Miracle-dz/UniFAR-FTUs huggingface dataset:
Auditory spatial resolution in the barn owl under echoic and anechoic conditions

Experiments were designed to allow direct comparison of auditory spatial resolution, measured behaviorally, with that of single space‐specific neurons in the barn owl’s midbrain. Behavioral measurements of spatial discrimination were obtained using habituation and recovery of the pupillary dilation response (PDR). The acoustically evoked PDR habituates to repeated presentation of a sound, and recovers if the location changes. Thus, the difference in magnitudes of PDRs evoked by a sequence of test and habituating stimuli can be quantified using signal detection theory to provide a measure of discrimination [‘‘p(c),’’ computed from empirical ROC curves]. The minimum audible angles (MAAs) for single sound sources separated in azimuth and elevation were 3° and 9°, respectively. Under simulated echoic conditions, MAAs increased by a factor of 2 for direct sources, and 4 for simulated reflections. Neuronal discrimination was similarly quantified using ROC curves to calculate p(c) for spike discharges evoked by .
On Estimates of Reachable Sets of Multidimensional Control Systems

Abstract The paper is devoted to the problem of construction of external estimates for the reachable set of a multidimensional control system by means of vector estimators. A considered system permits a decomposition into several independent subsystems (like for linear subsystems), which are connected to each other by means of nonlinear interconnections. For each of the subsystems, an external estimate of the reachable set is assumed to be known. An estimate for the reachable set of the combined system is given on the base of estimates for subsystems and use of analogs of vector Lyapunov functions. Copyright ©2011 IF AC
Ising Models of Social Impact: the Role of Cumulative Advantage

A statistical mechanical model for Latane's theory of social impact is discussed and extended to include learning. When the persuasive and supportive strengths are not equal, a ferromagnetic and a spin-glass phase emerge. When the persuasive and supportive strengths are equal, and a cumulative advantage learning scheme is used, then the model exhibits two ferromagnetic phases distinguishable by the structure of the correlations. In the first phase the correlations are normally distributed. In the second phase all elements are shown to be highly correlated with either a single element or a small number of elements. These leaders determine the equilibrium state of the system.
Acoustic streaming past a vibrating wall

The classic phenomenon of acoustic streaming is reconsidered for the case in which the boundary layers on the vibrating and the still walls are of comparable importance, in the small-gap configuration suitable for an ultrasonic motor. The effect of temperature oscillations is included in the analysis, as well as is the impedance matching with the elastic oscillations in the vibrating wall.
Effect of percolation on thermal transport in nanotube composites

The effective thermal conductivity of two-dimensional (2D) nanocomposites composed of carbon nanotubes (CNTs) dispersed in a host substrate is simulated to quantify the role of tube percolation on the thermal transport. The model is in excellent agreement with a 2D effective medium theory for low tube densities, but departs significantly from it when tube-tube interaction becomes significant. It is found that percolation effects may play a role for tube-tube and tube-substrate thermal resistance parameters typical of CNT composites. They are quantified in terms of a conductivity exponent for a range of governing parameters.
Enhancement of Light Extraction from Organic Light-Emitting Diodes with Two-Dimensional Hexagonally Nanoimprinted Periodic Structures Using Sequential Surface Relief Grating

Electric characteristics of organic light-emitting diodes (OLEDs) with two-dimensional hexagonally nanoimprinted periodic structures were investigated, and enhanced light extraction from this device was confirmed. A master mold was fabricated from an azobenzene polymer thin film patterned by sequential surface relief grating formation into a three-directional structure. The device shows a higher current density and a higher current efficiency, although leakage current is also higher than that of a device without periodic structures. These results are caused by the extraction of diffracted light from waveguided and substrate-guided light even when incident light has larger angles than the critical angle for total reflection.
STABILITY AND BOUNDARY CONTROLLABILITY OF A LINEARIZED MODEL OF FLOW IN AN ELASTIC TUBE

We consider a model describing the flow of a fluid inside an elastic tube that is connected to two tanks. We study the linearized system through semigroup theory. Controlling the pressures in the tanks renders a hyperbolic PDE with boundary control. The linearization induces a one-dimensional linear manifold of equilibria; when those are factored out, the corresponding semigroup is exponentially stable. The location of the eigenvalues in dependence on the viscosity is discussed. Exact boundary controllability of the system is achieved by the Riesz basis approach including generalized eigenvectors. A minimal time for controllability is given. The corresponding result for internal distributed control is stated.
Stationary and dynamic consensus of second-order multi-agent systems with Markov jumping input delays

This study investigates the consensus problem of second-order multi-agent systems which are subject to Markov jumping input delays. A unified framework is established to address both the stationary and dynamic consensus issues in sampled-data settings. The authors first derive the sufficient conditions for consensus in terms of matrix inequalities. Thereafter, a cone complementarity linearisation-based algorithm and its simplified implementation alternative are proposed for the delay-dependent switching controller design. Compared with the existing works, the proposed algorithms possess less conservativeness and larger solution domains. Finally, numerical examples are provided to illustrate the effectiveness of the proposed approaches.
Wigner functions for paraxial and nonparaxial fields

The Wigner function gives an intuitive representation of coherent and partially coherent wave fields in the frequency domain, which takes the form a ray weight distribution. However, this weight distribution is conserved along rays only for paraxial or significantly incoherent fields. Generalizations of the Wigner function have been defined for propagation through transparent homogeneous media that are exactly conserved along rays for any angular spread and state of coherence. A series expression is derived here for calculating these nonparaxial generalizations starting from the standard Wigner function.
Collision-free trajectory planning for manipulatiors using generalized pattern search

A Generalized Pattern Search algorithm (GPS) is introduced to design a collision-free trajectory for planar redundant manipulators. Cubic-spline interpolation trajectory for the end-effector is designed a priori by selecting three intermediate points around the workspace obstacles. The GPS algorithm ensures that none of the selected points lies inside any of the obstacles. The end-effector will follow the prescribed trajectory in excellent manner without colliding with the obstacles. Simulation studies are carried out for three different obstacles to prove the validity of the proposed algorithm.
Complete analyis of a new method for obtaining the characteristics of slab optical waveguides with step index profiles from measurements of effective indices

A new method for characterizing step index optical waveguides from experimental values of effective indices of guided modes is presented. We find the refractive index of the film by means of a linear fitting between the square of effective index and the square of the sum of mode index plus one, avoiding the use of the highest mode; further, statistical procedure has been used to evaluate the waveguide depth through the dispersion equation (without solving the transcendental equation) avoiding the use of zeroth mode. We have checked the method by using the Monte Carlo method, analyzing all possible guides with step index profile by means of normalized parameters. Furthermore, we compare the method with those presented by other authors and we find good agreement. The proposed method is easier than others and the error analysis shows its accuracy to be good.
Brackett-alpha line profiles of young stellar objects

Profiles of the Br-alpha line of H I at a velocity resolution of 45 km/s are presented for the compact imbedded infrared objects BN, S106/IRS 3, GLS 490, GL 961, GL 989, Mon. R2/IRS 2, and for the visible objects LkH-alpha 101, T Tau, and R Mon. A proportionality obtained between Br-alpha luminosity and bolometric luminosity is shown to extend over three orders of magnitude, supporting the idea that the physical conditions and gas motions in the circumstellar envelopes of stellar objects are closely related over a wide range of luminosities. The Br-alpha line strengths are compared to radio continuum flux densities in the context of stellar wind models. Momentum deposition rates deduced from Br-alpha or radio continuum fluxes are consistent with those available in the radiation fields, which appear capable of driving the ionized gas outflows in the vicinity of the core sources. The results of a comparison of the H-alpha and Br-alpha profiles for T Tau are discussed.
Energetic negative ion and neutral atom beam generation at passage of laser accelerated high energy positive ions through a liquid spray

Beams of energetic negative ions and neutral atoms are obtained from water and ethanol spray targets irradiated by high intensity (5×1019 W/cm2) and ultrashort (50 fs) laser pulses. The resulting spectra were measured with the Thomson parabola spectrometer, which enabled absolute measurements of both: positive and negative ions. The generation of a beam of energetic neutral hydrogen atoms was confirmed with CR-39 track detectors and their spectral characteristics have been measured using time of flight technique. Generation is ascribed to electron-capture and -loss processes in the collisions of laser-accelerated high-energy protons with spray of droplets. The same method can be applied to generate energetic negative ions and neutral atoms of different species.
The effect of surface roughness on the determination of optical constants of CuInSe2 and CuGaSe2 thin films

To investigate the effect of surface roughness on the calculation of optical constants, e.g., the complex refractive index n+ik or (n,k) of CuIn1−xGaxSe2 (CIGSe) thin films, we took CuInSe2 (CISe) and CuGaSe2 (CGSe) as examples and applied the “Modified Transfer-Matrix (MTM)” method to calculate optical constants with considering the effect of scattering due to surface roughness. Compared to the Transfer-Matrix (TM) method without considering surface roughness, it was revealed that the MTM method could improve the accuracy of calculation. The calculated refractive index values from the MTM method increase by 6.89% for CISe and 2.59% for CGSe in contrast to those from the TM method. In addition, bromine solution was confirmed via Scanning Electron Microscopy and Atomic Force Microscopy to be able to reduce the surface roughness. Calculated results from smoothened samples showed that the accuracy of calculated optical constants was further improved. Finally, optical constants calculated by the MTM method we.
A block-based watermarking scheme for image tamper detection and self-recovery

In this paper, we present an effective block-based digital fragile watermarking scheme for image tamper detection and recovery. The proposed scheme embeds watermarks consisting of the authentication data and the recovery data into image blocks. It adopts parity check and the intensity-relation check to thwart various malicious attacks. In the tamper detection process, instead of independently testing the embedded authentication data of each block, we take the block-neighbourhood into account and utilize a hierarchical structure to determine the legitimacy of image blocks. Experimental results show that the proposed scheme can effectively resist collage attack, vector quantization (VQ) attack and constant-average attack, while sustaining superior accuracy of tamper localization. Furthermore, the results reveal that the tampered images can be successfully self-recovered with acceptable visual quality.
Silenced PITX1 promotes chemotherapeutic resistance to 5-fluorocytosine and cisplatin in gastric cancer cells

Resistance to chemotherapeutic drugs leads to a poor prognosis in gastric cancer (GC). The present study aimed to assess the association between pituitary homeobox paired homeodomain transcription 1 (PITX1) expression and the sensitivity of GC cells to the chemotherapeutic drugs 5-fluorouracil (5-FU) and cisplatin (CDDP). In the present study, the gastric cancer cell lines GES-1, AGS, BGC-823, MCG-803 and SGC-7901 were used. The expression of PITX1 was determined via reverse transcription-quantitative polymerase chain reaction in GC cell lines. AGS and BGC-823 cells, which exhibit a decreased PITX1 expression, were transfected with a PITX1 cDNA construct and its control vector. MCG-803 and SGC-7901 cells, which exhibit an increased PITX1 expression, were transfected with siRNA against PITX1 and its control scramble sequence. A Cell Counting kit-8 assay was performed to determine the impact of PITX1 expression on the sensitivity of GC cells to 5-FU and CDDP. The Cancer Genome Atlas database was used to analyze the expression of PITX1 with GC prognosis in the Asian population and to assess the potential mechanism of PITX1 in 5-FU and CDDP resistance. The results revealed that the overexpression of PIXT1 increased the sensitivity of GC cells to 5-FU/CDDP. The combination of 5-FU/CDDP and PITX1 overexpression also reduced the proliferation of GC cells. Additionally, PIXT1 knockdown decreased the sensitivity of GC cells to 5-FU/CDDP. TCGA data revealed that a lower expression of PITX1 is exhibited in Asian GC patients than in normal individuals. GC patients with a lower expression of PITX1 had a poor prognosis. The expression of PITX1 affected the sensitivity of GC cells to 5-FU/CDDP, indicating that PITX1 may increase the efficacy of treatment in GC patients.
Diagnostic features in two-dimensional light scattering patterns of normal and dysplastic cervical cell nuclei

Dysplastic progression in epithelial tissues is linked to changes in morphology and internal structure of cell nuclei. These changes lead to alterations in nuclear light scattering profiles that can potentially be monitored for diagnostic purposes. Numerical tools allow for simulation of complex nuclear models and are particularly useful for quantifying the optical response of cell nuclei as dysplasia progresses. In this study, we first analyze a set of quantitative histopathology images from twenty cervical biopsy sections stained with Feulgen-thionin. Since Feulgen-thionin is stoichiometric for DNA, the images enable us to obtain detailed information on size, shape, and chromatin content of all the segmented nuclei. We use this extensive data set to construct realistic three-dimensional computational models of cervical cell nuclei that are representative of four diagnostic categories, namely normal or negative for dysplasia, mild dysplasia, moderate dysplasia, and severe dysplasia or carcinoma in situ (CIS). We then carry out finite-difference time-domain simulations to compute the light scattering response of the constructed models as a function of the polar scattering angle and the azimuthal scattering angle. The results show that these two-dimensional scattering patterns exhibit characteristic intensity ridges that change form with progression of dysplasia; pattern processing reveals that Haralick features can be used to distinguish moderately and severely dysplastic or CIS nuclei from normal and mildly dysplastic nuclei. Our numerical study also suggests that different angular ranges need to be considered separately to fully exploit the diagnostic potential of two-dimensional light scattering measurements.
Effective desynchronization with a stimulation technique based on soft phase resetting

A composite stimulation technique is presented here which effectively desynchronizes a cluster of globally coupled phase oscillators in the presence of noise by means of a soft (i.e. slow and mild) reset. A composite stimulus consists of two different stimuli. The first stimulus is a short periodic pulse train, where the entraining frequency is close to the natural frequency of the cluster. In the course of several periods of the collective oscillation, the first stimulus entrains and, hence, resets (restarts) the cluster, independently of its initial dynamic state. With a fixed delay after the first stimulus the second stimulus, a single pulse, is delivered which desynchronizes the cluster by hitting it in a vulnerable state. The desynchronized cluster starts to resynchronize, since the incoherent state is unstable. Resynchronization can, nevertheless, be blocked by repeated administration of the same composite stimulus. Previously designed stimulation techniques use a hard (i.e. abrupt) reset. By contrast, a soft reset makes it possible to effectively desynchronize even if strong, quickly resetting stimuli are not available or not tolerated. Accordingly, this method is particularly mild and can be applied to effectively maintain incoherency in a population of oscillatory neurons which tend to synchronize their firing. The composite stimulation technique can be used i) for an improved, milder and demand-controlled deep brain stimulation for patients with Parkinson's disease or essential tremor and ii) for the manipulation of cerebral information processing by selectively blocking gamma activity.
Quantum transport properties of a two-channel atomic-sized magnetic contact

We propose a simple model to theoretically study the conductance of atomic-sized magnetic contacts. Our approach considers in detail the case of two-atom contacts with two spin channels, and the conductance is calculated using Landauer theory in the ballistic regime. For ferromagnetic contacts, we examine the large magnetoresistance effect obtained, when changing the magnetic configuration of the leads from parallel to antiparallel. We also discuss nonmagnetic transition metals nanocontacts, where conductance measurements display a behavior similar to magnetic contacts. Our treatment of the above phenomena reveals the important role played by quantum fluctuations in the contact region.
Simultaneous generation of tunable giant dispersive waves in the visible and mid-infrared regions based on photonic crystal fibers

Cherenkov radiation (CR) in both the visible and mid-infrared regions is simultaneously generated experimentally based on a photonic crystal fiber with two zero-dispersion wavelengths. The generation of CR in the visible region originates from solitons located in the anomalous group velocity dispersion (GVD) regime which are perturbed by positive third order dispersion. Conversely, the generation of CR in the mid-infrared region requires that the solitons in the anomalous GVD regime are perturbed by negative third order dispersion. The peak wavelength of the CR in the visible region can be tuned from 498 to 425 nm by increasing the average input pump power from 70 to 400 mW, while the peak wavelength of the CR in the mid-infrared region can be tuned from 1986 to 2279 nm by increasing the average input pump power from 70 to 320 mW.
FIONA in the trap: the advantages of combining optical tweezers and fluorescence

Technologies for the manipulation of single molecules have reached the resolution for the measurement of nanometre and sub-nanometre displacements and piconewton forces. In parallel with manipulation techniques, an array of single-molecule fluorescence detection methods have been developed to measure with great precision the position and/or the orientation of single biomolecules, as well as their conformational fluctuations. A new generation of instruments devoted to single-molecule biophysics is now emerging from the combination of two or more single-molecule techniques into one set-up. Particularly fruitful is the combination of manipulation techniques with single-molecule fluorescence techniques, allowing the detection of biomolecule position, conformation or biochemical state simultaneously with the measurement (or the external control) of mechanical output. Here we present the combination of optical tweezers and fluorescence imaging with nanometre accuracy (FIONA). The apparatus was tested on an actin filament labelled with a quantum dot and suspended in solution in a dumbbell configuration using the laser tweezers. This apparatus allows control of the mechanical conditions of a track (actin, microtubules, nucleic acids) while monitoring, by fluorescence, locomotion (and, possibly, biochemical state) of a motor on the track, thus being applicable to a large variety of biological systems.
The boundary layer on a spherical gas bubble

The equations governing the boundary layer on a spherical gas bubble rising steadily through liquid of small viscosity are derived. These equations are linear are linear and are solved in closed form. The boundary layer separates at the rear stagnation point of the bubble to form a thin wake, whose structure is determined. Thus the drag force can be calculated from the momentum defect. The value obtained is 12πaaUμ, where a is the bubble radius and U the terminal velocity, and this agrees with the result of Levich (1949) who argued from the viscous dissipation in the potential flow round the bubble. The next term in an expansion of the drag in descending fractional powers of R is found and the results compared with experiment.
An efficient numerically robust homotopy algorithm for H2 model reduction using the optimal projecton equations

Homotopy approaches have previously been developed for synthesizing #2 optimal reduced-order models. Some of the previous homotopy algorithms were based on directly solving the optimal projection equations, a set of two Lyapunov equations mutually coupled by a nonlinear term involving a projection matrix r, that characterize the optimal reduced-order model. These algorithms are numerically robust but suffer from the curse of large dimensionality. Subsequently, gradient-based homotopy algorithms were developed. To make these algorithms efficient and to eliminate singularities along the homotopy path, the basis of the reduced-order model was constrained to a minimal parameterization. However, the resultant homotopy algorithms sometimes experienced numerical ill-conditioning or failure due to the minimal parameterization constraint. This paper presents a new homotopy approach to solve the optimal projection equations for #2 model reduction. The current algorithm avoids the large dimensionality of the previou.