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This study evaluates the dynamic shift in the microbiota at the peri-implant site of titanium (Ti) and zirconia (Zr) implants subjected to experimental peri-implantitis (PI) and, for the first time, of implants made of ceria-stabilized alumina-reinforced zirconia (Ce-TZP/Al), a revolutionary zirconia that is set to play a key role in modern implant dentistry. One- and two-piece (TP) implants, including Ce-TZP/AL TP/G3 glass, were placed bilaterally (six implants/side) in five beagle dogs to mimic a natural vs. ligature-induced PI following a split-mouth design. The experiment spanned 30 weeks from tooth extraction. Both PI models promoted plaque deposition at peri-implant sites. Comparatively, the PI induced by ligatures favored the deposition of anaerobes (p = 0.047 vs. natural). Regardless of the model, the plaque deposition pattern was entirely dependent on the implanted material. Ligated Ti and Zr implant sites accumulated up to 2.14 log CFU/mL unit anaerobic load (p ≤ 0.033 vs. non-ligated implant sites), predominantly comprising obligate anaerobes. Naturally occurring PI induced the deposition of co-occurring networks of obligate anaerobes and less oxygen-dependent bacteria. PI induction favored the enrichment of Ti and Zr sites with bacterial taxa belonging to the orange and red complexes (up to 28% increase naturally and up to 71% in the ligated hemiarch). Anaerobic deposition was significantly lower in ligated Ce-TZP/Al implant sites (p ≤ 0.014 vs. TI and Zr) and independent of the induction model (0.63–1 log units of increase). Facultative bacteria prevailed at Ce-TZP/AL sites. The abundance was lower in the Ce-TZP/AL TP implant. Unlike Ti and Zr sites, taxa from the orange and red complexes were negligible. Biofilms configured at the Ti and Zr sites after ligation-induced PI resemble those found in severe IP. We hypothesize that, although surface properties (surface energy and surface roughness) and physicochemical properties of the substrate play an important role in bacterial adhesion and subsequent plaque formation, Ce-TZP/Al modulates several biological activities that preserve the integrity of the gingival seal by limiting PI progression. In conclusion, biofilm progression differs in peri-implant sites according to the specific properties of the material. Ce-TZP/A, unlike titanium or zirconia, prevents dysbiosis in sites subjected to experimental PI and preserves the microbial signature of emergent obligate anaerobes related to PI development.

RESUMO: Um dos fatores de maior preocupação dos pais de filhos com autismo é o déficit na comunicação social. O ensino dos pais de como desenvolver tal habilidade em seu filho, além de ser uma forma de ampliar o tempo de intervenção é um tratamento com resultados satisfatórios. Destaca-se a importância do ensino do ecoico no desenvolvimento da fala da criança por ser um prérequisito para a instalação de comportamentos mais complexos. No que se refere ao cenário pandêmico de isolamento social, faz-se necessária uma intervenção comportamental a distância, e o pacote de Behavior Skills Training (BST) tem sido útil para ensinar pais a aplicarem procedimentos comportamentais em seus filhos. O presente estudo teve como objetivo verificar os efeitos do pacote de treinamento ministrado de modo remoto aos pais sobre o ensino da aplicação do protocolo teste do repertório de ecoico a crianças com autismo. Por meio de um delineamento de linha de base múltipla, foram observados os resultados de três mães participantes, das quais uma apresentou 24% de acertos em linha de base, atingindo 100% após a introdução do BST, o que indicou a eficácia do procedimento de ensino. Após o aprendizado, as mães não voltaram a aplicar o procedimento nos filhos.

The form of a verbal response allows for reinforcement mediation and language transmission across cultures. Reinforcement, in turn, plays a decisive role in learning verbal forms. The present work addresses methodological limitations of previous studies, providing further evidence of the role of automatic reinforcement in achieving parity with vocal models. In the first experiment, 4 preschool-age children heard the experimenter describe drawings of different actions in the passive voice. Participants were then asked to describe analogous drawings. They used the passive voice after the model was presented and continued to do so even when preferred explicit consequences followed diverging descriptions (i.e., in the active voice). To further investigate the effects of explicit reinforcement and of the passive-voice model, in Experiment 2, we altered the number of trials with explicit reinforcement and with the model. Three of four participants used the passive voice to describe the drawings, despite greater exposure to explicit consequences following descriptions diverging from the model.

Matching-to-sample (MTS) training consists of presenting a stimulus as a sample followed by stimuli called comparisons from which a subject makes a choice. This study presents results of a pilot investigation comparing two packages for teaching university students to conduct MTS training. Two groups--control and experimental--with 2 participants in each group were used. Accuracy in conducting MTS training was assessed during baseline and post-training. During training the control group received a manual, and the experimental group received both the manual and computer-aided personalized system of instruction or CAPSI. Baseline and post-training combined scores for control and experimental groups were 72.5% and 100%, and 72.7% and 95%, respectively. Results showed that the manual and the manual-plus-CAPSI packages produced similar effects in delivering knowledge in MTS training. We suggest that future studies using a larger sample size are necessary. In addition, we suggest that it is necessary to test new versions of the manual and the interaction of CAPSI with other components, such as demonstration videos.

Modulating natural killer cell functions in human immunity and reproduction are diverse interactions between the killer cell immunoglobulin-like receptors (KIR) of Natural Killer (NK) cells and HLA class I ligands on the surface of tissue cells. Dominant interactions are between KIR2DL1 and the C2 epitope of HLA-C and between KIR2DL2/3 and the C1 epitope of HLA-C. KhoeSan hunter-gatherers of Southern Africa represent the earliest population divergence known and are the most genetically diverse indigenous people, qualities reflected in their KIR and HLA genes. Of the ten KhoeSan KIR2DL1 alleles, KIR2DL1*022 and KIR2DL1*026 likely originated in the KhoeSan, and later were transmitted at low frequency to the neighboring Zulus through gene flow. These alleles arose by point mutation from other KhoeSan KIR2DL1 alleles that are more widespread globally. Mutation of KIR2DL1*001 gave rise to KIR2DL1*022, causing loss of C2 recognition and gain of C1 recognition. This makes KIR2DL1*022 a more avid and specific C1 receptor than any KIR2DL2/3 allotype. Mutation of KIR2DL1*012 gave rise to KIR2DL1*026, causing premature termination of translation at the end of the transmembrane domain. This makes KIR2DL1*026 a membrane-associated receptor that lacks both a cytoplasmic tail and signaling function. At higher frequencies than their parental allotypes, the combined effect of the KhoeSan-specific KIR2DL1*022 and KIR2DL1*026 is to reduce the frequency of strong inhibitory C2 receptors and increase the frequency of strong inhibitory C1 receptors. Because interaction of KIR2DL1 with C2 is associated with risk of pregnancy disorder, these functional changes are potentially advantageous. Whereas all other KhoeSan KIR2DL1 alleles are present on a wide diversity of centromeric KIR haplotypes, KIR2DL1*026 is present on a single KIR haplotype and KIR2DL1*022 is present on two very similar haplotypes. The high linkage disequilibrium across their haplotypes is consistent with a recent emergence for these KIR2DL1 alleles that have distinctive functions.

Mast cells play key roles in allergy, anaphylaxis/anaphylactoid reactions, and defense against pathogens/toxins. These cells contain cytoplasmic granules with a wide spectrum of pleotropic mediators that are released upon activation. While mast cell degranulation (MCD) occurs upon clustering of the IgE receptor bound to IgE and antigen, MCD is also triggered through non-IgE-mediated mechanisms, one of which is via Mas-related G protein-coupled receptor X2 (MRGPRX2). MRGPRX2 can be activated by many basic biogenic amines and peptides. Consequently, MRGPRX2-mediated MCD is an important potential safety liability for peptide therapeutics. To facilitate peptide screening for this liability in early preclinical drug development, a rapid, high-throughput engineered CHO-K1 cell-based MRGPRX2 activation assay was evaluated and compared to histamine release in CD34+ stem cell-derived mature human mast cells as a reference assay, using 30 positive control and 29 negative control peptides for MCD. Both G protein-dependent (Ca2+ endpoint) and -independent (β-arrestin endpoint) pathways were assessed in the MRGPRX2 activation assay. The MRGPRX2 activation assay had a sensitivity of 100% for both Ca2+ and β-arrestin endpoints and a specificity of 93% (β-arrestin endpoint) and 83% (Ca2+ endpoint) compared to histamine release in CD34+ stem cell-derived mature human mast cells. These findings suggest that assessing MRGPRX2 activation in an engineered cell model can provide value as a rapid, high-throughput, economical mechanism-based screening tool for early MCD hazard identification during preclinical safety evaluation of peptide-based therapeutics.

This study evaluates the dynamic shift in the microbiota at the peri-implant site of titanium (Ti) and zirconia (Zr) implants subjected to experimental peri-implantitis (PI) and, for the first time, of implants made of ceria-stabilized alumina-reinforced zirconia (Ce-TZP/Al), a revolutionary zirconia that is set to play a key role in modern implant dentistry. One- and two-piece (TP) implants, including Ce-TZP/AL TP/G3 glass, were placed bilaterally (six implants/side) in five beagle dogs to mimic a natural vs. ligature-induced PI following a split-mouth design. The experiment spanned 30 weeks from tooth extraction. Both PI models promoted plaque deposition at peri-implant sites. Comparatively, the PI induced by ligatures favored the deposition of anaerobes (p = 0.047 vs. natural). Regardless of the model, the plaque deposition pattern was entirely dependent on the implanted material. Ligated Ti and Zr implant sites accumulated up to 2.14 log CFU/mL unit anaerobic load (p ≤ 0.033 vs. non-ligated implant sites), predominantly comprising obligate anaerobes. Naturally occurring PI induced the deposition of co-occurring networks of obligate anaerobes and less oxygen-dependent bacteria. PI induction favored the enrichment of Ti and Zr sites with bacterial taxa belonging to the orange and red complexes (up to 28% increase naturally and up to 71% in the ligated hemiarch). Anaerobic deposition was significantly lower in ligated Ce-TZP/Al implant sites (p ≤ 0.014 vs. TI and Zr) and independent of the induction model (0.63–1 log units of increase). Facultative bacteria prevailed at Ce-TZP/AL sites. The abundance was lower in the Ce-TZP/AL TP implant. Unlike Ti and Zr sites, taxa from the orange and red complexes were negligible. Biofilms configured at the Ti and Zr sites after ligation-induced PI resemble those found in severe IP. We hypothesize that, although surface properties (surface energy and surface roughness) and physicochemical properties of the substrate play an important role in bacterial adhesion and subsequent plaque formation, Ce-TZP/Al modulates several biological activities that preserve the integrity of the gingival seal by limiting PI progression. In conclusion, biofilm progression differs in peri-implant sites according to the specific properties of the material. Ce-TZP/A, unlike titanium or zirconia, prevents dysbiosis in sites subjected to experimental PI and preserves the microbial signature of emergent obligate anaerobes related to PI development. [ABSTRACT FROM AUTHOR]

Há uma crescente representatividade das pessoas com Transtorno do Espectro do Autismo (TEA) por meio das mídias sociais e engajamento de familiares de crianças, jovens e de adultos com TEA nas discussões de políticas públicas que visem o acesso pleno aos direitos. Considerando que a inclusão de adultos com TEA no mercado de trabalho é um direito assegurado por lei e que a inclusão escolar deve auxiliar na preparação para o mercado de trabalho, a fim de oportunizar acesso à cidadania, este artigo objetivou verificar a produção acadêmica acerca da inclusão de adultos autistas no mercado de trabalho, buscando experiências desta inclusão. O procedimento de coleta de dados foi uma revisão de literatura nas bases de dados Scielo, Google Acadêmico e Biblioteca Digital Brasileira de Teses e Dissertações, entre os anos 2010 e 2019. A análise dos dados consistiu na apresentação dos dados quantitativos e na análise qualitativa dos trabalhos encontrados, considerando o objetivo deste estudo. Foram encontrados treze artigos dentro da temática, contudo apenas três relatavam experiências de inclusão no mercado de trabalho de adultos com TEA. É possível constatar que há insuficiência de estudos na área. Todas as publicações evidenciam a necessidade de sensibilização dos empregadores, acesso a informação sobre as especificidades do TEA, conhecimento sobre os direitos da pessoa com TEA no ambiente de trabalho, criação de política de inclusão da instituição empregadora, participação e apoio da família das pessoas com TEA nesse processo de inserção no mercado de trabalho.

In this two-phase study, it was shown that a mixture with equal parts of manure and resulting animal blood was the optimal combination for obtaining biogas and biol. A quadratic growth trend in variable gas pressure over time—as well as its behavior—was confirmed for pHs around the neutral value for the substrate used in both the pilot phase and in the microplant, which had a mechanical implementation and mechatronic system for the control of variables that intervene in the anaerobic digestion process; this allowed for the confirmation of the results found in the first phase of research—without concerns that a lack of control over the process variables would cause—in such a way that it constituted a path for the industrialization of the waste treatment process in slaughterhouses that could be optimized by the use of the optimal combination that produces the greatest cm3 amount of gas. Anaerobic digestion in biodigesters is carried out at different constant temperature values within the mesophilic range, with a hydraulic retention time of 25 days. A direct relationship was found between temperature, biogas production and pH behavior in the buffer(s). The pH remained close to neutral and the gas pressure increased from 15 to 20. The findings indicated that the value for the C/N ratio of the blood of four was compensated for by its buffer system, composed of bicarbonate, hemoglobin, proteins and phosphates.

The identification and treatment of autism spectrum disorder (ASD) has greatly improved the lives of people with the condition, leading to greater access to mainstream education and a higher quality [...], This study extended previous research on the effect of education and communication on anti-autism bias and stigmatization, using the Implicit Relational Assessment Procedure (IRAP) as an assessment tool and employing undergraduates as participants. Experiment 1 examined the effect of a simple video and text-based educational intervention on attitudes towards autism, as assessed both using the IRAP and various explicit measures. Participants received either an educational video-text combination or a control video-text combination before exposure to the assessments. Findings showed positive responding towards both normally developing and autism spectrum individuals across both conditions on both the IRAP and the explicit measures. Experiment 2 investigated the effects of two different types of online video-based narrative regarding autism, one negatively oriented and the other positively oriented, on both implicit and explicit responding. Findings suggested that the negative video affected both implicit and explicit responding, albeit in different ways. Responding on the IRAP showed a stronger pro-normally developing bias whereas explicit responding showed a stronger anti-autism bias. Implications and possible future directions are discussed. Keywords Education * Public messaging * Implicit attitudes * Autism * Implicit Relational Assessment Procedure * Relational frame theory

"The Analysis of Verbal Behavior" ("TAVB") is the only journal focused on theoretical and empirical research in verbal behavior. An assessment of authorship trends can provide a critical perspective on practices in verbal behavior analysis (e.g., participation by non-US institutions, contributions by female authors). The present study examines authorship trends in all articles published in "TAVB" since its inception (between 1982 and 2016). All authors and their affiliations were listed and the first authors denoted as such. Authors were characterized as follows: prolificacy, new vs. frequent contributor status, number of co-authors, editor status, fellow status in a professional organization, and gender. Institutional affiliations were characterized as follows: academic vs. nonacademic institutions, prolificacy, and location (country). The review included 383 articles by 487 authors from 200 institutions. Our findings revealed areas in which "TAVB" is reaching maturity (e.g., author gender) and areas in which further action by contributors and editors is needed (e.g., international participation).

Bryan, Theriault, and Bryan (2015) describe self-forgiveness as an 'act of generosity and kindness toward the self, following self-perceived inappropriate action' (p. 40). Self-forgiveness has been examined across a range [...], A key aspect of self-forgiveness is that one needs to acknowledge one's failings and their consequences. The present study used the Implicit Relational Assessment Procedure (IRAP) and an explicit IRAP analog measure to examine (1) responding to perceived failure following exposure to an insoluble task, and (2) the effect of a defusion intervention on responding in this context. Participants (n = 29) were first assessed for baseline performance on an IRAP and IRAP analog that assessed participants in terms of perceived relations between performance (success vs. failure) and feelings (positive vs. negative). They were then exposed to the insoluble task, after which they were asked to report on their performance and their feelings in relation to the task. They were subsequently assigned to hear either a defusion (n = 14) or control (n = 15) audio recording and were reexposed to the implicit and explicit measures. IRAP results showed significant denial of failure as leading to positive feelings for both groups following the insoluble task, whereas the explicit (IRAP analog) measure failed to show any comparable effect of this task. As regards the defusion intervention, no effect was seen at the implicit level whereas effects at the explicit level were ambiguous. Results and future directions are discussed. Keywords Self-forgiveness * Defusion * Relational frame theory * Implicit Relational Assessment Procedure (IRAP) * Acceptance and commitment therapy

Context: Bauhinia L. species, including Bauhinia holophylla (Bong.) Steud. (Fabaceae), have traditionally been used to treat diabetes. Bauhinia is a complex botanical genus, and the indiscriminate use of the diverse Bauhinia species is reflected in the experimental divergence of their medicinal potential. Objective: The hypoglycaemic and hypolipidaemic effects, molecular mechanism of action and phytochemical properties of an authentic extract of B. holophylla leaves were evaluated. Materials and methods: A phytochemical study of a 70% EtOH extract was performed using FIA-ESI-IT-MS/MSn and HPLC-PAD-ESI-IT-MS. The extract (200 or 400 mg/kg b.w.) was administered for 14 days to streptozotocin-induced diabetic Swiss mice. Glucose tolerance and insulin sensitivity, blood parameters, gene and protein expression, and the in vivo and in vitro inhibition of intestinal glucosidases were assessed. Results: HPLC-PAD-ESI-IT-MS analysis identified flavonoid derivatives of quercetin, myricetin, luteolin and kaempferol. Treatment with 400 mg/kg of the extract reduced blood glucose (269.0 ± 32.4 mg/dL vs. 468.0 ± 32.2 mg/dL for diabetic animals), improved glucose tolerance, decreased cholesterol and triglyceride levels, and increased the mRNA expression of proteins involved in glucogenesis in the liver and muscle, such as PI3-K/Akt, GS, GSK3-β (ser-9), AMPK and Glut4. The activity of intestinal maltase was inhibited in vitro (IC50: 43.0 µg/mL for the extract compared to 516.4 µg/mL for acarbose) and in vivo. Discussion and conclusions: Treatment with B. holophylla was associated with a marked hypoglycaemic effect through the stimulation of glycogenesis and inhibition of gluconeogenesis and intestinal glucose absorption, without increasing basal insulinaemia.

In the Andeans, it is common to find homemade containers, chairs, structures made with Schoenoplectus californicus sub. californicus, commonly known as totora. Popularly is known that the homemade products possess resistance and durability due to the incorporation of this fiber, although nowadays the mechanic properties of this material are unknown. This research begins with the study of the variety of the totora which is present in the Province of Imbabura, Ecuador. Considering the geometrical variation of the stem, it is divided in three parts. Based on standard ASTM D4761-02a totora is characterized under tension. Finally, the mechanic characteristics under tension of Schoenoplectus californicus are presented from the stress-strain curve and its comparative analysis among the groups of transversal sections. It is determined that its behavior corresponds to a fragile material with an average of maximum stress up to 88.501 6.92 MPa, and an average of a maximum strain of 0.05132 0.00610 mm/mm.

Discrete-trial instruction (DTI) is a behavioral method of teaching young children with autism spectrum disorders (ASD) that has received a significant amount of research support. Because of a lack of qualified trainers in many areas of the world, researchers have recently begun to investigate alternative methods of training professionals to implement behavioral teaching procedures. One promising training method is interactive computer training, in which slides with recorded narration, video modeling, and embedded evaluation of content knowledge are used to teach a skill. In the present study, the effectiveness of interactive computer training developed by Pollard, Higbee, Akers, and Brodhead (2014), translated into Brazilian Portuguese, was evaluated with 4 university students (Study 1) and 4 special education teachers (Study 2). We evaluated the effectiveness of training on DTI skills during role-plays with research assistants (Study 1) and during DTI sessions with young children with ASD (Studies 1 and 2) using a multiple baseline design. All participants acquired DTI skills after interactive computer training, although 5 of 8 participants required some form of feedback to reach proficiency. Responding generalized to untaught teaching programs for all participants. We evaluated maintenance with the teachers in Study 2, and DTI skills were maintained with 3 of 4 participants.

Recently, there has been a proliferation of research on the functional independence of two of Skinner's (1957) verbal operants, the mand, and the tact. This research has produced highly variable results. In this article, we provide a critical review of the literature on mand-tact independence, a literature that has implications for both theory and practice. Included in the review are 17 studies with a total of 66 participants who were tested for mand emergence following tact training, tact emergence following mand training, or both, and 11 additional studies that systematically manipulated variables expected to affect the outcomes of such tests. A primary finding is that most studies to date suffer from problems with construct validity. However, it may be justifiable to conclude that the literature provides at least weak support for the functional independence of mands and tacts. Future investigators should avoid the major construct validity pitfalls described in this article, describe participant characteristics more thoroughly, and consider alternative approaches to studying mand-tact independence.

En el presente trabajo se evaluó la capacidad aislante de paneles elaborados a base de la Typha Latifolia en diferentes formas. Los resultados muestran una capacidad aislante relevante, catalogando la totora como un elemento de potencial aplicación como aislamiento en edificaciones. El desarrollo de aislantes térmicos basados en residuos de biomasa es una línea de investigación prometedora que permitirá la mejora sustancial de la eficiencia energética, así como el confort térmico del hábitat con soluciones sustentables de bajo coste. El desarrollo de elementos constructivos contemporáneos como paneles o mantas de totora, permitirá la mejora de la sustentabilidad de soluciones industriales, así como la reducción importante del coste de producción de estas. In this paper the insulating capacity of panels made of Typha latifolia in different forms was evaluated. The results show a significant insulating capacity, placing the cattail as a potential isolating element in buildings. The development of thermal insulation elements based on biomass residues is a promising line of research that will provide substantial improvement in energy efficiency and thermal comfort with sustainable habitat solutions at low cost. The development of contemporary construction elements such as panels or blankets of totora, will permit the improvement of industrial solutions sustainability and a significant reduction in the cost of its production.

En esta investigación se realiza un análisis de las prestaciones y emisiones de un motor Petter mono-cilíndrico de inyección directa al usar como combustible una emulsión de 5% de agua, 2%de surfactante y combustible diesel. Los resultados obtenidos con la emulsión muestran un ligero incremento en el torque y la potencia efectiva, así como en el consumo específico de combustible y el retardo de la ignición. Respecto a las emisiones de gases contaminantes, los hidrocarburos noquemados (HC) y el monóxido de carbono (CO) para la emulsión aumentaron en comparación con los resultados obtenidos para el combustible diesel. En ambos casos, los aumentos son unaconsecuencia de la disminución de las temperaturas en el interior de la cámara de combustión, los aumentos en el retardo de la ignición y al enfriamiento de la llama. In this investigation an analysis based on the performances and emission of a Petter single cylinder direct injection diesel engine when using an emulsion of 5% of water, 2% of surfactant and dieselfuel as fuel is carried out. The result obtained with the emulsion tested shown slight increase in effective torque and power output, but also increases in brake specific fuel consumption and ignition delay. Concerning the exhausts, increases in hydrocarbons (HC) and carbon monoxide(CO) emissions for emulsion were obtained. In both cases the increases are due to the effect of lower temperatures inside the combustion chamber, longer ignition delays and quenching of the flame.

This study investigated the effect of matching-to-sample and mimetic-relations teaching on the emergence of signed tact and textual repertoire through a multiple-baseline design, across three groups of three words in children with and without hearing impairments and with no reading repertoire. Following mimetic-relations teaching and the establishment of nine three-member stimulus classes containing signs, pictures, and printed words via matching-to-sample procedure, including the mimetic relation as the differential observing response, tact (signing in the presence of a picture) and textual (signing in the presence of a printed word) emergent repertoires were tested. Results showed the emergence of signed tact and textual responses. The mimetic relation brought in under the contextual control of a matching-to-sample task may have allowed participants to simultaneously learn speaker and listener relations to the particular signs used. (Contains 4 tables and 1 figure.)

The purpose of the current study was to assess whether individuals with intellectual disabilities would emit untrained speaker responses (i.e., signed tacts and mands) after being taught listener behaviors. Listener relations were trained via an automated matching-to-sample (MTS) procedure. Following mastery, the emergence of signed tacts, generalized tacts, and mands was tested. All participants met criterion in listener relations training and showed the emergence of almost all relations. Results suggest that teaching listener relations first, through MTS tasks, is a viable way to produce emergence of speaker relations. (Contains 2 tables and 1 figure.)

The objective of this study was to teach manual signs through an automated matching-to-sample procedure and to test for the emergence of new conditional relations and imitative behaviors. Seven adults with mild to severe mental retardation participated. Four were also hearing impaired. Relations between manual signs (set A) and pictures (set B) were initially taught, followed by the training of corresponding printed words (set C) and pictures (set B). Further presentations of conditional discriminations tested for the emergence of AC, followed by tests for the emergence of imitative signing behavior (D) in the presence of either pictures (B) or printed words (C). Each stimulus set was comprised of 9 elements. The stimuli were still pictures, printed words, and dynamic presentations of manual signs. A pretest was conducted to determine which signs the participants could make pre-experimentally. Teaching was arranged in a multiple baseline design across 3 groups of 3 words each.The purpose of the present study was to determine whether participants would emit manual signs in expressive signs tests as a result of observation (video modeling) during match-to-sample training in the absence of explicit training. Five of the 7 subjects passed tests of emergence and emitted at least 50% of the signs. Two were hearing impaired with signing experience, and 3 were not hearing impaired and had no signing experience. Thus, observation of video recorded manual signs in a matching-to-sample training procedure was effective at establishing some signs by adults with mental retardation. (Contains 4 tables and 5 figures.)

A aprendizagem das relações verbais de tato podem apresentar características de emergência e manutenção diferentes das relações textuais. Essas diferenças despertam particular interesse quando os estímulos que controlam tais operantes verbais pertencem à mesma classe de equivalência e a topografia da resposta é semelhante. O objetivo deste trabalho foi investigar o papel da função reforçadora de cada uma dessas relações na emergência de novas relações. Inicialmente, seis universitários participaram do estudo. Primeiro, foram ensinadas, através de tarefas de matching-to-sample, relações de ouvinte entre palavras ditadas e figuras, e entre palavras ditadas e palavras impressas. Após ensino, foram testadas as relações de equivalência, e a emergência de relações de tato e textual - consideradas relações de falante. Em seguida, os participantes foram submetidos a esquemas concorrentes com encadeamento para verificar a preferência por tarefas. Os resultados indicaram indiferença na preferência por tarefas, o que é consistente com o estabelecimento das relações de equivalência e com o fato dos participantes demonstrarem desempenho similar nos testes de tato e leitura. A ausência de preferência pode ter sido observada em função da indiferença da função reforçadora desses operantes, mas também pelo fato dos participantes terem um vasto e sofisticado repertório verbal.

El presente trabajo tiene como objetivo caracterizar el desempeño de un motor diesel en cuanto a sus prestaciones y al retardo de la ignición, al operar bajo diferentes regímenes de carga, empleando mezclas de aceite de Jatropha y combustible diesel. Para esto se determinó la característica exterior de velocidad al emplear las mezclas, y se compararon estos resultados con los obtenidos durante los ensayos con combustible diesel patrón; estableciendo el grado de afectación del motor al sustituir parte del combustible diesel por aceite de Jatropha. Se observó una disminución del torque y la potencia efectiva, y un aumento del consumo específico de combustible al emplear un mayor porciento de aceite de Jatropha en las mezclas. Por otra parte, en comparación con el combustible diesel, el retardo de la ignición no mostró una variación significativa al emplear las mezclas de aceite de Jatropha y combustible diesel.The present study aims to characterize the benefits of a diesel engine in terms of performance and ignition delay, operating under different loading regimes, using Jatropha oil and diesel fuel blends. We determined the speed exterior feature when using mixtures, and compared these results with those obtained during tests with standard diesel fuel, establishing the degree of involvement of the engine to replace some diesel fuel for Jatropha oil. There was a decrease in the torque and effective power, and increased specific fuel consumption by using a higher percentage of Jatropha oil in blends. Moreover, compared to diesel fuel, the ignition delay showed no significant variation by employing Jatropha oil and diesel fuel blends.

Se estudia la influencia del silicio y el tratamiento térmico sobre la microestructura y la resistencia al desgaste abrasivo y por fricción seca de una fundición con 3 % C y 12 % Cr, obtenida en condiciones de rápida solidificación. La rápida solidificación disminuye el volumen de carburos, la finura y dispersión de éstos aumentan con el incremento del silicio. Todas las muestras presentaron matrices perlíticas, variando en finura con el tratamiento. No se apreciaron productos de transformación intermedios. Las durezas tuvieron poca variación. Los tratamientos de austenización mostraron poca efectividad, con tendencia a desgastes más elevados que en estado bruto de colada y con tratamiento de mantenimiento. Los comportamientos ante la abrasión y la fricción seca en las condiciones ensayadas fueron similares. Se evidenció alta influencia de la morfología de los carburos en el desgaste abrasivo.

El número de cetano (CN) es una de las propiedades más importantes para evaluar la calidad del proceso de combustión de un combustible tipo diesel. El CN de biocombustibles derivados de aceites vegetales está influenciado por su composición de ácidos grasos. El objetivo de esta investigación es obtener dos modelos físico-matemáticos que establezcan una relación entre el número de cetano de biocombustibles derivados de aceites vegetales y su composición de ácidos grasos esenciales. Para predecir el CN se desarrollaron dos modelos mediante un análisis de regresión múltiple, basado en datos experimentales extraídos de bases de datos referenciadas. El ajuste de los coeficientes del modelo se basa en la obtención de residuales mínimos. Se realiza una validación parcial del modelo y se establecen las pautas para la validación total del mismo. A partir de estos resultados queda establecida una herramienta muy útil para la determinación del número de cetano. Palabras claves: número de cetano, biodiesel, aceites vegetales, ácidos grasos.______________________________________________________________________________ Abstract The cetane number is one of the main properties for characterization of the ignition quality of a fuel for its use in a diesel engine. The cetane number of biofuels obtained from different vegetable oils is strongly considerably by their fatty acid composition. The scope of this research is to obtain two physical-mathematical models that establish a relationship between the cetane number and the composition of different biofuels derived from vegetable oils. The models were developed using an analysis of multiple regression, based on experimental data available in the literature. The coefficients adjustment of the model was based on the obtaining of lower residual in the capacity of prediction of the model. A partial validation of the model was developed. Starting from these results it a very useful tool for the determination of such an important parameter was established. Key words: cetane number, biodiesel, vegetable oils, fatty acid.

Miconia is one of the largest genus of the Melastomataceae, with approximately 1,000 species. Studies aiming to describe the diverse biological activities of the Miconia species have shown promising results, such as analgesic, antimicrobial and trypanocidal properties. M. albicans leaves were dried, powdered and extracted to afford chloroformic and methanolic extracts. Total phenolic contents in the methanolic extract were determined according to modified Folin-Ciocalteu method. The antioxidant activity was measured using AAPH and DPPH radical assays. Chemical analysis was performed with the n-butanol fraction of the methanolic extract and the chloroformic extract, using different chromatographic techniques (CC, HPLC). The structural elucidation of compounds was performed using 500 MHz NMR and HPLC methods. The methanolic extract showed a high level of total phenolic contents; the results with antioxidant assays showed that the methanolic extract, the n-butanolic fraction and the isolated flavonoids from M. albicans had a significant scavenging capacity against AAPH and DPPH. Quercetin, quercetin-3-O-glucoside, rutin, 3-(E)-p-coumaroyl-α-amyrin was isolated from the n-butanolic fraction and α-amyrin, epi-betulinic acid, ursolic acid, epi-ursolic acid from the chloroformic extract. The results presented in this study demonstrate that M. albicans is a promising species in the search for biologically active compounds.