Miracle-dz/UniFAR-FTUs huggingface dataset:
ARMA MODELS WITH ARCH ERRORS

This paper considers the class of ARMA models with ARCH errors. Maximum Likelihood and Least Squares estimates of the parameters of the model and their covariance matrices are noted and incorporated into techniques for model building based upon the application of the usual Box‐Jenkins methodology of identification, estimation and diagnostic checking to the ARMA equation, the ARCH equation, and the full model. The techniques are applied to 16 U.S. macroeconomic time series and it is seen that in many of the series, models from this class can be constructed.
Application of laser-based resonant ultrasound spectroscopy to study texture in copper

Two copper specimens with distinct grain microstructures are investigated using laser resonant ultrasound spectroscopy (LRUS). One consists of randomly oriented crystallites and exhibits isotropic elastic behavior (two elastic constants), and the other has been highly textured by rolling and exhibits anisotropic elastic behavior (three elastic constants). The elastic constants are measured using electron backscatter diffraction, LRUS, and time domain laser ultrasound (LU). The elastic constants of the isotropic sample obtained via electron backscatter diffraction (EBSD), LU, and LRUS agree closely. However, for the anisotropic sample, there is considerable disagreement between results obtained using LRUS and results obtained using LU and EBSD. Analysis reveals that increasing the dimensionality of the modulus space leads to a questions of whether the LRUS results are unique to within experimental error. The consequence is that for anisotropic materials, small measurement uncertainties can lead to large un.
DNA supercoiling modeling of nucleosome and viral spooling

New kinematic equations are used to model DNA supercoiling. These equations govern the simultaneous production of multiple folding and coiling of a filament in space by diffeomorphism of a reference curve. Here we show how to use these equations to model regions of highly localized filament coiling, where mechanisms of proteic coding or viral spooling are important. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sensitivity of Global Ensemble Forecasts to the Initial Ensemble Mean and Perturbations: Comparison of EnKF, Singular Vector, and 4D-Var Approaches

Abstract This study examines the sensitivity of global ensemble forecasts to the use of different approaches for specifying both the initial ensemble mean and perturbations. The current operational ensemble prediction system of the Meteorological Service of Canada uses the ensemble Kalman filter (EnKF) to define both the ensemble mean and perturbations. To evaluate the impact of different approaches for obtaining the initial ensemble perturbations, the operational EnKF approach is compared with using either no initial perturbations or perturbations obtained using singular vectors (SVs). The SVs are computed using the (dry) total-energy norm with a 48-h optimization time interval. Random linear combinations of 60 SVs are computed for each of three regions. Next, the impact of replacing the initial ensemble mean, currently the EnKF ensemble mean analysis, with the higher-resolution operational four-dimensional variational data assimilation (4D-Var) analysis is evaluated. For this comparison, perturbations a.
Field-induced staggered magnetization near impurities in the S= one-dimensional Heisenberg antiferromagnet Sr 2 CuO 3

We report an impurity effect in the spin- one-dimensional Heisenberg antiferromagnet ${\mathrm{Sr}}_{2}$${\mathrm{CuO}}_{3}$. The $^{63}\mathrm{Cu}$ NMR spectra develop a broad background with sharp edges at low temperatures. The anisotropy and the temperature dependence of this structure indicate that the external magnetic field induces local staggered magnetization near impurities, whose spatial extent grows with decreasing temperature. The results are in good agreement with the theoretical prediction by Eggert and Affleck for a semi-infinite spin chain with an open end.
The Push-Door for Measuring Motivation in Hens: Laying Hens are Motivated to Perch at Night

Free-living hens perch on branches in trees and domestic hens (Gallus gallus domesticus) show signs of unrest if they cannot reach a perch, suggesting that night-time perching is a behaviour that hens are motivated to perform. This motivation was quantified in two experiments using a weighted push-door that hens had to push open in order to gain access to a perch. First, the motivation of individual birds to perch, and second, the effect of a companion bird on perching motivation, were measured. Eight adult laying hens (Lohmann Selected Leghorn) were trained to push through the door at increasing resistances, and the individual capacity of each hen was determined. Hens were then tested once per day, at lights-off in a test pen where pushing through the push-door gave access to the resource. Two consecutive series of increasing resistances were used in the experiment: 25, 50, 75 and 100 per cent of each bird's maximum capacity. In the first experiment, the resources offered were either a perch (treatment) or a ‘sham perch’ that could not be used for perching (control). Hens opened significantly heavier doors in order to gain access to a perch than to gain access to the sham perch. In the second experiment, pushing through the door gave access either to a perch with a companion hen already perching on it (treatment) or to a perch and a companion hen roosting on the floor (control). In this comparison, four of the hens did not push through the door, probably because of aggressive interactions with the companion, and no significant differences between treatments were found. We conclude that hens are motivated to use a perch for night-time roosting and that they should be housed in systems with perches.
Lateral growth kinetics of α-alumina accompanying the formation of a protective scale on (111) NiAl during oxidation at 1100 °C

During the early stages of oxidation of (111) NiAl at 1100 °C, an alumina scale forms and undergoes a series of allotropic phase transformations. In the final stages of phase development, the metastable Θ-alumina transforms to the equilibrium α-alumina phase. Images formed using the photoluminescence from trace Cr3+ impurities in the scale, in conjunction with scanning electron microscopy, indicate that the α-alumina forms by a nucleation and growth process within the Θ-alumina matrix. Lateral impingement of the growing α-alumina islands coincides with the reported drop in oxidation kinetics to those characteristic of long-term oxidation of NiAl. Unlike most interface-controlled transformations, the kinetics of the θ–to–α transformation in the lateral growth are found to be logarithmic. Possible causes of these unusual kinetics are proposed.
Genetic Selection for Poultry Behaviour: Big Bad Wolf or Friend in Need?

Although genetic selection for certain characteristics has compromised the well-being of domestic animals, selective breeding could and probably should be used to improve welfare. Three of the major behavioural problems facing the poultry industry are fear, feather pecking and social stress. However, these and many other behavioural traits respond readily to genetic selection. The present paper reports the results of selective breeding studies in which underlying fearfulness, sociality, feather pecking, adrenocortical responsiveness, and growth rate were manipulated in Japanese quail, Coturnix japonica, or in chickens, Gallus gallus domesticus. The apparent benefits of selection for appropriate levels of these characteristics are discussed, as are the ethical issues involved. The ultimate aims of the selection programmes and the studies described here are to improve the birds ‘ welfare and productivity by increasing their ability to interact successfully with their physical environment, with one another, and with human beings.
Anisotropic ferroelectric properties of anisotropically strained epitaxial NaNbO3 films

Epitaxial c-axis oriented NaNbO3 films are grown on (110) oriented NdGaO3 substrates. Due to the incorporated lattice strain the films show relaxor ferroelectric properties and an in-plane permittivity that is strongly enhanced with respect to unstrained NaNbO3. Moreover, the lattice mismatch between substrate and film leads to an anisotropy in the compressive in-plain strain of −0.67% and −1.33% for the a- and b-direction of the films, respectively. As a consequence, the ferroelectric properties of the film depend strongly on the orientation of the applied electric field. The small anisotropy of the compressive in-plane strain leads to a large anisotropy of the permittivity, a shift of the peak in the temperature dependence of the permittivity, and different freezing temperatures and activation energies Ea of the relaxor ferroelectric film.
Use of calculated sound fields and matched‐field detection to locate sound sources in shallow water

The calculated complex sound field cj for sensor j at depth zj and range rj from a sound source of frequency ω and depth z0 can be written in the normal‐mode form as cj= (2π/rj)1/2 ΣmUm(z0) Um(zj) exp[i (kmrj−ωt)]. Here, km is the horizontal wavenumber of mode m and Um is the depth function of the mth mode. It is proposed that the detection factor DF=ΣJj=1 cjc*k〈 (c0jc0k*) *〉 is a reasonable measure for determination of whether a set of sound pressure measurements {c0j} for j=1,2,⋅⋅⋅,J is a good fit to calculated values of {cj} for an assumed location of the sound source. Here 〈 〉 denotes a time average and * denotes complex conjugate. Several examples are shown where a set of {c0j} are calculated for a given source location in a typical shallow water channel and values of DF are then calculated for a grid of range depth or range azimuth locations.Subject Classification: [43]60.20; [43]30.82.
A probabilistic seismic risk analysis of building losses in Taipei: An application of Haz‐Taiwan with its pre‐processor and post‐processor

Abstract We employ a probabilistic seismic risk analysis to estimate exceedance probability curves, average annual loss (AAL) and probable maximum loss (PML) of building stocks in Taipei. It utilizes an event‐driven loss estimation model, HAZ‐Taiwan, and develops its pre‐processing and post‐processing software modules. The pre‐processing module establishes a set of hazard‐consistent scenario earthquakes. The HAZ‐Taiwan model estimates hazards, vulnerabilities and economic losses for each scenario earthquake. The aggregate and occurrence exceedance probability curves for building losses and their confidence intervals are simulated using the Monte Carlo simulation in the postprocessing module. It is found that the exceedance probability of an aggregate loss of USD 1.22 billion is 0.001. This amount of loss is approximately 2.78% of the total building stocks in Taipei. Its 5%‐95% confidence intervals range from USD 1.13–1.31 billion. The average annual loss of buildings in Taipei is currently USD 32 million, or approximately 0.07% of the total building stocks.
Evaluation of floral volatile patterns in the genus Narcissus using gas chromatography–coupled ion mobility spectrometry

Abstract Premise Daffodils (Narcissus, Amaryllidaceae) are iconic ornamentals with a complex floral biology and many fragrant species; however, little is known about floral plant volatile organic compounds (pVOCs) across the genus and additional sampling is desirable. The present study investigates whether the floral scent of 20 species of Narcissus can be characterized using gas chromatography–coupled ion mobility spectrometry (GC–IMS), with the aim of building a comparative pVOC data set for ecological and evolutionary studies. Methods We used a commercial GC–IMS equipped with an integrated in‐line enrichment system for a fast, sensitive, and automated pVOC analysis. This facilitates qualitative and (semi)‐quantitative measurements without sample preparation. Results The GC–IMS provided detailed data on floral pVOCs in Narcissus with very short sampling times and without floral enclosure. A wide range of compounds was recorded and partially identified. The retrieved pVOC patterns showed a good agreement with published data, and five “chemotypes” were characterized as characteristic combinations of floral volatiles. Discussion The GC–IMS setup can be applied to rapidly generate large amounts of pVOC data with high sensitivity and selectivity. The preliminary data on Narcissus obtained here indicate both considerable pVOC variability and a good correspondence of the pVOC patterns with infrageneric classification, supporting the hypothesis that floral scent could represent a considerable phylogenetic signal.
Can't stop, won't stop: is stereotypy a reliable animal welfare indicator?

We estimate that stereotypies are currently displayed by over 85 million farm, laboratory and zoo animals worldwide. This paper investigates their reliability as welfare indicators, by surveying studies relating stereotypy to other welfare measures and by analysing the mechanisms underlying this behaviour. Where data exist, most (approximately 68%) situations that cause/increase stereotypies also decrease welfare. Stereotypy-eliciting situations are thus likely to be poor for welfare, although exceptions exist. Within such an environment, however, most (approximately 60%) accounts link individual stereotypy performance with improved welfare (cf approximately 20% linking it with reduced welfare). Thus, in a sub-optimal environment, non-stereotyping or low-stereotyping individuals could well have the poorest welfare, although again exceptions exist. Examining the mechanisms underlying stereotypy performance, we discuss four processes that could account for these complex links between stereotypy and welfare. Beneficial consequences from performing the specific source-behaviour of the stereotypy (‘do-it-yourself enrichment’), or arising from repetition per se (‘mantra effects’), may ameliorate welfare in poor environments. In addition, stereotypies that have become centrally controlled (habit-like), or that arise from autistic-like changes in the control of all behaviour (perseveration), are likely to be unreliable indicators of current state because they can be elicited by, or persist in, circumstances that improve welfare. To refine the role of stereotypy in welfare assessment, we suggest the collection of specific additional data to reveal when any of these four processes is acting. Until such research increases our understanding, stereotypies should always be taken seriously as a warning sign of potential suffering, but never used as the sole index of welfare; non-stereotyping or low-stereotyping individuals should not be overlooked or assumed to be faring well; simple measures of frequency should not be used to compare stereotypies that differ in age, form, or the biological or experiential characteristics of the performing animal; enrichments that do not immediately reduce stereotypies should not be assumed failures with respect to welfare; and finally, stereotypies should not be reduced by means other than tackling their underlying motivations.
Optimal control of deterministic epidemics

Various deterministic optimal control models for SIR‐epidemics are investigated in this paper. The epidemics are governed by a rather general interaction, which covers most cases studied in the literature. Vaccination, quarantine, screening or health promotion campaigns as forms of control are considered. In all cases one finds a maximum effort control on some initial time interval. In addition, uniqueness and monotonicity properties of these models are studied. The results are also extended to the infinite time‐horizon situation. Copyright © 2000 John Wiley & Sons, Ltd.
What causes crowding? Effects of space, facilities and group size on behaviour, with particular reference to furnished cages for hens

Theoretical models are presented of the effects of space, facilities and group size on the behaviour of chickens at high stocking densities, with relevance for all animals. The appropriateness of each model is supported by published data, although such data are scant for some important variables. Freedom of movement is analysed by taking the area of a hen as 475 cm2 and finding the number of free bird spaces left at different space allowances. This provides support for current recommendations of a maximum of seven laying hens per m2 on deep litter, but suggests that a maximum for broilers of 34 kg/m2 unacceptably restricts freedom of movement. In cages, freedom of movement increases with space allowance per hen, and, for a given space allowance, with cage and group size. Nesting behaviour is analysed for synchrony, which decreases with group size. Perching and feeding are often synchronous and the space needed for these is determined by body width. Recommendations are derived for hens in furnished cages. The main part of the cage should be as large as possible; an absolute minimum of 600 cm2 per bird is suggested, but 675 cm2 per bird is probably the minimum practical. Perch and feeder space should be provided at 14 cm or more per bird, with a possible derogation for light hybrids to 12 cm. The number of nest spaces needed varies with the number of birds, with nest spaces being 300 cm2 each. These recommendations sum to a minimum of 800 cm2 per bird for groups of eight or more, 850 cm2 for groups of four to seven, and 900 cm2 for groups of three or fewer, plus litter area. Crowding is primarily caused by limited space allowance, but for a given space allowance it is worse in small enclosures and groups.
Mental health impact of autism on families of children with intellectual and developmental disabilities of genetic origin

Abstract Background Many children with an intellectual or developmental disability (IDD) have associated autism spectrum disorders (ASD), as well as an increased risk of mental health difficulties. In a cohort with IDD of genetic aetiology, we tested the hypothesis that excess risk attached to those with ASD + IDD, in terms of both children's mental health and parental psychological distress. Methods Participants with a copy number variant or single nucleotide variant (5–19 years) were recruited via UK National Health Service. 1904 caregivers competed an online assessment of child mental health and reported on their own psychological wellbeing. We used regression to examine the association between IDD with and without co‐occurring ASD, and co‐occurring mental health difficulties, as well as with parental psychological distress. We adjusted for children's sex, developmental level, physical health, and socio‐economic deprivation. Results Of the 1904 participants with IDD, 701 (36.8%) had co‐occurring ASD. Children with both IDD and ASD were at higher risk of associated disorders than those with IDD alone (ADHD: OR = 1.84, 95% confidence interval [CI] 1.46–2.32, p < 0.0001; emotional disorders: OR = 1.85, 95%CI 1.36–2.5, p < 0.0001; disruptive behaviour disorders: OR = 1.79, 95%CI 1.36–2.37, p < 0.0001). The severity of associated symptoms was also greater in those with ASD (hyperactivity: B = 0.25, 95%CI 0.07–0.34, p = 0.006; emotional difficulties: B = 0.91, 95%CI 0.67 to 1.14, p < 0.0001; conduct problems: B = 0.25, 95%CI 0.05 to 0.46, p = 0.013). Parents of children with IDD and ASD also reported greater psychological distress than those with IDD alone (β = 0.1, 95% CI 0.85 to 2.21, p < 0.0001). Specifically, in those with ASD, symptoms of hyperactivity (β = 0.13, 95% CI 0.29–0.63, p < 0.0001), emotional difficulties (β = 0.15, 95% CI 0.26–0.51, p < 0.0001) and conduct difficulties (β = 0.07, 95% CI 0.07–0.37, p < 0.004) all significantly contributed to parental psychological distress. Conclusions Among children with IDD of genetic aetiology, one third have co‐occurring ASD. Not only do those with co‐occurring ASD present with a wider range of associated mental health disorders and more severe mental health difficulties than those with IDD alone, but their parents also experience more psychological distress. Our findings suggest that the additional mental health and behavioural symptoms in those with ASD contributed to the degree of parental psychological distress.
Identifying and Screening At-Risk Patients for Hepatitis Delta Virus: A Case Report

Hepatitis Delta Virus (HDV) is associated with one of the most severe forms of viral hepatitis, with rapid progression to cirrhosis and hepatocellular carcinoma. While HDV was thought to be uncommon in the United States, recent data shows that its prevalence may be significantly higher than formerly acknowledged. Early identification of HDV is critical since approved therapeutic options are only available for compensated patients. All patients with a reactive hepatitis B virus surface antigen should undergo HDV screening, especially those with additional risk factors, including migration from an endemic area, immunosuppressed patients, hemodialysis patients, gay and bisexual men, persons who inject drugs, and persons employed in healthcare or public safety professions.
On global and pointwise adaptive estimation

Let an estimated function belong to a Lipschitz class of order a. Consider a minimax approach where the infimum is taken over all possible estimators and the supremum is taken over the considered class of estimated functions. It is known that, if the order a is unknown, then the minimax mean squared (pointwise) error convergence slows down from n-2a/(2a+1) for the case of the given a to [n/In (n)]-2a/(2a+l). At the same time, the minimax mean integrated squared (global) error convergence is proportional to n-2a/(2a+l) for the cases of known and unknown a. We show that a similar phenomenon holds for analytic functions where the lack of knowledge of the maximal set to which the function can be analytically continued leads to the loss of a sharp constant. Surprisingly, for the more general adaptive minimax setting where we consider the union of a range of Lipschitz and a range of analytic functions neither pointwise error convergence nor global error convergence suffers an additional slowing down.