We constructed a corpus of digitized texts containing about 4% of all books ever printed. Analysis of this corpus enables us to investigate cultural trends quantitatively. We survey the vast terrain of ‘culturomics’, focusing on linguistic and cultural phenomena that were reflected in the English language between 1800 and 2000. We show how this approach can provide insights about fields as diverse as lexicography, the evolution of grammar, collective memory, the adoption of technology, the pursuit of fame, censorship, and historical epidemiology. ‘Culturomics’ extends the boundaries of rigorous quantitative inquiry to a wide array of new phenomena spanning the social sciences and the humanities.

Understanding the mechanisms of efficient and robust energy transfer in light-harvesting systems provides new insights for the optimal design of artificial systems. In this paper, we use the Fenna-Matthews-Olson (FMO) protein complex and phycocyanin 645 (PC 645) to explore the general dependence on physical parameters that help maximize the efficiency and maintain its stability. With the Haken-Strobl model, the maximal energy transfer efficiency (ETE) is achieved under an intermediate optimal value of dephasing rate. To avoid the infinite temperature assumption in the Haken-Strobl model and the failure of the Redfield equation in predicting the Forster rate behavior, we use the generalized Bloch-Redfield (GBR) equation approach to correctly describe dissipative exciton dynamics and find that maximal ETE can be achieved under various physical conditions, including temperature, reorganization energy, and spatial-temporal correlations in noise. We also identify regimes of reorganization energy where the ETE changes monotonically with temperature or spatial correlation and therefore cannot be optimized with respect to these two variables.Photosynthetic processes in plants, bacteria and marine algae provide key insights into designing artificial light harvesting systems that operate efficiently and robustly [1, 2]. The initial stages in the conversion of solar energy into chemical and other useful forms of energy for human consumption can be described by exciton dynamics with trapping and dissipation [3,4]. Recent experimental and computational studies suggest that environmental noise can assist exciton transport and can be optimized for maximal energy transfer efficiency (ETE) [5]- [20]. Quantum entanglement in photosynthetic light-harvesting complexes has also been studied with the consideration of environmental noise [21]. In this paper, using two light-harvesting systems, FMO and PC 645, we examine the optimization of the ETE, with respect to reorganization energy, temperature, and spatial-temporal correlations.This paper closely follows the theoretical formulation presented in a recent review [17] and further examines issues relevant for realistic light-harvesting systems. The review article addresses two questions: basic mechanisms of optimal energy transfer and systematic mapping to kinetic networks. Since environmental noise helps maximize energy transfer efficiency, it stands to reason that light-harvesting systems can be optimized to achieve best performance under a given environment, which leads to the proposal of optimal design. Previous work on simple models [10,17] and FMO [13]-[16] use the Haken-Strobl model, an infinite temperature model, and therefore report optimization a function of single parameter, the pure dephasing rate.It remains an open question if the ETE can be optimized as a function of temperature, reorganization energy, bath correlation time, and spatial correlation. In this paper, we will further examine the idea of noise-enhanced optimal energy transfer with explicit considerations of d...

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Traditionally, large quantities of ceramic fillers are added to polymers in order to obtain high thermally conductive polymer composites, which are used for electronic encapsulants. However, that is not cost effective enough. In this study, Si3N4 particle filled epoxy composite with a novel structure was fabricated by a processing method and structure design. Epoxy resin used in particle form was obtained by premixing and crushing. Different particle sizes were selected by sieving. High thermal conductivity was achieved at relative low volume fraction of the filler. The microstructure of the composites indicates that a continuous network is formed by the filler, which mainly completes the heat conduction. Thermal conductivity of the composites increases as the filler content increases, and the samples exhibit a highest thermal conductivity of 1.8W∕mK at 30% volume fraction of the filler in the composites using epoxy particles of 2mm. The composites show low dielectric constant and low dielectric loss.

The epoxy molding compound (EMC) with thermal conductive pathways was developed by structure designing. Three kinds of EMCs with different thermal conductivities were used in this investigation, specifically epoxy filled with Si 3 N 4 , filled with hybrid Si 3 N 4 /SiO 2 , and filled with SiO 2 . Improved thermal conductivity was achieved by constructing thermal conductive pathways using high thermal conductivity EMC (Si 3 N 4 ) in low thermal conductivity EMC (SiO 2 ). The morphology and microstructure of the top of EMC indicate that continuous network is formed by the filler which anticipates heat conductivity. The highest thermal conductivity of the EMC was 2.5 W/m K, reached when the volume fraction of EMC (Si 3 N 4 ) is 80% (to compare with hybrid Si 3 N 4 /SiO 2 filled-EMC, the content of total fillers in the EMC was kept at 60 vol %). For a given volume fraction of EMC (Si 3 N 4 ) in the EMC system, thermal conductivity values increase according to the order EMC (Si 3 N 4 ) particles filled-EMC, hybrid Si 3 N 4 /SiO 2 filled-EMC, and EMC(SiO 2 ) particles filled-EMC. The coefficient of thermal expansion (CTE) decreases with increasing Si 3 N 4 content in the whole filler. The values of CTE ranged between 23 Â 10 À6 and 30 Â 10 À6 K À1. The investigated EMC samples have a flexural strength of about 36-39 MPa. The dielectric constant increases with Si 3 N 4 content but generally remains at a low level (<6, at 1 MHz). The average electrical volume resistivity of the EMC samples are higher than 1.4 Â 10 10 X m, the average electrical surface resistivity of the EMC samples are higher than 6.7 Â 10 14 X.

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