bluuebunny/crossref_metadata_2025 huggingface dataset:
Harnessing Third Parties for Transnational Environmental Crime Prevention
Authors: Ayling Julie
Published: September 2013

Because transnational environmental crime (TEC) can result in the demise of an environmental resource or irreversible damage to the environment and has implications for national and global security, its prevention is a critical issue. Deterrence through law enforcement can go only a limited distance towards preventing TEC. However, there is a huge potential for third parties to be active participants, alongside governmental authorities, in crafting and implementing strategies for TEC prevention. This article explores the ways in which states can catalyze third parties – non-state, non-offending actors – to contribute their own capacities towards the pursuit of preventive outcomes. It draws together concepts and theories from policing studies, criminology and regulatory studies to highlight changing relationships between the state and non-state actors with respect to crime control, and applies them to TEC. Examples and illustrations used in the article relate mainly to efforts to combat the illegal wildlife trade. The article concludes that a more systematic approach to TEC prevention involving third parties is needed, and that this requires dedicated strategic analysis and planning on the part of states, working individually and together.
A Smile Radiates Outwards and Biases the Eye Expression
Authors: Fernández-Martín Andrés , Gutiérrez-García Aida , Calvo Manuel G.
Published: September 2013

This study investigated how extrafoveally seen smiles influence the viewers’ perception of non-happy eyes in a face. A smiling mouth appeared in composite faces with incongruent (angry, fearful, neutral, etc.) eyes, thus producing blended expressions, or they appeared in intact faces with genuine expressions. Overt attention to the eye region was spatially cued, foveal vision of the mouth was blocked by gaze-contingent masking, and the distance between the eyes and the mouth was varied. Participants evaluated whether the eyes were happy or not. Results indicated that the same non-happy eyes were more likely to be judged as happy, and more slowly to be judged as not happy, in presence more than in absence of a smile. As (a) the smiling mouth was highly salient regardless of type of eyes, (b) the influence on the eyes increased gradually as a function of eye-mouth proximity, and (c) the effect occurred in the absence of fixations on the mouth, we conclude that a salient smile radiates outwards to other face regions through a projection mechanism, thus making the eye expression look happy.
Array Effects, Spatial Concepts, or Information Processing Speed
Authors: Lange-Küttner Christiane
Published: September 2013

A reaction time/accuracy experiment investigated the development of visual memory for object shape and location in 6–7- and 8–9-year-old children and adults (N = 72) in three array types: (1) an empty screen, (2) a frame delineating a region, and (3) a grid with individually delineated places. A maximized learning design was used. Explicit array boundaries in the frame and in the grid facilitated place memory in both children and adults, while place memory in the empty screen was less correct, slower, and did not improve. Children’s visual memory was initially low, but learning during the task resulted in better object than place memory. Like the children at the end of the session, adults showed better object than place memory at the beginning of the task. They subsequently also improved their object memory, but doubled their place memory performance. Children with object-region binding showed better place memory and more systematic learning effects that were specific to arrays. However, neither array boundaries nor spatial binding concepts explained the absence of place learning in children. Instead, children tried to prevent proactive shape interference in the repeated memory sets at the cost of place learning, while adults did not.
Gender-Related Differential Item Functioning in Vocational Interest Measurement
Authors: Wetzel Eunike , Hell Benedikt
Published: September 2013

Large mean differences are consistently found in the vocational interests of men and women. These differences may be attributable to real differences in the underlying traits. However, they may also depend on the properties of the instrument being used. It is conceivable that, in addition to the intended dimension, items assess a second dimension that differentially influences responses by men and women. This question is addressed in the present study by analyzing a widely used German interest inventory (Allgemeiner Interessen-Struktur-Test, AIST-R) regarding differential item functioning (DIF) using a DIF estimate in the framework of item response theory. Furthermore, the impact of DIF at the scale level is investigated using differential test functioning (DTF) analyses. Several items on the AIST-R’s scales showed significant DIF, especially on the Realistic, Social, and Enterprising scales. Removal of DIF items reduced gender differences on the Realistic scale, though gender differences on the Investigative, Artistic, and Social scales remained practically unchanged. Thus, responses to some AIST-R items appear to be influenced by a secondary dimension apart from the interest domain the items were intended to measure.
Multiple-Capillary Measurement of RBC Speed, Flux, and Density with Optical Coherence Tomography
Authors: Lee Jonghwan , Wu Weicheng , Lesage Frederic , Boas David A
Published: September 2013

As capillaries exhibit heterogeneous and fluctuating dynamics even during baseline, a technique measuring red blood cell (RBC) speed and flux over many capillaries at the same time is needed. Here, we report that optical coherence tomography can capture individual RBC passage simultaneously over many capillaries located at different depths. Further, we demonstrate the ability to quantify RBC speed, flux, and linear density. This technique will provide a means to monitor microvascular flow dynamics over many capillaries at different depths at the same time.
Systems Pharmacology Models Can Be Used to Understand Complex Pharmacokinetic‐Pharmacodynamic Behavior: An Example Using 5‐Lipoxygenase Inhibitors
Authors: Demin O , Karelina T , Svetlichniy D , Metelkin E , Speshilov G , Demin O , Fairman D , van der Graaf PH , Agoram BM
Published: September 2013

Zileuton, a 5‐lipoxygenase (5LO) inhibitor, displays complex pharmaokinetic (PK)‐pharmacodynamic (PD) behavior. Available clinical data indicate a lack of dose–bronchodilatory response during initial treatment, with a dose response developing after ~1–2 weeks. We developed a quantitative systems pharmacology (QSP) model to understand the mechanism behind this phenomenon. The model described the release, maturation, and trafficking of eosinophils into the airways, leukotriene synthesis by the 5LO enzyme, leukotriene signaling and bronchodilation, and the PK of zileuton. The model provided a plausible explanation for the two‐phase bronchodilatory effect of zileuton–the short‐term bronchodilation was due to leukotriene inhibition and the long‐term bronchodilation was due to inflammatory cell infiltration blockade. The model also indicated that the theoretical maximum bronchodilation of both 5LO inhibition and leukotriene receptor blockade is likely similar. QSP modeling provided interesting insights into the effects of leukotriene modulation.

CPT: Pharmacometrics & Systems Pharmacology (2013) 2, e74; doi:10.1038/psp.2013.49; advance online publication 11 September 2013
A cross-species socio-emotional behaviour development revealed by a multivariate analysis
Authors: Koshiba Mamiko , Senoo Aya , Mimura Koki , Shirakawa Yuka , Karino Genta , Obara Saya , Ozawa Shinpei , Sekihara Hitomi , Fukushima Yuta , Ueda Toyotoshi , Kishino Hirohisa , Tanaka Toshihisa , Ishibashi Hidetoshi , Yamanouchi Hideo , Yui Kunio , Nakamura Shun
Published: September 2013

Recent progress in affective neuroscience and social neurobiology has been propelled by neuro-imaging technology and epigenetic approach in neurobiology of animal behaviour. However, quantitative measurements of socio-emotional development remains lacking, though sensory-motor development has been extensively studied in terms of digitised imaging analysis. Here, we developed a method for socio-emotional behaviour measurement that is based on the video recordings under well-defined social context using animal models with variously social sensory interaction during development. The behaviour features digitized from the video recordings were visualised in a multivariate statistic space using principal component analysis. The clustering of the behaviour parameters suggested the existence of species- and stage-specific as well as cross-species behaviour modules. These modules were used to characterise the behaviour of children with or without autism spectrum disorders (ASDs). We found that socio-emotional behaviour is highly dependent on social context and the cross-species behaviour modules may predict neurobiological basis of ASDs.
Reorientation of the first signal-anchor sequence during potassium channel biogenesis at the Sec61 complex
Authors: Watson Helen R. , Wunderley Lydia , Andreou Tereza , Warwicker Jim , High Stephen
Published: September 2013

The majority of the polytopic proteins that are synthesized at the ER (endoplasmic reticulum) are integrated co-translationally via the Sec61 translocon, which provides lateral access for their hydrophobic TMs (transmembrane regions) to the phospholipid bilayer. A prolonged association between TMs of the potassium channel subunit, TASK-1 [TWIK (tandem-pore weak inwardly rectifying potassium channel)-related acid-sensitive potassium channel 1], and the Sec61 complex suggests that the ER translocon co-ordinates the folding/assembly of the TMs present in the nascent chain. The N-terminus of both TASK-1 and Kcv (potassium channel protein of chlorella virus), another potassium channel subunit of viral origin, has access to the N-glycosylation machinery located in the ER lumen, indicating that the Sec61 complex can accommodate multiple arrangements/orientations of TMs within the nascent chain, both in vitro and in vivo. Hence the ER translocon can provide the ribosome-bound nascent chain with a dynamic environment in which it can explore a range of different conformations en route to its correct transmembrane topology and final native structure.
HEXIM1 down-regulates hypoxia-inducible factor-1α protein stability
Authors: Yeh I-Ju , Ogba Ndiya , Bensigner Heather , Welford Scott M. , Montano Monica M.
Published: September 2013

We have previously reported on the inhibition of HIF-1α (hypoxia-inducible factor α)-regulated pathways by HEXIM1 [HMBA (hexamethylene-bis-acetamide)-inducible protein 1]. Disruption of HEXIM1 activity in a knock-in mouse model expressing a mutant HEXIM1 protein resulted in increased susceptibility to the development of mammary tumours, partly by up-regulation of VEGF (vascular endothelial growth factor) expression, HIF-1α expression and aberrant vascularization. We now report on the mechanistic basis for HEXIM1 regulation of HIF-1α. We observed direct interaction between HIF-1α and HEXIM1, and HEXIM1 up-regulated hydroxylation of HIF-1α, resulting in the induction of the interaction of HIF-1α with pVHL (von Hippel–Lindau protein) and ubiquitination of HIF-1α. The up-regulation of hydroxylation involves HEXIM1-mediated induction of PHD3 (prolyl hydroxylase 3) expression and interaction of PHD3 with HIF-1α. Acetylation of HIF-1α has been proposed to result in increased interaction of HIF-1α with pVHL and induced pVHL-mediated ubiquitination, which leads to the proteasomal degradation of HIF-1α. HEXIM1 also attenuated the interaction of HIF-1α with HDAC1 (histone deacetylase 1), resulting in acetylation of HIF-1α. The consequence of HEXIM1 down-regulation of HIF-1α protein expression is attenuated expression of HIF-1α target genes in addition to VEGF and inhibition of HIF-1α-regulated cell invasion.
Total and Conceptual Vocabulary in Spanish–English Bilinguals From 22 to 30 Months: Implications for Assessment
Authors: Core Cynthia , Hoff Erika , Rumiche Rosario , Señor Melissa
Published: September 2013

Purpose

Vocabulary assessment holds promise as a way to identify young bilingual children at risk for language delay. This study compares 2 measures of vocabulary in a group of young Spanish–English bilingual children to a single-language measure used with monolingual children.

Method

Total vocabulary and conceptual vocabulary were used to measure mean vocabulary size and growth in 47 Spanish–English bilingually developing children from 22 to 30 months of age based on results from the MacArthur–Bates Communicative Development Inventory (CDI; Fenson et al., 1993) and the Inventario del Desarrollo de Habilidades Comunicativas (Jackson-Maldonado et al., 2003). Bilingual children's scores of total vocabulary and conceptual vocabulary were compared with CDI scores for a control group of 56 monolingual children.

Results

The total vocabulary measure resulted in mean vocabulary scores and average rate of growth similar to monolingual growth, whereas conceptual vocabulary scores were significantly smaller and grew at a slower rate than total vocabulary scores. Total vocabulary identified the same proportion of bilingual children below the 25th percentile on monolingual norms as the CDI did for monolingual children.

Conclusion

These results support the use of total vocabulary as a means of assessing early language development in young bilingual Spanish–English speaking children.
Perception of Speech Modulation Cues by 6-Month-Old Infants
Authors: Cabrera Laurianne , Bertoncini Josiane , Lorenzi Christian
Published: September 2013

Purpose

The capacity of 6-month-old infants to discriminate a voicing contrast (/aba/–/apa/) on the basis of
amplitude modulation (AM) cues
and
frequency modulation (FM) cues
was evaluated.

Method

Several vocoded speech conditions were designed to either degrade FM cues in 4 or 32 bands or degrade AM in 32 bands. Infants were familiarized to the vocoded stimuli for a period of either 1 or 2 min. Vocoded speech discrimination was assessed using the head-turn preference procedure.

Results

Infants discriminated /aba/ from /apa/ in each condition; however, familiarization time was found to influence strongly infants' responses (i.e., their preference for novel vs. familiar stimuli).

Conclusions

Six-month-old infants do not require FM cues and can use the slowest (< 16 Hz) AM cues to discriminate voicing. Moreover, 6-month-old infants can use AM cues extracted from only 4 broad-frequency bands to discriminate voicing.
Why Words Are Hard for Adults With Developmental Language Impairments
Authors: McGregor Karla K. , Licandro Ulla , Arenas Richard , Eden Nichole , Stiles Derek , Bean Allison , Walker Elizabeth
Published: September 2013

Purpose

To determine whether word learning problems associated with developmental language impairment (LI) reflect deficits in encoding or subsequent remembering of forms and meanings.

Method

Sixty-nine 18- to 25-year-olds with LI or without (the normal development [ND] group) took tests to measure learning of 16 word forms and meanings immediately after training (encoding) and 12 hr, 24 hr, and 1 week later (remembering). Half of the participants trained in the morning, and half trained in the evening.

Results

At immediate posttest, participants with LI performed more poorly on form and meaning than those with ND. Poor performance was more likely among those with more severe LI. The LI–ND gap for word form recall widened over 1 week. In contrast, the LI and ND groups demonstrated no difference in remembering word meanings over the week. In both groups, participants who trained in the evening, and therefore slept shortly after training, demonstrated greater gains in meaning recall than those who trained in the morning.

Conclusions

Some adults with LI have encoding deficits that limit the addition of word forms and meanings to the lexicon. Similarities and differences in patterns of remembering in the LI and ND groups motivate the hypothesis that consolidation of declarative memory is a strength for adults with LI.

Supplemental Material

https://doi.org/10.23641/asha.14963583
Effects of Lexical Tone Contour on Mandarin Sentence Intelligibility
Authors: Chen Fei , Wong Lena L. N. , Hu Yi
Published: September 2013

Purpose

This study examined the effects of lexical tone contour on the intelligibility of Mandarin sentences in quiet and in noise.

Method

A text-to-speech synthesis engine was used to synthesize Mandarin sentences with each word carrying the original lexical tone, flat tone, or a tone randomly selected from the 4 Mandarin lexical tones. The synthesized speech signals were presented to 11 normal-hearing listeners for recognition in quiet and in speech-shaped noise at 0 dB signal-to-noise ratio.

Results

Normal-hearing listeners nearly perfectly recognized the Mandarin sentences produced with modified tone contours in quiet; however, performance declined substantially in noise.

Conclusions

Consistent with previous findings to some extent, the present findings suggest that lexical tones are relatively redundant cues for Mandarin sentence intelligibility in quiet and that other cues could compensate for the distorted lexical tone contour. However, in noise, the results provide direct evidence that lexical tone contour is important for the recognition of Mandarin sentences.
Effects of Spaced Retrieval Training on Semantic Memory in Alzheimer's Disease: A Systematic Review
Authors: Oren Shiri , Willerton Charlene , Small Jeff
Published: September 2013

Purpose

This article reports on a systematic review and meta-analysis of the effects of spaced retrieval training (SRT) on semantic memory in people with Alzheimer's disease (AD) or related disorder.

Method

An initial systematic database search identified 454 potential studies. After screening and de-duplication, 35 studies that used SRT with the population of interest remained. The authors used an appraisal point system to evaluate the quality of the studies. Twelve of the 35 studies met inclusion and exclusion criteria and passed the appraisal point system cutoff. The 12 studies were classified as Level I and II evidence.

Results

Although the 12 studies varied in terms of design, methodology, and quality, SRT was shown to have important positive effects on learning semantic information across the included studies.

Conclusions

The findings indicate that SRT is an effective semantic memory training technique for people with AD, and consequently, recommendations are suggested for implementing SRT in practice settings. Continued research in this domain is also warranted to address limitations and gaps in the current body of research evidence, including variability in SRT protocols, effects of dementia severity on learning outcomes, maintenance effects, generalization, and the role of explicit and implicit learning in SRT.

Supplemental Material

https://doi.org/10.23641/asha.6170435
Sixteen-Year Change in Acoustic-Admittance Measures Among Older Adults: Data From a Population-Based Study
Authors: Nondahl David M. , Cruickshanks Karen J. , Wiley Terry L. , Tweed Ted S. , Dalton Dayna S.
Published: September 2013

Purpose

The primary purpose of this study was to measure the 16-year change in peak compensated static acoustic admittance (Peak Y
tm
) in a population-based cohort of older adults, and to determine whether age was associated with any observed change in Peak Y
tm
. Other tympanometric measures also were taken and analyzed.

Method

Data from two examinations (1993–1995 and 2009–2010) of the population-based Epidemiology of Hearing Loss Study (
n
= 1,439 with data at both examinations, ages 48–84 years at baseline) were utilized to assess 16-year change. Tympanometric measures were taken using a 226-Hz probe tone, a positive-to-negative direction of pressure change, and a measured pump speed of 600/200 daPa/s.

Results

During the 16-year period, Peak Y
tm
declined an average of 0.009 mmho/year (0.009/year for women, 0.007/year for men). Among women, older baseline age was associated with greater decline in Peak Y
tm
. Among men, baseline age was associated with change in Peak Y
tm
, but in a nonlinear pattern. Other tympanometric measures demonstrated little change after 16 years.

Conclusions

These results demonstrate a small degree of middle-ear stiffening after 16 years among these older adults, but not enough to affect function in a manner that would influence clinical decisions.
Comments on ‘Position‐tracking control of underactuated autonomous underwater vehicles in the presence of unknown ocean currents’
Authors: Xie Wen‐Jing , Ma Bao‐Li
Published: September 2013

The control law in the commented paper is indicated to be non‐causal, which cannot be applied in practical engineering directly and leads to the stability analysis incomplete. To correct the flaws, the control law is modified by solving the implicit equation in that study, and the incomplete stability analysis of the closed‐loop system is finished. Finally, simulation results illustrate the effectiveness of the modified control law.
Improved prescribed performance constraint control for a strict feedback non‐linear dynamic system
Authors: Han Seong Ik , Lee Jang Myung
Published: September 2013

An improved prescribed performance control using a backstepping technique and adaptive fuzzy is proposed for a strict feedback nonlinear dynamic system. A new virtual variable was defined to generate the virtual control that forces the tracking errors to fall within prescribed boundaries, and an adaptive fuzzy system was used to obtain required approximation performances. A strict feedback controller and adaptive laws for estimating the unknown non‐linear function were designed to avoid a singularity problem and calculation of the explosive number of terms generated by the error transformations of conventional error constraint method and the recursive steps of traditional backstepping control. Lyapunov stability analysis confirmed the boundedness and convergence of the closed‐loop system. The prescribed error constraint performance of the proposed control scheme was validated by applying it to control the position of a second‐order non‐linear system and a robot manipulator.
Complete synchronisation for two coupled logical systems
Authors: Li Fangfei , Lu Xiwen
Published: September 2013

This brief article studies the complete synchronisation of two logical systems coupled in the drive–response configuration, where the drive system is a Boolean network (BN), and the response system is a switched BN. Necessary and sufficient conditions are given when the transition matrix of the drive system is invertible, semi‐convergent or neither is. Finally, examples are worked out to illustrate the proposed results.
A hyperspectral imaging system for an accurate prediction of the above-ground biomass of individual rice plants
Authors: Feng Hui , Jiang Ni , Huang Chenglong , Fang Wei , Yang Wanneng , Chen Guoxing , Xiong Lizhong , Liu Qian
Published: September 2013

Biomass is an important component of the plant phenomics, and the existing methods for biomass estimation for individual plants are either destructive or lack accuracy. In this study, a hyperspectral imaging system was developed for the accurate prediction of the above-ground biomass of individual rice plants in the visible and near-infrared spectral region. First, the structure of the system and the influence of various parameters on the camera acquisition speed were established. Then the system was used to image 152 rice plants, which selected from the rice mini-core collection, in two stages, the tillering to elongation (T-E) stage and the booting to heading (B-H) stage. Several variables were extracted from the images. Following, linear stepwise regression analysis and 5-fold cross-validation were used to select effective variables for model construction and test the stability of the model, respectively. For the T-E stage, the R2 value was 0.940 for the fresh weight (FW) and 0.935 for the dry weight (DW). For the B-H stage, the R2 value was 0.891 for the FW and 0.783 for the DW. Moreover, estimations of the biomass using visible light images were also calculated. These comparisons showed that hyperspectral imaging performed better than the visible light imaging. Therefore, this study provides not only a stable hyperspectral imaging platform but also an accurate and nondestructive method for the prediction of biomass for individual rice plants.
Controlling viscous fingering in tapered Hele-Shaw cells
Authors: Al-Housseiny Talal T. , Stone Howard A.
Published: September 2013

We present a theoretical study of a variant of the classical viscous fingering instability, which occurs when a high viscosity fluid is displaced by a low viscosity fluid in a Hele-Shaw cell. In our system, the Hele-Shaw cell is tapered in the direction of fluid displacement. We consider two tapered Hele-Shaw geometries (rectilinear and radial), which have a constant depth gradient in the flow direction. We find that the presence of a depth gradient can alter the stability of the interface offering opportunities to control and tune fingering instabilities. In particular, the stability of the interface is now determined by both the viscosity contrast of the fluids and the ratio of the depth gradient to the capillary number of the system. We also demonstrate several applications of our analysis, including the inhibition of viscous fingering by controlling the injection flow rate in a radially tapered Hele-Shaw cell.
High contrast holograms using nanotube forest
Authors: Montelongo Yunuen , Chen Bingan , Butt Haider , Robertson John , Wilkinson Timothy D.
Published: September 2013

Nanotube forest behaves as highly absorbent material when they are randomly placed in sub-wavelength scales. Furthermore, it is possible to create diffractive structures when these bulks are patterned in a substrate. Here, we introduce an alternative to fabricate intensity holograms by patterning fringes of nanotube forest on a substrate. The result is an efficient intensity hologram that is not restricted to sub-wavelength patterning. Both the theoretical and experimental analysis was performed with good agreement. The produced holograms show a uniform behaviour throughout the visible spectra.
Lift evaluation of a two-dimensional pitching flat plate
Authors: Xia X. , Mohseni K.
Published: September 2013

Several previous experimental and theoretical studies have shown that a leading edge vortex (LEV) on an airfoil or wing can provide lift enhancement. In this paper, unsteady two-dimensional (2D) potential flow theory is employed to model the flow field of a pitching flat plate wing. A multi-vortices model is developed to model both the leading edge and trailing edge vortices (TEVs), which offers improved accuracy compared with using only single vortex at each separation location. The lift is obtained by integrating the unsteady Blasius equation. It is found that the motion of vortices contributes significantly to the overall aerodynamic force on the flat plate. A Kutta-like condition is used to determine the vortex intensity and location at the leading edge for large angle of attack cases; however, it is proposed to relax this condition for small angle of attack cases and apply a 2D shear layer model to calculate the circulation of the new added vortex. The results of the simulation are then compared with classical numerical, theoretical, and experimental data for canonical unsteady flat plat problems. Good agreement with these data is observed. Moreover, these results suggested that the leading edge vortex shedding for small angles of attack should be modeled differently than that for large angles of attack. Finally, the results of vortex motion vs. lift indicate that the slow convection of the LEV creates less negative lift while the rapid shedding of the TEV creates more positive lift. The difference between these two contributions of lift results in a total positive lift that lasts for about two chord-length travel of the plate. It is therefore concluded that the lift enhancement during the LEV “stabilization” above the wing is a combined effect of both the LEV and TEV motion. This also provides the insights for future active flow control of micro aerial vehicles (MAVs) that the formation and shedding process of LEVs and TEVs can be manipulated to provide lift enhancement.
Carrier mobility in rubrene-doped 4-cyano-4′-pentylbiphenyl studied by the time-of-flight method
Authors: Honma Michinori , Nose Toshiaki
Published: September 2013

We have investigated the transient photocurrent of rubrene-doped nematic liquid crystal using a time-of-flight examination. Drift mobilities on the order of 10−6 cm2/V s were obtained for both positive and negative carriers. The minimal dependence of the rubrene concentration on the drift mobility is indicative of the ionic conduction as carrier transport process. The product of the drift mobility and the viscosity obeys the Walden rule, further supporting the ionic carrier transport process.
Polaron dynamics in two-dimensional photon-echo spectroscopy of molecular rings
Authors: Huynh Thanh Duc , Sun Ke-Wei , Gelin Maxim , Zhao Yang
Published: September 2013

We have developed a new approach to the computation of third-order spectroscopic signals of molecular rings, by incorporating the Davydov soliton theory into the nonlinear response function formalism. The Davydov D1 and \documentclass[12pt]{minimal}\begin{document}$\tilde{\rm D}$\end{document}D̃ Ansätze have been employed to treat the interactions between the excitons and the primary phonons, allowing for a full description of arbitrary exciton-phonon coupling strengths. As an illustration, we have simulated a series of optical 2D spectra for two models of molecular rings.
Investigation of Fickian diffusion in the ternary mixture of 1,2,3,4-tetrahydronaphthalene, isobutylbenzene, and dodecane
Authors: Mialdun A. , Sechenyh V. , Legros J. C. , Ortiz de Zárate J. M. , Shevtsova V.
Published: September 2013

We present a comprehensive analysis of experimental results obtained for Fickian diffusion in the benchmark ternary liquid mixture of 1,2,3,4-tetrahydronaphthalene, isobutylbenzene, and dodecane (nC12) with equal mass fractions. Isothermal diffusion coefficients have been measured by two independent experimental methods: by Taylor dispersion technique, and by a counter flow cell fitted with an optical interferometry device. The experimental diffusion matrices have been critically analyzed regarding the Onsager reciprocal relations, for which we introduce a matrix asymmetry index s2 that is independent of the frame of reference and the component order.
Polyamorphism in cerium based bulk metallic glasses: Electronic and structural properties under pressure and temperature by x-ray absorption techniques
Authors: Belhadi L. , Decremps F. , Pascarelli S. , Cormier L. , Le Godec Y. , Gorsse S. , Baudelet F. , Marini C. , Garbarino G.
Published: September 2013

High pressure and high temperature x-ray absorption near edge spectroscopy experiments have been carried out on Ce60Al20Cu20 bulk metallic glass showing an electronic delocalization of the 4f-electron of cerium under pressure. In parallel, high pressure extended x-ray absorption fine structure spectroscopy reveals large structural modifications of the cerium local environment. This study provides experimental evidence that an electronic driven structural transformation occurs in cerium based bulk metallic glasses (Ce-BMGs). The effect of temperature on the hysteresis of this amorphous-amorphous phase transition is also discussed, suggesting the existence of a critical point in the phase diagram of Ce-BMGs. This work will encourage further investigations on Ce-based metallic glasses phase diagrams in order to support, or refute, the actual theoretical understanding of polyamorphism.
Superparamagnetic nanoparticle detection using second harmonic of magnetization response
Authors: Zhang Yi , Murata Hayaki , Hatsukade Yoshimi , Tanaka Saburo
Published: September 2013

We introduce a method to improve the detection sensitivity for the magnetization M of superparamagnetic nanoparticles (MNP). The M response of MNP to an applied magnetic field H (M–H characteristics) could be divided into a linear region and a saturation region, which are separated at a transition point Hk. When applying an excitation magnetic field (Hac) with a frequency ω0 and an additional dc bias field Hdc = Hk, the second harmonic of M reaches the maximum due to the nonlinearity of the M–H characteristics. It is stronger than any other harmonics and responsible for small Hac without a threshold. The second harmonic selected as the readout criterion for M response of MNP is systematically analyzed and experimentally proven.
Near-field single tractor-beam acoustical tweezers
Authors: Mitri F. G.
Published: September 2013

The possibility to trap a sphere in the near-field of a single-beam piston transducer is theoretically demonstrated. Conditions are found where a rigid, fluid, elastic, and viscoelastic sphere with arbitrary radius placed in the near-field and centered on the axis of a circular piezoelectric transducer vibrating uniformly, experiences a pulling force, so the acoustical waves act as a “tractor” beam. Numerical predictions illustrate the theory with particular emphasis on the distance from the source, the size of the transducer, and the elastic properties of the sphere. Those results can potentially suggest a simple and reliable method in designing acoustical tweezers.
High permittivity cerium oxide thin films on AlGaN/GaN heterostructures
Authors: Fiorenza P. , Greco G. , Fisichella G. , Roccaforte F. , Malandrino G. , Lo Nigro R.
Published: September 2013

Cerium oxide (CeO2) thin films have been grown by metal-organic chemical vapor deposition on AlGaN/GaN heterostructures and their insulating properties as gate dielectric layer have been explored. The deposited thin films have been found to be textured on the GaN based heterostructures and exhibited a permittivity of 26. This high permittivity value and large band gap are certainly advantageous with respect to other reported materials for the metal insulator semiconductor high electron mobility transistor application. The reduced leakage current density clearly suggests that these CeO2 films are very promising as gate dielectric for AlGaN/GaN transistors low power consumption technology.
Reversible pressure-induced switching of droplet mobility after impingement on porous surface media
Authors: Vourdas N. , Tserepi A. , Stathopoulos V. N.
Published: September 2013

We present a generic method to reversibly switch the mobility of a droplet after impingement onto a hydrophobic porous surface, from a sticky to a slippery state and back. By means of a pneumatic system, the backpressure of the porous medium is adjusted to favor the pressure balance towards the desired state. By applying overpressure above a certain threshold, the antiwetting pressures increase over the wetting pressures, which eventually results to a slippery state, while vacuum enhances the wetting pressures, thus, rendering the droplet sticky. This pressure-induced switching method is very flexible and can be applied even after decay of the hydrophobic character of the porous medium, does not entail the use of a superhydrophobic or hierarchical surface, and can be applied for actuation and valving in microfluidics.
Photoexcited carrier recombination in wide m-plane InGaN/GaN quantum wells
Authors: Marcinkevičius S. , Kelchner K. M. , Kuritzky L. Y. , Nakamura S. , DenBaars S. P. , Speck J. S.
Published: September 2013

Carrier recombination in single 10 nm wide m-plane homoepitaxial In0.15Ga0.85N/GaN quantum wells was examined by time-resolved photoluminescence. The radiative recombination time at 3.5 K was found to be short, about 0.5 ns. This value and the single-exponential luminescence decay show that the localized exciton recombination is not affected by the in-plane electric field. At room temperature, the nonradiative recombination was prevalent. The data indicate that the nonradiative recombination proceeds via efficient recombination centers. Complexes of Ga vacancies with oxygen and/or related interface defects are suggested to play this role and thus provide a direction for future improvements in materials' quality.
Elementary array of Fabry-Pérot waveguide resonators with tunable coupling
Authors: Lepert Guillaume , Hinds E. A. , Rogers Helen L. , Gates James C. , Smith Peter G. R.
Published: September 2013

We recently proposed that an array of optical cavities containing quantum emitters could be interconnected by an optical bus made of Fabry Pérot resonators lying side by side, for applications in quantum information processing and quantum simulation. Here, we demonstrate the feasibility of this geometry. We show that the resonators can be conveniently coupled, and that the coupling rate between adjacent waveguides can be widely tuned using the thermo-optic effect. The device is linearly scalable and can be combined with other integrated devices, making it more generally applicable as an adjustable optical delay line or optical interconnect.
Magnon-mediated thermal rectification with forward-bias and breakdown temperatures
Authors: Martínez-Flores J. J. , Licea-Jimenez L. , Perez Garcia S. A. , Alvarez-Quintana J.
Published: September 2013

In an ideal model, a thermal rectifier is the thermal equivalent of the electrical diode. A device which leads a greater heat flow in one direction than another one. Currently used bulk and molecular mechanisms which can potentially result in thermal rectifying behavior have not evidenced that the rectification factor can reach one order of magnitude, which is an arbitrary limit required to deem the effect useful for engineered systems. Here, we have succeeded in building thermal diodes with thermal rectification factors up to 1.62 under 29 K temperature bias. Devices manipulate heat via the activation and deactivation of magnons in magnetic materials at room temperature through the Curie temperature. Furthermore, this factor can be enhanced further by improving the magnetic properties in the material and by increasing the thermal bias. In addition, thermal diodes present a well-defined breakdown as well as forward temperatures which control accurately the on state of the device. This approach paves the way to pursuit the one order limit at room temperature in a simple way and opens a new route towards the next generation of thermal devices.
Electron nongyrotropy in the context of collisionless magnetic reconnection
Authors: Aunai Nicolas , Hesse Michael , Kuznetsova Maria
Published: September 2013

Collisionless magnetized plasmas have the tendency to isotropize their velocity distribution function around the local magnetic field direction, i.e., to be gyrotropic, unless some spatial and/or temporal fluctuations develop at the particle gyroscales. Electron gyroscale inhomogeneities are well known to develop during the magnetic reconnection process. Nongyrotropic electron velocity distribution functions have been observed to play a key role in the dissipative process breaking the field line connectivity. In this paper, we present a new method to quantify the deviation of a particle population from gyrotropy. The method accounts for the full 3D shape of the distribution and its analytical formulation allows fast numerical computation. Regions associated with a significant degree of nongyrotropy are shown, as well as the kinetic origin of the nongyrotropy and the fluid signature it is associated with. Using the result of 2.5D Particle-In-Cell simulations of magnetic reconnection in symmetric and asymmetric configurations, it is found that neither the reconnection site nor the topological boundaries are generally associated with a maximized degree of nongyrotropy. Nongyrotropic regions do not correspond to a specific fluid behavior as equivalent nongyrotropy is found to extend over the electron dissipation region as well as in non-dissipative diamagnetic drift layers. The localization of highly nongyrotropic regions in numerical models and their correlation with other observable quantities can, however, improve the characterization of spatial structures explored by spacecraft missions.
Design of a surface-scanning coil detector for direct bacteria detection on food surfaces using a magnetoelastic biosensor
Authors: Chai Yating , Wikle Howard C. , Wang Zhenyu , Horikawa Shin , Best Steve , Cheng Zhongyang , Dyer Dave F. , Chin Bryan A.
Published: September 2013

The real-time, in-situ bacteria detection on food surfaces was achieved by using a magnetoelastic biosensor combined with a surface-scanning coil detector. This paper focuses on the coil design for signal optimization. The coil was used to excite the sensor's vibration and detect its resonant frequency signal. The vibrating sensor creates a magnetic flux change around the coil, which then produces a mutual inductance. In order to enhance the signal amplitude, a theory of the sensor's mutual inductance with the measurement coil is proposed. Both theoretical calculations and experimental data showed that the working length of the coil has a significant effect on the signal amplitude. For a 1 mm-long sensor, a coil with a working length of 1.3 mm showed the best signal amplitude. The real-time detection of Salmonella bacteria on a fresh food surface was demonstrated using this new technology.
A framework for estimating potential fluid flow from digital imagery
Authors: Luttman Aaron , Bollt Erik M. , Basnayake Ranil , Kramer Sean , Tufillaro Nicholas B.
Published: September 2013

Given image data of a fluid flow, the flow field, ⟨u,v⟩, governing the evolution of the system can be estimated using a variational approach to optical flow. Assuming that the flow field governing the advection is the symplectic gradient of a stream function or the gradient of a potential function—both falling under the category of a potential flow—it is natural to re-frame the optical flow problem to reconstruct the stream or potential function directly rather than the components of the flow individually. There are several advantages to this framework. Minimizing a functional based on the stream or potential function rather than based on the components of the flow will ensure that the computed flow is a potential flow. Next, this approach allows a more natural method for imposing scientific priors on the computed flow, via regularization of the optical flow functional. Also, this paradigm shift gives a framework—rather than an algorithm—and can be applied to nearly any existing variational optical flow technique. In this work, we develop the mathematical formulation of the potential optical flow framework and demonstrate the technique on synthetic flows that represent important dynamics for mass transport in fluid flows, as well as a flow generated by a satellite data-verified ocean model of temperature transport.
Theoretical studies on distribution of resistances in multilevel bipolar oxide resistive memory by Monte Carlo method
Authors: Hur Ji-Hyun , Ryul Lee Seung , Lee Myoung-Jae , Cho Seong-Ho , Park Youngsoo
Published: September 2013

We simulate resistance distributions of multilevel oxide bipolar resistive random access memories (ReRAMs) through a physical model with Monte Carlo method. The model is used to explain frequently noticed proportionality relationship between distributions of resistances and multi-levels program voltages. By comparing with the experimental results obtained with TaOx/Ta2O5 bipolar ReRAM, the model is verified to have a good consistency with experiments not only qualitatively but also quantitatively. We demonstrate that the resistance distributions responses are basically determined by the ion migration barrier in the resistance varying thin oxide layer which means that it is a nearly intrinsic material property.
Tuning the giant inverse magnetocaloric effect in Mn2−xCrxSb compounds
Authors: Caron L. , Miao X. F. , Klaasse J. C. P , Gama S. , Brück E.
Published: September 2013

Structural, magnetic, and magnetocaloric properties of Mn2-xCrxSb compounds have been studied. In these compounds, a first order magnetic phase transition from the ferrimagnetic to the antiferromagnetic state occurs with decreasing temperature, giving rise to giant inverse magnetocaloric effects that can be tuned over a wide temperature interval through changes in substitution concentration. Entropy changes as high as 7.5 J/kg K have been observed, and a composition independent entropy change is obtained for several different concentrations/working temperatures, making these compounds suitable candidates for a composite working material.
Tunable atomic force microscopy bias lithography on electron beam induced carbonaceous platforms
Authors: Kurra Narendra
Published: September 2013

Tunable local electrochemical and physical modifications on the carbonaceous platforms are achieved using Atomic force microscope (AFM) bias lithography. These carbonaceous platforms are produced on Si substrate by the technique called electron beam induced carbonaceous deposition (EBICD). EBICD is composed of functionalized carbon species, confirmed through X-ray photoelectron spectroscopy (XPS) analysis. AFM bias lithography in tapping mode with a positive tip bias resulted in the nucleation of attoliter water on the EBICD surface under moderate humidity conditions (45%). While the lithography in the contact mode with a negative tip bias caused the electrochemical modifications such as anodic oxidation and etching of the EBICD under moderate (45%) and higher (60%) humidity conditions respectively. Finally, reversible charge patterns are created on these EBICD surfaces under low (30%) humidity conditions and investigated by means of electrostatic force microscopy (EFM).
Reliable strain measurement in transistor arrays by robust scanning transmission electron microscopy
Authors: Kim Suhyun , Kim Joong Jung , Jung Younheum , Lee Kyungwoo , Byun Gwangsun , Hwang KyoungHwan , Lee Sunyoung , Lee Kyupil
Published: September 2013

Accurate measurement of the strain field in the channels of transistor arrays is critical for strain engineering in modern electronic devices. We applied atomic-resolution high-angle annular dark-field scanning transmission electron microscopy to quantitative measurement of the strain field in transistor arrays. The quantitative strain profile over 20 transistors was obtained with high reliability and a precision of 0.1%. The strain field was found to form homogeneously in the channels of the transistor arrays. Furthermore, strain relaxation due to the thin foil effect was quantitatively investigated for thicknesses of 35 to 275 nm.
Manufacturing and wetting low-cost microfluidic cell separation devices
Authors: Pawell Ryan S. , Inglis David W. , Barber Tracie J. , Taylor Robert A.
Published: September 2013

Deterministic lateral displacement (DLD) is a microfluidic size-based particle separation or filter technology with applications in cell separation and enrichment. Currently, there are no cost-effective manufacturing methods for this promising microfluidic technology. In this fabrication paper, however, we develop a simple, yet robust protocol for thermoplastic DLD devices using regulatory-approved materials and biocompatible methods. The final standalone device allowed for volumetric flow rates of 660 μl min−1 while reducing the manufacturing time to <1 h. Optical profilometry and image analysis were employed to assess manufacturing accuracy and precision; the average replicated post height was 0.48% less than the average post height on the master mold and the average replicated array pitch was 1.1% less than the original design with replicated posts heights of 62.1 ± 5.1 μm (mean ± 6 standard deviations) and replicated array pitches of 35.6 ± 0.31 μm.