Real-world applications have been dealing with large amounts of data that arrive over time and generally present changes in their underlying joint probability distribution, i.e., concept drift. ...Concept drift can be subdivided into two types: virtual drift, which affects the unconditional probability distribution <inline-formula><tex-math notation="LaTeX">p(\boldsymbol{x})</tex-math> <mml:math><mml:mrow><mml:mi>p</mml:mi><mml:mo>(</mml:mo><mml:mi mathvariant="bold">x</mml:mi><mml:mo>)</mml:mo></mml:mrow></mml:math><inline-graphic xlink:href="oliveira-ieq1-3099690.gif"/> </inline-formula>, and real drift, which affects the conditional probability distribution <inline-formula><tex-math notation="LaTeX">p(y|\boldsymbol{x})</tex-math> <mml:math><mml:mrow><mml:mi>p</mml:mi><mml:mo>(</mml:mo><mml:mi>y</mml:mi><mml:mo>|</mml:mo><mml:mi mathvariant="bold">x</mml:mi><mml:mo>)</mml:mo></mml:mrow></mml:math><inline-graphic xlink:href="oliveira-ieq2-3099690.gif"/> </inline-formula>. Existing work focuses on real drift. However, strategies to cope with real drift may not be the best suited for dealing with virtual drift, since the real class boundaries remain unchanged. We provide the first in depth analysis of the differences between the impact of virtual and real drifts on classifiers' suitability. We propose an approach to handle both drifts called On-line Gaussian Mixture Model With Noise Filter For Handling Virtual and Real Concept Drifts (OGMMF-VRD). Experiments with seven synthetics and seven real-world datasets show that OGMMF-VRD outperforms other approaches with separate mechanisms to deal with virtual and real drifts. It also has more stable rankings and smaller drops in performance during drifting periods than existing ensemble approaches, thus, being more reliable for adoption in practice.
This study describes the use of electrochemical paper-based analytical devices (ePADs) drawn with graphite pencil for the determination of ascorbic acid (AA) in commercial tablets. ePADs were ...fabricated using vegetal paper and graphite pencil. First, the three-electrode electrochemical cell drawn using a graphical software and toner lines were laser printed on the vegetal paper surface to delimit the electrode areas. Then, the electrode regions were manually painted with graphite pencil. Afterwards, the pseudo-reference electrode was defined with the deposition of silver ink over the graphite surface. Cyclic voltammetry and square wave voltammetry (SWV) experiments were performed to optimize the electroanalytical parameters as well as to quantitatively determine the AA concentration in two commercial tables. ePADs exhibited linear behavior for a concentration range between 0.5 and 3.0 mmol L−1. The achieved limit of detection and sensitivity were 70 μmol L−1 and 0.47 μA/mmol L−1, respectively. The AA concentration levels found by SWV experiments in both CenevitTM and Energil CTM were 2.80 ± 0.02 and 3.10 ± 0.01 mmol L−1, respectively. The accuracy of the proposed devices was investigated through recovery experiments in three concentration levels and it presented values between 95 and 115%.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract Objective The aim of this cross-sectional study was to assess the potential relationships between fruit and vegetable (FV) intake and oxidative stress markers in middle-aged men, with an ...emphasis on vitamin C, fiber, and magnesium content. Methods The study was conducted with 296 healthy men, age 50.5 ± 5.0 y, and body mass index (BMI) of 25.8 ± 3.5 kg/m2 . Dietary intake, anthropometry, blood pressure, lifestyle features, and blood and urine biochemical data were assessed with validated procedures. The oxidative stress markers selected were plasma oxidized low-density lipoprotein (ox-LDL), urinary 8-iso-prostaglandin F2 α (8-iso-PGF2 α) and 8-hydroxy-2′-deoxyguanosine (8-OHdG). Results The men included in the highest tertile of FV intake (≥341.1 g/d) displayed lower concentrations of ox-LDL, 8-iso-PGF2 α and 8-OHdG ( P for trend < 0.05), regardless of confounding factors. Concentrations of ox-LDL were negatively associated with fiber from the FV intake ( P for trend < 0.05) regardless of confounding factors. ox-LDL and 8-OHdG concentrations tended to be lower in the higher tertile of magnesium ( P for trend = 0.06) and vitamin C from FV intake ( P for trend = 0.05), respectively. Additionally, concentrations of 8-iso-PGF2 α were lower in men in the highest tertile of fiber (≥6.5 g/d; P for trend = 0.034), vitamin C (≥98.0 mg/d; P for trend = 0.007), and magnesium (≥48.9 mg/d; P for trend = 0.018) from the FV-group intake. Conclusions Greater FV intake was independently associated with reduced ox-LDL, 8-OHdG, and 8-iso-PGF2 α in middle-aged men. Fiber, vitamin C, and magnesium from FV seem to contribute to this beneficial relationship.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract
Droughts are predicted to increase in both frequency and intensity by the end of the 21st century, but ecosystem response is not expected to be uniform across landscapes. Here we assess the ...importance of the hill-to-valley hydrologic gradient in shaping vegetation embolism resistance under different rainfall regimes using hydraulic functional traits. We demonstrate that rainfall and hydrology modulate together the embolism resistance of tree species in different sites and topographic positions. Although buffered by stable access to groundwater, valley plants are intrinsically more vulnerable to drought-induced embolism than those on hills. In all study sites, the variability in resistance to embolism is higher on hills than on valleys, suggesting that the diversity of strategies to cope with drought is more important for tree communities on hills. When comparing our results with previously published data across the tropics, we show greater variability at the local scale than previously reported. Our results reinforce the urgent need to extend sampling efforts across rainfall regimes and topographic positions to improve the characterization of ecosystem resistance to drought at finer spatial scales.
Dengue virus (DENV) is an arbovirus that belongs to the Flaviviridae family. Studies reveal that peptides secreted by amphibians have many functions, such as antiviral and antimicrobial activities. ...As there is no antiviral drug effective against the DENV, the antiviral activity of a synthetic peptide called HS-1, derived from the secretion of the anuran Hypsiboas semilineatus, has been evaluated. The assays of neutralization in the Vero cells show a complete inhibition of infection of the serotypes 2 and 3. Furthermore, the direct action of peptides on the viral particle can be observed through atomic force microscopy. In vivo tests display 80% protection against the dengue-2 virus due to the presence of HS-1, which reveals its potential as an antiviral against the DENV.
•The use of antimicrobial peptides (AMPs) as antivirals has increased in recent times and has shown promise.•Many molecules have been described as being able to inhibit viral replication, such as, analogs of defensins, dermaseptins, and latarcins.•On account of the lack of a vaccine and treatment against the dengue virus, it has been considered necessary to test antivirals against the dengue virus.•The results are promising against dengue-2 and dengue-3 and the antivirals tested have shown efficiency in both in vitro and in vivo experiments, in which the antiviral appears to act directly on the viral particle, disrupting the lipoprotein envelope.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study used a murine model of Chagas disease to investigate the isolated and combined impact of Trypanosoma cruzi infection and benznidazole (BZ) therapy on liver structure and function. Male ...C57BL/6 mice were challenged with T. cruzi and BZ for 15 days. Serum levels of cytokines and hepatic enzymes, liver oxidative stress, morphology, collagen, and glycogen content were monitored. Separately, T. cruzi infection and BZ treatment resulted in a pro-oxidant status and hepatic reactive damage. Concurrently, both T. cruzi infection and BZ treatment induced upregulation of antioxidant enzymes and pathological reorganization of the liver parenchyma and stroma. T. cruzi infection increased serum levels of Th1 cytokines, which were reduced by BZ in both infected and non-infected animals. BZ also induced functional organ damage, increasing serum levels of liver enzymes. When combined, T. cruzi infection and BZ therapy elicited intense hepatic reactive damage that was not compensated by antioxidant enzymatic reaction, subsequently culminating in more severe morphofunctional hepatic injury. Taken together, these findings indicate that during specific treatment of Chagas disease, hepatic pathology may be a result of an interaction between BZ metabolism and specific mechanisms activated during the natural course of T. cruzi infection, rather than an isolated toxic effect of BZ on liver structure and function.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Just-in-Time Software Defect Prediction (JIT-SDP) operates in an online scenario where additional training data is received over time. Existing online JIT-SDP studies used online Oza ensemble ...learning methods with Hoeffding Trees as base learners to learn and update JIT-SDP models over time in this scenario. However, it is unknown how these approaches compare against offline learning approaches adapted to operate in online scenarios, and how the use of any other online or offline base learners would affect online JIT-SDP in terms of predictive performance and computational cost. We therefore propose a new approach called Batch Oversampling Rate Boosting (BORB) that is able to use offline base learners in an online JIT-SDP scenario. Based on 10 open source projects, we provide a comprehensive evaluation of BORB with 5 different base learners and the existing online approach Oversampling Rate Boosting with 4 different base learners, both in within-project and cross-project online JIT-SDP scenarios. The results show that offline learning can lead to better predictive performance than the top performing online learning approaches considered in our study, at a higher computational cost. Cross-project data was helpful to improve predictive performance both for offline and online learning, but especially for online learning.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
This study aimed to investigate the effects of diets with and without antibiotics supplementation and diets with 18.5% and 13.0% crude protein (CP) on growth performance, carcass ...characteristics, disease incidence, fecal microbiota, immune response, and antioxidant capacity of growing pigs. One hundred and eighty pigs (59-day-old; 18.5 ± 2.5 kg) were distributed in a randomized complete block design in a 2 × 2 factorial arrangement, nine replicates, and five pigs per pen. The factors were CP (18.5% or 13.0%) and antibiotics (none or 100 mg/kg tiamulin + 506 mg/kg oxytetracycline). Medicated diets were fed from days 59 to 73. After that, all pigs were fed their respective CP diets from 73 to 87 days. Data were analyzed using the Mixed procedure in SAS version 9.4. From days 59 to 73, pigs fed antibiotics diets had higher (P < 0.05) average daily feed intake (ADFI), average daily weight gain (ADG), gain to feed ratio (G:F), compared to the diets without antibiotics. From days 73 to 87 (postmedicated period), any previous supplementation of antibiotics did not affect pig growth performance. Overall (days 59 to 87), pigs-fed antibiotics diets had higher (P < 0.05) G:F compared to pigs-fed diets without antibiotics. In all periods evaluated, pigs fed 18.5% CP diets had higher (P < 0.05) ADG and G:F compared to pigs fed 13.0% CP. Pigs fed the 13.0% CP diets had lower (P < 0.05) fecal score and diarrhea incidence than those fed 18.5% CP. Pigs fed 18.5% CP diets had improved (P < 0.05) loin area compared to pigs-fed diets with 13.0% CP. At 66 days of age, pigs-fed antibiotics diets had lower (P < 0.05) alpha diversity estimated with Shannon and Simpson compared to the pig-fed diets without antibiotics. At family level, pigs fed 18.5% CP diets had higher (P < 0.05) relative abundance of Streptococcaceae, and lower (P < 0.05) relative abundance of Clostridiaceae at days 66 and 87 compared with pigs fed 13.0% CP. Pigs-fed antibiotics diets had lower (P < 0.05) immunoglobulin G and protein carbonyl concentrations at day 66 compared to the pigs-fed diets without antibiotics. The reduction of dietary CP from 18.5% to 13.0% reduced the growth performance and loin muscle area of growing pigs, although it was effective to reduce diarrhea incidence. Antibiotics improved growth performance, lowered diarrhea incidence, improved components of the humoral immune response, and reduced microbiota diversity. However, in the postmedicated period, we found no residual effect on the general health of the animals, and considering the overall period, only G:F was improved by the use of antibiotics.
The reduction of dietary crude protein from 18.5% to 13.0% reduces the growth performance of growing pigs, although it was effective to reduce diarrhea incidence. Antibiotics improved growth performance and health of animals; however, during the postmedicated period, only gain to feed ratio was improved by the use of antibiotics.
Lay Summary
Dietary antibiotics have been used in pig farming practices to avoid health problems and improve animal growth performance. However, their use in production animals is considered a global health challenge, due to its association with selection of resistance in zoonotic bacteria. Another negative impact of pig farming that has gained attention is related to environmental pollution due to the excretion of nitrogenous compounds. Reducing dietary crude protein content has become a goal in the pig feed industry due to the limited availability and high cost of dietary protein sources, as well as the aim of enhancing gut health in pigs. Thus, the aim of this study was to investigate the effects of diets with and without antibiotics supplementation and diets with 18.5% and 13.0% crude protein for pigs. The reduction of dietary crude protein in this study reduced growth performance, although it was effective to reduce diarrhea incidence. Antibiotics improved growth performance, positively affected the overall health of animals, and reduced microbiota diversity. However, during the postmedicated period, we found no residual effect on the general health of the animals, and considering the overall period, only gain to feed ratio was improved by the use of antibiotics.
The cryptocurrency market has grown significantly, and this quick growth has given rise to scams. It is necessary to put fraud detection mechanisms in place. The challenge of inadequate labeling is ...addressed in this work, which is a barrier to the training of high-performance supervised classifiers. It aims to lessen the necessity for laborious and time-consuming manual labeling. Some unlabeled data points have labels that are more pertinent and informative for the supervised model to learn from. The viability of utilizing unsupervised anomaly detection algorithms and active learning strategies to build an iterative process of acquiring labeled transactions in a cold start scenario, where there are no initial-labeled transactions, is being investigated. Investigating anomaly detection capabilities for a subset of data that maximizes supervised models’ learning potential is the goal. The anomaly detection algorithms under performed, according to the results. The findings underscore the need that anomaly detection algorithms be reserved for situations involving cold starts. As a result, using active learning techniques would produce better outcomes and supervised machine learning model performance.
Finding novel methodologies that enhance the precision, agility, and standardization of drug discovery is crucial for studying leishmaniasis. The slide count is the technique most used to assess the ...leishmanicidal effect of a given drug in vitro. Despite being consolidated in the scientific environment, it presents several difficulties in its execution, assessment, and results. In addition to being laborious, this technique takes time, both for the preparation of the material for analysis and for the counting itself. Our research group suggests a fresh approach to address this requirement, which involves utilizing nuclear labeling with propidium iodide and flow cytometry to determine the quantity of Leishmania sp. parasites present in macrophages in vitro. Our results show that the fluorescence of infected samples increases as the infection rate increases. Using Pearson's Correlation analysis, it was possible to establish a correlation coefficient (Pearson r = 0.9473) that was strongly positive, linear, and directly proportional to the fluorescence and infection rate variables. Thus, it is possible to infer a mathematical equation through linear regression to estimate the number of parasites in each sample using the Relative Fluorescence Units (RFU) values. This new methodology opens space for the possibility of using this methodological resource in the in vitro quantification of Leishmania in macrophages.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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