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There are many claims that gamification (i.e., using game elements outside games) impact decreases over time (i.e., the novelty effect). Most studies analyzing this effect focused on extrinsic game elements, while fictional and collaborative competition have been recently recommended. Additionally, to the best of our knowledge, no long-term research has been carried out with STEM learners from introductory programming courses (CS1), a context that demands encouraging practice and mitigating motivation throughout the semester. Therefore, the main goal of this work is to better understand how the impact of a gamification design, featuring fictional and competitive-collaborative elements, changes over a 14-week period of time, when applied to CS1 courses taken by STEM students (N = 756). In an ecological setting, we followed a 2x7 quasi-experimental design, where Brazilian STEM students completed assignments in either a gamified or non-gamified version of the same system, which provided the measures (number of attempts, usage time, and system access) to assess user behavior at seven points in time. Results indicate changes in gamification's impact that appear to follow a U-shaped pattern. Supporting the novelty effect, the gamification's effect started to decrease after four weeks, decrease that lasted between two to six weeks. Interestingly, the gamification's impact shifted to an uptrend between six and 10 weeks after the start of the intervention, partially recovering its contribution naturally. Thus, we found empirical evidence supporting that gamification likely suffers from the novelty effect, but also benefits from the familiarization effect, which contributes to an overall positive impact on students. These findings may provide some guidelines to inform practitioners about how long the initial contributions of gamification last, and how long they take to recover after some reduction in benefits. It can also help researchers to realize when to apply/evaluate interventions that use gamification by taking into consideration the novelty effect and, thereby, better understand the real impact of gamification on students' behavior in the long run.

The bush dog Speothos venaticus is a medium-sized Neotropical canid. It is considered to be rare and its biology and population parameters are still poorly understood. The Amazon is one of the main strongholds of this species and is important for maintaining viable populations, as the region still holds extensive tracts of pristine habitat. We gathered field data from camera-trap studies throughout the Brazilian Amazon to estimate the relative abundance of the species and gain an understanding of its rarity, and how this compares with estimates from other vegetative formations and for sympatric hypercarnivores. We focused on three pristine or partially disturbed sites and one fragmented site. The estimated relative abundance of the species was 0.060–0.185 individuals per 100 trap-days, confirming that the species is rare. The bush dog's abundance in the Amazon is equivalent to that in all other areas outside the Basin. The mean group size recorded was c. 2.5 individuals. There were no differences in group sizes between forests in the Amazon and in other regions of Central America; however, there were significant differences between forests and open habitats. A combination of competition/predation, habitat structure/integrity, and disease may be acting synergistically in determining the abundance and rarity of bush dogs. [ABSTRACT FROM PUBLISHER]

The article focuses on the geographic distribution and first record of chiroptera species Lampronycteris brachyotis in Acre, Brazil. It notes that the species is easily determined through its yellowish-orange to reddish fur on its throat and upper chest. It is characterized by its omnivore habits including fruits, pollen, insects, and nectar in its diet. It points out that its third metacarpal is longer than the fourth and the fifth. A chart depicting the external measurements of the species from Fazenda Experimental Catuaba and from additional localities in the neotropical region is also presented.

Over the past decade, electric power systems have been restructured based on different models to introduce competition among market participants. Transmission open access for suppliers and customers is one of the most prevailing unbundling services. Usually, a connection tariff is established based on different market factors, including the actual usage of the transmission network. In Brazil, most vertically integrated companies owned by the federal and state governments were unbundled, and new transmission companies are being created. These companies make their assets available to the independent system operator, designated as Operador Nacional do Sistema Elétrico (ONS). One of the main objectives of ONS is to manage transmission services, over a certain voltage level, to ensure nondiscriminatory access to the grid. All transmission users, including regional distribution companies, pay wheeling transmission charges at each delivery or connection point with the major Brazilian network administrated by ONS. This paper presents a methodology for determining the optimal amount of transmission system usage (ATSU) that must be contracted by a regional distribution company, at each connection point. In the proposed approach, the maximum flow at each connection is represented as a random variable in order to obtain the distribution probability of the transmission charges as a function of the ATSU parameter. Besides providing the optimal amounts to be contracted, the proposed probabilistic methodology allows quantifying the risks of violation of each contract and estimating possible penalties. All methodology development steps are described and illustrated through numerical examples. An application to a typical Brazilian regional distribution company is also discussed. [ABSTRACT FROM AUTHOR]

Miconia albicans (Sw.) Triana has been widely used in Brazilian popular medicine for the treatment of several diseases. Aerial parts are used as an infusion to treat arthrosis and arthritis, to relieve rheumatic and stomach pains, and intestinal disorders due to its anti-inflammatory, anti-mutagenic anti-nociceptive, digestive and hepatoprotective properties. This study aimed to characterize the of M. albicans (Sw.) Triana fruits extract (MAFRE) chemical profile and to evaluate its antioxidant, anti-inflammatory and antitumor activities, as well as its toxicity. Maceration with methanol as liquid extractor was used to prepare MAFRE. M. albicans (Sw.) Triana fruits chemical composition was characterized by UHPLC-QTOF-MS/MS and GC-FID (fatty acid methyl esters composition from lyophilized fruits). MAFRE antioxidant potential was evaluated in vitro using a combination of assays: Folin-Ciocalteu reducing capacity, DPPH• and ABTS radical scavenging ability and ferric reducing antioxidant power (FRAP). In vitro antiproliferative activity was investigated in four human tumor cell lines (U251, 786-0, HT29 and MDA-MB-231) while the effect on the non-tumor cell viability was assessed in the VERO cell line using the on-step MTT assay. In addition, in vivo anti-inflammatory effect was assessed by Croton oil-induced ear edema in mice followed by myeloperoxidase (MPO) activity evaluation. Thirty-five compounds were identified by UHPLC-QTOF-MS/MS. Among it flavonoids derived from quercetin (8), myricetin (1), kaempferol (2), terpenoids (6) and other compounds (18). GC-FID analysis identified and quantified nine fatty acids: palmitic, stearic, arachidic, behenic, elaidic, oleic, eicosenoic, and linoleic acids. The most abundant fatty acids were polyunsaturated fatty acids (5.33 ± 0.17 mg g-1), followed by saturated fatty acids (2.38 ± 0.07 mg g-1) and monounsaturated fatty acids (1.74 ± 0.09 mg g-1). The extract revealed high content of phenolic compounds (43.68 ± 0.50 mg GAE/g of extract), potent antioxidant, and ferrous chelating capacities. Morever, it proved to be non-toxic to the VERO cells, not affecting cells viability (95% of viable cells). No antiproliferative effect against human tumor cell lines were found. Furthermore , MAFRE significantly (p<0.05) reduced ear edema (≈35%) and MPO activity (84.5%) having a statistical effect similar to traditional steroidal and non-steroidal anti-inflammatory drugs. Taken together, the results evidenced that M. albicans fruit extract has antioxidant properties, a higher concentration of phenolic compounds, flavonoids, fatty acids, and also topical anti-inflammatory activity with low toxicity of extract on VERO cells. Through the ethnomedicinal study, these findings supporting the popular use of M. albicans , but also highlight that not only aerial parts and leaves deserve attention, but the fruits also have anti-inflammatory proprieties and can be a source of phenolic compounds and other substances with potential health benefices. [Display omitted] • M. albicans fruits extract provided several biologically active compounds, especially flavonoids and terpenoids. • M. albicans fruits have an antioxidant potential superior to other common fruits. • M. albicans fruits proved to be non-toxic to Vero cell line, also has an anti-inflammatory effect in vivo in mice tests. [ABSTRACT FROM AUTHOR]

Phytochemical study of Machaerium brasiliense leaves extract afforded three hopane triterpenes 3,4-seco-21β-H-hop-22 (29)-en-3-oic acid (1), hopenone B (2), hopene B (3). In addition, lupeol (4), stigmasterol (5), β-sitosterol (6), daucosterol (7), uracil (8), allantoin (9) and trans -4-hydroxy- N -methylproline (10) were isolated. The structures of these compounds were established based on spectroscopic data in comparison to those described in literature. Considering the chemotaxonomic relevance of the isolated compounds, this is the first report of triterpenes 1 , 2 and 3 in Fabaceae family and compounds 7 , 8 and 9 in the genus Machaerium. Besides, preliminary screening on antiproliferative and antioxidant activities was performed for MBEB and its fractions. Image 1 • Around 50 species of Machaerium genus (Fabaceae) are endemic in Brazil. • This is the first report on chemical composition of Machaerium brasiliense leaves. • First report of daucosterol, uracil and allantoin in Machaerium genus. • First report of three hopane triterpenes in Fabaceae family. • Low polar M. brasiliense fractions showed cytostatic effect might due to steroids. [ABSTRACT FROM AUTHOR]

Bats are ancient hosts of Trypanosoma species and their flying ability, longevity and adaptability to distinct environments indicate that they are efficient dispersers of parasites. Bats from Acre state (Amazon Biome) were collected in four expeditions conducted in an urban forest (Parque Zoobotânico) and one relatively more preserved area (Seringal Cahoeira) in Rio Branco and Xapuri municipalities. Trypanosoma sp. infection was detected by hemoculture and fresh blood examination. Isolated parasite species were identified by the similarity of the obtained DNA sequence from 18S rDNA polymerase chain reaction and reference strains. Overall, 367 bats from 23 genera and 32 species were examined. Chiropterofauna composition was specific to each municipality, although Artibeus sp. and Carollia sp. prevailed throughout. Trypanosoma sp. infection was detected in 85 bats (23·2%). The most widely distributed and prevalent genotypes were (in order) Trypanosoma cruzi TcI, T. cruzi marinkellei, Trypanosoma dionisii, T. cruzi TcIV and Trypanosoma rangeli. At least one still-undescribed Trypanosoma species was also detected in this study. The detection of T. cruzi TcI and TcIV (the ones associated with Chagas disease in Amazon biome) demonstrates the putative importance of these mammal hosts in the epidemiology of the disease in the Acre State.