basic functions (sigmoidal, product and radial), for a real problem of fog events classification from meteorological input variables. Specifically, a Multiobjective Evolutionary Algorithm is considered as artificial neural network training mechanism in order to obtain a binary classification model for the detection of fog events at Valladolid airport (Spain). The evolutionary neural models developed are based on two-dimensional performance measures: traditional accuracy and the minimum sensitivity, as the lowest percentage of examples correctly predicted as belonging to each class with respect to the total number of examples in the corresponding class. These performance measures are directly related to features associated with any classifier: its global performance and the rate of the worst classified class. These two objectives are usually in conflict when the optimization process tries to construct models with a high classification rate level in the generalization dataset, and also with a good classification level for each class or minimum sensitivity. A sensitivity analysis of the proposed models is carried out, and thus the subjacent relations between the input variables and the output classification target can be better understood.

On the singular sets of solutions to the Kapustin\u2013Witten equations and the Vafa\u2013Witten ones on compact K\xe4hler surfaces

This article finds a structure of singular sets on compact Kähler surfaces, which Taubes introduced in the studies of the asymptotic analysis of solutions to the Kapustin–Witten equations and the Vafa–Witten ones originally on smooth four-manifolds. These equations can be seen as real four-dimensional analogues of the Hitchin equations on Riemann surfaces, and one of common obstacles to be overcome is a certain unboundedness of solutions to these equations, especially of the “Higgs fields”. The singular sets by Taubes describe part of the limiting behaviour of a sequence of solutions with this unboundedness property, and Taubes proved that the real two-dimensional Haussdorff measures of these singular sets are finite. In this article, we look into the singular sets, when the underlying manifold is a compact Kähler surface, and find out that they have the structure of an analytic subvariety in this case.

Three-dimensional assessment of squats and drop jumps using the Microsoft Xbox One Kinect: Reliability and validity

ABSTRACTThe Microsoft Xbox One Kinect™ (Kinect V2) contains a depth camera that can be used to manually identify anatomical landmark positions in three-dimensions independent of the standard skeletal tracking, and therefore has potential for low-cost, time-efficient three-dimensional movement analysis (3DMA). This study examined inter-session reliability and concurrent validity of the Kinect V2 for the assessment of coronal and sagittal plane kinematics for the trunk, hip and knee during single leg squats (SLS) and drop vertical jumps (DVJ). Thirty young, healthy participants (age = 23 ± 5yrs, male/female = 15/15) performed a SLS and DVJ protocol that was recorded concurrently by the Kinect V2 and 3DMA during two sessions, one week apart. The Kinect V2 demonstrated good to excellent reliability for all SLS and DVJ variables (ICC ≥ 0.73). Concurrent validity ranged from poor to excellent (ICC = 0.02 to 0.98) during the SLS task, although trunk, hip and knee flexion and two-dimensional measures of knee abduction and frontal plane projection angle all demonstrated good to excellent validity (ICC ≥ 0.80). Concurrent validity for the DVJ task was typically worse, with only two variables exceeding ICC = 0.75 (trunk and hip flexion). These findings indicate that the Kinect V2 may have potential for large-scale screening for ACL injury risk, however future prospective research is required.

Four-Dimensional Echocardiographic Automated Right Ventricular Function Assessment Demonstrates Excellent Correlation with Conventional Two-Dimensional Measures

Background: Right ventricular (RV) functional quantification has become increasingly important, particularly in patients with pulmonary hypertension. Echo-based four-dimensional (4D) automated RV quantifications (4DAutoRVQ) were compared with conventional two-dimensional RV parameters.

Can food production diversity influence farm households’ dietary diversity? An appraisal from two-dimensional food diversity measures

Purpose Emphasis on the potential roles diverse farm production systems could play in enhancing food consumption variety and nutritional well-being in rural developing countries has increased in recent times. However, there are paucities of empirical works connecting diversity in agricultural production and dietary diversity in Africa, and Nigeria in particular. The purpose of this paper is to, therefore, examine, among others, the causal link between farm production diversity and consumption of varied diets among farm households in Nigeria using a nationally representative panel data. Design/methodology/approach Unlike the simple food count measure, the authors adopt two-dimensional indices to assess food diversity, and estimated both fixed and random effects versions of panel data econometrics models with the two-dimensional indices as regressands. Findings Results show that food production system is less diverse with an average farm household consuming fairly varied foods across seasons. All the econometrics models estimated consistently established positive and statistically significant influence of farm production diversity on household dietary diversity. Higher food prices, especially rice and roots and tubers could substantially reduce dietary diversity with the negative effects likely to be more devastating for low-income farm households. The specificity of household being a net food seller had positive, although weak influence on dietary diversity. Originality/value The findings accentuate, among others, the need for strategies to promote farm production diversity, transform farm households to net-sellers of foods and enable them take advantage of food price signals to boost farm incomes as important pathway for diet quality improvement and reduction of food insecurity, malnutrition and related diseases in rural Nigeria

Investigation of microvascular morphological measures for skeletal muscle tissue oxygenation by image-based modelling in three dimensions.

The supply of oxygen in sufficient quantity is vital for the correct functioning of all organs in the human body, especially for skeletal muscle during exercise. Traditionally, microvascular oxygen supply capability is assessed by the analysis of morphological measures on transverse cross-sections of muscle, e.g. capillary density or capillary-to-fibre ratio. In this work, we investigate the relationship between microvascular structure and muscle tissue oxygenation in mice. Phase contrast imaging was performed using synchrotron radiation computed tomography (SR CT) to visualize red blood cells (RBCs) within the microvasculature in mouse soleus muscle. Image-based mathematical modelling of the oxygen diffusion from the RBCs into the muscle tissue was subsequently performed, as well as a morphometric analysis of the microvasculature. The mean tissue oxygenation was then compared with the morphological measures of the microvasculature. RBC volume fraction and spacing (mean distance of any point in tissue to the closest RBC) emerged as the best predictors for muscle tissue oxygenation, followed by length density (summed RBC length over muscle volume). The two-dimensional measures of capillary density and capillary-to-fibre ratio ranked last. We, therefore, conclude that, in order to assess the states of health of muscle tissue, it is advisable to rely on three-dimensional morphological measures rather than on the traditional two-dimensional measures.

Ecological connectivity in the three-dimensional urban green volume using waveform airborne lidar

The movements of organisms and the resultant flows of ecosystem services are strongly shaped by landscape connectivity. Studies of urban ecosystems have relied on two-dimensional (2D) measures of greenspace structure to calculate connectivity. It is now possible to explore three-dimensional (3D) connectivity in urban vegetation using waveform lidar technology that measures the full 3D structure of the canopy. Making use of this technology, here we evaluate urban greenspace 3D connectivity, taking into account the full vertical stratification of the vegetation. Using three towns in southern England, UK, all with varying greenspace structures, we describe and compare the structural and functional connectivity using both traditional 2D greenspace models and waveform lidar-generated vegetation strata (namely, grass, shrubs and trees). Measures of connectivity derived from 3D greenspace are lower than those derived from 2D models, as the latter assumes that all vertical vegetation strata are connected, which is rarely true. Fragmented landscapes that have more complex 3D vegetation showed greater functional connectivity and we found highest 2D to 3D functional connectivity biases for short dispersal capacities of organisms (6 m to 16 m). These findings are particularly pertinent in urban systems where the distribution of greenspace is critical for delivery of ecosystem services.

Semiautomatic quantification of carotid plaque volume with three-dimensional ultrasound imaging

ObjectiveVessel wall volume (VWV) assessed by three-dimensional duplex ultrasound (3DUS) imaging provides a more comprehensive measure of plaque burden than conventional two-dimensional measures of diameter stenosis. We previously demonstrated that manual outlining of the arterial lumen-intima boundary and outer wall boundary can be performed reliably on images obtained with a commercially available 3D-DUS transducer. Manual segmentation, however, is time consuming (∼45 minutes), limiting its clinical translation. We have developed a semiautomatic algorithm (manual selection of the carotid bifurcation image with subsequent automatic plaque outlining) to outline carotid plaques on 3DUS data sets. In this study, we investigated the accuracy, reproducibility, reliability, and time taken by this algorithm. Methods3DUS data sets from 30 patients with asymptomatic ≥50% carotid stenosis underwent manual outlining of lumen-intima boundary and outer wall boundary to measure VWV. Two observers implemented a semiautomatic segmentation algorithm. The algorithm's accuracy was compared with manual outlining using the Pearson correlation coefficient. The Dice similarity coefficient (DSC) and modified-Hausdorff distance (MHD) were used to quantify the geometric similarity of the outlines. We also compared results after an intermediate stage of the algorithm vs the complete algorithm. Reproducibility and the least amount of detectable change in plaque volume were computed for each method. Intraobserver and interobserver metrics for each method were computed using the intraclass correlation coefficient (ICC), coefficient of variability (CV), minimum detectable change (MDC), and standard error of measurement (SEM) of the VWV. ResultsPlaque volume estimates obtained from the semiautomatic algorithm were accurate compared with manual outlining. The Pearson correlation coefficient was 0.76 (P < .001), and measurements were geometrically similar (DSC, 0.85; MHD, 0.48 mm). The algorithm was more reproducible and reliable and could detect smaller changes in plaque volume on repeat imaging (low interobserver variability: ICC, 0.9; CV, 8.22%; MDC, 5.57%; SEM, 1.45%; DSC, 0.88; MHD, 0.43 mm). Intraobserver variability was even lower (ICC, 0.9; CV, 8%; MDC, 3.62%; SEM, 1.31%; DSC, 0.89; MHD, 0.37 mm). Plaque volume estimates at the intermediate stage of the algorithm matched results from the full algorithm (Pearson correlation coefficient, 0.76; DSC, 0.84; MHD, 0.52 mm). The intermediate approach, however, was less reliable than the full algorithm (interobserver: ICC, 0.81; CV, 11.7%; MDC, 9.58%; SEM, 3.46%; DSC, 0.88; MHD, 0.42 mm; intraobserver: ICC, 0.87; CV, 8.6%; MDC, 4.55%; SEM, 1.64%; DSC, 0.89; MHD, 0.38 mm). The full algorithm required ∼14 minutes to implement. However, a quick (7 minutes) and accurate assessment of VWV can be obtained by running only the intermediate stage of the algorithm, although with a loss in repeatability and reliability. ConclusionsWe present a unique algorithm to perform semiautomatic quantification of carotid plaque volume using 3DUS imaging. It is quick (mean time, 14 minutes), accurate, repeatable, and implementable in a clinical environment and in longitudinal studies tracking plaque progression. It reliably detects plaque volume changes as low as 4% to 6% with 95% confidence.

Assédio Moral em Estudantes Trabalhadores e sua Relação com o Bem-Estar no Trabalho

Este trabalho tem o intuito de investigar o assédio moral e as possíveis relações com o bem-estar notrabalho. Foram aplicados o Questionário Biosociodemográfico e Laboral, o Questionário de AtosNegativos - QAN e as Medidas de Bem-estar no Trabalho em 457 acadêmicos de graduação. Osresultados mostraram que há relação entre o assédio moral e as medidas de bem-estar no trabalho(p&lt;0,05), indicando que a presença da violência psicológica causa uma diminuição no bem-estar laboral.Na análise de regressão linear, alguns atos negativos no trabalho foram preditores de duas dimensões dasmedidas de bem estar no trabalho. Estes resultados sugerem que a ocorrência de assédio moral estáassociada a menor satisfação e comprometimento no trabalho.

Reference intervals and allometric scaling of two-dimensional echocardiographic measurements in 150 healthy cats.

The objective of the study was to evaluate the effects of body weight (BW), breed, and sex on two-dimensional (2D) echocardiographic measures, reference ranges, and prediction intervals using allometrically-scaled data of left atrial (LA) and left ventricular (LV) size and LV wall thickness in healthy cats. Study type was retrospective, observational, and clinical cohort. 150 healthy cats were enrolled and 2D echocardiograms analyzed. LA diameter, LV wall thickness, and LV dimension were quantified using three different imaging views. The effect of BW, breed, sex, age, and interaction (BW*sex) on echocardiographic variables was assessed using univariate and multivariate regression and linear mixed model analysis. Standard (using raw data) and allometrically scaled (Y=a × Mb) reference intervals and prediction intervals were determined. BW had a significant (P<0.05) independent effect on 2D variables whereas breed, sex, and age did not. There were clinically relevant differences between reference intervals using mean ± 2SD of raw data and mean and 95% prediction interval of allometrically-scaled variables, most prominent in larger (>6 kg) and smaller (<3 kg) cats. A clinically relevant difference between thickness of the interventricular septum (IVS) and dimension of the LV posterior wall (LVPW) was identified. In conclusion, allometric scaling and BW-based 95% prediction intervals should be preferred over conventional 2D echocardiographic reference intervals in cats, in particular in small and large cats. These results are particularly relevant to screening examinations for feline hypertrophic cardiomyopathy.