Refining predictions of population decline at species’ rear edges Vilà Cabrera, Albert; Premoli Il'grande, Andrea Cecilia; Jump, Alistair According to broad‐scale application of biogeographical theory, widespread retractions of species' rear edges should be seen in response to ongoing climate change. This prediction rests on the assumption that rear edge populations are “marginal” since they occur at the limit of the species' ecological tolerance and are expected to decline in performance as climate warming pushes them to extirpation. However, conflicts between observations and predictions are increasingly accumulating and little progress has been made in explaining this disparity. We argue that a revision of the concept of marginality is necessary, together with explicit testing of population decline, which is increasingly possible as data availability improves. Such action should be based on taking the population perspective across a species' rear edge, encompassing the ecological, geographical and genetic dimensions of marginality. Refining our understanding of rear edge populations is essential to advance our ability to monitor, predict and plan for the impacts of environmental change on species range dynamics.

Afrontando el invierno: La rana de ceja corta se reproduce y desarrolla en condiciones climáticas adversas Jara, Fabian Gaston; Cuello, Maria Elena; Úbeda, Carmen A. Los anfibios anuros del bosque andino-patagónico muestran una amplia variedad de adaptaciones a diferentes ambientes acuáticos y a condiciones ambientales regionales. Dentro de estas adaptaciones se destacan particularidades en el ciclo de vida, como por ejemplo que todo o la mayor parte del ciclo transcurra fuera del agua. Este trabajo resume información sobre el ciclo de vida del anuro Batrachyla taeniata, especie conocida como rana de ceja corta, que se reproduce desde mediados del verano hasta mediados del otoño, colocando sus huevos en el suelo húmedo inundable de los bosques donde éstos se incuban. Particularmente, nuestros estudios se llevaron a cabo en el bosque del Parque Municipal Llao Llao, donde la especie habita diferentes ambientes acuáticos. Los renacuajos eclosionan cuando las lluvias otoñales producen el ascenso del nivel de agua o durante la inundación de un humedal, en un estado de desarrollo que les permite alimentarse inmediatamente y continuar su crecimiento en el agua a muy bajas temperaturas durante varios meses antes del arribo de la primavera. A través de observaciones de campo y de la incubación de huevos en condiciones de laboratorio, pudimos determinar la alta dependencia que existe entre las precipitaciones, la temperatura y el desarrollo efectivo de los huevos y su posterior eclosión. Finalmente, señalamos los potenciales efectos del cambio climático a escala regional y cómo este fenómeno podría afectar la supervivencia de esta especie común de los bosques húmedos del Parque Nacional Nahuel Huapi.; Anuran amphibians of the Andean-Patagonian forest show a wide variety of adaptations to different aquatic environments and regional environmental conditions. These adaptations include particularities in their life cycles, such as that all or most of the cycle occur out of water. This work summarizes information about the life cycle of the anuran Batrachyla taeniata, or banded wood frog, which reproduces from midsummer to midautumn, laying eggs out of the water, in the moist soil, where they are incubated. Particularly our studies were carried out in the forest of the Llao Llao Municipal Park, where the species lives in different aquatic environments. Tadpoles hatch when autumn rains cause an increase in water level or during flooding of a wetland, in a state of development that allows them to feed immediately and continue their growth in the water at low temperatures for several months before arrival of spring. Through field observations and incubation of eggs under laboratory conditions we were able to determine the high dependence that exists between precipitation, temperature and the effective development of eggs and their subsequent hatching. Finally, we point out the potential effects of climate change on a regional scale and how this phenomenon could affect the survival of this common species of rainforests of the Nahuel Huapi National Park.

The evolution of the axial skeleton intercentrum system in snakes revealed by new data from the Cretaceous snakes Dinilysia and Najash Garberoglio, Fernando Fabio; Gómez, Raúl Albero; Simões, Tiago R.; Caldwell, Michael Wayne; Apesteguía, Sebastián Snakes are an extremely modifed and long-lived clade of lizards that have either lost or highly altered many of the synapomorphies that would clearly link them to their closest sister-group among squamates. We focus here on one postcranial morphological complex, the intercentrum system which in most non-ophidian squamates is limited to the cervical and caudal regions. The Cervical Intercentrum System (CeIS) is composed of a single intercentral element that sometimes articulates with a ventral projection (hypapophyses) of the centrum; the Caudal Intercentrum System (CaIS) is formed by an intercentral element, the haemal arch/chevron bone, and paired ventral projections of the centrum, the haemapophyses. In modern snakes, the intercentrum element of the CeIS is considered lost or fused to the hypaphophysis, and the chevron bone in CaIS is considered lost. Here, we describe new specimens of the early snake Dinilysia patagonica, and reinterpret previously known specimens of Dinilysia and Najash rionegrina, that do not show the expected snake morphology. The anatomy of these fossil taxa unambiguously shows that free cervical and caudal intercentra attached to distinct downgrowths (hypapophyses and haemapophyses) of the centra, are present in basal fossil snakes, and agrees with the proposed loss of post atlas-axis intercentra in later evolving snakes.

A new specimen with skull and vertebrae of Najash rionegrina (Lepidosauria: Ophidia) from the early Late Cretaceous of Patagonia Garberoglio, Fernando Fabio; Gomez, Raul Orencio; Apesteguía, Sebastián; Caldwell, Michael Wayne; Sánchez, María L.; Veiga, Gonzalo Diego The limbed snake Najash rionegrina from the Cenomanian (early Late Cretaceous) of the La Buitrera Palaeontological Area (LBPA), northern Patagonia is a key taxon in any study of the origin and early evolution of snakes. The original concept of the taxon was based on the holotype and a number of referred specimens including an isolated partial skull; a conservative rebuttal argued this concept was too broad due to the lack of association between the holotype elements and the referred specimens. Here we describe a new snake specimen consisting of a partial skull and closely associated vertebrae from the La Buitrera Locality, one of many productive snake localities within the LBPA. The analysis of the vertebrae of the new specimen identifies distinct features shared with the vertebrae of the N. rionegrina holotype; the partial skull of the new specimen is also identical to the partial skull that formed part of the original concept of N. rionegrina. Phylogenetic analysis, using data from the type and referred specimens, and new materials described here, reconstructs N. rionegrina as a basal snake in a ?madtsoiid? clade outside of crown-group Serpentes. These new morphologies, and autapomorphies recognized in character analyses, permit the construction of a new and expanded diagnosis of N. rionegrina.

Silver Nanoparticle-Based Arrays into Mesoporous Thin Films Structures for Photoelectronic Circuits Delgado, Diana Catherine; Di Donato, Andrés Leonardo; Catalano, Paolo Nicolás; Bellino, Gabriel Martín Background: Silver nanosystems have attracted considerable attention for numerous applications in optoelectronics. The localized surface plasmon of silver nanoparticles embedded into mesoporous titania gives rise to an enhancement of local optical field in the vicinity of Ag nanoparticles which act as efficient light-trapping components, resulting in a visible wavelength-dependent photocurrent. Objective: In this paper, we synthetized patterned nanocomposites formed by titania mesoporous thin films loaded with alkanethiol functionalized Ag nanoparticles and we demonstrated that these stable and accessible nanostructures possess a photocurrent response. Method: Mesoporous thin films are created by combining sol-gel synthesis and template selfassembly. Based on a photolithography technique, silver nanoparticles were selectively photodeposited and then stabilized with octanethiols. Current vs. voltage curves with and without light were compared, where selective light wavelength measurements were achieved by using visible bandpass filters. The optofluidic behavior was evaluated by placing a drop of solutions on the mesoporous film. Results: We demonstrate photocurrent in these mesoporous thin film structures decorated with chemistabilized Ag nanoparticle-based conductive arrays, with significantly enhanced photocurrent peak at the plasmon resonant wavelength around 540 nm. Our findings offer a possibility to perform improved fluid detection with silver-mesoporous titania electronic devices. Conclusion: We showed that an optofluidic sensitive nanocomposite circuit consisting of alkanethiol-functionalized metal nanoparticles embedded in a mesoporous oxide thin film matrix can be produced.

A penalized time-frequency band feature selection and classification procedure for improved motor intention decoding in multichannel EEG Peterson, Victoria; Wyser, Dominik; Lambercy, Olivier; Spies, Ruben Daniel; Gassert, Roger Objective. Motor imagery brain-computer interfaces (MI-BCIs) based on electroencephalography (EEG), a promising technology to provide assistance and support rehabilitation of neurological patients with sensorimotor impairments, require a reliable and adaptable subject-specific model to efficiently decode motor intention. The most popular EEG feature extraction algorithm for MI-BCIs is the common spatial patterns (CSP) method, but its performance strongly depends on the predefined frequency band and time segment length for analyzing the EEG signal. Approach. In this work, a novel method for efficiently decoding motor intention for EEG-based BCIs performing multiple frequency band analysis in multiple EEG segments is presented. This decoding algorithm uses raw multichannel EEG data which are decomposed into specific temporal and frequency bands. Features are extracted at each - band by using CSP. Feature selection and classification are simultaneously performed by means of a fast procedure, based on elastic-net regression, which allows for the inclusion of a priori discriminative information into the model. The effectiveness of the proposed method is tested off-line on two public EEG-based MI-BCI datasets and on a self-acquired dataset in two configurations: multiple temporal windows and single temporal window. Main results. The experimental results show that the proposed multiple time-frequency band method yields overall accuracy improvements of up to (average accuracy of 84.8%) as compared to the best current state-of-the-art methods based on filter bank analysis and CSP for MI detection. Also, classification variability is reduced, making the proposed method more robust to intra-subject EEG fluctuations. Significance. This paper presents a novel approach for improving motor intention detection by automatically selecting subject-specific spatio-temporal-spectral features, especially when MI has to be detected against rest condition. This technique contributes to the further advancement and application of EEG-based MI-BCIs for assistance and neurorehabilitation therapy.

Sexual selection and inbreeding: Two efficient ways to limit the accumulation of deleterious mutations Noël, Elsa; Fruitet, Elise; Lelaurin, Dennyss; Bonel, Nicolás; Ségard, Adeline; Sarda, Violette; Jarne, Philippe; David, Patrice Theory and empirical data showed that two processes can boost selection against deleterious mutations, thus facilitating the purging of the mutation load: inbreeding, by exposing recessive deleterious alleles to selection in homozygous form, and sexual selection, by enhancing the relative reproductive success of males with small mutation loads. These processes tend to be mutually exclusive because sexual selection is reduced under mating systems that promote inbreeding, such as self‐fertilization in hermaphrodites. We estimated the relative efficiency of inbreeding and sexual selection at purging the genetic load, using 50 generations of experimental evolution, in a hermaphroditic snail (Physa acuta). To this end, we generated lines that were exposed to various intensities of inbreeding, sexual selection (on the male function), and nonsexual selection (on the female function). We measured how these regimes affected the mutation load, quantified through the survival of outcrossed and selfed juveniles. We found that juvenile survival strongly decreased in outbred lines with reduced male selection, but not when female selection was relaxed, showing that male‐specific sexual selection does purge deleterious mutations. However, in lines exposed to inbreeding, where sexual selection was also relaxed, survival did not decrease, and even increased for self‐fertilized juveniles, showing that purging through inbreeding can compensate for the absence of sexual selection. Our results point to the further question of whether a mixed strategy combining the advantages of both mechanisms of genetic purging could be evolutionary stable.

Fosfomycin in vivo penetration in swine intestinal cells Pérez, Denisa Soledad; Martínez, Guadalupe; Fernández Paggi, María Belén; Decundo, Julieta María; Romanelli, Agustina; Mozo, Joaquín; Dieguez, Susana Nelly; Soraci, Alejandro Luis Enteric diseases have a high economic impact on animal production, being the interstitial and intracellular fluids, the main sites of infection (biophase) of the pathogens responsible for these disorders. Fosfomycin is an antibiotic widely used for the treatment and prevention of swine infections caused by resistant bacteria. For most of the important pathogens in swine production, fosfomycin MIC90 has been established in 0.25-4 µg/mL. Calcium fosfomycin concentrations in swine intestinal cells were previously determined by in vitro and ex vivo studies, although, still now, there are no in vivo studies showing the exposure of minimum inhibitory concentrations of fosfomycin in the enteric infectious site. According to this background, the aim of this research was to determine in vivo calcium fosfomycin concentrations on swine intestinal cells. Four clinically healthy post-weaning piglets 4-5 weeks old were used. Animals were sacrificed after 15 days of calcium fosfomycin consumption in the drinking water (30 mg/kg). After slaughtering, jejunum was removed. Intracellular concentrations of the antibiotic were analyzed by HPLC MS/MS and they ranged from 0.82 to 2.05 µg/mL. These concentrations exceed the MIC90 of intestinal pathogens such as E.coli (0.5 μg/mL), although they are lower than the MIC90 of Salmonella enterica (4 μg/mL).

Encapsulation of fish oil in soybean protein particles by emulsification and spray drying Di Giorgio, Luciana; Salgado, Pablo Rodrigo; Mauri, Adriana Noemi This manuscript reports a systematic study of encapsulation of fish oil into soybean microparticles by emulsification and subsequent spray drying in order to protect it from lipid autoxidation and/or facilitate its handling for incorporation into healthy food products. In particular, the effect of the formulation and the emulsification technique on the physicochemical properties of the resulting emulsions and encapsulates was evaluated. Two emulsifying processes and four protein:oil ratios were analyzed. Soy proteins managed to encapsulate the fish oil, masking its characteristic odor and its oily texture into matrix type microcapsules, as was observed by confocal microscopy. The emulsification process was determinant in the efficiency of drying and encapsulation as well as in the protection exerted on the oil oxidative stability. Although both, emulsifying and drying processes caused certain initial oil oxidation (verified by peroxide and TBA indexes), some of the studied systems showed a good perspective of oxidative stability over time (studied by accelerated rancimat test).

A multi-substrate screening approach for the identification of a broadly applicable Diels-Alder catalyst Kim, Hyejin; Gerosa, Gabriela Guillermina; Aronow, Jonas; Kasaplar, Pinar; Ouyang, Jie; Lingnau, Julia B.; Guerry, Paul; Farès, Christophe; List, Benjamin When developing a synthetic methodology, chemists generally optimize a single substrate and then explore the substrate scope of their method. This approach has led to innumerable and widely-used chemical reactions. However, it frequently provides methods that only work on model substrate-like compounds. Perhaps worse, reaction conditions that would enable the conversion of other substrates may be missed. We now show that a different approach, originally proposed by Kagan, in which a collection of structurally distinct substrates are evaluated in a single reaction vessel, can not only provide information on the substrate scope at a much earlier stage in methodology development, but even lead to a broadly applicable synthetic methodology. Using this multi-substrate screening approach, we have identified an efficient and stereoselective imidodiphosphorimidate organocatalyst for scalable Diels?Alder reactions of cyclopentadiene with different classes of α,β-unsaturated aldehydes.

Antecedentes de conservación y turismo en áreas naturales protegidas provinciales de Río Negro (Argentina); Conservation and tourism background in protected natural areas of Río Negro (Argentina) province Vejsbjerg, Laila El objetivo fue identificar los cambios en el tiempo del concepto de conservación y el rol del turismo en áreas naturales protegidas (ANPs), bajo jurisdicción yadministración de la provincia de Río Negro. Como resultado se diferenciaroncinco sub-períodos. Se concluyó: 1) En las zonas turísticas atlántica y andina lasANPs se integraron a proyectos turísticos intra e inter provinciales, aunque lasANPs de las zonas Alto Valle y Línea Sur tienen una escasa integración a circuitosextra-locales y su rol no es claro en el territorio del turismo; 2) Si bien endependencias provinciales de Ambiente ha habido una tendencia hacia una gobernanza estatal con co-manejo en el sector turístico privado existe un bajonivel de conocimiento de estas ANPs.; The aim was to identify changes over time regarding the notion of conservation and the role that tourism plays in natural protected areas (NPAs) under the jurisdiction and administration of the Río Negro province. As a result, five periods were differentiated. It was concluded that: 1) in the Atlantic and Andean tourist zones, NPAs are integrated with intra- and inter-provincial tourism projects, although the NPAs of Alto Valle and Línea Sur areas have little integration with extra-local circuits, and their role is not clear in the tourism territory; 2) while there has been a tendency towards state governance with co-management in provincial environmental departments in the private tourist sector has a low level of knowledge of these NPAs.

The role of an invader in its native range: could differential grazing by apple snails structure the submersed macrophytes assemblages in Southern Pampas (Argentina)? Manara, Enzo; Maldonado, Mara Anahí; Martín, Pablo Rafael Apple snails are renowned for their strong impacts on aquatic vegetation and ecosystem function in invaded regions but the existing knowledge on their role in aquatic ecosystems and communities in their native range is scarce. The variation in palatability of five submersed macrophytes, the preference of Pomacea canaliculata for them and the potential effects of its differential grazing on macrophyte assemblages in Southern Pampas were investigated. In no-choice trials, macrophytes showed differences in palatability that were correlated to physical defences and not to nutritional values. In free-choice trials, preference was consistent with the palatability ranking. In a mesocosms experiment, Chara contraria and Zannichellia palustris were totally eradicated by apple snails, the coverage of Stuckenia striata increased only when they were absent and Ludwigia peploides and Myriophyllum quitense were not affected. The live biomass of Z. palustris, S. striata and M. quitense was reduced by apple snails. Total live and dead biomasses were lower, and chlorophyll-a concentrations higher, in the mesocosms with apple snails. Our results indicate that P. canaliculata has a keystone role in its native range and that its differential grazing could shape the structure and composition of submersed vegetation and promote shifts to turbid-water states or maintain them.

Modern plains vizcacha (Lagostomus maximus, Chinchillidae, Rodentia) as a bone accumulating agent in the Argentine Pampas: Application to the study of fossiliferous sites Tomassini, Rodrigo Leandro; Montalvo, Claudia Inés; Fernández Jalvo, Yolanda; Garrone, Mariana Carolina; Kin, Marta Susana Lagostomus maximus (Rodentia, Chinchillidae), or Plains vizcacha, is a caviomorph rodent that inhabits semi-arid grasslands and desert scrub of central and northern Argentina, southern Paraguay and southeastern Bolivia. A particular behavior of the Plains vizcacha is the collection and transport of bones, dried dung and branches, among other objects, which are accumulated near the vizcacheras entrances. A bone concentration, originated in active vizcacheras of the southwestern Buenos Aires Province (Argentina), was studied from a taphonomic point of view for one year. The obtained results reflect that Plains vizcacha represents an important bone accumulating agent in the Argentine Pampas, and it is capable of producing large concentrations. Moreover, their vizcacheras act as natural traps that may favor the accumulation and preservation of the bone remains. The information obtained through this actualistic study provides new information on the ecology of this rodent and, in turn, introduces a framework of reference for the identification of similar concentrations in the fossil record.

Statistics of incompressible hydrodynamic turbulence: An alternative approach Andrés, Nahuel; Banerjee, Supratik Using a recent alternative form of the Kolmogorov-Monin exact relation for fully developed hydrodynamics (HD) turbulence, the incompressible energy cascade rate is computed. Under this current theoretical framework, for three-dimensional (3D) freely decaying homogeneous turbulence, the statistical properties of the fluid velocity (u), vorticity (ω= ×u), and Lamb vector (L=ω×u) are numerically studied. For different spatial resolutions, the numerical results show that can be obtained directly as the simple products of two-point increments of u and L, without the assumption of isotropy. Finally, the results for the largest spatial resolutions show a clear agreement with the cascade rates computed from the classical four-thirds law for isotropic homogeneous HD turbulence.

Zeta potential changes of Saccharomyces cerevisiae during fermentative and respiratory cycles Lavaisse, Lucía María; Hollmann, Axel; Nazareno, Mónica Azucena; Disalvo, Edgardo Anibal Saccharomyces cerevisiae is a type of yeast, widely used in diverse biotechnological food-beverage processes. Although the performance of an industrial fermentation process depends largely on the number of cells, it is necessary to consider the physiological state of the cultures. In this context, the aim of this study was to determine in a yeast culture how factors such as growth conditions affect surface properties at the different growth stages. Our results show that, S. cerevisiae spp. exhibits different zeta potential mean values along the exponential, post-diauxic and stationary growth phases. In addition, there were differences depending on whether they are in aerobic or anaerobic conditions. When the effect of pH on the media was studied, a different dependence of zeta potential at each stage reveals that in the living cells the surface potential depends on the interaction between secreted acids and the constituents of the surfaces, according to the growth conditions. In order to have a view at the cellular level, the zeta potential on individual cells by optical microscopy has been determined at different stages of culture in aerobic and anaerobic conditions. This single-cell method allows for the identification and following of the development of different cell subpopulations during each growth stage. Furthermore, the behavior of the dead cells provided evidence to relate the large negatively charged population with cell wall damage. Overall, the results obtained in the present work represent an important milestone for a novel application of zeta potential technique on yeast.

Retrieving shallow shear-wave velocity profiles from 2D seismic-reflection data with severely aliased surface waves Onnis, Luciano Emanuel; Osella, Ana Maria; Carcione, Jose M. The inversion of surface-wave phase-velocity dispersion curves provides a reliable method to derive near-surface shear-wave velocity profiles. In this work, we invert phase-velocity dispersion curves estimated from 2D seismic-reflection data. These data cannot be used to image the first 50 m with seismic-reflection processing techniques due to the presence of indistinct first breaks and significant NMO-stretching of the shallow reflections. A surface-wave analysis was proposed to derive information about the near surface in order to complement the seismic-reflection stacked sections, which are satisfactory for depths between 50 and 700 m. In order to perform the analysis, we had to overcome some problems, such as the short acquisition time and the large receiver spacing, which resulted in severe spatial aliasing. The analysis consists of spatial partitioning of each line in segments, picking of the phase-velocity dispersion curves for each segment in the f-k domain, and inversion of the picked curves using the neighborhood algorithm. The spatial aliasing is successfully circumvented by continuously tracking the surface-wave modal curves in the f-k domain. This enables us to sample the curves up to a frequency of 40 Hz, even though most components beyond 10 Hz are spatially aliased. The inverted 2D VS sections feature smooth horizontal layers, and a sensitivity analysis yields a penetration depth of 20–25 m. The results suggest that long profiles may be more efficiently surveyed by using a large receiver separation and dealing with the spatial aliasing in the described way, rather than ensuring that no spatially aliased surface waves are acquired.

Long-term changes on estuarine ciliates linked with modifications on wind patterns and water turbidity López Abbate, María Celeste; Molinero, Juan Carlos; Perillo, Gerardo Miguel E.; Barria, Maria Sonia; Pettigrosso, Rosa Elsa; Guinder, Valeria Ana; Uibrig, Román Armando; Berasategui, Anabela Anhi; Vitale, Alejandro José; Marcovecchio, Jorge Eduardo; Hoffmeyer, Monica Susana Planktonic ciliates constitute a fundamental component among microzooplankton and play a prominent role in carbon transport at the base of marine food webs. How these organisms respond to shifting environmental regimes is unclear and constitutes a current challenge under global ocean changes. Here we examine a multiannual field survey covering 25 years in the Bahía Blanca Estuary (Argentina), a shallow, flood-plain system dominated by wind and tidal energy. We found that the estuary experienced marked changes in wind dominant regimes and an increase in water turbidity driven from the joint effect of persistent long-fetch winds and the indirect effect of the Southern Annular Mode. Along with these changes, we found that zooplankton components, i.e. ciliates and the dominant estuarine copepod Acartia tonsa, showed a negative trend during the period 1986–2011. We showed that the combined effects of wind and turbidity with other environmental variables (chlorophyll, salinity and nutrients) consistently explained the variability of observed shifts. Tintinnids were more vulnerable to wind patterns and turbidity while showed a loss of synchrony with primary productivity. Water turbidity produced a dome-like pattern on tintinnids, oligotrichs and A. tonsa, implying that the highest abundance of organisms occurred under moderate values (∼50 NTU) of turbidity. In contrast, the response to wind patterns was not generalizable probably owing to species-specific traits. Observed trends denote that wind-induced processes in shallow ecosystems with internal sources of suspended sediments, are essential on ciliate dynamics and that such effects can propagate trough the interannual variability of copepods.

Optimization of bromelain isolation from pineapple byproducts by polysaccharide complex formation Campos, Débora A.; Coscueta, Ezequiel Ricardo; Woitovich Valetti, Nadia; Pastrana Castro, Lorenzo M.; Domínguez Teixeira, José Mario; Picó, Guillermo Alfredo; Pintado, Maria Manuela A simple method for bromelain extraction from industrial pineapple residues (stems and peels) was developed and optimized through factorial experimental design. The developed methodology, based on precipitation with carrageenan, represents an alternative to the use of organic solvents and inorganic salts (common industrial precipitation) and allows achieving extracts with high bromelain purity. High recovery yield – 80–90% - of active bromelain was obtained for both crude juices (stems and peels) making possible to obtain ca. 0.3 g of bromelain from 100 g of pineapple byproducts using a low polysaccharide concentration (0.2–0.3% w/v).

Thymol supplementation effects on adrenocortical, immune and biochemical variables recovery in Japanese quail after exposure to chronic heat stress Nazar, Franco Nicolas; Videla, Emiliano Ariel; Marin, Raul Hector Chronic heat stress (CHS) exposure negatively impairs avian' immunoneuroendocrine interplay. Thymol has shown several bioactive properties including antioxidant, bactericidal, antifungal and gamma-aminobutyric acid modulator activities. Indeed, supplementation with thymol has been used with positive effects on poultry production and immune-related variables. This study evaluates whether a thymol dietary supplementation can be used as a new functional feed strategy to mitigate CHS deleterious effects on endocrine, biochemical and immune-related variables. Starting at 100 days of age, 24 fully adult Japanese quail were fed with a diet supplemented with thymol (≈80 mg/quail per day) and other 24 quail remained non-supplemented (control diet). Between 119 and 127 days of age, half of the quail within those groups were submitted to a CHS by increasing environmental temperature from 24°C to 34°C during the light phase and the other half remained at 24°C (non-stressed controls). A period of 3 days after CHS ended (during the recovery period), corticosterone, albumin, total proteins and globulins and glucose concentrations, inflammatory response, antibody production and heterophil to lymphocyte (H/L) ratio were assessed. No differences between groups were found in basal corticosterone concentrations. Total proteins, total globulins and glucose concentrations were found elevated in the previously CHS group compared with their control counterparts. Regardless of the previous CHS exposure, thymol supplementation increased albumin concentrations and inflammatory responses and decreased antibody titers. An interaction between thymol supplementation and prior CHS exposure was found on the H/L ratio. Quail previously exposed to CHS and supplemented with thymol showed similar H/L values than their control non-stressed counterparts, suggesting that thymol has a stress preventive effect on this variable. The present findings together with the already reported thymol bioactive properties, suggest that feed supplementation with this compound could be a useful strategy to help overcoming some of the CHS induced alterations.

The effect of a saturated kink on the dynamics of tungsten impurities in the plasma core Ferrari, Hugo Emilio; Farengo, Ricardo; Clauser, Cesar Fernando We studied the effect of saturated kink like instabilities on the redistribution of W impurities. A numerical code that follows the exact trajectories of the impurity ions in the total fields and includes collisions was employed. The code is written in CUDA C and runs in graphical processing units, allowing simulations with a large number of particles with modest resources.The total electric and magnetic fields are calculated as the sum of a simple analytical equilibrium (large aspect ratio, circular cross section) plus the fields of the kink mode. Our simulations show that when the W ions have a thermal velocity distribution, with zero mean velocity, the kink hasno effect on the W density. However, when we include the plasma rotation and the drag on the impurities, the kink can affect the W density. When the average passing frequency of the W ions is similar to the frequency of the kink mode, the expulsion of W ions from the plasma core is maximum and the W density profile shows a hollow structure. This could have implications for the mitigation of W accumulation.