Miracle-dz/UniFAR-FTUs huggingface dataset:
Correcting for Seam Bias when Estimating Discrete Variable Models, with an Application to Analyzing the Employment Dynamics of Disadvantaged Women in the SIPP 1

Seam Bias occurs when respondents are asked retrospectively about economic actions and conditions, and tend to heap changes to the end of the retrospective period. It occurs, for example, in the SIPP, various data sets from the NLS, the CPS, as well as in some banking data. Pischke (1995) proposes a method for dealing with seam bias when using continuous data. Here we address the issues that occur with discrete variable models when seam bias is present. We focus specifically on estimating duration models as these are likely to be most severely affected by seam bias since the seam bias affects the timing of transitions. The extension to other discrete variable models is straight forward, as is the extension to fully structural models based explicitly on optimizing behavior. In particular we focus on the employment dynamics of single mothers with a high school degree or less using duration models. Researchers and policymakers have long been interested in this group of women, in particular because these are the women whose families are most likely to be in poverty. Estimating duration models on longitudinal data allows for time changing factors that may differentially impact entries and exits from various labor market states to be identified. However, in using such longitudinal data, researchers must confront seam bias, and we propose and implement a number of potential solutions for this problem. These include maximum likelihood estimation (MLE) of misreporting models both where the misreporting is constant across individuals and where it varies with demographic characteristics, as well as the simpler solutions of i) using only data on the month prior to the interview, and ii) using a dummy variable coded one for the seam months. We discuss identification of the MLE models, and show that they are identified without restricting the functional form of the duration dependence. We find that using only the seam month data affects the statistical significance of individual explanatory variables, but does not appear to affect the estimates of the effect of changing an explanatory variable on expected duration. Using the seam month dummy approach appears to produce estimates quite similar to those from the seam bias correction models in terms of significance and the effect of an explanatory variable on the expected duration. Finally, even though race significantly affects the misreporting probability, assuming this probability is constant across individuals does not appear to lead to biased estimates.
Modeling the Behavior of Flow Regulating Devices in Water Distribution Systems Using Constrained Nonlinear Programming

Currently the modeling of check valves and flow control valves in water distribution systems is based on heuristics intermixed with solving the set of nonlinear equations governing flow in the network. At the beginning of a simulation, the operating status of these valves is not known and must be assumed. The system is then solved. The status of the check valves and flow control valves are then changed to try to determine their correct operating status, at times leading to incorrect solutions even for simple systems. This paper proposes an entirely different approach. Content and co-content theory is used to define conditions that guarantee the existence and uniqueness of the solution. The work here focuses solely on flow control devices with a defined head discharge versus head loss relationship. A new modeling approach for water distribution systems based on subdifferential analysis that deals with the nondifferentiable flow versus head relationships is proposed in this paper. The water distribution equations are solved as a constrained nonlinear programming problem based on the content model where the Lagrangian multipliers have important physical meanings. This new method gives correct solutions by dealing appropriately with inequality and equality constraints imposed by the presence of the flow regulating devices (check valves, flow control valves, and temporarily closed isolating valves). An example network is used to illustrate the concepts.
Analysis of the numerical dispersion of the 2D alternating-direction implicit FDTD method

The numerical dispersion property of the two-dimensional alternating-direction implicit finite-difference time-domain (2D ADI FDTD) method is studied. First, we notice that the original 2D ADI FDTD method can be divided into two sub-ADI FDTD methods: either the x-directional 2D ADI FDTD method or the y-directional 2D ADI FDTD method; and secondly, the numerical dispersion relations are derived for both the ADI FDTD methods. Finally, the numerical dispersion errors caused by the two ADI FDTD methods are investigated. Numerical results indicate that the numerical dispersion error of the ADI FDTD methods depends highly on the selected time step and the shape and mesh resolution of the unit cell. It is also found that, to ensure the numerical dispersion error within certain accuracy, the maximum time steps allowed to be used in the two ADI FDTD methods are different and they can be numerically determined.
Analysis of Linear Viscoelasticity of a Crosslinking Polymer at the Gel Point

We suggest a very simple memory integral constitutive equation for the stress in crosslinking polymers at their transition from liquid to solid state (gel point). The equation allows for only a single (! ) material parameter, the strength S[Pas1/2], and it is able to describe every known viscoelastic phenomenon at the gel point. Measurements were performed on polydimethylsiloxane model networks with balanced stoichiometry for which the crosslinking reaction has been stopped at different degrees of conversion. At the gel point, the loss and storage moduli were found to be congruent and proportional to ω1/2 over a wide range of temperature (−50°C to +180°C) and five decades of frequency ω. The hypothesis is made that this behavior is valid in the entire range 0<ω<∞. This congruence hypothesis is consistent with the Kramers‐Kronig relation and leads to a constitutive equation which shows that, for our polymer, congruent functions G′(ω)=G″(ω) are as much a rheological property at the gel point as are infinite .
Contribution of Sucrose Metabolism in Phloem to Kiwifruit Bacterial Canker Resistance

Kiwifruit bacterial canker, caused by Pseudomonas syringae pv. actinidiae (Psa), is a catastrophic disease affecting kiwifruit worldwide. As no effective cure has been developed, planting Psa-resistant cultivars is the best way to avoid bacterial canker in kiwifruit cultivation. However, the differences in the mechanism of resistance between cultivars is poorly understood. In the present study, five local kiwifruit cultivars were used for Psa resistance evaluation and classified into different resistance categories, tolerant (T), susceptible (S), and highly susceptible (HS), based on their various symptoms of lesions on the cane. Susceptible and highly susceptible varieties had a higher sucrose concentration, and a greater decrease in sucrose content was observed after Psa inoculation in phloem than in tolerant varieties. Three invertase activities and their corresponding gene expressions were detected in the phloem with lesions and showed the same trends as the variations in sucrose concentration. Meanwhile, after Psa inoculation, enzyme activities involved in antioxidant defense responses, such as PAL, POD, and CAT, were also altered in the phloem of the lesion position. With no differences among cultivars, PAL and POD activities in phloem first increased and then decreased after Psa inoculation. However, great differences in CAT activities were observed between T and S/HS categories. Our results demonstrate that sucrose content was negatively correlated with the disease resistance of different cultivars and that the increase in immune response enzymes is likely caused by increased sucrose metabolism in the phloem.
Solitary kinetic Alfvén waves in the two‐fluid model

Employing the two‐fluid model, a generalized Sagdeev equation governing solitary kinetic Alfven waves (SKAWs) and the criterion for the existence of SKAWs, which are valid for different ranges of plasma pressure parameter β, are presented. In the limit cases of β≫me/mi and β≪me/mi, the present results correspond, respectively, with conclusions obtained by Hasegawa et al. [Phys. Rev. Lett. 37, 690 (1976)] and by Shukla et al. [J. Plasma Phys. 28, 125 (1982)], that is, SKAWs accompanied by, respectively, hump and dip density solitons for β≫me/mi and β≪me/mi. However, for the case of β∼me/mi, the present results show that SKAWs accompanied by both hump and dip density solitons are possible, and lead to KdV solitons in the small amplitude limit. In addition, the possibility for applying these results to electromagnetic spikes observed by the Freja scientific satellite is discussed [detailed information about the Freja satellite experiments can be found in serial papers presented in Space Sci. Rev. 70, Nos. 3/.
Pulsars in Globular Clusters

Abstract Globular clusters produce orders of magnitude more millisecond pulsars per unit mass than the Galactic disk. Since the first cluster pulsar was uncovered 20 years ago, at least 138 have been identified – most of which are binary millisecond pulsars. Because their origins involve stellar encounters, many of the systems are exotic objects that would never be observed in the Galactic disk. Examples include pulsar-main sequence binaries, extremely rapid rotators (including the current record holder), and millisecond pulsars in highly eccentric orbits. These systems are allowing new probes of the interstellar medium, the equation of state of material at supra-nuclear density, the masses of neutron stars, and globular cluster dynamics.
Prime ideal structure in commutative rings

0. Introduction. Let ' be the category of commutative rings with unit, and regard Spec (as in [1]) as a contravariant functor from ' to g$7 the category of topological spaces and continuous maps. The spaces of the form Spec A, A a ring (ring always means object of '), are well known to have many special properties. It is worthwhile to discover whether these well-known properties of the spaces characterize them, since we then will know the limitations of the topological approach. As a by-product of this study, remarkable facts about the structure of the prime ideals in a commutative ring come to light. E.g. given any ring A there is a ring whose prime ideals have precisely the reverse order of the primes of A. In the same vein, on the topological level there is a complete duality between localization and taking residue class rings (see ? 8, Proposition 8). We call a space spectral if it is To and quasi-compact, the quasi-compact open subsets are closed under finite intersection and form an open basis, and every nonempty irreducible closed subset has a generic point. Spec A, A a ring, is well known to be spectral, and in fact these properties do characterize the spaces in the image of Spec. However, there are much more enlightening characterizations. For example, the last property on the list is a very special case of a much more general property of spectral spaces-best described as the compactness of a new topology on the spectral space which is derived from the original topology. Again, the spectral spaces are precisely the projective limits of finite To spaces. Proving that these properties characterize the image of Spec involves constructing a large number of rings. This construction (? 3-7) is very intricate, but is practically choice-frep and turns out to be fairly functorial. Moreover, we can fix any field k and get the constructed rings to be k-algebras. To be more precise about the functorial aspects, we define a continuous map of spectral spaces to be spectral if inverse images of quasi-compact open sets are quasi-compact. Let Y be the subcategory of $-consisting of spectral spaces and spectral maps. Then it is well known that every space and map in the image of Spec is in Y and it will turn out that up to isomorphism, every space and map in Y is in the image of Spec. In this sense, we may say that Y is precisely the image of Spec. We say that Spec is invertible on a subcategory I of Y if there is a (contravariant) functor F: q -W' whose composition with Spec is isomorphic with the inclusion
Crop production in Türkiye: trends and driving variables

Climate change and a rapidly increasing population boost the pressure on Türkiye’s cropping systems to increase crop production in order to meet rising food demand. It is unknown whether and in which direction trends and variability in harvested area and yield separately affect crop production in Türkiye. The objective of this study was to (1) quantify the long-term (2004–2020) trends of planting/harvested areas, yield and crop production for the 16 vital annual crops in Türkiye, (2) quantify the separate contribution of harvested area and yield on crop-specific production variability and (3) the potential of water and temperature-based remote sensing variables on capturing the variability of harvested areas and yield. The harvested area of the most grown crops (10 out of 16) such as wheat and barley showed a declining trend. However, the yield trend was increased for all of the study crops, which in some cases overcompensated for the decline in the harvested area on crop production. The harvested area showed a more robust explanatory power for production variability than yield except for the crops with higher breeding investments and subsidized by authorities such as wheat and sugar beet. The water-related remote sensing variables and combination of water and temperature variables largely explained the variability of the harvested area in Türkiye. In order to stabilize crop production in Türkiye, better and more efficient water management plans are crucial.
Effective theory of bosonic superfluids

We discuss the effective theory of a bosonic superfluid whose microscopic behavior is described by a nonrelativistic, weak-coupling Φ4 theory in the phase with broken particle number symmetry, both at zero temperature and in the vicinity of the phase transition. In the zero-temperature regime, the theory is governed by the gapless Goldstone mode resulting from the broken . symmetry. Although this mode is gapless, the effective theory turns out to be Gallilei invariant. The regime just below the critical temperature is approached in a high-temperature expansion which is shown to be consistent with the weak-coupling assumption of the theory. We calculate the critical temperature, the co-efficients of the Landau theory, and the finite-temperature sound velocity. A comparison with BCS theory is given.
A simple proof of a no-hair theorem in Einstein-Higgs theory

We give a new simple proof of the fact that there are no non-trivial black holes with a regular horizon in Einstein-Higgs theory with any number of scalar fields and an arbitrary potential. We also give a brief discussion on the contrast between this theory and the Einstein-Yang-Mills theory that is responsible for the difference in the set of solutions allowed by each one.
Donation type and the effect of pre-transplant donor specific antibodies – Data from the Swiss Transplant Cohort Study

Introduction The type of donation may affect how susceptible a donor kidney is to injury from pre-existing alloimmunity. Many centers are, therefore, reluctant to perform donor specific antibody (DSA) positive transplantations in the setting of donation after circulatory death (DCD). There are, however, no large studies comparing the impact of pre-transplant DSA stratified on donation type in a cohort with a complete virtual cross-match and long-term follow-up of transplant outcome. Methods We investigated the effect of pre-transplant DSA on the risk of rejection, graft loss, and the rate of eGFR decline in 1282 donation after brain death (DBD) transplants and compared it to 130 (DCD) and 803 living donor (LD) transplants. Results There was a significant worse outcome associated with pre-transplant DSA in all of the studied donation types. DSA directed against Class II HLA antigens as well as a high cumulative mean fluorescent intensity (MFI) of the detected DSA showed the strongest association with worse transplant outcome. We could not detect a significant additive negative effect of DSA in DCD transplantations in our cohort. Conversely, DSA positive DCD transplants appeared to have a slightly better outcome, possibly in part due to the lower mean fluorescent intensity (MFI) of the pre-transplant DSA. Indeed when DCD transplants were compared to DBD transplants with similar MFI (<6.5k), graft survival was not significantly different. Discussion Our results suggest that the negative impact of pre-transplant DSA on graft outcome could be similar between all donation types. This suggests that immunological risk assessment could be performed in a similar way regardless of the type of donor kidney transplantation.
Bayesian Minimally Supported D-Optimal Designs for an Exponential Regression Model

Abstract We consider the problem of obtaining static (i.e., nonsequential), approximate optimal designs for a nonlinear regression model with response E[Y|x] = exp(θ0 + θ1 x + · + θ k x k ). The problem can be transformed to the design problem for a heteroscedastic polynomial regression model, where the variance function is of an exponential form with unknown parameters. Under the assumption that sufficient prior information about these parameters is available, minimally supported Bayesian D-optimal designs are obtained. A general procedure for constructing such designs is provided; as well the analytic forms of these designs are derived for some special priors. The theory of canonical moments and the theory of continued fractions are applied for these purposes.
Clear Aligners Treatment of Class III Subdivision with an Extraction of a Lower Bicuspid

The aim of this study was to show a case of a Class III subdivision adult patient treated with clear aligners (CA) and the extraction of a lower bicuspid. A 19-year-old male with a class III canine and molar relationship on the right side and a deviation of lower dental midline to the left asked for an aesthetic treatment. He refused orthognathic surgical procedures, so he was offered a camouflage orthodontic treatment with the extraction of lower right first premolar to achieve a canine Class I relationship and to center the lower midline. The treatment was performed with clear aligners and the use of Class III elastics to maintain distal anchorage on the right side during the canine distalization. At the end of the treatment, the occlusal objectives were achieved.
Synthesis of multireflector antennas by kinematic and dynamic ray tracing

A technique for synthesizing reflector surfaces that transform a known input ray-field (e.g., the radiation field of a feed) to a desired output ray-field (e.g. an aperture distribution) is presented. The synthesis problem is reduced to solving linear equations by local biparabolic expansions of the reflector surfaces. Because the solution is easier to control, this is advantageous compared to existing techniques based on solving nonlinear differential equations. The condition to obtain low cross polarization can therefore be readily included, and the requirements for an exact solution to exist can be found clearly. The latter has been the subject of discussion in the literature for several years. The synthesis technique is applied to a shaped-offset dual-reflector antenna and to the proposed dual-reflector feed of the spherical reflector antenna in Arecibo. In both cases circular and elliptical apertures are considered. >
Non-parametric identification with errors in independent variables

The problem of non-parametric identification of a static system is considered in the presence of errors both in dependent and independent variables. Identification is based on the orthogonal series expansion. Errors in independent variables are modelled in two ways, namely as pointwise errors and as errors caused by an averaging. Sufficient conditions for MISE consistency are proved in both cases.
Kimura disease in children: A report of 11 cases and review of the literature

Introduction Kimura disease (KD), also known as eosinophilic hyperplastic lymphoid granuloma, is a rare benign chronic inflammatory condition, which is featured with the painless progressive mass located in the subcutaneous area of the head and neck region, elevated peripheral blood eosinophils, and raised serum immunoglobulin E (IgE) levels. KD is uncommon in clinical practice, especially with low incidence in children, so it often leads to misdiagnosis or missed diagnosis in pediatric patients. Methods The clinical data of 11 pediatric patients with KD in the authors' institution were retrospectively analyzed. Results There were 11 pediatric patients with KD enrolled in total, including 9 male patients and 2 female patients (sex ratio 4.5:1). The median age at diagnosis stood at 14 years (range 5-18 years), the initial symptoms in all patients included painless subcutaneous masses and focal swelling, the duration of symptoms ranged from 1 month to 10 years, and the average duration was 24.45 months. Six patients had single lesions, and 5 had multiple lesions. The highest proportion of lesion regions were parotid gland (n = 5, 31.3%) and retroauricular (n = 5, 31.3%), followed by cervical lymph nodes (n = 4, 25%), and others (n = 2,12.5; elbow n = 1; back n = 1). The eosinophil absolute count elevated in all patients, ranging from 0.71×109/L to 10.35 ×109/L (normal range 0.02-0.52×109/L). IgE levels were increased in all 7 patients who underwent serum immunoglobulin examination (normal range <100 IU/mL). Three patients received oral corticosteroid treatment while 2 relapsed. Three patients received surgical resection combined with oral corticosteroid treatment, and no patient relapsed. The other 3 patients received surgery and radiotherapy, surgery combined with corticosteroid and cyclosporin and corticosteroid combined with leflunomide respectively, and no patient relapsed. Conclusion Base on the study, it is found that Kimura disease is rare and may have the atypical symptoms in pediatric patients, combination therapy is recommended to reduce recurrence, and long-term follow-up should be performed.
Linear Quadratic Optimal Stochastic Control with Random Coefficients

The purpose of this paper is to apply the methods developed in [1] and [2] to solve the problem of optimal stochastic control for a linear quadratic system.After proving some preliminary existence results on stochastic differential equations, we show the existence of an optimal control.The introduction of an ad joint variable enables us to derive extremality conditions: the control is thus obtained in random “feedback” form. By using a method close to the one used by Lions in [4] for the control of partial differential equations, a priori majorations are obtained.A formal Riccati equation is then written down, and the existence of its solution is proved under rather general assumptions.For a more detailed treatment of some examples, the reader is referred to [1].
On output regulation for linear systems

We revisit the output regulation problem for linear systems. We generalize the problem formulation in order to expand the class of tracking reference or disturbance rejecting signals, to utilize the derivative or feedforward information of reference signals whenever it is available, and to pursue alternative avenues of design whenever the exact output regulation problem is not solvable.