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Antarctic benthic communities are largely structured by predation, which leads to the development of mechanisms of repellence. Among those mechanisms, chemical defences are quite extensive, yet poorly understood. To increase knowledge about the role of chemical defences in the Southern Ocean ecosystems, we assessed the incidence of feeding repellents in sessile and vagile invertebrates from nine phyla: Porifera, Cnidaria, Nemertea, Annelida, Mollusca, Bryozoa, Echinodermata, Hemichordata, and Tunicata (Ascidiacea). Samples were collected at depths of 120–789 m in the eastern Weddell Sea and Bouvet Island, and at depths ranging 0–100 m in the South Shetland Islands. When possible, specimens were dissected to study anatomical allocation of repellents. The common, eurybathic sea star Odontaster validus was chosen to perform feeding repellence bioassays, using diethyl ether (lipophilic) and butanol (hydrophilic) extracts from these samples. Among the 75 species tested, 52 % were studied for the first time for anti-predatory properties. Results provide further evidence of the prevalence of defensive metabolites in Antarctic organisms, with 47 % of the species exhibiting significant repellence within their lipophilic extracts. They also suggest a wider use of nonpolar defensive chemicals. Sessile taxa displayed highest repellence activities, with ascidians, cnidarians, and sponges being the most chemically protected. Overall, the present study indicates that natural products by mediating trophic interactions between prey and their potential predators play an important role in structuring Antarctic benthic ecosystems., SI

Taking into account the broad biological activities found in the meridianin indole alkaloids isolated to date, we have re-examined the organic extracts of an Antarctic collection of the tunicates Aplidium meridianum and A. falklandicum (Chordata: Ascidiacea) by HPLC in conjunction with a high-resolution mass spectrometer (HPLC-MS). A new set of analogs of meridianins A–G has been detected, and their structures are proposed on the basis of the molecular formulae identified by LC-HRMS analysis using a C18 column with a gradient of water/acetonitrile and an LTQ-FT-MS Orbitrap detector. Remarkably, dimers derived from meridianin A and from meridianin B or E were also detected. Our findings provide further evidence of the broad variability within the meridianin-like derivatives of this highly bioactive alkaloid family. Copyright © 2015 John Wiley & Sons, Ltd.

Warming oceans menace reef ecosystems by disrupting symbiosis between cnidarians and Symbiodinium zooxanthellae, thus triggering bleach episodes. Temperature fluctuations promote adjustments in physiological variables and symbiont composition, which can cause stress responses, but can also yield adaptation if fitter host–symbiont homeostasis are achieved. To understand such processes manipulative studies are required, but many reef-building cnidarians pose limitations to experimental prospects. We exposed Exaiptasia anemones to Gradual Thermal Stress (GTS) and Heat Shock (HS) exposures and monitored chlorophyll and symbiont dynamics to test the phenotypic plasticity of these photosynthetic holobionts. GTS enhanced chlorophyll concentrations and decreased Symbiodinium proliferation. A recovery period after GTS returned chlorophyll to lower concentrations and symbiont divisions to higher rates. HS triggered a stress response characterized by intense symbiont declines through degradation and expulsion, algal compensatory proliferation, and chlorophyll accumulation. Anemones pre-exposed to GTS displayed more acute signs of symbiont paucity after HS, demonstrating that recurrent stress does not always induce bleaching-resistance. Our study is the first documenting Symbiodinium C and D, along with the predominant Clade B1 in Exaiptasia anemones. C subclades found in outdoor specimens faded under laboratory exposures. Clade D emerged after HS treatments, and especially after GTS pre-exposure. This highlights the thermotolerance of D subclades found in E. pallida and shows that bleaching-recovery can involve shifts of background symbiont phylotypes. This study enlightens the capability of Exaiptasia anemones to acclimate to gradually increased temperatures, and explores into how thermal history influences in subsequent stress tolerance in symbiotic cnidarians.

Background: Ageing is associated with sensory and physical declines and falling risk. Objective: To determine the association between 3 performance-based mobility tests and fall history. Methods: Fifty participants' mobility was assessed by Timed Up and Go (TUG) and 4- and 6-m walking tests (WT). Results: The TUG performance correlated with 4- and 6-m WT performance, and performance on 4-m WT positively correlated with 6-m WT. Only TUG performance showed a strong relationship to fall history. Conclusions: Performance tests could indicate the presence of fall history in the institutionalized older adults; the TUG being the most suitable compared with other common WT.

Many bioactive products from benthic invertebrates mediating ecological interactions have proved to reduce predation, but their mechanisms of action, and their molecular identities, are usually unknown. It was suggested, yet scarcely investigated, that nutritional quality interferes with defensive metabolites. This means that antifeedants would be less effective when combined with energetically rich prey, and that higher amounts of defensive compounds would be needed for predator avoidance. We evaluated the effects of five types of repellents obtained from Antarctic invertebrates, in combination with diets of different energetic values. The compounds came from soft corals, ascidians and hexactinellid sponges; they included wax esters, alkaloids, a meroterpenoid, a steroid, and the recently described organic acid, glassponsine. Feeding repellency was tested through preference assays by preparing diets (alginate pearls) combining different energetic content and inorganic material. Experimental diets contained various concentrations of each repellent product, and were offered along with control compound-free pearls, to the Antarctic omnivore amphipod Cheirimedon femoratus. Meridianin alkaloids were the most active repellents, and wax esters were the least active when combined with foods of distinct energetic content. Our data show that levels of repellency vary for each compound, and that they perform differently when mixed with distinct assay foods. The natural products that interacted the most with energetic content were those occurring in nature at higher concentrations. The bioactivity of the remaining metabolites tested was found to depend on a threshold concentration, enough to elicit feeding repellence, independently from nutritional quality.

The role of bioactive metabolites in ecological interactions involving Antarctic bryozoans has been scarcely studied. Bryozoans are one of the most abundant and diverse members of the Antarctic benthos and are preyed upon by diverse kinds of predators. They seem to be casual food items of the common Antarctic sea urchin Sterechinus neumayeri and the ubiquitous omnivorous amphipod Cheirimedon femoratus. In this study, the cytotoxic activity against embryos and sperm of the sea urchin S. neumayeri and the substrate preferences of the amphipod C. femoratus were assessed using organic extracts from Antarctic bryozoans, in order to determine the presence of chemical defenses. New adapted protocols were designed using a solidifying gel for simulating bryozoans’ surface. We analyzed 32 organic extracts from 16 samples that belonged to 13 different bryozoan species. No cytotoxicity was detected against embryos of S. neumayeri, while 12 of the 13 bryozoan species were cytotoxic to sperm at natural concentrations. In the substrate preference assays, the amphipod C. femoratus was repelled by ten species. The variable bioactivities found in both types of organic partitions of extracts indicated the presence of both lipophilic and hydrophilic defenses. Inter- and intraspecific variability of chemical defenses was detected also, suggesting environmental-induced responses, symbiotic production, and/or genetic variability. Possible alternative defensive mechanisms are also discussed for species with low or no chemical defense. Our results clearly support the fact that chemically mediated bioactivity in Antarctic bryozoans is common, and there is a likely ecological role of cytotoxic and repellent compounds for their protection.

Background: studies conducted in animal models and humans suggest the presence of a dynamic equilibrium of amyloid-β (Aβ) peptide between cerebrospinal fluid (CSF) and plasma compartments. Objective: to determine whether plasma exchange (PE) with albumin replacement was able to modify Aβ concentrations in CSF and plasma as well as to improve cognition in patients with mild-moderate Alzheimer's disease (AD). Methods: in a multicenter, randomized, patient- and rater-blind, controlled, parallel-group, phase II study, 42 AD patients were assigned (1 : 1) to PE treatment or control (sham) groups. Treated patients received a maximum of 18 PE with 5% albumin (Albutein®, Grifols) with three different schedules: two PE/weekly (three weeks), one PE/weekly (six weeks), and one PE/bi- weekly (12 weeks), plus a six-month follow-up period. Plasma and CSF Aβ1-40 and Aβ1-42 levels, as well as cognitive, functional, and behavioral measures were determined. Results: CSF Aβ1-42 levels after the last PE compared to baseline were marginally higher in PE-treated group versus controls (adjusted means of variation: 75.3 versus -45.5 pg/mL; 95% CI: -19.8, 170.5 versus 135.1, 44.2; p = 0.072). Plasma Aβ1-42 levels were lower in the PE-treated group after each treatment period (p

Alcyonacean soft corals lack physical or skeletal defenses and their nematocyst system is weak, leading to the conclusion that soft corals mainly rely on chemistry for protection from predators and microbes. Defensive chemicals of primary and secondary metabolic origin are exuded in the mucus surface layer, explaining the general lack of heavy fouling and predation in corals. In Antarctic ecosystems, where generalist predation is intense and mainly driven by invertebrate consumers, the genus Alcyonium is represented by eight species. Our goal was to investigate the understudied chemical ecology of Antarctic Alcyonium soft corals. We obtained six samples belonging to five species: A. antarcticum, A. grandis, A. haddoni, A. paucilobulatum, and A. roseum, and assessed the lipid-soluble fractions for the presence of defensive agents in these specimens. Ethyl ether extracts were tested in feeding bioassays with the sea star Odontaster validus and the amphipod Cheirimedon femoratus as putative sympatric predators. Repellent activities were observed towards both consumers in all but one of the samples assessed. Moreover, three of the extracts caused inhibition to a sympatric marine bacterium. The ether extracts afforded characteristic illudalane sesquiterpenoids in two of the samples, as well as particular wax esters subfractions in all the colonies analyzed. Both kinds of metabolites displayed significant deterrent activities demonstrating their likely defensive role. These results suggest that lipophilic chemicals are a first line protection strategy in Antarctic Alcyonium soft corals against predation and bacterial fouling.

Clinical research [Abstract] BACKGROUND: The person with dementia should be treated as an unique person regarding symptoms directly associated with dementia, such as problems with memory, hallucinations, and delusions, as well as other physical, mental, or neurological deficits. The symptoms not directly typical of dementia, such as musculoskeletal disorders or depression, should be also be considered in order to improve the quality of life of a person with dementia. That is why professional caregivers have to broaden their current knowledge not only of medical symptoms but also of the patient’s psychosocial condition and increase their inquisitiveness about the individual condition of the patient. The aim of the study was to get to know the opinion of professional caregivers about the UnderstAID platform and its usefulness for informal caregivers. MATERIAL AND METHODS: Participants in the study group consisted of professional caregivers: nurses, sociologists, psychologists, physiotherapists, and occupational therapists, all of whom specialized in geriatrics and had experience in working with people with dementia. All professional caregivers answered 24 questions that refer to positive and negative aspects of the UnderstAID platform. RESULTS: The study group of professional caregivers highly appreciated that the application could give support to caregivers (mean score of 4.78; 5 points means that they totally agreed, and 1 point means that they totally disagreed) and that a wide range of multimedia materials helped the informal caregivers to gain a better understanding of the contents (mean score of 4.78). There was a statistically significant correlation between the age of the professional caregivers and the frequency of positive opinions that the UnderstAID application gave support to caregivers of relatives with dementia (p=0.028) and the opinion that videos, photos, and pictures may help the informal caregivers to gain a better understanding of the contents (p=0.028). CONCLUSIONS: A group of professional caregivers positively assessed the UnderstAID platform. Caregivers, especially older caregivers, highly appreciated the usefulness of videos, photos, and pictures for gaining a better understanding of the contents. European Commission; AAL5/1/2013 European Commission; AAL5/2/2013

Antarctic and sub-Antarctic benthic invertebrates are subjected to intense predation by mobile macroinvertebrates. Accordingly, chemical protection as well as other defensive mechanisms are expected to be common in organisms inhabiting these ecosystems. In order to evaluate anti-predation activities and allocation of chemical defenses within the anatomy of marine benthic Antarctic and sub-Antarctic invertebrates, 55 species were tested for feeding repellence against the sea star Odontaster validus, a common eurybathic sympatric predator. The invertebrates tested were collected from the deep waters of two poorly surveyed areas in terms of chemical ecology studies: the eastern Weddell Sea (Antarctica) and the vicinities of Bouvet Island (sub-Antarctica). Experiments were conducted at the Spanish Antarctic Base in Deception Island. In the feeding deterrence experiments, shrimp pieces were treated with crude lipophilic fractions obtained from each species, and were offered to the sea stars. A total of 29 species (53 %) from 7 different phyla (Porifera, Cnidaria, Chordata, Bryozoa, Echinodermata, Mollusca, and Annelida) showed feeding repellence against O. validus, and are therefore chemically protected against this keystone predator. Furthermore, 25 species were dissected into parts to investigate the possible allocation of defensive compounds. Some of the results obtained from these analyses support the prediction that the most exposed/vulnerable tissues concentrate chemical defenses to avoid predation against the sea stars. In summary, the results obtained in our survey support the hypothesis that deep-water Antarctic and sub-Antarctic benthic invertebrates are well protected chemically against sympatric predators, similarly to what has been reported in previous studies investigating shallow-water Antarctic species.

Table S1. Species names and dissected body-regions of the samples used to obtain extracts for feeding assays. WW: sample wet weight; DW: sample dry weight; EE: dry weight of the diethyl ether extract; NEE: percentage of the natural tissue concentration of EE in the sample calculated by dividing EE by DW; na: not available; body-regions — BAS: basal, API: apical, EXT: external, INT: internal, POL: polyparium, AX: axis body-parts; morphotypes — BW numbers after species names indicate conspecific samples from different collection sites

The chemical analysis of the ascidian Aplidium fuegiense resulted in the isolation of three novel meroterpenoids 2–4, structurally related to the main co-occurring known rossinone B (1). The structures of the new compounds were determined by interpretation of spectroscopic data. Compounds 1–4 were found to be selectively localized in the viscera of the ascidian.

The use of mechanical trading systems allows managing a huge amount of data related to the factors affecting investment performance (macroeconomic variables, company information, industrial indicators, market variables, etc.) while avoiding the psychological reactions of traders when they invest in financial markets. When trading is executed in an intra-daily frequency instead a daily frequency, mechanical trading systems needs to be supported by very powerful engines since the amount of data to deal with grow while the response time required to support trades gets shorter. Numerous studies document the use of genetic algorithms (GAs) as the engine driving mechanical trading systems. The empirical insights provided in this paper demonstrate that the combine use of GA together with a GPU-CPU architecture speeds up enormously the power and search capacity of the GA for this kind of financial applications. Moreover, the parallelization allows us to implement and test previous GA approximations. Regarding the investment results, we can report 870% of profit for the S&P 500 companies in a 10-year time period (1996–2006), when the average profit of the S&P 500 in the same period was 273%.

Predation and competition are important factors structuring Antarctic benthic communities and are expected to promote the production of chemical defenses. Tunicates are subject to little predation, and this is often attributed to chemical compounds, although their defensive activity has been poorly demonstrated against sympatric predators. In fact, these animals, particularly the genus Aplidium, are rich sources of bioactive metabolites. In this study, we report the natural products, distribution and ecological activity of two Aplidium ascidian species from the Weddell Sea (Antarctica). In our investigation, organic extracts obtained from external and internal tissues of specimens of A. falklandicum demonstrated to contain deterrent agents that caused repellency against the Antarctic omnivorous predator, the sea star Odontaster validus. Chemical analysis performed with Antarctic colonial ascidians Aplidium meridianum and Aplidium falklandicum allowed the purification of a group of known bioactive indole alkaloids, meridianins A-G. These isolated compounds proved to be responsible for the deterrent activity. Funding was provided by the Ministry of Science and Education of Spain through the ECOQUIM Projects (REN2003-00545, REN2002-12006E ANT and CGL2004-03356/ANT).

A detailed geochemical study was conducted at the inactive Zn–Pb mine of Santa Lucia, in western Cuba. The studied mine-wastes are characterized by high total concentrations of potentially toxic elements (PTE), with average values of 17.4% Fe, 5.47% Ba, 2.27% Pb, 0.83% Zn, 1724 mg/kg As and 811 mg/kg Cu. Oxidation of sulfide minerals in mine-waste dumps and in the open pit produces acid mine effluents (pH = 2.5–2.6) enriched in dissolved SO 4 2 - (up to 6754 mg/L), Fe (up to 4620 mg/L) and Zn (up to 2090 mg/L). Low pH values (2.5–2.8) and high dissolved concentrations of the same PTE were found in surface waters, up to 1500 m downstream from the mine. Nevertheless, concentrations of As, Ba and Pb in acid mine effluents and impacted surface waters are relatively low: 0.01–0.3 mg/L As, 0.002–0.03 mg/L Ba and 0.3–4.3 mg/L Pb. Analysis by X-ray diffraction and electron microscopy revealed the occurrence of lead–bearing barite and beudantite and the more common solid phases, reported elsewhere in similar environments including Fe-oxyhydroxides, jarosite, anglesite and plumbojarosite. Because the reported solubilities for barite and beudantite are very low under acidic conditions, these minerals may serve as the most important control in the mobility of As, Ba and Pb. In contrast, Fe-oxyhydroxides are relatively soluble under acidic conditions and, therefore, they may have a less significant role in PTE on-site immobilization. Mine-wastes and stream sediments show a light REE (LREE) and middle REE (MREE) enrichment relative to heavy REE (HREE). In contrast, acid mine effluents and surface waters are enriched in HREE relative to LREE. These results suggest that the LREE released during the oxidation of sulfides are captured by secondary (weathering) minerals, while the MREE are removed from the altered rocks. The low concentrations of LREE in acid stream water suggest that these elements can be retained in the sediments more strongly than HREE and MREE. One possible explanation for the sharp decrease in dissolved LREE might be their retention by low-solubility secondary minerals such as anglesite, barite and jarosite.

Resumen Introduccion La investigacion de los mecanismos de enfermedad del asma y la identificacion de nuevas dianas terapeuticas requieren modelos animales experimentales. En este trabajo presentamos los datos del desarrollo de un modelo murino de asma experimental que permite valorar de forma conjunta parametros de inflamacion y remodelacion de las vias respiratorias mediante morfologia cuantitativa. Material y metodos Se sensibilizo a ovoalbumina a ratones Balb/c y se les realizo broncoprovocacion con ovoalbumina o excipiente 3 veces por semana durante 12 semanas. Resultados En el lavado broncoalveolar, los ratones del grupo de ovoalbumina presentaron un incremento significativo de leucocitos totales, con una mediana (cuartiles 25–75) de 670,0 celulas/ml·103 (376,2–952,5), frente a 40,0 celulas/ml·103 (60,0–85,0) en controles (p=0,001), y de las fracciones eosinofila y linfocitaria en recuento diferencial. En secciones sagitales de los pulmones inflados a presion estandarizada, estos ratones mostraron hiperplasia de celulas caliciformes en el epitelio respiratorio —reaccion de acido peryodico de Schiff: 53,89 (36,26–62,84) frente a 0,66 (0,00–1,06) celulas/mm2 (p Conclusiones Los datos aportados configuran un modelo de asma experimental inducida por exposicion alergenica prolongada, con desarrollo y evaluacion integrada de inflamacion y remodelacion de vias respiratorias.

Chemical investigation of the lipophilic extract of the Antarctic soft coral Alcyonium grandis led us to the finding of nine unreported sesquiterpenoids, 2-10. These molecules are members of the illudalane class and in particular belong to the group of alcyopterosins, illudalanes isolated from marine organisms. The structures of 2-10 were determined by interpretation of spectroscopic data. Repellency experiments conducted using the omnivorous Antarctic sea star Odontaster validus revealed a strong activity in the lipophilic extract of A. grandis against predation.

Fundamento y objetivo El objetivo de este estudio es cuantificar la eficacia del tratamiento cognitivo-conductual para la deshabituacion tabaquica en el embarazo y objetivar los factores de riesgo de exito o fracaso para la abstinencia antes del parto. Pacientes y metodo Se estudio a 74 mujeres embarazadas y fumadoras que entre enero de 2003 y enero de 2004 acudieron a su visita de control obstetrico regular en el Hospital Casa Maternitat-Hospital Clinic i Provincial de Barcelona, y que voluntariamente accedieron al tratamiento cognitivo-conductual sin sustitucion de nicotina para la deshabituacion tabaquica que se les ofrecio. Resultados El 44% de las mujeres que realizaron el programa de visitas llego abstinente al parto, y de ellas el 93,1% se mantuvo abstinente durante la cuarentena. El 51,5% redujo el consumo y un 4,5% se mantuvo sin cambios o aumento el consumo. El hecho de que alguien fume en casa (p = 0,006), el grado de dependencia de la nicotina (p = 0,015) y un consumo de cafe superior a 3 tazas/dia (p = 0,039), en una ecuacion de regresion logistica, separaron los 2 grupos (abstinencia/no abstinencia). Conclusiones La eficacia de un programa basado en el tratamiento cognitivo-conductual, sin sustitucion de nicotina, para la deshabituacion tabaquica en el embarazo se ha confirmado en nuestra muestra. Se propone contemplar como factores de riesgo de fracaso en el tratamiento el hecho de que alguien fume en casa y un consumo elevado de cafe.

The function of KlSRB10 has been studied by diverse approaches. Primer extension analysis reveals several transcription start sites, position - 17 from ATG being predominant. Deletion of KlSRB10 diminishes growth in ethanol and decreases KlCYC1 transcript levels. A second phenotype associated with this deletion affects growth in galactose. These phenotypes are independent of the specific sequence connecting the ATP binding cassette and the kinase domain of Srb10p in yeasts. KlSrb10p is not necessary for LAC4 repression mediated by KlGal80p, as deduced by construction of a Klgal80Deltasrb10Delta double mutant. In the two-hybrid system, KlSrbp10p interacts with the protein encoded by KLLA0E08151g (KlSrbp11p).

La respuesta inflamatoria frente a toxicos del humo del tabaco es crucial en los mecanismos patogenicos de la enfermedad pulmonar obstructiva cronica (EPOC). Las celulas inflamatorias tradicionalmente consideradas clave son los macrofagos y los neutrofilos, debido a su presencia aumentada en fumadores y sujetos con EPOC, y a su capacidad para secretar diversas proteasas con capacidad para degradar componentes de la matriz extracelular, ademas de las quimiocinas y las citocinas, que amplifican la inflamacion, y los radicales oxidantes. Los oxidantes presentes en el humo del tabaco, mas los producidos por la actividad inflamatoria, desbordan la capacidad de los mecanismos fisiologicos de proteccion antioxidante e inducen estres oxidativo, que puede producir dano directo en las celulas estructurales, amplificar la inflamacion y favorecer la degradacion proteolitica de los tejidos, al inhibir los sistemas antiproteasa. Adicionalmente, el estres oxidativo puede alterar la regulacion de la expresion genetica e interferir con los sistemas de remodelacion de cromatina. Como consecuencia, se activa la transcripcion de genes de accion inflamatoria y se bloquea un mecanismo critico de accion de la medicacion esteroidea. Una teoria propuesta recientemente es la existencia en la EPOC de una respuesta autoinmunitaria contra antigenos liberados por dano celular, o formados por modificacion quimica de proteinas. Los efectores serian celulas T CD4+ con activacion Th1, y celulas T CD8+ citotoxicas que inducirian apoptosis de celulas estructurales. Como consecuencia de esta diversidad de mecanismos, se produce remodelacion estructural en las vias respiratorias centrales y perifericas, el parenquima y los vasos pulmonares, y se generan las manifestaciones clinicas de la enfermedad.

Leire Lodeiro-Fernández, Laura Lorenzo-López, Ana Maseda, Laura Núñez-Naveira, José Luis Rodríguez-Villamil, José Carlos Millán-Calenti Gerontology Research Group, Department of Medicine, Faculty of Health Sciences, University of A Coruña, Campus of A Coruña, ACoruña, Spain Purpose: The possible relationship between audiometric hearing thresholds and cognitive performance on language tests was analyzed in a cross-sectional cohort of older adults aged ≥65 years (N=98) with different degrees of cognitive impairment.Materials and methods: Participants were distributed into two groups according to Reisberg’s Global Deterioration Scale (GDS): a normal/predementia group (GDS scores 1–3) and a moderate/moderately severe dementia group (GDS scores 4 and 5). Hearing loss (pure-tone audiometry) and receptive and production-based language function (Verbal Fluency Test, Boston Naming Test, and Token Test) were assessed.Results: Results showed that the dementia group achieved significantly lower scores than the predementia group in all language tests. A moderate negative correlation between hearing loss and verbal comprehension (r=-0.298; P

Out of the many bioactive compounds described from the oceans, only a small fraction have been studied for their ecological significance. Similarly, most chemically mediated interactions are not well understood, because the molecules involved remain unrevealed. In Antarctica, this gap in knowledge is even more acute in comparison to tropical or temperate regions, even though polar organisms are also prolific producers of chemical defenses, and pharmacologically relevant products are being reported from the Southern Ocean. The extreme and unique marine environments surrounding Antarctica along with the numerous unusual interactions taking place in benthic communities are expected to select for novel functional secondary metabolites. There is an urgent need to comprehend the evolutionary role of marine derived substances in general, and particularly at the Poles, since molecules of keystone significance are vital in species survival, and therefore, in structuring the communities. Here we provide a mini-review on the identified marine natural products proven to have an ecological function in Antarctic ecosystems. This report recapitulates some of the bibliography from original Antarctic reviews, and updates the new literature in the field from 2009 to the present.

[Abstract] Objective. The prevalence of dementia is increasing and consequently the demands from families, institutions and healthcare system. Although a substantial amount of research on caregiving has emphasized the negative aspects of caregiving, specifically on caregiver burden and depression, less attention has been paid to the positive aspects of caregiving. The aim of the present work was to study the phenomenon of caregiving satisfaction in informal caregivers of people with dementia by assessing their likely predictors. Methods. A stress process model was used to study caregiver's satisfaction (measured using the Revised Caregiving Satisfaction Scale) on 101 informal caregivers of patients with dementia in relation to the caregiver's background and context, stress-related factors, and mediators. Results. The regression model has an adjusted R2 of 0.20, which indicates that having a consanguinity relationship with the care recipient, suffering from lower levels of subjective burden, and managing individuals with severe cognitive impairment are the most important predictors of higher caregiving satisfaction. Conclusion. Interventions focused on the enhancement of the caregiving satisfaction by increasing the understanding of the disease, should be especially addressed to caregivers without a consanguinity relationship and with high levels of subjective burden, and to those managing care recipients with mild or moderate stages of dementia. Ministerio de Industria, Energía y Turismo; AAL-2012-5-107

Con frecuencia, el diseño de actividades dinámicas y atractivas para la enseñanza de las matemáticas es uno de los principales retos a los que se enfrentan los profesores de dicha materia, debido a que el Programa de Estu-dios 2011 del Sistema Educativo Mexicano considera que es el docente quien debe propiciar situaciones didácticas para despertar el interés en los alumnos; promoviendo el desarrollo de ciertas habilidades, tanto a través del trabajo individual y autónomo como colectivo. Buscando diseñar y validar experiencias que favorezcan el proceso de enseñan-za-aprendizaje de las matemáticas, se llevó a cabo la presente investigación, la cual tuvo como objetivo evaluar el impacto del taller “Juguemos con Álgebra” en la conceptualización de la materia de matemáticas en alumnos de 3° grupo A de la escuela secundaria Alberto Larios Villalpando, turno vespertino, así como también el impacto en el rendimiento académico en el tema de expresiones algebraicas y resolución de ecuaciones lineales. En dicho taller se puso en práctica lo propuesto en el Programa de Estudios 2011, es decir, trabajar con base en un enfoque didáctico, el cual consiste en problematizar a los alumnos para que discutan y analicen sus procedimientos y resultados, apoyando esto con el juego, como recurso para la enseñanza del álgebra.

Outlines the development of genetic algorithms (GA), explains how they generate solutions to problems and applies four GA models incorporating different factors (e.g. risk, transaction costs etc.) to financial investment strategies. Uses 1987‐1996 share price data from the Madrid Stock Exchange (Spain) and a buy‐and‐hold strategy in the IBEX‐35 index as a benchmark. Shows that all four GA models generat superior daily returns of long positions with lower risk; and discusses the variations between them in detail.

Taking into account the broad biological activities found in the meridianin indole alkaloids isolated to date, we have re-examined the organic extracts of an Antarctic collection of the tunicates Aplidium meridianum and A. falklandicum (Chordata: Ascidiacea) by HPLC in conjunction with a high-resolution mass spectrometer (HPLC-MS). A new set of analogs of meridianins A-G has been detected, and their structures are proposed on the basis of the molecular formulae identified by LC-HRMS analysis using a C18 column with a gradient of water/acetonitrile and an LTQ-FT-MS Orbitrap detector. Remarkably, dimers derived from meridianin A and from meridianin B or E were also detected. Our findings provide further evidence of the broad variability within the meridianin-like derivatives of this highly bioactive alkaloid family.

[Abstract] Objectives: To establish the possible relationship among three components of language (verbal fluency, naming and comprehension) and cognitive impairment as well as to determine the usefulness of language assessment tests to predict or monitor the development of cognitive impairment. Method: A comparative, descriptive and cross-sectional study was performed on 82 subjects 65 years of age who were cognitively assessed with the Mini Mental State Examination and were divided into two groups: Group A comprised of subjects classified as levels 1, 2 and 3 on the Reisberg’s Global Deterioration Scale (GDS) and group B comprised of subjects at levels 4 and 5 of the GDS. Language skills were assessed by the Verbal Fluency Test, Boston Naming Test and Token Test. Results: An inverse relationship between performance on language tests and cognitive impairment level was observed with a more pronounced effect observed on fluency and comprehension tests. Conclusion: Language assessments, especially fluency and comprehension, were good indicators of cognitive impairment. The use of these assessments as predictors of the degree of cognitive impairment is discussed in-depth.

Glycation and nitrotyrosination are pathological posttranslational modifications that make proteins prone to losing their physiological properties. Since both modifications are increased in Alzheimer's disease (AD) due to amyloid-β peptide (Aβ) accumulation, we have studied their effect on albumin, the most abundant protein in cerebrospinal fluid and blood. Brain and plasmatic levels of glycated and nitrated albumin were significantly higher in AD patients than in controls. In vitro turbidometry and electron microscopy analyses demonstrated that glycation and nitrotyrosination promote changes in albumin structure and biochemical properties. Glycated albumin was more resistant to proteolysis and less uptake by hepatoma cells occurred. Glycated albumin also reduced the osmolarity expected for a solution containing native albumin. Both glycation and nitrotyrosination turned albumin cytotoxic in a cell type-dependent manner for cerebral and vascular cells. Finally, of particular relevance to AD, these modified albumins were significantly less effective in avoiding Aβ aggregation than native albumin. In summary, nitrotyrosination and especially glycation alter albumin structural and biochemical properties, and these modifications might contribute for the progression of AD. This work was supported by the Spanish Ministry of Science and Innovation (SAF2012-38140; BIO2011-25039); Fondo de Investigación Sanitaria (PI10/00587; PI11/3035; and Red HERACLES RD06/0009, RD12/0042/0014); FEDER Funds; Generalitat de Catalunya (SGR05-266; SGR09-760); and Fundació la Marató de TV3 (100310). M.A.V. is the recipient of an ICREA Academia Award.

Xavier, José C. et al., Polar marine ecosystems have global ecological and economic importance because of their unique biodiversity and their major role in climate processes and commercial fisheries, among others. Portugal and Spain have been highly active in a wide range of disciplines in marine biology of the Antarctic and the Arctic. The main aim of this paper is to provide a synopsis of some of the results and initiatives undertaken by Portuguese and Spanish polar teams within the field of marine sciences, particularly on benthic and pelagic biodiversity (species diversity and abundance, including microbial, molecular, physiological and chemical mechanisms in polar organisms), conservation and ecology of top predators (particularly penguins, albatrosses and seals), and pollutants and evolution of marine organisms associated with major issues such as climate change, ocean acidification and UV radiation effects. Both countries have focused their polar research more in the Antarctic than in the Arctic. Portugal and Spain should encourage research groups to continue increasing their collaborations with other countries and develop multi-disciplinary research projects, as well as to maintain highly active memberships within major organizations, such as the Scientific Committee for Antarctic Research (SCAR), the International Arctic Science Council (IASC) and the Association of Polar Early Career Scientists (APECS), and in international research projects. © 2013 Elsevier B.V.

The Antarctic sea star Odontaster validus and the amphipod Cheirimedon femoratus are important predators in benthic communities. Some bryozoans are part of the diet of the asteroid and represent both potential host biosubstrata and prey for this omnivorous lysianassid amphipod. In response to such ecological pressure, bryozoans are expected to develop strategies to deter potential predators, ranging from physical to chemical mechanisms. However, the chemical ecology of Antarctic bryozoans has been scarcely studied. In this study we evaluated the presence of defenses against predation in selected species of Antarctic bryozoans. The sympatric omnivorous consumers O. validus and C. femoratus were selected to perform feeding assays with 16 ether extracts (EE) and 16 butanol extracts (BE) obtained from 16 samples that belonged to 13 different bryozoan species. Most species (9) were active (12 EE and 1 BE) in sea star bioassays. Only 1 BE displayed repellence, indicating that repellents against the sea star are mainly lipophilic. Repellence toward C. femoratus was found in all species in different extracts (10 EE and 12 BE), suggesting that defenses against the amphipod might be both lipophilic and hydrophilic. Interspecific and intraspecific variability of bioactivity was occasionally detected, suggesting possible environmental inductive responses, symbiotic associations, and/or genetic variability. Multivariate analysis revealed similarities among species in relation to bioactivities of EE and/or BE. These findings support the hypothesis that, while in some cases alternative chemical or physical mechanisms may also provide protection, repellent compounds play an important role in Antarctic bryozoans as defenses against predators.

Trading Systems are beneficial for financial investments due to the complexity of nowadays markets. On one hand, finance markets are influenced by a great amount of factors of different sources such as government policies, natural disasters, international trade, political factors etc. On the other hand, traders, brokers or practitioners in general could be affected by human emotions, so their behaviour in the stock market becomes nonobjective. The high pressure induced by handling a large volume of money is the main reason of the so-called market psychology. Trading systems are able to avoid a great amount of these factors, allowing investors to abstract the complex flow of information and the emotions related to the investments. In this paper we compare two trading systems based on Evolutionary Computation. The first is a GA-based one and was already proposed and tested with data from 2006. The second one is a grammatical evolution approach which uses a new evaluation method. Experimental results show that the later outperforms the GA approach with a set of selected companies of the spanish market with 2012 data.

[Abstract] Background/aims It has been shown that cognitive training might help to protect against age-related cognitive decline. Our aim was to evaluate the efficacy of a computerized cognitive training application and its near transfer effects on the cognitive status of older adults. Methods Performance on the 7-Minute Screen at baseline and at the end of the program was analyzed by using a prepost design. Adults aged 55 and older (n = 101; mean age ± standard deviation: 68.97 ± 5.81 years) with and without memory impairments were trained. Results Significant improvements after the training program were found in memory, visuo-spatial and verbal fluency abilities, regardless of age, gender or education. Moreover, participants without significant memory impairments and those with Age-Associated Memory Impairment gained from the program more than subjects with mild cognitive impairment. Conclusion Computerized cognitive training programs, such as Telecognitio , may be used as a practical and valuable tool in clinic to improve cognitive status.

El trabajo que presentamos a continuación es una parte de un trabajo más complejo que se realizó en la zona de Taxco en México y Santa Lucía y Matahambre en el noroeste de Pinar del Río, Cuba. En este caso se exponen los resultados del estudio detallado de las áreas aledañas a la mina subterránea inactiva cuprífera Matahambre, en la parte más occidental de la actual provincia de Pinar del Río, Cuba. Se estudiaron los residuos acumulados en la presa de cola y las áreas aledañas a la mina. Se tomaron muestras liquidas a lo largo del arroyo que drena desde dicha presa de cola y hasta una distancia de 200 metros, se pudo observar que ya a los 15 metros de distancia el drenaje dejaba de ser ácido. A partir de aquí se obtuvieron valores de pH de alrededor de 7.53. Posteriormente se compararon los resultados obtenidos en la mina inactiva a cielo abierto Santa Lucía y Taxco. Se pudo concluir que en el yacimiento Matahambre no existe afectación al medio ambiente. Esto es debido a las condiciones en que se encuentra la presa de cola y la atenuación natural del cobre y demás Elementos Potencialmente Tóxicos (EPT). La utilización de dicha presa como un sitio de cultivo de hortalizas y vegetales, luego de aislarla con una capa de arena y capa vegetal con turba, ayuda considerablemente a aislar los depósitos que contienen minerales residuos del proceso de beneficio del yacimiento Matahambre, para evitar la aparición de drenaje ácido de mina. Esto podría ser una solución para otros sitios mineros donde la presa de cola o jales se encuentran a la intemperie y generan gran cantidad de drenaje ácido de mina.

Ascidians have developed multiple defensive strategies mostly related to physical, nutritional or chemical properties of the tunic. One of such is chemical defense based on secondary metabolites. We analyzed a series of colonial Antarctic ascidians from deep-water collections belonging to the genera Aplidium and Synoicum to evaluate the incidence of organic deterrents and their variability. The ether fractions from 15 samples including specimens of the species A. falklandicum, A. fuegiense, A. meridianum, A. millari and S. adareanum were subjected to feeding assays towards two relevant sympatric predators: the starfish Odontaster validus, and the amphipod Cheirimedon femoratus. All samples revealed repellency. Nonetheless, some colonies concentrated defensive chemicals in internal body-regions rather than in the tunic. Four ascidian-derived meroterpenoids, rossinones B and the three derivatives 2,3-epoxy-rossinone B, 3-epi-rossinone B, 5,6-epoxy-rossinone B, and the indole alkaloids meridianins A–G, along with other minoritary meridianin compounds were isolated from several samples. Some purified metabolites were tested in feeding assays exhibiting potent unpalatabilities, thus revealing their role in predation avoidance. Ascidian extracts and purified compound-fractions were further assessed in antibacterial tests against a marine Antarctic bacterium. Only the meridianins showed inhibition activity, demonstrating a multifunctional defensive role. According to their occurrence in nature and within our colonial specimens, the possible origin of both types of metabolites is discussed.

Antarctic marine ecosystems are immersed in an isolated, relatively constant environment where the organisms inhabiting their benthos are mainly sessile suspension feeders. For these reasons, physical and chemical biotic interactions play an essential role in structuring these marine benthic communities (Dayton et al., 1974; Orejas et al., 2000). These interactions may include diverse strategies to avoid predation (e.g. Iken et al., 2002), competition for space or food (e.g. Bowden et al., 2006) and avoiding fouling (e.g. Rittschof, 2001; Peters et al., 2010). For instance, in the marine benthos, one of the most extended effective strategies among sessile soft-bodied organisms is chemical defense, mediated by several bioactive natural products mostly considered secondary metabolites (e.g. Paul et al., 2011). The study of the “chemical network” (chemical ecology interactions) structuring the communities provides information about the ecology and biology of the involved species, the function and the structure of the community and, simultaneously, it may lead to the discovery of new compounds useful to humans for their pharmacological potential (e.g. Avila, 1995; Bhakuni, 1998; Munro et al., 1999; Faulkner, 2000; Lebar et al., 2007; Avila et al., 2008). In the last three decades, the study of marine chemical ecology has experienced great progress, thanks to the new technological advances for collecting and studying marine samples, and the possibility of identification of molecules with smaller amounts of compounds (e.g. Paul et al., 2006, 2011; Blunt et al., 2011).

Hexactinellids (glass sponges) are an understudied class with syncytial organization and poor procariotic associations, thought to lack defensive secondary metabolites. Poriferans, though, are outstanding sources of bioactive compounds; nonetheless, a growing suspicion suggests that many of these chemicals could be symbiont-derived. In Polar latitudes, sponges are readily invaded by diatoms, which could provide natural products. Hexactinellids are typical of deep waters; but in Antarctica, they dominate the upper shelf providing shelter and food supply to many opportunistic mesograzers and macroinvertebrates, which exert strong ecological pressures on them. Aiming to examine the incidence of defensive activities of hexactinellids against consumption, feeding experiments were conducted using their lipophilic fractions. Antarctic hexactinellid and demosponge extracts were tested against the asteroid Odontaster validus and the amphipod Cheirimedon femoratus as putative sympatric, omnivorous consumers. Hexactinellids yielded greater unpalatable activities towards the amphipod, while no apparent allocation of lipophilic defenses was noted. After chemical analyses on the lipophilic fractions from these Antarctic glass sponges, quite similar profiles were revealed, and no peculiar secondary metabolites, comparable to those characterizing other poriferans, were found. Instead, the lipidic compounds 5α(H)-cholestan-3-one and two glycoceramides were isolated for their particular outspread presence in our samples. The isolated compounds were further assessed in asteroid feeding assays, and their occurrence was evaluated for chemotaxonomical purposes in all the Antarctic samples as well as in glass sponges from other latitudes by NMR and MS. Characteristic sphingolipids are proposed as chemical markers in Hexactinellida, with possible contributions to the classification of this unsettled class.

Exhaled breath condensate (EBC) is a representative sample from the lungs that may be used to detect different markers, but the reproducibility of these determinations is unknown over time. The aim of this paper is to assess the reproducibility of protein marker determination in EBC using samples collected at two different time points. EBC and blood were collected from 16 healthy subjects, smokers and non-smokers by using the ECoScreen device. EBC was collected on two separate occasions within ten days. Enzyme-linked immunosorbent assay (ELISA) was performed to measure angiogenesis and hypoxia markers. Blood and EBC samples were analyzed by ELISA to detect angiogenesis markers: vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and endostatin. A hypoxia marker, the anhydrase IX, was also determined. Biomarker concentration was higher in plasma samples compared to EBC. bFGF determination was higher in women (39.47 ± 3.914 versus 27.15 ± 3.145; p < 0.05). There were no significant differences among the averages of detection for any of the markers. The Bland-Altman method showed that the average of the differences or biases in EBC for every biomarker was close to zero, indicating a good reproducibility of the measurements. Nevertheless, the VEGF showed wide limits of agreement. EBC is suitable to detect biomarkers by ELISA and the measurements are reproducible over time. Nevertheless, some factors such as sex should be taken into account when analyzing the results.

Although financial literature presents ambiguous evidence about the predicting value of fundamental and technical variables in stock markets, we find that evolving trading models based on fundamental variables substantially reduce the risk of investing in stocks. This reduction is so generous that the risk-adjusted return obtained following these fundamental variables to trade individual stocks is superior to that obtained by the passive investing in the same individual stocks. However the technical indicators we analyze do not show any predicting value neither in terms of return or risk. We observe the dynamics of individual stock prices’ return and risk in a new framework, the Adaptive Market Hypothesis (AMH) proposed recently by Lo (2004). Using this framework, we examine if there is room to improve investment strategies when adapting them to the potential changing conditions of financial markets or to the investors’ learning process. This adaptation is carried out by quantitative adaptive models driven by evolutionary algorithms (genetic algorithms) that update, over time, the threshold values for fundamental and technical indicators. We find that adaptation improves the risk-adjusted return of investment strategies. We test our trading models using a large sample of companies: non-financial firms with data available in Compustat database which have been listed in the S&P 500 for at least two quarters during the period 1976 - 2006. Our sample consists of 332,700 firm-quarterly observations for fundamental trading systems and 7,157,320 firm-daily observations for technical trading systems. Our models are run using parallel computation executed on 81 computers with a global capacity of 225 GFLOPS or (225x109) FLOPS (floating point operations per second) at the Computational Laboratory of the IT School of Madrid’s Complutense University.

Nowadays, there are two types of financial analysis oriented to design trading systems: fundamental and technical. Fundamental analysis consists in the study of all information (both financial and nonfinancial) available on the market, with the aim of carrying out efficient investments. By contrast, technical analysis works under the assumption that when we analyze the price action in a specific market, we are (indirectly) analyzing all the factors related to the market. In this paper we propose the use of an Evolutionary Algorithm to optimize the parameters of a trading system which combines Fundamental and Technical analysis (indicators). The algorithm takes advantage of a new operator called Filling Operator which avoids problems of premature convergence and reduce the number of evaluations needed. The experimental results are promising, since when the methodology is applied to values of 100 companies in a year, they show a possible return of 830% compared with a 180% of the Buy and Hold strategy.