Contributors:Carmeline J. Dsilva, Ronen Talmon, Ronald R. Coifman, Ioannis G. Kevrekidis
Nonlinear manifold learning algorithms, such as diffusion maps, have been fruitfully applied in recent years to the analysis of large and complex data sets. However, such algorithms still encounter challenges when faced with real data. One such challenge is the existence of “repeated eigendirections,” which obscures the detection of the true dimensionality of the underlying manifold and arises when several embedding coordinates parametrize the same direction in the intrinsic geometry of the data set. We propose an algorithm, based on local linear regression, to automatically detect coordinates corresponding to repeated eigendirections. We construct a more parsimonious embedding using only the eigenvectors corresponding to unique eigendirections, and we show that this reduced diffusion maps embedding induces a metric which is equivalent to the standard diffusion distance. We first demonstrate the utility and flexibility of our approach on synthetic data sets. We then apply our algorithm to data collected from a stochastic model of cellular chemotaxis, where our approach for factoring out repeated eigendirections allows us to detect changes in dynamical behavior and the underlying intrinsic system dimensionality directly from data.
Contributors:Hong-di He, Chen-yan Zhang, Wei-li Wang, Yang-yang Hao, Yi Ding
In this paper, a coupled map car-following model is extended to two-lane traffic system. Based on it, the numerical simulations for one stop and series stops situations are performed respectively under the open boundary condition. The evolution of traffic jam and corresponding energy consumption are then explored and compared each other. Additionally, the influences of the lane changing rule and control scheme on traffic jam and energy consumption are investigated separately. The results show that lane changing rule and control scheme are found not only to suppress the traffic jam but also to reduce the energy consumption. The control scheme exhibit better behavior than lane changing rule does in suppressing traffic jam and reducing energy consumption in two-lane traffic system. The outputs of these findings demonstrate the potential of the proposed model to be applicable to evaluate the control schemes for suppressing traffic jam and reducing energy consumption in real traffic condition.
Given a many-to-one bi-modal transportation network where each origin is connected to the destination by a bottleneck-constrained highway and a parallel transit line, we investigate the parking permit management methods to minimize traffic time cost and traffic emission cost simultaneously. More importantly, the optimal supply of parking spots is also discussed in the policies of parking permit. First, we derive the total travel costs and emission costs for the two cases of sufficient and insufficient parking spot provisions at the destination. Second, we propose a bi-objective model and solve the Pareto optimal parking permit distribution, given a certain level of parking supply. Third, we investigate the optimal parking supply in the policy of parking permit distribution, with the objectives of minimizing both total travel cost and traffic emission. Fourth, we provide a model of optimizing parking supply, in the policy of free trading of parking permits. Finally, the numerical examples are presented to illustrate the effectiveness of these schemes, and the numerical results show that restricting parking supply at the city center could be efficient to reduce traffic emission.
Contributors:Rachel Wood, Federico Bernaldo de Quirós, José-Manuel Maíllo-Fernández, José-Miguel Tejero, Ana Neira, Thomas Higham
The majority of archaeological remains found at El Castillo in northern Iberia were excavated between 1910 and 1914 by Hugo Obermaier. Since the 1980s El Castillo has been studied through a detailed analysis of Obermaier's original excavation notes, the cleaning and study of the extant section, and the excavation of material in the shelter entrance. Radiocarbon dating of charcoal from the modern (1980s onwards) excavation suggested that unit 18, corresponding to Aurignacian Delta of the 1910s excavation, was significantly earlier than other Aurignacian assemblages in western Europe. Combined with a reanalysis of the lithic and osseous industry, these dates led to the suggestion that material in unit 18 and Aurignacian Delta was a transitional industry, showing a gradual transformation of the Mousterian into the Upper Palaeolithic. The conclusion has profound implications for understanding the appearance of the Upper Palaeolithic in western Europe. However, the theory has been heavily debated, with criticism focusing on the analysis of the lithic and bone assemblage as well as the chronology. We focus on the latter, and assess whether the original dates were accurate, whether they were well associated with the archaeology, and whether there was vertical and lateral variation in the age of the assemblages within unit 18 and Aurignacian Delta. New radiocarbon dates on humanly modified bone suggest that in the new area of excavation, unit 18 is found to be earlier than 42 cal kBP, with no evidence of material of a younger age. In contrast, in the old excavation area, Aurignacian Delta does include material of a younger age. This suggests that discussion of the Transitional Aurignacian can only include material from unit 18, in the new area of excavation.
Contributors:Gulzar Ahmad Nayik, Yogita Suhag, Ishrat Majid, Vikas Nanda
The study was intended to characterize three honeys (acacia, pine honeydew and multifloral) from high altitude Kashmir valley of India according to their macro minerals (K, Ca, Na and P), antioxidant properties and sugar parameters. The result for total phenolic content (22.68–59.84mg GAE/100g) and total flavonoid content (6.10–8.12mg QE/100g), revealed that honeys from Kashmir valley have high antioxidant activity. Principal component analysis (PCA), explained more than 81% of the variance. Four sugars were identified and quantified by HPLC, which include monosaccharides and disaccharides. Chemometric methods such as principal component analysis and linear discriminate techniques were applied on the data in order to differentiate the honeys. PCA explained more than 81% of the variance with the first two PC variables with minerals and antioxidant properties having highest discriminating power while LDA successfully classified all the unifloral honey samples.
The effect of autoclaving (120°C/30min), debranching (2% pullulanase/1h) and storage at 4°C (DS4) or 32°C (DS32) or 60°C (DS60) for 24h on starch fractions, functional, pasting, thermal and structural properties of sweet potato starch was investigated. Results showed that DS4 sample displayed the lower functional properties than other modified starches. Debranching showed a significant increase in the apparent amylose content of native starch from 18.56% to 25%. A higher yield of RS (28.76%) was observed in debranched starch stored at 4°C (DS4) due to the higher degree of retrogradation. All debranched starches showed a substantial decrease in pasting profile and higher gelatinization temperatures than in native starch. B+V X-ray diffraction pattern was observed in debranched starches with increased crystallinity value. The scanning electron micrographs of debranched starches showed rough plate-like surfaces with irregularly shaped structures were observed due to debranching and retrogradation during storage. The study concludes that a combination of autoclaving, debranching and subsequent storage at 4°C is best technique to produce a higher amount of resistant starch in the sweet potato starch.
Contributors:I. Fricke-Galindo, H. Jung-Cook, A. LLerena, M. López-López
Las reacciones adversas a medicamentos (RAM) son un problema de salud pública y una importante causa de morbimortalidad a nivel mundial. En el caso de los fármacos antiepilépticos (FAE), la presencia de RAM puede ser un impedimento para lograr el éxito terapéutico al dificultar la adherencia al tratamiento e impactar la calidad de vida del paciente. La farmacogenética busca la identificación de variantes genéticas asociadas a la seguridad de los fármacos. En este artículo se revisan los genes que codifican para enzimas metabolizadoras y transportadores de fármacos, así como en el sistema HLA asociados a RAM inducidas por FAE.
Contributors:R. Vijayaragavan, S. Mullainathan, P. Ambalavanan, S. Nithiyanantham
Waste recovery is very important for public health and from environmental and industrial perspectives. The use of waste as useful raw material is strongly recommended, since it reduces the negative environmental impact associated with landfill and preserves non-renewable nature. This paper describes the usability of rock residue powder as an additive raw material in ceramic product. In the present study, qualitative analysis was carried out to determine the major and minor constituent minerals present in ceramic bodies made from rock residue powder by X-ray diffraction and FT-IR spectroscopic techniques. Also to study the mineralogical and physico-mechanical characterization of ceramic bodies made from rock residue powder. The present study demonstrates the usefulness of the physico-mechanical properties and spectroscopic techniques in determining the quality of the ceramic samples made from 10–50wt.% of rock residue additives.
Contributors:Luke M. Healy, Marie-Christine Guiot, Amit Bar-Or, So-Yoon Won, Gabrielle Perron, Craig Moore, Vijayaraghava T.S. Rao, Jack P. Antel
This study examines the transcriptional profiles of human adult brain-derived microglia in response to in vitro activating conditions previously used to polarize systemic myeloid cells into M1 and M2 phenotypes. A comparative study is done with monocyte-derived macrophages (MDMs), a myeloid cell type that also participates in disease relevant tissue injury and repair processes in the CNS. Current markers used to distinguish microglia and MDMs have been defined under homeostatic conditions. We observe that gene expression profiles of M1 microglia and MDMs overlap with an overrepresentation of immune-related pathways. M2 microglia and MDMs have distinct transcriptional signatures. Upregulated genes in M2 microglia favor neural-related pathways whereas upregulated genes in M2 MDMs are mostly involved in antigen presentation. Our microarray screen identifies candidate molecules that can potentially distinguish microglia and MDMs under all activation conditions. To be determined is how our observations made using conventional in vitro polarization translate into cellular responses to the complex combination of signals encountered in neurologic disease states.