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The planetary-boundary-layer (PBL) flow and above is investigated for the central north coast of Brazil, an equatorial region spanning from 8° to 2°S. The daily PBL flow is controlled by vertical entrainment of horizontal momentum from a southerly large-scale flow associated with the Hadley cell, and by a mesoscale pressure gradient force (PGF) created by the differential heating between land and ocean. Near the coast, the flow is from the north-east quadrant comprising a small rotation, probably caused by a weak mesoscale PGF and a weak Coriolis force. Inland it is north-easterly in the morning, but deep mixing during the afternoon brings down momentum from above causing it to become south-easterly. The mesoscale PGF executes a daily 360° rotation at most of the stations. In the afternoon it points to land due to continuous heating of the land, and a sea breeze develops in the presence of the background flow. Once convection dies out, the transfer of horizontal momentum is reduced, and the marine-air layer can flow faster into the continent as a nocturnal jet. As the stable boundary layer grows thicker, this flow tends to be eliminated at the surface. By morning, the mesoscale PGF points north, forcing the inland flow to become south-easterly, while on the coast flow becomes almost easterly. This scenario repeats during dry and wet seasons and can be understood as a consequence of the south–north propagation of an atmospheric circulation resembling a helix with its rotation axis oriented parallel to the shoreline.

Alzheimer's disease (AD) is characterized mostly by memory decline. The current therapeutic arsenal for treating AD is limited, and the available drugs only produce symptomatic benefits, but do not stop disease progression. The search for effective therapeutic alternatives with multitarget actions is therefore imperative. One such a potential alternative is thiazolidin-4-one, a compound that exhibits anti-amnesic, anticholinesterase, and antioxidant activities. The aim of this study was evaluated the effects of 2-(4-(methylthio)phenyl)- 3-(3-(piperidin-1-yl)propyl) thiazolidin-4-one (DS12) on memory and neurochemical parameters in a model of AD induced by an intracerebroventricular injection of streptozotocin (STZ). Adult male rats were divided into five groups: I, control (saline); II, DS12 (10 mg/kg); III, STZ; IV, STZ + DS12 (10 mg/kg); V, STZ + donepezil (5 mg/kg). The rats were orally treated with DS12 and donepezil for a period of 20 days. Memory, acetylcholinesterase (AChE) activity, phosphorylated tau protein levels and oxidative stress were analyzed in the cerebral cortex, hippocampus, and cerebellum. Biochemical and hematological parameters were evaluated in the blood and serum. Memory impairment and the increase in AChE activity and phosphorylated tau protein level induced by STZ were prevented by DS12 and donepezil treatment. Streptozotocin induces an increase in reactive oxygen species levels and a decrease in catalase activity in the hippocampus, cerebral cortex, and cerebellum. DS12 treatment conferred protection from oxidative alterations in all brain structures. No changes were observed in serum biochemical parameters (glucose, triglycerides, cholesterol, uric acid, and urea) or hematological parameters, such as platelets, lymphocytes, hemoglobin, hematocrit, and total plasma protein. DS12 improved memory and neurochemical changes in an AD model and did not show toxic effects, suggesting the promising therapeutic potential of this compound.

Online-coupled meteorology-chemistry models provide powerful tools for more realistically simulation of current and future air quality with feedbacks between atmospheric composition and meteorology that cannot be considered in offline-coupled models. In this work, several state-of-science online-coupled models are applied to generate the best possible predictions of surface ozone (O3) and fine particulate matter (PM2.5) concentrations under current emission and climate conditions. Two ensemble methods are used to further reduce the model biases and errors including a simple ensemble mean based on an average of ensemble members, and a weighted ensemble mean based on the multi-linear regression. The skills of individual models and their ensembles are evaluated using available surface network data. Compared to individual models and the simple ensemble mean, the weighted ensemble predictions based on the multi-linear regression perform the best overall for both O3 and PM2.5. The model with best performance is selected to apply for future years to project the changes in air quality under various energy transition scenarios to support the development of emission control strategies. These results illustrate the current capability of the online-coupled models and the potential of weighted ensemble in generating the best possible estimates of air pollutant concentrations under current and future atmospheric conditions.

Zum Wandel von Zeugenschaft in wiederholten Befragungen von Holocaust-Überlebenden Was können wir aus den Erzählungen von Holocaust-Überlebenden lernen und warum erwarten wir von ihnen moralische Botschaften als Lehre aus den NS-Verbrechen? Diesen Fragen geht Daniel Schuch anhand von detaillierten Interviewanalysen nach. Den Ausgangspunkt bildet das bis heute kaum rezipierte Interviewprojekt von David P. Boder. Der lettisch-amerikanische Psychologe zeichnete bereits 1946 erstmals Stimmen von Überlebenden der NS-Verfolgung auf Tonband auf. Die Erzählungen dienten ihm als Forschungsmaterial, um die traumatischen Auswirkungen der Extremerfahrung zu analysieren. Boders Interviews gerieten in Vergessenheit. Jahrzehnte später erlebten Videointerviews mit Zeugen der NS-Verbrechen einen wahren Boom. Einige Personen, die Boder 1946 befragt hatte, wurden jeweils erneut in den 1990er und 2000er Jahren als Zeitzeugen interviewt. Durch den Vergleich von fünf jüdischen Überlebenden, die zu verschiedenen Zeitpunkten befragt wurden, lassen sich deutliche Transformationsprozesse der Zeugenschaft aufzeigen. Daniel Schuch analysiert Kontinuität und Wandel im Wiedererzählen der Überlebenden sowie die Auswirkungen von veränderten Erwartungshaltungen des jeweiligen Gegenübers.

Cholinergic system dysfunction, oxidative damage, and alterations in ion pump activity have been associated with memory loss and cognitive deficits in Alzheimer’s disease. 1,3-thiazolidin-4-ones have emerged as a class of compounds with potential therapeutic effects due to their potent anticholinesterase activity. Accordingly, this study investigated the effect of the 2-(4-(methylthio)phenyl)-3-(3-(piperidin-1-yl)propyl)thiazolidin-4-one (DS12) compound on memory, cholinergic and oxidative stress parameters, ion pump activity, and serum biochemical markers in a scopolamine-induced memory deficit model. Male Wistar rats were divided into four groups: I-Control; II-Scopolamine; III-DS12 (5 mg/kg) + scopolamine; and IV-DS12 (10 mg/kg) + scopolamine. The animals from groups III and IV received DS12 diluted in canola oil and administered for 7 days by gavage. On the last day of treatment, scopolamine (1 mg/kg) was administered intraperitoneally (i.p.) 30 min after training in an inhibitory avoidance apparatus. Twenty-four hours after scopolamine administration, the animals were subjected to an inhibitory avoidance test and were thereafter euthanized. Scopolamine induced memory deficits, increased acetylcholinesterase activity and oxidative damage, and decreased Na+/K+-ATPase activity in cerebral cortex and hippocampus. Pretreatment with DS12 prevented these brain alterations. Scopolamine also induced an increase in acetylcholinesterase activity in lymphocytes and whereas butyrylcholinesterase in serum and treatment with DS12 prevented these changes. In animals treated with DS12, no changes were observed in renal and hepatic parameters when compared to the control group. In conclusion, DS12 emerged as an important multitarget compound capable of preventing neurochemical changes associated with memory deficits.

A series of nineteen benzothiazin-4-ones from N-(3-aminopropyl) piperidine, 4-(2-aminoethyl)morpholine or 1-(2-aminoethyl)piperidine, aliphatic or aromatic aldehyde and thiosalicylic acid, were synthesized in good yields by multicomponent one-pot reactions. The solvent was toluene and this efficient procedure afforded the desired heterocycles in 5 h. Identification and characterization were achieved by NMR and GC–MS techniques. In vitro AChE activities of all compounds were evaluated in cerebral cortex and hippocampus of rats and in general, the results in cortex were more promising than hippocampus. The benzothiazinone 5Bd showed the best AChE inhibition activity IC50 8.48 μM (cortex) and IC50 39.80 μM (hippocampus). The cytotoxicity of seven compounds in MCR-5 human fibroblast cell by SRB test in 24 h were evaluated and 5Bd suggest preliminary safety, showing no cytotoxicity at 100 µM. Finally, these important findings could be a starting point for the development of new AChE inhibitors agents and will provide the basis for new studies.

This study aimed to analyze the time series behavior of the Southern Oscillation Index through techniques using Fast Fourier Transform, computing the autocorrelation function, and the calculation of the Hurst coefficient. The methodology of Hurst Exponent calculation uses different lags, which are computed in the time series of Southern Oscillation Index. The persistent behavior in the time series can be characterized by calculating the Hurst Exponent, seeking for more behavioral information, as the existence of persistence and/or terms of long-range memory in the series. The results show a persistence of the climate in terms of long-memory Southern Oscillation Index time series, which can help to understand a complex dynamic behavior in climate effects at global-scale level and specifically its influence in northeastern Brazil, in the region of the Alcântara Launch Center. The R package tseriesChaos was used in the analysis of the Southern Oscillation Index time series, estimating the largest Lyapunov exponent, which indicates the existence of chaotic behavior in time series. The resampling technique was used in a permutation test between the surface wind data in the São Luís airport, Maranhão State, and the Southern Oscillation Index. The permutation test results showed that the time series of monthly average wind speed in the São Luís airport is correlated with the variability of Southern Oscillation Index, statistically correlated to the confidence interval at the 5% level. The results showed the possibility of using autoregressive models to represent average variable meteorology in the behavior analysis as well as trends in the climate, more specifically a possible climatic influence of El Niño-Southern Oscillation in wind strength in the Alcântara Launch Center.

The present study assessed the 2,3-substituted-1,3-thiazolidin-4-ones antinociceptive potential looking at the acute nociception model induced by thermal stimulation in mice. This was done to contribute to the development of new analgesic drugs, in addition to the fact that 4-thiazolidinones are an important scaffold associated with many pharmacological activities. The synthesized compounds were characterized by GC-MS and NMR of 1H and 13C and administered at a dose of 100 mg/kg hydrochloride salt (ip). Sodium dipyrone (250 and 500 mg/Kg; ip) and tramadol hydrochloride (25 and 50 mg/Kg; ip) were used as positive controls. The hot plate test was done at a temperature of 50 ± 0.1 °C and animals assessed at 30, 60, and 90 min after the drugs were administered. Among the fourteen compounds tested, nine (5Aa, 5Ab, 5Ac, 5Ad, 5Ba, 5Bb, 5Bd, 5Ea, and 5Fa) showed significant increases in latency time when compared to saline (negative control) and compared to sodium dipyrone (500 mg/Kg; ip) in a 30-min assessment. The highest latency times were obtained for 3-(2-piperidin-1-yl)ethyl)thiazolidin-4-one derivatives (5Ab, 5Ac, and 5Ad). This highlights three findings about the chemical structure that improve activity: (i) an ethylenic link; (ii) a six-membered piperidine; (iii) an aliphatic substituent at the 2-position of thiazolidinone ring.

Glioblastoma multiforme (GBM) is the worst form of primary brain tumor, which has a high rate of infiltration and resistance to radiation and chemotherapy, resulting in poor prognosis for patients. Recent studies show that thiazolidinones have a wide range of pharmacological properties including antimicrobial, anti-inflammatory, anti-oxidant and anti-tumor. Here, we investigate the effect antiglioma in vitro of a panel of sixteen synthetic 2-aryl-3-((piperidin-1-yl)ethyl)thiazolidin-4-ones where 13 of these decreased the viability of glioma cells 30–65% (100 μM) compared with controls. The most promising compounds such as 4d, 4l, 4m and 4p promoted glioma reduction of viability greater than 50%, were further tested at lower concentrations (12.5, 25, 50 and 100 μM). Also, the data showed that the compounds 4d, 4l, 4m and 4p induced cell death primarily through necrosis and late apoptosis mechanisms. Interestingly, none of these 2-aryl-3-((piperidin-1-yl)ethyl)thiazolidin-4-ones were cytotoxic for primary astrocytes, which were used as a non-transformed cell model, indicating selectivity. Our results also show that the treatment with sub-therapeutic doses of 2-aryl-3-((piperidin-1-yl)ethyl)thiazolidin-4-ones (4d, 4l and 4p) reduced in vivo glioma growth as well as malignant characteristics of implanted tumors such as intratumoral hemorrhage and peripheral pseudopalisading. Importantly, 2-aryl-3-((piperidin-1-yl)ethyl)thiazolidin-4-ones treatment did not induce mortality or peripheral damage to animals. Finally, 2-aryl-3-((piperidin-1-yl)ethyl)thiazolidin-4-ones also changed the nitric oxide metabolism which may be associated with reduced growth and malignity characteristics of gliomas. These data indicates for the first time the therapeutic potential of synthetic 2-aryl-3-((piperidin-1-yl)ethyl)thiazolidin-4-ones to GBM treatment.

The present study assessed the biological potential of fourteen 1,3-thiazolidin-4-ones evaluating the antiglioma effect through decreasing of cell viability of glioblastoma multiform cells. The new compounds were efficient synthesized through multicomponent or multicomponent one-pot procedures in moderate to good yields (22–86%) from two arenealdehydes (4-(methylthio)benzaldehyde and 4-(methylsulfonyl)benzaldehyde), seven amines (aromatic and aliphatic) and mercaptoacetic acid. The compounds were identified and characterized by GC/MS and NMR, five of them by HRMS. Six thiazolidinones showed significant effect of decreasing cell viability compared to standard drug TMZ at 100 μM in 72 h in C6 cell line by MTT assay. The compounds 5b, 5e, 5g and 6e showed the best results in the screening at 100 μM and were analyzed at different concentrations (5, 25, 50, 100 and 250 μM). Compounds 5b and 5e showed statistical difference at 5 μM, 6e at 25 μM and 5g at 50 μM in 72 h of treatment. The cytotoxicity study in primary astrocytes cells was evaluated and none of fourteen compounds showed toxicity at 100 μM, eight of them were not cytotoxic at 250 μM, both in 72 h. In addition, the propidium iodide assay demonstrated that the compounds might induce cell death by necrosis. In conclusion, this work reports at least four compounds (5b, 5e, 5g and 6e) with potential anti-tumor effect against glioblastoma multiform cell presenting activity at low concentrations and safe profile of cytotoxicity.

Air quality models are tools capable to predict the physical and chemical processes that affect air pollutants as they disperse and reacts in the atmosphere. These models need input containing meteorological data, terrestrial data and emissions. Meteorological and terrestrial data comes from different sources such as meteorological stations and satellite images which are important to represent the current state of the atmosphere and are available at least on a daily frequency. On the other hand, the emission data comes from pollution inventories generated mainly from governmental reports, this data needs to be processed by various reasons such as the correction of outdated emissions, for combining inventories or to speciate the emitted pollutants to different chemical mechanisms. EmissV is a code written into a high-level programming language to create emissions input for these atmospheric models. The emissions from EmissV are coherent with the total and the spatial distribution of emissions obtained from other preprocessors.

In this paper, we analyze the variability of the ozone concentration over São Paulo Macrometropolis, as well the factors, whichdetermined the tendency observed in the last two decades. Time series of hourly ozone concentrations measured at 16 automatedstations from an air quality network from 1996 to 2017 were analyzed. The temporal variability of ozone concentrations exhibitswell-defined daily and seasonal patterns. Ozone presents a significant positive correlation between the number of cases (thresh-olds of 100–160μgm−3) and the fuel sales of gasohol and diesel. The ozone concentrations do not exhibit significant long-termtrends, but some sites present positive trends that occurs in sites in the proximity of busy roads and negative trends that occurs insites located in residential areas or next to trees. The effect of atmospheric process of transport and ozone formation was analyzedusing a quantile regression model (QRM). This statistical model can deal with the nonlinearities that appear in the relationship ofozone and other variables and is applicable to time series with non-normal distribution. The resulting model explains 0.76% ofthe ozone concentration variability (with global coefficient of determinationR1= 0.76) providing a better representation than anordinary least square regression model (with coefficient of determinationR2= 0.52); the effect of radiation and temperature arethe most critical in determining the highest ozone quantiles

The flow patterns over a finite square cylinder of aspect ratio of 3 were analyzed experimentally in a subsonic wind tunnel using the time-resolved particle image velocimetry (TR - PIV) techniques. The near wake flow structures and vortex shedding characteristics were investigated using mean flow analysis, spectral analysis and proper orthogonal decomposition (POD). The cylinders were fixed on a elliptical leading edge flat plate, creating a boundary layer which interacted with the cylinder wake. The 2D PIV measurements were conducted at a low horizontal plane, z/h = 0.3, to investigate possible boundary layer interactions. Due to the complexity of the phenomena, the flow was characterized both in terms of average behavior and time-resolved velocity fields. Both symmetrical and anti-symmetrical vortices structures occur in the cylinder wake, which can be identified based on the coefficients of the first four POD modes. The results indicated that the alternating Karman vortex structures are dominant, described by the first two POD modes.

A estrutura do campo de vento e da turbulência atmosférica gerada no interior de uma cavidade rasa é analisada com o uso de ensaios realizados em túnel de vento e simulação numérica com um modelo bidimensional de grandes turbilhões (LES). As cavidades são maquetes estáticas, que podem representar regiões de pequenas clareiras na Amazônia ou de "canyons" urbanos representando a geometria de cidades modernas. Os resultados sugerem que, apesar das diferenças de escalas, a organização da turbulência nos dois experimentos contém similaridades em algumas regiões. Foi verificada a dependência que a intensidade da turbulência, o perfil do vento e termos do balanço de Energia Cinética Turbulenta têm com a velocidade do fluxo livre, com as dimensões (largura) da cavidade e com a posição relativa dentro da cavidade. The structure of the wind field and atmospheric turbulence generated inside a shallow cavity is analyzed using wind tunnel tests and a 2-D Large-Eddy Simulation (LES) model. The cavities are static mock-up that can represent small clearings inside forest in Amazonia or urban canyons representing the geometry of modern cities. The results suggest that, despite differences in the scales, the organization of turbulence in the two experiments contains similarities in some regions. It was verified the dependency of the turbulence, wind profile and Turbulent Kinetic Energy dependence against flow above canopy, its size and its relative position inside the gap.

Este trabalho relata um escoamento estratificado e turbulento, no qual a superficie e mais fria que o ambiente sobre ela. Dessa forma, verifica-se a influencia da estratificacao sobre os perfis de vento e temperatura.

O perfil de vento e a turbulencia foram estudados a partir de medidas obtidas com um anemometro de fio quente em ensaios de tunel de vento com um modelo de cavidade rasa. Foi determinada a Escala Integral Euleriana e os resultados sugerem que a estrutura da turbulencia e controlada, principalmente, pela entrada de energia a sotavento da cavidade.

The atmospheric flow near the surface and in the planetary boundary layer (PBL) are investigated for the coastal part of Maranhão state. Near the coast in the PBL the flow is predominantly from the northeast quadrant with its meridional component increasing during the day and being from north-northeast and decreasing during the course of the night to be from east-northeast at early morning. The result of this is a small counterclockwise rotation but with no flow reversals. Through an analysis of extensive radiosonde data it is found that the flow above the PBL is predominantly southeasterly for the region. It is consequence of the outflow from the descending branch of the large-scale circulation of the Hadley cell. For stations further inland the flow is from approximately northeast during period between morning to noon but rotating clockwise to become from southeast-east (SEE) sector at early evening. The clockwise rotation continues in the afternoon and the wind becomes from south, and later southwest when in the evening it quickly becomes from north. The wind rotation during this period is mainly determined by an oscillating surface pressure gradient-force. During the night the local surface wind tendency is not controlled by the gradient-force probably because the air has to go against higher terrain and negative buoyancy becomes an important force of the momentum balance. The oscillating surface pressure-gradient-force is a response to a sea-breeze circulation. In the coast, we speculate that the flow does not reverse its meridional component because the surface pressure-gradient point south there for most of the time.

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