Miracle-dz/UniFAR-FTUs huggingface dataset:
Tunneling of femtosecond pulses through nanophotonic barriers: superluminal precursors

Amplitude–phase spectra of IR waves tunneling through a gradient dielectric nanophotonic barrier, found in the framework of an exactly solvable model of this medium, are used for optimization of superluminal reshaping of tunneling pulses. This barrier, characterized by a cut-off frequency Ω, determined by the shape of distribution of refractive index across the barrier, provides the tunneling regime for waves whose frequencies are less than Ω. In a spectral range, located nearby this cut-off frequency Ω, an almost reflectionless tunneling of these waves occurs, accompanied by large strongly dispersive phase shifts. These shifts outstrip in some spectral range the phase shifts accumulated by the same harmonics along the same way in free space. Depending on the detuning between the pulse carrier frequency ω0 and Ω, the interplay between superluminal (tunneling) and subluminal (transparent) harmonics results in an ultrafast reshaping of the transmitted waveform, yielding a pulse spatial broadening, formation of superluminal precursors at the front edge of the transmitted pulse, and the splitting of the pulse’s maximum, while the displacement of the center of gravity of reshaped pulse stays subluminal.
Threonine-to-lysine ratio in laying hens: physiological parameters and organ weight

The objective of this study was to evaluate the effect of threonine:digestible lysine ratio in the diet on the physiological variables and weight of organs of light laying hens. Two hundred and ten 47 week-old Dekalb White laying hens were distributed in a completely randomized design, with five levels of threonine (0.507; 0.552; 0.597; 0.642 and 0.677%) and seven replicates of six birds each. The experimental period was 10 weeks, totaling 62 days and more eight days for the animals to adapt. The physiological parameters of cloacal temperature (CT), respiratory rate (RR) and average surface temperature (AST) were recorded weekly (7:00 am, 10:00 am, 1:00 pm, 4:00 pm, and 7:00 pm); after solid and water fasting, the birds were slaughtered to assess the absolute weight of the organs. The time of day influenced (p < 0.05) the physiological parameters RR and AST, and CT showed a significant effect (p < 0.05) of increasing levels of digestible threonine. The total weight of the pancreas, proventriculus and lung showed a significant effect (p < 0.05) of the increase in the levels of digestible threonine. The respiratory rate is affected by the levels of threonine in the diet. The 0.687% level promoted hypertrophy of the pancreas, proventriculus and lung, promoting more significant activity of these organs.
A Canonical Correlation Approach for Selecting the Number of Dynamic Factors

In this article, we propose a selection procedure that allows us to consistently estimate the number of dynamic factors in a dynamic factor model. The procedure is based on a canonical correlation analysis of the static factors which has the advantage of being invariant to a rescaling of the factors. Monte Carlo simulations suggest that the proposed selection rule outperforms existing ones, in particular, if the contribution of the common factors to the overall variance is moderate or low. The new selection procedure is applied to the US macroeconomic data panel used in Stock and Watson [NBER working paper 11467 (2005)].
Progress of high-resolution photon scanning tunneling microscopy due to a nanometric fiber probe

The present status of a photon scanning tunneling microscope (PSTM) and its application are reviewed. In order to realize a nanometric apertured fiber probe, a highly reproducible chemical etching process was developed to realize a sharpened fiber with the cone angle and tip diameter as small as 14/spl deg/ and 3 nm, respectively. The possibility of tailoring the shapes of the sharpened fibers was presented. Chemical etching and nanometric photolithography were developed to fabricate a metallic aperture with a diameter of 30 nm (or even smaller) on the sharpened fiber tip. Imaging experiments with biological specimens were carried out by operating the PSTM in the collection mode and illumination mode geometries. Dependencies of these images on the polarization state of the incident light were found, and a resolution of 10 nm or even smaller was achieved. Nondestructive inspection of dielectric optical waveguides with subwavelength resolution was proposed by presenting the diagnosed results of a proton-exchanged LiTaO/sub 3/ waveguide. Possibilities of diagnosing nanometric active photonic devices were also demonstrated through imaging experiments of semiconductor quantum dots. Experiments on fluorescence detection from dye-doped nanometric polystyrene spheres confirmed the enhanced efficiency of coupling of the fluorescence to the fiber tip, and this was attributed to the spatially inhomogeneous spontaneous emission due to the short-range electromagnetic interaction between the sphere and probe tip. To demonstrate the possibilities of nanometric fabrication, high density optical storage, especially the photon-mode storage, was demonstrated to realize a stored circular pit of 100 nm diameter on an organic thin film. As an ultimate goal of fabrication to explore the future technology of atomic-level material processing, an atom guide using a hollow fiber and atom trapping by the illumination mode PSTM were proposed to control the thermal motion of freely dying atoms in vacuum. The concept of a virtual photon based on an intuitive modeling of the localized evanescent light was introduced to provide a semiclassical theory of the PSTM. Transfer functions of the PSTM were calculated by using this model, which agreed qualitatively with the experimental results. >
Impact of assembly, testing and launch operations on the airborne bacterial diversity within a spacecraft assembly facility clean-room

Abstract In an effort to minimize the probability of forward contamination of pristine extraterrestrial environments, the National Aeronautics and Space Administration requires that all US robotic spacecraft undergo assembly, testing and launch operations (ATLO) in controlled clean-room environments. This study examines the impact of ATLO activity on the microbial diversity and overall bioburden contained within the air of the clean-room facility in which the Mars Exploration Rovers (MERs) underwent final preparations for launch. Air samples were collected from several facility locations and traditional culture-based and molecular methodologies were used to measure microbial burden and diversity. Surprisingly, the greatest estimates of airborne bioburden, as derived from ATP content and cultivation assays, were observed prior to the commencement of MER ATLO activities. Furthermore, airborne microbial diversity gradually declined from the initiation of ATLO on through to launch. Proteobacterial sequences were common in 16S rDNA clone libraries. Conspicuously absent were members of the Firmicutes phylum, which includes the genus Bacillus. In previous studies, species of this genus were repeatedly isolated from the surfaces of spacecraft and clean-room assembly facilities. Increased cleaning and maintenance initiated immediately prior to the start of ATLO activity could explain the observed declines in both airborne bioburden and microbial diversity.
Undergraduate language programmes in England: A widening participation crisis

England has a language education crisis: fewer people are studying languages at school and university language programmes are closing. This study analyses data from the Universities and Colleges Admissions Service (UCAS), the UK admissions service for higher education. The study quantifies how entry tariff and socioeconomic background affect access to language degree programmes. The results show that (1) the number of students studying languages and number of languages offered correlate with entry tariff and (2) the probability of a university offering languages and probability of it offering a range of at least five languages correlate with entry tariff and the percentage of students from less privileged socioeconomic backgrounds. Thus a widening participation crisis is highlighted: while many young people are unable to access language degree programmes, a small proportion, with the highest tariffs, can choose from a range of at least five languages. To combat the crisis, a Widening Participation Languages Network has been launched, supporting universities offering languages at below-average entry tariffs.
Out of Plane Propagation of Electromagnetic Waves in a Two-dimensional Periodic Dielectric Medium

Abstract By the use of the plane wave method we have calculated the dispersion curves (photonic band structure) of electromagnetic waves propagating in a structure consisting of an infinite array of parallel, infinitely long, dielectric rods of arbitrary cross-section, characterized by a dielectric constant ea, embedded in a medium characterized by a dielectric constant eb, when the intersections of the axes of the rods with a perpendicular plane form a two-dimensional Bravais lattice. In contrast with earlier calculations of the photonic band structures of two-dimensional, periodic, dielectric structures, in the present work the electromagnetic waves are assumed to propagate out of the plane perpendicular to the rods. In numerical calculations we study a triangular lattice of air cylinders in a dielectric medium, which has recently been shown to possess a band gap common to waves of both E and H polarization for propagation in the plane perpendicular to the rods. The shifts of the edges of this absolute .
Electromagnetic ion cyclotron waves stimulated by modest magnetospheric compressions

The relationship between sudden impulses and enhancements or onset of Pc 1 at high-latitude ground stations is well established. It has been proposed that increased hot proton temperature anisotropy resulting from convection during magnetospheric compression is responsible for the enhancement in Pc 1 emissions via generation of electromagnetic ion cyclotron (EMIC) waves in the dayside outer equatorial magnetosphere (e.g., Olson and Lee, 1983). We use AMPTE/CCE magnetic field and particle data to test this suggestion. Compression-induced Pc 1 events are very common in the AMPTE/CCE data set: among isolated sudden ( 6 region, 47% are associated with EMIC wave onset at the satellite. Compressions energize particles via earthward convection, so the association of local Pc 1 onsets with compressions may be either a temporal effect or merely the result of inward transport to the spacecraft of plasma previously unstable to EMIC waves. EMIC waves occur 10-20% of the time in the outer magnetosphere, which is considerably less than the occurrence rate of Pc 1 with compressions, suggesting that convection alone does not account for compression Pc 1 onset. To test whether the plasma is more unstable to EMIC waves after compressions than before, the proton distribution (1-300 keV) measured at the peak of the compression is used together with an image dipole model to calculate the distribution that would result from adiabatic expansion back to the precompression state. Comparison of the EMIC wave growth rates from the measured compression and extrapolated expansion distributions provide an indication of the compression-induced enhancement of EMIC wave activity. Differences in wave growth of several orders of magnitude are found, indicating significant increases in EMIC wave activity. The results suggest that enhancements in dynamic pressure pump the energetic proton distributions in the outer magnetosphere, driving EMIC waves. Waves are expected to be generated most readily close to the magnetopause, and transient pressure pulses may be associated with bursts of EMIC waves, which would be observed on the ground in association with ionospheric transient signatures.
Itaconate Suppresses the Activation of Mitochondrial NLRP3 Inflammasome and Oxidative Stress in Allergic Airway Inflammation

Itaconate has emerged as a novel anti-inflammatory and antioxidative endogenous metabolite, yet its role in allergic airway inflammation (AAI) and the underlying mechanism remains elusive. Here, the itaconate level in the lung was assessed by High Performance Liquid Chromatography (HPLC), and the effects of the Irg1/itaconate pathway on AAI and alveolar macrophage (AM) immune responses were evaluated using an ovalbumin (OVA)-induced AAI model established by wild type (WT) and Irg1−/− mice, while the mechanism of this process was investigated by metabolomics analysis, mitochondrial/cytosolic protein fractionation and transmission electron microscopy in the lung tissues. The results demonstrated that the Irg1 mRNA/protein expression and itaconate production in the lung were significantly induced by OVA. Itaconate ameliorated while Irg1 deficiency augmented AAI, and this may be attributed to the fact that itaconate suppressed mitochondrial events such as NLRP3 inflammasome activation, oxidative stress and metabolic dysfunction. Furthermore, we identified that the Irg1/itaconate pathway impacted the NLRP3 inflammasome activation and oxidative stress in AMs. Collectively, our findings provide evidence for the first time, supporting the conclusion that in the allergic lung, the itaconate level is markedly increased, which directly regulates AMs’ immune responses. We therefore propose that the Irg1/itaconate pathway in AMs is a potential anti-inflammatory and anti-oxidative therapeutic target for AAI.
An efficient method for predicting wheel-rail forces in coupled nonlinear train-track-bridge system using artificial neural networks

Wheel-rail forces are an essential indicator for vehicle safety evaluation. The calculation of wheel-rail forces for the coupled nonlinear train-track-bridge system using the direct numerical integration method is time-consuming, hindering the timely safety and reliability assessment of train operations. In this paper, an efficient method based on the nonlinear autoregressive with exogenous input artificial neural network (NARX-ANN) was proposed to predict the nonlinear wheel-rail force of trains on bridges caused by track irregularity. Firstly, samples of track irregularity time history were randomly generated using the stochastic harmonic function method. The vertical and lateral wheel-rail forces of the coupled nonlinear train-track-bridge system were calculated by numerical integration. Secondly, the NARX-ANN model was established and trained with a small number of randomly selected wheel-rail force samples. Finally, the wheel-rail forces obtained by numerical integration were regarded as the ground truth to verify the prediction accuracy of the NARX-ANN model. The influence of training configuration, initial output, and the number of time delays on prediction accuracy was systematically analyzed. The results showed that the NARX-ANN model could accurately predict the time history of wheel-rail forces. In addition, its computational efficiency is 19.35 times higher than that of the numerical integration method. It is hoped that this study can guide the stochastic analysis of the train–track–bridge system.
EFFECT OF DIETARY SUPPLEMENTATION OF CLOVE, PEPPERMINT, CINNAMON OILS AND THEIR BLENDS ON GROWTH PERFORMANCE, CARCASS CHARACTERISTICS, BLOOD BIOCHEMICAL PARAMETERS AND ANTIOXIDANT STATUS OF BROILER CHICKS

The present study was conducted to evaluate the effect of dietary supplementation of clove, peppermint, cinnamon oils and their blends on growth performance, some blood biochemical constituents, antioxidants activities and economic efficiency. A total of 300unsexed (Ross – 308) broiler chicks, oneday old were fed from 1-35days on this specific dietary supplementation. Birds were divided randomly into five dietary treatment groups composed of 60 chicks per group, each in 3 replicates. The 1 group (control) received basal diet without additions, the 2, 3 and 4 groups received basal diet supplemented with clove, peppermint and cinnamon oils at0.3 g/kg diet of each, respectively and, the 5group received basal diet supplemented with blend of clove, peppermint and cinnamon oils at 0.1 g/kg diet of each. The results indicated that essential oils blend dietary supplementation significantly improved body weight, gain, feed conversion ratio, performance index in different periods of the experiment. Dressing, giblets and some immune organ percentages had higher values in the essential oil supplemented chicks than the control, while abdominal fat percentage had lower values in the essential oil supplemented chicks than the control . Broiler chicks fed the essential oil diet had greater serum total protein, glutathione (GPx) activities and high density lipoprotein (HDL)than those fed the control, however, significantly decreased serum cholesterol, triglycerides, low density lipoprotein (LDL) and lipid peroxidation (MDA) concentrations. In conclusion, beneficial effects of using blends of clove, peppermint and cinnamon oils at 0.1 g/ kg diet had been obtained on performance, blood biochemical and economical efficiency with no harm effect on health under experimental conditions.
Scattering from an abruptly terminated asymmetrical slab waveguide

The problem of the dominant TE guided-mode scattering from an abruptly terminated asymmetrical slab waveguide is examined by both the integral equation method and the variational technique. The reflection coefficient of the guided mode, the far-field radiation pattern, and the field distribution on the terminal plane are computed. Numerical results are presented for several cases of abruptly ended waveguides, including the three-layer guide and the structure with variable profile of the refractive index.
Electromagnetic inverse scattering: Retrievable information and measurement strategies

With reference to inverse scattering from an unknown object of limited extension embedded in a homogeneous background at a fixed frequency, we show that only a finite‐dimensional representation of the unknown contrast can be hopefully retrieved. Exploiting the quasi‐band‐limitedness property of scattered fields, an accurate upper bound to the dimension of such a space is evaluated in both the single incidence and multiview cases. Moreover, effective schemes are given to collect all the information available from the scattering experiments in a nonredundant manner. As a by‐product, an optimal (minimally redundant) sampling strategy for the monostatic radar cross section is also provided. Finally, we briefly discuss how the requirement for a globally effective and reliable solution scheme can lead to a reduction of the actually retrievable information.
Subnanosecond spectral diagnostics of streamer discharges: II. Theoretical background

In this second of two papers, we have developed a fully self-consistent method of diagnostics of streamer discharge plasmas based on the analysis of absolute intensities of the second positive (SPS) and first negative (FNS) systems of molecular nitrogen. The theory of the method combines a spectroscopic technique for the calculation of temporal waveforms of the nitrogen absolute SPS and FNS (0, 0)-band emission and a self-consistent semi-analytical parametric axially symmetric 1.5D model of the filamentary streamer head. The spectroscopic technique takes into account characterizations of all units of the measuring spectro-optical channel, including spatiotemporal resolution and resolution in wavelength. Also, chromatic aberrations of the focusing lighting lens, errors in the adjustment of the object image onto the input slit as well as the correction of the slit function at the non-uniformly illuminated input slit of the monochromator on width are taken into account. The model of the streamer head is characterized by some trial-consistent allowable parametric on-axis profile of the electric field combined with the electron and total space charge number density profiles fully self-consistent with each other and with the trial electric field. Additionally, the corresponding 2D configuration for the field and the electron number density is constructed via special ellipse-like geodesic lines. The absolute values and the synchronous ratio of the 1L spatially and time-resolved cross-correlated temporal waveforms of the SPS to the FNS (0, 0)-bands, the ratio of their altitudes and the total emission power for both the waveforms measured in paper I have been taken into account to reconstruct the 2D structure of the streamer head. With a procedure fitting the directly computed output voltage waveforms to the experimental ones, the peak values of the electric field and the electron number density within the streamer head at mid-gap distances have been found to be 430–500 Td and (2–3) × 1014 cm−3, respectively. And the corresponding absolute electric field is thus 70–80 kV cm−1 at the initial gas temperature within the repetitive streamer region of 450 K.
Efficient cycle time-throughput curve generation using a fixed sample size procedure

The cycle time-throughput curve is one of the most important analytical tools used to assess operating policies in manufacturing systems. Unfortunately, the generation of this curve is complicated and time consuming when generation is based upon extensive simulation analysis. This paper presents a simulation-based, fixed sample size strategy for generating a cycle time-throughput curve with minimal mean square error that mitigates the typical problems associated with a simulation-based cycle time-throughput curve. The strategy comprises two components, the sampling method and sampling weights. A queuing network of five workstations in series is used for validation of the approach. Results indicate that the sampling method using antithetic variates is effective in reducing the variance as well as bias of a cycle time-throughput curve. Furthermore, this method is robust to the sample size. Given a sufficiently large sample, the combination of common random numbers and antithetic variates is preferred. A reduction in the sample size and complexity of the system increases the significance of the sampling weights.
Power performance of PNP InAlAs/InGaAs HBTs

Recently, small-signal microwave performance has been reported for PNP InAlAs/InGaAs HBTs. While power performance of PNP AlGaAs/GaAs HBTs has been demonstrated, nothing has been reported on power performance of PNP HBTs in the InP material system. In this work, InAlAs/InGaAs PNP HBTs were fabricated and subsequently characterized under large signal conditions at X-band to determine their suitability for high-frequency power applications. PNP HBTs demonstrated f/sub T/ and f/sub max/ as high as 13 and 35 GHz, respectively. Power performance at 10 GHz was comparable to InP-based NPN single HBTs, providing up to 10 dB of gain, 0.49 mW//spl mu//sup 2/ of output power, and 24% power-added efficiency. Analysis of these HBTs suggests further design and epilayer optimizations for increased power performance.
Estimation for Discretely Observed Small Diffusions Based on Approximate Martingale Estimating Functions

Abstract. We consider an asymptotically efficient estimator of the drift parameter for a multi‐dimensional diffusion process with small dispersion parameter ɛ. In the situation where the sample path is observed at equidistant times k/n, k = 0, 1, …, n, we study asymptotic properties of an M‐estimator derived from an approximate martingale estimating function as ɛ tends to 0 and n tends to ∞ simultaneously.