678 research outputs found
On the relationship between travel time and travel distance of commuters. Reported versus network travel data in the Netherlands
This paper gives a detailed empirical analysis of the relationships between different indicators of costs of commuting trips by car: difference as the crow flies, shortest travel time according to route planner, corresponding travel distance, and reported travel time. Reported travel times are usually rounded in multiples of five minutes. This calls for special statistical techniques. Ignoring the phenomenon of rounding leads to biased estimation results for shorter distances. Rather surprisingly, the distance as the crow flies and the network distance appear to be slightly better proxies of the reported travel time compared with the shortest network travel time as indicated by the route planner. We conclude that where actual driving times are missing in commuting research the other three indicators mentioned may be used as proxies, but that the following problems may emerge: actual travel times may be considerably higher than network times generated by route planners, and the average speed of trips increases considerably with distance, implying an overestimate of travel time for long distance commuters. The only personal feature that contributes significantly to variations in reported travel times is gender: women appear to drive at lower average speeds according to our data. As indicated in the paper this may be explained by the differences in the car types of male and female drivers (females drive older and smaller cars) as well as higher numbers of stops/trip chaining among women. A concise analysis is carried out for carpoolers. Car-pooling leads to an increase in travel time of some 17% compared with solo drivers covering the same distance. In the case of car poolers, the above mentioned measures appear to be very poor proxies for the actual commuting times
Turning a Blind Eye? Punishment of Friends and Unfamiliar Peers After Observed Exclusion in Adolescence
In order to decrease the occurrence of social exclusion in adolescence, we need to better understand how adolescents perceive and behave toward peers involved in exclusion. We examined the role of friendships in treatment of perpetrators and victims of social exclusion. Eightyânine participants (aged 9â16) observed exclusion of an unfamiliar peer (victim) by their best friend and another unfamiliar peer. Subsequently, participants could give up valuable coins to altruistically punish or help peers. Results showed that participants altruistically compensated victims and punished unfamiliar excluders, but refrained from punishing their friends. Our findings show that friendship with excluders modulates altruistic punishment of peers and provide mechanistic insight into how friendships may influence treatment of peers involved in social exclusion during adolescence.Pathways through Adolescenc
Interruption of visually perceived forward motion in depth evokes a cortical activation shift from spatial to intentional motor regions
Forward locomotion generates a radially expanding flow of visual motion which supports goal-directed walking. In stationary mode, wide-field visual presentation of optic flow stimuli evokes the illusion of forward self-motion. These effects illustrate an intimate relation between visual and motor processing. In the present fMRI study, we applied optic flow to identify distinct interfaces between circuitries implicated in vision and movement. The dorsal premotor cortex (PMd) was expected to contribute to wide-field forward motion flow (FFw), reflecting a pathway for externally triggered motor control. Medial prefrontal activation was expected to follow interrupted optic flow urging internally generated action. Data of 15 healthy subjects were analyzed with Statistical Parametric Mapping and confirmed this hypothesis. Right PMd activation was seen in FFw, together with activations of posterior parietal cortex, ventral V5, and the right fusiform gyms. Conjunction analysis of the transition from wide to narrow forward flow and reversed wide-field flow revealed selective dorsal medial prefrontal activation. These findings point at equivalent visuomotor transformations in locomotion and goal-directed hand movement, in which parietal-premotor circuitry is crucially implicated. Possible implications of an activation shift from spatial to intentional motor regions for understanding freezing of gait in Parkinson's disease are discussed: impaired medial prefrontal function in Parkinson's disease may reflect an insufficient internal motor drive when visual support from optic flow is reduced at the entrance of a narrow corridor. (C) 2010 Elsevier B.V. All rights reserved
Stop sanitizing project management education: Embracing Desirable Difficulties to enhance practice-relevant online learning
By resisting the temptation to âsanitizeâ project management education, we show how embracing unpredictability and authenticity can enhance learning. In response to COVID-19 restrictions, we moved an interactive role-play online and explored the resultant learning through analysis of student performance and studentsâ individual reflections. Findings suggest that the online role-play boosted learning by exposing students to a challenging environment, which included tasks that stretched their capabilities and thus enhanced the level of âDesirable Difficultiesâ. Drawing on the concepts of Desirable Difficulties and ârole-play-as-rehearsalâ, we discuss the benefits of formative âtestingâ and propose a new concept: ârole-play-as-testingâ. Additionally, benefits to learning were attributed to the online setting, which reflects the increasing virtualization of practice. We hope to inspire other educators to embrace Desirable Difficulties and resist the temptation to sanitize project management education to create opportunities for future project leaders to test their learning in authentic settings
Opto-mechanical probe for combining atomic force microscopy and optical near-field surface analysis
We have developed a new easy-to-use probe that can be used to combine atomic force microscopy (AFM) and scanning near-field optical microscopy (SNOM). We show that, using this device, the evanescent field, obtained by total internal reflection conditions in a prism, can be visualized by approaching the surface with the scanning tip. Furthermore, we were able to obtain simultaneous AFM and SNOM images of a standard test grating in air and in liquid. The lateral resolution in AFM and SNOM mode was estimated to be 45 and 160 nm, respectively. This new probe overcomes a number of limitations that commercial probes have, while yielding the same resolution. (C) 2014 Optical Society of Americ
Susceptibility weighted imaging in intracranial hemorrhage:not all bleeds are black
To correctly recognize intracranial hemorrhage (ICH) and differentiate it from other lesions, knowledge of the imaging characteristics of an ICH on Susceptibility Weighted Imaging (SWI) is essential. It is a common misconception that blood is always black on SWI, and it is important to realize that hemorrhage has a variable appearance in different stages on SWI. Furthermore, the presence of a low signal on SWI does not equal the presence of blood products. In this review the appearance of ICH on SWI during all its stages and common other causes of a low signal on SWI are further discussed and illustrated.</p
Neural correlates of prosocial peer influence on public goods game donations during adolescence
A unique feature of adolescent social re-orientation is heightened sensitivity to peer influence when taking risks. However, positive peer influence effects are not yet well understood. The present fMRI study tested a novel hypothesis, by examining neural correlates of prosocial peer influence on donation decisions in adolescence. Participants (age 12â16 years; N Âź 61) made decisions in anonymous groups about the allocation of tokens between themselves and the group in a public goods game. Two spectator groups of same-age peersâin fact youth actorsâwere allegedly online during some of the decisions.The task had a within-subjects design with three conditions: (1) Evaluation: spectators evaluated decisions with likes for large donations to the group, (2) Spectator: spectators were present but no evaluative feedback was displayed and (3) Alone: no spectators nor feedback. Results showed that prosocial behavior increased in the presence of peers, and even more when participants received evaluative feedback from peers. Peer presence resulted in enhanced activity in several social brain regions including medial prefrontal cortex, temporal parietal junction (TPJ), precuneus and superior temporal sulcus.TPJ activity correlated with donations, which suggests similar networks for prosocial behavior and sensitivity to peers.These findings highlight the importance of peers in fostering prosocial development throughout adolescence.Social decision makin
Incidental findings during the diagnostic work-up in the head and neck cancer pathway:Effects on treatment delay and survival
Objectives: As a result of the increasing number of diagnostic scans, incidental findings (IFs) are more frequently encountered during oncological work-up in patients with head and neck squamous cell carcinomas (HNSCC). IFs are unintentional discoveries found on diagnostic imaging. Relevant IFs implicate clinical consequences, resulting in delay in oncologic treatment initiation, which is associated with unfavorable outcomes. This study is the first to investigate the incidence and nature of IFs over the years and establish the effect of relevant IFs on delay. Material and methods: This retrospective study compared two time periods (2010 & ndash;2011 and 2016 & ndash;2017), described associations between relevant IFs and delay in carepathway interval (days between first visit and treatment initiation) and assessed the effect of relevant IFs on overall two-year survival. Results: In total, 592 patients were included. At least one IF was found in 61.5% of the patients, most frequently on chest-CT. In 128 patients (21.6%) a relevant IF was identified, resulting for the majority in radiologist recommendations (e.g. additional scanning). Presence of a relevant IF was an independent significant factor associated with delay in treatment initiation. The risk of dying was higher for patients with a relevant IF, although not significant in the multivariable model (HR: 1.46, p = 0.079). Conclusion: In diagnostic work-up for HNSCC patients, relevant IFs are frequently encountered. As the frequency of additional imaging rises over the years, the number of IFs increased simultaneously. These relevant IFs yield clinical implications and this study described that relevant IFs result in significant delay in treatment initiation
Texture Consumption Patterns of 8- to 12-Month-Old Infants: A Reflection of Typical Feeding Development
Purpose: The lack of age-appropriate expectations for the acquisition of feeding skills and consumption of textured food in early childhood inhibits early and accurate identification of developmental delay in feeding and pediatric feeding disorder. The objective of this study was to describe texture intake patterns in a cohort of typically developing infants between 8 and 12 months of age, with the aim of informing future research to establish targets for feeding skill acquisition. Method: Using cross-sectional methodology, we studied the presence of liquid and solid textures and drinking methods in the diet, consumption patterns by texture and drinking methods, and caloric intake by texture via caregiver questionnaire and 3-day dietary intake record in 63 healthy infants between 8 and 12 months of age. Descriptive statistics and a one-way analysis of variance were conducted to compare the effect of age on texture intake patterns. Results: Findings reveal rapid advancement of intake patterns for texture overall and for energy intake by texture between 8 and 12 months of age. Whereas liquids continue to provide a large proportion of total energy through this time, solids contribute an equal proportion of energy by 12 months of age. Conclusions: This study describes texture intake patterns in a cohort of typically developing infants between 8 and 12 months of age by examining the presence of texture and drinking methods, liquid and solid consumption patterns, and energy intake by texture. When applied to data from a future population sample, findings will provide a threshold for age expectations for typical and disordered feeding development to aid in the detection of developmental delay in feeding and pediatric feeding disorder
Copeptin does not accurately predict disease severity in imported malaria
<p>Abstract</p> <p>Background</p> <p>Copeptin has recently been identified to be a stable surrogate marker for the unstable hormone arginine vasopressin (AVP). Copeptin has been shown to correlate with disease severity in leptospirosis and bacterial sepsis. Hyponatraemia is common in severe imported malaria and dysregulation of AVP release has been hypothesized as an underlying pathophysiological mechanism. The aim of the present study was to evaluate the performance of copeptin as a predictor of disease severity in imported malaria.</p> <p>Methods</p> <p>Copeptin was measured in stored serum samples of 204 patients with imported malaria that were admitted to our Institute for Tropical Diseases in Rotterdam in the period 1999-2010. The occurrence of WHO defined severe malaria was the primary end-point. The diagnostic performance of copeptin was compared to that of previously evaluated biomarkers C-reactive protein, procalcitonin, lactate and sodium.</p> <p>Results</p> <p>Of the 204 patients (141 <it>Plasmodium falciparum</it>, 63 non-falciparum infection), 25 had severe malaria. The Area Under the ROC curve of copeptin for severe disease (0.66 [95% confidence interval 0.59-0.72]) was comparable to that of lactate, sodium and procalcitonin. C-reactive protein (0.84 [95% CI 0.79-0.89]) had a significantly better performance as a biomarker for severe malaria than the other biomarkers.</p> <p>Conclusions</p> <p>C-reactive protein but not copeptin was found to be an accurate predictor for disease severity in imported malaria. The applicability of copeptin as a marker for severe malaria in clinical practice is limited to exclusion of severe malaria.</p
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