bluuebunny/crossref_metadata_2025 huggingface dataset:
Imaging of hemoglobin oxygen saturation ratio in the face by spectral camera and its application to evaluate dark circles
Authors: Kikuchi Kumiko , Masuda Yuji , Hirao Tetsuji
Published: June 2013

Background

Contact‐type spectrophotometers have been widely used to measure skin color to determine the color values and melanin and hemoglobin contents. Recently, a spectral camera was introduced to evaluate two‐dimensional color distribution. However, its application to skin color measurement has been limited.

Methods

The original spectral imaging system developed for facial skin consisted of a spectral camera and an original lighting unit for uniform irradiation of the face. The distribution of skin chromophores in the face, including melanin and oxy‐ and deoxyhemoglobin, was calculated from the reflectance data for each pixel of the spectral images. In addition, to create a mean spectral image of the group, a face morphing technology for spectral data was proposed. Using the system, we determined the characteristics of the dark circles around the eyes and also evaluated the effects of an anti‐dark circle cosmetic.

Results

This system enabled the sensitive detection of skin chromophores in the face. Melanin content increased and hemoglobin oxygen saturation ratio decreased locally in the infraorbital areas of women with dark circles compared with those of women without dark circles. In addition, we were able to detect improvement in the dark circles after 6 weeks' use of anti‐dark circle cosmetic products by visualizing the distribution of the relative concentrations of melanin and hemoglobin oxygen saturation ratio.

Conclusion

Using a spectral camera, we developed a non‐contact image‐processing system that was capable of capturing a wide area of the face to visualize the distribution of the relative concentrations of skin chromophores in the face.
Characterization of Chinese body skin through in vivo instrument assessments, visual evaluations, and questionnaire: influences of body area, inter‐generation, season, sex, and skin care habits
Authors: Li Xi , Galzote Carlos , Yan Xiuyuan , Li Li , Wang Xi
Published: June 2013

Background/Purpose

The varying influence of multiple factors (e.g., aging, sex, season, skin care habits) on skin structure and function necessitates study within ethnic groups to fully characterize their skin.

Methods

Men and women aged 40–50 years (n = 43) and their consanguineous same‐sex children, aged 18–25 years (n = 43), living in Chengdu, China were enrolled in this single center, non‐interventional study. Volunteers attended two study visits (summer, 2010 and winter, 2011) at which dermatologists measured transepidermal water loss (TEWL), skin hydration, sebum secretion, fine lines/roughness, melanin/erythema, temperature, and color, and clinically graded participants' skin. Participants answered a questionnaire, indicating their perceived skin type/condition. Data were analyzed using t‐test/anova or Friedman/Wilcoxon test.

Results

Objective measurements demonstrated statistically significant inter‐generational differences in skin condition, with aged skin more wrinkled at most sites, having reduced oil/colder facial and décolletage skin, darker/more erythematous skin in exposed areas, and less hydrated/rougher heel skin; similarities were detected in skin melanin, erythema, and TEWL. There were also statistically significant differences between seasons and sexes. The intersection between instrument measurements and subjective perceptions of skin revealed notable differences.

Conclusion

Objective measurements and their intersection with subjective perceptions demonstrate the influences of inter‐generation, season, sex, and living habits on Chinese body skin.
Analysis of the skin surface and inner structure around pores on the face
Authors: Mizukoshi Koji , Takahashi Kazuhiro
Published: June 2013

Background/purpose

Facial pores do not appear to close again in old skin. Therefore, the tissue structure around the pore has been speculated to keep the pore open. To elucidate the reason for pore enlargement, we examined the relationship between the skin surface and inner skin structural characteristics in the same regions especially around the pore.

Methods

Samples of the skin surface were obtained from the cheek and examined using a laser image processor to obtain three‐dimensional (3D) data. The inner structure of the skin was analyzed using in vivo confocal laser scanning microscopy (CLSM).

Results

The conspicuous pore not only had a concave structure but also a discontinuous convex structure on the skin surface surrounding the pore. Furthermore, CLSM image indicated that the skin inner structure developed a discontinuous dermal papilla structure and isotropic dermal fiber structure.

Conclusion

There were structural changes in the skin surface around conspicuous pores, including not only a concave structure but also a convex structure with skin inner structure changing.
Depigmented skin and phantom color measurements for realistic prostheses
Authors: Tanner Paul , Leachman Sancy , Boucher Kenneth , Ozçelik Tunçer Burak
Published: June 2013

Purpose

The purpose of this study was to test the hypothesis that regardless of human skin phototype, areas of depigmented skin, as seen in vitiligo, are optically indistinguishable among skin phototypes. The average of the depigmented skin measurements can be used to develop the base color of realistic prostheses.

Methods and Materials

Data was analyzed from 20 of 32 recruited vitiligo study participants. Diffuse reflectance spectroscopy measurements were made from depigmented skin and adjacent pigmented skin, then compared with 66 pigmented polydimethylsiloxane phantoms to determine pigment concentrations in turbid media for making realistic facial prostheses.

Results

The Area Under spectral intensity Curve (AUC) was calculated for average spectroscopy measurements of pigmented sites in relation to skin phototype (P = 0.0505) and depigmented skin in relation to skin phototype (P = 0.59). No significant relationship exists between skin phototypes and depigmented skin spectroscopy measurements. The average of the depigmented skin measurements (AUC 19,129) was the closest match to phantom 6.4 (AUC 19,162).

Conclusion

Areas of depigmented skin are visibly indistinguishable per skin phototype, yet spectrometry shows that depigmented skin measurements varied and were unrelated to skin phototype. Possible sources of optical variation of depigmented skin include age, body site, blood flow, quantity/quality of collagen, and other chromophores. The average of all depigmented skin measurements can be used to derive the pigment composition and concentration for realistic facial prostheses.
Transmission disequilibrium analysis of 31 type 1 diabetes susceptibility loci in Finnish families
Authors: Laine A. P. , Knip M. , Ilonen J. ,   The Finnish Pediatric Diabetes Register
Published: June 2013

Currently more than 50 type 1 diabetes (T1D) loci outside the human leukocyte antigen (HLA)‐region have been established in large European and/or North American populations. Our aim was to attempt to replicate these findings in the less heterogenic Finnish population and to explore evidence for genetic heterogeneity. We analyzed 1761 Finnish T1D trio families for association in 31 T1D loci (25 confirmed and 6 have inconsistent prior evidence). Families were categorized into nine different subgroups according to potential features that reflect underlying genetic heterogeneity in patients (age at diagnosis, sex and HLA genotypes). Seventeen confirmed loci and one nonconfirmed locus (1p31.1) presented significant evidence for association in the full data set. Magnitude and direction of effect was consistent with prior evidence. The strongest effects were seen at the insulin gene, PTPN22 and IL2RA regions. Tentative evidence of odds ratio (OR) heterogeneity within subgroups was seen in eight loci. Our findings were well in line with those reported in the latest meta‐analyses using large admixed Caucasian populations, which concurs with the notion that the currently confirmed T1D loci, that have been discovered and replicated mostly in diverse populations, are common to all European populations. The observed effect modifications by subgrouping require validation in later studies with more statistical power.
A Temporal Variant‐Invariant Validation Approach for Agent‐based Models of Landscape Dynamics
Authors: Bone Christopher , Johnson Bart , Nielsen‐Pincus Max , Sproles Eric , Bolte John
Published: June 2013

Agent‐based modeling provides a means for addressing the way human and natural systems interact to change landscapes over time. Until recently, evaluation of simulation models has focused on map comparison techniques that evaluate the degree to which predictions match real‐world observations. However, methods that change the focus of evaluation from patterns to processes have begun to surface; that is, rather than asking if a model simulates a correct pattern, models are evaluated on their ability to simulate a process of interest. We build on an existing agent‐based modeling validation method in order to present a temporal variant‐invariant analysis (TVIA). The enhanced method, which focuses on analyzing the uncertainty in simulation results, examines the degree to which outcomes from multiple model runs match some reference to how land use parcels make the transition from one land use class to another over time. We apply TVIA to results from an agent‐based model that simulates the relationships between landowner decisions and wildfire risk in the wildland‐urban interface of the southern Willamette Valley, Oregon, USA. The TVIA approach demonstrates a novel ability to examine uncertainty across time to provide an understanding of how the model emulates the system of interest.
A Comparative Analysis of Traveling Salesman Solutions from Geographic Information Systems
Authors: Curtin Kevin M. , Voicu Gabriela , Rice Matthew T. , Stefanidis Anthony
Published: June 2013

The Traveling Salesman Problem is one of the most prominent problems in combinatorial optimization, and is regularly employed in a wide variety of applications. The objective of this article is to demonstrate the extent of sub‐optimality produced by Traveling Salesman solution procedures implemented in the context of Geographic Information Systems and to discuss the consequences that such solutions have for practice. Toward that end, an analysis is made of Traveling Salesman solutions from implementations in four Geographic Information System packages. These implementations are tested against the optimal solution for a range of problem sizes. Computational results are presented in the context of a school bus routing application. This analysis concludes that no Traveling Salesman implementation in GIS is likely to find the optimal solution when problems exceed 10 stops. In contrast, optimal solutions can be generated with desktop linear programming software for up to 25 cities. Moreover, one GIS implementation consistently found solutions that were closer to optimal than its competitors. This research strongly suggests that for applications with fewer than 25 stops, the use of an optimal solution procedure is advised, and that GIS implementations can benefit from the integration of more robust optimization techniques.
Evidence of purinergic neurotransmission in isolated, intact horse sweat glands
Authors: Bovell Douglas L. , Riggs Christopher M. , Sidlow Gordon , Troester Suzanne , MacLaren William , Yip Wallace , Ko Wing H.
Published: June 2013

Background

Fluid secretion by sweat glands in response to heat and exercise is underpinned by increases in intracellular calcium. In horses, this is primarily via β2‐adrenoceptors, but studies in equine sweat gland cell lines have indicated a possible role for purinergic agonists. Knowledge of equine sweating stimulus–secretion mechanisms in intact glands from healthy animals would allow future comparison to determine whether these mechanisms are affected in equine anhidrosis.

Hypothesis/Objectives

To determine whether purinergic agonists can induce changes in intracellular calcium in intact, freshly isolated equine sweat glands.

Animals

Eleven healthy thoroughbred horses from the Hong Kong Jockey Club were used in this study.

Methods

Freshly isolated equine sweat glands were loaded with the calcium‐sensitive fluorescent dye fura‐2 AM, and changes in intracellular calcium were recorded before, during and after stimulation by purinergic agonists.

Results

Purinergic agonists ATP and UTP generated significant increases in intracellular calcium.

Conclusions and clinical importance

The results show that it is possible to investigate stimulus–secretion coupling mechanisms by fluorescence imaging in equine sweat glands that have been isolated from fresh skin samples. Such isolated glands retain functional β2‐adrenoceptors and P2Y purinergic receptors that couple to a calcium‐signalling pathway. Using isolated, intact sweat glands therefore offers a very useful model for the further study of secretory processes in equine sweat glands, and using this experimental approach could facilitate a better understanding of how these mechanisms are affected in equine anhidrosis.
Transmission of Streptococcus dysgalactiae subsp. equisimilis between Child and Dog in an Aboriginal Australian Community
Authors: Schrieber L. , Towers R. , Muscatello G. , Speare R.
Published: June 2013

Streptococcus dysgalactiae subsp. equisimilis (SDSE), also known as group G and C streptococci, is becoming increasingly recognized as a pathogen in humans. We report here the finding of an identical strain of SDSE in the throat of a child and their dog in an Aboriginal Australian community. The strain was identified using the API 20Strep system, 16S rRNA gene sequencing, emm sequence typing (emmST) and multilocus sequence typing (MLST) as a group C SDSE, stC839.5 and ST‐3. Carriage of this strain by a human and dog in the same household justifies detailed epidemiological studies using molecular typing to clarify the extent of cross‐species transmission and sharing of SDSE and other group G and C streptococci, and its impact in these communities.
Feedback Ramp Metering Using Godunov Method Based Hybrid Model
Authors: Shlayan Neveen , Kachroo Pushkin
Published: June 2013

In this paper, a new feedback control design for an isolated freeway ramp is presented utilizing hybrid dynamics based on Godunov's numerical technique. Previous feedback ramp metering designs have been mainly based on either discretized linearized methods such as ALINEA or nonlinear feedback designs based on ordinary differential equations for the traffic model. These models use lumped parameters, which fail to represent some details of the rarefaction wave phenomenon of the distributed model. Godunov's conditions employ the data known on both sides of each boundary in order to determine the characteristics of the boundary conditions. This paper uses Godunov's hybrid lumped model based on which feedback control design is proposed and simulation results for the model are presented. Real data is collected on one of the major freeway on-ramps in the Las Vegas area. The roadway parameters are estimated using least squares estimator then are used in the proposed Godunov based hybrid model. The proposed feedback ramp control design is compared with the actual ramp control algorithm. Self-tuning adaptive control is also performed using recursive parameter updating with and without exponential forgetting.
Jet-Surface Interaction Test: Far-Field Noise Results
Authors: Brown Clifford A.
Published: June 2013

Many configurations proposed for the next generation of aircraft rely on the wing or other aircraft surfaces to shield the engine noise from the observers on the ground. However, the ability to predict the shielding effect and any new noise sources that arise from the high-speed jet flow interacting with a hard surface is currently limited. Furthermore, quality experimental data from jets with surfaces nearby suitable for developing and validating noise prediction methods are usually tied to a particular vehicle concept and, therefore, very complicated. The Jet-Surface Interaction Tests are intended to supply a high quality set of data covering a wide range of surface geometries and positions and jet flows to researchers developing aircraft noise prediction tools. The initial goal is to measure the noise of a jet near a simple planar surface while varying the surface length and location in order to: (1) validate noise prediction schemes when the surface is acting only as a jet noise shield and when the jet-surface interaction is creating additional noise, and (2) determine regions of interest for future, more detailed, tests. To meet these objectives, a flat plate was mounted on a two-axis traverse in two distinct configurations: (1) as a shield between the jet and the observer and (2) as a reflecting surface on the opposite side of the jet from the observer. The surface length was varied between 2 and 20 jet diameters downstream of the nozzle exit. Similarly, the radial distance from the jet centerline to the surface face was varied between 1 and 16 jet diameters. Far-field and phased array noise data were acquired at each combination of surface length and radial location using two nozzles operating at jet exit conditions across several flow regimes: subsonic cold, subsonic hot, underexpanded, ideally expanded, and overexpanded supersonic. The far-field noise results, discussed here, show where the jet noise is partially shielded by the surface and where jet-surface interaction noise dominates the low frequency spectrum as a surface extends downstream and approaches the jet plume.
Error Analysis of a 3-DOF Parallel Mechanism for Milling Applications
Authors: Gojtan G. E. E. , Furtado G. P. , Hess-Coelho T. A.
Published: June 2013

Parallel mechanisms have been investigated during the last two decades, due to the fact that they present some advantages in a comparison with serial structures. This work deals with the error analysis of a 3-dof asymmetric parallel mechanism, purposely conceived for milling applications. In a comparison with the previous proposed concepts, this type of kinematic structure demonstrates a promising behavior. Topologically, the architecture is simpler and lighter than Tricept because it has no central passive limb. In addition, only the constraining active limb needs to satisfy the parallelism and orthogonality conditions. Furthermore, one degree of freedom, associated to the third actuator, is decoupled from the other two. Important issues, related to this type of kinematic structure, such as the mappings of the tool positioning error throughout the available workspace, due to the actuators imprecisions and manufacturing tolerances, are discussed in detail.
Polar Decomposition of Unit Dual Quaternions
Authors: Purwar Anurag , Ge Q. J.
Published: June 2013

This paper seeks to extend the notion of polar decomposition (PD) from matrix algebra to dual-quaternion algebra. The goal is to obtain a simple, efficient and explicit method for determining the PD of spatial displacements in Euclidean three-space that belong to a special Euclidean Group known as SE(3). It has been known that such a decomposition is equivalent to the projection of an element of SE(3) onto SO(4) that yields hyper spherical displacements that best approximate rigid-body displacements. It is shown in this paper that a dual quaternion representing an element of SE(3) can be decomposed into a pair of unit quaternions, called double quaternion, that represents an element of SO(4). Furthermore, this decomposition process may be interpreted as the projection of a point in four-dimensional space onto a unit hypersphere. An example is provided to illustrate that the results obtained from this dual-quaternion based polar decomposition are same as those obtained from the matrix based polar decomposition.
Kinematic Design of an Underactuated Robot Leg for Passive Terrain Adaptability and Stability
Authors: Kanner Oren Y. , Dollar Aaron M.
Published: June 2013

This paper investigates how the passive adaptability of an underactuated robot leg to uneven terrain is affected by variations in design parameters. In particular, the joint torque coupling ratio, segment length ratio, and rest angles are varied to determine configurations that allow for maximum terrain roughness adaptability while minimizing the transmission of disturbance forces to the body. In addition, a series of alternate leg actuation configurations are considered. The results show that a proximal/distal joint torque coupling ratio of 2 with an inverted distal joint, a proximal/distal leg length ratio of 1.25, and an initial proximal joint angle of −53 deg maximize the terrain variability over which the robot can remain stable by exerting a near-constant vertical reaction force while minimizing lateral force and moment disturbances. In addition, the spring stiffness ratio allows for a tradeoff to be made between the different performance metrics. Finally, the robot's stability with respect to its posture is discussed.
Inverse Geometrico-Static Problem of Underconstrained Cable-Driven Parallel Robots With Three Cables1
Authors: Carricato Marco
Published: June 2013

This paper studies underconstrained cable-driven parallel robots (CDPRs) with three cables. A major challenge in the study of these robots is the intrinsic coupling between kinematics and statics, which must be tackled simultaneously. Effective elimination procedures are presented which provide the complete solution sets of the inverse geometrico-static problems (IGPs) with assigned orientation or position. In the former case, the platform orientation is given, whereas the platform position and the cable lengths and tensions must be computed. In the latter case, the platform position is known, whereas the platform orientation and the cable lengths and tensions are to be calculated. The described problems are proven to admit at the most 1 and 24 real solutions, respectively.
Improvement in Ballistae Design From Eutitonon to Palintonon: A Study
on the Mechanical Advantages
Authors: Rossi C. , Pagano S.
Published: June 2013

This study investigated why the design of ancient throwing machines evolved from eutitonon (arms outside the mainframe) to palintonon (arms inside the mainframe) from the end of the first century B.C. to the first century A.D. and evaluated the mechanical advantages of the new design. Palintonon was first used for big machines; in the following centuries, it was also used for much smaller machines. Essentially, the palintonon design has several advantages: more elastic energy can be stored in the hair bundles representing the motors of these machines, heavier projectiles can be thrown with the same charging effort, projectiles are stressed by lower acceleration in the machine with the same muzzle velocity, and the throwing machines have higher efficiency. Results are also presented regarding the “internal ballistics” of these ancient throwing machines by using simulation software.
Subharmonic Resonance Cascades in a Class of Coupled Resonators
Authors: Strachan B. Scott , Shaw Steven W. , Kogan Oleg
Published: June 2013

We consider a chain of N nonlinear resonators with natural frequency ratios of approximately 2:1 along the chain and weak nonlinear coupling that allows energy to flow between resonators. Specifically, the coupling is such that the response of one resonator parametrically excites the next resonator in the chain, and also creates a resonant back-action on the previous resonator in the chain. This class of systems, which is a generic model for passive frequency dividers, is shown to have rich dynamical behavior. Of particular interest in applications is the case when the high frequency end of the chain is resonantly excited, and coupling results in a cascade of subharmonic bifurcations down the chain. When the entire chain is activated, that is, when all N resonators have nonzero amplitudes, if the input frequency on the first resonator is Ω, the terminal resonator responds with frequency Ω/2N. The details of the activation depend on the strength and frequency of the input, the level of resonator dissipation, and the frequency mistuning in the chain. In this paper we present analytical results, based on perturbation methods, which provide useful predictions about these responses in terms of system and input parameters. Parameter conditions for activation of the entire chain are derived, along with results about other phenomena, such as the period doubling accumulation to full activation, and regions of multistability. We demonstrate the utility of the predictive results by direct comparison with simulations of the equations of motion, and we also present a sample mechanical system that embodies the desired properties. These results are useful for the design and operation of mechanical frequency dividers that are based on subharmonic resonances.
A Numerical Investigation of Combustion and Mixture Formation in a Compressed Natural Gas DISI Engine With Centrally Mounted Single-Hole Injector
Authors: Yadollahi B. , Boroomand M.
Published: June 2013

Direct injection of natural gas into the cylinder of spark ignition (SI) engines has shown a great potential to achieve the best fuel economy and reduced emission levels. Since the technology is rather new, in-cylinder flow phenomena have not been completely investigated. In this study, a numerical model has been developed in AVL FIRE software to perform an investigation of natural gas direct injection into the cylinder of spark ignition internal combustion engines. In this regard, two main parts have been taken into consideration aiming to convert a multipoint port fuel injection (MPFI) gasoline engine to a direct injection natural gas (NG) engine. In the first part of the study, multidimensional simulations of transient injection process, mixing, and flow field have been performed. Using the moving mesh capability, the validated model has been applied to methane injection into the cylinder of a direct injection engine. Five different piston head shapes have been taken into consideration in the investigations. An inwardly opening single-hole injector has been adapted to all cases. The injector location has been set to be centrally mounted. The effects of combustion chamber geometry have been studied on the mixing of air-fuel inside the cylinder via the quantitative and qualitative representation of results. In the second part, an investigation of the combustion process has been performed on the selected geometry. The spark plug location and ignition timing have been studied as two of the most important variables. Simulation of transient injection was found to be a challenging task because of required computational effort and numerical instabilities. Injection results showed that the narrow bowl piston head geometry is the most suited geometry for NG direct injection (DI) application. A near center position has been shown to be the best spark plug location based on the combustion studies. It has been shown that advanced ignitions timings of up to 50 degrees crank angle ( °CA) should be used in order to obtain better combustion performance.
Effects of He and Ar ion kinetic energies in protection of organosilicate glass from O2 plasma damage
Authors: Lee Joe , Kazi Haseeb , Gaddam Sneha , Kelber Jeffry A. , Graves David B.
Published: June 2013

In-situ x-ray photoelectron spectroscopy (XPS) and ex-situ Fourier transform infrared studies of He plasma and Ar+ ion bombardment pretreatments of organosilicate glass demonstrate that such pretreatments inhibit subsequent O2 plasma-induced carbon loss by forming a SiO2-like damaged overlayer, and that the degree of protection correlates directly with increased ion kinetic energies, but not with the thickness of the SiO2 overlayer. This thickness is observed by XPS to be roughly constant and <1 nm regardless of ion energies involved. The data indicate that ion kinetic energies are an important parameter in protective noble gas plasma pretreatments to inhibit O2 plasma-induced carbon loss.
Nonvolatile memory characteristics of thin-film transistors using hybrid gate stack composed of solution-processed indium-zinc-silicon oxide active channel and organic ferroelectric gate insulator
Authors: Bak Jun Yong , Yoon Sung Min
Published: June 2013

Organic-ferroelectric oxide memory thin-film transistors (OfeOx-MTFTs) were fabricated using a solution-processed indium-zinc-silicon oxide (IZSiO) active channel and a poly(vinylidene fluoride-trifluoroethylene) ferroelectric gate insulator and characterized to improve device properties such as field-effect mobility (μsat), program speed, and retention time by controlling the IZSiO channel composition. The compositions of IZSiO semiconducting layers were adjusted with different Si amounts of 0, 2, 5, and 10 mol. %. The incorporation of Si in IZSiO channel layer modulated the carrier concentration and reduced defect densities within the channel; among the fabricated OfeOx-MTFT devices, those with IZSiO of 2 mol. % Si content exhibited the best overall performance with μsat, subthreshold swing, memory window, and ratio of on/off programmed currents measured to be 23.3 cm2 V−1 s−1, 772 mV/decade, 11.9 V, and 5.7 × 105, respectively. Incorporating a suitable amount of Si optimized the compromise between the carrier concentration and defect densities within the channel, improving the OfeOx-MTFT program speed and program endurance as well as its data retention properties.
Effects of introgression on the genetic population structure of two ecologically and economically important conifer species: lodgepole pine (Pinus contortavar.latifolia) and jack pine (Pinus banksiana)
Authors: Cullingham Catherine I. , Cooke Janice E.K. , Coltman David W.
Published: June 2013

Forest trees exhibit a remarkable range of adaptations to their environment, but as a result of frequent and long-distance gene flow, populations are often only weakly differentiated. Lodgepole and jack pine hybridize in western Canada, which adds the opportunity for introgression through hybridization to contribute to population structure and (or) adaptive variation. Access to large sample size, high density SNP datasets for these species would improve our ability to resolve population structure, parameterize introgression, and separate the influence of demography from adaptation. To accomplish this, 454 transcriptome reads for lodgepole and jack pine were assembled using Newbler and MIRA, the assemblies mined for SNPs, and 1536 SNPs were selected for typing on lodgepole pine, jack pine, and their hybrids (N = 536). We identified population structure using both Bayesian clustering and discriminate analysis of principle components. Introgressed SNP loci were identified and their influence on observed population structure was assessed. We found that introgressed loci resulted in increased differentiation both within lodgepole and jack pine populations. These findings are timely given the recent mountain pine beetle population expansion in the hybrid zone, and will facilitate future studies of adaptive traits in these ecologically important species.
NONCOMMUTATIVE GRAPHENE
Authors: BASTOS CATARINA , BERTOLAMI ORFEU , DIAS NUNO COSTA , PRATA JOÃO NUNO
Published: June 2013

We consider a noncommutative description of graphene. This description consists of a Dirac equation for massless Dirac fermions plus noncommutative corrections, which are treated in the presence of an external magnetic field. We argue that, being a two-dimensional Dirac system, graphene is particularly interesting to test noncommutativity. We find that momentum noncommutativity affects the energy levels of graphene and we obtain a bound for the momentum noncommutative parameter.
USE OF STRAIN GRADIENT THEORY FOR MODELING THE SIZE-DEPENDENT PULL-IN OF ROTATIONAL NANO-MIRROR IN THE PRESENCE OF MOLECULAR FORCE
Authors: BENI Y. TADI , ABADYAN M.
Published: June 2013

Experiments reveal that mechanical behavior of nanostructures is size-dependent. Herein, the size dependent pull-in instability of torsional nano-mirror is investigated using strain gradient nonclassic continuum theory. The governing equation of the mirror is derived taking the effect of electrostatic Coulomb and molecular van der Waals (vdW) forces into account. Variation of the rotation angle of the mirror as a function of the applied voltage is obtained and the instability parameters i.e., pull-in voltage and pull-in angle are determined. Nano-mirrors with square and circular cross-sectional beams are investigated as case studies. It is found that when the thickness of the torsional nano-beam is comparable with the intrinsic material length scales, size effect can substantially increase the instability parameters of the rotational mirror. Moreover, the effect of vdW forces on the size-dependent pull-in instability of the system is discussed. The proposed model is able to predict the experimental results more accurately than the previous classic models and reduce the gap between experiment and previous theories.
LOW-POWER, LOW-VOLTAGE, DUAL-OUTPUT, SECOND GENERATION CURRENT CONVEYOR AND ITS APPLICATION IN LOW-PASS FILTER DESIGN
Authors: MAGHAMI MOHAMMAD HOSSEIN , SODAGAR AMIR M.
Published: June 2013

A new simple dual-output second generation current conveyor (DO-CCII) circuit is proposed. Designed in a standard 0.5-μm CMOS process, the circuit operates at ±1.5 V supply voltages with a total power consumption of 106 nW. Main characteristics of the proposed DO-CCII are its simplicity, small silicon area consumption, and not suffering from the body effect of MOS transistors. The proposed circuit is employed to implement a first-order low-pass filter with upper -3 dB cut-off frequency of as low as 3.2 Hz.
ON THE WELL-POSEDNESS OF A 2D NONLINEAR AND NONLOCAL SYSTEM ARISING FROM THE DISLOCATION DYNAMICS
Authors: LI DONG , MIAO CHANGXING , XUE LIUTANG
Published: June 2013

In this paper we consider a 2D nonlinear and nonlocal model describing the dynamics of the dislocation densities. We prove the local well-posedness of strong solution in the suitable functional framework, and we show the global well-posedness for some dissipative cases by the method of nonlocal maximum principle.
RADIAL SYMMETRY OF POSITIVE SOLUTIONS TO EQUATIONS INVOLVING THE FRACTIONAL LAPLACIAN
Authors: FELMER PATRICIO , WANG YING
Published: June 2013

The aim of this paper is to study radial symmetry and monotonicity properties for positive solution of elliptic equations involving the fractional Laplacian. We first consider the semi-linear Dirichlet problem [Formula: see text] where (-Δ)αdenotes the fractional Laplacian, α ∈ (0, 1), and B1denotes the open unit ball centered at the origin in ℝNwith N ≥ 2. The function f : [0, ∞) → ℝ is assumed to be locally Lipschitz continuous and g : B1→ ℝ is radially symmetric and decreasing in |x|. In the second place we consider radial symmetry of positive solutions for the equation [Formula: see text] with u decaying at infinity and f satisfying some extra hypothesis, but possibly being non-increasing.

Our third goal is to consider radial symmetry of positive solutions for system of the form [Formula: see text] where α1, α2∈(0, 1), the functions f1and f2are locally Lipschitz continuous and increasing in [0, ∞), and the functions g1and g2are radially symmetric and decreasing. We prove our results through the method of moving planes, using the recently proved ABP estimates for the fractional Laplacian. We use a truncation technique to overcome the difficulty introduced by the non-local character of the differential operator in the application of the moving planes.
SINGULAR LIMITS FOR 2-DIMENSIONAL ELLIPTIC NEUMANN PROBLEM WITH EXPONENTIAL NONLINEARITY AND SINGULAR DATA
Authors: CHANG YIBIN , YANG HAITAO
Published: June 2013

In this paper, by using the finite-dimensional Lyapunov–Schmidt reduction method, we prove the existence of mixed interior-boundary concentrating solutions for a 2-dimensional elliptic Neumann problem with exponential nonlinearity and singular sources.
LIOUVILLIAN INTEGRABILITY OF A DETERMINISTIC BUSINESS CYCLE MODEL
Authors: VALLS CLÀUDIA
Published: June 2013

We introduce a deterministic business cycle model and study its dynamics by determining the existence of nonconstant functions which can be obtained "by quadratures" of elementary functions and are constant on solution curves in some nonempty open set.
LAYERED SOLUTIONS WITH CONCENTRATION ON LINES IN THREE-DIMENSIONAL DOMAINS
Authors: AO WEIWEI , YANG JUN
Published: June 2013

We consider the following singularly perturbed elliptic problem [Formula: see text] where Ω is a bounded domain in ℝ3with smooth boundary, ε is a small parameter, 1 < p < ∞, ν is the outward normal of ∂Ω. We employ techniques already developed in [39] to extend their result to three-dimensional domain. More precisely, let Γ be a straight line intersecting orthogonally with ∂Ω at exactly two points and satisfying a non-degenerate condition. We establish the existence of a solution uεconcentrating along a curve [Formula: see text] near Γ, exponentially small in ε at any positive distance from the curve, provided ε is small and away from certain critical numbers. The concentrating curve [Formula: see text] will collapse to Γ as ε → 0.
On the limit cycle bifurcation of a polynomial system from a global center
Authors: Xiong Yanqin , Han Maoan
Published: June 2013

In this paper, we consider a quadratic system with a global center under polynomial perturbations of degree n(n ≥ 1). By using the first-order Melnikov function, we study Poincaré and Poincaré–Andronov–Hopf bifurcations. We prove that both Poincaré and Hopf cyclicity are n for n ≥ 2 up to the first order in ε.
WAVE REFLECTION IN PIEZOELECTRIC HALF-PLANE
Authors: YUAN XIAOGUANG , ZHU Z. H.
Published: June 2013

The assumption of quasi-static electric field in the problem of wave reflection in piezoelectric half-plane results in missing an independent electric wave mode at the piezoelectric boundary, which leads to oversimplified solutions of reflected waves in a strong piezoelectric medium if only elastic bulk wave boundary conditions are considered. The paper presents a novel solution to address the issue by using the inhomogeneous wave theory and introducing a virtual reflection wave mode in addition to the elastic bulk wave modes. The virtual wave is assumed to satisfy the Snell's law as well as the piezoelectric boundary condition and can be treated in the same way as the elastic bulk waves. The analysis results show that this virtual wave always propagates along the boundary for any incident angle and can be treated as a pseudo surface wave. The energy transmission analysis reveals that this surface wave transmits zero energy and does not violate the energy conservation between the incident and the reflected elastic bulk waves. In addition, the analysis also reveals an interesting result that the quasi-transverse, not the quasi-longitudinal, incident wave will be fully reflected and no quasi-longitudinal reflected wave will be generated if the incident angle is beyond a critical angle.
ANALYSIS OF SIGNAL TREND BY A PSEUDO-EMD METHOD WITH APPLICATIONS TO WEATHER AND SPEECH DATA
Authors: BHUIYAN SHARIF M. A. , CAREY SHERELL , KHAN JESMIN F.
Published: June 2013

Empirical mode decomposition (EMD) has been established as a valuable tool in determining nonlinear signal trend. EMD decomposes a one-dimensional (1D) signal into hierarchical components known as intrinsic mode functions (IMFs) and a residue, based on the local properties of the signal. The first IMF depicts the highest local oscillations, while the residue depicts the trend of a signal/data. In each iteration of the EMD process, interpolation is applied to some local maxima and minima points to form upper and lower envelopes, respectively. But, the application of interpolation methods causes huge computation time and other artifacts in the decomposition, which limits the use of EMD for many real life signals. This paper proposes an effective method that replaces the interpolation step by direct envelope estimation using order statistics filters, which results in decreased computation time, following a similar EMD approach that has been recently proposed for two-dimensional data or image analysis. The modified EMD of this paper called pseudo EMD (P-EMD) method is particularly useful in determining, analyzing, and/or modifying the trend of various signals to obtain and/or produce some desired results/outcomes. Several synthetic and real-life signals such as speech signal and sea level pressure and temperature are tested to verify the effectiveness of the P-EMD. From the results, P-EMD has been found as a superior alternative for trend analysis of signal/data, since it results in more accurate trend compared to the other interpolation based EMD methods such as classical EMD (CEMD) and a modified EMD (MEMD), and also facilitates faster computation.
ON INVESTIGATING EMD PARAMETERS TO SEARCH FOR GRAVITATIONAL WAVES
Authors: TAKAHASHI HIROTAKA , OOHARA KEN-ICHI , KANEYAMA MASATO , HIRANUMA YUTA , CAMP JORDAN B.
Published: June 2013

The Hilbert–Huang transform (HHT) is a novel, adaptive approach to time series analysis. It does not impose a basis set on the data or otherwise make assumptions about the data form, and so the time-frequency decomposition is not limited by spreading due to uncertainty. Because of the high resolution of the time-frequency, we investigate the possibility of the application of the HHT to the search for gravitational waves. It is necessary to determine some parameters in the empirical mode decomposition (EMD), which is a component of the HHT, and in this paper we propose and demonstrate a method to determine the optimal values of the parameters to use in the search for gravitational waves.
Transient Receptor Potential Channels and Mechanosensation
Authors: Eijkelkamp Niels , Quick Kathryn , Wood John N.
Published: June 2013

Transient receptor potential (TRP) channels act as sensors for a range of stimuli as diverse as light, sound, touch, pheromones, and tissue damage. Their role in mechanosensation in the animal kingdom, identified by gene ablation studies, has raised questions about whether they are directly mechanically gated, whether they act alone or in concert with other channels to transduce mechanical stimuli, and their relative importance in various functions and disease states in humans. The ability of these channels to form heteromultimers and interact with other ion channels underlies a range of cell-specific functions in different cell types. Here we overview recent advances in this rapidly expanding field, focusing on somatosensation, hearing, the cardiovascular system, and interactions between TRP channels and other proteins involved in mechanoelectrical signaling.
Psychological Research on Retirement
Authors: Wang Mo , Shi Junqi
Published: June 2013

Retirement as a research topic has become increasingly prominent in the psychology literature. This article provides a review of both theoretical development and empirical findings in this literature in the past two decades. We first discuss psychological conceptualizations of retirement and empirical operationalizations of retirement status. We then review three psychological models for understanding the retirement process and associated antecedents and outcomes, including the temporal process model of retirement, the multilevel model of retirement, and the resource-based dynamic model for retirement adjustment. We next survey the empirical findings regarding how various individual attributes, job and organizational factors, family factors, and socioeconomic context are related to the retirement process. We also discuss outcomes associated with retirement in terms of retirees' financial well-being, physical well-being, and psychological well-being.
Via Filling Electrodeposotion of 4μm Diameter Via by Periodical Reverse Current
Authors: Hayashi Taro , Kondo K. , Takeuchi Minoru , Saito Takeyasu , Okamoto Naoki , Bunya Masaru , Yokoi Masayuki
Published: June 2013

To enable low power consumption and the access speed increase,three dimensional packaging of semiconductor chips has beenproposed. In particular, a high-aspect ratio through silicon via(TSV)allows short chip to chip interconnection. 4 μm diameter and aspectratio of 7.5 via TSV has filled. The perfect via filling was achievedwithin 25 minutes with the increasing irev/|ion| ratios of periodicreverse pulse current waveform. In addition, we evaluatedproduced cuprous ion concentration during electrodeposition byusing rotating ring disk electrode(RRDE). From theelectrochemical measurement by RRDE, cuprous ion concentrationon the reactive surface was markedly increasing with theincreasing irev/|ion| ratios. At irev/|ion| ratio of large(irev/|ion| = 6.0), alarge amount of cuprous ion concentration produces during copperdissolution by reverse current and cuprous ion remain at the viabottom. High cuprous ion concentration at the via bottomaccelerate deposition at the via bottom and achieve bottom upfilling.
Stability of Glassy Ta-Rh Diffusion Barriers for Cu Metallization
Authors: Dalili Neda , Liu Qi , Ivey Douglas G.
Published: June 2013

Amorphous Ta-Rh thin films were studied as diffusion barriers for Cu metallization. Thermodynamic calculations were performed to predict the glass forming ability of the Ta-Rh system. Various compositions were deposited by co-sputtering from two targets and the theoretically predicted amorphization range was confirmed by structural characterization using XRD and TEM observations. These calculations provide a useful guide for selecting a glass forming composition suitable for diffusion barrier applications for Cu metallization. The selected composition was studied as a diffusion barrier in contact with Cu and Si. A 13 nm-thick Ta0.45Rh0.55 film is effective at temperatures up to 550°C, whereupon it dissociates into its constituents followed by formation of RhSi.
A New Concept for Spatially-Divided Reactive Ion Etching with ALD-Based Passivation
Authors: Roozeboom F. , Kniknie Bas , Lankhorst A. M. , Winands G. , Knaapen Raymond , Smets Mireille , Poodt Paul , Dingemans Gijs , Keuning Wytze , Kessels W.M.M.
Published: June 2013

Conventional Deep Reactive Ion Etching (DRIE) is a plasma etch process with alternating half-cycles of 1) Si-etching with SF6 to form gaseous SiFx etch products, and 2) passivation with C4F8 polymerizing as a protecting fluorocarbon deposit on the sidewalls and bottom of the etched features. We report on a novel alternative and disruptive technology concept of Spatially-divided Deep Reactive Ion Etching, where the process is converted from the time-divided into the spatially divided regime. The spatial division can be accomplished by ~20 to 100 μm high inert gas-bearing ‘curtains’ that confine the reactive gases to individual (often linear) injection slots constructed in a gas injector head. By horizontally moving the substrate back and forth under the head one can realize the alternate exposures to compose the overall cycle.Next improvement in the spatially-divided approach is the replacement of the CVD-based C4F8 passivation steps by ALD-based oxide (e.g. SiO2) deposition cycles. The method can have industrial potential in cost-effective creation of advanced 3D TSV interconnects and MEMS, but also in advanced patterning of, e.g., nanoscale FinFET devices with reduced line edge roughness, thus approaching Atomic Layer Etching accuracy.