Word contexts enhance the neural representation of individual letters in early visual cortex

Visual context facilitates perception, but how this is neurally implemented remains unclear. One example of contextual facilitation is found in reading, where letters are more easily identified when embedded in a word. Bottom-up models explain this word advantage as a post-perceptual decision bias, while top-down models propose that word contexts enhance perception itself. Here, we arbitrate between these accounts by presenting words and nonwords and probing the representational fidelity of individual letters using functional magnetic resonance imaging. In line with top-down models, we find that word contexts enhance letter representations in early visual cortex. Moreover, we observe increased coupling between letter information in visual cortex and brain activity in key areas of the reading network, suggesting these areas may be the source of the enhancement. Our results provide evidence for top-down representational enhancement in word recognition, demonstrating that word contexts can modulate perceptual processing already at the earliest visual regions

Eye drop Self-medication: Comparative Questionnaire-based study of two Latin American cities.

A broad spectrum of ocular symptoms are treated by self-medication with commercial eye-drops.  This behavior threatens individuals' visual health. In Latin America, evidence is poor. Objective:  To  detect,  characterize  and  compare  patterns  of  ophthalmic  self-medication  between  Córdoba (Argentina) and Barranquilla (Colombia).Design:  Analytic, cross-sectional and comparative population-based study. Setting: Two private tertiary care ophthalmology centers from Córdoba, Argentina, and Barranquilla, Colombia.Participants:  Patients 18 years of age or older who consulted for the first time in this two institutions duringAugust-November 2009, were included. A number of 570 patients were enrrolled.Methods:  Data collected through a semi-structured questionnaire. Main outcome measure: To determine thefrequency of self-medication with eyedrops on a specific population of two cities in Latin America.Results:  Comparable  rates  of  ocular  self-medication  were  found  (25.6%  and  25.7%  for  Cordoba  and Barranquilla, respectively). The percentage of men and women who self-medicated was not significantly different between both samples. The major source of eye drops recommendation in the Argentineans patients was the pharmacist (31%); while the social source was predominant in Colombian individuals (53%). In Cordoba, the most frequently used product was a non-steroidal anti-inflammatory drop in combination with a vasoconstrictive agent (32%); while in Barranquilla, antibiotic eye drops were preferred (33%). Self-medication was higher between the ages of 31 and 50 years old in Argentinean citizens (28%) and between 18 to 31 years old in the Colombiancommunity (39%). This habit was found mostly in patients who completed university studies in Cordoba (33%); in Barranquilla, individuals with lower educational level practice more this behavior (36%).Conclusion:  In both populations, patients commonly treat ocular conditions by self-medicating. Currently, anincreasing number of eye drops are obtainable without prescription and a high percentage of self-medicated patients in both samples ignore the possible side effects of the used medication.Fil: Marquez, Gabriel. Fundación VER; ArgentinaFil: Hildegard Piñeros-Heilbron. Fundación Oftalmológica del Caribe; ColombiaFil: Sanchez, Victoria M.. Fundación VER; ArgentinaFil: Torres, Victor Eduardo Roque. Fundación VER; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Estudios sobre Cultura y Sociedad. Universidad Nacional de Córdoba. Centro de Investigaciones y Estudios sobre Cultura y Sociedad; ArgentinaFil: Gramajo, Ana L.. Fundación VER; ArgentinaFil: Juarez, Claudio P.. Fundación VER; Argentina. Fundación Oftalmológica del Caribe; ColombiaFil: Peña, Fernando. Fundación Oftalmológica del Caribe; ColombiaFil: Luna, José D.. Fundación VER; Argentin

Comparative analysis on strains in asphalt pavement design using linear elastic and viscoelastic theories

In Colombia it is common to design pavements using the AASHTO 93 method and to complement it with an elastic analysis of the deformations that cause fatigue and rutting; this has repercussions on the behavior of the structure since it does not take into account the viscoelastic behavior of the asphalt mixtures, In this research, a comparison of three structures at different velocity ranges is made to compare the variation in fatigue and rutting concerning the traditional method of analysis in Colombia and to analyze the differences that may occur in linear elastic analysis and viscoelastic analysis of rutting and fatigue

Sociology and postcolonialism: another 'missing' revolution?

Sociology is usually represented as having emerged alongside European modernity. The latter is frequently understood as sociology's special object with sociology itself a distinctively modern form of explanation. The period of sociology's disciplinary formation was also the heyday of European colonialism, yet the colonial relationship did not figure in the development of sociological understandings. While the recent emergence of postcolonialism appears to have initiated a reconsideration of understandings of modernity, with the development of theories of multiple modernities, I suggest that this engagement is more an attempt at recuperating the transformative aspect of postcolonialism than engaging with its critiques. In setting out the challenge of postcolonialism to dominant sociological accounts, I also address `missing feminist/queer revolutions', suggesting that by engaging with postcolonialism there is the potential to transform sociological understandings by opening up a dialogue beyond the simple pluralism of identity claims

Relational victimization, friendship, and adolescents' hypothalamic–pituitary–adrenal axis responses to an in vivo social stressor

Adolescents’ peer experiences may have significant associations with biological stress-response systems, adding to or reducing allostatic load. This study examined relational victimization as a unique contributor to reactive hypothalamic–pituitary–adrenal (HPA) axis responses as well as friendship quality and behavior as factors that may promote HPA recovery following a stressor. A total of 62 adolescents (ages 12–16; 73% female) presenting with a wide range of life stressors and adjustment difficulties completed survey measures of peer victimization and friendship quality. Cortisol samples were collected before and after a lab-based interpersonally themed social stressor task to provide measures of HPA baseline, reactivity, and recovery. Following the stressor task, adolescents discussed their performance with a close friend; observational coding yielded measures of friends’ responsiveness. Adolescents also reported positive and negative friendship qualities. Results suggested that higher levels of adolescents’ relational victimization were associated with blunted cortisol reactivity, even after controlling for physical forms of victimization and other known predictors of HPA functioning (i.e., life stress or depressive symptoms). Friendship qualities (i.e., low negative qualities) and specific friendship behaviors (i.e., high levels of responsiveness) contributed to greater HPA regulation; however, consistent with theories of rumination, high friend responsiveness in the context of high levels of positive friendship quality contributed to less cortisol recovery. Findings extend prior work on the importance of relational victimization and dyadic peer relations as unique and salient correlates of adaptation in adolescence

Philosophy and Science in Leibniz

This paper explores the question of Leibniz’s contribution to the rise of modern ‘science’. To be sure, it is now generally agreed that the modern category of ‘science’ did not exist in the early modern period. At the same time, this period witnessed a very important stage in the process from which modern science eventually emerged. My discussion will be aimed at uncovering the new enterprise, and the new distinctions which were taking shape in the early modern period under the banner of the old Aristotelian terminology. I will argue that Leibniz begins to theorize a distinction between physics and metaphysics that tracks our distinction between the autonomous enterprise of science in its modern meaning, and the enterprise of philosophy. I will try to show that, for Leibniz, physics proper is the study of natural phenomena in mathematical and mechanical terms without recourse for its explanations to metaphysical notions. This autonomy, however, does not imply for Leibniz that physics can say on its own all that there is to be said about the natural world. Quite the opposite. Leibniz inherits from the Aristotelian tradition the view that physics needs metaphysical roots or a metaphysical grounding. For Leibniz, what is ultimately real is reached by metaphysics, not by physics. This is, in my view, Leibniz’s chief insight: the new mathematical physics is an autonomous enterprise which offers its own kind of explanations but does not exhaust what can (and should) be said about the natural world

Peer Influence and Nonsuicidal Self Injury: Longitudinal Results in Community and Clinically-Referred Adolescent Samples

Research suggests that adolescents' engagement in nonsuicidal self-injurious (NSSI) behaviors may be increasing over time, yet little is known regarding distal longitudinal factors that may promote engagement in these behaviors. Data from two longitudinal studies are presented to examine whether NSSI may be associated with peer influence processes. Study 1 included 377 adolescents from a community-based sample; Study 2 included 140 clinically-referred adolescents recruited from a psychiatric inpatient facility. In Study 1, adolescents' NSSI was examined at baseline and one year later. Adolescents' nominated best friend reported their own levels of NSSI. In Study 2, adolescents' NSSI was examined at baseline as well as 9 and 18-months post-baseline. Adolescents' perceptions of their friends' engagement in self-injurious behavior (including suicidality) and depressed mood also were examined at all three time points. Baseline depressive symptoms were measured in both studies; gender and age were examined as moderators of peer influence effects. Results from both studies supported longitudinal peer socialization effects of friends' self-injurious behavior on adolescents' own NSSI for girls, but not for boys, even after controlling for depressive symptoms as a predictor. Study 1 suggested socialization effects mostly for younger youth. Results from Study 2 also suggested longitudinal socialization effects, as well as peer selection effects; adolescents' NSSI was associated with increasing perceptions of their friends' engagement in depressive/self-injurious thoughts and behavior. Findings contribute to the nascent literature on longitudinal predictors of NSSI and to work on peer influence

Vitamin D and COVID-19 severity and related mortality: a prospective study in Italy

Background: Vitamin D deficiency has been suggested to favor a poorer outcome of Coronavirus disease-19 (COVID-19). We aimed to assess if 25-hydroxyvitamin-D (25OHD) levels are associated with interleukin 6 (IL-6) levels and with disease severity and mortality in COVID-19. Methods: We prospectively studied 103 in-patients admitted to a Northern-Italian hospital (age 66.1 ± 14.1 years, 70 males) for severely-symptomatic COVID-19. Fifty-two subjects with SARS-CoV-2 infection but mild COVID-19 symptoms (mildly-symptomatic COVID-19 patients) and 206 subjects without SARS-CoV-2 infection were controls. We measured 25OHD and IL-6 levels at admission and focused on respiratory outcome during hospitalization. Results: Severely-symptomatic COVID-19 patients had lower 25OHD levels (18.2 ± 11.4 ng/mL) than mildly-symptomatic COVID-19 patients and non-SARS-CoV-2-infected controls (30.3 ± 8.5 ng/mL and 25.4 ± 9.4 ng/mL, respectively, p < 0.0001 for both comparisons). 25OHD and IL-6 levels were respectively lower and higher in severely-symptomatic COVID-19 patients admitted to intensive care Unit [(ICU), 14.4 ± 8.6 ng/mL and 43.0 (19.0–56.0) pg/mL, respectively], than in those not requiring ICU admission [22.4 ± 1.4 ng/mL, p = 0.0001 and 16.0 (8.0–32.0) pg/mL, p = 0.0002, respectively]. Similar differences were found when comparing COVID-19 patients who died in hospital [13.2 ± 6.4 ng/mL and 45.0 (28.0–99.0) pg/mL] with survivors [19.3 ± 12.0 ng/mL, p = 0.035 and 21.0 (10.5–45.9) pg/mL, p = 0.018, respectively). 25OHD levels inversely correlated with: i) IL-6 levels (ρ − 0.284, p = 0.004); ii) the subsequent need of the ICU admission [relative risk, RR 0.99, 95% confidence interval (95%CI) 0.98–1.00, p = 0.011] regardless of age, gender, presence of at least 1 comorbidity among obesity, diabetes, arterial hypertension, creatinine, IL-6 and lactate dehydrogenase levels, neutrophil cells, lymphocytes and platelets count; iii) mortality (RR 0.97, 95%CI, 0.95–0.99, p = 0.011) regardless of age, gender, presence of diabetes, IL-6 and C-reactive protein and lactate dehydrogenase levels, neutrophil cells, lymphocytes and platelets count. Conclusion: In our COVID-19 patients, low 25OHD levels were inversely correlated with high IL-6 levels and were independent predictors of COVID-19 severity and mortality

Multi-ancestry genome-wide association meta-analysis of Parkinson's disease.

Although over 90 independent risk variants have been identified for Parkinson's disease using genome-wide association studies, most studies have been performed in just one population at a time. Here we performed a large-scale multi-ancestry meta-analysis of Parkinson's disease with 49,049 cases, 18,785 proxy cases and 2,458,063 controls including individuals of European, East Asian, Latin American and African ancestry. In a meta-analysis, we identified 78 independent genome-wide significant loci, including 12 potentially novel loci (MTF2, PIK3CA, ADD1, SYBU, IRS2, USP8, PIGL, FASN, MYLK2, USP25, EP300 and PPP6R2) and fine-mapped 6 putative causal variants at 6 known PD loci. By combining our results with publicly available eQTL data, we identified 25 putative risk genes in these novel loci whose expression is associated with PD risk. This work lays the groundwork for future efforts aimed at identifying PD loci in non-European populations