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Abstract In this paper we study the effect of absorption peak correlation in finite length carbon nanotubes and graphene nanoribbons. It is shown, in the orthogonal π-orbital tight-binding model with the nearest neighbor approximation, that if the ribbon width is a half of the tube circumference the effect takes place for all achiral ribbons (zigzag, armchair and bearded), and corresponding tubes, starting from lengths of about 30 nm. This correlation should be useful in designing nanoribbon-based optoelectronics devices fully integrated into a single layer of graphene. [ABSTRACT FROM AUTHOR]

Developing means to reduce the cost of solar energy is vital to curb our carbon footprint over the upcoming decades. A luminescent solar concentrator (LSC) is a potential solution as it provides light concentration without any tracking device and can be readily integrated into the built environment. In this study we report on an advanced LSC design that employs quantum dots as absorption fluorophores and organic dye molecules as emission fluorophores. By linking the two types of fluorophores to each other, energy is transferred efficiently via Förster resonance energy transfer (FRET) from the quantum dot to the dye molecule. This novel method makes use of the quantum dot's spectrally wide absorption profile and the higher quantum yield of the dye. We show that our design can overcome the losses normally incurred due to a low quantum yield emitter by transferring the absorbed energy to a linked fluorophore with a higher quantum yield. Our experimental measurements show FRET can enhance the optical efficiency of a LSC by at least 24.7%. The maximum theoretical efficiency has been investigated by ray-tracing and has been found to be 75.1%; this represents a relative improvement of even 215.5% compared to a LSC doped with quantum dots only (23.8%), showing the great potential of our concept. Our design will initiate interest in fluorophores which have not been considered for LSC applications thus far because of their low quantum yield or small Stokes shift. [ABSTRACT FROM AUTHOR]

Objectives: The primary objective of our study was to examine the safety and the secondary objective was to examine the effectiveness of ginger for nausea and vomiting of pregnancy (NVP).Study Design: Pregnant women who called the Motherisk Program who were taking ginger during the first trimester of pregnancy were enrolled in the study. The women were compared with a group of women who were exposed to nonteratogenic drugs that were not antiemetic medications. The women were followed up to ascertain the outcome of the pregnancy and the health of their infants. They were also asked on a scale of 0 to 10 how effective the ginger was for their symptoms of NVP.Results: We were able to ascertain the outcome of 187 pregnancies. There were 181 live births, 2 stillbirths, 3 spontaneous abortions, and 1 therapeutic abortion. The mean birth weight was 3542+/-543 g, the mean gestational age was 39+/-2 weeks, and there were three major malformations. There were no statistical differences in the outcomes between the ginger group and the comparison group with the exception of more infants weighing less than 2500 g in the comparison group (12 vs 3, P < or =.001). There were a total of 66 completed effectiveness scores with the mean score of 3.3+/-2.9 SD.Conclusion: These results suggest that ginger does not appear to increase the rates of major malformations above the baseline rate of 1% to 3% and that it has a mild effect in the treatment of NVP. [ABSTRACT FROM AUTHOR]

Abstract: The Quake-Catcher Network (QCN) project uses the low-cost sensors, i.e., accelerometers at- tached to volunteers’ computers, to detect earthquakes. The master-worker topology currently used in QCN and other similar projects suffers from major weaknesses. The centralized master can fail to collect data if the volunteers’ computers cannot connect to the network, or it can introduce significant delays in the warning if the network is congested. We propose to solve these problems by using multiple servers in a more advanced network topology than the simple master-worker configuration. We first consider several critical scenarios in which the current master-worker configuration can hinder the early warning of an earthquake, and then integrate the advanced network topology around multiple servers and emulate these critical scenarios in a simulation environment to quantify the benefits and costs of our proposed solution. By using metrics of interest that have a clear scientific meaning for the scope of the QCN project, we show how our solution can reduce the time to detect an earthquake from 1.8 s to 173ms in case of network congestion and the number of lost trickle messages from 2,013 to 391 messages in case of network failure. [Copyright &y& Elsevier]

OBJECTIVES: The primary objective of our study was to examine the safety and the secondary objective was to examine the effectiveness of ginger for nausea and vomiting of pregnancy (NVP). STUDY DESIGN: Pregnant women who called the Motherisk Program who were taking ginger during the first trimester of pregnancy were enrolled in the study. The women were compared with a group of women who were exposed to nonteratogenic drugs that were not antiemetic medications. The women were followed up to ascertain the outcome of the pregnancy and the health of their infants. They were also asked on a scale of 0 to10 how effective the ginger was for their symptoms of NVP. RESULTS: We were able to ascertain the outcome of 187 pregnancies. There were 181 live births, 2 stillbirths, 3 spontaneous abortions, and 1 therapeutic abortion. The mean birth weight was 3542 ± 543 g, the mean gestational age was 39 ± 2 weeks, and there were three major malformations. There were no statistical differences in the outcomes between the ginger group and the comparison group with the exception of more infants weighing less than 2500 g in the comparison group (12 vs 3, P ≤ .001). There were a total of 66 completed effectiveness scores with the mean score of 3.3 ± 2.9 SD. CONCLUSION: These results suggest that ginger does not appear to increase the rates of major malformations above the baseline rate of 1% to 3% and that it has a mild effect in the treatment of NVP. [ABSTRACT FROM AUTHOR]

Luminescent Solar Concentrators (LSCs) have drawn huge interest recently as a technology to pave the way towards the seamless integration of photovoltaics to a range of high-value industries; from architecture and sports to leisure and consumer electronics. Additional device flexibility comes with the inherent ability to attain freeform shapes, expanding the possible fabrication methods, applications and retro-fitting techniques. Unfortunately, flexible LSCs suffer from curvature induced losses which can severely reduce their efficiency, inhibiting the potential of large-scale devices. In this work, we experimentally demonstrate an all-silicone based flexible LSC and Distributed Bragg Reflector (DBR) combination diminishing curvature induced losses. The DBRs, fabricated using scalable solution-based processes, exhibit optical properties precisely engineered to partner our LSCs, as well as high uniformity, resistance to temperature and curvature. Comprehensive modelling shows that for large-scale devices (1 m2) we can essentially decouple the performance of the LSC from curvature, steering the technology towards commercial viability. Image 1 • We have demonstrated an all-flexible LSC and Distributed Bragg Reflector combination, allowing for efficient freeform LSCs. • Both LSC and DBR consist entirely of silicone-based materials, giving homogeneity, compatibility and mechanical consistency throughout. • We use a scalable, single-pot method to fabricate our DBRs and exhibit excellent control of optical properties of our multilayer structures. • We show a significant reduction of the dependence of the device efficiency on curvature. • We analyse the performance of large-scale LSCs using Monte-Carlo statistical models demonstrating a clear pathway to real consumer products. [ABSTRACT FROM AUTHOR]

To follow the visual acuity development of children exposed to or infected with the Zika virus (ZIKV) during gestation and to relate potential visual acuity deficits to their clinical condition. In this prospective study, visual acuity was measured via Teller Acuity Cards in three groups of children: (1) those with confirmed ZIKV exposure (ZE) through the mother only, (2) those with confirmed infection (ZI), and (3) unaffected controls. Visual acuity was measured 2-4 times in each child during the first 30 months of age. The study included 22 children in the ZE group, 11 in the ZI group, and 27 controls. Visual acuity developed normally in both patient groups, including infected patients (ZI) that did not manifest clinical symptoms. In a small subgroup of patients with characteristics consistent with congenital Zika syndrome (CZS), visual acuity was within normative values, with the exception of single child with chorioretinal atrophy. In this southeastern Brazil study cohort, visual acuity development seemed to progress normally in infected children without CZS symptoms. [ABSTRACT FROM AUTHOR]

To evaluate visual acuity and visual acuity development in children from the state of São Paulo, Brazil, who were exposed to the Zika virus (ZIKV) gestationally. Children who had been exposed to ZIKV during gestation and age-matched control subjects received visual acuity and funduscopic examination. ZIKV exposure was confirmed by maternal quantitative polymerase chain reaction testing or serology assay. The ZIKV group was divided into two subgroups: exposed (ZE), with only the mother having confirmed ZIKV infection, and infected (ZI), with confirmed infection. Visual acuity development was compared with prior norms and quantified by measuring visual acuity correlation with age. A total of 110 children were included: 47 who had been exposed to ZIKV (ZE, 23; ZI, 24) and 63 controls. Abnormal visual acuity was found in 5 of 24 ZI children. Of the 4 children with microcephaly, only 2 had visual acuity loss (only 1 also had abnormal funduscopic findings). There was significant correlation between age and visual acuity in both the control group (R 2 = 0.8; P < 0.0000) and the ZE subgroup (R 2 = 0.6; P < 0.0000). However, visual acuity did not correlate with age in the ZI subgroup (R 2 = 0.04; P = 0.38). Furthermore, the increment in octaves/month was much lower in the ZI subgroup. Our data indicate that visual acuity losses only occur in infants who suffered gestational-infection, not simply exposure. Lack of correlation between age and visual acuity in the ZI subgroup suggests a slowing of visual development even in the absence of microcephaly. This result may have broad implications for the deleterious effects of ZIKV on the central nervous system. [ABSTRACT FROM AUTHOR]