Miracle-dz/UniFAR-FTUs huggingface dataset:
Enhanced Dipole-Dipole Interaction between Elementary Radiators Near a Surface

We report the results of elastic light-scattering measurements of random silver nanoparticle arrays fabricated onto structures supporting optical surface modes (i.e., surface plasmons or waveguide modes). We observe dramatic, qualitative changes in the resonance structure of the nanoparticle layer due to coupling with the propagating modes. The effect appears to arise because the underlying surface modes mediate an enhanced dipole-dipole interaction between individual nanoparticles. A calculation that supports this interpretation is described.
Precision and intelligent agricultural decision support system based on big data analysis

ABSTRACT In order to improve the effect of precision intelligent agricultural decision support system, this paper combines big data technology to carry out precision mining of agricultural data, and combines decision tree algorithm to carry out data classification processing. Moreover, this paper obtains the most effective agricultural decision reference data through data mining, combines the agricultural decision support process to set the functional modules of the decision system, and analyzes the implementation process of each functional module. In addition, this paper studies the theoretical basis and key technologies of the agricultural production structure optimisation decision support system, and builds a precision and intelligent agricultural decision support system based on big data analysis. The system mainly performs accurate processing of agricultural data and makes effective predictions, and then makes scientific decision results. Finally, this paper verifies the structure of the model in this paper combined with experimental analysis. From the comparison of experiments, it can be seen that the precision and intelligent agricultural decision support system constructed in this paper has significant effects.
Optical gain in silicon nanocrystals: Current status and perspectives

The article presents a short overview of the worldwide experimental activity directed towards vindicating the occurrence of positive optical gain in dense assemblies of luminescent silicon nanocrystals. In spite of an intense interest in the field, the achieved results are non‐uniform till now. Hints how to proceed further are given.
Towards a General Approach for Bat Echolocation Detection and Classification

Acoustic monitoring is an effective and scalable way to assess the health of important bioindicators like bats in the wild. However, the large amounts of resulting noisy data requires accurate tools for automatically determining the presence of different species of interest. Machine learning-based solutions offer the potential to reliably perform this task, but can require expertise in order to train and deploy. We propose BatDetect2, a novel deep learning-based pipeline for jointly detecting and classifying bat species from acoustic data. Distinct from existing deep learning-based acoustic methods, BatDetect2’s outputs are interpretable as they directly indicate at what time and frequency a predicted echolocation call occurs. BatDetect2 also makes use of surrounding temporal information in order to improve its predictions, while still remaining computationally efficient at deployment time. We present experiments on five challenging datasets, from four distinct geographical regions (UK, Mexico, Australia, and Brazil). BatDetect2 results in a mean average precision of 0.88 for a dataset containing 17 bat species from the UK. This is significantly better than the 0.71 obtained by a traditional call parameter extraction baseline method. We show that the same pipeline, without any modifications, can be applied to acoustic data from different regions with different species compositions. The data annotation, model training, and evaluation tools proposed will enable practitioners to easily develop and deploy their own models. BatDetect2 lowers the barrier to entry preventing researchers from availing of effective deep learning bat acoustic classifiers. Open source software is provided at: https://github.com/macaodha/batdetect2
Can suitability indices predict plant growth in the invaded range? The case of Acacias species

Forestry in many parts of the world depends on exotic species, making this industry a source of invasions in some countries. Among others, plantations of the genus Pinus, Eucalyptus, Acacia, Populus, and Pseudotsuga underpin the forestry industry and are a vital component of many countries economies. Among woody plants, the cosmopolitan genus Acacia includes some of the most commonly planted trees worldwide. In order to prevent, manage and control invasive plant species, one of the most used tools is species distribution models. The output of these models can also be used to obtain information about population characteristics, such as spatial abundance patterns or species performance. Although ecological theory suggests a direct link between fitness and suitability, this link is often absent. The reasons behind the lack of this relationship are multiple. Chile is one of the countries where Acacia species, in particular, A. dealbata and A. melanoxylon, have become invaders. Here, we used climatic and edaphic variables to predict the potentially suitable habitats for A. dealbata and A. melanoxylon in continental Chile and evaluate if the suitability indices obtained from these models are associated with the observed performance of the trees along the country. Our models show that variable importance showed significant similarities between the variables that characterize each species’ niche. However, despite the high accuracy of our models, we did not observe an association between suitability and tree growth. This disconnection between suitability and performance can result from multiple causes, from structural limitations, like the lack of biotic interactions in the models, to methodological issues, like the usefulness of the performance metric used. Whatever the scenario, our results suggest that plans to control invasive species should be cautious in assuming this relationship in their design and consider other indicators such as species establishment success.
Ligand Gaussian accelerated molecular dynamics 2 (LiGaMD2): Improved calculations of ligand binding thermodynamics and kinetics with closed protein pocket

Ligand binding thermodynamics and kinetics are critical parameters for drug design. However, it has proven challenging to efficiently predict ligand binding thermodynamics and kinetics from molecular simulations due to limited simulation timescales. Protein dynamics especially in the ligand binding pocket often plays an important role in ligand binding. Based on our previously developed Ligand Gaussian accelerated molecular dynamics (LiGaMD), here we present LiGaMD2 in which a selective boost potential was applied to both the ligand and protein residues in the binding pocket to improve sampling of ligand binding and dissociation. To validate the performance of LiGaMD2, the T4 lysozyme (T4L) mutants with open and closed pockets bound by different ligands were chosen as model systems. LiGaMD2 could efficiently capture repetitive ligand dissociation and binding within microsecond simulations of all T4L systems. The obtained ligand binding kinetic rates and free energies agreed well with available experimental values and previous modeling results. Therefore, LiGaMD2 provides an improved approach to sample opening of closed protein pockets for ligand dissociation and binding, thereby allowing for efficient calculations of ligand binding thermodynamics and kinetics.
Replitrons: a new group of eukaryotic transposons encoding HUH endonuclease

HUH endonucleases of the Rep (replication protein) class mediate the replication of highly diverse plasmids and viral genomes across all domains of life. Reps also function as transposases, and three evolutionarily independent groups of transposable elements (TEs) mobilised by Reps have been described: the prokaryotic insertion sequences IS200/IS605 and IS91/ISCR, and the eukaryotic Helitrons. Here I present Replitrons, a new group of eukaryotic transposons encoding Rep HUH endonuclease. Replitron transposases feature Rep with one catalytic Tyr (Y1) as their only recognised domain, contrasting with Helitron transposases that feature Rep with two Tyr (Y2) and a fused helicase domain (i.e. RepHel). Protein clustering found no link between Replitron transposases and described Rep transposases, and instead recovered a weak association with Reps of circular Rep-encoding single stranded (CRESS) DNA viruses and their related plasmids (pCRESS). The predicted tertiary structure of the transposase of Replitron-1, the founding member of the group that is active in the green alga Chlamydomonas reinhardtii, closely resembles that of CRESS-DNA viruses and other HUH endonucleases. Replitrons are present in at least three eukaryotic supergroups and reach high copy numbers in non-seed plant genomes. Replitron DNA sequences generally feature short direct repeats at, or potentially near, their termini. Finally, I characterise copy-and-paste de novo insertions of Replitron-1 using long-read sequencing of C. reinhardtii experimental lines. Overall, these results support an ancient and evolutionarily independent origin of Replitrons, in line with other major groups of eukaryotic TEs. This work substantially expands the known diversity of both transposons and HUH endonucleases in eukaryotes.
Multiple pathways for reestablishing PAR polarity in C. elegans embryo

Asymmetric cell divisions, where cells divide with respect to a polarized axis and give rise to daughter cells with different fates, are critically important during development. In many such divisions, the conserved PAR polarity proteins accumulate in distinct cortical domains in response to a symmetry breaking cue. The one-cell C. elegans embryo has been a paradigm for understanding mechanisms of PAR polarization, but much less is known about polarity reestablishment during subsequent divisions. Here, we investigate the polarization of the P1 cell of the two-cell embryo. A posterior PAR-2 domain forms in the first four minutes of the birth of P1, and polarization becomes stronger over time. Initial polarization depends on the PKC-3 and PAR-1 kinases. However, in par-1 mutants, delayed polarization can occur, at a time when centrosome-associated AIR-1 is near the posterior cortex and myosin flows towards the anterior. Loss of myosin and par-1 function together results in more severe polarity defects. Based on these and other results, we propose that PAR polarity in the P1 cell is generated by at least two redundant mechanisms: There is a novel early pathway dependent on PAR-1, PKC-3 and cytoplasmic polarity, and a late pathway that resembles symmetry breaking in the one-cell embryo and requires myosin flow and PKC-3.
Development Characteristics and Dynamic Structure of Tropical Intraseasonal Convection Anomalies

Abstract The development and dynamical structure of intraseasonal low-frequency convection anomalies in the equatorial region are investigated using 10 years (1975–85) of outgoing longwave radiation (OLR) and 7 years (1979–85) of 200 and 850 mb wind data. The composite OLR anomalies for 36 cases show a four-stage development process: initiation over equatorial Africa, rapid intensification when passing through the Indian Ocean, mature evolution characterized by a weakening in the maritime continent and redevelopment over the western Pacific, and dissipation near the date line in moderate events or emanation from the equator toward North America and southeastern Pacific in strong events. A noticeable feature in vertical structure is that the 850 mb convergence leads convection and midtropospheric upward motion by about 30 degrees longitude in both developing and mature phases. Equatorial upper- (lower-) level easterly (westerly) anomalies and associated twin anomalous anticyclonic (cyclonic) circulation an.
Personal Identification by Fusing Hand Shape Geometry and Palmprint Features

This paper presents a new personal identification approach with fusion of hand shape geometry and palmprint features based on Gabor wavelet transformation. Two kinds personal features can be extracted form the low-resolution hand images. Hand shape geometry features include length of four fingers and width of palm. The palmprint features are composed of principal lines, wrinkles, minutiae, delta points. In pattern matching, the normalization method of matching degree is proposed. At the same time square difference distance is used to calculate feature matching degree of the hand shape geometry and palmprint. The result of experiment show that this approach is the most suitable, acceptable and the higher recognition rate, respectively, using different feature extraction methods.
Theory of speckle dependence on surface roughness

The theory of speckle in partially coherent, monochromatic light is extended to cover the entire range of object roughness. For “almost white-noise” objects it is shown how the speckle statistics are related to a Gaussian approximation of the object statistics. Within this approximation, general relations are derived for the spatial speckle correlation and the spatial Wiener spectrum. The theory is applied to calculate rms speckle contrast as function of object roughness, coherence of the illumination, and receiver plane defocusing.
Transport properties in FeSe0.5Te0.5 nanobridges

FeSeTe nanobridges of different widths have been fabricated on MgO substrates using focused ion beams. These nanobridges exhibit the Josephson effects. The current-voltage curves of junctions with 248–564 nm wide follow the resistively and capacitatively shunted junction model. Shapiro steps under microwave radiation were clearly observed in these nanobridges. The products of the critical current and normal state resistance (IcRn) are remarkably high. The temperature dependence of IcRn product followed the Ambegaokar-Baratoff (A-B) relation. The value of energy gap of FeSeTe calculated from the A-B relation is 3.5kBTc. The nanobridge junctions have a strong potential for high frequency applications.
Fast unsupervised texture segmentation using Texel similarity map

Unsupervised texture segmentation is a challenging topic in computer vision. It is difficult to obtain boundaries of texture regions automatically in real-time, especially for cluttered images. This paper presents a new fast unsupervised texture segmentation method. First, the Texel similarity map (TSM) is used to compare the changes of intensity and gray level of neighboring pixels to determine whether they are identical. Then, a scheme called multiple directions integral images (MDII) is proposed to quickly evaluate the TSM. With the aid of MDII, one pixel’s similarity value can be computed in constant time. Finally, the proposed segmentation method is tested on both artificial texture and natural images. Experimental results show that the proposed method performs well on a wide range of images, and outperforms state-of-the-art method on segmentation speed.
A Model for the Declining Rotation Curves of Cluster Spiral Galaxies

Recent numerical studies have shown that mean tidal fields in clusters of galaxies can cause a significant increase in the planar velocity dispersions of stars and gas clouds in the disks of spiral galacies. Since the perturbations caused by cluster tidal fields are generally weak and fairly symmetric, the stellar distributions of the perturbed galaxies would not necessarily show obvious signs of tidal disturbance. In this paper it is shown that te increased noncircular velocities of stars can result in a symmetric decline (at large radii) of the rotation curves of tidally perturbed spiral galaxies in clusters. This decline results from the well-known phenomenon of the 'asymmetric drift' of a high velocity dispersion stellar population. This suggests that the observations of the decline rotation curves of spiral galaxies in clusters do not necessarily imply that their dark matter halos have been tidally truncated as in generally assumed.
Extensive and anomalous grounding line retreat at Vanderford Glacier, Vincennes Bay, Wilkes Land, East Antarctica

Abstract. Wilkes Land, East Antarctica, has been losing mass at an accelerating rate over recent decades in response to enhanced oceanic forcing. Overlying the Aurora Subglacial Basin, it has been referred to as the “weak underbelly” of the East Antarctic Ice Sheet and is drained by several major outlet glaciers. Despite their potential importance, few of these glaciers have been studied in detail. This includes the six outlet glaciers which drain into Vincennes Bay, a region recently discovered to have the warmest intrusions of modified Circumpolar Deep Water (mCDW) ever recorded in East Antarctica. Here, we use satellite imagery; differential synthetic aperture radar interferometry (DInSAR); and remotely sensed datasets of ice-surface velocity, ice-surface elevation and grounding line position to investigate ice dynamics between 1963 and 2022. Our results support previous observations of extensive grounding line retreat at Vanderford Glacier, measured at 18.6 km between 1996 and 2020. The persistent grounding line retreat, averaging 0.8 km yr−1, places Vanderford Glacier as the fastest retreating glacier in East Antarctica, and the third fastest in Antarctica, across decadal timescales. Such rapid retreat is consistent with the hypothesis that warm mCDW is able to access deep cavities formed below the Vanderford Ice Shelf, driving high rates of basal melting close to the grounding line. With a retrograde slope observed inland along the Vanderford Trench, such oceanic forcing may have significant implications for the future stability of Vanderford Glacier.
On Local Approximation Properties of L2-Projection on Spline-Subspaces†

For L2 approximations in an intervel I and a sequences by'local approximation properties' is meant whether a high regularity of the approximated function in i'will give a corresponding small error in the l2sence for proper subintervals I" of I'. Whereas this is not so for the Fourier-sums, it holds true for projections on subspaces fulfilling certain approximability conditions which are typical for splines.
The Mechanism of Spark Discharge in Air at Atmospheric Pressure. I

The Townsend equation for the passage of a spark is analyzed and its inadequacy for explaining sparks in air at near atmospheric pressures is demonstrated. The mechanisms active in air at higher pressures, viz., the electron avalanche and its tip field, photo‐ionization in the gas and positive streamer formation are presented. A quantitative criterion for streamer formation is applied to give a quantitative theory for spark breakdown in air at atmospheric pressures. The theory gives quantitative agreement with experiment and predicts departures from Paschen's law. At values of the product, pressure times gap length less than 200 mm×cm in air, the new mechanism is unimportant. The theory is applied to longer sparks at atmospheric pressures and the effect of the decrease in density of photo‐ionization in longer avalanches considered. This leads to a modification of the Meek mechanism by which the electron avalanche slows down while a retrograde positive streamer moves at high speed to the cathode and then a.
Generation of three-dimensional patterns through wave interaction in a model of free surface swirling flow

The free surface flow in a cylindrical tank over a rotating bottom is known to support spectacular three-dimensional patterns, including deformation of the inner free surface into the shape of rotating polygons and sloshing behavior of the upper free surface (e.g. Iga et al 2014 Fluid Dyn. Res. 46 031409). Through a stability analysis of a simplified model of this flow, we show that such patterns can be explained as a resonance mechanism involving different families of waves. The approach extends a previous work (Tophøj et al 2013 Phys. Rev. Lett. 110 194502) which explained the rotating polygons as an interaction between gravity waves and centrifugal waves, under the assumption that the base flow can be modeled as a potential vortex. We show that this previous model is justified for strong rotation rates (Dry-Potential case), and that for weaker rotations it can be improved by introducing an inner vortex core in solid-body rotation, which either extends to the center of the plate (Wet case) or surrounds a dry central region (Dry-Composite case). The study of this improved model predicts two new kinds of instabilities. The first occurs at low rotations (Wet case) and results from an interaction between gravity waves and the Kelvin–Kirchhoff wave (namely, oscillation of the boundary of the vortex core). This instability is proposed to be at the origin of the sloshing phenomenon. The second new instability occurs, for moderate rotations, (Dry-Composite case) as an interaction between gravity waves and a ‘Kelvin-Centrifugal’ wave characterized by deformation of the inner surface and the vortex core boundary in opposite directions. This instability exists for all azimuthal wave numbers starting from m = 1, this case corresponding to a ‘monogon’ pattern.
The (s, Q) inventory model with Erlang lead time and deterministic demand

We develop a simple, approximately optimal solution to a model with Erlang lead time and deterministic demand. The method is robust to misspecification of the lead time and has good accuracy. We compare our approximate solution to the optimal for the case where we have prior information on the lead‐time distribution, and another where we have no information, except for computer‐generated sample data. It turns out that our solution is as easy as the EOQ's, with an accuracy rate of 99.41% when prior information on the lead‐time distribution is available and 97.54–99.09% when only computer‐generated sample information is available. Apart from supplying the inventory practitioner with an easy heuristic, we gain insights into the efficacy of stochastic lead time models and how these could be used to find the cost and a near‐optimal policy for the general model, where both demand rate and lead time are stochastic. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004
Experiment system of thin-mirror active optics

In this system, the experiment mirror has 500 mm aperture and 6 mm thickness. There are 58 actuators and three fixed points in it. A Shack-Hartmann test apparatus is used for the measurement of wavefront aberration. In this apparatus an ingenious equivalent of lenslet array is used. All image points formed by it appear very clear theoretical diffraction pattern. And a CCD from a TV camera is used. Like European Southern Observatory, we use quasi-Zernike polynomial to fit the wavefront aberration for correcting. But in our work correction is to the whole wavefront aberration (except lateral focus and longitudinal focus). In our work, another important character is that the damp least square method is used for determining the forces. The correction results are the root mean square of wavefront aberration about 0.02 - 0.04 micrometers . A circle including measuring and correcting the wavefront aberration takes about 3.3 minutes. A more precise algorithm proposed by us is used for calculating the wavefront aberration for checking.