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Introduction: Data regarding laterality, focality, or total tumour diameter (TTD) in papillary thyroid cancer (PTC) are limited. We aimed to investigate the impact of focality, TTD, number of tumour foci, or laterality on aggressive features in PTC. Material and methods: Patients were categorized based on maximum tumour diameter (MTD) (≤ 10 vs. > 10 mm), focality, laterality, or the number of tumour foci (1/2/ ≥3). We also categorized the patients as follows: Group 1, unifocal microcarcinoma (MTD ≤ 10/TTD ≤ 10 mm); Group 2, multifocal microcarcinoma (MTD ≤ 10/TTD ≤ 10 mm); Group 3, multifocal microcarcinoma (MTD ≤ 10/TTD > 10 mm); Group 4, unifocal macrocarcinoma (MTD > 10/TTD > 10 mm); Group 5, multifocal macrocarcinoma (MTD > 10/TTD > 10 mm). Results: The mean diagnosis age (n = 511) was 44.7 (± 12.7) years, the majority of the patients were < 55 years old (n = 310) and female (n = 416). An increasing number of tumour foci were associated with a higher MTD or TTD, a higher ratio of extrathyroidal extension (ETE), vascular or lymphatic invasion, lymph node metastasis (LNM) or distant metastasis, or the need for radioactive iodine (RAI). There was no difference in the parameters between Group 3 and Group 2, or Group 4. Vascular invasion, American Thyroid Association high risk, LNM at diagnosis, and RAI total dose were higher in Group 5 than in Group 3. Microscopic or macroscopic ETE, T1b, and T4a were positive predictors for recurrence. Male sex, multifocality, number of tumour foci (≥ 3), MTD (> 10 mm), TTD (> 10 mm), Group 5, microscopic or macroscopic ETE, lymphatic or vascular invasion, RAI need, T2, and T4b were positive predictors for LNM. Conclusion: MTD and TTD increase the risk of LNM but not the recurrence in PTC. TTD, multifocality, and bilaterality can be considered risk factors in PTC staging systems and risk calculators.

Prospective memory (PM) allows us to form intentions and execute them in the future. Successful retrieval of prospective intentions depends on adequate context monitoring and disengagement from the ongoing task. These processes are also central in predicting incoming language information and guiding language production in bilinguals. We investigated if different bilingual experiences (early/late bilinguals, monolinguals) modulate performance in PM tasks that varied in attentional requirements (focal vs. non-focal). Behavioural and eventrelated potential (ERP) results indicated that early bilinguals differed from late bilinguals and monolinguals in how they performed the prospective task. Specifically, they showed larger differences between the ongoing activity and the prospective task in the N300 and P3b components when performing the more difficult non-focal PM task, indicating that they engaged in monitoring/updating to adapt to the task’s demands. These differences were not observed in late bilinguals and monolinguals, suggesting that prospective processing is dependent on the bilingual experience., Spanish Government FPU17/03378, Junta de Andalucia PSI 2017-89324-C2-2-P PGC2018-093786-B-I00 30B51801 A-CTS-111-UGR18/B-CTS-384-UGR20/P20_00107

Background Macroscopic portal vein thrombosis (PVT) is a major poor prognosis factor in patients with hepatocellular carcinoma (HCC), but constitute a heterogeneous group. Aims To examine blood and tumor parameters of 1667 HCC patients who had PVT to identify factors that could differentiate different survival subsets. Methods a large HCC database was examined for presence of patients with PVT and analyzed retrospectively for PVT-associated factors and prognosis. Results A logistic regression model was calculated for presence of PVT. Highest odds ratios were found for tumor multifocality and serum albumin levels, as well as serum alpha-fetoprotein (AFP) and bilirubin levels. A Kaplan-Meier and Cox model on survival also showed the highest hazard ratios for tumor multifocality and serum albumin. A model was constructed on all 4 possible combinations of tumor focality and serum albumin in PVT patients. The longest survival group had 3.5 g/dL. Conversely, the shortest survival group had >2 tumor nodules plus serum albumin, Highlights • Portal vein thrombosis (PVT) is a major poor prognosis factor in HCC patients. • We found that the highest odds ratios for PVT included number of tumor foci and serum albumin levels. • A model was constructed with all 4 possible combinations of these 2 parameters. • The longest survival group had 2 tumor nodules plus low albumin. These 2 PVT groups had a 3-fold difference in survival and had significantly different AFP and bilirubin levels. • These findings provide simple patient selection criteria for treating in PVT patients.

The aim of this study was to assess the prognostic value of the steroid hormone receptor expression, counting the retinoid X receptor (RXR) and thyroid hormone receptors (THRs), on the two different breast cancer (BC) entities: multifocal/multicentric versus unifocal. The overall and disease-free survival were considered as the prognosis determining aspects and analyzed by uni- and multi-variate analysis. Furthermore, histopathological grading and TNM staging (T = tumor size, N = lymph node involvement, M = distant metastasis) were examined in relation to RXR and THRs expression. A retrospective statistical analysis was carried out on survival-related events in a series of 319 sporadic BC patients treated at the Department of Gynecology and Obstetrics at the Ludwig-Maximillian&rsquo, s University in Munich between 2000 and 2002. The expression of RXR and THRs, including its two major isoforms THR&alpha, 1 and THR&alpha, 2, was analyzed by immunohistochemistry and showed to have a significant correlation for both BC entities in regard to survival analysis. Patients with multifocal/multicentric BC were exposed to a significantly worse disease-free survival (DFS) when expressing RXR. Patients with unifocal BC showed a significantly worse DFS when expressing THR&alpha, 1. In contrast, a statistically significant positive association between THR&alpha, 2 expression and enhanced DFS in multifocal/multicentric BC was shown. Especially the RXR expression in multifocal/multicentric BC was found to play a remarkably contradictory role for BC prognosis. The findings imply the need for a critical review of possible molecular therapies targeting steroid hormone receptors in BC treatment. Our results strengthen the need to further investigate the behavior of the nuclear receptor family, especially in relation to BC focality.

Transcranial magnetic stimulation (TMS) is a promising, non-invasive approach in the diagnosis and treatment of several neurological conditions. However, the specific results in the cortex of the magnitude and spatial distribution of the secondary electrical field (E-field) resulting from TMS at different stimulation sites/orientations and varied TMS parameters are not clearly understood. The objective of this study is to identify the impact of TMS stimulation site and coil orientation on the induced E-field, including spatial distribution and the volume of activation in the cortex across brain areas, and hence demonstrate the need for customized optimization, using a three-dimensional finite element model (FEM). A considerable difference was noted in E-field values and distribution at different brain areas. We observed that the volume of activated cortex varied from 3000 to 7000 mm3 between the selected nine clinically relevant coil locations. Coil orientation also changed the induced E-field by a maximum of 10%, and we noted the least optimal values at the standard coil orientation pointing to the nose. The volume of gray matter activated varied by 10% on average between stimulation sites in homologous brain areas in the two hemispheres of the brain. This FEM simulation model clearly demonstrates the importance of TMS parameters for optimal results in clinically relevant brain areas. The results show that TMS parameters cannot be interchangeably used between individuals, hemispheres, and brain areas. The focality of the TMS induced E-field along with its optimal magnitude should be considered as critical TMS parameters that should be individually optimized.

The aim of this study was to evaluate the prognostic impact of prostaglandin E2 receptor 3 (EP3) receptor expression might have on the two different breast cancer entities: multifocal/multicentric versus unifocal. As the prognosis determining aspects, we investigated the overall- and disease-free survival by uni-and multivariate analysis. To underline the study&rsquo, s conclusion, we additionally considered the histopathological grading and the tumor node metastasis (TNM) staging system. A retrospective statistical analysis was performed on survival related events in a series of 289 sporadic breast cancer (BC) patients treated at the Department of Obstetrics and Gynecology at the Ludwig&ndash, Maximillian&rsquo, s University in Munich between 2000 and 2002. The EP3 receptor expression was analyzed by immunohistochemistry and showed to have a significantly positive association with breast cancer prognosis for both entities, although with major differences. Patients with unifocal BC with EP3 receptor expression showed a significant improved overall survival, in contrast to the patient cohort with multifocal/multicentric BC. In this group, EP3 expression revealed its positive impact merely five years after initial diagnosis. Underlining the positive influence of EP3 as a positive prognosticator notably for unifocal breast cancer, only this patient cohort showed favorable outcomes in staging and grading. Especially EP3 expression in unifocal breast cancer was identified as an independent prognostic marker for the overall survival, when adjusted for age, grading, and staging. Altogether, our results strengthen the need to further investigate the behavior of EP3 in breast cancer and understand why markers linked to inflammation show different effects on prognosis and clinicopathological parameters on each focality type.

Представлена краткая характеристика ландшафтно-климатических особенностей зон, в которых отмечаются очаги аскаридоза. Проводились исследования природно-климатического и геолого-морфологического разнообразия Чеченской Республики в контексте расширяющего эпидемиологического значения в распространении аскаридоза. Исследованы пробы почвы на санитарно-химические, микробиологические и паразитологические показатели с целью оценки санитарно-гельминтологического состояния обсемененности яйцами глист. В целях выявления распространения гельминтозов в равнинной и горной части Чеченской Республики проведены обследования среди различных слоев населения. Проведен анализ степени распространения аскаридоза среди различных слоев населения, выявлены наиболее пораженные возрастные группы., A brief description of the landscape and climatic features of zones in which focus of ascariasis is noted is presented. Studies of the natural-climatic and geological-morphological diversity of Chechen Republic were conducted in the context of expanding epidemiological significance in the spread of ascariasis. Soil samples were studied for sanitary-chemical, microbiological and parasitological indicators in order to assess the sanitary-helminthological state of seed contamination with worm eggs. In order to identify the spread of helminthiases in the plain and mountainous parts of Chechen Republic, surveys were conducted among various segments of the population. The analysis of the degree of spread of ascariasis among various segments of the population was carried out, the most affected age groups were identified., №2(16) (2020)

Background: In transcranial direct current stimulation (TDCS), electric current is applied via two large electrodes to modulate brain activity. Computational models have shown that large electrodes produce diffuse electric fields (EFs) in the brain, which depends on individual head and brain anatomy. Recently, smaller electrodes as well as novel electrode arrangements, including high-definition TDCS (HD-TDCS) montages, have been introduced to improve the focality of EFs. Here, we investigated whether the EFs of focal montages are more susceptible to interindividual anatomical differences. Methods: Thirteen TDCS montages, including conventional M1-contralateral forehead montages with different stimulating electrode sizes as well as 4 × 1 HD and bipolar HD montages, producing varying EF focalities were modeled using the finite element method in 77 subjects, with individual anatomically realistic models based on magnetic resonance images. Results: Interindividual variability of predicted EFs increased with EF focality for conventional M1-contralateral forehead and 4 × 1 HD montages. 4 × 1 HD-TDCS was found to have the highest EF focality and greatest variability. Bipolar HD montages targeting the region between two small electrodes did not follow this pattern, but produced EF magnitudes comparable to those of 4× 1 HD-TDCS, with a minor decrease in focality and lower interindividual variability. Conclusions: EF focality in TDCS was achieved at the cost of increased interindividual variability. Hence, individual modeling is required to plan EF doses when focal montages are used. Among the studied montages, bipolar HD montages provided a compromise between inter-individual variability, focality and magnitude of the predicted EFs.

Large-scale synchronization of neural oscillations is a key mechanism for functional information exchange among brain areas. Dual-site Transcranial Alternating Current Stimulation (ds-TACS) has been recently introduced as non-invasive technique to manipulate the temporal phase relationship of local oscillations in two connected cortical areas. While the frequency of ds-TACS is matched, the phase of stimulation is either identical (in-phase stimulation) or opposite (anti-phase stimulation) in the two cortical target areas. In-phase stimulation is thought to synchronize the endogenous oscillations and hereby to improve behavioral performance. Conversely, anti-phase stimulation is thought to desynchronize neural oscillations in the two areas, which is expected to decrease performance. Critically, in- and anti-phase ds-TACS should only differ with respect to temporal phase, while all other stimulation parameters such as focality and stimulation intensity should be matched to enable an unambiguous interpretation of the behavioral effects. Using electric field simulations based on a realistic head geometry, we tested how well this goal has been met in studies, which have employed ds-TACS up to now. Separating the induced electrical fields in their spatial and temporal components, we investigated how the chosen electrode montages determined the spatial field distribution and the generation of phase variations in the injected electric fields. Considering the basic physical mechanisms, we derived recommendations for an optimized stimulation montage. The latter allows for a principled design of in- and anti-phase ds-TACS conditions with matched spatial distributions of the electric field. This knowledge will help cognitive neuroscientists to design optimal ds-TACS configurations, which are suited to probe unambiguously the causal contribution of phase coupling to specific cognitive processes in the human brain.

Transcranial electric stimulation (TES) can modulate intrinsic neural activity in the brain by injecting weak currents through electrodes attached to the scalp. TES has been widely used as a neuroscience tool to investigate how behavioural and physiological variables of brain function are modulated by electric stimulation of specific brain regions. For an unambiguous interpretation of TES experiments, it is important that the electric fields can be steered towards one or several brain regions-of-interest. However, the conductive proprieties of the human head impose inherent physical limitations on how focal the electric fields in the brain produced by multi-electrode TES can be. As a rule of thumb, it is not feasible to target deep brain areas with TES, although focusing the field in some specific deeper locations might be possible due to favourable conductive properties in the surrounding tissue. In the present study, we first propose a novel method for the automatic calculation of electrode placements and stimulation intensities to optimally affect a given target position. We provide a computationally efficient and robust implementation of the optimization procedure that is able to adhere to safety constraints, while explicitly controlling both the number of active electrodes and the angular deviation of the field in the target area relative to the desired field direction. Leveraging the high computational efficiency of our method, we systematically assess the achievable focality of multi-electrode TES for all cortex positions, thereby investigating the dependence on the chosen constraints. Our results provide comprehensive insight into the limitations regarding the achievable TES dose and focality that are imposed by the biophysical constraints and the safety considerations of TES., 45 pages, 10 figures. Updated to accepted version

Background In transcranial direct current stimulation (TDCS), electric current is applied via two large electrodes to modulate brain activity. Computational models have shown that large electrodes produce diffuse electric fields (EFs) in the brain, which depends on individual head and brain anatomy. Recently, smaller electrodes as well as novel electrode arrangements, including high-definition TDCS (HD-TDCS) montages, have been introduced to improve the focality of EFs. Here, we investigated whether the EFs of focal montages are more susceptible to interindividual anatomical differences. Methods Thirteen TDCS montages, including conventional M1-contralateral forehead montages with different stimulating electrode sizes as well as 4 × 1 HD and bipolar HD montages, producing varying EF focalities were modeled using the finite element method in 77 subjects, with individual anatomically realistic models based on magnetic resonance images. Results Interindividual variability of predicted EFs increased with EF focality for conventional M1-contralateral forehead and 4 × 1 HD montages. 4 × 1 HD-TDCS was found to have the highest EF focality and greatest variability. Bipolar HD montages targeting the region between two small electrodes did not follow this pattern, but produced EF magnitudes comparable to those of 4× 1 HD-TDCS, with a minor decrease in focality and lower interindividual variability. Conclusions EF focality in TDCS was achieved at the cost of increased interindividual variability. Hence, individual modeling is required to plan EF doses when focal montages are used. Among the studied montages, bipolar HD montages provided a compromise between inter-individual variability, focality and magnitude of the predicted EFs.

Prospective memory (PM) refers to remembering to perform intended actions in the future. Older adults in particular have been shown to be negatively affected by PM tasks that require a high amount of attentional resources (i.e., nonfocal tasks). This age-related PM deficit has been attributed to reduced target monitoring in this age group older adults. However, this conclusion was based on indirect measures of monitoring, such as costs of the ongoing task. The present study set out to 1) investigate older adults' PM target monitoring by, for the first time, employing a direct measure (i.e., eye tracking), 2) assess differences in monitoring between PM tasks that differ in their focality, and 3) examine whether differences in PM monitoring can indeed explain older adults' reduced PM performance in nonfocal tasks. Results demonstrate that while older, but not younger adults, showed reduced performance in a nonfocal PM task, overt monitoring (eye movements) of these groups did not differ between focality conditions. Further analyses showed that older adults' performance was still reduced on the strategically more demanding task after controlling for overt target monitoring (i.e., including only trials in which the participant monitored). In contrast to indirect measures of cue monitoring, our findings illustrate that older adults' deficits on non-focal PM tasks cannot (exclusively) be explained by reduced monitoring. Instead, processing that takes place after target monitoring are discussed as possible mechanisms underlying older adults' reduced PM performance in nonfocal tasks.

Studies investigating effects of acute stress on Prospective Memory (PM) so far yielded heterogeneous findings. Although results were commonly attributed to stress-induced changes in cortisol, past research did not disentangle effects of cortisol from the effects of sympathetic nervous system (SNS) activation and cognitive reappraisal. The present study therefore aimed at investigating the mere effect of cortisol on PM tasks that differently involve prefrontal brain regions (nonfocal vs. focal PM tasks) via a placebo-controlled oral pharmacological intake of 10 mg hydrocortisone mimicking physiological responses to stress. Contrary to our prediction, enhanced levels of cortisol did not affect PM accuracy and monitoring costs, neither for the focal nor the nonfocal PM tasks. These results suggest that changes of cortisol levels do not underlie potential stress effects on PM. Further exploratory results revealed that PM performance was higher in the 3 pm than in the 1 pm placebo group. This means that PM performance, independently of effects of cortisol, seem to vary throughout the day.

Knowing the gender of a counterpart can be focal in the willingness to collaborate in team settings that resemble the classic coordination problem. This paper explores whether knowing a co-worker’s gender affects coordination on the mutually beneficial outcome in a socially risky environment. In an experimental setting, subjects play a one-shot stag hunt game framed as a collaborative task in which they can “work together” or “work alone.” We exogenously vary whether workers know the gender of their counterparts pre-play. When gender is revealed, female players tend to gravitate to collaboration and efficient coordination regardless of the knowledge. Males, when knowingly paired with another male, tend to collaborate less, and thus, are less likely to coordinate on the Pareto optimal outcome. These results demonstrate one way that gender focality can lead to inefficient outcomes and provide insight for organizations looking to induce collaboration among workers.

Large river valleys have long been seen as important factors to shape the mobility, communication, and exchange of Pleistocene hunter-gatherers. However, rivers have been debated as either natural entities people adapt and react to or as cultural and meaningful entities people experience and interpret in different ways. Here, we attempt to integrate both perspectives. Building on theoretical work from various disciplines, we discuss the relationship between biophysical river properties and sociocultural river semantics and suggest that understanding a river’s persona is central to evaluating its role in spatial organization. By reviewing the literature and analyzing European Upper Paleolithic site distribution and raw material transfer patterns in relation to river catchments, we show that the role of prominent rivers varies considerably over time. Both ecological and cultural factors are crucial to explaining these patterns. Whereas the Earlier Upper Paleolithic record displays a general tendency toward conceiving rivers as mobility guidelines, the spatial consolidation process after the colonization of the European mainland is paralleled by a trend of conceptualizing river regimes as frontiers, separating archaeological entities, regional groups, or local networks. The Late Upper Paleolithic Magdalenian, however, is characterized again by a role of rivers as mobility and communication vectors. Tracing changing patterns in the role of certain river regimes through time thus contributes to our growing knowledge of human spatial behavior and helps to improve our understanding of dynamic and mutually informed human-environment interactions in the Paleolithic. Electronic supplementary material The online version of this article (doi:10.1007/s10816-015-9263-x) contains supplementary material, which is available to authorized users.

Background In transcranial magnetic stimulation (TMS) a strong, brief current pulse driven through a coil is used for non-invasively stimulating the cortex. Properties of the electric field (E-field) induced by the pulse together with physiological parameters determine the outcome of the stimulation. In research and clinical use, TMS is delivered using a wide range of different coils and stimulator units, all having their own characteristics; however, the parameters of the induced E-field are often inadequately known by the user. Objective To better understand how the use of a specific TMS device may affect the resulting cortical stimulation, our objective was to develop an instrument for automated measurement of the E-fields induced by TMS coils in spherically symmetric conductors approximating the head. Methods We built a saline-free, robotized measurement tool based on the triangle construction. The 5-mm-wide measurement probe allows complete sampling of the induced E-field at the studied depth. We used the instrument to characterize TMS coils and stimulators made by two companies. Results The measurements revealed that all tested stimulators performed as expected, but we also found significant differences between the different stimulators. Measurements of different coil specimens of the same stimulator models agreed with each other. Conclusion The presented TMS calibrator allows a straightforward characterization of the E-fields induced by TMS coils. By performing measurements using this kind of a tool helps in ensuring that an investigator knows the properties of the E-field.

Identifying the neurocognitive mechanisms that lead individuals remembering to execute an intention at the right moment (prospective memory, PM) and how such mechanisms are influenced by the features of that intention is a fundamental theoretical challenge. In particular, the functional contribution of subcortical regions to PM is still unknown. This study was aimed at investigating the role of the medial subdivision of the mediodorsal thalamic nucleus (mMDT) in PM, with particular focus on the processes that are mediated by the projections from/to this structure. We analysed the performance of a patient (OG) with a right-sided lesion involving the mMDT in a series of PM tasks that varied for focality (i.e., overlapping of processes for the PM and ongoing tasks) and emotional valence of the stimuli, comparing the patient's performance with that of a control group. We found that the mMDT damage led to deficits in PM that were modulated by focality and emotional valence. OG indeed showed: a greater cost in the ongoing performance when a non-focal PM task was added; a slowing down in retrieving the intentions, in particular when these were associated with focal PM cues; an abnormal performance in the task with positive PM cues. Our findings provide evidence of a contribution of mMDT to PM and suggest a modulation of prefrontal-dependent strategic monitoring and a possible interaction with the limbic structures in the integration of emotion and PM processes. They also give support to the still controversial idea that connections with the perirhinal cortex mediate familiarity-based recognition.

Background: Various transcranial magnetic stimulation (TMS) coil designs are available or have been proposed. However, key coil characteristics such as electric field focality and attenuation in depth have not been adequately compared. Knowledge of the coil focality and depth characteristics can help TMS researchers and clinicians with coil selection and interpretation of TMS studies. Objective: To quantify the electric field focality and depth of penetration of various TMS coils. Methods: The electric field distributions induced by 50 TMS coils were simulated in a spherical human head model using the finite element method. For each coil design, we quantified the electric field penetration by the half-value depth, d1/2, and focality by the tangential spread, S1/2, defined as the half-value volume (V1/2) divided by the half-value depth, S1/2 = V1/2/d1/2. Results: The 50 TMS coils exhibit a wide range of electric field focality and depth, but all followed a depth–focality tradeoff: coils with larger half-value depth cannot be as focal as more superficial coils. The ranges of achievable d1/2 are similar between coils producing circular and figure-8 electric field patterns, ranging 1.0–3.5 cm and 0.9–3.4 cm, respectively. However, figure-8 field coils are more focal, having S1/2 as low as 5 cm2 compared to 34 cm2 for circular field coils. Conclusions: For any coil design, the ability to directly stimulate deeper brain structures is obtained at the expense of inducing wider electrical field spread. Novel coil designs should be benchmarked against comparison coils with consistent metrics such as d1/2 and S1/2.

The present work investigated the role of mnemonic and executive factors on age-related PM. The impact of task switching, maintenance load combined with focality as well as target distinctiveness, again combined with focality was investigated in three different experiments in younger and older adults. Results show task switching as well as distinctiveness to be strongly linked to age effects in PM. Age effects were found when task switching demands were high, but not when these were low. Target distinctiveness affected age-related differences with age effects being higher for distinct than for non-distinct cues. Focality only impacted the age-related general task approach, particularly the differential recruitment of controlled attention to monitor for the cue in younger and older adults, but not age differences in PM. Moreover, the memory factor maintenance load did not relate to age differences. Findings suggest that cognitive control processes rather than memory processes explain PM age differences.

Background In transcranial magnetic stimulation (TMS), the stimulation-coil current is typically increased from 0 to over 5000 A in less than 100 μs. At the peak current, the energy stored in the magnetic field is over 300 J. Thus, the average power during a pulse exceeds 3 MW; the stimulator needs to be built from high-power electronics. The power requirements often limit the duration and frequency of repetitive TMS, for example, via coil heating. Objective We introduce a method for finding the minimum-energy solution for a TMS coil with given focality constraints. Methods This optimization is performed by using a spherically symmetric head model and by expressing the coil as a continuous surface current density, which is eventually discretized to form the coil windings. For the optimization, we defined TMS focality separately for the directions parallel and perpendicular to the field direction at the maximum of induced electric field. Results The computational model used for optimization was verified by manufacturing a prototype coil and measuring the electric field it induces in a spherically symmetric conductor. The optimized coil design requires significantly less power than existing TMS coil designs (a 73% reduction compared to an existing TMS coil with similar focality). Conclusion The described method allows for more efficient, more focal TMS coils, which may reduce coil heating and the coil click.

International audience; Neighboring formants in the three high vowels in French, F1/F2 for /u/ (↓F1⇓F2)400Hz, F2/F3 for /y/ (F2⇓F3)1900Hz, and F3/F4 for /i/ (⇑F3F4)3200Hz), as well as F1 and F2 in the back vowels /o ɔ ɑ/, aregrouped and therefore their intensity is reinforced (Schwartz et al., 1997; Vaissière, 2011). By contrast, neither /i/ and /u/ are focal in English. Flege (1987) shows that the French /u/, which he considers as a "similar" phone (to the English /u/), is more difficult to learn to pronounce like native speakers than /y/, which is a "new" phone with no equivalent in the learners' L1. Levy's (2009) data confirm this tendency.This talk will show how subtle acoustic differences between native speakers' and L2 learners' speech, underlying the perception of a foreign accent, can be illustrated with the aid of sound spectrography. The close vowels uttered by natives speakers of English learning L2 French reading the Aesop's fable "the North Wind and the Sun" / "la bise et le soleil" in the learner corpus SITAF will be taken as a starting point.A similar difficulty that Japanese-speaking learners of French encounter in learning to pronounce the French /u/ (Kamiyama and Vaissière, 2009) will also be shown based on the IPFC corpus.The effect of the consonantal context, as shown in Levy (2009), is illustrated for both languages and the relationship with articulation by the help of articulatory modeling.

The state price density of a basket, even under uncorrelated Black-Scholes dynamics, does not allow for a closed from density. (This may be rephrased as statement on the sum of lognormals and is especially annoying for such are used most frequently in Financial and Actuarial Mathematics.) In this note we discuss short time and small volatility expansions, respectively. The method works for general multi-factor models with correlations and leads to the analysis of a system of ordinary (Hamiltonian) differential equations. Surprisingly perhaps, even in two asset Black-Scholes situation (with its flat geometry), the expansion can degenerate at a critical (basket) strike level; a phenomena which seems to have gone unnoticed in the literature to date. Explicit computations relate this to a phase transition from a unique to more than one "most-likely" paths (along which the diffusion, if suitably conditioned, concentrates in the afore-mentioned regimes). This also provides a (quantifiable) understanding of how precisely a presently out-of-money basket option may still end up in-the-money., Comment: Appeared in: Large Deviations and Asymptotic Methods in Finance, Springer proceedings in Mathematics & Statistics, Editors: Friz, P.K., Gatheral, J., Gulisashvili, A., Jacquier, A., Teichmann, J., 2015, with minor typos removed

La focalidad es una dimensión informativa del lenguaje, que se materializa en la introducción de epicentros referenciales. Su estudio ha originado una terminología profusa para definir la función y denominar sus diversas expresiones y mecanismos de codificación. La profusión ha venido acompañada de importantes desacuerdos y notorias contradicciones en el empleo de la conceptualización más difundida. Admitiendo que se trata de un tema complejo y en el cual falta aún mucha investigación, nos proponemos llegar a ciertas sistematizaciones que permitan aclarar parte de la confusión terminológica y estructurar la función focal en sus aspectos centrales o mejor conocidos. A través de una revisión crítica de bibliografía relevante, se delimitarán los componentes centrales del problema, los cuales serán ilustrados y examinados en una muestra de español de Chile. El análisis se desarrollará sobre la base de principios y descriptores de carácter funcional, orientación donde las funciones informativas de la cláusula tienen un lugar privilegiado. Entre los resultados más importantes se puede adelantar, primeramente, la existencia de una gradiente focal, tanto en los efectos referenciales del proceso como en la organización y funcionamiento de sus formas más comunes de instanciación. También merece destacarse la significativa contribución del factor acústico, el cual demuestra un rendimiento mucho más significativo que el mencionado por la bibliografía en materia de codificación focal. A esto se suma su importante papel en la distinción de procesos informativos relacionados con la focalización, como la tematización y la topicalización. Focality is an informative dimension of language which is expressed in the introduction of referential epicenters. Its study has given rise to extensive terminology for defining its functions and naming its various expressions and codification mechanisms. This profusion of terminology has been accompanied by important disagreements and by evident contradictions in the use of the most significant conceptualizations. Because it is a complex topic that has not been researched extensively, a systematization that will clarify part of the confusing terminology and that will organize the focal function according to its central, or best-known, aspects is suggested. The central components of the problem, illustrated and analyzed in a sample of Chilean Spanish, will be delimited by means of a critical review of relevant literature. The analysis will be carried out within the framework of functional principles and descriptors, an approach in which the informative functions of the clause are crucial. Among the most significant findings are the existence of a focal gradient in both the referential effects of the process and the organization and functioning of its most common forms of instantiation. Also worthy of note is the significant role of the acoustic factor, which makes a far more important contribution to focus codification than what the literature indicates, while distinguishing focalization-related processes, such as thematization and topicalization.

The spatial resolution of conventional transcranial direct current stimulation (tDCS) is considered to be relatively diffuse owing to skull dispersion. However, we show that electric fields may be clustered at distinct gyri/sulci sites because of details in tissue architecture/conductivity, notably cerebrospinal fluid (CSF). We calculated the cortical electric field/current density magnitude induced during tDCS using a high spatial resolution (1 mm3) magnetic resonance imaging (MRI)-derived finite element human head model; cortical gyri/sulci were resolved. The spatial focality of conventional rectangular-pad (7 x 5 cm2) and the ring (4 x 1) electrode configurations were compared. The rectangular-pad configuration resulted in diffuse (unfocal) modulation, with discrete clusters of electric field magnitude maxima. Peak-induced electric field magnitude was not observed directly underneath the pads, but at an intermediate lobe. The 4 x 1 ring resulted in enhanced spatial focality, with peak-induced electric field magnitude at the sulcus and adjacent gyri directly underneath the active electrode. Cortical structures may be focally targeted by using ring configurations. Anatomically accurate high-resolution MRI-based forward-models may guide the "rational" clinical design and optimization of tDCS.

ObjectiveCoils designed for transcranial magnetic stimulation (TMS) must incorporate trade-offs between the required electrical power or energy, focality and depth penetration of the induced electric field (E-field), coil size, and mechanical properties of the coil, as all of them cannot be optimally met at the same time. In multi-locus TMS (mTMS), a transducer consisting of several coils allows electronically targeted stimulation of the cortex without physically moving a coil. In this study, we aimed to investigate the relationship between the number of coils in an mTMS transducer, the focality of the induced E-field, and the extent of the cortical region within which the location and orientation of the maximum of the induced E-field can be controlled.ApproachWe applied convex optimization to design planar and spherically curved mTMS transducers of different E-field focalities and analyzed their properties. We characterized the trade-off between the focality of the induced E-field and the extent of the cortical region that can be stimulated with an mTMS transducer with a given number of coils.Main resultsAt the expense of the E-field focality, one can, with the same number of coils, design an mTMS transducer that can control the location and orientation of the peak of the induced E-field within a wider cortical region.SignificanceWith E-fields of moderate focality, the problem of electronically targeted TMS becomes considerably easier compared with highly focal E-fields; this may speed up the development of mTMS and the emergence of new clinical and research applications.