Dielectric ground plane design over bianisotropic media

In this contribution we show how it is possible to construct a new multilayer dielectric ground plane using bianisotropic media that is highly reflective over a broad range of wavelengths at all angles. This omnidirectional dielectric reflector-unlike metal-is nearly totally lossless and can be engineered to have extremely high reflectivity. The plane wave solution is then used to study in a rigorous way the wave equations satisfied by the electromagnetic field in a layered structure filled with such a material. Numerical results are also presented as a function of the material parameters in order to demonstrate the features of this approach.     

Broadband light trapping with disordered photonic structures in thin‐film silicon solar cells

We theoretically investigate light trapping with disordered 1D photonic structures in thin‐film crystalline silicon solar cells. The disorder is modelled in a finite‐size supercell, which allows the use of rigorous coupled‐wave analysis to calculate the optical properties of the devices and the short‐circuit current density J_sc. The role of the Fourier transform of the photonic pattern in the light trapping is investigated, and the optimal correlation between size and position disorder is found. This result is used to optimize the disorder in a more effective way, using a single parameter. We find that a Gaussian disorder always enhances the device performance with respect to the best ordered configuration. To properly quantify this improvement, we calculate the Lambertian limit to the absorption enhancement for 1D photonic structures in crystalline silicon, following the previous work for the 2D case [M.A. Green, Progr. Photovolt: Res. Appl. 2002; 10 (4), pp. 235–241]. We find that disorder optimization can give a relevant contribution to approach this limit. Finally, we propose an optimal disordered 2D configuration and estimate the maximum short‐circuit current that can be achieved, potentially leading to efficiencies that are comparable with the values of other thin‐film solar cell technologies. Copyright © 2013 John Wiley & Sons, Ltd.     

Probing small network differences in sulfur‐cured rubber compounds by combining nuclear magnetic resonance and swelling methods

We studied the network structure of elastomers based on polyisoprene, polybutadiene, and their blends in the narrow range of formulations compatible with actual use in the automotive tyre industry. Cross‐link density (CLD) was quantified comparatively by low‐field ¹H multiple quantum time domain nuclear magnetic resonance (MQ TD‐NMR) and by equilibrium swelling technique. The robustness and agreement of the two methods was demonstrated in measuring minute alterations of unfilled vulcanizates beyond the optimum cure time. Comparison with samples where polysulfidic bonds were selectively cleaved also demonstrates that the length of the sulfur chain constituting the cross‐link does not significantly affect residual dipolar coupling. Kraus, Lorenz, and Parks correction for filler restriction on swelling is validated by MQ TD‐NMR, which also allows extracting information on cross‐link distribution not provided by swelling measurement. Cross‐link distributions in the blends were demonstrated to be significantly different from the weighted average of the pure samples, while average proton–proton residual dipolar coupling values correspond. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42700.     

Provenance studies of obsidians from Neolithic contexts in Southern Italy by IBA (Ion Beam Analysis) methods

Obsidian samples recovered in archaeological contexts in Southern Italy were analysed by PIXE (Particle Induced X-ray Emission) and PIGE (Particle Induced Gamma Ray Emission) for the quantitative determination of both major and trace elements composition. The archaeological contexts were absolutely dated to the 5th millennium BC by mean of AMS (Accelerator Mass Spectrometry) radiocarbon dating analyses carried out on associated organic materials such as charcoal and human bones. The comparison of the compositional results obtained for the analysed samples with published data available for the known obsidian sources in the Mediterranean allowed to identify the sources of the raw material, giving an important contribution to the reconstruction of the ancient trade and exchange routes in Southern Italy prehistory.     

Heterogeneous Off-Target Effects of Ultra-Low Dose Dimethyl Sulfoxide (DMSO) on Targetable Signaling Events in Lung Cancer In Vitro Models

Targetable alterations in cancer offer novel opportunities to the drug discovery process. However, pre-clinical testing often requires solubilization of these drugs in cosolvents like dimethyl sulfoxide (DMSO). Using a panel of cell lines commonly used for in vitro drug screening and pre-clinical testing, we explored the DMSO off-target effects on functional signaling networks, drug targets, and downstream substrates. Eight Non-Small Cell Lung Cancer (NSCLC) cell lines were incubated with three concentrations of DMSO (0.0008%, 0.002%, and 0.004% v/v) over time. Expression and activation levels of 187 proteins, of which 137 were kinases and downstream substrates, were captured using the Reverse Phase Protein Array (RPPA). The DMSO effect was heterogeneous across cell lines and varied based on concentration, exposure time, and cell line. Of the 187 proteins measured, all were statistically different in at least one comparison at the highest DMSO concentration, followed by 99.5% and 98.9% at lower concentrations. Only 46% of the proteins were found to be statistically different in more than 5 cell lines, indicating heterogeneous response across models. These cell line specific alterations modulate response to in vitro drug screening. Ultra-low DMSO concentrations have broad and heterogeneous effects on targetable signaling proteins. Off-target effects need to be carefully evaluated in pre-clinical drug screening and testing.     

《建筑能效实时活动识别》

居住建筑和商业建筑的电耗过半用于采光和电器设备。这些系统的耗电直接与使用者行为活动有关。通过识别活动与确认相关可能的节能要点,可研发更多的有效策略从而设计更好的建筑和自动化系统。根据这一目的,采用归纳推理方法,引入一个框架来检测居民活动和潜在能耗浪费问题,以及可以实时转换到非高峰时段的高峰时段耗能情况。框架由三个子算法组成,用于行为检测、活动识别和浪费预估。作为实时输入,动作检测算法从传感系统接收数据,该传感系统由插头式计量器和传感器组成,以通过无监督聚类模型检测发生的动作(例如打开电器)。被检测的活动随后通过对构建本体的语义推理用于了活动识别算法。基于公认的活动,浪费估算算法可识别潜在浪费行为,并估算出节能潜力。为了评估本文设计的框架的性能,对1个5人办公室和2个单人住房进行了为期两周的实验研究。实验之后,采用了用于动作和活动的地面实况标签,评估了动作检测和动作识别算法的性能。采用了主成分分析法的高斯混合模型,对动作检测的平均准确率达97.6%,对活动识别的平均准确率为96.7%。此外,平均电器或照明系统消费的35.5%的电被认为是潜在的节约项。