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The slat represents an important airframe noise source as it extends over almost the entire aircraft wingspan. Most studies of slat noise consider idealized geometries. However, for practical applications, several elements are installed on its cove, such as bulb seals to avoid direct contact with the main wing surface. Previous investigations of an unswept and untapered MD30P30N airfoil reported that the flow dynamics and the corresponding acoustic noise are very sensitive to the presence and location of the bulb seal. For certain locations a second recirculation bubble is created inside the slat cove and the acoustic narrowband peaks are intensified. The present paper shows that the two-bubble topology promotes the recirculation of turbulence within the slat cove. Spectral proper orthogonal decomposition analysis based on the radiated pressure intensity is used to identify the flow structures responsible for sound generation. Even though the recirculating turbulence is mostly incoherent, it interacts with the coherent Kelvin–Helmholtz vortices in the initial part of the mixing layer. Then, vortex merging and straining lead to the formation of complex vortex clusters. Our results show that the origin and evolution of these clusters are consistent with Rossiter's mechanism responsible for the narrowband peaks. The enhanced recirculation accelerates the cluster evolution leading to wider clusters and lower-frequency Rossiter modes.
Understanding place-based contributors to health requires geographically and culturally diverse study populations, but sharing location data is a significant challenge to multisite studies. Here, we describe a standardized and reproducible method to perform geospatial analyses for multisite studies. Using census tract-level information, we created software for geocoding and geospatial data linkage that was distributed to a consortium of birth cohorts located throughout the USA. Individual sites performed geospatial linkages and returned tract-level information for 8810 children to a central site for analyses. Our generalizable approach demonstrates the feasibility of geospatial analyses across study sites to promote collaborative translational research.
To examine children’s exposure to food and beverage advertising across a year of Colombian television based on whether products exceed Pan-American Health Organization (PAHO)-defined nutrient thresholds.
Nutritional information was obtained for all foods and beverages advertised and used to categorise each product according to the product category (e.g. beverage, snack food) and nutritional quality based on the PAHO model for identifying products in excess of free sugars, Na or saturated fat or containing non-caloric sweeteners or trans-fat. Television audience ratings data were used to derive the average child audience (unique child viewers) per ad and the number of times ads were seen by children in a single week (weekly impressions) based on product category and nutritional quality.
All food and beverage ads on cable and over-the-air TV in Colombia in 2017.
Of all instances of TV ads, 89·3 % were of unhealthy products. A larger proportion of male and female children, as well as children from low (88·01 %), mid (89·10 %) and high (89·10 %) socio-economic status, are exposed to advertising of unhealthy products, but no significant difference was found between these proportions.
The majority of foods and beverages advertised to Colombian children are unhealthy. These findings highlight a need to implement statutory measures to reduce children’s exposure to unhealthy food advertising in Colombia, as obesity and overweight have been increasing among school-age children in Colombia, and exposure to television advertising of unhealthy foods is a known contributor to children’s food intake and obesity.
Wild poinsettia (Euphorbia heterophylla L.) is a troublesome broadleaf weed in grain production areas in South America. Herbicide resistance to multiple sites of action has been documented in this species, including protoporphyrinogen oxidase (PPO) inhibitors. We investigated the physiological and molecular bases for PPO-inhibitor resistance in a E. heterophylla population (RPPO) from Southern Brazil. Whole-plant dose–response experiments revealed a cross-resistance profile to three different chemical groups of PPO inhibitors. Based on dose–response parameters, RPPO was resistant to lactofen (47.7-fold), saflufenacil (8.6-fold), and pyraflufen-ethyl (3.5-fold). Twenty-four hours after lactofen treatment (120 g ha−1) POST, RPPO accumulated 27 times less protoporphyrin than the susceptible population (SPPO). In addition, RPPO generated 5 and 4.5 times less hydrogen peroxide and superoxide than SPPO, respectively. The chloroplast PPO (PPO1) sequences were identical between the two populations, whereas 35 single-nucleotide polymorphisms were found for the mitochondrial PPO (PPO2). Based on protein homology modeling, the Arg-128-Leu (homologous to Arg-98-Leu in common ragweed [Ambrosia artemisiifolia L.] was the only one located near the catalytic site, also in a conserved region of PPO2. The cytochrome P450 monooxygenase inhibitor malathion did not reverse resistance to lactofen in RPPO, and both populations showed similar levels of PPO1 and PPO2 expression, suggesting that metabolic resistance and PPO overexpression are unlikely. This is the first report of an Arg-128-Leu mutation in PPO2 conferring cross-resistance to PPO inhibitors in E. heterophylla.
Engineering of thermoelectric materials requires an understanding of thermal conduction by lattice and electronic degrees of freedom. Filled skutterudites denote a large family of materials suitable for thermoelectric applications where reduced lattice thermal conduction attributed to localized low-frequency vibrations (rattling) of filler cations inside large cages of the structure. In this work, a multi-wavelength method of exploiting x-ray dynamical diffraction in single crystals of CeFe4P12 is presented and applied to resolve the atomic amplitudes of vibrations. The results suggest that the vibrational dynamics of the whole filler-cage system is the actual active mechanism behind the optimization of thermoelectric properties.
This study aimed to assess the effects of the inhibition of nitric oxide synthase (NOS) on events that modulate bovine in vitro oocyte maturation. Cumulus–oocyte complexes (COCs) were cultured with hemisections (HSs) of the follicular walls in a maturation medium supplemented with different concentrations (0.1–10.0 mM) of Nω-nitro-l-arginine methyl ester hydrochloride (l-NAME). Controls consisted of COCs cultured in the presence (+HSs) or absence of HSs (–HSs) with no additional l-NAME supplementation. The following parameters were assessed: oocyte nuclear maturation stage; cumulus cell (CC) membrane integrity; nitrate/nitrite, progesterone, and estradiol concentrations in the culture medium at 22 h of cultivation; and the concentrations of cGMP and cAMP in COCs during the first hour of maturation. The addition of 1.0 mM l-NAME increased the percentage of oocytes that reached metaphase II (MII) and the percentage of intact CCs (P < 0.05). All l-NAME concentrations reduced the nitrate/nitrite concentrations (P < 0.05), but none affected steroid concentrations compared with control +HSs (P > 0.05). The addition of 1.0 mM l-NAME reduced cGMP concentrations at 3 h and increased cAMP concentrations in the first hour of culture (P < 0.05). Our findings suggest that the NOS/NO/cGMP pathway participates in meiosis progression (MI to MII) of the bovine oocytes matured in vitro in the presence of hemisections of the follicular walls. Lastly, the mechanisms that lead to the progression of meiosis after NOS inhibition do not involve changes in steroid production.
There is a substantial proportion of patients who drop out of treatment before they receive minimally adequate care. They tend to have worse health outcomes than those who complete treatment. Our main goal is to describe the frequency and determinants of dropout from treatment for mental disorders in low-, middle-, and high-income countries.
Respondents from 13 low- or middle-income countries (N = 60 224) and 15 in high-income countries (N = 77 303) were screened for mental and substance use disorders. Cross-tabulations were used to examine the distribution of treatment and dropout rates for those who screened positive. The timing of dropout was examined using Kaplan–Meier curves. Predictors of dropout were examined with survival analysis using a logistic link function.
Dropout rates are high, both in high-income (30%) and low/middle-income (45%) countries. Dropout mostly occurs during the first two visits. It is higher in general medical rather than in specialist settings (nearly 60% v. 20% in lower income settings). It is also higher for mild and moderate than for severe presentations. The lack of financial protection for mental health services is associated with overall increased dropout from care.
Extending financial protection and coverage for mental disorders may reduce dropout. Efficiency can be improved by managing the milder clinical presentations at the entry point to the mental health system, providing adequate training, support and specialist supervision for non-specialists, and streamlining referral to psychiatrists for more severe cases.
To assess antipsychotic medication in the treatment of schizophrenia, based on trial drop-out rates.
The studies included were randomised controlled trials that compared any of the four clinically best-established atypical antipsychotics (quetiapine, olanzapine, risperidone or clozapine) against either of two typical antipsychotics regarded as the gold standard (haloperidol or chlorpromazine).
Meta-analysis indicated less risk of all-cause patient withdrawal from atypical medication trials where dosage was flexible, in both the short, relative risk (RR) 0.70 (95% CI 0.64–0.76), P < 0.00001, and long term, RR 0.72 (0.65–0.80), P < 0.00001. Similar results were observed for withdrawal due to adverse events, RR: 0.54 (0.41–0.72), P < 0.0001. Nevertheless, the favourable effects of atypical medication disappeared in trials relying on fixed dosage.
We detected a significant positive effect in terms of the outcome of treatment discontinuation for atypical versus typical medication, though only where the use of flexible rather than fixed doses (closer to an experimental control situation) was possible.
Comorbidity has been defined as the coexistence of somatic and psychiatric diseases with diferent physiopatology in the same person, and it can appear simultaneously to the schizophrenia or during the patient's lifetime. There are two types of comorbidity: episodical or taking place during the lifetime of the patient. We can diffferenciate between comorbidity itself (in cluster, dependent or associated) to the so-called pseudo-comorbidity. Besides, comorbidity has been classified as a co-syndrome and it is considered a prognosis indicator of this disease, which can determine an increase in the rates related to relapses, worse response to treatment, less capacity to cope with social situations, and suicide in patients suffering from schizophrenia.
177 schizophrenic patients were assessed for affective symptoms and suicide behaviour. 24.3% were suffered for depression. 35% had a previous record of autolytic attempts. The rate of suicide history were higher among depressed schizophrenics (50%) than non-depressed schizophrenics (20%) (p<0,05).
We point out the clinic importance of suicide in schizophrenic patients suffering from depression. Moreover, the study shows the necessity to carry out longitudinal studies to recognize indicators of depression in advance and establish the diagnosis of depression, and, also, to acknowledge the importance of the gender factor in the depression of schizophrenic patients.
El registro arqueológico de cazadores-recolectores localizado en ambientes de altura ha sido ampliamente debatido en la literatura mundial. Las discusiones se han centrado en su funcionalidad, cronología, complementariedad con ambientes bajos y significado en los procesos de poblamiento de distintas regiones. Los Andes meridionales cuentan con un amplio espacio cordillerano dentro del cual se emplazan una serie de sitios arqueológicos localizados a aproximadamente 3.000 m snm. Las duras condiciones climáticas de estos ambientes, así como la presencia de estructuras habitacionales, despertó el interés de los investigadores en relación con su funcionalidad, tiempo de permanencia y manejo de los recursos locales. En este trabajo se presenta la información zooarqueológica de cuatro sitios de altura localizados en un sector de los Andes meridionales, en el sur de la provincia de Mendoza, Argentina: El Indígeno, Los Peuquenes, Laguna del Diamante S-4 y Risco de los Indios. El material arqueofaunístico analizado es evaluado a la luz de las características ambientales, los costos de transporte y la funcionalidad de estas locaciones en relación con los circuitos de explotación anual. Los resultados muestran un uso de taxones restringido, con un fuerte énfasis en el guanaco, y un escaso transporte de fauna desde y hacia pisos ecológicos localizados a menor altitud. Todo esto sugiere el uso de los sitios de manera residencial y no como lugares de obtención de presas para su procesamiento y traslado hacia localizaciones más bajas.
Superhydrophobic surfaces (SHSs) have the potential to reduce drag at solid boundaries. However, multiple independent studies have recently shown that small amounts of surfactant, naturally present in the environment, can induce Marangoni forces that increase drag, at least in the laminar regime. To obtain accurate drag predictions, one must solve the mass, momentum, bulk surfactant and interfacial surfactant conservation equations. This requires expensive simulations, thus preventing surfactant from being widely considered in SHS studies. To address this issue, we propose a theory for steady, pressure-driven, laminar, two-dimensional flow in a periodic SHS channel with soluble surfactant. We linearize the coupling between flow and surfactant, under the assumption of small concentration, finding a scaling prediction for the local slip length. To obtain the drag reduction and interfacial shear, we find a series solution for the velocity field by assuming Stokes flow in the bulk and uniform interfacial shear. We find how the slip and drag depend on the nine dimensionless groups that together characterize the surfactant transport near SHSs, the gas fraction and the normalized interface length. Our model agrees with numerical simulations spanning orders of magnitude in each dimensionless group. The simulations also provide the constants in the scaling theory. Our model significantly improves predictions relative to a surfactant-free one, which can otherwise overestimate slip and underestimate drag by several orders of magnitude. Our slip length model can provide the boundary condition in other simulations, thereby accounting for surfactant effects without having to solve the full problem.
The Altamira Yellowthroat Geothlypis flavovelata is endemic to north-eastern Mexico, with a restricted distribution due to the spatial arrangement of its major habitat: wetlands. Given the lack of information regarding this vulnerable and endemic landbird, here we describe and analyse the sites where we recorded it in Northern Veracruz, as well as its population density, and natural history information. Our results show that the average density of this endemic yellowthroat is 1.006 ind/ha, with more individuals recorded in Tecolutla when compared to Tuxpan. We found a strong association between the Altamira Yellowthroat and southern cat-tail Typha domingensis, although we found scenarios under which the presence of the cat-tail was not a determinant of Altamira Yellowthroat presence. In light of the strong anthropogenic pressures on wetlands in the region, the Altamira Yellowthroat has become highly vulnerable. Thus, if we aim to preserve this endemic species, together with other wetland-dependent species, it is crucial to moderate –and even stop– human pressures on these ecosystems and mitigate past damages.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Over recent decades, biomass gains in remaining old-growth Amazonia forests have declined due to environmental change. Amazonia’s huge size and complexity makes understanding these changes, drivers, and consequences very challenging. Here, using a network of permanent monitoring plots at the Amazon–Cerrado transition, we quantify recent biomass carbon changes and explore their environmental drivers. Our study area covers 30 plots of upland and riparian forests sampled at least twice between 1996 and 2016 and subject to various levels of fire and drought. Using these plots, we aimed to: (1) estimate the long-term biomass change rate; (2) determine the extent to which forest changes are influenced by forest type; and (3) assess the threat to forests from ongoing environmental change. Overall, there was no net change in biomass, but there was clear variation among different forest types. Burning occurred at least once in 8 of the 12 riparian forests, while only 1 of the 18 upland forests burned, resulting in losses of carbon in burned riparian forests. Net biomass gains prevailed among other riparian and upland forests throughout Amazonia. Our results reveal an unanticipated vulnerability of riparian forests to fire, likely aggravated by drought, and threatening ecosystem conservation at the Amazon southern margins.
The University of São Paulo Twin Panel (Painel USP de Gêmeos), based at the Institute of Psychology of the University of São Paulo, started formally in 2017. Our registry is new, but in only two years of formal existence, it comprises a volunteer sample of 4826 registered individuals (98% twins and 2% higher-order multiples), recruited at the University of São Paulo and by social media campaigns. Our main aim is to conduct and promote research with twins on psychological processes and behavior. The University of São Paulo is the largest higher education and research institution in South America, and the Painel USP de Gêmeos has great potential for fostering research on twin-related issues from a psychological perspective in Brazil and South America.
The South China Sea (SCS) is a biodiversity hotspot, however, most biodiversity surveys in the region are confined to shallow water reefs. Here, we studied the benthic habitat and fish assemblages in the upper mesophotic coral ecosystems (MCEs; 30–40 m) and SWRs (8–22 m) at three geographic locations (Luzon Strait; Palawan; and the Kalayaan Group of Islands) in the eastern SCS (also called the West Philippine Sea) using diver-based survey methods. Mean coral genera and fish species richness ranged from 17–25 (per 25 m2) and 11–17 (per 250 m2) in MCEs, respectively; although none of these were novel genera/species. Coral and fish assemblages were structured more strongly by location than by depth. Location differences were associated with the variability in benthic composition, wherein locations with higher hard coral cover had higher coral genera richness and abundance. Locations with higher algae and sand cover had higher diversity and density of fish herbivores and benthic invertivores. Fishing efforts may also have contributed to among-location differences as the highly exploited location had the lowest fish biomass. The low variation between depths may be attributed to the similar benthic composition at each location, the interconnectivity between depths due to hydrological conditions, fish motility, and the common fishing gears used in the Philippines that can likely extend beyond SWRs. Results imply that local-scale factors and anthropogenic disturbances probably dampen across-depth structuring in coral genera and fish species assemblages.