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Transcatheter implantation of pulmonary balloon-expandable stent-valves requires pre-stenting of the right ventricular outflow tract with large calibre stents. To increase awareness of the associated risks of this part of transcatheter pulmonary valve replacement therapy, we report potential fatal complications during the implantation of AndraStents® in the right ventricular outflow tract in six cases from five different European institutions and their management.
Method and result:
We present a retrospective case series analysis looking at the time period from 2013 to 2018. Of 127 AndraStents® implanted in the right ventricular outflow tract, in six patients, age from 13 to 71 years, a misconfiguration of the AndraStent® occurred forming a “diabolo”-configuration. During inflation of the balloon, the stent showed extreme “dog-boning”, an expansion of the stent at both ends with the middle part remaining unexpanded. This led to rupture of the balloon and loss of manoeuvrability in four patients. Out of the total six cases, in four patients the stent was eventually expanded with high-pressure balloons, and in one case the stent was surgically retrieved. In one patient, in whom a percutaneous retrieval of the embolised stent was attempted, a fatal bleeding occurred.
Pre-stenting of the right ventricular outflow tract by AndraStents® can lead to misconfiguration of the stent with potentially fatal complications. Rescue strategies of misconfigured stents include stent inflation and placement with high pressure non-compliant balloons or surgical backup. Interventional retrieval measures of AndraStents® cannot be advised.
This article analyses the evolution of nutritional inequality in Spain among cohorts born between 1840 and 1964. With male height data (N = 358,253), the secular trend of biological well-being and intergenerational anthropometric inequalities are studied based on the coefficient of variation, height percentiles and socioeconomic categories (students, literate non-students and illiterate). The results reveal that the nutritional inequalities were very large in the mid-19th century. Anthropometric inequalities diminished among those born between 1880 and 1919 and increased again, although only moderately, from the cohorts of the 1920s. From the 1930s there was a cycle of sustained increase in height. Despite nutritional improvement, the data suggest that nutritional inequalities increased during the Franco regime, affecting the low-income population segments particularly.
A 6–18 GHz high-power amplifier (HPA) design in GaN on SiC technology is presented. This power amplifier consists of a two-stage corporate amplifier with two and four transistors, respectively. It has been fabricated on UMS using their 0.25 µm gate length process, GH25. A study of the suitable attachment method and measurement on wafer and on jig are detailed. This HPA exhibits an averaged output power of 39.2 dBm with a mean gain of 11 dB in saturation and a 24.5% maximum power added efficiency in pulse mode operation with a duty cycle of 10% with a 25 µs pulse width.
This study examined (1) the association of dietary energy density from solid (EDS) and solid plus liquids (EDSL) with adiposity and cardiometabolic risk factors (CRF) in children with overweight and obesity, (2) the effect of under-reporting on the mentioned associations and (3) whether the association between ED and body composition and CRF is influenced by levels of physical activity. In a cross-sectional design, 208 overweight and obese children (8–12-year-old; 111 boys) completed two non-consecutive 24 h recalls. ED was calculated using two different approaches: EDS and EDSL. Under-reporters were determined with the Goldberg method. Body composition, anthropometry and fasting blood sample measurements were performed. Moderate to vigorous physical activity (MVPA) was registered with accelerometers (7-d-register). Linear regressions were performed to evaluate the association of ED with the previously mentioned variables. Neither EDS nor EDSL were associated with body composition or CRF. However, when under-reporters were excluded, EDS was positively associated with BMI (P=0·019), body fat percentage (P=0·005), abdominal fat (P=0·008) and fat mass index (P=0·018), while EDSL was positively associated with body fat percentage (P=0·008) and fat mass index (P=0·026). When stratifying the group according to physical activity recommendations, the aforementioned associations were only maintained for non-compliers. Cluster analysis showed that the low-ED and high-MVPA group presented the healthiest profile for all adiposity and CRF. These findings could partly explain inconsistencies in literature, as we found that different ED calculations entail distinct results. Physical activity levels and excluding under-reporters greatly influence the associations between ED and adiposity in children with overweight and obesity.
Preliminary evidence suggests that hoarding disorder (HD) and obsessive-compulsive disorder (OCD) may show distinct patterns of brain activation during executive performance, although results have been inconclusive regarding the specific neural correlates of their differential executive dysfunction. In the current study, we aim to evaluate differences in brain activation between patients with HD, OCD and healthy controls (HCs) during response inhibition, response switching and error processing.
We assessed 17 patients with HD, 18 patients with OCD and 19 HCs. Executive processing was assessed inside a magnetic resonance scanner by means of two variants of a cognitive control protocol (i.e. stop- and switch-signal tasks), which allowed for the assessment of the aforementioned executive domains.
OCD patients performed similar to the HCs, differing only in the number of successful go trials in the switch-signal task. However, they showed an anomalous hyperactivation of the right rostral anterior cingulate cortex during error processing in the switch-signal task. Conversely, HD patients performed worse than OCD and HC participants in both tasks, showing an impulsive-like pattern of response (i.e. shorter reaction time and more commission errors). They also exhibited hyperactivation of the right lateral orbitofrontal cortex during successful response switching and abnormal deactivation of frontal regions during error processing in both tasks.
Our results support that patients with HD and OCD present dissimilar cognitive profiles, supported by distinct neural mechanisms. Specifically, while alterations in HD resemble an impulsive pattern of response, patients with OCD present increased error processing during response conflict protocols.
The aim of the study was to determine the main factors (sociodemographic, anthropometric, lifestyle and health status) associated with high Na excretion in a representative population of Chile.
Na excretion (g/d), a valid marker of Na intake, was determined by urine analysis and Tanaka’s formulas. Blood pressure was measured by trained staff and derived from the mean of three readings recorded after 15 min rest. The associations of Na excretion with blood pressure and the primary correlates of high Na excretion were determined using logistic regression.
Chileans aged ≥15 years.
Participants (n 2913) from the Chilean National Health Survey 2009–2010.
Individuals aged 25 years or over, those who were obese and those who had hypertension, diabetes or metabolic syndrome were more likely to have higher Na excretion. The odds for hypertension increased by 10·2 % per 0·4 g/d increment in Na excretion (OR=1·10; 95 % CI 1·06, 1·14; P < 0·0001). These findings were independent of major confounding factors.
Age, sex, adiposity, sitting behaviours and existing co-morbidities such as diabetes were associated with higher Na excretion levels in the Chilean population. These findings could help policy makers to implement public health strategies tailored towards individuals who are more likely to consume high levels of dietary salt.
Composites from carbon nanotubes and polymers have been synthesized and studied. The composites were obtained joining carbon nanotubes with polymethyl methacrylate, nylon-6 and polystyrene. The materials were observed through scanning electron microscopy to evaluate the carbon nanotubes dispersion in the polymeric matrices. FTIR and Raman spectroscopies were used to analyze the interactions among functionalized and non-functionalized multiwalled carbon nanotubes and polymers, demonstrating affinity and peculiar spectra behaviors for each composite with different carbon nanotubes loads.
The work shows the preparation and characterization of composite materials using a polymer as a matrix (ABS) and carbon black or a graphenic material (graphene or graphene foam). The materials were individually mixed with the polymer and the process parameters were established in an extruder with capacity for temperature control starting at laboratory conditions and up to 600 °C. The process parameters were adjusted to form filaments that were subsequently used in a 3D printer. The parameters of the printing process were adjusted to achieve the production of flat prototypes. These prototypes were characterized by Digital Optical Microscopy. The degree of homogeneity of the prototypes and the working ranges for the graphene material concentrations were determined. Even though the characterizations were done in flat samples, 3D printing allows obtaining a great diversity of structure that broadens the diversity of applications for such kind of composite materials.
PA6 and PMMA polymers with different MWCNTs addition (5, 7 and 9 wt %) were synthetized through casting solution, resulting in improvement properties in contrast to pristine polymers. SEM images showed the MWCNTs embedded into polymeric matrices. D, G and G´ bands of MWCNTs were confirmed by Raman spectroscopy and functional groups observed in both nanocomposites by FTIR demonstrated a strong interaction. A significant increasing in electrical conductivity and microhardness was observed in all the nanocomposites. Major microhardness values were obtained in MWCNTs/PA6 (50 HV) however the MWCNTs/PMMA nanocomposites showed the highest electrical conductivity value (6.4×10-4 S/cm).
The neurocognitive trajectory in bipolar disorder (BD) is variable, with controversial findings, and most evidence come from cross-sectional studies. We aimed to examine the course of neurocognitive functioning in a sample of euthymic BD patients in comparison with a control group during a 5-year follow-up.
Ninety-nine euthymic bipolar patients and 40 healthy controls were assessed using a comprehensive neurocognitive battery (six neurocognitive domains) at baseline (T1) and then at 5-year follow-up (T2) in a longitudinal study.
No evidence of a progression in neurocognitive dysfunction was found either in cognitive composite index or in any of the neurocognitive domains for the whole cohort. However, there was a negative correlation between number of manic episodes and hospitalisations due to manic episodes and change in neurocognitive composite index (NCI) during the follow-up. Moreover, patients with higher number of manic and hypomanic episodes have a greater decrease in NCI, working memory and visual memory. History of psychotic symptoms was not related to the trajectory of neurocognitive impairment.
Our results suggest that, although the progression of cognitive decline is not a general rule in BD, BD patients who have a greater number of manic or hypomanic episodes may constitute a subgroup characterised by the progression of neurocognitive impairment. Prevention of manic and hypomanic episodes could have a positive impact on the trajectory of cognitive function.
The Padua Inventory (PI) of obsessions and compulsions is one of the most usually applied tests to assess obsessive-compulsive symptomatology in research contexts as well as for clinical and screening purposes. A reliability generalization meta-analysis was accomplished to estimate the average reliability of the PI scores and to search for characteristics of the samples and studies that can explain the variability among reliability estimates. An exhaustive literature search enabled us to select 39 studies (53 independent samples) that reported alpha and/or test-retest coefficients with the data at hand for the PI total score and subscales. An excellent average coefficient alpha was found for the PI total score (M = .935; 95%CI = .922–.949) and for Impaired Mental Control subscale (M = .911; 95%CI = .897–.924), being good for Contamination (M = .861; 95%CI = .841–.882) and Checking (M = .880; 95%CI = .856–.903), and fair for Urges and Worries (M = .783; 95%CI = .745–.822). The average test-retest reliability for PI total score was also satisfactory (M = .835; 95%CI = .782–.877). Moderator analyses showed larger coefficients alpha for larger standard deviation of the PI total scores (p = .0005; R2 = .46), for adapted versions of the test (p = .002; R2 = .32), and for samples composed of clinical participants (p = .066; R2 = .10). The practical implications of these results are discussed as well as the need for researchers to report reliability estimates with the data at hand.
This study explores variables related to teachers’ perception of disruption at school as a function of teachers (sense of personal accomplishment, professional disengagement and depersonalization and emotional exhaustion) and school (overall school management and quality of school rules) factors. Using a questionnaire regarding school climate, data from 4,055 teachers across 187 high schools were analyzed. Hierarchical linear modeling was applied and the results indicate that, taken separately, significant individual teacher predictors (Model 1) explain 26% (95% CI [.23, .29]) of the variability of the perceived disruption, especially depersonalization and emotional exhaustion. Contextual school variables (Model 2) explained 15% (95% CI [.12, .18]) of variance in teachers’ perceived disruption, with a significant negative relationship with the quality of rules. Model 3 included the above factors plus interactions between the emotional exhaustion and depersonalization variables and school indicators (30% of variance explained; 95% CI [.26, .33]). The results indicated the existence of a moderating effect for the quality of school rules, so that fair and properly-applied rules in the school context may be associated with a decrease in the relationship between depersonalization and emotional exhaustion and perceived disruption.
Research carried out in different cultural contexts shows that the use of exclusively coercive disciplinary measures does not improve the behavior of those punished, and may even increase the risks underpinning those behaviors. The aim of this research was to study whether there is a link between repeatedly suffering punishment at school and psychosocial risks in adolescence. A non-experimental design was implemented with selected groups. The participants were 507 adolescents from four groups with different risk levels: in social protection (n = 189); subject to court measures (n = 104); in treatment for drug abuse (n = 25); and comparison group (n = 189). A questionnaire was applied collectively. The variables measured were school punishments, violence, drug consumption and commission of crimes. The mild punishments variable predicted and increased the probability of consuming alcohol, tobacco and cannabis by 34% (95% CI [1.1, 1.5]), and increased the probability of using illegal drugs by 11% (95% CI [1.11, 1.30]). Te severe punishments variable increased the probability of using illegal drugs by 86% (95% CI [1.41, 2.49]) and increased the probability of committing crimes by 40% (95% CI [1.13, 1.73]). School punishments, particularly if severe, stand as a visible indicator of psychosocial risk. Behaviors subjected to punishment should alert us to the need to intervene with individuals who manifest them for which the use of exclusively coercive measures is ineffective. A wider educational intervention is required to help them find their place in school instead of excluding them from it.
Here we present a new site in the Sierra de Atapuerca (Burgos, Spain): Galería de las Estatuas (GE), which provides new information about Mousterian occupations in the Iberian Plateau. The GE was an ancient entrance to the cave system, which is currently closed and sealed by a stalagmitic crust, below which a detritic sedimentary sequence of more than 2 m is found. This has been divided into five litostratigraphic units with a rich assemblage of faunal and lithic remains of clear Mousterian affinity. Radiocarbon dates provide minimum ages and suggest occupations older than 45 14C ka BP. The palynological analysis detected a landscape change to increased tree coverage, which suggests that the sequence recorded a warming episode. The macromammal assemblage is composed of both ungulates (mainly red deer and equids) and carnivores. Taphonomic analysis reveals both anthropic, and to a lesser extent, carnivore activities. The GE was occupied by Neanderthals and also sporadically by carnivores. This new site broadens the information available regarding different human occupations at the Sierra de Atapuerca, which emphasizes the importance of this site-complex for understanding human evolution in Western Europe.
This paper considers the heating of a target in a shock wave created in a planar geometry by the ponderomotive force induced by a short laser pulse with intensity higher than 1018 W/cm2. The shock parameters were calculated using the relativistic Rankine–Hugoniot equations coupled to a laser piston model. The temperatures of the electrons and the ions were calculated as a function of time by using the energy conservation separately for ions and electrons. These equations are supplemented by the ideal gas equations of state (with one or three degrees of freedom) separately for ions and electrons. The efficiency of the transition of the work done by the laser piston into internal thermal energy is calculated in the context of the Hugoniot equations by taking into account the binary collisions during the shock wave formation from the target initial condition to the compressed domain. It is shown that for each laser intensity there is threshold pulse duration for the formation of a shock wave. The explicit calculations are done for an aluminum target.
One of the important challenges that Gaia imposes on the Astrometric Catalogs, is a careful study in everything affected by parallax. A particularly important case is the necessary linkage Gaia - HCRF - ICRF2, which require methods of analysis that are accurate enough so that the provided results are at the same precision level as the work data.
The aim of this paper is the study of the impact that the consideration of different physical properties as magnitude and spectral type of stars has on the geometric relations between Hipparcos2 and UCAC4. In this sense, the pairs of residuals Δα* and Δδ can be considered as functions of (α, δ, r) and for each fixed r, we can fit a vector field on the sphere from which to obtain its components in the VSH basis. The same can be done by grouping the stars considering their magnitudes, spectral types (or mixing them) and then studying the variations in the mentioned geometry. We must not forget that Δα* and Δδ are numerical random variables whose regression on the magnitude m, for example, can be estimated. The results will be computed taking into account r as well as the physical mentioned properties. So, we avoid the assumption that the harmonic coefficients depend only on m.
The Endangered Cuvier's gazelle Gazella cuvieri is an endemic ungulate of north-western Africa. Information on the species has been based primarily on non-systematic surveys, and the corresponding status estimates are of unknown quality. We evaluate the effectiveness and efficiency of two field methods for systematic surveys of populations of Cuvier's gazelle in arid environments: distance sampling (based on sightings) and sampling indirect sign (tracks and scats). The work was carried out in the north-western Sahara Desert, in Morocco, where what is possibly the largest population of Cuvier's gazelle persists. A logistically viable survey was conducted over a total area of c. 20.000 km2 in 10 expeditions during 2011–2014. A total of 67 sites were surveyed, with 194 walking surveys (2,169 km in total). Gazelle signs were detected at 50 sites, and gazelles were sighted at 21 sites (61 individuals). We found a relationship between sightings and abundance indices based on indirect sign, which could be useful for population monitoring or ecological studies. Additionally, the data could be used in occupancy modelling. Density estimates based on distance sampling required considerable effort; however, it is possible to survey large areas during relatively short campaigns, and this proved to be the most useful approach to obtain data on the demographic structure of the population.
This work shows the development of several models for chain-growth polymerizations that admit the direct calculation of the complete molecular weight distribution of the polymer. The direct and complete calculation implies that no statistical mean values are employed as in the moments method neither numerical approximations like in the minimum-squared based methods. The free radical polymerization of ethylene (LDPE) and the coordination via metallocenes polymerization of ethylene (HDPE) are taken as examples for analysis.
In the free radical polymerization case, the conventional scheme for chain-growth polymerization is adopted, with steps for initiation, propagation, chain transfer to small species and the additional step of chain transfer to dead chains . The kinetic parameter are obtained from the open literature. Two kind of reactors were modelled: batch and continuous stirred tank reactor. For this last case, a simulation strategy was considered in which the run started from an initial known population of dead chains. Results show that typical non-linear polymerization profiles for the molecular weight distribution are obtained. For the coordination polymerization of ethylene via metalocenes, the standard coordination model was employed . A two-site catalyst was considered and kinetic parameters reported in the open literature were used. For this study an experimental program in a lab-scale reactor was undertaken in order to obtain modelling data . Results show that the standard model adequately reproduces the experimental data in the kinetic and molecular attributes of the polymer.