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Evidence shows that patients affected by Parkinson’s disease (PD) display the tendency toward making risky choices. This is due, at least in part, to the pathophysiological characteristics of the disease that affects neural areas underlying decision making (DM), in which a pivotal role is played by nonmotor corticostriatal circuits and dopamine. Executive functions (EFs), which can be impaired by PD as well, may sustain optimal choices in DM processes. However, few studies have investigated whether EFs can support PD patients to make good decisions. Adopting the scoping review approach, the present article is designed to deepen the cognitive mechanisms of DM under conditions of ambiguity and risk (that are conditions common to everyday life decisions) in PD patients without impulse control disorders. We focused our attention on the Iowa Gambling Task and the Game of Dice Task, because they are the most commonly used and reliable tasks to assess DM under ambiguity and under risk, respectively, and analyzed the performances in such tasks and their relationships with EFs tests in PD patients. The analysis supported the relationships between EFs and DM performance, especially when a higher cognitive load is required to make optimal decisions, as it happens under conditions of risk. Possible knowledge gaps and further research directions are suggested to better understand DM mechanisms in PD sustaining patients’ cognitive functioning and preventing negative consequences in everyday life derived from suboptimal decisions.

The Matanza Riachuelo Basin is one of the most polluted watersheds in the world. We assessed the relationships between land use, stream-water quality, and the structure of the fish assemblages on a subbasin scale from data obtained in 44 sampling sites. A gradient of change from the rural upper sector to the urbanized and industrialized lower basin in conjunction with water-quality impoverishment was recorded. Redundancy analysis revealed that dissolved oxygen concentration, heavy metals, detergents, and Escherichia coli were the most explanatory variables of that gradient. Fish assemblages manifested the highest richness, abundance, and diversity in the rural areas; in the urbanized and industrialized sectors, the fish community became severely modified, represented only by tolerant species. Multivariate analyses indicated that the fish assemblage structure was highly impacted by water-quality deterioration. The combined study of the impacts of land use on water quality and fish assemblages enabled a detailed diagnosis of the consequent effects on a subbasin scale, thus substantiating the usefulness of fish assemblages as a model for that purpose. Field studies over large-scale gradients of environmental impact are essential for understanding the mechanisms of ecological deterioration and biotic responses as a first step in developing remediation policies.

Single-photon sources have a variety of applications. One of these is quantum radiometry, which is reported on in this paper in the form of an overview, specifically of the current state of the art in the application of deterministic single photon sources to the calibration of single photon detectors. To optimize single-photon sources for this purpose, extensive research is currently carried out at the European National Metrology Institutes (NMIs), in collaboration with partners from universities. Single-photon sources of different types are currently under investigation, including sources based on defect centres in (nano-)diamonds, on molecules and on semiconductor quantum dots. We will present, summarise, and compare the current results obtained at European NMIs for single-photon sources in terms of photon flux, single-photon purity, and spectral power distribution as well as the results of single-photon detector calibrations carried out with this type of light sources.

The emergence and rapid global spread of SARS-CoV-2 demonstrates the importance of infectious disease surveillance, particularly during the early stages. Viral genomes can provide key insights into transmission chains and pathogenicity. Nasopharyngeal swabs were obtained from thirty-two of the first SARS-CoV-2 positive cases (March 18–30) in Kingston Ontario, Canada. Viral genomes were sequenced using Ion Torrent (n = 24) and MinION (n = 27) sequencing platforms. SARS-CoV-2 genomes carried forty-six polymorphic sites including two missense and three synonymous variants in the spike protein gene. The D614G point mutation was the predominate viral strain in our cohort (92.6%). A heterozygous variant (C9994A) was detected by both sequencing platforms but filtered by the ARTIC network bioinformatic pipeline suggesting that heterozygous variants may be underreported in the SARS-CoV-2 literature. Phylogenetic analysis with 87,738 genomes in the GISAID database identified global origins and transmission events including multiple, international introductions as well as community spread. Reported travel history validated viral introduction and transmission inferred by phylogenetic analysis. Molecular epidemiology and evolutionary phylogenetics may complement contact tracing and help reconstruct transmission chains of emerging diseases. Earlier detection and screening in this way could improve the effectiveness of regional public health interventions to limit future pandemics.

The aim of this study was to analyze the temporal long term variability of fish assemblage in Chascomús Lake. Data acquisition was based on documented historical research fishing records and experimental fishing program performed from 1999 to 2013. Fish assemblage composition showed a strong temporal variability. Planktivorous species such as Platanichthys platana, Odontesthes bonariensis and Parapimelodus valenciennis accounted for the 70 to 80% of relative abundance becoming alternatively dominant. The iliophagous Cyphocharax voga, the forth dominant species, shared with P. valenciennis the pattern of change in their relative abundance along time. O. bonariensis and P. platana showed high fluctuations in their representation from dominant to almost disappearance during the considered period. Cluster analysis allowed the identification of four different groups of fish assemblage configuration. Two of them grouped the data from historical studies meanwhile the other encompasses the samples taken between 1999-2012, being the discriminant species the mentioned above. Water level, critical temperatures and man basin modifications are discussed as main drivers of species relative abundance shifts. The study highlights the importance to build a long-term assessments to understand how fish assemblage modifications are linked to the typical pampean floods and drought cycles coupled with unfavorable thermal conditions and water management impacts. Fil: Colautti, Dario César. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Instituto de Limnología "dr. Raul A. Ringuelet". Universidad Nacional de la Plata. Facultad de Cs.naturales y Museo. Instituto de Limnología "dr. Raul A. Ringuelet"; Argentina Fil: Baigún, Claudio Rafael M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "dr. Raul Alfonsin" (sede Chascomus) | Universidad Nacional de San Martin. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "dr. Raul Alfonsin" (sede Chascomus); Argentina Fil: Llompart, Facundo Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Maiztegui, Tomás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Instituto de Limnología "dr. Raul A. Ringuelet". Universidad Nacional de la Plata. Facultad de Cs.naturales y Museo. Instituto de Limnología "dr. Raul A. Ringuelet"; Argentina Fil: Garcia, Javier Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Instituto de Limnología "dr. Raul A. Ringuelet". Universidad Nacional de la Plata. Facultad de Cs.naturales y Museo. Instituto de Limnología "dr. Raul A. Ringuelet"; Argentina Fil: Solimano, Patricio José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Instituto de Limnología "dr. Raul A. Ringuelet". Universidad Nacional de la Plata. Facultad de Cs.naturales y Museo. Instituto de Limnología ; Argentina Fil: Balboni, Leandro. Ministerio de Agricultura, Ganaderia, Pesca y Alimento; Argentina Fil: Berasain, G.. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios; Argentina

Odontesthes bonariensis is an inland water fish from the Pampas region, valued due to the quality of its flesh and its attractiveness as a game fish. Chasico´ Lake located in the south of the pampean region is appreciated by fishermen due to O. bonariensis abundance. However, in the last year, a reduction in their catches was recorded. In this work, it was analyzed the changes of O. bonariensis biomass in relation to climate change and salinity in Chasico´ Lake from 1997 to 2013. From 2004 to 2013, when a dry period began, a reduction in lake area (68.1?47.4 km2) and an increase in salinity (18.9?41.5 g l-1) were observed. O. bonariensis catches showed a significant decrease in the same period as a result of salinity increments. Possibly, at high salinity, O. bonariensis may still develop but with an impaired reproduction and limited embryo and juvenile survival. In conclusion, after 2004, the fishery quality in Chasico´ Lake showed a decreasing trend from the maximum registered in the Pampas lakes. This was in agreement with a marked decrease in the lake area which in turn increased water salinity up to levels close to the O. bonariensis tolerance limit. Fil: Berasain, Gustavo Emilio. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios; Argentina Fil: Colautti, Dario César. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentina Fil: Remes Lenicov, Federico. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Argemi, Federico. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios; Argentina Fil: Bohn, Vanesa Yael. Universidad Nacional del Sur. Departamento de Geografía y Turismo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Miranda, Leandro Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina

Invasions biologists have frequently debated whether the definition of invasive should include ecological and economic impacts. More recent criticisms posit that objective definitions are impossible in any absolute sense, while subjectivity is desirable for its flexibility and motivational qualities. We argue that such criticisms underestimate the extent of subjectivity already present in invasion biology. Ecological questions may be methodological if they relate directly to other ecological theories and models, or motivational if they focus on issues important to society as a whole. Motivational questions are important for engaging scientists, improving public understanding of science, and often have applied benefits. In contrast, methodological questions are constrained by established scientific theories, and are therefore more efficient for the development of scientific knowledge. Contrary to recent critiques, we suggest that greater objectivity is both achievable and desirable for the discipline of invasion biology and ecology generally.

A fully-integrated surface-subsurface flow and transport model is applied to a 17 km2 subcatchment of the Laurel Creek Watershed within the Grand River basin in Southern Ontario, Canada. Through past and ongoing field studies, the subcatchment is reasonably well characterized and is being monitored on an ongoing basis. In addition to diverse land-usage and surface cover and more than 65 m of topographic relief, the watershed is underlain by a complex interconnected sequence of sand and gravel aquifers that are separated by discontinuous clayey aquitards. A steady-state condition was achieved in the model by calibrating the subsurface flow field to 16 observation wells where long-term hydraulic head data were available, while simultaneously establishing a level of baseflow discharge on the surface regime approximating the level observed at the beginning of the transient simulation period. The model is then subjected to several hundred hours of rainfall data and the resulting discharge hydrographs are compared with the measured hydrographs. The calculated subsurface hydraulic head distribution and surficial rainfall-runoff responses, respectively, were shown to agree moderately well with those observed in the system during this period. The impact of an upland surficial contaminant source discharging along a reach of a small stream within the subcatchment was also examined. Results showed that short-duration, high-intensity concentration peaks were not captured if annual or monthly average rainfall was used as input. The hydraulic head and concentration variations due to short-duration rainfall variations showed a muted response with increasing depth below the streambed due to the natural smoothing in the hydraulic response and to dispersion and diffusion of the solute, respectively. Discrete daily precipitation events were also found to cause rapid changes in the calculated water and solute exchange fluxes. The variability and sensitivity of these near-stream processes to the temporal resolution of rainfall input, specifically the concentration and solute exchange flux responses, may be significant in the prediction of health risks to aquatic habitats. Overall, it is concluded that the model is capable of reproducing surface and subsurface hydrodynamic processes at the subcatchment scale although the results could be better through improved parameterization of the subcatchment and the manner in which the model simulates evapotranspiration processes.

This paper offers a new theory and empirical testing of long-term trends of public expenditures for five countries. While Wagner’s Law would imply an exponential growth process of the ratio between public expenditures and national income (G/Y), the law should be rejected both on theoretical and empirical grounds, because it disregards the role of ever increasing distortionary taxation. However, under some conditions, the combination of Wagner’s Law and the Pigou’s conjecture that the excess burden of taxation constrains the growth of public expenditures can be captured by a non-linear first order differential equation. The equation is the Verhulst’s logistic, originally invented to model Malthusian predictions on population growth. The integration of a Verhulst equation generates an S-shaped curve. This analytical framework combines intuitions from a welfare economics and a public choice perspective, and potentially offers a new research strategy on the dynamics of government expenditures. We offer preliminary econometric estimates on long run trends (around 1870–1990) of G/Y in U.S., U.K., France, Germany, Italy. These estimates confirm a pattern of similar trajectories, in spite of different national parameters, and suggest that the logistic view of growth of government is consistent with observed data.

Fil: Villar, Carlos. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - La Plata. Instituto de Limnologia ; Argentina

Eating disorders often develop during adolescence and young adulthood, and are associated with significant psychological and physical burden. Identifying evidence-based interventions is critical and there is need to take stock of the extant literature, to inform clinical practice regarding well-researched interventions and to direct future research agendas by identifying gaps in the evidence base. Aim To investigate and quantify the nature and distribution of existing high-quality research on the prevention and treatment of eating disorders in young people using evidence mapping methodology. Method A systematic search for prevention and treatment intervention studies in adolescents and young adults (12–25 years) was conducted using EMBASE, PSYCINFO and MEDLINE. Studies were screened and mapped according to disorder, intervention modality, stage of eating disorder and study design. Included studies were restricted to controlled trials and systematic reviews published since 1980. Results The eating disorders evidence map included 197 trials and 22 systematic reviews. Prevention research was dominated by trials of psychoeducation (PE). Bulimia nervosa (BN) received the most attention in the treatment literature, with cognitive behavioural therapy (CBT) and antidepressants the most common interventions. For anorexia nervosa (AN), family based therapy (FBT) was the most studied. Lacking were trials exploring treatments for binge eating disorder (BED) and eating disorder not otherwise specified (EDNOS). Relapse prevention strategies were notably absent across the eating disorders. Conclusions Despite substantial literature devoted to the prevention and treatment of eating disorders in young people, the evidence base is not well established and significant gaps remain. For those identified as being at-risk, there is need for prevention research exploring strategies other than passive PE. Treatment interventions targeting BED and EDNOS are required, as are systematic reviews synthesising BN treatment trials (e.g., CBT, antidepressants). FBTs for AN require investigation against other validated psychological interventions, and the development of relapse prevention strategies is urgently required. By systematically identifying existing interventions for young people with eating disorders and exposing gaps in the current literature, the evidence map can inform researchers, funding bodies and policy makers as to the opportunities for future research.

Invasion ecology has been criticised for its lack of general principles. To explore this criticism, we conducted a meta-analysis that examined characteristics of invasiveness (i.e. the ability of species to establish in, spread to, or become abundant in novel communities) and invasibility (i.e. the susceptibility of habitats to the establishment or proliferation of invaders). There were few consistencies among invasiveness characteristics (3 of 13): established and abundant invaders generally occupy similar habitats as native species, while abundant species tend to be less affected by enemies; germination success and reproductive output were significantly positively associated with invasiveness when results from both stages (establishment/spread and abundance/impact) were combined. Two of six invasibility characteristics were also significant: communities experiencing more disturbance and with higher resource availability sustained greater establishment and proliferation of invaders. We also found that even though 'propagule pressure' was considered in only ∼29% of studies, it was a significant predictor of both invasiveness and invasibility (55 of 64 total cases). Given that nonindigenous species are likely introduced non-randomly, we contend that 'propagule biases' may confound current paradigms in invasion ecology. Examples of patterns that could be confounded by propagule biases include characteristics of good invaders and susceptible habitats, release from enemies, evolution of 'invasiveness', and invasional meltdown. We conclude that propagule pressure should serve as the basis of a null model for studies of biological invasions when inferring process from patterns of invasion. © Springer 2006.

An easy and rapid method for preparing biological targets for trace element analysis using nuclear techniques involving charged particle beams is described. The targets are thin, homogeneous and uniform. They withstand 100 nA of 1–2 MeV proton beams and of 5–10 MeV alpha beams for about 10 hrs.

A study of neutron and gamma interaction (in the low dose range) with L-phenylalanine in aqueous solutions shows that the main radiolytic pathway occurs through the attack of OH radicals. The products of the interaction are essentially tyrosine, Dopa and melanine in both cases. However, for gamma radiation there is a complete utilization of the OH radicals and the reaction pathway mainly proceeds by the sequence: phenylalanine»tyrosine»Dopa»melanine. On the contrary, for neutron radiation, the OH recombination is a rather efficient process and the prevailing pathway is: phenylalanine»Dopa»melanine.

Nuclear techniques are very useful in the simultaneous determination of many trace elements in biological samples; the sensitivity depends on the method and on the elements in study and in many cases is better than 0.1 ppm. Proton-induced X-ray fluorescence and α-particle elastic diffusion techniques are described; the methods of sample preparation, the sensitivity obtained and some experimental results are included.