1,227 research outputs found
Beyond Mahalanobis-Based Scores for Textual OOD Detection
Deep learning methods have boosted the adoption of NLP systems in real-life
applications. However, they turn out to be vulnerable to distribution shifts
over time which may cause severe dysfunctions in production systems, urging
practitioners to develop tools to detect out-of-distribution (OOD) samples
through the lens of the neural network. In this paper, we introduce TRUSTED, a
new OOD detector for classifiers based on Transformer architectures that meets
operational requirements: it is unsupervised and fast to compute. The
efficiency of TRUSTED relies on the fruitful idea that all hidden layers carry
relevant information to detect OOD examples. Based on this, for a given input,
TRUSTED consists in (i) aggregating this information and (ii) computing a
similarity score by exploiting the training distribution, leveraging the
powerful concept of data depth. Our extensive numerical experiments involve 51k
model configurations, including various checkpoints, seeds, and datasets, and
demonstrate that TRUSTED achieves state-of-the-art performances. In particular,
it improves previous AUROC over 3 points
HIPE: HMC Instruction Predication Extension Applied on Database Processing
The recent Hybrid Memory Cube (HMC) is a smart memory which includes functional units inside one logic layer of the 3D stacked memory design. In order to execute instructions inside the Hybrid Memory Cube (HMC), the processor needs to send instructions to be executed near data, keeping most of the pipeline complexity inside the processor. Thus, control-flow and data-flow dependencies are all managed inside the processor, in such way that only update instructions are supported by the HMC. In order to solve data-flow dependencies inside the memory, previous work proposed HMC Instruction Vector Extensions (HIVE), which embeds a high number of functional units with a interlock register bank. In this work we propose HMC Instruction Prediction Extensions (HIPE), that supports predicated execution inside the memory, in order to transform control-flow dependencies into data-flow dependencies. Our mechanism focus on removing the high latency iteration between the processor and the smart memory during the execution of branches that depends on data processed inside the memory. In this paper we evaluate a balanced design of HIVE comparing to x86 and HMC executions. After we show the HIPE mechanism results when executing a database workload, which is a strong candidate to use smart memories. We show interesting trade-offs of performance when comparing our mechanism to previous work
Arginine methylation analysis of the splicing-associated SR protein SFRS9/SRP30C
The human SFRS9/SRp30c belongs to the SR family of splicing regulators. Despite evidence that members of this protein family may be targeted by arginine methylation, this has yet to be experimentally addressed. In this study, we found that SFRS9 is a target for PRMT1-mediated arginine methylation in vitro, and that it is immunoprecipitated from HEK-293 lysates by antibodies that recognize both mono- and dimethylated arginines. We further observed that upon treatment with the methylation inhibitor Adox, the fluorescent EGFP-SFRS9 re-localizes to dot-like structures in the cell nucleus. In subsequent confocal analyses, we found that EGFP-SFRS9 localizes to nucleoli in Adox-treated cells. Our findings indicate the importance of arginine methylation for the subnuclear localization of SFRS9144657669CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informaçã
The first observed stellar occultations by the irregular satellite Phoebe (Saturn IX) and improved rotational period
peer reviewedWe report six stellar occultations by Phoebe (Saturn IX), an irregular satellite of Saturn, obtained between mid-2017 and mid-2019. The 2017 July 6 event was the first stellar occultation by an irregular satellite ever observed. The occultation chords were compared to a 3D shape model of the satellite obtained from Cassini observations. The rotation period available in the literature led to a sub-observer point at the moment of the observed occultations where the chords could not fit the 3D model. A procedure was developed to identify the correct sub-observer longitude. It allowed us to obtain the rotation period with improved precision compared to the currently known value from literature. We show that the difference between the observed and the predicted sub-observer longitude suggests two possible solutions for the rotation period. By comparing these values with recently observed rotational light curves and single- chord stellar occultations, we can identify the best solution for Phoebe's rotational period as 9.27365 ± 0.00002 h. From the stellar occultations, we also obtained six geocentric astrometric positions in the ICRS as realized by the Gaia DR2 with uncertainties at the 1-mas level
Structure, electronic properties, morphology evolution, and photocatalytic activity in PbMoO4 and Pb12xCaxSrxMoO4 (x = 0.1, 0.2, 0.3, 0.4 and 0.5) solid solutions
In this work PbMoO4 and Pb12xCaxSrxMoO4 (x = 0.1, 0.2, 0.3, 0.4 and 0.5) solid solutions have been
successfully prepared, for the first time, by a simple co-precipitation method and the as-synthesized
samples were subjected to a water-based reflux treatment. Structural characterization of these samples
was performed using X-ray diffraction with Rietveld refinement analysis and Raman spectroscopy. Their
optical properties were investigated by UV-Vis absorption spectroscopy and PL emissions, and the
photocatalytic activity of the as-synthesized samples for the degradation process of Rhodamine B has
been demonstrated. The surface structure and morphologies were characterized by field emission
scanning electron microscopy. To complement and rationalize the experimental results, the geometry,
electronic structures, and morphologies of as-synthesized samples were characterized by first-principles
quantum-mechanical calculations at the density functional theory level. By using Wulff construction,
based on the values of the surface energies for the (001), (100), (110), (111), (011) and (112) surfaces, a
complete map of the available morphologies for PbMoO4 was obtained and a good agreement between
the experimental and theoretical predicted morphologies was found. The structural and electronic
changes induced by the substitution of Pb by Ca and Sr allow us to find a relationship among
morphology, the electron-transfer process at the exposed surfaces, optical properties, and
photocatalytic activity. We believe that our results offer new insights regarding the local coordination of
superficial Pb/Ca/Sr and Mo cations (i.e., clusters) on each exposed surface of the corresponding
morphology, which dictate the photocatalytic activities of the as-synthesized samples, a field that has
so far remained unexplored. The present study, which combines multiple experimental methods and
first-principles calculations, provides a deep understanding of the local structures, bonding,
morphologies, band gaps, and electronic and optical properties, and opens the door to exploit the
electrical, optical and photocatalytic activity of this very promising family of materials
Characterization of growth and metabolism of the haloalkaliphile Natronomonas pharaonis
Natronomonas pharaonis is an archaeon adapted to two extreme conditions: high salt concentration and alkaline pH. It has become one of the model organisms for the study of extremophilic life. Here, we present a genome-scale, manually curated metabolic reconstruction for the microorganism. The reconstruction itself represents a knowledge base of the haloalkaliphile's metabolism and, as such, would greatly assist further investigations on archaeal pathways. In addition, we experimentally determined several parameters relevant to growth, including a characterization of the biomass composition and a quantification of carbon and oxygen consumption. Using the metabolic reconstruction and the experimental data, we formulated a constraints-based model which we used to analyze the behavior of the archaeon when grown on a single carbon source. Results of the analysis include the finding that Natronomonas pharaonis, when grown aerobically on acetate, uses a carbon to oxygen consumption ratio that is theoretically near-optimal with respect to growth and energy production. This supports the hypothesis that, under simple conditions, the microorganism optimizes its metabolism with respect to the two objectives. We also found that the archaeon has a very low carbon efficiency of only about 35%. This inefficiency is probably due to a very low P/O ratio as well as to the other difficulties posed by its extreme environment
Comparação da Radiação Solar Global Incidente Obtida por Diferentes Fontes de Dados para o Norte de SP
O objetivo deste trabalho foi comparar os dados de radiaçãosolar global incidente de três torres micrometeorológicas localizados naregião norte do estado de São Paulo, com os dados disponíveis de outrasfontes: estações meteorológicas de superfície mais próximas e estimativasa partir de satélites (modelo GL1.2). A regressão linear entre as estimativasde radiação do modelo GL1.2 com as observações na área decerrado indicou um ajuste melhor do que o obtido com a estaçãometeorológica mais próxima. Esses resultados sugerem que as estimativasde radiação do modelo GL1.2 podem ser usadas para o preenchimentode falhas de Ki medida nas torres micrometeorológicas e potencialmentecomo forçante em esquemas de superfície e modelos hidrológicosaplicados a bacias hidrográficas da região
Osteopenia and osteoporosis in people living with HIV: multiprofessional approach
Increasing bone mineralization abnormalities observed among people living with HIV (PLWHIV) result from various factors relating to the host, the virus, and the antiretrovirals used. Today, HIV infection is considered to be a risk factor for bone mineralization disorders. The test most recommended for diagnosing osteoporosis is measurement of bone mineral density by means of dual energy X-ray absorptiometry at two sites. Osteoporosis treatment has the aims of bone mass improvement and fracture control. A combination of calcium and vitamin D supplementation may reduce the risk of fractures. Antiresorptive drugs act by blocking osteoclastic activity and reducing bone remodeling. On the other hand, bone-forming drugs stimulate osteoblastogenesis, thereby stimulating the formation of bone matrix. Mixed-action medications are those that are capable of both stimulating bone formation and inhibiting reabsorption. Antiresorptive drugs form the group of medications with the greatest quantity of scientific evidence confirming their efficacy in osteoporosis treatment. Physical activity is a health promotion strategy for the general population, but only preliminary data on its real value and benefit among PLWHIV are available, especially in relation to osteoporosis
Pre-clinical assessment of Roflumilast therapy in a thoracic model of spinal cord injury
The failure of axons to regenerate after a spinal cord injury (SCI) remains one of the greatest challenges in neuroscience. The initial mechanical trauma is followed by a secondary injury cascade, creating a hostile microenvironment, which not only is not permissive to regeneration but also leads to further damage. One of the most promising approaches for promoting axonal regeneration is to maintain the levels of cyclic adenosine monophosphate (cAMP), specifically by a phosphodiesterase-4 (PDE4) inhibitor expressed in neural tissues. Therefore, in our study, we evaluated the therapeutic effect of an FDA-approved PDE4 inhibitor, Roflumilast (Rof), in a thoracic contusion rat model. Results indicate that the treatment was effective in promoting functional recovery. Rof-treated animals showed improvements in both gross and fine motor function. Eight weeks post-injury, the animals significantly recovered by achieving occasional weight-supported plantar steps. Histological assessment revealed a significant decrease in cavity size, less reactive microglia, as well as higher axonal regeneration in treated animals. Molecular analysis revealed that IL-10 and IL-13 levels, as well as VEGF, were increased in the serum of Rof-treated animals. Overall, Roflumilast promotes functional recovery and supports neuroregeneration in a severe thoracic contusion injury model and may be important in SCI treatment.This research was supported by Prémios Santa Casa Neurociências—Prize Melo e Castro
for Spinal Cord Injury Research (MC-18-2021) and by national funds, through the Foundation for
Science and Technology (FCT)—project PTDC/MED-FAR/29751/2017, project UIDB/50026/2020
and UIDP/50026/2020.We would like to acknowledge the financial support by the Foundation for Science
and Technology to the following authors: RL (PD/BDE/127836/2016), JRC (SFRH/BD/145860/2019)
and NAS (CEECIND/04794/2007). We would like to acknowledge the support of the ICVS Scien tific Microscopy Platform, members of the national infrastructure PPBI—Portuguese Platform of
Bioimaging (PPBI-POCI-01-0145-FEDER-022122)
SORPTION OF S-TRIAZINES IN BRAZILIAN RAINFOREST SOILS
This research was conducted to evaluate the sorption of Ametryn, Atrazine, Simazine, Prometrine and Metamitron to soils from "Mata Atlântica" at Ubatuba region (Atlantic rainforest soils), employing the batch equilibrium approach. The herbicides were weakly retained in soils with low soil organic matter (SOM) content and thus presenting high potential to water contamination. All herbicides have shown high Koc at Typic Humaquepts soil, the higher in SOM content. The sorption isotherms for the herbicides at Typic Humaquepts soil suggested specific interactions between herbicides and SOM probably with partial protonation of herbicides followed by ion-exchange processes and/or hydrogen bonding formation of hydroxyl groups on the SOM surface.Esta pesquisa foi conduzida para avaliar a sorção de ametrina, atrazina, simazina, prometrina e metamitron em solos de Mata Atlântica na região de Ubatuba, empregando-se o método em batelada. Os herbicidas foram fracamente retidos em solos com baixo teor de matéria orgânica (MO) e, portanto, apresentaram elevado potencial de contaminação da água. Todos os herbicidas mostraram alto valor de Koc em solos da classe Gleissolo Melânico Distrófico, que contém o teor mais elevado de MO. As isotermas de sorção dos herbicidas no Gleissolo Melânico Distrófico sugerem interações específicas entre os herbicidas e a MO, provavelmente com protonação parcial dos herbicidas seguida por processos de troca-iônica e/ou formação de pontes de hidrogênio dos grupos hidroxila sobre a superfície da MO
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