Light trapping in ultrathin plasmonic solar cells

We report on the design, fabrication, and measurement of ultrathin film a-Si:H solar cells with nanostructured plasmonic back contacts, which demonstrate enhanced short circuit current densities compared to cells having flat or randomly textured back contacts. The primary photocurrent enhancement occurs in the spectral range from 550 nm to 800 nm. We use angle-resolved photocurrent spectroscopy to confirm that the enhanced absorption is due to coupling to guided modes supported by the cell. Full-field electromagnetic simulation of the absorption in the active a-Si:H layer agrees well with the experimental results. Furthermore, the nanopatterns were fabricated via an inexpensive, scalable, and precise nanopatterning method. These results should guide design of optimized, non-random nanostructured back reflectors for thin film solar cells

Processes and products of turbidity currents entering soft muddy substrates

New laboratory experiments reveal that cohesionless turbidity currents are able to enter cohesive soft muddy substrates without losing their shape. These intrabed currents are driven by bed shear stress exceeding bed cohesive strength, and by flow density exceeding bed den - sity. The flows produce unique turbidites with internal mud layers, mixed cohesive-nonco - hesive sediment layers, and flame and load structures. A depositional model for intrabed (I) turbidites is proposed, comprising, from base to top: I1�sand-bearing mud, with a scoured base, dispersed mud, and mud clasts; I2�muddy sand from the intrabed portion of the tur - bidity current; I3�sandy mud with a speckled appearance; and I4�mud-poor sand from the suprabed portion of the flow. Complete I1�I4 turbidites are inferred to dominate loca - tions in nature where the currents mix with the bed and deep erosional scours form, filled with deformed or chaotic sand-mud mixtures. Further downflow, base-missing I2�I4 and I4 sequences signify gradual deceleration, loss of erosivity, and termination of intrabed flo

Understanding communicative actions:A repetitive TMS study

Previous work has shown that the right posterior superior temporal sulcus (RpSTS) is involved in inferring both instrumental goals and communicative intentions of observed actions (1, 2), using previous knowledge to generate perceptual and/or conceptual inferences (3, 4). Here, we disturb neural activity in RpSTS to test whether this region is necessary for understanding the meaning of novel communicative actions. Thirteen subjects received two 20 min sessions of low-frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS), either over RpSTS (50,-42,14) or over a control region (area MT+, -43,-70,10), before performance of a communicative game and a control task. The game involved controlled non-verbal communicative interactions between pairs of subjects (40 trials). Each pair was asked to jointly create a goal configuration of two geometrical tokens, using the movements of the tokens on a gameboard as the only available communicative channel (5). One participant (a confederate) knew the goal configuration, and she moved her token on the gameboard to inform an addressee (a participant) where and how to position his token. The control task was a visual search paradigm that involved the same stimuli, responses, joint attention, and inter-subjects dependencies, but no communicative necessities. Performance was indexed by Task Efficiency, defined as the number of correct responses per unit of planning time, and by Efficiency Rate, defined as the rate of change (across trials) in Task Efficiency. After rTMS over RpSTS, but not left MT+, the Efficiency Rate of the addresses was reduced in the communicative game, but not in the visual search. In contrast, after rTMS over left MT+, subjects were not able to benefit from experience gained during the previous trials of the visual search task (Task X Site interaction, p<0.05). There were no corresponding interactions between tasks and site of rTMS intervention on the Task Efficiency parameter. These findings qualify how RpSTS contributes to understanding the meaning of non-verbal communicative actions. Repetitive TMS over RpSTS did not disrupt the ability of addressees to interpret novel communicative actions. Rather, this region appears to be necessary for incorporating previous knowledge, accumulated during interactions with a communicative partner, to constrain the inferential process that leads to action understanding

Children’s route choice during active transportation to school: difference between shortest and actual route

BackgroundThe purpose of this study is to increase our understanding of environmental correlates that are associated with route choice during active transportation to school (ATS) by comparing characteristics of actual walking and cycling routes between home and school with the shortest possible route to school.MethodsChildren (n = 184; 86 boys, 98 girls; age range: 8–12 years) from seven schools in suburban municipalities in the Netherlands participated in the study. Actual walking and cycling routes to school were measured with a GPS-device that children wore during an entire school week. Measurements were conducted in the period April–June 2014. Route characteristics for both actual and shortest routes between home and school were determined for a buffer of 25m from the routes and divided into four categories: Land use (residential, commercial, recreational, traffic areas), Aesthetics (presence of greenery/natural water ways along route), Traffic (safety measures such as traffic lights, zebra crossings, speed bumps) and Type of street (pedestrian, cycling, residential streets, arterial roads). Comparison of characteristics of shortest and actual routes was performed with conditional logistic regression models.ResultsMedian distance of the actual walking routes was 390.1m, whereas median distance of actual cycling routes was 673.9m. Actual walking and cycling routes were not significantly longer than the shortest possible routes. Children mainly traveled through residential areas on their way to school (>80% of the route). Traffic lights were found to be positively associated with route choice during ATS. Zebra crossings were less often present along the actual routes (walking: OR = 0.17, 95 % CI = 0.05–0.58; cycling: OR = 0.31, 95 % CI = 0.14–0.67), and streets with a high occurrence of accidents were less often used during cycling to school (OR = 0.57, 95% CI = 0.43–0.76). Moreover, percentage of visible surface water along the actual route was higher compared to the shortest routes (walking: OR = 1.04, 95 % CI = 1.01–1.07; cycling: OR = 1.03, 95 % CI = 1.01–1.05).DiscussionThis study showed a novel approach to examine built environmental exposure during active transport to school. Most of the results of the study suggest that children avoid to walk or cycle along busy roads on their way to school.Electronic supplementary materialThe online version of this article (doi:10.1186/s12966-016-0373-y) contains supplementary material, which is available to authorized users

The efficacy of itraconazole against systemic fungal infections in neutropenic patients : a randomised comparative study with amphotericin B

Contains fulltext : 4533.pdf (publisher's version ) (Open Access

Dutch guidelines on care for extremely premature infants:Navigating between personalisation and standardization

OBJECTIVE: There is no international consensus on what type of guideline is preferred for care at the limit of viability. We aimed to conceptualize what type of guideline is preferred by Dutch healthcare professionals: 1) none; 2) gestational-age-based; 3) gestational-age-based-plus; or 4) prognosis-based via a survey instrument. Additional questions were asked to explore the grey zone and attitudes towards treatment variation. FINDING: 769 surveys were received. Most of the respondents (72.8%) preferred a gestational-age-based-plus guideline. Around 50% preferred 24+0/7 weeks gestational age as the lower limit of the grey zone, whereas 26+0/7 weeks was the most preferred upper limit. Professionals considered treatment variation acceptable when it is based upon parental values, but unacceptable when it is based upon the hospital's policy or the physician's opinion. CONCLUSION: In contrast to the current Dutch guideline, our results suggest that there is a preference to take into account individual factors besides gestational age