Miracle-dz/UniFAR-FTUs huggingface dataset:
Two Fabry-Perot interferometers for high precision wavelength calibration in the near-infrared

The most frequently used standard light sources for spectroscopic high precision wavelength calibration are hollow cathode lamps. These lamps, however, do not provide homogeneous line distribution and intensities. Particularly in the infrared, the number of useful lines is severely limited and the spectrum is contaminated by lines of the filler gas. With the goal of achieving sub m/s stability in the infrared, as required for detecting earthlike extra-solar planets, we are developing two passively stabilized Fabry-Perot interferometers for the red visible (600-1050nm) and near infrared wavelength regions (900-1350nm). Each of the two interferometers can produce ~15,000 lines of nearly constant brightness. The Fabry-Perot interferometers aim at a RV calibration precision of 10cm/s and are optimized in line shape and spacing for the infrared planet hunting CARMENES spectrograph that is currently being built for the Calar Alto 3.5m telescope. Here we present the first results of our work.
Finite phased array of microstrip patch antennas: the infinite array approach

An efficient method of analysis of large infinite arrays based on a convolution technique that allows one to obtain the finite array characteristics from the infinite array results is presented. The edge effects are taken into account by convoluting the infinite array results with the proper current amplitude window on the array. The method is based on the use of Poisson's sum formula in the case of finite arrays applied here to microstrip antennas. It is an approximate technique that can be assimilated into a perturbation method. >
The complete mitochondrial genome of a fouling mussel, Xenostrobus atratus (Mollusca: Mytilidae), and its phylogenetic implication

Abstract In this study, we report the female-lineage mitochondrial genome of Xenostrobus atratus for the first time. The circular mitochondrial genome is 14,806 bp in length and contains 12 protein-coding genes, 22 transfer RNA genes, and two ribosomal RNA genes. All genes are encoded on the heavy strand. The genome composition is A + T biased (66.6%), with 25.2% A, 41.4% T, 21.7% G and 11.7% C. A Bayesian inference (BI) phylogenetic tree was constructed based on the mitochondrial genomes of X. atratus and 46 other Mytilidae species. Our results demonstrate that X. atratus and Limnoperna fortunei have distinct lineages, opposing synonymizing Xenostrobus within Limnoperna. According to this study, the validity of the subfamily Limnoperninae and genus Xenostrobus is strongly supported. However, there is still an urgent need for more mitochondrial data to decide to which subfamily X. atratus belongs.
Characterization of the mitochondrial genome of the lawn cutworm Spodoptera depravata (Lepidoptera: Noctuidae)

Abstract The lawn cutworm, Spodoptera depravata, is one of the most important pests that causes economic damage to grass crops. This study reports the complete mitochondrial genome of an S. depravata sample collected in China. The genome is a circular molecule 15,460 bp in length with an overall A + T content of 81.6%. It contains 13 protein-coding genes, 22 transfer RNA genes, and two ribosomal RNA genes. The gene content and organization of the mitogenome of S. depravata are identical to those of other Spodoptera species. Maximum-likelihood phylogenetic analysis based on mitogenomes showed a close evolutionary relationship between S. depravata and S. exempta. This study provides new molecular data for the identification and further phylogenetic analyses of Spodoptera species.
Latent Space Models for Dynamic Networks

Dynamic networks are used in a variety of fields to represent the structure and evolution of the relationships between entities. We present a model which embeds longitudinal network data as trajectories in a latent Euclidean space. We propose Markov chain Monte Carlo (MCMC) algorithm to estimate the model parameters and latent positions of the actors in the network. The model yields meaningful visualization of dynamic networks, giving the researcher insight into the evolution and the structure, both local and global, of the network. The model handles directed or undirected edges, easily handles missing edges, and lends itself well to predicting future edges. Further, a novel approach is given to detect and visualize an attracting influence between actors using only the edge information. We use the case-control likelihood approximation to speed up the estimation algorithm, modifying it slightly to account for missing data. We apply the latent space model to data collected from a Dutch classroom, and a cosponsorship network collected on members of the U.S. House of Representatives, illustrating the usefulness of the model by making insights into the networks. Supplementary materials for this article are available online.
Disentangling the Impact of Event‐ and Annual‐Scale Precipitation Extremes on Critical‐Zone Hydrology in Semiarid Loess Vegetated by Apple Trees

The extent and mechanisms by which precipitation extremes affect hydrological processes in the critical zone (CZ) of loess possessing a thick unsaturated zone remains poorly understood. To this end, we here employed a coupled liquid‒vapor‒heat‒airflow STEMMUS (simultaneous transfer of energy, mass, and momentum in unsaturated soil) model to investigate the impact of extreme precipitation, at both event and annual scales, on CZ hydrological processes within a semiarid loess site vegetated by apple trees on China's Loess Plateau. At the event scale, the vapor flux was two orders of magnitude lower than the liquid water flux. However, the thermal vapor flux penetrated to depths of 200 cm, whereas the isothermal liquid water flux only infiltrated to 100 cm during the study period, implying that thermal‐gradient‐driven vapor transfer is an important mechanism for deep‐layer recharge (DLR). At the annual scale, the DLR below 200 cm during extremely wet years was 6.5 times larger than that during extremely dry years. In contrast, extreme changes in climate had only limited impacts on evapotranspiration; the difference between extremely wet and extremely dry years averaged only 35 mm, much less than the difference in precipitation, which averaged 310 mm. However, the extremely dry years showed a higher ratio (0.58) between transpiration and evapotranspiration than did the extremely wet years (0.51). The findings reported here improve our understanding of CZ hydrological processes related to precipitation extremes in semiarid loess regions.
The Biserial-Phi Correlation Coefficient

ABSTRACT The correlation coefficient appropriate in a fourfold situation resulting from the crossing of two dichotomous variables depends on whether the dichotomies are true or arbitrary. Almost all sources dealing with the fourfold situation discuss only the pure cases (both dichotomies true or both dichotomies arbitrary). The mixed case (one dichotomy true and the other arbitrary), introduced at least four decades ago and accompanied in more than one source with the wrong formula for the coefficient, is reintroduced in this study. In addition, a correction for unequal sample size respecting the true dichotomy is presented.
The optical spectrum of the young planetary nebula Hubble 12

The remarkable young compact planetary nebula, Hubble 12, renowned for its extended envelope, which radiates the lines of molecular hydrogen excited by fluorescence, has a dense core of complex structure. We present high dispersion measurements of the spectrum from 366 to 1005 nm: if the emission lines of [N II], [0 Ill] and [S III] originate in the same strata, the diagnostics suggest a zone with an electron density of 500 000 cm -3, and Tt 13 600 K, but lower densities and temperatures are indicated by the auroral/nebular line ratios of other emissions such as those of [0 II], [ S II] and the nebular line ratios of [Cl Ill], [ Ar IV] and especially [N I]. The chemical composition of Hubble 12 is hard to establish, because of the great range in density and temperature of the emitting layers. We discuss arguments for and against the progenitor star as an oxygenor metal-deficient object. A newly developed density-contrast theoretical model is applied to this bipolar object, but a convincing theoretical model must await optical monochromatic images of high spatial resolution.
Acceleration of cosmic rays by shock waves

Theoretical work on various processes by which shock waves accelerate cosmic rays is reviewed. The most efficient of these processes, Fermi acceleration, is singled out for special attention. A linear theory for this process is presented. The results found on the basis of nonlinear models of Fermi acceleration, which incorporate the modification of the structure caused by the accelerated particles, are reported. There is a discussion of various possibilities for explaining the generation of high-energy particles observed in interplanetary and interstellar space on the basis of a Fermi acceleration mechanism. The acceleration by shock waves from supernova explosions is discussed as a possible source of galactic cosmic rays. The most important unresolved questions in the theory of acceleration of charged particles by shock waves are pointed out.
Stability of native defects in hexagonal and cubic boron nitride

We investigate, through first-principles calculations, the stability and electronic structure of self-interstitials and vacancies in both hexagonal (graphite-like) and cubic boron nitride. We find that the self-interstitials ${\mathrm{N}}_{i}$ and ${\mathrm{B}}_{i}$ in hexagonal boron nitride $(h\ensuremath{-}\mathrm{BN})$ have low formation energies, comparable to those of the vacancies ${V}_{\mathrm{N}}$ and ${V}_{\mathrm{B}}. $ For instance, we find that ${\mathrm{N}}_{i}$ is the most stable defect in $h\ensuremath{-}\mathrm{BN}$ under N-rich and p-type conditions followed by the nitrogen vacancy. This is consistent with experimental findings of large concentrations of nitrogen interstitials and vacancies, and of the trapping of nitrogen in the hexagonal phase of BN thin films grown by ion-bombardment assisted deposition techniques. In contrast, in cubic boron nitride $(c\ensuremath{-}\mathrm{BN})$ the self-interstitials have high formation energies as compared to those of the vacancies. As a consequence, the formation of vacancy-interstitial pairs in kickout processes would typically require much more energy in $c\ensuremath{-}\mathrm{BN}$ than in $h\ensuremath{-}\mathrm{BN}. $ This suggests that a possible role of the ion bombardment in favoring the growth of $c\ensuremath{-}\mathrm{BN}$ films is to generate a much larger amount of defects in the hexagonal phase than in the cubic phase.
Direct measurement of the effective input noise power of an optical parametric amplifier

The spontaneous fluorescence background in optical parametric amplifiers is generally attributed to the zero‐point fluctuations of the electromagnetic field. These are amplified in parallel to the seed light and lead to an uncompressible superfluorescence background that deteriorates the contrast in optical parametric chirped pulse amplifiers (OPCPA). The absolute level of the underlying parametric fluorescence has not been reported so far. Comparing the fluorescence to low level cw seed light and quantitatively monitoring the output of a noncollinear optical parametric amplifier for both sources, the level is now determined. In a situation of 50 nm visible output bandwidth and low Gaussian spatial modes about 58 photons are found in the signal direction within the femtosecond time window of the amplifier. The superfluorescence level is observed to be proportional to the pump area for constant signal amplification. The implications for the background in high power OPCPA are discussed.
Magnetic ordering of Fe and Tb in the ab initio determined Fe R Ge 2 O 7 structure ( R = Y , Tb)

The crystal structure of $\mathrm{Fe}R{\mathrm{Ge}}_{2}{\mathrm{O}}_{7}$ ($R=\mathrm{Y}$, Tb) has been solved ab initio from x-ray powder diffraction data. It is monoclinic, space group ${P2}_{1}/m$ (No. 11), $Z=4,$ $a$ (\AA{})=9.6552(4) and 9.6388(8); $b$ (\AA{})=8.5197(3) and 8.4789(7), $c$ (\AA{})=6.6746(3) and 6.7383(5), \ensuremath{\beta} (\ifmmode^\circ\else\textdegree\fi{})=100.761(2) and 100.377(4), and $V({\AA{}}^{3})=539.39$ and 541.69, for $R$=Y and Tb, respectively. Precise oxygen positions were determined for the Tb compound from a room temperature neutron diffraction profile, refined by the Rietveld method to an ${R}_{f}=3.99%$ using 58 parameters. The ${\mathrm{FeYGe}}_{2}{\mathrm{O}}_{7}$ crystal structure contains three kinds of coordination polyhedra: ${R}^{3+}$ coordinated to seven oxygens at slightly different lengths forming a capped octahedron, ${\mathrm{FeO}}_{6}$ distorted octahedra, and four types of ${\mathrm{GeO}}_{4}$ tetrahedra. Its most interesting feature is the existence of flattened chains of $R{\mathrm{O}}_{7}$ polyhedra linked in the $c$ direction through pairs of ${\mathrm{FeO}}_{6}$ octahedra with which they share edges, forming layers running parallel to the $\mathrm{bc}$ crystal plane. Magnetization measurements between 350 and 1.7 K show one peak at 38 K for $R$=Y and two maxima at 42 and 20 K for the Tb compound, which could indicate transitions to antiferromagnetically ordered states. From low-temperature neutron diffraction data on ${\mathrm{FeTbGe}}_{2}{\mathrm{O}}_{7},$ three-dimensional antiferromagnetic ordering is established, both Fe and Tb sublattices getting simultaneously ordered at ${T}_{N}=42\mathrm{K}. $ The propagation vector of the magnetic structure is $k=[0,0,0]. $ At 1.7 K the magnetic moments $3.91(7){\ensuremath{\mu}}_{B}$ $({\mathrm{Fe}}^{3+})$ and $7.98(6){\ensuremath{\mu}}_{B}$ $({\mathrm{Tb}}^{3+})$ lie ferromagnetically coupled in the $\mathrm{ac}$ planes, which contain ${\mathrm{TbO}}_{7}{\ensuremath{-}\mathrm{F}\mathrm{e}\mathrm{O}}_{6}{\ensuremath{-}\mathrm{T}\mathrm{b}\mathrm{O}}_{7}$- chains in the $c$ direction, forming relatively small angles with the $c$ axis. The coupling between parallel $\mathrm{ac}$ planes is antiferromagnetic along the $b$ direction. This model leads to a best fit of ${R}_{\mathrm{mag}}=3.02%. $ The thermal evolution of the magnetic moments suggests that below \ensuremath{\sim}20 K the faster increase of the ${\mathrm{Tb}}^{3+}$ moments is due to the stronger Fe-Tb interactions and crystal field effects. The maximum in $\ensuremath{\chi}(T)$ at 20 K does not correspond then to any phase transition, but is caused by the exchange interaction with the ordered iron subsystem.
Molecular Genetic Identification of Some Sweet Sorghum - Sorghum bicolor L. (Ankolib) Accessions - Sudan

This study is an attempt to identify some Sudanese Sweet Sorghum (Ankolib) [Sorghum bicolor (L.) Moench. ] accessions using two types of DNA-based markers: RAPD and SSR. Seven (Ankolib) accessions were assayed, namely: Black Ankolib, Black White Ankolib, Dark Red Ankolib, Red Yellow Ankolib, White Ankolib, White Black Ankolib and Bengaga. All of the accessions were uniquely identified and fingerprinted. The levels of polymorphism among the accessions as revealed by (22) RAPD primers and (16) SSR primer pairs were (58%) and (76%) respectively, indicating that SSRs markers were highly polymorphic. The scored data of the two markers were analyzed using the Dice Coefficient to assess genetic relationships among the (7) (Ankolib) accessions. The results of the statistical analysis revealed that the accession Bengaga was distantly related to the other (6) accessions which all showed a close genetic similarity among them. UPGMA cluster analysis generated a dendrogram for each marker alone and for the combined data of the two markers. It was observed that in all of the dendrogram the accession Bengaga was found in a unique cluster thus indicating its uniqueness, since it is the only accession that has seeds that produce flour besides its juicy sweet stem.
Laser-assisted elastic electron-atom collisions

The authors analyse the 'elastic' scattering, accompanied by the transfer of l photons, of fast electrons by atoms in the presence of a strong laser field. They focus their attention on the region of small momentum transfers, where the 'dressing' effect due to the dipole distortion of the target by the laser field is shown to produce important modifications of the differential cross section. Detailed calculations are presented for both atomic hydrogen and helium targets at an incident electron energy of 100 eV and for various geometrical configurations.
WISE AND AKARI

The first all-sky mid-/far-infrared survey by IRAS in the 1980s, has been followed by only two more, by AKARI, from 2006, and WISE in 2010. I discuss some features of the WISE survey, and highlight some key results from early extragalactic observations that have been made by the science team during the operation of the telescope, and the post-operation proprietary period during which the public release data products were being generated. The efficient survey strategy and very high-data rate from WISE produced a catalogue of 530 million objects that was released to the public in March 2012. The WISE survey strategy naturally provided the deepest coverage at the ecliptic poles, where matched comparison fields were obtained using Spitzer, and where AKARI also observed deep fields. I describe some of the follow-up work that has been carried out based on the WISE survey, and the prospects for enhancing the WISE data by combining the AKARI survey results are also discussed. While the all-sky AKARI survey is less deep than the WISE catalogue, and is still being worked on by the AKARI science team, it includes a larger number of bands, extends to longer wavelengths, and in particular has very complementary band passes to WISE in the mid-infrared waveband, which will provide enhanced spectral information for relatively bright targets.
New results from the low-frequency counterpart of the XMM large scale structure survey

The XMM Large Scale Structure survey (XMM-LSS) is an X-ray survey aimed at studying the large scale structure of the Universe. The XMM-LSS field is currently being followed up using observations across a wide range of wavelengths, and in this paper we present the observational results of a low frequency radio survey of the XMM-LSS field using the Very Large Array at 74 and 325 MHz. This survey will map out the locations of the extragalactic radio sources relative to the large scale structure as traced by the X-ray emission. This is of particular interest because radio galaxies and radio loud AGN show strong and complex interactions with their small and larger scale environment, and different classes of radio galaxies are suggested to lie at different places with respect to the large scale structure. For the phase calibration of the radio data, we used standard self-calibration at 325 MHz and field-base calibration at 74 MHz. Polyhedron-based imaging as well as mosaicing methods were used at both frequencies. At 74 MHz we have a resolution of $30''$, a median $5\sigma$ sensitivity of $\sim162$ mJy/beam and we detect 666 sources over an area of 132 square degrees. At 325 MHz, we have a resolution of $6.7''$, a median $5\sigma$ sensitivity of 4 mJy/beam, and we detect 847 sources over an area of 15.3 square degrees. At 325 MHz we have detected a region of diffuse radio emission which is a cluster halo or relic candidate.
Bistable systems: Master equation versus Fokker-Planck modeling

Relaxation and fluctuations of nonlinear macroscopic systems, which are frequently described by means of Fokker-Planck or Langevin equations, are studied on the basis of a master equation. The problem of an approximate Fokker-Planck modeling of the dynamics is investigated. A new Fokker-Planck modeling is presented which is superior to the conventional method based on the truncated Kramers-Moyal expansion. The new approach is shown to give the correct transition rates between deterministically stable states, while the conventional method overestimates these rates. An application to the Schl\"ogl models for first- and second-order nonequilibrium phase transitions is given.
Radiative transfer in a clumpy medium – I. Analytical Markov-process solution for an N-phase slab

The equation for the transfer of continuum photons in a multiphase scattering medium, which obeys Markov mixing statistics, is solved for an externally illuminated slab geometry. The slab is assumed to consist of N distinct phases containing dust grains which both absorb and isotropically scatter photons. The variation with position of the extinction coefficient and dust-grain albedo is modelled by an N-state Markov process which, together with a non-local transport approximation, allows us to calculate analytical general and effective homogeneous solutions for the average radiation field in each phase as a function of depth into the slab. Numerical examples for two- and three-phase hierarchical media show the average radiation intensities inside the slab to be, in some cases, significantly enhanced by the inclusion of a third phase
Multitemporal crop surface models: accurate plant height measurement and biomass estimation with terrestrial laser scanning in paddy rice

Abstract Appropriate field management requires methods of measuring plant height with high precision, accuracy, and resolution. Studies show that terrestrial laser scanning (TLS) is suitable for capturing small objects like crops. In this contribution, the results of multitemporal TLS surveys for monitoring plant height on paddy rice fields in China are presented. Three campaigns were carried out on a field experiment and on a farmer’s conventionally managed field. The high density of measurement points allows us to establish crop surface models with a resolution of 1 cm, which can be used for deriving plant heights. For both sites, strong correlations (each R 2 = 0.91 between TLS-derived and manually measured plant heights confirm the accuracy of the scan data. A biomass regression model was established based on the correlation between plant height and biomass samples from the field experiment ( R 2 = 0.86 ). The transferability to the farmer’s field was supported with a strong correlation between simulated and measured values ( R 2 = 0.90 ). Independent biomass measurements were used for validating the temporal transferability. The study demonstrates the advantages of TLS for deriving plant height, which can be used for modeling biomass. Consequently, laser scanning methods are a promising tool for precision agriculture.
The Generalized Thin‐Film Optical Method in Electromagnetic Wave Propagation

The simple thin-film optical method is generalized to take into account intermode coupling and oblique incidence in a plane stratified magnetoionic medium. In analogy with the simple thin-film optical method, all partial reflections within a thin, elementary layer are given as a geometric series of matrix products, which are summed to yield the over-all transfer coefficient matrices of the elementary layer in terms of the characteristic waves of the medium (off-diagonal elements representing the over-all intermode coupling coefficients). The analysis is extended by an iterative procedure, layer by layer, starting high in the ionosphere and terminating at the ionospheric base to yield the over-all transmission and reflection coefficient matrices of the medium. The ‘reverse iteration,’ starting low and extending upward, yields transfer coefficient matrices of intermediate ionospheric slabs but at the price of a more complex iteration procedure. The method is free of the tendency to numerical swamping and in the case of normal incidence simplifies considerably. Applications to LF and hydromagnetic wave propagation in the lower ionosphere are given.