Acoustic transmission enhancement through a periodically-structured stiff plate without any opening

We report both experimentally and theoretically that the enhanced acoustic transmission can occur in the subwavelength region through a thin but stiff structured-plate without any opening. This exotic acoustic phenomenon is essentially distinct from the previous related studies originated from, either collectively or individually, the interaction of the incident wave with openings in previous structures. It is attributed to the structure-induced resonant excitation of the non-leaky Lamb modes that exist intrinsically in the uniform elastic plate. Our finding should have impact on ultrasonic applications.Comment: 11 pages, 4 figure

Plasma deposition of thin carbonfluorine films on aligned carbon nanotube

The thin film of carbonfluorine was deposited on the surfaces of aligned carbon nanotubes using a plasma polymerization treatment. High-resolution transmission electron microscopy images revealed that a thin film of the polymer layer (20 nm)(20nm) was uniformly deposited on the surfaces of the aligned carbon nanotubes. Time-of-flight secondary ion mass spectroscopy and Fourier transform infrared experiments identified the carbonfluorine thin films on the carbon nanotubes. The plasma deposition mechanism is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87850/2/043107_1.pd

Dynamic Phase Transition, Universality, and Finite-size Scaling in the Two-dimensional Kinetic Ising Model in an Oscillating Field

We study the two-dimensional kinetic Ising model below its equilibrium critical temperature, subject to a square-wave oscillating external field. We focus on the multi-droplet regime where the metastable phase decays through nucleation and growth of many droplets of the stable phase. At a critical frequency, the system undergoes a genuine non-equilibrium phase transition, in which the symmetry-broken phase corresponds to an asymmetric stationary limit cycle for the time-dependent magnetization. We investigate the universal aspects of this dynamic phase transition at various temperatures and field amplitudes via large-scale Monte Carlo simulations, employing finite-size scaling techniques adopted from equilibrium critical phenomena. The critical exponents, the fixed-point value of the fourth-order cumulant, and the critical order-parameter distribution all are consistent with the universality class of the two-dimensional equilibrium Ising model. We also study the cross-over from the multi-droplet to the strong-field regime, where the transition disappears

Vibrational biospectroscopy characterises biochemical differences between cell types used for toxicological investigations and identifies alterations induced by environmental contaminants

The use of cell-based assays is essential in reducing the number of vertebrates used in the investigation of chemical toxicities and in regulatory toxicology assessment. An important factor in obtaining meaningful results which can be accurately extrapolated is the use of biologically appropriate cell lines. In this preliminary study, ATR-FTIR spectroscopy with multivariate analysis was used to assess the fundamental biomolecular differences between a commonly used cell line, MCF-7 cells, and an environmentally relevant cell line derived from Mallard (Anas platyrhynchos) dermal fibroblasts. To better understand differences in basic cell biochemistry, the cells were analysed in the untreated state or post-exposure to PCB and PBDE congeners. The main spectral peaks in spectra from both cell types were associated with cellular macromolecules, particularly proteins and lipids but the spectra also revealed some cell-specific differences. Spectra from untreated Mallard fibroblasts spectra contained a large peak associated with lipids. The cell-related differences in lipid and DNA were also identified as regions of spectral alteration induced by PBDE and PCB exposure. Although lipid alterations were observed in post-treatment spectra from both cell types, these may be of more significance to Mallard fibroblasts, which may be due to increased intracellular lipid as determined by Nile red staining. Untreated MCF-7 cell spectra contained unique peaks related to DNA and nucleic acids. DNA associated spectral regions were also identified as areas of considerable alteration in MCF-7 cells exposed to some congeners including PBDE 47 and PCB 153. The findings indicate that in their native state, MCF-7 and Mallard cells have unique biochemical differences, which can be identified using ATR-FTIR spectroscopy. Such differences in biochemical composition differences, which may influence cell susceptibility to environmental contaminants and therefore influence the choice of cell type used in toxicology experiments. This is the first study to analyse the biochemistry of a Mallard dermal fibroblast cell line and to use ATR-FTIR spectroscopy for this purpose. ATR-FTIR spectroscopy is demonstrated as a useful tool for exploration of biomolecular variation at the cellular level and with further development, it could be used as part of a panel of cell-based assays to indicate when different results might be seen in environmental species compared to currently used cell lines. This article is protected by copyright. All rights reserve

A method for evaluating transport energy consumption in suburban areas

peer reviewedUrban sprawl is a major issue for sustainable development. It represents a significant contribution to energy consumption of a territory especially due to transportation requirements. However, transport energy consumption is rarely taken into account when the sustainability of suburban structures is studied. In this context, the paper presents a method to estimate transport energy consumption in residential suburban areas. The study aimed, on this basis, at highlighting the most efficient strategies needed to promote awareness and to give practical hints on how to reduce transport energy consumption linked to urban sprawl in existing and future suburban neighborhoods. The method uses data collected by using empirical surveys and GIS. An application of this method is presented concerning the comparison of four suburban districts located in Belgium to demonstrate the advantages of the approach. The influence of several parameters, such as distance to work places and services, use of public transport and performance of the vehicles, are then discussed to allow a range of different development situations to be explored. The results of the case studies highlight that travelled distances, and thus a good mix between activities at the living area scale, are of primordial importance for the energy performance, whereas means of transport used is only of little impact. Improving the performance of the vehicles and favoring home-work give also significant energy savings. The method can be used when planning new areas or retrofitting existing ones, as well as promoting more sustainable life styles regarding transport habits.SAFE (Suburban Areas Favoring Energy efficiency

How well do computer-generated faces tap face expertise?

The use of computer-generated (CG) stimuli in face processing research is proliferating due to the ease with which faces can be generated, standardised and manipulated. However there has been surprisingly little research into whether CG faces are processed in the same way as photographs of real faces. The present study assessed how well CG faces tap face identity expertise by investigating whether two indicators of face expertise are reduced for CG faces when compared to face photographs. These indicators were accuracy for identification of own-race faces and the other-race effect (ORE)-the well-established finding that own-race faces are recognised more accurately than other-race faces. In Experiment 1 Caucasian and Asian participants completed a recognition memory task for own- and other-race real and CG faces. Overall accuracy for own-race faces was dramatically reduced for CG compared to real faces and the ORE was significantly and substantially attenuated for CG faces. Experiment 2 investigated perceptual discrimination for own- and other-race real and CG faces with Caucasian and Asian participants. Here again, accuracy for own-race faces was significantly reduced for CG compared to real faces. However the ORE was not affected by format. Together these results signal that CG faces of the type tested here do not fully tap face expertise. Technological advancement may, in the future, produce CG faces that are equivalent to real photographs. Until then caution is advised when interpreting results obtained using CG faces

Magnetic alignment of carbon nanofibers in polymer composites and anisotropy of mechanical properties

Engineering applications of carbon nanofibers and nanotubes require their alignment in specific directions. Single-walled carbon nanotubes can be aligned in a magnetic field due to the presence of small amounts of catalyst elements, such as Ni and Co. However, for carbon nanofibers, their extremely low magnetic susceptibility is not sufficient for magnetically induced alignment. We present a method of solution-coating of NiO and CoO onto the surface of the carbon nanofibers. Due to the NiO- and CoO-coating, these nanofibers can be well aligned in the polymer composites under moderate magnetic field (3 T). Both transmission electron microscopy and scanning electron microscopy results show the well-aligned nanofibers in a polymer matrix. Mechanical testing shows a pronounced anisotropy in tensile strength in directions normal (12.1 MPa) and parallel (22 MPa) to the applied field, resulting from the well-aligned nanofibers in the polymer matrix. The mechanism of magnetic alignment due to coating of NiO and CoO on the nanofiber surface is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87644/2/064312_1.pd

Monophyletic origin of domestic bactrian camel (Camelus bactrianus) and its evolutionary relationship with the extant wild camel (Camelus bactrianus ferus)

The evolutionary relationship between the domestic bactrian camel and the extant wild two-humped camel and the factual origin of the domestic bactrian camel remain elusive. We determined the sequence of mitochondrial cytb gene from 21 camel samples, including 18 domestic camels (three Camelus bactrianus xinjiang, three Camelus bactrianus sunite, three Camelus bactrianus alashan, three Camelus bactrianus red, three Camelus bactrianus brown and three Camelus bactrianus normal) and three wild camels (Camelus bactrianus ferus). Our phylogenetic analyses revealed that the extant wild two-humped camel may not share a common ancestor with the domestic bactrian camel and they are not the same subspecies at least in their maternal origins. Molecular clock analysis based on complete mitochondrial genome sequences indicated that the sub-speciation of the two lineages had begun in the early Pleistocene, about 0.7 million years ago. According to the archaeological dating of the earliest known two-humped camel domestication (5000–6000 years ago), we could conclude that the extant wild camel is a separate lineage but not the direct progenitor of the domestic bactrian camel. Further phylogenetic analysis suggested that the bactrian camel appeared monophyletic in evolutionary origin and that the domestic bactrian camel could originate from a single wild population. The data presented here show how conservation strategies should be implemented to protect the critically endangered wild camel, as it is the last extant form of the wild tribe Camelina

The Effects of the Acupuncture Treatment for Smoking Cessation in High School Student Smokers

The use of alternative medicine for smoking cessation have been increasing steadily in recent years. A series of clinical group studies was performed to clarify the effect, outcome and success rate of an acupuncture treatment for smoking cessation. This study was conducted for four weeks using 238 smoking students at 2 high schools. The subjects were separated into two groups: 159 students were treated with acupuncture on the anti-smoking acupoints of the ear, which is known to be effective for cessation of smoking (case group), and 79 students were treated at other sites of the ear (control group). The acupuncture treatment was alternately administered at each side of the ears on a weekly basis for 4 weeks. The smoking cessation success was only 1 case (0.6%) in the case group and none in the control group after 4 weeks. The change in the taste of tobacco and the intensity of the desire to smoke were not significantly different between the case and control groups, but the case group showed a tendency of reduction in the taste of tobacco and the intensity of the desire to smoke. In addition, the reduction in cigarette consumption was not significant, but the tendency of reduction in the study group was significant. It is believed that the site of auricular acupuncture for smoking cessation is not important. However, there was a significant tendency in terms of the reduction in cigarette consumption, the taste of tobacco and the intensity of the desire to smoke in the case group, indicating that auricular acupuncture in smoking cessation has some effect

Divergent human remodeling complexes remove nucleosomes from strong positioning sequences

Nucleosome positioning plays a major role in controlling the accessibility of DNA to transcription factors and other nuclear processes. Nucleosome positions after assembly are at least partially determined by the relative affinity of DNA sequences for the histone octamer. Nucleosomes can be moved, however, by a class of ATP dependent chromatin remodeling complexes. We recently showed that the human SWI/SNF remodeling complex moves nucleosomes in a sequence specific manner, away from nucleosome positioning sequences (NPSes). Here, we compare the repositioning specificity of five remodelers of diverse biological functions (hSWI/SNF, the SNF2h ATPase and the hACF, CHRAC and WICH complexes than each contain SNF2h) on 5S rDNA, MMTV and 601 NPS polynucleosomal templates. We find that all five remodelers act similarly to reduce nucleosome occupancy over the strongest NPSes, an effect that could directly contribute to the function of WICH in activating 5S rDNA transcription. While some differences were observed between complexes, all five remodelers were found to result in surprisingly similar nucleosome distributions. This suggests that remodeling complexes may share a conserved repositioning specificity, and that their divergent biological functions may largely arise from other properties conferred by complex-specific subunits