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We developed a formate-removing methanogenic inoculum (FRI) to facilitate succinate production from crude glycerol by Escherichia coli. FRI converted formate to methane, thereby enabling glycerol fermentation without additional electron acceptors under neutral pH. FRI was selectively enriched from sludge from the anaerobic digester of the Seonam sewage treatment plant (Seoul); this process was assessed via Illumina sequencing and scanning electron microscopy imaging. Methanobacterium congolense species occupied only 0.3% of the archaea community in the sludge and was enriched to 99.5% in complete FRI, wherein succinate-degrading bacteria were successfully eliminated. Co-culture with FRI improved glycerol fermentation and yielded 7.3 mM succinate from 28.7 mM crude glycerol, whereby FRI completely converted formate into methane. This study is the first to demonstrate methane production by M. congolense species, using formate. M. congolense-dominated FRI can serve as a renewable facilitator of waste feedstock fermentation and enable the production of commercially important compounds.

Purpose The cyclin-dependent kinase 1 (Cdk1) and cyclin B complex performs important roles in the transition from the G2 to M phase in the cell cycle through removal of inhibitory phosphates on Cdk1, and Cdc25B, which is a dual-specific phosphatase, mediates these dephosphorylation events. However, measuring Cdc25B activity by existing methods is hampered by inadequate nonspecific substrates and the need to use a radiolabeled isotope. The present study aimed to develop an improved method with which to properly measure Cdc25B activity using a novel nonradioisotopic assay and Cdc25B overexpression cell lines. Materials and methods A nonradioisotopic Cdk1 kinase assay, based on Western blotting for retinoblastoma protein and histone H1, was used to analyze Cdc25B activity. Also, stable Cdc25B2 and Cdc25B3 overexpression HeLa cell lines were constructed using the tetracycline-regulated expression system and were applied as a tool for screening for inhibitors of Cdc25B. Results The present study developed and optimized a nonradioisotopic assay method to properly measure Cdc25B activity. Furthermore, we constructed stable Cdc25B2 and Cdc25B3 overexpression HeLa cell lines for the establishment of a strong assay system with which to evaluate the specificity of Cdc25B inhibitors under conditions similar to the intracellular environment. These methods were confirmed as useful tools for measuring Cdc25B activity. Conclusion The nonradioisotopic Cdk1 kinase assay and Cdc25B overexpression cell lines developed in this study can be conveniently used as tools for screening inhibitors of Cdc25B phosphatase as anticancer drugs.

Recently, antibody fragments have been studied as therapeutic agents because they lack Fc effector function while having affinity similar to their original monoclonal antibody and can be produced using E. coli. Antibody fragments can be purified using affinity chromatography in the capture step, although they need a polishing step because of product-related impurities, mainly charge variants. Unlike monoclonal antibodies, few studies exist regarding the separation of charge variants in antibody variants. In this study, an efficient separation of charge variant method was assessed using a cation exchange chromatography resin with salt and a pH gradient. The SP ImpRes resin and pH gradient exhibited the most effective separation potency using combinations of resin and the separation method. The antibody fragment that did not undergo the charge variant separation process exhibited a difference in the tertiary structure of the protein and in vivo pharmacokinetics. However, the antibody fragment was similar to the reference protein when the charge variant separation process was performed. These results are expected to support efficient charge variant separation of antibody fragments and to be applied to the industrial production of therapeutic antibody fragments.

This paper explores the probable causes and consequences of an Asian Paradox or the highly incongruous structure of Asia within the broader international system: at once the engine of global economic growth while at the same time, the repository of all of the world's outstanding security threats and challenges. Asia in the 21st century is going to be a key test bed of the commercial peace theory and whether the U.S.-China strategic rivalry will result in some type of a conflict. Attention is also paid to the potential consequences flowing from the end of Asia's Meiji era or when all of Asia's major powers and key middle powers have achieved or are well on their way of achieving what Japan accomplished by the late 1890s: a wealthy economy and a strong military. How an increasingly wealthy, technologically advanced, and a militarily sophisticated Asia decides to cope with numerous security dilemmas is Asia's new Long March including the extent to which the region's strategically consequential states...

Real-life, out-of-laboratory, measurements of pedestrian walking dynamics allow extensive and fully-resolved statistical analyses. However, data acquisition in real-life is subjected to the randomness and heterogeneity that characterizes crowd flows over time. In a typical real-life location, disparate flow conditions follow one another in random order: for instance, a low density pedestrian co-flow dynamics may suddenly turn into a high density counter-flow scenario and then back again. Isolating occurrences of similar flow conditions within the acquired data is a paramount first step in the analyses in order to avoid spurious statistics and to enable qualitative comparisons.In this paper we extend our previous investigation on the asymmetric pedestrian dynamics on a staircase landing, where we collected a large statistical database of measurements from ad hoc continuous recordings. This contribution has a two-fold aim: first, method-wise, we discuss an analysis workflow to consider large-scale experimental measurements, suggesting two querying approaches to automatically extract occurrences of similar flow scenarios out of datasets. These pursue aggregation of similar scenarios on either a frame or a trajectory basis. Second, we employ these two different perspectives to further explore asymmetries in the pedestrian dynamics in our measurement site. We report cross-comparisons of statistics of pedestrian positions, velocities and accelerations vs. flow conditions as well as vs. querying approach.

In this work we study pedestrian-pedestrian interactions from observational experimental data in diluted pedestrian crowds. While in motion, pedestrians continuously adapt their walking paths trying to preserve mutual comfort distances and to avoid collisions. Leveraging on a high-quality, high-statistics data set, composed of several few millions real-life trajectories acquired from state-of-the-art observational experiments (about 6 months of high-resolution pedestrian tracks acquired in a train station), we develop a quantitative model capable of addressing interactions in the case of binary collision avoidance. We model interactions in terms of both long-range (sight based) and short-range (hard-contact avoidance) forces, which we superimpose on our Langevin model for noninteracting pedestrian motion [Corbetta, Phys. Rev. E 95, 032316 (2017)2470-004510.1103/PhysRevE.95.032316] (here further tested and extended). The model that we propose here features a Langevin dynamics with fast random velocity fluctuations that are superimposed on the slow dynamics of a hidden model variable: the intended walking path. In the case of interactions, social forces may act both on the intended path and on the actual walked path. The model is capable of reproducing quantitatively relevant statistics of the collision avoidance motion, such as the statistics of the side displacement and of the passing speed. Rare occurrences of actual bumping events are also recovered. Furthermore, comparing with large data sets of real-life tracks involves an additional computational challenge so far neglected: identifying automatically, within a database containing very heterogeneous conditions, only the relevant events corresponding to binary avoidance interactions. In order to tackle this challenge, we propose a general approach based on a graph representation of pedestrian trajectories, which allows us to effectively operate complexity reduction for efficient data classification and selection.

Escherichia coli has been a primary host for the prokaryotic production of antibody fragments (Fabs) and has contributed to several successes in the pharmaceutical industry. Nevertheless, the requirement of disulfide bonds often results in low-yield fermentation and a lack of cost-effectiveness. Despite the improved production of functional Fabs by fermentation below 30 °C, the limited cellular growth needs further work. To address these issues, we investigated the effect of nitrogen supply on the cellular growth and the Fab productivity. We used the anti-human VEGF-A Fab as a model that exhibited poor expression at 37 °C regardless of the amount of nitrogen supplied during fermentation. In stark contrast, the expression yield of soluble Fab with a gross nitrogen supply of 6.91 g/L of broth throughout the fermentation at 25 °C was 332 mg/L. Furthermore, and increased nitrogen supply of 10.9 g/L significantly improved the yield of active form by 59.7% and the cellular growth rate by 39.3%. These results indicate that overdosing of a nitrogen source at low temperature is critical to Fab productivity in E. coli.

Understanding and modeling the dynamics of pedestrian crowds can help with designing and increasing the safety of civil facilities. A key feature of crowds is its intrinsic stochasticity, appearing even under very diluted conditions, due to the variability in individual behaviours. Individual stochasticity becomes even more important under densely crowded conditions, since it can be nonlinearly magnified and may lead to potentially dangerous collective behaviours. To understand quantitatively crowd stochasticity, we study the real-life dynamics of a large ensemble of pedestrians walking undisturbed, and we perform a statistical analysis of the fully-resolved pedestrian trajectories obtained by a year-long high-resolution measurement campaign. Our measurements have been carried out in a corridor of the Eindhoven University of Technology via a combination of Microsoft Kinect 3D-range sensor and automatic head-tracking algorithms. The temporal homogeneity of our large database of trajectories allows us to robustly define and separate average walking behaviours from fluctuations parallel and orthogonal with respect to the average walking path. Fluctuations include rare events when individuals suddenly change their minds and invert their walking direction. Such tendency to invert direction has been poorly studied so far even if it may have important implications on the functioning and safety of facilities. We propose a novel model for the dynamics of undisturbed pedestrians, based on stochastic differential equations, that provides a good agreement with our experimental observations, including the occurrence of rare events.

We discuss the regular transonic shock reflections for a model problem of multidimensional conservation laws, the nonlinear wave system. We consider two incident shocks that create reflected shocks, and the state behind the reflected shocks becomes subsonic. We present the existence of the global solution to this configuration, and provide an analysis to handle a degeneracy occurred in the problem and Lipschitz estimates near the sonic boundary. We further implement Lax–Liu positive schemes and Strang splitting, and obtain linear correlations of the incident shock strength and the reflected shock strength. The result obtained in this paper develops a mathematical theory of transonic shock reflection problems. Furthermore the numerical result provides better understanding of the solution structure. This paper provides an application of an important physical problem.

We discuss numerical results for two dimensional Riemann problems for the nonlinear wave system. We consider four sectorial Riemann data and present the numerical results for two configurations. The first configuration is that incident shocks create reflected shocks, and the state behind the reflected shocks becomes subsonic. The second configuration is an interaction between two transonic shocks; one is created by an interaction with the sonic circle, and the other is created by the shock reflection. We implement Lax–Liu positive schemes and Strang splitting, and obtain linear correlations of the incident shock strength and the reflected shock strength for the first configuration. Furthermore we present intriguing numerical results on interactions of two transonic shocks for the second configuration.

We investigate via extensive experimental data the dynamics of pedestrians walking in a corridor-shaped landing in a building at Eindhoven University of Technology. With year-long automatic measurements employing a Microsoft KinectTM 3D-range sensor and ad hoc tracking techniques, we acquired few hundreds of thousands pedestrian trajectories in real-life conditions. Here we discuss the asymmetric features of the dynamics in the two walking directions with respect to the flights of stairs (i.e. ascending or descending). We provide a detailed analysis of position and speed fields for the cases of pedestrians walking alone undisturbed and for couple of pedestrians in counter-flow. Then, we show average walking velocities exploring all the observed combinations in terms of numbers of pedestrians and walking directions.

We present numerical results on self-similar two-dimensional Riemann problems governed by the compressible Euler system and the nonlinear wave system, which give rise to a transonic shock. We consider a configuration for a vertical incident shock moving to the right above a rectangular object. The incident shock then interacts with a sonic circle soon after it moves beyond the object, and creates a transonic region. We implement Lax–Liu positive schemes and Strang splitting, and obtain linear correlations of the incident shock strength and the shock strength at the vertical wall. We further implement Roe average methods and finite volume methods on quadrilateral grids to capture a contact discontinuity of the Euler system near the corner of the object. The contact discontinuity creates a new supersonic state and a transonic shock inside the transonic region.

We present numerical results on a two-dimensional Riemann problem governed by the self-similar nonlinear wave system that gives rise to a transonic shock. We consider a configuration for a vertical incident shock moving to the right above a rectangular object. The incident shock then interacts with a sonic circle soon after it moves beyond the object, and creates a transonic region. We implement Lax–Liu positive schemes and Strang splitting, and obtain several numerical solutions for the model system. With the numerical results that we have obtained, we present several analyses of the transonic shock strengths and the positions of the transonic shocks with various Riemann data. Moreover, due to the presence of the corner of the object, numerical oscillations are apparent. We discuss regularity results for the solution near the corner of the object. Copyright © 2010 John Wiley & Sons, Ltd.

Glycosylation of the hemagglutinin (HA) and neuraminidase (NA) of the influenza provides crucial means for immune evasion and viral fitness in a host population. However, the time-dependent dynamics of each glycosylation sites have not been addressed. We monitored the potential N-linked glycosylation (NLG) sites of over 10,000 HA and NA of H1N1 subtype isolated from human, avian, and swine species over the past century. The results show a shift in glycosylation sites as a hallmark of 1918 and 2009 pandemics, and also for the 1976 “abortive pandemic”. Co-segregation of particular glycosylation sites was identified as a characteristic of zoonotic transmission from animal reservoirs, and interestingly, of “reverse zoonosis” of human viruses into swine populations as well. After the 2009 pandemic, recent isolates accrued glycosylation at canonical sites in HA, reflecting gradual seasonal adaptation, and a novel glycosylation in NA as an independent signature for adaptation among humans. Structural predictions indicated a remarkably pleiotropic influence of glycans on multiple HA epitopes for immune evasion, without sacrificing the receptor binding of HA or the activity of NA. The results provided the rationale for establishing the ecological niche of influenza viruses among the reservoir and could be implemented for influenza surveillance and improving pandemic preparedness.

Is North Korea ready and willing to give up its nuclear weapons? Proponents of arms control and sustained engagement with North Korea maintain that Pyongyang's desire to acquire nuclear weapons stemmed from ingrained insecurity vis-a-vis the United States or more specifically, the threat that the US poses to fundamental regime security. However, the primordial source of Kim Jong Il's existential insecurity stems largely from the abnormal, structural idiosyncracies of his regime and not, as many naively believe, the hardline policies of the Bush administration. Accordingly, the Kim Jong Il regime's fundamental dilemma boils down to the fact that the domestic political costs of giving up its nuclear capabilities are just as high as the costs of retaining them. Debunking the myth that the US, rather than North Korea, poses the greater challenge to South Korean security is as important as ensuring that North Korea dismantles its nuclear arsenal.

The dynamics of inertial particles in turbulence is modelled and investigated by means of direct numerical simulation of an axisymmetrically expanding homogeneous turbulent strained flow. This flow can mimic the dynamics of particles close to stagnation points. The influence of mean straining flow is explored by varying the dimensionless strain rate parameter $Sk_{0}/{\it\epsilon}_{0}$ from 0.2 to 20, where $S$ is the mean strain rate, $k_{0}$ and ${\it\epsilon}_{0}$ are the turbulent kinetic energy and energy dissipation rate at the onset of straining. We report results relative to the acceleration variances and probability density functions for both passive and inertial particles. A high mean strain is found to have a significant effect on the acceleration variance both directly by an increase in the frequency of the turbulence and indirectly through the coupling of the fluctuating velocity and the mean flow field. The influence of the strain on the normalized particle acceleration probability distribution functions is more subtle. For the case of a passive particle we can approximate the acceleration variance with the aid of rapid-distortion theory and obtain good agreement with simulation data. For the case of inertial particles we can write a formal expression for the accelerations. The magnitude changes in the inertial particle acceleration variance and the effect on the probability density function are then discussed in a wider context for comparable flows, where the effects of the mean flow geometry and of the anisotropy at small scales are present.

A class of degenerate elliptic PDEs is considered. Specifically, it is assumed that the diffusion coefficient vanishes on the boundary of the domain. It is shown that if the diffusion coefficient vanishes fast enough, then the problem has a unique solution in the class of smooth functions even if no boundary conditions are supplied. A numerical method is derived to compute solutions for such degenerate equations. The problem is motivated by a certain approach to the recovery of the phase of a wave from intensity measurements.

The problem of phase reconstruction from intensity is considered in the paraxial geometrical optics regime. The data consist of intensity measurements on two planes orthogonal to the direction of propagation. A new variational principle is used to find the ray mapping between the planes. The mapping is found by minimizing an appropriate function. The minimization process involves a nonlinear partial differential equation. A numerical algorithm for solving this equation is described. The phase is then integrated from the ray mapping. Finally, the method and code are examined by applying them to simulated data.

(2004). Rethinking future paths on the Korean Peninsula. The Pacific Review: Vol. 17, No. 2, pp. 249-270.

Changing political attitudes in South Korea, and the appearance of some divergence of view between Washington and Seoul on the nature of the threat posed by North Korea are impelling a re-examination of the US-South Korea alliance. At the same time, although still concerned with deterring an invasion from Pyongyang, the alliance must now also deal with the possible conse quences of a catastrophic collapse of the North Korean state. Changing threat perceptions, developments in military technology and doctrine associated with the 'revolution in military affairs', as well as the emergence of new issues such as terrorism, all require a redefinition of the alliance. While the changing geo-strategic environment and the wider regional role of the alliance will all be factors in the modifications made to the Washington-Seoul security relationship, the key to South Korea's future alliance choices will be the nature of the path taken to eventual Korean unification.

In sharp contrast to land-dominant forces with only limited technological capabilities, key armed forces such as the PRC's People's Liberation Army (PLA), Japan's Self Defense Forces (SDF), and the South and North Korean militaries have built up significant power projection capabilities since the 1980s. North Korea's weapons of mass destruction (WMD) programs and assets (including a potential nuclear weapons capability) have surfaced as key security concerns since the early 1990s and for its part, China has begun to implement its own revolution in military affairs (RMA) strategies that may enable the PRC to have very robust power projection capabilities by 2020 or 2030. If one includes Indian and Pakistani nuclear weapons programs into the broader strategic equation, Asia may well face an increasingly volatile arms race over the next 20–30 years. Seen within this context, the role of air power is likely to assume growing importance in East Asia's projected force modernization programs, given the ...

Analysts remain sharply divided on the underlying motivations behind North Korea's ballistic missile program, more than two years after Pyongyang startled the world by test firing its Taepodong-1 missile in August 1998. In the aftermath of the historic South-North summit meeting in June and US Secretary of State Madeline Albright's path-breaking trip to Pyongyang in October, proponents of the engagement school argue that with a mixture of patience and inducements, North Korea will ultimately negotiate away its missiles. They point to the 1994 Agreed Framework as a key reminder that North Korea uses its weapons of mass destruction capability as a bargaining chip. Conversely, countervailing arguments point out that North Korea's ballistic missile program serves multiple purposes such as shifting the correlation of forces to its favor, supporting the military's modernization goals, and as the primary symbol of military prowess and that, as a result, a negotiated settlement is unlikely. This paper assesses No...

The future of European and Asian security can no longer be separated owing to pervasive globalization, the rise of East Asia as a new geopolitical hub, and the increasing web of interests that binds the United States, the European Union (EU), and East Asia together. Of the three key relationships‐the transatlantic, the transpacific, and the Eurasian‐the latter remains the weakest owing to a combination of historical, political, and economic reasons. Improving this relationship from the strategic, economic, and conceptual dimensions will bring significant dividends to the two regions. Operationalizing this challenge, however, is going to be cumbersome and time consuming given the historical lack of strategic interaction between East Asia and Europe.

An iterative phase-shifting algorithm based on the least-squares principle is developed to overcome the random piston and tilt wavefront errors generated from the phase shifter. The algorithm iteratively calculates the phase distribution and the phase-shifting map to minimize the sum of squared errors in the interferograms. The performance of the algorithm is evaluated via computer simulations and validated by the Fizeau interferometer measurements. The results show that the proposed algorithm has a fast convergence rate and satisfactory phase-estimation accuracy, improving the measurement precision of the phase-shifting interferometers with significant phase-shifter errors.

Multipolar East Asia and Implications for Regional and Korean Security by Chung Min Lee Despite recent encouraging developments such as economic growth, démocratisation and reconciliations in Asia, difficulties loom ahead. Weapons procurement, notably of ballistic missiles, and the modernisation of defence capabilities are particularly apparent in the region. They are linked both to prosperity, as well as to concerns about China and about nuclear proliferation (for instance in India, Pakistan and North Korea). In spite of an assertive atitude, American non-proliferation means seem limited. Washington thus veered towards a more conciliatory approach to North Korea, which has been of some concern to Seoul. Some doubt has been cast over the credibility of the US commitment to South Korea's security including by means of nuclear weapons in case of North Korean attack. The end of the cold war has not fundamentally changed the Korean peninsula's dilemma. Reunification seems inevitable in the future, depending on political changes in the North., En Asie, derrière les phénomènes récents encourageants (croissance, démocratisation et réconciliations) se profilent de nouvelles difficultés. Les acquisitions d'armes, en particulier de missiles balistiques, et la modernisation des appareils de défense sont manifestes dans la région. Elles sont liées à la prospérité et aux perceptions de menaces émanant de la Chine et de la prolifération des armements, notamment nucléaires (Inde, Pakistan et Corée du Nord). Malgré un discours offensif, les moyens de lutte américains en la matière apparaissent limités. Ainsi, envers Pyongyang, Washington est passé d'une position « musclée » à une posture plus conciliante, ce qui n'a pas manqué d'inquiéter Séoul. La fermeté de l'engagement américain, notamment à utiliser l'arme nucléaire en cas d'attaque du Nord, ne semble désormais plus assurée. La fin de la guerre froide n'a pas fondamentalement modifié la donne coréenne, toutefois la perspective de réunification apparaît inévitable à terme, conditionnée par des changements politiques au Nord., Lee Chung Min. Multipolarité et prolifération en Extrême-Orient : implications pour la sécurité régionale et coréenne. In: Politique étrangère, n°3 - 1995 - 60ᵉannée. pp. 659-670.

Part 1: The Northeast Asian Security Complex 1. The Northeast Asian Security Complex: History, Power, and Strategic Choices Chung Min Lee and T.J. Pempel 2. The Requirements for Security Cooperation in Northeast Asia: Theory and Reality Ajin Choi Part 2: Security Challenges, Drivers, and Issues 3. Nuclear Weapons, State Bellicosity, and Prospects for an East Asian Security Architecture Joseph M. Grieco 4. Between Multilateralism and Bilateralism Geunwook Lee Part 3: State Interests and Strategies 5. European Experience and Lessons Hae-Won Jun 6. China's Strategic Option: Multilateralism and the Pursuit of Influence Sukhee Han and Luo Jianbo 7. What is a `Liberal' East Asia Policy? Japan and the DPJ Government Yoko Iwama 8. ROK: Toward Peace and Cooperation Hyung Min Kim 9. Leadership and Commitment: The United States, Its Allies, and Emerging Security Institutions in Northeast Asia Carol Atkinson and Giacomo Chiozza Part 4: Actualizing Security Cooperation and Its Future 10. The Northeast Asia Cooperation Dialogue: An Experiment in Track II Multilateral Diplomacy Susan L. Shirk 11. Conclusion T.J. Pempel

A subaperture stitching algorithm was developed for testing aspheric surfaces. The full aperture was divided into one central circular region plus several partially-overlapping annuli. Each annulus was composed of partially-overlapping circular subapertures. The phase map in each subaperture was obtained through the phase-shifting interferometry and retrieved by an iterative tilt-immune phase-shifting algorithm and a Zernike-polynomial-based phase-unwrapping process. All subapertures in one annulus were stitched simultaneously in least-squares sense. By eliminating the relative piston and tilt between adjacent subapertures, the sum of squared errors in the overlapped regions was minimized. The phase stitching between annuli also utilized the least-squares method in the overlapped region. Simulation results on a test wavefront with 30-wave spherical aberrations demonstrated the effectiveness of the proposed algorithm. The rms phase residue after the phase-shifting, phase-unwrapping and phase-stitching processes was 0.006 waves, which met the precision requirement of common interferometers. This algorithm should be applicable to general surfaces in subaperture stitching interferometry.

An iterative least-squares-based phase-shifting algorithm was developed to cope with random pistons and tilts from the phase shifter. The allowable tilt amount was 0.5 waves over the pupil. The achieved rms accuracy was 0.0024 radians.

A human influenza A virus X-31 (high-yielding strain) was cold-adapted for possible future use as live attenuated vaccine. Mutant influenza viruses were selected during successive serial passage in embryonated hens' eggs at progressively lower sub-optimal temperature (30, 27 degrees C followed by 24 degrees C). The cold-passaged mutant exhibited both temperature-sensitivity (ts) and cold-adapted (ca) phenotypes. The pathogenicity and immunogenicity of X-31 ca virus were studied in mice following intranasal inoculation. The mice did not show clinical signs even at high titer infection. Immunization of mice with X-31 ca virus elicited high titers of neutralizing antibody and provided complete protection against homologous and heterologous virus challenges. To assess the genetic stability, the X-31 ca virus was passaged at 37 degrees C in MDCK cells or inoculated into mice. Revertant virus was not found in the lungs of any of the mice and the supernatants of the MDCK culture. We conclude that the X-31 ca candidate vaccine virus exhibits the desired level of attenuation, immunogenicity, and protective efficacy required for live attenuated vaccine and merits further evaluation at clinical level.

We studied the in-and the out-coupling efficiencies of photons with a thin InGaAs slab covered by periodic gold nano-slit arrays, by measuring transmission and photoluminescence (PL) spectra. While the maximum in-coupled photons into the InGaAs slab waveguide were found at dip positions in transmission spectra, the mostly out-coupled photons were observed as peaks in PL spectra. For different periods of slit arrays and incident angles we discussed spectral positions of transmission dips and efficiency of the in-coupling influenced by the absorption coefficient of InGaAs. In PL spectra we measured overall enhanced PL intensities from the InGaAs slab covered by slit arrays compared to that of a bare InGaAs, where the peak positions are determined by the period of slit arrays as well. Our findings are important for designing semiconductors both as an optically passive waveguide and active light emitter. (C) 2012 Optical Society of America

We present results from direct numerical simulations of strained turbulent flows. Our focus is twofold. One is to improve our understanding of the interactions of large and small scale dynamics in strained turbulent flow; another focus is to understand the influence of the straining on the motions of passive and inertial particles of varied Stokes numbers. We seek to emphasize the effects of the strain geometry and strain rate on the particles' behaviors. Eulerian flow field results and the Lagrangian particle velocity and acceleration statistics will be discussed. The Rogallo algorithm is applied for simulating the flow field in a non-cubical domain.

Purpose : To evaluate the geometry of carotid artery by assessing the images of contrast-enhanced MR angiography (CE-MRA) and interrelationships between the geometry of carotid artery and clinical factors. Materials and Methods : 216 consecutive patients who performed supraaortic CE-MRA with fast spoiled gradient-echo imaging were included. Their medical records were reviewed for variable information including risk factors predictive of generalized atherosclerotic disease (age, hypertension (HTN), diabetes mellitus, hyperlipidema, and smoking), sex, body weight, height, and body mass index (BMI). We reviewed the CE-MRA with carotid origin (3 types), carotid artery tortuosity, angle of internal carotid artery bifurcation, the type of aortic arch branching, and the presence of the coiling of carotid artery. Results : Multinomial logistic regression analysis showed that significantly contributed clinical backgrounds for carotid origin were the age and the BMI. With an increase of age at 1, the probability that the type of carotid origin become from type 1 to type 2 was 0.9 times (p=0.004) in right carotid artery (RCA), 0.9 times (p = 0.031) in left carotid artery (LCA), 0.9 times that are likely to be type3 from type 2 (pand , respectively. Conclusion : The BMI, age, sex and presence of HTN affects the geometry of carotid arteries, the site of origin and tortuosity of carotid artery specifically.