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The role of right ventricular longitudinal strain for assessing patients with repaired tetralogy of Fallot is not fully understood. In this study, we aimed to evaluate its relation with other structural and functional parameters in these patients.
Patients followed-up in a grown-up CHD unit, assessed by transthoracic echocardiography, cardiac MRI, and treadmill exercise testing, were retrospectively evaluated. Right ventricular size and function and pulmonary regurgitation severity were assessed by echocardiography and MRI. Right ventricular longitudinal strain was evaluated in the four-chamber view using the standard semiautomatic method.
In total, 42 patients were included (61% male, 32±8 years). The mean right ventricular longitudinal strain was −16.2±3.7%, and the right ventricular ejection fraction, measured by MRI, was 42.9±7.2%. Longitudinal strain showed linear correlation with tricuspid annular systolic excursion (r=−0.40) and right ventricular ejection fraction (r=−0.45) (all p<0.05), which in turn showed linear correlation with right ventricular fractional area change (r=0.50), pulmonary regurgitation colour length (r=0.35), right ventricular end-systolic volume (r=−0.60), and left ventricular ejection fraction (r=0.36) (all p<0.05). Longitudinal strain (β=−0.72, 95% confidence interval −1.41, −0.15) and left ventricular ejection fraction (β=0.39, 95% confidence interval 0.11, 0.67) were independently associated with right ventricular ejection fraction. The best threshold of longitudinal strain for predicting a right ventricular ejection fraction of <40% was −17.0%.
Right ventricular longitudinal strain is a powerful method for evaluating patients with tetralogy of Fallot. It correlated with echocardiographic right ventricular function parameters and was independently associated with right ventricular ejection fraction derived by MRI.
Archaeological materials present unique records on natural processes allowing the study of long-term material behaviors such as structural modifications and degradation mechanisms. The present work is focused on the chemical and microstructural characterization of four prehistoric arsenical copper artifacts. These artifacts were characterized by micro-energy dispersive X-ray fluorescence spectrometry, optical microscopy, scanning electron microscopy with X-ray microanalysis, micro-X-ray diffraction and synchrotron radiation micro-X-ray diffraction. Cu3As is the expected intermetallic arsenide in arsenical copper alloys, reported in the literature as exhibiting a hexagonal crystallographic structure. However, a cubic Cu3As phase was identified by X-ray diffraction in all of our analyzed archaeological artifacts, while the hexagonal Cu3As phase was clearly identified only in the artifact with higher arsenic content. Occurrence of the cubic arsenide in these particular objects, suggests that it was precipitated due to long-term aging at room temperature, which points to the need of a redefinition of the Cu-As equilibrium phase constitution. These results highlight the importance of understanding the impact of structural aging for the assessment of original properties of archaeological arsenical copper artifacts, such as hardness or color.
The objective of this work was to estimate genetic parameters for a measure of persistency of milk yield and to evaluate its association with 305-d cumulative milk yield and lactation length. 12 346 records from 8202 dairy Gyr cows including lactations up to fifth calving were used. The measure of persistency was obtained from one of the parameters of a quadratic model that describes the cumulative yield across lactation as a function of days in milk. A three-trait multivariate analysis was done. Heritability and repeatability for persistency were 0·08 and 0·21, respectively. Deviance Information Criterion provided evidence that the additive genetic covariance between the measure of persistency studied and 305-d cumulative yield is zero. Genetic correlations between persistency and lactation length were 0·50 and 0·27 for first or all lactations, respectively. Milk yield persistency as measured in this study has low heritability. Selection for persistency can increase lactation length. The measure of milk yield persistency studied here is genetically independent of total milk yield and can be included in routine genetic evaluations of dairy cattle.
The estimation of age and growth of cephalopod stocks is a key issue for their sustainable management. Recently, several studies have successfully validated the daily deposition of growth rings in the vestigial shell or stylets of several octopus species. Octopus vulgaris eggs were incubated at two different temperatures, 18 and 22°C, until hatching to determine stylet size at hatching and assess the effect of temperature in the stylet dimensions. The 3-day-old hatchlings were sectioned transversally and 6 μm sections were stained to enhance the stylet position and visibility. The sections were observed under transmitted light microscopy at a magnification of 1000×, and the stylets identified as blue/green structures inside the mantle–funnel retractor muscle. The transversal sections of the whole paralarvae allowed the diameter of the embryonic stylet of an octopus species to be measured for the first time. The mean stylet diameter in 3-day-old paralarvae is 3.99 μm independently of the thermal conditions. Moreover, significant differences in stylet size between captive and wild paralarvae were observed; the latter showed significantly larger stylets, an indication that they are over 3 days old. Our results also indicate that the stylet nucleus is much smaller than previously thought based on measurements in stylets of juveniles and adults.
The application of the sterile insect technique to fruit flies involves the mass-production of the pest insects using an artificial diet, irradiation during a narrow time window at the late pupal or early imaginal stage to inhibit reproduction without affecting reproductive capacity, and then release into the target area where the sterile insects compete reproductively with their wild counterparts. The timing of irradiation is important to enable the release of males that are sterile but of good quality and exhibit an acceptable sexual performance. In this study, we examined the pupal development of 12 tephritid (Diptera: Tephritidae) species: Anastrepha fraterculus (Wiedemann), A. ludens (Loew), A. obliqua (Macquart), A. serpentina (Wiedemann), Bactrocera cucurbitae (Coquillett), B. dorsalis (Hendel), B. invadens (Drew, Tsuruta & White), B. oleae (Rossi), B. philippinensis (Drew & Hancock), B. tryoni (Froggatt), B. zonata (Saunders) and Ceratitis capitata (Wiedemann). The insects were reared at various temperatures, in the laboratory (15–28 °C) and under fluctuating natural conditions (20–35 °C). The gradual colour changes of the insect eyes during metamorphosis were observed and photographed, measuring the specific eye colour parameters of each species and matching them with the colour scale of the Munsell Soil Color Charts. The duration of pupal development and the time to emergence in Anastrepha species were longer than those in C. capitata and Bactrocera species at all the holding temperatures. The data obtained can be used by mass-rearing facilities to manage pupal holding conditions and as indicators for optimizing the timing of irradiation.
We have obtained optical integral field spectroscopy of the explosion sites of more than 25 nearby type-IIP/IIL/Ib/Ic supernovae using UH88/SNIFS, and additionally Gemini/GMOS IFU. This technique enables us to obtain both spatial and spectral information of the immediate environment of the supernovae. Using strong line method we measured the metallicity of the star cluster present at the explosion site, presumably the coeval parent stellar population of the supernova progenitor, and comparison with simple stellar population models gives age estimate of the cluster. With this method we were able to put constraints on the metallicity and age of the progenitor star. The age, i.e. lifetime, of the progenitor corresponds to the initial mass of the star. By far this is the most direct measurement of supernova progenitor metallicity and, if the cluster-progenitor association is confirmed, provides reliable determination of the initial mass of supernova progenitor stars.
In this work Spectroscopic Ellipsometry (SE) was used to study metal induced crystallization (MIC) on amorphous silicon films in order to analyze the influence of different annealing conditions on their structural properties. The variation of the metal thickness has shown to be determinant on the time needed to full crystallize silicon films. Films of 100 nm thickness crystallize after 2h at 500°C using 1 nm of Ni deposited on it. When reducing the average metal thickness down to 0.05 nm the same silicon film will need almost 10 hours to be totally crystallized. Using a new approach on the modelling procedure of the SE data we show to be possible to determine the Ni remaining inside the crystallized films. The method consists in using Ni as reference on the Bruggeman Effective Medium Approximation (BEMA) layer that will simulated the optical response of the crystallized silicon. Silicon samples and metal layers with different thicknesses were analyzed and this new method has shown to be sensible to changes on the initial metal/silicon ratio. The nickel distribution inside the silicon layers was independently measured by Rutherford Backscattering Spectroscopy (RBS) to check the data obtained from the proposed approach.
To evaluate the effectiveness of a positive deviance strategy for the improvement of hand hygiene compliance in 2 adult step-down units.
A 9-month, controlled trial comparing the effect of positive deviance on compliance with hand hygiene.
Two 20-bed step-down units at a tertiary care private hospital.
The first phase of our study was a 3-month baseline period (from April to June 2008) in which hand hygiene episodes were counted by use of electronic handwashing counters. From July to September 2008 (ie, the second phase), a positive deviance strategy was implemented in the east unit; the west unit was the control unit. During the period from October to December 2008 (ie, the third phase), positive deviance was applied in both units.
During the first phase, there was no statistically significant difference between the 2 step-down units in the number of episodes of hand hygiene per 1,000 patient-days or in the incidence density of healthcare-associated infections (HAIs) per 1,000 patient-days. During the second phase, there were 62,000 hand hygiene episodes per 1,000 patient-days in the east unit and 33,570 hand hygiene episodes per 1,000 patient-days in the west unit (P < .01). The incidence density of HAIs per 1,000 patient-days was 6.5 in the east unit and 12.7 in the west unit (P = .04). During the third phase, there was no statistically significant difference in hand hygiene episodes per 1,000 patient-days (P = .16) or in incidence density of HAIs per 1,000 patient-days.
A positive deviance strategy yielded a significant improvement in hand hygiene, which was associated with a decrease in the overall incidence of HAIs.
The forkbeard Phycis phycis is one of the main target species of the demersal fishery in the Azores, north-eastern Atlantic. Age and growth of the forkbeard were studied using 477 otoliths from individuals caught between April 2000 and August 2004. Otoliths were burned and sectioned, a preparation method that improved the easiness of readings. Individuals ranged from 21 to 71 cm in total length, and their estimated ages between 2 and 18 years old. Forkbeard is a relatively slow growing, long lived species, that does not show sexual dimorphism in growth. The von Bertalanffy growth parameters estimated for the Azorean forkbeard were L∞ = 79.64 cm, k = 0.09 yr−1 and t0 = −1.88 years.
The aim of the present study was to provide the first analysis of depth distribution and reproductive biology in the deep-sea cirrate octopus Opisthoteuthis calypso along the Portuguese continental slope. We used 77 specimens obtained in 7 research cruises between 1996 and 2003. Catch rates and biomass, weights, lengths, sex and maturity stages, and a morphometric description of the beak are detailed. Specimens have been collected from 553 to 960 m depth, south of 39°N, in approximately 1:1 sex-ratio. Females are larger (80:75 mm mantle length) and heavier (622:346 g total body weight) than males and both sexes have been caught in all stages of maturity in equal proportions.
Domoic acid (DA), the toxin responsible for the illness known as amnesic
shellfish poisoning (ASP), is an algal toxin produced naturally by some
species of the diatom genus Pseudo-nitzschia. The toxin has been detected in a diverse array
of marine organisms from copepods to whales. Cephalopods, which are
important members of the food chain and active predators of known toxin
vectors such as bivalves, crabs and some fishes, have just recently been
implicated in DA transfer or accumulation. Here we present data showing
detectable values of DA determined by HPLC-UV (high-performance liquid
chromatography and ultraviolet detection) and confirmed by HPLC-MS (mass
spectrometric detection) in two octopus species collected along the
Portuguese continental coast: Eledone cirrhosa and E. moschata. Domoic acid was frequently detected in
the digestive gland of E. moschata and occasionally reached concentrations exceeding
100 µg g−1. In contrast, E. cirrhosa contained lower concentrations of DA on
the few occasions that it was detected. This suggests that E. moschata is a potential
vector for DA transfer to higher trophic levels in the coastal marine food
web, not excluding humans. These data, combined with known aspects of the
life history of the species, are a necessary step towards achieving an
understanding of the accumulation of phycotoxins in cephalopods.
The first occurrence of a giant squid Architeuthis sp. specimen in Portuguese waters is noted and another reference set of biological and biometrical data provided which may in future be used in conjunction with others to further elucidate important aspects of the identity, biology and ecology of the species. The fact that the specimen is a male is relevant, since males have been much less frequent in the reports in the scientific literature than have females. Additionally, this is the most southerly report of a male known to have occurred in the Atlantic Ocean.