Terahertz metamaterials on flexible polypropylene substrate

The final publication is available at Springer via http://dx.doi.org/10.1007/s11468-014-9724-1In this work, we present a metamaterial working at terahertz frequencies made over a flexible polypropylene sub-strate. The experimental measurements, in accordance with the numerical calculations, show the metamaterial reliance on the impinging electric field polarization. The structure s symmetry yields purely electrical resonant responses eliminating bianisotropy effects. The widely used bendable polypropylene polymer may promote the insertion of metamaterial-based structures with special electromagnetic response in a number of objects of our daily lives such as textiles, automotive components, and sensingThis work was supported by the Spanish MICINN under contracts CONSOLIDER EMET CSD2008-00066 and TEC2011-28664-C02-02 and by the Universitat Politecnica de Valencia under the program INNOVA 2011.Ortuño Molinero, R.; García Meca, C.; Martínez Abietar, AJ. (2014). 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Report on the BTAS 2016 Video Person Recognition Evaluation

© 2016 IEEE. This report presents results from the Video Person Recognition Evaluation held in conjunction with the 8th IEEE International Conference on Biometrics: Theory, Applications, and Systems (BTAS). Two experiments required algorithms to recognize people in videos from the Point-and-Shoot Face Recognition Challenge Problem (PaSC). The first consisted of videos from a tripod mounted high quality video camera. The second contained videos acquired from 5 different handheld video cameras. There were 1,401 videos in each experiment of 265 subjects. The subjects, the scenes, and the actions carried out by the people are the same in both experiments. An additional experiment required algorithms to recognize people in videos from the Video Database of Moving Faces and People (VDMFP). There were 958 videos in this experiment of 297 subjects. Four groups from around the world participated in the evaluation. The top verification rate for PaSC from this evaluation is 0.98 at a false accept rate of 0.01 - a remarkable advancement in performance from the competition held at FG 2015

Electronic stress tensor analysis of hydrogenated palladium clusters

We study the chemical bonds of small palladium clusters Pd_n (n=2-9) saturated by hydrogen atoms using electronic stress tensor. Our calculation includes bond orders which are recently proposed based on the stress tensor. It is shown that our bond orders can classify the different types of chemical bonds in those clusters. In particular, we discuss Pd-H bonds associated with the H atoms with high coordination numbers and the difference of H-H bonds in the different Pd clusters from viewpoint of the electronic stress tensor. The notion of "pseudo-spindle structure" is proposed as the region between two atoms where the largest eigenvalue of the electronic stress tensor is negative and corresponding eigenvectors forming a pattern which connects them.Comment: 22 pages, 13 figures, published online, Theoretical Chemistry Account

Modulation of Transmission Spectra of Anodized Alumina Membrane Distributed Bragg Reflector by Controlling Anodization Temperature

We have successfully prepared anodized alumina membrane distributed Bragg reflector (DBR) using electrochemical anodization method. The transmission peak of this distributed Bragg reflector could be easily and effectively modulated to cover almost any wavelength range of the whole visible spectrum by adjusting anodization temperature

The Ubiquitin Peptidase UCHL1 Induces G0/G1 Cell Cycle Arrest and Apoptosis Through Stabilizing p53 and Is Frequently Silenced in Breast Cancer

Background: Breast cancer (BrCa) is a complex disease driven by aberrant gene alterations and environmental factors. Recent studies reveal that abnormal epigenetic gene regulation also plays an important role in its pathogenesis. Ubiquitin carboxyl- terminal esterase L1 (UCHL1) is a tumor suppressor silenced by promoter methylation in multiple cancers, but its role and alterations in breast tumorigenesis remain unclear. Methodology/Principal Findings: We found that UCHL1 was frequently downregulated or silenced in breast cancer cell lines and tumor tissues, but readily expressed in normal breast tissues and mammary epithelial cells. Promoter methylation of UCHL1 was detected in 9 of 10 breast cancer cell lines (90%) and 53 of 66 (80%) primary tumors, but rarely in normal breast tissues, which was statistically correlated with advanced clinical stage and progesterone receptor status. Pharmacologic demethylation reactivated UCHL1 expression along with concomitant promoter demethylation. Ectopic expression of UCHL1 significantly suppressed the colony formation and proliferation of breast tumor cells, through inducing G0/G1 cell cycle arrest and apoptosis. Subcellular localization study showed that UCHL1 increased cytoplasmic abundance of p53. We further found that UCHL1 induced p53 accumulation and reduced MDM2 protein level, and subsequently upregulated the expression of p21, as well as cleavage of caspase3 and PARP, but not in catalytic mutant UCHL1 C90Sexpressed cells

The use of phylogeny to interpret cross-cultural patterns in plant use and guide medicinal plant discovery: an example from Pterocarpus (Leguminosae)

The study of traditional knowledge of medicinal plants has led to discoveries that have helped combat diseases and improve healthcare. However, the development of quantitative measures that can assist our quest for new medicinal plants has not greatly advanced in recent years. Phylogenetic tools have entered many scientific fields in the last two decades to provide explanatory power, but have been overlooked in ethnomedicinal studies. Several studies show that medicinal properties are not randomly distributed in plant phylogenies, suggesting that phylogeny shapes ethnobotanical use. Nevertheless, empirical studies that explicitly combine ethnobotanical and phylogenetic information are scarce.In this study, we borrowed tools from community ecology phylogenetics to quantify significance of phylogenetic signal in medicinal properties in plants and identify nodes on phylogenies with high bioscreening potential. To do this, we produced an ethnomedicinal review from extensive literature research and a multi-locus phylogenetic hypothesis for the pantropical genus Pterocarpus (Leguminosae: Papilionoideae). We demonstrate that species used to treat a certain conditions, such as malaria, are significantly phylogenetically clumped and we highlight nodes in the phylogeny that are significantly overabundant in species used to treat certain conditions. These cross-cultural patterns in ethnomedicinal usage in Pterocarpus are interpreted in the light of phylogenetic relationships.This study provides techniques that enable the application of phylogenies in bioscreening, but also sheds light on the processes that shape cross-cultural ethnomedicinal patterns. This community phylogenetic approach demonstrates that similar ethnobotanical uses can arise in parallel in different areas where related plants are available. With a vast amount of ethnomedicinal and phylogenetic information available, we predict that this field, after further refinement of the techniques, will expand into similar research areas, such as pest management or the search for bioactive plant-based compounds

Photo-designed terahertz devices

Technologies are being developed to manipulate electromagnetic waves using artificially structured materials such as photonic crystals and metamaterials, with the goal of creating primary optical devices. For example, artificial metallic periodic structures show potential for the construction of devices operating in the terahertz frequency regime. Here we demonstrate the fabrication of photo-designed terahertz devices that enable the real-time, wide-range frequency modulation of terahertz electromagnetic waves. These devices are comprised of a photo-induced, planar periodic-conductive structure formed by the irradiation of a silicon surface using a spatially modulated, femtosecond optical pulsed laser. We also show that the modulation frequency can be tuned by the structural periodicity, but is hardly affected by the excitation power of the optical pump pulse. We expect that our findings will pave the way for the construction of all-optical compact operating devices, such as optical integrated circuits, thereby eliminating the need for materials fabrication processes

Janus kinase 2 regulates Bcr–Abl signaling in chronic myeloid leukemia

Despite the success of imatinib mesylate (IM) in the early chronic phase of chronic myeloid leukemia (CML), patients are resistant to IM and other kinase inhibitors in the later stages of CML. Our findings indicate that inhibition of Janus kinase 2 (Jak2) in Bcr–Abl+ cells overcomes IM resistance although the precise mechanism of Jak2 action is unknown. Knocking down Jak2 in Bcr–Abl+ cells reduced levels of the Bcr–Abl protein and also the phosphorylation of Tyr177 of Bcr–Abl, and Jak2 overexpression rescued these knockdown effects. Treatment of Bcr–Abl+ cells with Jak2 inhibitors for 4–6 h but not with IM also reduced Bcr–Abl protein and pTyr177 levels. In vitro kinase experiments performed with recombinant Jak2 showed that Jak2 readily phosphorylated Tyr177 of Bcr–Abl (a Jak2 consensus site, YvnV) whereas c-Abl did not. Importantly, Jak2 inhibition decreased pTyr177 Bcr–Abl in immune complexes but did not reduce levels of Bcr–Abl, suggesting that the reduction of Bcr–Abl by Jak2 inhibition is a separate event from phosphorylation of Tyr177. Jak2 inhibition by chemical inhibitors (TG101209/WP1193) and Jak2 knockdown diminished the activation of Ras, PI-3 kinase pathways and reduced levels of pTyrSTAT5. These findings suggest that Bcr–Abl stability and oncogenic signaling in CML cells are under the control of Jak2

Normal Mouse Intestinal Epithelial Cells as a Model for the in vitro Invasion of Trichinella spiralis Infective Larvae

It has been known for many years that Trichinella spiralis initiates infection by penetrating the columnar epithelium of the small intestine; however, the mechanisms used by the parasite in the establishment of its intramulticellular niche in the intestine are unknown. Although the previous observations indicated that invasion also occurs in vitro when the infective larvae are inoculated onto cultures of intestinal epithelial cells (e.g., human colonic carcinoma cell line Caco-2, HCT-8), a normal readily manipulated in vitro model has not been established because of difficulties in the culture of primary intestinal epithelial cells (IECs). In this study, we described a normal intestinal epithelial model in which T. spiralis infective larvae were shown to invade the monolayers of normal mouse IECs in vitro. The IECs derived from intestinal crypts of fetal mouse small intestine had the ability to proliferate continuously and express specific cytokeratins as well as intestinal functional cell markers. Furthermore, they were susceptible to invasion by T. spiralis. When inoculated onto the IEC monolayer, infective larvae penetrated cells and migrated through them, leaving trails of damaged cells heavily loaded with T. spiralis larval excretory-secretory (ES) antigens which were recognized by rabbit immune sera on immunofluorescence test. The normal intestinal epithelial model of invasion mimicking the natural environment in vivo will help us to further investigate the process as well as the mechanisms by which T. spiralis establishes its intestinal niche