1,568 research outputs found
From semantic underdetermination via metaphor and metonymy to conceptual interaction
The question of semantic underdetermination is related to the distinction between what is said and what is implicated. In this paper we examine the relevance-theoretic notion of enrichment as a procedure for developing what is said into a fully specified proposition or explicature. We make the claim that there are two forms of such a procedure, viz. grammatically-motivated and conceptually-motivated enrichment, and discuss their role in communication. We further contend that the notion of enrichment and the other procedures of propositional development recognized in the relevance-theoretic literature are insufficient to account for all cases of explicated meaning. In this connection, we propose other cognitive mechanisms such as mitigation and more interestingly-metaphoric and metonymic mappings. This discussion allows us to cast some light on the implicature/explicature division line and to rank as explicatures some cases of inferences which have so far been considered as implicatures, including those where metaphor and metonymy are involved. Finally we examine the role of metaphoric and metonymic mappings - both in isolation and as part of conceptual interaction systems - in the production of explicatures, which allows us to understand better the communicative potential of these cognitive mechanisms
Egg-recognition abilities in non-incubating males:Implications for the evolution of anti-parasitic host defenses
In the field of brood parasitism, it has been traditionally assumed that only the incubating sex rejects parasitic eggs, but this assumption has been rarely explored despite its important implications for the evolutionary relationship between brood parasites and hosts. Here, we used information on previous egg-rejection experiments to explore the recognition abilities of both males and females of Eurasian blackbirds Turdus merula towards experimental eggs with a variable degree of mimicry. We found that both sexes recognized non-mimetic eggs, supporting the idea that visits to the nest can favor the evolution of rejection abilities. In contrast, only females recognized mimetic eggs, indicating that although recognition abilities can evolve in both sexes, they are subsequently refined in females probably due to their more frequent interaction with parasitic eggs. Clutch size affected nest attendance since females, but not males, spent more time at the nest and visited it more frequently in larger clutches. Finally, our recordings showed that blackbird males are able not only to recognize, but also to eject parasitic eggs. Our results provide new insights into the main anti-parasitic defense in birds, egg rejection, and highlight the need of considering the role of the non-incubating sex in egg-rejection studies.Significance statementGiven the high costs associated to avian brood parasitism, both sexes are expected to evolve anti-parasitic defenses. However, in those species in which only females incubate, females have traditionally been assumed to be the responsible for egg rejection. Here, using the Eurasian blackbird (Turdus merula), we investigated the existence of egg-rejection abilities in non-incubating males and compared them to those exhibited by females. We found that males can recognize non-mimetic eggs, although their recognition abilities were less fine-tuned compared to females, who also recognized mimetic eggs. Even though females were the responsible for most documented egg-ejection events, recordings confirmed that males could also be involved in egg ejection, which could have important implication for the evolution of anti-parasitic defenses in host populations
Fecal sacs attract insects to the nest and provoke an activation of the immune system of nestlings
Background: Nest sanitation is a widespread but rarely studied behavior in birds. The most common form of nest
sanitation behavior, the removal of nestling feces, has focused the discussion about which selective pressures
determine this behavior. The parasitism hypothesis, which states that nestling fecal sacs attract parasites that
negatively affect breeding birds, was proposed 40 years ago and is frequently cited as a demonstrated fact. But,
to our knowledge, there is no previous experimental test of this hypothesis.
Results: We carried out three different experiments to investigate the parasitism hypothesis. First, we used
commercial McPhail traps to test for the potential attraction effect of nestling feces alone on flying insects. We
found that traps with fecal sacs attracted significantly more flies (Order Diptera), but not ectoparasites, than the
two control situations. Second, we used artificial blackbird (Turdus merula) nests to investigate the combined
attraction effect of feces and nest materials on arthropods (not only flying insects). Flies, again, were the only
group of arthropods significantly attracted by fecal sacs. We did not detect an effect on ectoparasites. Third, we
used active blackbird nests to investigate the potential effect of nestling feces in ecto- and endoparasite loads
in real nestlings. The presence of fecal sacs near blackbird nestlings did not increase the number of louse flies or
chewing lice, and unexpectedly reduced the number of nests infested with mites. The endoparasite prevalence was
also not affected. In contrast, feces provoked an activation of the immune system as the H/L ratio of nestlings living
near excrements was significantly higher than those kept under the two control treatments.
Conclusions: Surprisingly, our findings do not support the parasitism hypothesis, which suggests that parasites are not
the main reason for fecal sac removal. In contrast, the attraction of flies to nestling feces, the elevation of the immune
response of chicks, and the recently described antimicrobial function of the mucous covering of fecal sacs suggest that
microorganisms could be responsible of this important form of parental care behavior (microbial hypothesisPeer reviewe
Integration of Membrane Distillation with solar photo-Fenton for purification of water contaminated with Bacillus sp. and Clostridium sp. spores
CO2 capture and conversion: A homemade experimental approach
During the SARS-2-Covid pandemic our institution sought to continue the teaching and learning of experimental laboratories by designing, assembling, and delivering a microscale chemistry kit to the students’ homes. Thanks to this approach students were able to perform ~25 experiments during each one of the Fall 2020 and Spring 2021 semesters in an elective Electrochemistry and Corrosion course offered to Chemical Engineering undergraduates. In addition to performing traditional experiments, students were encouraged to design some of their own and have the entire group reproduce them. One of such student-designed experiments involved the capture of CO2 and its reduction with a readily available active metal (i.e., Al foil) in aqueous media to generate potentially useful products. The highly negative standard potential of Al is exploited for the reduction of lab-generated CO2, and the products are chemically tested. Al as a foil has been reported to be electrochemically inactive for carbon dioxide reduction. However, encouraged by an earlier report of the reduction of CO2 to CO, the Al surface is activated in the present experiment by removal of its natural oxide layer with a solution of CuCl 2 produced in an electrochemical cell. This procedure enables Al to react with CO2 and yield useful chemistry. This experiment turned to be a discovery trip. The detailed procedure is discussed here, as well as the teaching methodology, grading scheme, and student outcomesPeer Reviewe
PRODUTIVIDADE E CARACTERÍSTICAS REPRODUTIVAS DO ARUANÃ, Osteoglossum bicirrhosum (OSTEOGLOSSIFORMES: OSTEOGLOSSIDAE), NO LAGO GRANDE, BACIA DO RIO PUTUMAYO, PERU
Due to the importance of ornamental fishing of silver arowana, as well as, Lago Grande lake as one of the main areas for capturing baby arowanas in Peru, the present study aimed to evaluate the productivity and the biological-reproductive characteristics of the species in the lake, which is located in the lower basin of the Putumayo River and represents an area preferred by fishermen because the important populations of silver arowana inhabiting it. Analysis of population density, biometrics, sexual maturity, spawning, fecundity, sex ratio, water level of the lake and production of baby arowana were made. The study was developed between March and July of 2012 and to implement the activities of the study was important the participation of the Association of Fishermen “Fronteras Vivas”. In general, the population density extrapolated to the lake area was 1.29 fish/ha. Of these, the density of progenitors in the lake was 1.19 fish/ha. Also, male animals had total length, standard length and total weight higher than females and it was observed that the spawning period occurred in synchronization with the start of the growing of the hydrological regime. The average number of oocytes produced by females of silver arowana in the study area was 201 and the sex ratio was equilibrated. Furthermore, the study shows the capacity of production of the lake. In order to this the water lever influenced in the production of baby arowanas. It is important to continue studying the species for regulate the fishing and recover populations.Keywords: baby arowana; production; ornamental trade; length of first sexual maturity; fishing.Devido à importância da pesca ornamental de aruanã, e da lagoa Lago Grande como uma das principais áreas para a captura de alevinos de aruanã no Peru, o presente estudo tive como objetivo avaliar a produtividade e as características reprodutivas na espécie na lagoa, a mesma que está localizada na bacia baixa do Rio Putumayo e representa uma das áreas de pesca preferidas pela importante população de aruanã que a habitam. Foram feitas análises de densidade populacional, biometria, maturidade sexual, desova, fecundidade, proporção sexual, níveis da água na lagoa e sobre a produção de alevinos de aruanã. O estudo foi desenvolvido entre março a julho de 2012 e as atividades foram realizadas em parceria com a Agrupação de Pescadores “Fronteras Vivas”. De modo geral, a densidade populacional extrapolada à área da lagoa foi de 1.29 peixes∕ha. Daqueles, a densidade de progenitores na lagoa foi de 1.19 peixes∕ha. Além disso, os machos tiveram comprimento total e padrão e peso total maior do que as fêmeas, e foi observado que o período de desova ocorreu em sincronia com o início da crescente no nível das águas. A média de oocitos produzidos por fêmeas de aruanã foi de 201 e a proporção sexual foi equilibrada. Assim mesmo, o estudo mostra a capacidade de produção da lago. Nesse sentido, o nível da água influenciou na produção de alevinos de aruanã. É importante continuar os estudos da espécie para regulamentar a pesca e recuperar populações.Palavras-chave: alevinos de aruanã, produção, comércio ornamental, comprimento de primeira maturidade sexual, pesca
Photon, Neutrino and Charged Particle Spectra from R-violating Gravitino Decays
We study photonic, neutrino and charged particle signatures from slow decays
of gravitino dark matter in supersymmetric theories where R-parity is
explicitly broken by trilinear operators. Photons and (anti-)fermions from loop
and tree-level processes give rise to spectra with distinct features, which, if
observed, can give crucial input on the possible mass of the gravitino and the
magnitude and flavour structure of R-violating operators. Within this
framework, we make detailed comparisons of the theoretical predictions to the
recent experimental data from PAMELA, ATIC and Fermi LAT.Comment: Version published in Phys. Lett.
Accurate quantification of atherosclerotic plaque volume by 3D vascular ultrasound using the volumetric linear array method.
Direct quantification of atherosclerotic plaque volume by three-dimensional vascular ultrasound (3DVUS) is more reproducible than 2DUS-based three-dimensional (2D/3D) techniques that generate pseudo-3D volumes from summed 2D plaque areas; however, its accuracy has not been reported. We aimed to determine 3DVUS accuracy for plaque volume measurement with special emphasis on small plaques (a hallmark of early atherosclerosis).
The in vitro study consisted of nine phantoms of different volumes (small and medium-large) embedded at variable distances from the surface (superficial vs. >5 cm-depth) and comparison of 3DVUS data generated using a novel volumetric-linear array method with the real phantom volumes. The in vivo study was undertaken in a rabbit model of atherosclerosis in which 3DVUS and 2D/3D volume measurements were correlated against gold-standard histological measurements.
In the in vitro setting, there was a strong correlation between 3DVUS measures and real phantom volume both for small (3.0-64.5 mm(3) size) and medium-large (91.1-965.5 mm(3) size) phantoms embedded superficially, with intraclass correlation coefficients (ICC) of 0.99 and 0.98, respectively; conversely, when phantoms were placed at >5 cm, the correlation was only moderate (ICC = 0.67). In the in vivo setting there was strong correlation between 3DVUS-measured plaque volumes and the histological gold-standard (ICC = 0.99 [4.02-92.5 mm(3) size]). Conversely, the correlation between 2D/3D values and the histological gold standard (sum of plaque areas) was weaker (ICC = 0.87 [49-520 mm(2) size]), with large dispersion of the differences between measurements in Bland-Altman plots (mean error, 79.2 mm(2)).
3DVUS using the volumetric-linear array method accurately measures plaque volumes, including those of small plaques. Measurements are more accurate for superficial arterial territories than for deep territories.S
Does Socioeconomic Status Influence the Risk of Subclinical Atherosclerosis?: A Mediation Model
BACKGROUND: Socioeconomic status (SES)-education, income level, and occupation-is associated with cardiovascular risk. OBJECTIVES: This study aimed to investigate the association between SES and subclinical atherosclerosis and the potential mechanisms involved. METHODS: SES, lifestyle habits (smoking, dietary patterns, physical activity, and hours of sleep), traditional risk factors, and subclinical atherosclerosis extent were prospectively assessed in 4,025 individuals aged 40 to 54 years without known cardiovascular disease enrolled in the PESA (Progression of Early Subclinical Atherosclerosis) study. After factors associated with atherosclerosis were identified, a multiple mediation model was created to quantify the effect of SES on subclinical atherosclerosis as explained by lifestyle behaviors. RESULTS: Although education level was significantly associated with the presence of atherosclerosis, no differences were found according to income level in this population. Participants with lower education presented with a higher risk of generalized atherosclerosis than those with higher education (odds ratio: 1.46; 95% confidence interval: 1.15 to 1.85; p = 0.002). Lifestyle behaviors associated with both education level and atherosclerosis extent were: smoking status, number of cigarettes/day, and dietary pattern, which explained 70.5% of the effect of SES on atherosclerosis. Of these, tobacco habit (smoking status 35% and number of cigarettes/day 32%) accounted for most of the explained differences between groups, whereas dietary pattern did not remain a significant mediator in the multiple mediation model. CONCLUSIONS: Despite the relative economic homogeneity of the cohort, lower education level is associated with increased subclinical atherosclerosis, mainly mediated by the higher and more frequent tobacco consumption. Smoking cessation programs are still needed, particularly in populations with lower education level.The PESA study is cofunded equally by the Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; and Banco Santander, Madrid, Spain. The study also receives funding from the Institute of Health Carlos III (PI15/02019) and the European Regional Development Fund. The CNIC is supported by the Ministry of Economy, Industry and Competitiveness and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505). This work is part of a project that has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No707642; and from the American Heart Association under grantnumber14SFRN20490315. Dr. Bueno has received research funding from the Instituto de Salud Carlos III (PIE16/00021), AstraZeneca, Bristol-Myers Squibb, Janssen, and Novartis; has received consulting fees from Abbott, AstraZeneca, Bayer, Bristol-Myers Squibb-Pfizer, and Novartis; and has received speaking fees or support for attending scientific meetings from AstraZeneca, Bayer, Bristol-Myers Squibb-Pfizer, Ferrer, Novartis, Servier, and MEDSCAPE-the heart.org.S
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