Fast oscillatory activity in the anterior cingulate cortex: dopaminergic modulation and effect of perineuronal net loss.

Dopamine release in the prefrontal cortex plays a critical role in cognitive function such as working memory, attention and planning. Dopamine exerts complex modulation on excitability of pyramidal neurons and interneurons, and regulates excitatory and inhibitory synaptic transmission. Because of the complexity of this modulation, it is difficult to fully comprehend the effect of dopamine on neuronal network activity. In this study, we investigated the effect of dopamine on local high-frequency oscillatory neuronal activity (in β band) in slices of the mouse anterior cingulate cortex (ACC). We found that dopamine enhanced the power of these oscillations induced by kainate and carbachol, but did not affect their peak frequency. Activation of D2R and in a lesser degree D1R increased the oscillation power, while activation of D4R had no effect. These high-frequency oscillations in the ACC relied on both phasic inhibitory and excitatory transmission and functional gap junctions. Thus, dopamine released in the ACC promotes high-frequency synchronized local cortical activity which is known to favor information transfer, fast selection and binding of distributed neuronal responses. Finally, the power of these oscillations was significantly enhanced after degradation of the perineuronal nets (PNNs) enwrapping most parvalbumin interneurons. This study provides new insights for a better understanding of the abnormal prefrontal gamma activity in schizophrenia (SZ) patients who display prefrontal anomalies of both the dopaminergic system and the PNNs.

Flash Memory Cells Reliability Parameters Investigation

The present work is a part of the large project with purpose to qualify the Flash memory for automotive application using a standardized test and measurement flow. High memory reliability and data retention are the most critical parameters in this application. The current work covers the functional tests and data retention test. The purpose of the data retention test is to obtain the data retention parameters of the designed memory, i.e. the maximum time of information storage at specified conditions without critical charge leakage. For this purpose the charge leakage from the cells, which results in decrease of cells threshold voltage, was measured after a long-time hightemperature treatment at several temperatures. The amount of lost charge for each temperature was used to calculate the Arrhenius constant and activation energy for the discharge process. With this data, the discharge of the cells at different temperatures during long time can be predicted and the probability of data loss after years can be calculated. The memory chips, investigated in this work, were 0.035 μm CMOS Flash memory testchips, designed for further use in the Systems-on-Chips for automotive electronics.

Sources of variability of speech, spatial, and qualities of hearing scale (SSQ) scores in normal-hearing and hearing-impaired populations.

OBJECTIVE: To identify and quantify sources of variability in scores on the speech, spatial, and qualities of hearing scale (SSQ) and its short forms among normal-hearing and hearing-impaired subjects using a French-language version of the SSQ. DESIGN: Multi-regression analyses of SSQ scores were performed using age, gender, years of education, hearing loss, and hearing-loss asymmetry as predictors. Similar analyses were performed for each subscale (Speech, Spatial, and Qualities), for several SSQ short forms, and for differences in subscale scores. STUDY SAMPLE: One hundred normal-hearing subjects (NHS) and 230 hearing-impaired subjects (HIS). RESULTS: Hearing loss in the better ear and hearing-loss asymmetry were the two main predictors of scores on the overall SSQ, the three main subscales, and the SSQ short forms. The greatest difference between the NHS and HIS was observed for the Speech subscale, and the NHS showed scores well below the maximum of 10. An age effect was observed mostly on the Speech subscale items, and the number of years of education had a significant influence on several Spatial and Qualities subscale items. CONCLUSION: Strong similarities between SSQ scores obtained across different populations and languages, and between SSQ and short forms, underline their potential international use.

Animal modelling for inherited central vision loss.

Disease-causing variants of a large number of genes trigger inherited retinal degeneration leading to photoreceptor loss. Because cones are essential for daylight and central vision such as reading, mobility, and face recognition, this review focuses on a variety of animal models for cone diseases. The pertinence of using these models to reveal genotype/phenotype correlations and to evaluate new therapeutic strategies is discussed. Interestingly, several large animal models recapitulate human diseases and can serve as a strong base from which to study the biology of disease and to assess the scale-up of new therapies. Examples of innovative approaches will be presented such as lentiviral-based transgenesis in pigs and adeno-associated virus (AAV)-gene transfer into the monkey eye to investigate the neural circuitry plasticity of the visual system. The models reported herein permit the exploration of common mechanisms that exist between different species and the identification and highlighting of pathways that may be specific to primates, including humans.

Welfare loss with municipal amalgamations and the willingness-to-pay for the municipality name

Functional advantages and drawbacks are commonly mentioned to rationally justify or condemn municipality amalgamations. However, many consolidation projects are resisted by local governments or citizens on the grounds that amalgamation would dampen local identity. A municipality's name change is probably the most visible sign of the loss of community bond experienced by citizens at amalgamation time. This article aims to put a value on this loss by measuring citizen willingness to pay for their city name. This methodological approach innovates upon the literature on municipal amalgamation and place branding by exploiting the versatility of the so-called contingent valuation method (CVM). CVM confronts respondents, in a survey setting, with a hypothetical market in which a characteristic of interest is exchanged. Here the characteristic is the possibility to retain one's city name for an amalgamated jurisdiction. The article presents the estimates provided by a survey conducted in four Swiss cities.

Consequences of lineage-specific gene loss on functional evolution of surviving paralogs: ALDH1A and retinoic acid signaling in vertebrate genomes

Genome duplications increase genetic diversity and may facilitate the evolution of gene subfunctions. Little attention, however, has focused on the evolutionary impact of lineage-specific gene loss. Here, we show that identifying lineage-specific gene loss after genome duplication is important for understanding the evolution of gene subfunctions in surviving paralogs and for improving functional connectivity among human and model organism genomes. We examine the general principles of gene loss following duplication, coupled with expression analysis of the retinaldehyde dehydrogenase Aldh1a gene family during retinoic acid signaling in eye development as a case study. Humans have three ALDH1A genes, but teleosts have just one or two. We used comparative genomics and conserved syntenies to identify loss of ohnologs (paralogs derived from genome duplication) and to clarify uncertain phylogenies. Analysis showed that Aldh1a1 and Aldh1a2 form a clade that is sister to Aldh1a3-related genes. Genome comparisons showed secondarily loss of aldh1a1 in teleosts, revealing that Aldh1a1 is not a tetrapod innovation and that aldh1a3 was recently lost in medaka, making it the first known vertebrate with a single aldh1a gene. Interestingly, results revealed asymmetric distribution of surviving ohnologs between co-orthologous teleost chromosome segments, suggesting that local genome architecture can influence ohnolog survival. We propose a model that reconstructs the chromosomal history of the Aldh1a family in the ancestral vertebrate genome, coupled with the evolution of gene functions in surviving Aldh1a ohnologs after R1, R2, and R3 genome duplications. Results provide evidence for early subfunctionalization and late subfunction-partitioning and suggest a mechanistic model based on altered regulation leading to heterochronic gene expression to explain the acquisition or modification of subfunctions by surviving ohnologs that preserve unaltered ancestral developmental programs in the face of gene loss.

Past climate-driven range shifts and population genetic diversity in arctic plants

AimHigh intra-specific genetic diversity is necessary for species adaptation to novel environments under climate change, but species tracking suitable conditions are losing alleles through successive founder events during range shift. Here, we investigated the relationship between range shift since the Last Glacial Maximum (LGM) and extant population genetic diversity across multiple plant species to understand variability in species responses. LocationThe circumpolar Arctic and northern temperate alpine ranges. MethodsWe estimated the climatic niches of 30 cold-adapted plant species using range maps coupled with species distribution models and hindcasted species suitable areas to reconstructions of the mid-Holocene and LGM climates. We computed the species-specific migration distances from the species glacial refugia to their current distribution and correlated distances to extant genetic diversity in 1295 populations. Differential responses among species were related to life-history traits. ResultsWe found a negative association between inferred migration distances from refugia and genetic diversities in 25 species, but only 11 had statistically significant negative slopes. The relationships between inferred distance and population genetic diversity were steeper for insect-pollinated species than wind-pollinated species, but the difference among pollination system was marginally independent from phylogenetic autocorrelation. Main conclusionThe relationships between inferred migration distances and genetic diversities in 11 species, independent from current isolation, indicate that past range shifts were associated with a genetic bottleneck effect with an average of 21% loss of genetic diversity per 1000km(-1). In contrast, the absence of relationship in many species also indicates that the response is species specific and may be modulated by plant pollination strategies or result from more complex historical contingencies than those modelled here.

Impact of the Femoral Head Position on Moment Arms in Total Hip Arthroplasty: A Parametric Finite Element Study.

BACKGROUND: Although the importance of accurate femoral reconstruction to achieve a good functional outcome is well documented, quantitative data on the effects of a displacement of the femoral center of rotation on moment arms are scarce. The purpose of this study was to calculate moment arms after nonanatomical femoral reconstruction. METHODS: Finite element models of 15 patients including the pelvis, the femur, and the gluteal muscles were developed. Moment arms were calculated within the native anatomy and compared to distinct displacement of the femoral center of rotation (leg lengthening of 10 mm, loss of femoral offset of 20%, anteversion ±10°, and fixed anteversion at 15°). Calculations were performed within the range of motion observed during a normal gait cycle. RESULTS: Although with all evaluated displacements of the femoral center of rotation, the abductor moment arm remained positive, some fibers initially contributing to extension became antagonists (flexors) and vice versa. A loss of 20% of femoral offset led to an average decrease of 15% of abductor moment. Femoral lengthening and changes in femoral anteversion (±10°, fixed at 15°) led to minimal changes in abductor moment arms (maximum change of 5%). Native femoral anteversion correlated with the changes in moment arms induced by the 5 variations of reconstruction. CONCLUSION: Accurate reconstruction of offset is important to maintaining abductor moment arms, while changes of femoral rotation had minimal effects. Patients with larger native femoral anteversion appear to be more susceptible to femoral head displacements.

Job loss among immigrant and native workers: evidence from Spain's economic downturn

The profound crisis that has affected the Spanish economy since mid - 2008 has been characterized by significant job losses and a marked rise in the country´s unemployment rate. However, unemployment has had a differential impact on different population groups. Compared to native, immigrant workers have experienced higher rates of job loss. Against this backdrop, this paper examines the differences between immigrants and natives (distinguished by gender) in terms of their probability of suffering job loss in the downturn of late 2008 and 2009. Our results indicate that the higher rate of job loss among female immigrant workers can be fully explained by their lower endowment of human capital. By contrast, human capital endowment and over-representation in certain occupations, sectors and regions in which the crisis had greatest impact do not appear to be the only reason for the penalty suffered by immigrant males in terms of their chances of losing their job in the downturn.

Population connectivity buffers genetic diversity loss in a seabird

Background Ancient DNA has revolutionized conservation genetic studies as it allows monitoring of the genetic variability of species through time and predicting the impact of ecosystems" threats on future population dynamics and viability. Meanwhile, the consequences of anthropogenic activities and climate change to island faunas, particularly seabirds, remain largely unknown. In this study, we examined temporal changes in the genetic diversity of a threatened seabird, the Cory"s shearwater (Calonectris borealis). Findings We analysed the mitochondrial DNA control region of ancient bone samples from the late-Holocene retrieved from the Canary archipelago (NE Atlantic) together with modern DNA sequences representative of the entire breeding range of the species. Our results show high levels of ancient genetic diversity in the Canaries comparable to that of the extant population. The temporal haplotype network further revealed rare but recurrent long-distance dispersal between ocean basins. The Bayesian demographic analyses reveal both regional and local population size expansion events, and this is in spite of the demographic decline experienced by the species over the last millennia. Conclusions Our findings suggest that population connectivity of the species has acted as a buffer of genetic losses and illustrate the use of ancient DNA to uncover such cryptic genetic events.

Coolant Flow and Heat Transfer in Pebble-Bed Reactor Core

This thesis gathers knowledge about ongoing high-temperature reactor projects around the world. Methods for calculating coolant flow and heat transfer inside a pebble-bed reactor core are also developed. The thesis begins with the introduction of high-temperature reactors including the current state of the technology. Process heat applications that could use the heat from a high-temperature reactor are also introduced. A suitable reactor design with data available in literature is selected for the calculation part of the thesis. Commercial computational fluid dynamics software Fluent is used for the calculations. The pebble-bed is approximated as a packed-bed, which causes sink terms to the momentum equations of the gas flowing through it. A position dependent value is used for the packing fraction. Two different models are used to calculate heat transfer. First a local thermal equilibrium is assumed between the gas and solid phases and a single energy equation is used. In the second approach, separate energy equations are used for the phases. Information about steady state flow behavior, pressure loss, and temperature distribution in the core is obtained as results of the calculations. The effect of inlet mass flow rate to pressure loss is also investigated. Data found in literature and the results correspond each other quite well, considered the amount of simplifications in the calculations. The models developed in this thesis can be used to solve coolant flow and heat transfer in a pebble-bed reactor, although additional development and model validation is needed for better accuracy and reliability.

Estudos da eletrodeposição de metais em regime de subtensão

This work reviews recent studies of underpotential deposition (UPD) of several metals on Pt and Au substrates performed in the Grupo de Materiais Eletroquímicos e Métodos Eletroanalíticos (IQSC -- USP, São Carlos). The UPD Cu, Cd and Pb on Pt were analysed in terms of their influence in the oxygen evolution reaction. Partial blockage of surface active sites, promoted by Pb ad-atoms, resulted in a change from water to hydrogen peroxide as the final product. The Ag UPD on Pt and Au substrates was also discussed in this work. A detailed model of charge calculation for Ag monolayer was developed and confirmed by the rotating ring-disk data. The partial charge transfer in UPD studies was analysed in the Cd/Pt and Cd/Au systems and a value of 0.5 was found for the adsorption electrovalence of Cd ad-ions. The Sn/Pt UPD systems were studied from the point of view of the valences of metallic ions in solution. The deposition from Sn(IV) generates a full monolayer with a maximum occupation of approximately 40% of the surface active sites (340 µC cm-2) plus 105 µC cm-2 of Hads (half monolayer). Changing the metallic ion for Sn(II), it was possible to deposit a full monolayer (210 µC cm-2) without any detectable Hads. Finally, the effect of anions was discussed in the Zn/Pt and Zn/Au systems. Here, the hydrogen evolution reaction (her) and the hydrogen adsorption/desorption were used in order to investigate the maximum coverage of the surface with Zn ad-atoms. The full monolayer, characterised by the complete absence of Hads, was achieved only in 0.5 M HF solutions.

Her onginþ seo boc: On the loss and retention of grammatical gender in Early Middle English

Tutkielma käsittelee kieliopillisen suvun säilymistä myöhäisessä muinaisenglannissa (Late Old English) ja varhaiskeskienglannissa (Early Middle English). Tutkielman tavoitteena on päätellä, kuinka kieliopillinen suku säilyy kolmessa muinaisenglannin/varhaiskeskienglannin aikakautta edustavassa tekstissä. Lähdeaineisto on valittu edustamaan aikaa (1150-1225), jolloin kieliopillisen suvun on sanottu kadonneen englannin kielestä. Lähdeaineisto myös edustaa kahta eri tekstilajia, ja tarjoaa siten aineistoa niiden väliseen vertailuun. Aineistosta on analysoitu nominien päätteitä, demonstratiivipronomineja sekä anaforisia persoonapronomineja, joissa substantiivien kieliopillinen suku näkyy. Osa anaforisista viittauksista on selitettävissä personifikaatiolla, jolloin elottomiin objekteihin tai käsitteisiin on liitetty inhimillistäviä piirteitä. Tutkimuksen perusteella kieliopillinen suku säilyy vielä joissakin muodoissa 1200- luvulle saakka. Merkittävää on aineistossa esiintyvä runsas vaihtelu ja pyhimyselämänkertojen ja lääketieteellisen tekstin väliset erot.