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Chrysosporum ovalisporum is a cylindrospermopsin toxin producing cyanobacterium that was reported in several lakes and reservoirs. Its growth dynamics and toxin distribution in field remain largely undocumented. Chrysosporum ovalisporum was reported in 2009 in Karaoun Reservoir, Lebanon. We investigated the factors controlling the occurrence of this cyanobacterium and vertical distribution of cylindrospermopsin in Karaoun Reservoir. We conducted bi-weekly sampling campaigns between May 2012 and August 2013. Results showed that Chrysosporum ovalisporum is an ecologically plastic species that was observed in all seasons. Unlike the high temperatures, above 26 °C, which is associated with blooms of Chrysosporum ovalisporum in Lakes Kinneret (Israel), Lisimachia and Trichonis (Greece) and Arcos Reservoir (Spain), Chrysosporum ovalisporum in Karaoun Reservoir bloomed in October 2012 at a water temperature of 22 °C during weak stratification. Cylindrospermopsin was detected in almost all water samples even when Chrysosporum ovalisporum was not detected. Chrysosporum ovalisporum biovolumes and cylindrospermopsin concentrations were not correlated (n = 31, r2 = −0.05). Cylindrospermopsin reached a maximum concentration of 1.7 µg L−1. The vertical profiles of toxin concentrations suggested its possible degradation or sedimentation resulting in its disappearance from the water column. The field growth conditions of Chrysosporum ovalisporum in this study revealed that it can bloom at the subsurface water temperature of 22 °C increasing the risk of its development and expansion in lakes located in temperate climate regions.

Os imbróglios que permeiam a educação não se esgotam nos já conhecidos embates entre o poder público e a classe educacional. Uma das dimensões mais danosas da miséria à qual a educação está submetida reside na educação menor, no papel do professor, na sua formação e na sua postura perante os outros, no caso seus alunos. Para a promoção de alguma transformação nas relações que orbitam esse pequeno universo, lança-se mão de uma possível sintonia entre o Anarquismo Epistemológico de Paul Feyerabend e o Rizoma de Gilles Deleuze e Félix Guattari. Tendo a Interdisciplinaridade como fim e as concepções de Feyerabend, Deleuze e Guattari como meio, este trabalho lança um novo desafio: fazer uma reflexão sobre os problemas educacionais tendo como ponto de partida e como ponto de chegada o professor. A formação de uma consciência de que a forma (método) e o conteúdo (conhecimento) não devem acorrentar o sujeito, mas serem superados quando se impõem como obstáculos à ação de espíritos livres.

Superparamagnetic iron oxide nanoparticles (SPIONs) have shown great potential in biomedicine due to their high intrinsic magnetization behaviour. These are small particles of magnetite or maghemite, and when coated, their surface oxidation is prevented, their aggregation tendency is reduced, their dispersity is improved, and the stability and blood circulation time are increased, which are mandatory requirements in biomedical applications. In this work, SPIONs were synthesized in air through a reduction-precipitation method and coated with four different polymers (Polyethylene glycol(PEG) 1000/6000 and dextran T10/T70). All the synthesized samples were structurally and magnetically characterized by transmission electron microscopy, Fourier transform infra-red spectroscopy, X-ray powder diffraction, Mössbauer spectroscopy, and Superconducting Quantum Interference Device (SQUID) magnetometry. SPIONs centrifuged and dried in vacuum with an average diameter of at least 7.5 nm and a composition ≤60% of maghemite and ≥40% of magnetite showed the best magnetization results, namely a saturation magnetization of ~64 emu/g at 300 K, similar to the best reported values for SPIONs prepared in controlled atmosphere. As far as SPIONs’ coatings are concerned, during their preparation procedure, surface polymers must be introduced after the SPIONs’ precipitation. Furthermore, polymers with shorter chains do not affect the SPIONs’ magnetization performance, although longer chain polymers significantly decrease the coated particle magnetization values, which is undesirable.

Worldwide, eutrophication and cyanobacteria blooms in lakes and reservoirs are a great concern for water resources management. Coupling a catchment hydrological model and a lake model has been a strategy to assess the impact of land use, agricultural practices and climate change on water quality. However, research has mainly focused on large lakes, while urban reservoirs and their catchments, especially in tropical regions, are still poorly studied despite the wide range of ecosystem services they provide. An integrated modelling approach coupling the hydrological model Storm Water Management Model SWMM and the lake ecological model DYRESM-CAEDYM is proposed for Lake Pampulha (Brazil). Scenarios of increased imperviousness of the catchment and of reduction in the load of nutrients and total suspended solids (TSS) in dry weather inflow were simulated. Runoff water quality simulations presented a fair performance for TSS and ammonium (NH4+) while the dynamics of total phosphorus (TP) and nitrate (NO3−) were poorly captured. Phytoplankton dynamics in the lake were simulated with good accuracy (Normalized Mean Absolute Error, NMAE = 0.24 and r = 0.89 in calibration period; NMAE = 0.55 and r = 0.54 in validation period). The general trends of growth, decline and the magnitude of phytoplankton biomass were well represented most of the time. Scenario simulations suggest that TP reduction will decrease cyanobacteria biomass and delay its peaks as a consequence of orthophosphate (PO43−) concentration reduction in the lake surface layers. However, even decreasing TP load into Lake Pampulha by half would not be sufficient to achieve the water quality objective of a maximum concentration of 60 µg chla L−1. Increased imperviousness in the catchment will raise runoff volume, TSS, TP and NO3− loads into Lake Pampulha and promote greater cyanobacteria biomass, mainly in the beginning of the wet season, because of additional nutrient input from catchment runoff. Recovering Lake Pampulha water quality will require the improvement of the sanitation system. The lake water quality improvement will also require more sustainable and nature-based solutions for urban drainage in order to reduce non-point pollution through infiltration and retention of stormwater and to enhance natural processes, such as chemical sorption, biodegradation and phytoremediation. The integrated modelling approach here proposed can be applied for other urban reservoirs taking advantage of existing knowledge on Lake Pampulha.

The Sentinel satellite fleet of the Copernicus Programme offers new potential to map and monitor plant traits at fine spatial and temporal resolutions. Among these traits, leaf area index (LAI) is a crucial indicator of vegetation growth and an essential variable in biodiversity studies. Numerous studies have shown that the radiative transfer approach has been a successful method to retrieve LAI from remote-sensing data. However, the suitability and adaptability of this approach largely depend on the type of remote-sensing data, vegetation cover and the ecosystem studied. Saltmarshes are important wetland ecosystems threatened by sea level rise among other human- and animal-induced changes. Therefore, monitoring their vegetation status is crucial for their conservation, yet few LAI assessments exist for these ecosystems. In this study, the retrieval of LAI in a saltmarsh ecosystem is examined using Sentinel-2 and RapidEye data through inversion of the PROSAIL radiative transfer model. Field measurements of LAI and some other plant traits were obtained during two succeeding field campaigns in July 2015 and 2016 on the saltmarsh of Schiermonnikoog, a barrier island of the Netherlands. RapidEye (2015) and Sentinel-2 (2016) data were acquired concurrent to the time of the field campaigns. The broadly employed PROSAIL model was inverted using two look-up tables (LUTs) generated in the spectral band’s settings of the two sensors and in which each contained 500,000 records. Different solutions from the LUTs, as well as, different Sentinel-2 spectral subsets were considered to examine the LAI retrieval. Our results showed that generally the LAI retrieved from Sentinel-2 had higher accuracy compared to RapidEye-retrieved LAI. Utilising the mean of the first 10 best solutions from the LUTs resulted in higher R2 (0.51 and 0.59) and lower normalised root means square error (NRMSE) (0.24 and 0.16) for both RapidEye and Sentinel-2 data respectively. Among different Sentinel-2 spectral subsets, the one comprised of the four near-infrared (NIR) and shortwave infrared (SWIR) spectral bands resulted in higher estimation accuracy (R2 = 0.44, NRMSE = 0.21) in comparison to using other studied spectral subsets. The results demonstrated the feasibility of broadband multispectral sensors, particularly Sentinel-2 for retrieval of LAI in the saltmarsh ecosystem via inversion of PROSAIL. Our results highlight the importance of proper parameterisation of radiative transfer models and capacity of Sentinel-2 spectral range and resolution, with impending high-quality global observation aptitude, for retrieval of plant traits at a global scale.

A new extraction phase based on hydrogel disks of polyvinyl alcohol (PVOH) and pectin was proposed, characterized and evaluated for the extraction of six steroidal hormones (estriol, estrone, 17β-estradiol, 17α-ethinylestradiol, progesterone, and testosterone) in aqueous samples with subsequent determination by gas chromatography-tandem mass spectrometry (GC-MS/MS) after the derivatization procedure. The developed extraction procedure was based on the solid phase extraction (SPE) technique, but employed hydrogel as the sorbent phase. The effects of several parameters, including the amount and composition of the sorbent phase, pH, sample volume, flow rate, and gel swelling over the extraction efficiency, were evaluated. Gels with lower swelling indexes and larger amounts of sorbent ensured higher extraction yields of analytes. The main benefits of using the PVOH/pectin-based hydrogel as the extraction phase are the ease of synthesis, low-cost preparation, and the possibility of reusing the extraction disks. Limits of quantification of 0.5 μg L−1 for estrone and 17β-estradiol, and 1 μg L−1 for testosterone, 17α-ethinylestradiol, progesterone, and estriol were obtained. Accuracy values ranged from 80% to 110%, while the inter-assay precision ranged from 0.23% to 22.2% and the intra-assay from 0.55% to 12.3%. Since the sorbent phase has an amphiphilic character, the use of hydrogels is promising for the extraction of medium-to-high polarity compounds.

BackgroundIn the USA, oral nirmatrelvir-ritonavir is authorised for use in patients aged 12 years or older with mild-to-moderate COVID-19 who are at risk of progression to severe disease and hospitalisation. We aimed to establish the effectiveness of nirmatrelvir-ritonavir in preventing hospital admissions and death in people with COVID-19 in an outpatient prescribing context in the USA.MethodsIn this matched observational outpatient cohort study in the Kaiser Permanente Southern California (CA, USA) health-care system, data were extracted from electronic health records of non-hospitalised patients aged 12 years or older who received a positive SARS-CoV-2 PCR test result (their index test) between April 8 and Oct 7, 2022, and had not received another positive test result within the preceding 90 days. We compared outcomes between people who received nirmatrelvir-ritonavir and those who did not receive nirmatrelvir-ritonavir by matching cases by date, age, sex, clinical status (including care received, the presence or absence of acute COVID-19 symptoms at testing, and time from symptom onset to testing), vaccination history, comorbidities, health-care seeking during the previous year, and BMI. Our primary endpoint was the estimated effectiveness of nirmatrelvir-ritonavir in preventing hospital admissions or death within 30 days of a positive test for SARS-CoV-2.Findings7274 nirmatrelvir-ritonavir recipients and 126 152 non-recipients with positive SARS-CoV-2 tests were included in our study. 5472 (75·2%) treatment recipients and 84 657 (67·1%) non-recipients were tested within 5 days of symptom onset. Nirmatrelvir-ritonavir had an overall estimated effectiveness of 53·6% (95% CI 6·6-77·0) in preventing hospital admission or death within 30 days of a positive test for SARS-CoV-2, which increased to 79·6% (33·9-93·8) when nirmatrelvir-ritonavir was dispensed within 5 days of symptom onset. Within the subgroup of patients tested within 5 days of symptom onset and whose treatment was dispensed on the day of their test, the estimated effectiveness of nirmatrelvir-ritonavir was 89·6% (50·2-97·8).InterpretationIn a setting with high levels of COVID-19 vaccine uptake, nirmatrelvir-ritonavir effectively reduced the risk of hospital admission or death within 30 days of a positive outpatient SARS-CoV-2 test.FundingUS Centers for Disease Control and Prevention and US National Institutes of Health.

Bacterial detection plays an important role in protecting public health and safety, and thus, substantial research efforts have been directed at developing bacterial sensing methods that are sensitive, specific, inexpensive, and easy to use. We have recently reported a novel “mix-and-read” assay where a fluorogenic DNAzyme probe was used to detect model bacterium E. coli. In this work, we carried out a series of optimization experiments in order to improve the performance of this assay. The optimized assay can achieve a detection limit of 1000 colony-forming units (CFU) without a culturing step and is able to detect 1 CFU following as short as 4 h of bacterial culturing in a growth medium. Overall, our effort has led to the development of a highly sensitive and easy-to-use fluorescent bacterial detection assay that employs a catalytic DNA.

Introduction: The lifestyle (LS) have been constituted as a going concern factor in today’s society, since low levels of health and well -being may lead to adverse consequences , especially in vulnerable groups such as college students, whose behavior acquired at this stage can be extended to other stages of life. Model of the study: Cohort study. Objectives: This study aimed to evaluate the lifestyle of college students during the first two years of the undergraduate program. Methods: The study enrolled, students who enrolled in undergraduate programs of Teacher Education Center of the Federal University of Bahia Reconcavo in the first half of the school year 2010. The lifestyle was determined by using the selfadministered questionnaire “Style life Fantastic”. We used the Chi-square test, McNemar test and relative risk (RR), considering p

The Zika virus (ZIKV) is a flavivirus of the family Flaviviridae, which is similar to dengue virus, yellow fever and West Nile virus. Recent outbreaks in South America, Latin America, the Caribbean and in particular Brazil have led to concern for the spread of the disease and potential to cause Guillain-Barré syndrome and microcephaly. Although ZIKV has been known of for over 60 years there is very little in the way of knowledge of the virus with few publications and no crystal structures. No antivirals have been tested against it either in vitro or in vivo. ZIKV therefore epitomizes a neglected disease. Several suggested steps have been proposed which could be taken to initiate ZIKV antiviral drug discovery using both high throughput screens as well as structure-based design based on homology models for the key proteins. We now describe preliminary homology models created for NS5, FtsJ, NS4B, NS4A, HELICc, DEXDc, peptidase S7, NS2B, NS2A, NS1, E stem, glycoprotein M, propeptide, capsid and glycoprotein E using SWISS-MODEL. Eleven out of 15 models pass our model quality criteria for their further use. While a ZIKV glycoprotein E homology model was initially described in the immature conformation as a trimer, we now describe the mature dimer conformer which allowed the construction of an illustration of the complete virion. By comparing illustrations of ZIKV based on this new homology model and the dengue virus crystal structure we propose potential differences that could be exploited for antiviral and vaccine design. The prediction of sites for glycosylation on this protein may also be useful in this regard. While we await a cryo-EM structure of ZIKV and eventual crystal structures of the individual proteins, these homology models provide the community with a starting point for structure-based design of drugs and vaccines as well as a for computational virtual screening.

Several technical and scientific publications have been made available focussing on Bridge Weight-in-Motion (BWIM) concerning railway bridges. On the contrary, BWIM analysis on road bridges are more scarce and therefore, this work intends to provide a contribution by presenting the BWIM analysis performed on two major road bridges in Portugal – Lezíria Bridge and Pinhão Bridge. These bridges are equipped with electric and optical strain gauges, acquisi­tion systems with features that allow high sampling rates. Based on the collected data and focussing on the bridges’ life­time, a probabilistic approach to quantify extreme traffic loads was implemented using extreme distribution functions. The bridges’ behaviour to these extreme traffic loads is numerically evaluated and a comparison with the alarm levels established by the bridge designers is performed. Although the bridge’s safety is not compromised, it was concluded that the representativeness of the observation period is a critical issue and the analysis of this kind of results must be care­fully considered. A comprehensive discussion about this matter is carried out at the end of this work. First published online: 13 Dec 2015

Hysterectomy is the most common surgical gynecologic procedure, which is frequently related to the treatment of leiomyoma. The laparoscopic hysterectomy is associated with a shorter hospital stay, fewer infection rates, and a faster return to daily activities. Most gynecologists do not recommend a hysterectomy via the vagina or a laparoscopic-assisted vaginal hysterectomy (LAVH) in the case of a uterus weighing more than 300 g. This case report presents the case of an LAVH undertaken in a 43-year-old patient with a uterus weighing 2,800 g. There are no definite guidelines concerning the procedure for a large uterus, and the literature is vague regarding the best surgical procedure for these cases. The size of the uterus does not seem to be an absolute contraindication for endoscopic surgery. This procedure relies entirely on the surgeon’s ability

The objective of this study was to evaluate the performance of two genotypes of elephant grass, fertilized with and without N, for biomass production for energy use under the edaphoclimatic conditions of the Cerrado. The genotypes Roxo and Paraíso, grown in a field experiment in a Latosol in the Cerrado region were evaluated for biomass yield, nitrogen accumulation, C:N and stem:leaf ratios, fibre, ash and P and K contents and calorific value. The accumulated dry biomass ranged from 30 to 42 Mg ha-1 and showed no response to nitrogen fertilization with the lowest biomass obtained by the genotype Paraíso and the highest by Roxo. The total N accumulation followed the same pattern as for dry matter, ranging from 347 to 539 kg N ha-1. C:N and stem:leaf ratio of the biomass produced did not vary with treatments. The fibre contents were higher in genotype Paraíso and the highest levels of ash in the genotype Roxo. The K content in the biomass was higher in genotype Roxo and P did not vary between genotypes. The calorific value averaged 18 MJ kg-1 of dry matter and did not vary with the levels of N in leaves and stems of the plant. Both genotypes, independent of N fertilization, produced over 30 Mg ha-1 of biomass under Cerrado conditions.O presente trabalho objetivou avaliar o desempenho de dois genótipos de capim‑elefante para produção de biomassa para uso energético, em condições edafoclimáticas do Cerrado, fertilizados, ou não, com N. Avaliaram-se os rendimentos de biomassa, o acúmulo de nitrogênio, as relações C/N e colmo/folha, os teores de fibra, as cinzas da biomassa, os teores de K e P da biomassa e poder calorífico dos genótipos Paraíso e Roxo, cultivados em Latossolo, na região de Cerrado. A biomassa seca acumulada variou de 30 a 42 Mg ha-1, não havendo resposta à fertilização nitrogenada, sendo os menores obtidos com o genótipo Paraíso, e os maiores, com o Roxo. A acumulação total de N seguiu o mesmo comportamento da matéria seca, variando de 347 a 539 kg ha-1 de N. As relações C/N e colmo/folha da biomassa produzida não variaram com os tratamentos. Os teores de fibra foram maiores no genótipo Paraíso, e os teores de cinza, maiores no genótipo Roxo. O teor de K na biomassa de capim-elefante foi maior no genótipo Roxo, e o de P não variou entre os genótipos. O poder calorífico foi, em média, de 18 MJ kg-1 de matéria seca, e não variou em função dos teores de N nas folhas e nos colmos da planta. Ambos os genótipos, independentemente da fertilização com N, produzem acima de 30 Mg ha-1 de biomassa, em condições de Cerrado.

In industrialized countries, cerebral palsy affects 2.5‰ of preterm and term infants. At a neurochemical level, the massive release of glutamate constitutes a major process leading to excitotoxicity and neonatal brain lesions. Previous studies, conducted in the laboratory, revealed that, in δ/δVEGFA transgenic mice, glutamate-induced brain lesions are exacerbated suggesting that VEGFA could play a protective action against excitotoxicity. Using a model of cultured cortical brain slices, the aim of the study was to characterize the central effects of VEGF against glutamate-induced excitotoxicity in neonates. Exposure of brain slices to glutamate induced a strong increase of necrotic cell death in the deep cortical layer VI and a decrease of apoptotic death in superficial layers II–IV. When administered alone, a 6-h treatment with VEGFA had no effect on both apoptotic and necrotic deaths. In contrast, VEGFA abolished the glutamate-induced necrosis observed in layer VI. While MEK and PI3-K inhibitors had no effect on the protective action of VEGFA, L-NAME, a pan inhibitor of NOS, abrogated the effect of VEGFA and exacerbated the excitotoxic action of glutamate. Calcimetry experiments performed on brain slices revealed that VEGFA reduced the massive calcium influx induced by glutamate in layer VI and this effect was blocked by L-NAME. Neuroprotective effect of VEGFA was also blocked by LNIO and NPLA, two inhibitors of constitutive NOS, while AGH, an iNOS inhibitor, had no effect. Nitrite measurements, electron paramagnetic resonance spectroscopy and immunohistochemistry indicated that glutamate was a potent inducer of NO production via activation of nNOS in the cortical layer VI. In vivo administration of nNOS siRNA promoted excitotoxicity and mimicked the effects of L-NAME, LNIO and NPLA. A short-term glutamate treatment increased nNOS Ser1412 phosphorylation, while a long-term exposure inhibited nNOS/NR2B protein–protein interactions. Altogether, these findings indicate that, in deep cortical layers of mice neonates, glutamate stimulates nNOS activity. Contrasting with mature brain, NO production induced by high concentrations of glutamate is neuroprotective and is required for the anti-necrotic effect of VEGFA.

Historians claim that European colonizers of the northern coast of Rio de Janeiro State found vast herbaceous fields when arrived in this region. Hypotheses about the origin of these fields include forest burning by the Goitacás indians and periodical floods by the Paraíba do Sul River and the lagoon system. The palynologycal analysis of two lake cores obtained in the municipality of Campos dos Goytacazes revealed opening episodes of hygrophilous forest and the establishment of field vegetation, recorded at ca. 6,500 and ca. 4,000 14C yr BP. The partial replacement of forest by field vegetation in the first episode was probably caused by floods of the lower areas during the development of the Holocene lagoon phase. During the second episode, successions of vegetational patterns occurred due to lowering of the sea level. Drying and enlarging of the coastal plain have allowed its colonization by herbs and heliophyte plants. The palynological analysis does not provide any evidence that sustains the theories of use of fire and agricultural activities by indigenous groups during these periods.Os historiadores citam que os europeus colonizadores da costa norte do Estado do Rio de Janeiro encontraram vastos campos herbáceos quando chegaram a essa região. As hipóteses sobre a origem desses campos incluem aplicação de "queimada"pelos índios Goitacás e periódicas inundações do rio Paraíba do Sul e sistemas lagunares. A análise palinológica de dois testemunhos de sondagem obtidos no município de Campos dos Goytacazes revelou epsódios de abertura da floresta higrófila e o estabelecimento da vegetação campestre, datado sem ca. 6.500 e 4.000 14C anos AP. O primeiro epsódio de substituição parcial da floresta pela vegetação campestre se deu provavelmente pelas inundações das áreas baixas durante o desenvolvimento da fase lagunar holocênica. No segundo epsódio, os padrões de sucessão da vegetação ocorreram como consequência do abaixamento do nível do mar. O ressecamento e a progressão da planície costeira permitiram sua colonização pelas plantas herbáceas heliófitas. A análise palinológica não forneceu qualquer evidência que apoie as teorias do uso do fogo e da prática de atividades agrícolas por grupos indígenas durante esses períodos.

Em face da importância em conhecer a evapotranspiração (ET) para uso racional da água na irrigação no contexto atual de escassez desse recurso, algoritmos de estimativa da ET a nível regional foram desenvolvidos utilizando-se de ferramentas de sensoriamento remoto. Este estudo objetivou aplicar o algoritmo SEBAL (Surface Energy Balance Algorithms for Land) em três imagens do satélite Landsat 5, do segundo semestre de 2006. As imagens correspondem a áreas irrigadas, floresta nativa densa e a Caatinga do Estado do Ceará (Baixo Acaraú, Chapada do Apodi e Chapada do Araripe). Este algoritmo calcula a evapotranspiração horária a partir do fluxo de calor latente, estimado como resíduo do balanço de energia na superfície. Os valores de ET obtidos nas três regiões foram superiores a 0,60 mm h-1 nas áreas irrigadas ou de vegetação nativa densa. As áreas de vegetação nativa menos densa apresentaram taxa da ET horária de 0,35 a 0,60 mm h-1, e valores quase nulos em áreas degradadas. A análise das médias de evapotranspiração horária pelo teste de Tukey a 5% de probabilidade permitiu evidenciar uma variabilidade significativa local, bem como regional no Estado do Ceará.In the context of water resources scarcity, the rational use of water for irrigation is necessary, implying precise estimations of the actual evapotranspiration (ET). With the recent progresses of remote-sensed technologies, regional algorithms estimating evapotranspiration from satellite observations were developed. This work aimed at applying the SEBAL algorithm (Surface Energy Balance Algorithms for Land) at three Landsat-5 images during the second semester of 2006. These images cover irrigated areas, dense native forest areas and caatinga areas in three regions of the state of Ceará (Baixo Acaraú, Chapada do Apodi and Chapada do Araripe). The SEBAL algorithm calculates the hourly evapotranspiration from the latent heat flux, estimated from the surface energy balance. The hourly evapotranspiration values obtained were greater than 0.60 mm h-1 in irrigated or dense native vegetation areas, from 0.35 to 0.60 mm h-1 in sparse vegetation areas and almost null in degradated areas. The analysis of hourly evapotranspiration means by Tukey test at 5% probability level showed not only a significant variability locally but also at a regional scale in the state of Ceará.

O texto justifica a diferenciação por meio dos paradigmas de coerência e integridade, de sistema e sistematicidade no Direito por meio da discussão do papel das antinomias jurídicas. Torna evidente que o pressuposto filosófico de aporética jurídica é ligado ao conceito de correção da lógica deôntica.

Gold and nickel bisdithiolene complexes with methyl and tert-butyl substituted thiophenetetrathiafulavalenedithiolate ligands (α-mtdt and α-tbtdt) were prepared and characterized. These complexes were obtained, under anaerobic conditions, as tetrabutylammonium salts. The diamagnetic gold monoanion (n-Bu4N)[Au(α-mtdt)2] (3) and nickel dianionic species (n-Bu4N)x[Ni(α-mtdt)2] (x = 1,2) (4) were similar to the related non-substituted extended thiophenic-TTF (TTF = tetrathiafulvalene) bisdithiolenes. However the introduction of the large, bulky substituent tert-butyl, led to the formation of a Au (I) dinuclear complex, (n-Bu4N)2[Au2(α-tbtdt)2] (5). The neutral methyl substituted gold and nickel complexes were easily obtained through air or iodine exposure as polycrystalline or amorphous fine powder. [Au(α-mtdt)2] (6) and [Ni(α-mtdt)2] (7) polycrystalline samples display properties of a metallic system with a room temperature electrical conductivity of 0.32 S/cm and ≈4 S/cm and a thermoelectric power of ≈5 µV/K and ≈32 µV/K, respectively. While [Au(α-mtdt)2] (6) presented a Pauli-like magnetic susceptibility typical of conducting systems, in [Ni(α-mtdt)2] (7) large magnetic susceptibilities indicative of high spin states were observed. Both electric transport properties and magnetic properties for gold and nickel [M(α-mtdt)2] are indicative that these compounds are single component molecular conductors.

In recent years, railway systems have played a significant role in transportation systems due to the demand increase in conveying both cargo and passengers. Due to the harsh environments and severe loading conditions, caused by the traffic growth, heavier axles and vehicles and increase in speed, railway tracks are at risk of degradation and failure. Condition monitoring has been widely used to support the health assessment of civil engineering structures and infrastructures. In this context, it was adopted as a powerful tool for an objective assessment of the railway track behaviour by enabling real-time data collection, inspection and detection of structural degradation. According to relevant literature, a number of sensors can be used to monitor track behaviour during the train passing under harsh environments. This paper presents a review of sensors used for structural monitoring of railway track infrastructure, as well as their application to sense the performance of different track components during extreme events. The insight into track monitoring for railways serving traffic with extreme features will not only improve the track inspection and damage detection but also enable a predictive track maintenance regime in order to assist the decision-making process towards more cost-effective management in the railway industry.

Cisplatin is a chemotherapeutic agent whose use is limited by side effects including neuropathies. In proliferating cells, toxic action of cisplatin is based on DNA interactions, while, in quiescent cells, it can induce apoptosis by interacting with proteins. In the present study, we compared cytotoxic mechanisms activated by cisplatin in primate and rodent neurons and in ovary cells in order to determine whether the anti-apoptotic peptide PACAP could selectively reduce neurotoxicity. In quiescent neurons, JNK and sphingomyelinase inhibitors blocked cisplatin-induced cell death. Toxicity was associated with DNA laddering, caspase-3 and -9 activations and Bax induction. These effects were prevented by PACAP. In proliferating cells, cisplatin activated caspase-8 but had no effect on caspase-9. PACAP exerted no protective effect. These data indicate that cisplatin activates distinct apoptotic pathways in quiescent neurons and proliferating cells and that PACAP may reduce neurotoxicity of cisplatin without affecting its chemotherapeutic efficacy.

Background: Both the supplementary motor complex (SMC), consisting of the supplementary motor area (SMA)-proper, the pre-SMA and the supplementary eye field, and the rostral cingulate cortex (ACC) are supplied by the anterior cerebral artery (ACA) and are involved in higher motor control. The Bereitschaftspotential (BP) originates from the SMC and reflects cognitive preparation processes before volitional movements. ACA strokes may lead to impaired motor control in the absence of limb weakness and evoke an alien-hand syndrome (AHS) in its extreme form.Aim: To characterize the clinical spectrum of disturbed motor control after ACA strokes including signs attributable to AHS and to identify the underlying neuroanatomical correlates.Methods: A clinical assessment focusing on signs of disturbed motor control including intermanual conflict (i.e. bilateral hand movements directed at opposite purposes), lack of self-initiated movements, exaggerated grasping, motor perseverations, mirror movements and gait apraxia was performed. Symptoms were grouped into A) AHS specific and B) non-AHS specific signs of upper limbs and C) gait apraxia. Lesion summation mapping was applied to the patients’ MRI or CT scans to reveal associated lesion patterns. The BP was recorded in two patients.Results: Ten patients with ACA strokes (9 unilateral, 1 bilateral; mean age: 74.2 years; median NIH-SS at admission: 13.0) were included in this case series. In the acute stage, all cases had marked difficulties to perform volitional hand movements, while movements in response to external stimuli were preserved. In the chronic stage (median follow-up: 83.5 days) initiation of voluntary movements improved, although all patients showed persistent signs of disturbed motor control. Impaired motor control is predominantly associated with damaged voxels within the SMC and the anterior and medial cingulate cortex, while lesions within the pre-SMA are specifically related to AHS. No BP was detected over the damaged hemisphere.Conclusion: ACA strokes involving the premotor cortices, particularly the pre-SMA, are associated with AHS-specific signs. In the acute phase, motor behaviour is characterized by the inability to carry out self-initiated movements. Motor control deficits may persist to a variable degree beyond the acute phase. Alterations of the BP point to an underlying SMC dysfunction in AHS.

Aim: To describe structural covariance networks of grey matter volume (GMV) change in 28 patients with first-ever stroke to the primary sensorimotor cortices, and to investigate their relationship to hand function recovery and local GMV change.Methods: Tensor based morphometry maps derived from high resolution structural images were subject to principal component analyses to identify the networks. We calculated correlations between network expression and local GMV change, sensorimotor hand function and lesion volume. To verify which of the structural covariance networks of GMV change have a significant relationship to hand function we performed an additional multivariate regression approach.Results: Expression of the second network, explaining 9.1% of variance, correlated with GMV increase in the medio-dorsal (md) thalamus and hand motor skill. Patients with positive expression coefficients were distinguished by significantly higher GMV-increase of this structure during stroke recovery. Significant nodes of this network were located in md thalamus, dorsolateral prefrontal cortex and higher order sensorimotor cortices. Parameter of hand function had a unique relationship to the network and depended on an interaction between network expression and lesion volume. Inversely network expression is limited in patients with large lesion volumes.Conclusions: Chronic phase of sensorimotor cortical stroke has been characterized by a large scale covarying structural network in the ipsilesional hemisphere associated specifically with sensorimotor hand skill. Its expression is related to GMV-increase of md thalamus, one constituent of the network, and correlated with the cortico-striato-thalamic loop involved in control of motor execution and higher order sensorimotor cortices. A close relation between expression of this network with degree of recovery might indicate reduced compensatory resources in the impaired subgroup.

O presente artigo debruça-se sobre a obra historiográfica de Joaquim de Carvalho, um dos maiores vultos da cultura portuguesa, no século XX, procurando individualizar e sistematizar uma apreciação aos seus trabalhos precursores na área específica da História da Ciência, que muito contribuíram para a consolidação dessa área disciplinar em Portugal. Depois de uma breve apresentação biográfica, contendo os principais momentos da sua vivência académica e política, e de uma síntese do conjunto de apreciações críticas à sua obra, estabelecem-se as premissas conceptuais e metodológicas que nortearam a sua investigação, no campo da historiografia da ciência, procurando relevar o carácter inovador das suas abordagens face ao tradicionalismo historiográfico português.

Morbidity and mortality caused by schistosomiasis are serious public health problems in developing countries. Because praziquantel is the only drug in therapeutic use, the risk of drug resistance is a concern. In the search for new schistosomicidal drugs, we performed a target-based chemogenomics screen of a dataset of 2,114 proteins to identify drugs that are approved for clinical use in humans that may be active against multiple life stages of Schistosoma mansoni. Each of these proteins was treated as a potential drug target, and its amino acid sequence was used to interrogate three databases: Therapeutic Target Database (TTD), DrugBank and STITCH. Predicted drug-target interactions were refined using a combination of approaches, including pairwise alignment, conservation state of functional regions and chemical space analysis. To validate our strategy, several drugs previously shown to be active against Schistosoma species were correctly predicted, such as clonazepam, auranofin, nifedipine, and artesunate. We were also able to identify 115 drugs that have not yet been experimentally tested against schistosomes and that require further assessment. Some examples are aprindine, gentamicin, clotrimazole, tetrabenazine, griseofulvin, and cinnarizine. In conclusion, we have developed a systematic and focused computer-aided approach to propose approved drugs that may warrant testing and/or serve as lead compounds for the design of new drugs against schistosomes.

Medicinal chemists continue to be fascinated by chalcone derivatives because of their simple chemistry, ease of hydrogen atom manipulation, straightforward synthesis, and a variety of promising biological activities. However, chalcones have still not garnered deserved attention, especially considering their high potential as chemical sources for designing and developing new effective drugs. In this review, we summarize current methodological developments towards the design and synthesis of new chalcone derivatives and state-of-the-art medicinal chemistry strategies (bioisosterism, molecular hybridization, and pro-drug design). We also highlight the applicability of computer-assisted drug design approaches to chalcones and address how this may contribute to optimizing research outputs and lead to more successful and cost-effective drug discovery endeavors. Lastly, we present successful examples of the use of chalcones and suggest possible solutions to existing limitations.

In human neonates, immature GABAergic interneurons are markedly affected by an excitotoxic insult. While in adults the interest of cell transplantation has been demonstrated in several neurological disorders, few data are available regarding the immature brain. The low survival rate constitutes a strong limitation in the capacity of transplanted neurons to integrate the host tissue. Because i) autophagy is an adaptive process to energetic/nutrient deprivation essential for cell survival and ii) literature describes cross-talks between autophagy and apoptosis, we hypothesized that regulation of autophagy would represent an original strategy to favor long-term survival of GABAergic precursors grafted in the immature neocortex. Morphological, neurochemical, and functional data showed that in control conditions, few grafted Gad67-GFP precursors survived. The first hours following transplantation were a critical period with intense apoptosis. Experiments performed on E15.5 ganglionic eminences revealed that Gad67-GFP precursors were highly sensitive to autophagy. Rapamycin and 3-MA impacted on LC3 cleavage, LC3II translocation, and autophagosome formation. Quantification of Bax, mitochondrial integrity, caspase-3 cleavage, and caspase-3 immunolocalization and activity showed that 3-MA induced a significant decrease of Gad67-GFP precursor apoptosis. In vivo, 3-MA induced, within the first 24 h, a diffuse LC3 pattern of grafted Gad67-GFP precursors, an increase of precursors with neurites, a reduction of the density of caspase-3 immunoreactive cells. A twofold increase in the survival rate occurred 15 days after the graft. Surviving neurons were localized in the cortical layers II–IV, which were still immature when the transplantation was done. Altogether, these data indicate that inhibition of autophagy represents an original strategy to allow GABAergic interneurons to overpass the first critical hours following transplantation and to increase their long-term survival in mice neonates.

O presente texto elucida algumas implicações da escravidão para comprovar a sua caracterização como expressão latente da raiz da questão social no Brasil colônia. Apresentamos, de maneira introdutória, a importância de tal análise para as ciências sociais e asseveramos que a principal característica fundante da questão social no Brasil é a relação senhor-escravo, latente na formação arquitetônica da cidade no Brasil colônia centrada no pelourinho. Neste artigo, abordam-se ainda a formação do povoamento por colonos degradados e as relações do trabalho escravo, a formação econômica baseada no escravismo colonial, a formação do privatismo no Brasil, o Estado na colônia a serviço da escravidão, a formação da ética católica como espírito escravista e a formação política do liberalismo brasileiro: o livre comércio do trabalho escravo.

Autoassociative artificial neural networks have been used in many different computer vision applications. However, it is difficult to define the most suitable neural network architecture because this definition is based on previous knowledge and depends on the problem domain. To address this problem, we propose a constructive autoassociative neural network called CANet (Constructive Autoassociative Neural Network). CANet integrates the concepts of receptive fields and autoassociative memory in a dynamic architecture that changes the configuration of the receptive fields by adding new neurons in the hidden layer, while a pruning algorithm removes neurons from the output layer. Neurons in the CANet output layer present lateral inhibitory connections that improve the recognition rate. Experiments in face recognition and facial expression recognition show that the CANet outperforms other methods presented in the literature.

High concentrations of pituitary adenylate cyclase-activating polypeptide (PACAP) and a high density of PACAP binding sites have been detected in the developing rat cerebellum. In particular, PACAP receptors are actively expressed in immature granule cells, where they activate both adenylyl cyclase and phospholipase C. The aim of the present study was to investigate the ability of PACAP to induce calcium mobilization in cerebellar granule neurons. Administration of PACAP induced a transient, rapid and monophasic rise of the cytosolic calcium concentration ([Ca2+]i), while vasoactive intestinal peptide was devoid of effect, indicating the involvement of the PAC1 receptor in the Ca2+ response. Preincubation of granule cells with the Ca2+ ATPase inhibitor, thapsigargin, or the D-myo-inositol 1,4,5-trisphosphate (IP3) receptor antagonist, 2APB, markedly reduced the stimulatory effect of PACAP on [Ca2+]i. Furthermore, addition of the calcium chelator, EGTA, or exposure of cells to the non-selective Ca2+ channel blocker, NiCl2, significantly attenuated the PACAP-evoked [Ca2+]i increase. Preincubation of granule neurons with the N-type Ca2+ channel blocker, omega-conotoxin GVIA, decreased the PACAP-induced [Ca2+]i response, whereas the L-type Ca2+ channel blocker, nifedipine, and the P- and Q-type Ca2+ channel blocker, omega-conotoxin MVIIC, had no effect. Altogether, these findings indicate that PACAP, acting through PAC1 receptors, provokes an increase in [Ca2+]i in granule neurons, which is mediated by both mobilization of calcium from IP3-sensitive intracellular stores and activation of N-type Ca2+ channel. Some of the activities of PACAP on proliferation, survival, migration and differentiation of cerebellar granule cells could thus be mediated, at least in part, through these intracellular and/or extracellular calcium fluxes.

Hypoxia-ischemia (HI) and excitotoxicity are validated causes of neonatal brain injuries and tissue plasminogen activator (t-PA) participates in the processes through proteolytic and receptor-mediated pathways. Brain microvascular endothelial cells from neonates in culture, contain and release more t-PA and gelatinases upon glutamate challenge than adult cells. We have studied t-PA to gelatinase (MMP-2 and MMP-9) activity links in HI and excitotoxicity lesion models in 5 day-old pups in wild type and in t-PA or its inhibitor (PAI-1) genes inactivated mice. Gelatinolytic activities were detected in SDS-PAGE zymograms and by in situ fluorescent DQ-gelatin microscopic zymographies. HI was achieved by unilateral carotid ligature followed by a 40 min hypoxia (8%O₂). Excitotoxic lesions were produced by intra parenchymal cortical (i.c.) injections of 10 µg ibotenate (Ibo). Gel zymograms in WT cortex revealed progressive extinction of MMP-2 and MMP-9 activities near day 15 or day 8 respectively. MMP-2 expression was the same in all strains while MMP-9 activity was barely detectable in t-PA⁻/⁻ and enhanced in PAI-1⁻/⁻ mice. HI or Ibo produced activation of MMP-2 activities 6 hours post-insult, in cortices of WT mice but not in t-PA⁻/⁻ mice. In PAI-1⁻/⁻ mice, HI or vehicle i.c. injection increased MMP-2 and MMP-9 activities. In situ zymograms using DQ-gelatin revealed vessel associated gelatinolytic activity in lesioned areas in PAI-1⁻/⁻ and in WT mice. In WT brain slices incubated ex vivo, glutamate (200 µM) induced DQ-gelatin activation in vessels. The effect was not detected in t-PA⁻/⁻ mice, but was restored by concomitant exposure to recombinant t-PA (20 µg/mL). In summary, neonatal brain lesion paradigms and ex vivo excitotoxic glutamate evoked t-PA-dependent gelatinases activation in vessels. Both MMP-2 and MMP-9 activities appeared t-PA-dependent. The data suggest that vascular directed protease inhibition may have neuroprotection potential against neonatal brain injuries.

Track-while-scan bird radars are widely used in ornithological studies, but often the precise detection capabilities of these systems are unknown. Quantification of radar performance is essential to avoid observational biases, which requires practical methods for validating a radar's detection capability in specific field settings. In this study a method to quantify the detection capability of a bird radar is presented, as well a demonstration of this method in a case study. By time-referencing line-transect surveys, visually identified birds were automatically linked to individual tracks using their transect crossing time. Detection probabilities were determined as the fraction of the total set of visual observations that could be linked to radar tracks. To avoid ambiguities in assigning radar tracks to visual observations, the observer's accuracy in determining a bird's transect crossing time was taken into account. The accuracy was determined by examining the effect of a time lag applied to the visual observations on the number of matches found with radar tracks. Effects of flight altitude, distance, surface substrate and species size on the detection probability by the radar were quantified in a marine intertidal study area. Detection probability varied strongly with all these factors, as well as species-specific flight behaviour. The effective detection range for single birds flying at low altitude for an X-band marine radar based system was estimated at ~1.5 km. Within this range the fraction of individual flying birds that were detected by the radar was 0.50 ± 0.06 with a detection bias towards higher flight altitudes, larger birds and high tide situations. Besides radar validation, which we consider essential when quantification of bird numbers is important, our method of linking radar tracks to ground-truthed field observations can facilitate species-specific studies using surveillance radars. The methodology may prove equally useful for optimising tracking algorithms.