Dynamic targeting enables domain-general inhibitory control over action and thought by the prefrontal cortex.

Over the last two decades, inhibitory control has featured prominently in accounts of how humans and other organisms regulate their behaviour and thought. Previous work on how the brain stops actions and thoughts, however, has emphasised distinct prefrontal regions supporting these functions, suggesting domain-specific mechanisms. Here we show that stopping actions and thoughts recruits common regions in the right dorsolateral and ventrolateral prefrontal cortex to suppress diverse content, via dynamic targeting. Within each region, classifiers trained to distinguish action-stopping from action-execution also identify when people are suppressing their thoughts (and vice versa). Effective connectivity analysis reveals that both prefrontal regions contribute to action and thought stopping by targeting the motor cortex or the hippocampus, depending on the goal, to suppress their task-specific activity. These findings support the existence of a domain-general system that underlies inhibitory control and establish Dynamic Targeting as a mechanism enabling this ability

Stochastic Modelling Approach to the Incubation Time of Prionic Diseases

Transmissible spongiform encephalopathies like the bovine spongiform encephalopathy (BSE) and the Creutzfeldt-Jakob disease (CJD) in humans are neurodegenerative diseases for which prions are the attributed pathogenic agents. A widely accepted theory assumes that prion replication is due to a direct interaction between the pathologic (PrPsc) form and the host encoded (PrPc) conformation, in a kind of an autocatalytic process. Here we show that the overall features of the incubation time of prion diseases are readily obtained if the prion reaction is described by a simple mean-field model. An analytical expression for the incubation time distribution then follows by associating the rate constant to a stochastic variable log normally distributed. The incubation time distribution is then also shown to be log normal and fits the observed BSE data very well. The basic ideas of the theoretical model are then incorporated in a cellular automata model. The computer simulation results yield the correct BSE incubation time distribution at low densities of the host encoded protein

Phase transition and landscape statistics of the number partitioning problem

The phase transition in the number partitioning problem (NPP), i.e., the transition from a region in the space of control parameters in which almost all instances have many solutions to a region in which almost all instances have no solution, is investigated by examining the energy landscape of this classic optimization problem. This is achieved by coding the information about the minimum energy paths connecting pairs of minima into a tree structure, termed a barrier tree, the leaves and internal nodes of which represent, respectively, the minima and the lowest energy saddles connecting those minima. Here we apply several measures of shape (balance and symmetry) as well as of branch lengths (barrier heights) to the barrier trees that result from the landscape of the NPP, aiming at identifying traces of the easy/hard transition. We find that it is not possible to tell the easy regime from the hard one by visual inspection of the trees or by measuring the barrier heights. Only the {\it difficulty} measure, given by the maximum value of the ratio between the barrier height and the energy surplus of local minima, succeeded in detecting traces of the phase transition in the tree. In adddition, we show that the barrier trees associated with the NPP are very similar to random trees, contrasting dramatically with trees associated with the $p$ spin-glass and random energy models. We also examine critically a recent conjecture on the equivalence between the NPP and a truncated random energy model

Asymmetric exclusion model with several kinds of impurities

We formulate a new integrable asymmetric exclusion process with $N-1=0,1,2,...$ kinds of impurities and with hierarchically ordered dynamics. The model we proposed displays the full spectrum of the simple asymmetric exclusion model plus new levels. The first excited state belongs to these new levels and displays unusual scaling exponents. We conjecture that, while the simple asymmetric exclusion process without impurities belongs to the KPZ universality class with dynamical exponent 3/2, our model has a scaling exponent $3/2+N-1$. In order to check the conjecture, we solve numerically the Bethe equation with N=3 and N=4 for the totally asymmetric diffusion and found the dynamical exponents 7/2 and 9/2 in these cases.Comment: to appear in JSTA

Fractal geometry of spin-glass models

Stability and diversity are two key properties that living entities share with spin glasses, where they are manifested through the breaking of the phase space into many valleys or local minima connected by saddle points. The topology of the phase space can be conveniently condensed into a tree structure, akin to the biological phylogenetic trees, whose tips are the local minima and internal nodes are the lowest-energy saddles connecting those minima. For the infinite-range Ising spin glass with p-spin interactions, we show that the average size-frequency distribution of saddles obeys a power law $\sim w^{-D}$, where w=w(s) is the number of minima that can be connected through saddle s, and D is the fractal dimension of the phase space

A contribuição do município de Guarulhos (estado de São Paulo) para a qualidade da água no Sistema Alto Tietê

The population growth in Guarulhos (São Paulo State) has been above the average for the São Paulo Metropolitan Region (RMSP). The Baquirivu-Guaçu River Basin (BHRBG), where the Baquirivu-Guaçu River is located, is exactly the urban expansion vector of Guarulhos municipality and neighboring areas. This study presents an analysis of the quality of the Baquirivu-Guaçu River waters at the entrance and at the exit of the Guarulhos municipality, in order to assess the effects of the implementation of sewage treatment plants (STPs) and land use on the Baquirivu-Guaçu River water quality between 2010 and 2014. For that were prepared the land use maps in the period analyzed, an analysis of the functioning of STPs in the study area, a statistical analysis of the Water Quality Index (WQI) and its parameters at different points of the river. The data relative to the Baquirivu-Guaçu River physico-chemicals and microbiological analyses indicate a much lower water quality in the exit of the Guarulhos municipality (WQI=16), when compared to that coming from the Arujá municipality (WQI=32). The mean values highlighted for BOD, DO, TU, TS and FC parameters indicate a considerable worsening of the Baquirivu-Guaçu River waters at point BQGU 03850. The values of TN, TP and pH parameters both at the entrance and exit of the basin are close. The analysis of land use evolution and water quality shows the consequences of an improper process of urban growth in the basin and that the domestic and industrial polluting sources represent considerable risk to water quality, attesting that the sanitation works carried out up to now have not been effective in reducing the polluting charges launched in the Baquirivu-Guaçu River waters.A contribuição do município de Guarulhos (Estado de São Paulo) para a qualidade de água do Sistema Alto Tietê. Guarulhos (SP) tem apresentado índices de crescimento populacional acima da média da Região Metropolitana de São Paulo (RMSP). A Bacia Hidrográfica do Rio Baquirivu Guaçu (BHRBG), onde se localiza o Rio Baquirivu Guaçu, é o vetor de expansão urbana do município e da região. Este trabalho apresenta uma análise da qualidade das águas do Rio Baquirivu-Guaçu na entrada e na saída do município de Guarulhos, avaliando os efeitos da implantação das ETEs e do uso da terra sobre a qualidade das águas do Rio Baquirivu-Guaçu, entre os anos de 2010 e 2014. Para isto foram elaborados os mapas de uso de terra no período analisado, uma análise do funcionamento das ETEs na área de estudo, e a análise estatística dos Índices de Qualidade de Águas (IQA) e de seus parâmetros nos diferentes pontos do rio. Os dados referentes às análises físico-química e microbiológica do Rio Baquirivu-Guaçu indicam uma qualidade de água na saída do município de Guarulhos (IQA=16), muito inferior àquela que recebe do município de Arujá (IQA=32). Os valores médios, em especial para os parâmetros DBO, OD, TU, ST e CF indicam uma piora na qualidade das águas do Rio Baquirivu-Guaçu no ponto BQGU03850. Os valores dos parâmetros NT, PT e pH foram muito próximos para ambos os pontos da entrada e saída da bacia. A análise entre a evolução do uso da terra e a qualidade da água demonstra as consequências do processo inadequado de crescimento urbano na bacia e que as fontes poluidoras domésticas e industriais representam considerável risco à qualidade das águas, demonstrando que as obras de saneamento realizadas até o momento não foram eficazes na redução de cargas poluidoras das águas do rio Baquirivu-Guaçu

Beneficial Effects of Long-Term Administration of an Oral Formulation of Angiotensin-(1–7) in Infarcted Rats

In this study was evaluated the chronic cardiac effects of a formulation developed by including angiotensin(Ang)-(1–7) in hydroxypropyl β-cyclodextrin (HPβCD), in infarcted rats. Myocardial infarction (MI) was induced by left coronary artery occlusion. HPβCD/Ang-(1–7) was administered for 60 days (76 μg/Kg/once a day/gavage) starting immediately before infarction. Echocardiography was utilized to evaluate usual cardiac parameters, and radial strain method was used to analyze the velocity and displacement of myocardial fibers at initial time and 15, 30, and 50 days after surgery. Real-time PCR was utilized to evaluate the fibrotic signaling involved in the remodeling process. Once-a-day oral HPβCD/Ang-(1–7) administration improved the cardiac function and reduced the deleterious effects induced by MI on TGF-β and collagen type I expression, as well as on the velocity and displacement of myocardial fibers. These findings confirm cardioprotective effects of Ang-(1–7) and indicate HPβCD/Ang-(1–7) as a feasible formulation for long-term oral administration of this heptapeptide

Tracing the origins of permitted emission lines in RU Lupi down to AU scales

Most of the observed emission lines and continuum excess from young accreting low mass stars (Classical T Tauri stars -- CTTSs) take place in the star-disk or inner disk region. These regions have a complex emission topology still largely unknown. In this paper the magnetospheric accretion and inner wind contributions to the observed permitted He and H near infrared (NIR) lines of the bright southern CTTS RU Lupi are investigated for the first time. Previous optical observations of RU Lupi showed a large H-alpha profile, due to the emission from a wind in the line wings, and a micro-jet detected in forbidden lines. We extend this analysis to NIR lines through seeing-limited high spectral resolution spectra taken with VLT/ISAAC, and adaptive optics (AO) aided narrow-band imaging and low spectral resolution spectroscopy with VLT/NACO. Using spectro-astrometric analysis we investigate the presence of extended emission down to very low spatial scales (a few AU). The HeI 10830 line presents a P Cygni profile whose absorption feature indicates the presence of an inner stellar wind. Moreover the spectro-astrometric analysis evidences the presence of an extended emission superimposed to the absorption feature and likely coming from the micro-jet detected in the optical. On the contrary, the origin of the Hydrogen Paschen and Brackett lines is difficult to address. We tried tentatively to explain the observed line profiles and flux ratios with both accretion and wind models showing the limits of both approaches. The lack of spectro-astrometric signal indicates that the HI emission is either compact or symmetric. Our analysis confirms the sensitivity of the HeI line to the presence of faint extended emission regions in the close proximity of the star.Comment: 11 pages, 4 figures, accepted for publication on A&

EMPREENDEDORISMO E EMPRESAS QUE DÃO SUPORTE AO EMPREENDEDOR

O presente artigo tem como tema a análise e a reflexão sobre “Empreendedorismo e Empresas que dão suporte ao empreendedor”. Assim, objetiva-se refletir sobre a importância da mudança de postura de administradores e empresas no sentido de aderir e incentivar cada vez mais posturas empreendedoras focadas na criação de novidades ou ainda de formas particulares de transformação de uma situação cercada de precariedades de recursos em um empreendimento de sucesso. Diante dessa assertiva, acredita-se que na atualidade os profissionais da área da administração devem repensar seus processos formativos e não mais tomar como referência única e exclusivamente as grandes empresas, mas formar profissionais que sejam capazes de em situações adversas fazer uso da criatividade e ajudar no desenvolvimento de projetos hoje situados no plano das micro e pequenas empresas. Para dar suporte às análises propostas ao longo desse texto, optou-se pelo uso da metodologia de pesquisa bibliográfica, que tem como princípio básico o desenvolvimento de uma revisão bibliográfica em que se discute o conceito de empreendedorismo no contexto atual, bem como definição de grupo/empresa empreendedora e, por fim, as características de uma empresa que dá suporte ao empreendedor. Acredita-se que a adoção de uma postura empreendedora independe dos fatores biológicos, mas podem ser treinados e desenvolvidos ao longo do processo formativo e profissional dos sujeitos, por isso os grupos empresariais podem, sim, dar suporte para que novas ideias revolucionem o mercado

Characterisation of the bacterial and fungal communities associated with different lesion sizes of Dark Spot Syndrome occurring in the Coral Stephanocoenia intersepta

The number and prevalence of coral diseases/syndromes are increasing worldwide. Dark Spot Syndrome (DSS) afflicts numerous coral species and is widespread throughout the Caribbean, yet there are no known causal agents. In this study we aimed to characterise the microbial communities (bacteria and fungi) associated with DSS lesions affecting the coral Stephanocoenia intersepta using nonculture molecular techniques. Bacterial diversity of healthy tissues (H), those in advance of the lesion interface (apparently healthy AH), and three sizes of disease lesions (small, medium, and large) varied significantly (ANOSIM R = 0.052 p,0.001), apart from the medium and large lesions, which were similar in their community profile. Four bacteria fitted into the pattern expected from potential pathogens; namely absent from H, increasing in abundance within AH, and dominant in the lesions themselves. These included ribotypes related to Corynebacterium (KC190237), Acinetobacter (KC190251), Parvularculaceae (KC19027), and Oscillatoria (KC190271). Furthermore, two Vibrio species, a genus including many proposed coral pathogens, dominated the disease lesion and were absent from H and AH tissues, making them candidates as potential pathogens for DSS. In contrast, other members of bacteria from the same genus, such as V. harveyii were present throughout all sample types, supporting previous studies where potential coral pathogens exist in healthy tissues. Fungal diversity varied significantly as well, however the main difference between diseased and healthy tissues was the dominance of one ribotype, closely related to the plant pathogen, Rhytisma acerinum, a known causal agent of tar spot on tree leaves. As the corals’ symbiotic algae have been shown to turn to a darker pigmented state in DSS (giving rise to the syndromes name), the two most likely pathogens are R. acerinum and the bacterium Oscillatoria, which has been identified as the causal agent of the colouration in Black Band Disease, another widespread coral disease