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To assess the validity of self-reported height and weight by parents of 4-year-old children and subjective weight perception.
Descriptive cross-sectional study.
Paediatric population living in the Autonomous Community of Madrid.
Children born in 2008–2009 examined at 47–59 months of age. Data were collected by paediatricians of the Madrid Primary Care Physicians Sentinel Network. Parents reported weight and height data. Prevalence of weight status categories was calculated using WHO and International Obesity Task Force (IOTF) reference criteria. Sensitivity, specificity and positive predictive value (PPV) were estimated. The appraisal of their child’s weight perception and parental misperception were assessed.
For 2914 children, reported height was underestimated by −1·38 cm, weight by −0·25 kg and BMI was overestimated by +0·41 kg/m2 on average. The prevalence of obesity estimated with reported data was 2·7 times higher than that calculated with measured data (16·2 v. 6·0 %) according to WHO classification, and 3·6 times higher with IOTF classification. Sensitivity to identify obesity was 70·5 %, specificity was 87·3 % and PPV was 26·2 % (WHO classification). Half of the parents of pre-schoolers with obesity failed to identify their child’s weight status. Parental misperception among children classified as having overweight or obesity reached 93·0 and 58·8 %, respectively.
Parents underestimated children’s height and weight, leading to an overestimation of the prevalence of obesity. Small inaccuracies in reported measures have an important effect for the estimation of population prevalences. Parents’ report of child weight status is unreliable. Parental awareness and acknowledgement of child weight status should be improved.
First-degree relatives of patients with psychotic disorder have higher levels of polygenic risk (PRS) for schizophrenia and higher levels of intermediate phenotypes.
We conducted, using two different samples for discovery (n = 336 controls and 649 siblings of patients with psychotic disorder) and replication (n = 1208 controls and 1106 siblings), an analysis of association between PRS on the one hand and psychopathological and cognitive intermediate phenotypes of schizophrenia on the other in a sample at average genetic risk (healthy controls) and a sample at higher than average risk (healthy siblings of patients). Two subthreshold psychosis phenotypes, as well as a standardised measure of cognitive ability, based on a short version of the WAIS-III short form, were used. In addition, a measure of jumping to conclusion bias (replication sample only) was tested for association with PRS.
In both discovery and replication sample, evidence for an association between PRS and subthreshold psychosis phenotypes was observed in the relatives of patients, whereas in the controls no association was observed. Jumping to conclusion bias was similarly only associated with PRS in the sibling group. Cognitive ability was weakly negatively and non-significantly associated with PRS in both the sibling and the control group.
The degree of endophenotypic expression of schizophrenia polygenic risk depends on having a sibling with psychotic disorder, suggestive of underlying gene–environment interaction. Cognitive biases may better index genetic risk of disorder than traditional measures of neurocognition, which instead may reflect the population distribution of cognitive ability impacting the prognosis of psychotic disorder.
Polymer additives can substantially reduce the drag of turbulent flows and the upper limit, the so-called state of ‘maximum drag reduction’ (MDR), is to a good approximation independent of the type of polymer and solvent used. Until recently, the consensus was that, in this limit, flows are in a marginal state where only a minimal level of turbulence activity persists. Observations in direct numerical simulations at low Reynolds numbers (
) using minimal sized channels appeared to support this view and reported long ‘hibernation’ periods where turbulence is marginalized. In simulations of pipe flow at
near transition we find that, indeed, with increasing Weissenberg number (
), turbulence expresses long periods of hibernation if the domain size is small. However, with increasing pipe length, the temporal hibernation continuously alters to spatio-temporal intermittency and here the flow consists of turbulent puffs surrounded by laminar flow. Moreover, upon an increase in
, the flow fully relaminarizes, in agreement with recent experiments. At even larger
, a different instability is encountered causing a drag increase towards MDR. Our findings hence link earlier minimal flow unit simulations with recent experiments and confirm that the addition of polymers initially suppresses Newtonian turbulence and leads to a reverse transition. The MDR state on the other hand results at these low
from a separate instability and the underlying dynamics corresponds to the recently proposed state of elasto-inertial turbulence.
The authors prepared a micro-structured, thermosensitive hydrogel with N-isopropylacrylamide microgels with a lower critical solution temperature (LCST) of 32 °C dispersed on a matrix of N-isopropylacrylamide-co-dimethylacrylamide with an LCST at 40 °C. Incubation of the hydrogel at 33 °C in a solution of fluorescein-albumin induced loading of the protein. The protein was not loaded at a temperature below the LCST of the microgels (4 °C), suggesting that the shrinkage of the microgels followed by the formation of micropores within the hydrogel matrix is a prerequisite for protein loading. A sustained and complete release of the loaded protein was obtained at 37 °C.
Cognitive-behavioural therapy (CBT) is an effective treatment for depressed adults. CBT interventions are complex, as they include multiple content components and can be delivered in different ways. We compared the effectiveness of different types of therapy, different components and combinations of components and aspects of delivery used in CBT interventions for adult depression. We conducted a systematic review of randomised controlled trials in adults with a primary diagnosis of depression, which included a CBT intervention. Outcomes were pooled using a component-level network meta-analysis. Our primary analysis classified interventions according to the type of therapy and delivery mode. We also fitted more advanced models to examine the effectiveness of each content component or combination of components. We included 91 studies and found strong evidence that CBT interventions yielded a larger short-term decrease in depression scores compared to treatment-as-usual, with a standardised difference in mean change of −1.11 (95% credible interval −1.62 to −0.60) for face-to-face CBT, −1.06 (−2.05 to −0.08) for hybrid CBT, and −0.59 (−1.20 to 0.02) for multimedia CBT, whereas wait list control showed a detrimental effect of 0.72 (0.09 to 1.35). We found no evidence of specific effects of any content components or combinations of components. Technology is increasingly used in the context of CBT interventions for depression. Multimedia and hybrid CBT might be as effective as face-to-face CBT, although results need to be interpreted cautiously. The effectiveness of specific combinations of content components and delivery formats remain unclear. Wait list controls should be avoided if possible.
A fundamental understanding of the filament thinning of viscoelastic fluids is important in practical applications such as spraying and printing of complex materials. Here, we present direct numerical simulations of the two-phase axisymmetric momentum equations using the volume-of-fluid technique for interface tracking and the log-conformation transformation to solve the viscoelastic constitutive equation. The numerical results for the filament thinning are in excellent agreement with the theoretical description developed with a slender body approximation. We show that the off-diagonal stress component of the polymeric stress tensor is important and should not be neglected when investigating the later stages of filament thinning. This demonstrates that such numerical methods can be used to study details not captured by the one-dimensional slender body approximation, and pave the way for numerical studies of viscoelastic fluid flows.
Cognitive deficits are a core feature of early stages in schizophrenia. However, the extent to which antipsychotic (AP) have a deleterious effect on cognitive performance remains under debate. We aim to investigate whether anticholinergic loadings and dose of AP drugs in first episode of psychosis (FEP) in advanced phase of remission are associated with cognitive impairment and the differences between premorbid intellectual quotient (IQ) subgroups.
Two hundred and sixty-six patients participated. The primary outcomes were cognitive dimensions, dopaminergic/anticholinergic load of AP [in chlorpromazine equivalents (Eq-CPZ) and the Anticholinergic Risk Scale (ARS), respectively].
Impairments in processing speed, verbal memory and global cognition were significantly associated with high Eq-CPZ and verbal impairment with high ARS score. Moreover, this effect was higher in the low IQ subgroup.
Clinicians should be aware of the potential cognitive impairment associated with AP in advanced remission FEP, particularly in lower premorbid IQ patients.
The Spanish National Network (REDETS) is a group of eight agencies, units and services, depending on National and Regional Governments that coordinate their work within a common methodological framework, guided by the principles of mutual recognition and cooperation. The necessity of considering a Quality Management System has been detected and, consequently, a common tool for all the members needs to be developed. We describe in this study the process to achieve that goal.
Based on both a review of previous literature and the proposal for a self-evaluating tool, a group of experts from each agency through consensus have developed a tool for self-evaluation in Health Technology Assessment (HTA) agencies. Through the structure described in the handbook of the Andalusian Agency for Healthcare Quality (ACSA), each standard should have a statement or proposal that needs to also include evidence or good practices, and the corresponding evaluation questions. In separate workgroups, the definition of these proposals, evidence and evaluation questions were developed. One face-to-face meeting and two meetings via teleconference were necessary to achieve a final document with all the quality standards.
From a proposed structure of sixty-six standards, the titles, definitions, statements and evidence as well as good practices and evaluation questions were established in workgroups with consensus among all of the members (1 - 3). The final version of the self-assessment tool was composed of sixty-eight standards, grouped in twelve quality criteria structured in four dimensions: I Responsibility, II Clients and Stakeholders, III Production Process, and IV Resources.
Quality management requires an evaluation tool and this version, based on a systematic review and consensus, is a useful and practical instrument for developing a handbook by each member of REDETS. An online version of the tool is in process of development.
This article presents archaeological information on the remains of five domestic dogs (Canis lupus familiaris) recovered from prehistoric sites in the lowlands of southeast Uruguay. The presence of canines in the archaeological record is associated with horticultural hunter-gatherer groups, who adapted to the changing conditions of flood-prone ecosystems during the late Holocene (ca. 3000 years BP). Three of the five specimens discussed were recovered from human burial mounds, prompting further discussion on the economic, social, and symbolic and ritual significance of these animals.
The origins of the large Classic and Postclassic urban centres of Central Mexico remain poorly understood. Archaeological investigations at the Formative site of Tlalancaleca in Puebla (Mexico) provide the first detailed study of a large-scale urban centre of that period. Preliminary results suggest that the growth and development of this particular site may have influenced the subsequent growth of Teotihuacan itself. This study explores how urbanisation can be identified archaeologically by tracing the expansion of population and the emergence of monumental architecture.
Most flows in nature and engineering are turbulent because of their large velocities and spatial scales. Laboratory experiments on rotating quasi-Keplerian flows, for which the angular velocity decreases radially but the angular momentum increases, are however laminar at Reynolds numbers exceeding one million. This is in apparent contradiction to direct numerical simulations showing that in these experiments turbulence transition is triggered by the axial boundaries. We here show numerically that as the Reynolds number increases, turbulence becomes progressively confined to the boundary layers and the flow in the bulk fully relaminarizes. Our findings support that turbulence is unlikely to occur in isothermal constant-density quasi-Keplerian flows.
Corrosion is a worldwide, crucial problem that strongly affects natural and industrial environments, in particular the oil and gas industry. Natural gas (NG) is a source of energy in industrial, residential, commercial and electric applications. The abundance of NG in many countries augurs a profitable situation for the vast energy industry. NG is considered friendlier to the environment and with lesser greenhouse gas emissions as compared with other fossil fuels. In the last years, shale gas is increasingly exploited in U.S. and Europe, applying a hydraulic fracturing technique, for releasing gas from the bed rock by injection of saline water, acidic chemicals and sand to the wells. Various critical sectors of the NG industry infrastructure suffer from several types of corrosion: steel casings of production wells and their drilling equipment; gas conveying pipelines including pumps and valves; plants for regasification of liquefied natural gas (LNG) and municipal networks of NG distribution to the consumers. Practical technologies that minimize or prevent corrosion include selection of corrosion resistant engineering materials, cathodic protection, corrosion inhibitors, and application of external and internal paints, coatings and linings. Mexico is undergoing an intense reform process of the energy sector, that involves its oil, NG and electricity industries. Typical cases of corrosion management in the NG industry are presented based on the authors experience and knowledge.
Commercial aluminum alloys corresponding to Al-Cu-Si family are commonly used in casting and molding process because their high castability. The main characteristics of these alloys are the excellent weight/strength relation in conjunction with wear and corrosion resistance. Additionally, the mechanical properties of these alloys could be enhanced by heat treatment.
In Al A319 alloys, Cu and Mg are the main responsible to increase the mechanical properties after T6 heat treatment due to the precipitation of Al2Cu and Mg2Si and Al2CuMg phase . Combined effects of Ni and Cu improve strength and hardness at relatively elevated temperature , Due to the low solubility of Ni in Al (0.04%), it has been reported the formation of FeAl9FeNi-type intermetallic, which is not totally dissolved with the typical solution treatments used in aluminum alloys . Hayajneh et al., found that increasing amounts of intermetallic compounds Al3Ni, Al3(CuNi)2 and Al7Cu4Ni in Al-Cu alloy, the hardness increase .
The effect of Ni addition and solution treatment time on the microstructure and hardness of the Al A319 alloy are studied by Vickers microhardness (VHN), Rockwell B hardness (HRB), X Ray Diffraction (XRD), Optical Microscopy (OM), Scanning Electron Microscopy (SEM).
The main purpose of this research was to establish the effectiveness of the V844 corrosion inhibitor for seawater on various metallic materials: carbon steel, aluminum and copper alloy at different concentrations via colloid formation. The changes in both physical and chemical properties of seawater, including pH, total hardness, alkalinity, total dissolved solids (TDS) and conductivity at different concentrations of V844 were assessed, too. The test procedure involves dissolving the V844 corrosion inhibitor powder provided by Magna International Private Limited in seawater to obtain a stock solution of 4% V844 in seawater, which was further diluted to obtain the remaining concentrations. The analysis of parameters begun when various metal species, polished beforehand, were placed into the solutions. The analysis was observed over a period of 26 days and a total of 9 sets of readings were obtained. From our observation and analysis, it was concluded that the inhibitor worked best at 0.05% concentration for carbon steel.
The aim of this work was to assess the corrosion and degradation effects of a biofuel on metallic materials tested in an experimental internal combustion engine (ICE). Biodiesel is considered as an alternative fuel for diesel, for industrial applications ranging from boilers to ICE. The experimental vehicle motor, fitted with carbon steel, stainless steel, aluminum alloys and magnesium alloys was operated with local biodiesel. The corrosion performance was evaluated by gravimetric, chemical and electrochemical techniques, following the practices recommended in ASTM and NACE standards for corrosion testing. This work is the result of an international cooperation between the Institute of Engineering, Autonomous University of Baja California, Mexico and the Corrosion Research Center, Sami Shamoon College of Engineering, Israel. The characteristics and conditions of the ICE operated with biodiesel, and the results of the corrosion essays are presented, analyzed and discussed.
Concrete is a composite material, composed of cement, sand, gravel and water, reinforced with steel bars or mesh. It is used for the construction of infrastructure assets such as airports, dams, ports, bridges and road ways. Polymer concrete is a relative new material containing a thermosetting resin (instead of water) displaying improved mechanical strength, low permeability, greater corrosion resistance and higher durability. It is employed for new construction and old concrete reparation in the chemical, food, fertilizer, mine and civil industries. Polymer concrete pipe specimens, reinforced with glass-fibers were prepared and exposed in a salt spray (fog) chamber, operating with a NaCl solution, following ASTM standard B-117-11. The deterioration effects were assessed by testing the physical and mechanical properties, before and after the exposure in the spray chamber, in accordance with standard ASTM D3039-2013. Corrosion resistance was evaluated applying ASTM standard C876-2013. The result of this work are presented, illustrated and discussed.
The combat fields of modern wars, including the struggle against global terrorism, are localized in diverse, harsh regions: tropical, desert, artic, marine, with varied weather conditions, which adversely affect the corrosion performance of the equipment and facilities involved.
For the sake of brevity, three groups of military mobile and fixed equipment and structures are dealt with: armored ground wheeled vehicles; naval aluminum vessels, and buildings and facilities for providing dwellings, weapons storage and services to the armed forces. They are usually made from carbon steel, aluminum alloys and reinforced concrete, because of their useful properties: high strength, easy availability and low cost. However, due to their limited corrosion resistance they should be protected by coatings (including military coatings), but primarily paint; cathodic protection and corrosion inhibitors.
All these systems suffer from several types of localized corrosion and degradation: galvanic, pitting, intergranular, dealloying, cavitation, erosion, stress cracking, UV effects in plastics and organic coatings. The military assets require the implementation of corrosion control methods and techniques through all their stages: design, construction, installation and operation. Typical cases of corrosion will be presented based on the authors experience and knowledge.
Two machines: The human body and the vehicle motor are made of structural and functional, natural and man-produced materials. They generate energy by chemical oxidation of two fluids: ethanol and gasoline. The characteristics of these fluids: a nutritive beverage and a fuel, providing motion to the vehicle, are described. The damage due to diseases in the body by excessive ethanol consumption and deterioration of the motor by corrosion are treated by means of preventive and curative methods: body rehabilitation and car repair, maintaining both machines in permanent, healthy, working operation. The chemical reactions of ethanol oxidation and gasoline combustion and their effects on the machines and their materials are presented, illustrated and discussed.
The optical and structural properties of co-doped HfO2 thin films with rare earth trivalent ions prepared by ultrasonic spray pyrolysis technique, are reported. An arrangement of multi-layer (Si-SiO2-HfO2:Eu3+-HfO2:Tb3+-HfO2:Tm3+-SiO2) were deposited on silicon substrates at temperatures from 400 to 550°C, using acetyl acetonates as precursory reagents. A refractive index value of 2.1 was determined by spectral ellipsometry. The surface morphology was obtained by AFM measurements. For 50 to 550 nm thickness films, an average roughness value of ∼56.8 Å was obtained for different substrate temperatures and grown deposition times. EDS measurements showed the presence of hafnium, and rare earths dopants as elemental composition. XPS measurements demonstrated that hafnium and rare earths oxidation species are formed at hafnium dioxide thin films. Photoluminescence emission spectra of multi-layer structures present characteristic emission peaks associated with Tb+3, Eu3+, and Tm3+ dopants. The results presented above motivate us to consider that these multilayer structures could be appropriate to be used as a rare earth host to improve optical emission.
Aluminum titanium oxynitride (TiAlNO) coatings were deposited on 316 steel substrates by the sputtering technique, varying the nitrogen flow from 2.5, 5, 7.5 to 10 sccm, and maintaining constant at 12 sccm the flow argon gas. We used targets of titanium and alumina with 99.995% purity. The hardness and tribological analyses were determined by Vickers microhardness and tribology (tribometer pin-disc), respectively. The results show that the coating with a nitrogen flow of 10 sccm had the lowest volumetric wear (2.047738693 mm3) and the maximum value of hardness (11.2 GPa). Analysis of X-ray diffraction evidenced the presence of three crystalline phases: Ti2N, Al2O3 and TiO2. It can be observed that by increasing the nitrogen flow, the portion of semi-Ti2N phase increases, Al2O3 decreases and TiO2 remains almost constant, and also producing a change in crystallographic orientation with reference to the Ti2N phase. Crystal grain sizes were estimated by X-ray diffraction Fourier line profile analysis using Warren–Averbach method. This analysis showed a grain size between 5 and 15 nm. Raman spectroscopy results show the presence of the TiO2 phase which corroborated the X-ray diffraction results.