Dimensional Factor Research Articles

Dimensional latent factor structure of psychopathology in adults with chronic illness.

The goal of the present study was to determine if the internalizing and externalizing model of psychopathology is applicable in a sample of adults with chronic illness. Confirmatory factor analyses were used to examine the factor structure of internalizing and externalizing symptoms in a sample of adults (N = 172) with a unique chronic physical health condition (postural orthostatic tachycardia syndrome; POTS) and in a sample of adults without any chronic illness diagnoses (N = 199). Measurement invariance was used to compare levels of internalizing and externalizing symptoms across samples. Confirmatory factor analyses suggested that psychological distress in individuals with chronic illness can be effectively characterized by an internalizing dimension composed of distress and fear subcomponents as well as an externalizing dimension. Measurement invariance testing reached adequate levels of fit, allowing for examination of latent means; individuals with chronic illness had higher scores on the internalizing dimension and lower scores on the externalizing dimension than healthy controls. Regression analyses suggested that among those with a chronic illness, internalizing symptoms were significantly, negatively related to acceptance of illness and higher health-related quality of life. Findings suggest that assessing internalizing symptoms broadly may allow for better identification of chronically ill individuals experiencing psychological distress than a focus on categorical diagnoses. However, professionals also need to be aware of the overlap between physical and psychological symptoms in adults with chronic illnesses in order to avoid inaccurate diagnoses. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

A 3-D-Printed Wideband Circularly Polarized Dielectric Reflectarray of Cross-Shaped Element

A novel wideband circularly polarized (CP) dielectric reflectarray operating at Ka -band is proposed. Each element consists of a cross-shaped dielectric block and a metal ground. The two arms of the cross element are arranged along the diagonal of the square metal floor. For ease of the design, the dimensional scaling factor is used to obtain the reflection phase. The dielectric reflectarray of the size 15 × 15 and dielectric constant 9.8 is designed. Genetic algorithm (GA) is applied to optimize the element size. It is found that the maximum gain is 24.2 dBi, and 1 dB gain bandwidth is 10.7%, respectively. A broad 3 dB axial ratio (AR) bandwidth of 19.3% can also be obtained. The proposed CP antenna is fabricated using the high-precision 3-D printing technology. Relatively good agreement between the simulated and measured results is achieved.

Structural Brain Patterns Associated with Traumatic Stress Resilience and Susceptibility to Mood and Anxiety Symptoms in Youths

Understanding biological mechanisms underlying traumatic stress resilience is critical and can advance preventive psychiatry. Brain phenotypes of stress resilience have been investigated in animals, but such data in humans is scarce. Here we characterize cross-sectional brain correlates of traumatic stress resilience and susceptibility to mood and anxiety psychopathology (MAP) in community youth with substantial trauma exposure. Philadelphia Neurodevelopmental Cohort youths with high-quality structural neuroimaging data were included (N = 1392, mean age ~ 15). MAP was quantified using a dimensional factor score. Resilience and susceptibility were ascertained retrospectively and defined as low/high MAP (respectively) in relation to trauma exposure. This resilience-susceptibility construct was operationalized as the interaction term between trauma exposure and MAP. Clinical functioning level was quantified with the Children Global Assessment Scale. Statistical models examined association of volume, cortical thickness, and gray matter density with resilience, covarying for age, sex, race, socioeconomic status, and image quality. Resilience was associated with better clinical functioning and with specific neural correlates, such that in extensive traumatic stress exposure, smaller brain volume was associated with low MAP; while in low trauma exposure, smaller volumes were correlated with higher MAP. This pattern was evident in total brain volume (trauma by MAP interaction, F(1, 1383), p < .05), and in volumes of white matter, parietal lobe, basal ganglia, and within basal ganglia (nucleus accumbens, globus pallidus, and putamen) (all FDR corrected p’s < .05). Exploratory analyses revealed no such interaction in the hippocampus or amygdala. Findings suggest that in substantial childhood/adolescent life trauma exposure, larger brain volume, usually considered protective, is inversely associated with resilience.

Estimating and testing high dimensional factor models with multiple structural changes

This paper considers multiple changes in the factor loadings of a high dimensional factor model occurring at dates that are unknown but common to all subjects. Since the factors are unobservable, the problem is converted to estimating and testing structural changes in the second moments of the pseudo factors. We consider both joint and sequential estimation of the change points and show that the distance between the estimated and the true change points is Op(1). We find that the estimation error contained in the estimated pseudo factors has no effect on the asymptotic properties of the estimated change points as the cross-sectional dimension N and the time dimension T go to infinity jointly. No N-T ratio condition is needed. We also propose (i) tests for no change versus l changes (ii) tests for l changes versus l+1 changes, and show that using estimated factors asymptotically has no effect on their limit distributions if T∕N→0. These tests allow us to make inference on the presence and number of structural changes. Simulation results show good performance of the proposed procedure. In an application to US quarterly macroeconomic data we detect two possible breaks.

Theoretical and practical recommendations on selection of municipal solid waste landfill sites with the subsequent reclamation of disturbed lands in the Konstantinovskiy District, Amur Region

The study in hand confirms that the basic strategy of MSW management is landfilling, not recycling. Drawing from the results of the dimensional multiple factor analysis of region-specific characteristics, the authors provide recommendations on selecting MSW landfill sites and their subsequent reclamation for the Konstantinovskiy District, Amur Region.

Variational inference for high dimensional structured factor copulas

Factor copula models have been recently proposed for describing the joint distribution of a large number of variables in terms of a few common latent factors. A Bayesian procedure is employed in order to make fast inferences for multi-factor and structured factor copulas. To deal with the high dimensional structure, a Variational Inference (VI) algorithm is applied to estimate different specifications of factor copula models. Compared to the Markov Chain Monte Carlo (MCMC) approach, the variational approximation is much faster and could handle a sizeable problem in limited time. Another issue of factor copula models is that the bivariate copula functions connecting the variables are unknown in high dimensions. An automatic procedure is derived to recover the hidden dependence structure. By taking advantage of the posterior modes of the latent variables, the bivariate copula functions are selected by minimizing the Bayesian Information Criterion (BIC). Simulation studies in different contexts show that the procedure of bivariate copula selection could be very accurate in comparison to the true generated copula model. The proposed procedure is illustrated with two high dimensional real data sets.

The hybrid dimensional representation of permeability tensor: A reinterpretation of the discrete fracture model and its extension on nonconforming meshes

The discrete fracture model (DFM) has been widely used in the simulation of fluid flow in fractured porous media. Traditional DFM uses the so-called hybrid-dimensional approach to treat fractures explicitly as low-dimensional entries (e.g. line entries in 2D media and face entries in 3D media) on the interfaces of matrix cells and then couple the matrix and fracture flow systems together based on the principle of superposition with the fracture thickness used as the dimensional homogeneity factor. Because of this methodology, DFM is considered to be limited on conforming meshes and thus may raise difficulties in generating high quality unstructured meshes due to the complexity of fracture's geometrical morphology. In this paper, we clarify that the DFM actually can be extended to non-conforming meshes without any essential changes. To show it clearly, we provide another perspective for DFM based on hybrid-dimensional representation of permeability tensor to describe fractures as one-dimensional line Dirac delta functions contained in permeability tensor. A finite element DFM scheme for single-phase flow on non-conforming meshes is then derived by applying Galerkin finite element method to it. Analytical analysis and numerical experiments show that our DFM automatically degenerates to the classical finite element DFM when the mesh is conforming with fractures. Moreover, the accuracy and efficiency of the model on non-conforming meshes are demonstrated by testing several benchmark problems. This model is also applicable to curved fracture with variable thickness.

Dimensionality determination: A thresholding double ridge ratio approach

Underdetermination of model dimensionality (order) is a longstanding problem when existing eigendecomposition-based criteria are used. To alleviate this difficulty, we propose a thresholding double ridge ratio criterion in this paper. Unlike all existing eigendecomposition-based criteria, the proposed criterion can provide a consistent estimate even when there are several local minima. For illustration, we present the generic strategy with three important applications: dimension reduction in regressions with fixed and divergent dimensions; model checking with local alternative models; and ultra-high dimensional approximate factor models. Numerical studies are conducted to examine the finite sample performance of the proposed method and a real data example is analyzed for illustration.

Analytic approach to study a hybrid plasmonic waveguide-fed and numerically design a nano-antenna based on the new director.

In this paper, a wideband InP-based hybrid plasmonic nano-antenna (HPNA) operating at telecommunication wavelengths has been proposed. Monolithically integrating InP-based lasers with hybrid plasmonic waveguide (HPW) as a feed line of the proposed HPNA on the same InGaAsP/InP wafer can increase the antenna efficiency. A new vertical director has been employed to have a highly directive horizontal radiation pattern. This enhancement is attributed to the efficient coupling between the radiation patterns of arm elements as well as reduced side lobes and back-lobes levels due to the achieved impedance matching. As a result, the directivity has been increased considerably, 3.6 dBi at 193.5 THz (1550 nm) and 1.1 dBi at 229 THz (1310 nm). The HPNA shows the high directivity, total efficiency and quality factor of 11.8, 97.49% and 94.57, respectively. Further, to verify the validity of confining the fundamental TM mode to a thin layer with the lower refractive index, both theoretical and numerical methods have been employed. Therefore, we have derived an analytical formula to investigate the HPW dispersion relation based on the transfer matrix theory and genetic algorithm. Moreover, due to the HPNA ability to receive an optical signal from free space and transmit it to the waveguide based on the reciprocity theorem, the HPNA performance as an optical wireless on-chip nano-link has been investigated analytically and numerically. Additionally, to obtain a high optical power signal and steering the beam angle, the antenna gain and directivity have been calculated with two different types of array structure by controlling the relative phase shift between the array elements and elements number. To validate the array design performance, a three dimensional full-wave numerical simulation and array factor theory have been exploited. The HPNA fabrication is compatible with generic foundry technology.

Nearest comoment estimation with unobserved factors

We propose a minimum distance estimator for the higher-order comoments of a multivariate distribution exhibiting a lower dimensional latent factor structure. We derive the influence function of the proposed estimator and prove its consistency and asymptotic normality. The simulation study confirms the large gains in accuracy compared to the traditional sample comoments. The empirical usefulness of the novel framework is shown in applications to portfolio allocation under non-Gaussian objective functions and to the extraction of factor loadings in a dataset with mental ability scores.

Supplemental Material for Dimensional Latent Factor Structure of Psychopathology in Adults With Chronic Illness

Supplemental Material for Dimensional Latent Factor Structure of Psychopathology in Adults With Chronic Illness

Testing for Structural Changes in Large Dimensional Factor Models via Discrete Fourier Transform

We propose a new test for structural changes in large dimensional factor models via a discrete Fourier transform (DFT) approach. If structural changes occur, the conventional principal component analysis fails to estimate common factors and factor loadings consistently. The estimated residuals will contain information about structural changes. Therefore, we can compare the DFT of the estimated residuals with the null (zero) spectrum implied by no structural change. The proposed test is powerful against both smooth structural changes and abrupt structural breaks with a possibly unknown number of breaks and unknown break dates in factor loadings. It can detect a class of local alternatives at the parametric rate. As a result, the test is asymptotically more efficient than the existing tests in the factor model literature. And our test is also robust to serial and cross-sectional dependence of unknown form without having to estimate any long-run variance-covariance matrix. Moreover, it is easy to implement and tuning parameter-free. Monte Carlo studies demonstrate its reasonable size and excellent power in detecting various forms of structural changes in factor loadings. In an application to the U.S. macroeconomic data, we find significant and robust evidence of time-varying factor loadings.

Experiment of Telecom Customer’s Needs and Satisfaction Based on Kano Model

with the changing technology customers are more aware of services available to them. They access wide range of information of available products and services which has lead to change in their perception about services and service providers. This has made telecom a hard sector to survive for telecom service providers. These changes in behavioral intentions has made it necessary to us understand what all services customers feel a mandatory part of telecom service and what attract them to reuse the service. To study these customers needs Kano model was applied to category services of SERVQUAL model on four quadrant - attractive, one dimensional, must-be and indifferent. The result stated that network performance attract telecom customers the most and tangibility factors are the ones which service providers can minimize as customers are indifferent about them. Safety and security in transaction is one dimensional factor that can increase customer satisfaction. Must be attributes need to be continued to maintained customers stay with the telecom brands. Thus study tried to understand behavior of customers and identify factors that could increase customer satisfaction.

Large Dimensional Latent Factor Modeling with Missing Observations and Applications to Causal Inference

This paper develops the inferential theory for latent factor models estimated from large dimensional panel data with missing observations. We propose an easy-to-use all-purpose estimator for a latent factor model by applying principal component analysis to an adjusted covariance matrix estimated from partially observed panel data. We derive the asymptotic distribution for the estimated factors, loadings and the imputed values under an approximate factor model and general missing patterns. The key application is to estimate counterfactual outcomes in causal inference from panel data. The unobserved control group is modeled as missing values, which are inferred from the latent factor model. The inferential theory for the imputed values allows us to test for individual treatment effects at any time under general adoption patterns where the units can be affected by unobserved factors.

Memory Effects in Quantum Metrology.

Quantum metrology concerns estimating a parameter from multiple identical uses of a quantum channel. We extend quantum metrology beyond this standard setting and consider the estimation of a physical process with quantum memory, here referred to as a parametrized quantum comb. We present a theoretic framework of metrology of quantum combs, and derive a general upper bound of the comb quantum Fisher information. The bound can be operationally interpreted as the quantum Fisher information of a memoryless quantum channel times a dimensional factor. We then show an example where the bound can be attained up to a factor of 4. With the example and the bound, we show that memory in quantum sensors plays an even more crucial role in the estimation of combs than in the standard setting of quantum metrology.

INTERACTION OF THE LANTHANA, YTTRIA WITH ITERBIY AT TEMPERATURE 1100 °C

Using the methods of physicochemical analysis (XRD, petrography, SEM, X–ray microprobe analysis) phase equilibria were firstly investigated in the ternary system La 2 O 3 –Y 2 O 3 –Yb 2 O 3 at 1100 °C. The specimens were prepared in step 1-5 mol % from nitrate solutions with their subsequent evaporation and decomposition at 800 °C for 2 h. Powders were pressed at 10 MPa into pellets of 5 mm in diameter and 4 mm in height. To study phase relationships in the ternary system La2О3 – Y2O3 – Yb2О3 thermal treatment of as-prepared samples was carried at 1100 °С. X-ray diffraction analysis of the samples was performed by a powder method at room temperature (CuKa radiation). The scanning speed of 0.05-0.1 ° 2q/min was employed in the 15° to 90 ° 2q range. The effective precision of the measurements was ± 0.0002 nm. Lattice parameters were refined by least squares fitting using the LATTIC program. The crystal-optic characteristics of the obtained phases were determined under polarized microscopes “МІН-8” and Leica. The refraction indісes were measured in immersion liquids (solution of arsenic tribromide in methylene iodide or alloys of sulfur with selenium) with accuracy ± 0.02. The solid solutions based on various polymorphous forms of constituent phases and ordered phase with a structure of the perovskite-type of LaYO3 (LaYbO3) were revealed in the system. The boundaries of mutual solubility and concentration dependences the lattice parameters for all phases have been determined. The isothermal sections of the phase diagrams for the La 2 O 3 –Y 2 O 3 –Yb 2 O 3 systems at 1100°C are characterized by the presence of one three-phase (B +C + R), four single-phase (A- La 2 O 3 , B- La 2 O 3 , R, C- Y 2 O 3 (Yb 2 O 3 )) and two-phase (A + B, B+ R, C + R, B + C) regions. The solid solutions are formed by the mechanism of the isovalent substitution. The stability of ordered phases and solid solutions are determined by the dimensional factor : in the LaYO 3 , the large size ions replace La 3+ ions, the smaller ions of the cerium series substitute both Y 3+ and La 3+ , where as all the mentioned rare earth ions may be replaced by Y 3+ ions. An ordered R-phase in the ternary system exists in the wider range of concentrations than in the binary system.

Alternative Model of Personality Disorders (DSM-5) Predicts Dropout in Inpatient Psychotherapy for Patients With Personality Disorder.

ObjectiveCriterion A serves as the fundamental diagnostic criterion of the Alternative Model of Personality Disorders in section III of the Diagnostic and Statistical Manual 5. Consisting of a self- and an interpersonal dimension, it defines the construct of personality functioning as a general and dimensional factor of personality disorders. This study aimed to explore criterion A along with well-established treatment dropout predictors, e.g., sociodemographic factors, personality disorder diagnosis, symptom severity, and the therapeutic alliance.MethodsThe sample consisted of 132 patients diagnosed with personality disorder in a psychotherapeutic inpatient treatment. Cox proportional hazard regression models and a lasso model were applied.Results28% of the sample prematurely discontinued treatment. The risk for dropout was 2.3 times higher for patients with high impairments in self-functioning as assessed with criterion A. Moreover, a positive therapist-rated therapeutic alliance was associated with a lower dropout risk.ConclusionThe study suggests criterion A is a useful clinical indicator by identifying patients with personality disorder with a higher risk for dropout. An individualized therapeutic approach for such patients might be required.

Does the presence of a S. Salivarius biofilm influence the tooth-zirconia pair triboactivity? An in-vitro study

This study aims to determine if the presence of Streptococcus salivarius biofilm changes the tribological response of the tooth/zirconia contact pair. Reciprocating pin-on-plate wear tests were carried out at 37 °C and pH 7, using an appropriate lubricant to simulate an oral environment accounting for the presence of a S. salivarius surface biofilm. Reference wear tests were also carried out in artificial saliva with and without added glucose in aseptic conditions. Tests lasted a total of 21600 cycles under an applied normal load of 1.98 N. Human molar cusps served as pins while medical grade Y-TZP samples were used as sliding plates. Microscopy and profilometry readings were employed for the characterization of pristine and worn surfaces. Enamel/zirconia contact during sliding is notably affected by the presence of a Streptococcus salivarius biofilm. When compared to aseptic reference testing with and without added glucose, the S. salivarius biofilm decreased the dimensional wear factor by 87% and 81% respectively, and decreased the coefficient of friction by 77% and 68% respectively. Results clearly show that a streptococcus biofilm can change the tribological performance of a dental system. This work demonstrates that the presence of biofilm should be appreciated for a dental tribo-sytem, and the authors propose that further works regarding dental wear testing be carried out introducing asepsis level as a fundamental testing parameter.

Ultradense protium p(0) and deuterium D(0) and their relation to ordinary Rydberg matter: a review

The extremely large density of ultra-dense hydrogen H(0) has been proved in numerous experiments by three laser-induced methods, namely Coulomb explosions observed by particle time-of-flight (TOF) and TOF mass spectrometry, rotational emission spectroscopy in the visible, and annihilation-like meson ejecting nuclear reaction processes. The density of H(0) at the quite common spin level s = 2 is of the order of 100 kg cm−3. The theory of ultra-dense hydrogen H(0) is described briefly, especially the ‘mixed’ spin quantum number s and its relation to the internuclear distances. The orbital angular momentum of the bonding electrons in H(0) is l = 0, which gives the H(0) designation. At s = 2 with electron total angular momentum L = ħ, the internuclear distance is 2.24 pm, and at s = 1 thus L = ħ/2, it is as small as 0.56 pm. The internuclear distances are measured by optical rotational spectroscopy with a precision as good as 10−3, thus with femtometer resolution. The dimensional factor (ratio of internuclear distance to the electron orbit radius) was determined to be 2.9 by electrostatic stability calculations for ordinary Rydberg matter. This value is found to be valid with high precision also for H(0) clusters with different shapes. Superfluidity and a Meissner effect at room temperature are only found for the long chain clusters H2N(0), while the small H3(0) and H4(0) clusters do not have any super properties. Instead, they are the clusters in which most of the nuclear reaction processes take place. These processes give meson showers (most types of kaons and pions) and, after meson decay, large fluxes of muons and other leptons. Published applications of these results already exist in the field of nuclear reactions, energy production (patented fusion reactor), space physics (the solar wind), and in astrophysics (dark matter and the interstellar medium).

Is problematic exercise really problematic? A dimensional approach.

Though moderate exercise has numerous health benefits, some individuals may become excessively preoccupied with exercise, endorsing features akin to "addiction." The aim of this study was to evaluate the relationships between problematic exercise (viewed dimensionally), quality of life, and psychological measures. Young adults were recruited from an established population-based cohort in the United Kingdom and completed an online survey. The factor structure of the Exercise Addiction Inventory (EAI) was characterized. Relationships between dimensional EAI factor scores and other variables (impulsivity, compulsivity, emotional dysregulation) were elicited. Six hundred and forty-two individuals took part in the study (mean age 23.4 years, 64.7% female). The EAI yielded two factors - a "general factor" and a "relationship conflict factor." Both EAI factor scores were associated with disordered eating, impulsivity (UPPS), and compulsivity (CHI-T). Only the relationship conflict factor score was significantly associated with impaired quality of life (all domains) and with maladaptive personality traits (emotional dysregulation and obsessive-compulsive personality disorder traits). Few participants met conventional threshold for full exercise addiction (1.1%). Higher problematic exercise scores, in a sample largely free from exercise addiction, were associated with impulsive and compulsive personality features, emotional dysregulation, and disordered eating. Further research is needed to examine whether these results generalize to other populations (such as gym attendees) and are evident using more rigorous in-person clinical assessment rather than online assessment. Longitudinal research is needed to examine both positive and negative impacts of exercise, since moderate exercise may, in fact, be useful for those with impulsive/compulsive tendencies, by dampening negative emotional states or substituting for other more damaging types of repetitive habit.