Extrinsic models for the dielectric response of CaCu{3}Ti{4}O{12}

The large, temperature-independent, low-frequency dielectric constant recently observed in single-crystal CaCu{3}Ti{4}O{12} is most plausibly interpreted as arising from spatial inhomogenities of its local dielectric response. Probable sources of inhomogeneity are the various domain boundaries endemic in such materials: twin, Ca-ordering, and antiphase boundaries. The material in and neighboring such boundaries can be insulating or conducting. We construct a decision tree for the resulting six possible morphologies, and derive or present expressions for the dielectric constant for models of each morphology. We conclude that all six morphologies can yield dielectric behavior consistent with observations and suggest further experiments to distinguish among them.Comment: 9 pages, with 1 postscript figure embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/mc_ext/index.htm

Evaluation of A Biological Agent For Controlling Basidiomycete Attack of Douglas-fir and Southern Pine

A biological control agent (Binab®) containing Trichoderma polysporum and T. harzianum was evaluated for its ability to prevent or arrest attack of loblolly pine (Pinus taeda) sapwood and Douglas-fir (Pseudotsuga menziesii) heartwood by five Basidiomycetes commonly isolated from poles in service. Studies of Lentinus lepideus were included for comparison. In general, the biocontrol agents performed well against L. lepideus and other brown-rot fungi out of ground contact, but they did not completely eliminate most of the test fungi. The biological control agents had little effect on L. lepideus when the wood was exposed to soil. In addition, the biocontrol agents had little effect on white-rot fungi, which are an important component of the microflora in decaying poles. Results suggest that Binab® is not suitable for remedial decay control without supplemental treatments that favor growth and activity of Trichoderma

Neural correlates and predictors of speech and language development in infants at elevated likelihood for autism: a systematic review

Autism spectrum disorder (ASD) is an increasingly prevalent and heterogeneous neurodevelopmental condition, characterized by social communicative differences, and a combination of repetitive behaviors, focused interests, and sensory sensitivities. Early speech and language delays are characteristic of young autistic children and are one of the first concerns reported by parents; often before their child’s second birthday. Elucidating the neural mechanisms underlying these delays has the potential to improve early detection and intervention efforts. To fill this gap, this systematic review aimed to synthesize evidence on early neurobiological correlates and predictors of speech and language development across different neuroimaging modalities in infants with and without a family history of autism [at an elevated (EL infants) and low likelihood (LL infants) for developing autism, respectively]. A comprehensive, systematic review identified 24 peer-reviewed articles published between 2012 and 2023, utilizing structural magnetic resonance imaging (MRI; n = 2), functional MRI (fMRI; n = 4), functional near-infrared spectroscopy (fNIRS; n = 4), and electroencephalography (EEG; n = 14). Three main themes in results emerged: compared to LL infants, EL infants exhibited (1) atypical language-related neural lateralization; (2) alterations in structural and functional connectivity; and (3) mixed profiles of neural sensitivity to speech and non-speech stimuli, with some differences detected as early as 6 weeks of age. These findings suggest that neuroimaging techniques may be sensitive to early indicators of speech and language delays well before overt behavioral delays emerge. Future research should aim to harmonize experimental paradigms both within and across neuroimaging modalities and additionally address the feasibility, acceptability, and scalability of implementing such methodologies in non-academic, community-based settings

Nanoscale Smoothing and the Analysis of Interfacial Charge and Dipolar Densities

The interface properties of interest in multilayers include interfacial charge densities, dipole densities, band offsets, and screening-lengths, among others. Most such properties are inaccesible to direct measurements, but are key to understanding the physics of the multilayers. They are contained within first-principles electronic structure computations but are buried within the vast amount of quantitative information those computations generate. Thus far, they have been extracted from the numerical data by heuristic nanosmoothing procedures which do not necessarily provide results independent of the smoothing process. In the present paper we develop the theory of nanosmoothing, establishing procedures for both unpolarized and polarized systems which yield interfacial charge and dipole densities and band offsets invariant to the details of the smoothing procedures when the criteria we have established are met. We show also that dipolar charge densities, i. e. the densities of charge transferred across the interface, and screening lengths are not invariant. We illustrate our procedure with a toy model in which real, transversely averaged charge densities are replaced by sums of Gaussians.Comment: 30 pages, 15 figures, 4 table

N-representability and stationarity in time-dependent density functional theory

To construct an N-representable time-dependent density-functional theory, a generalization to the time domain of the Levy-Lieb (LL) constrained search algorithm is required. That the action is only stationary in the Dirac-Frenkel variational principle eliminates the possibility of basing the search on the action itself. Instead, we use the norm of the partial functional derivative of the action in the Hilbert space of the wave functions in place of the energy of the LL search. The electron densities entering the formalism are $N$-representable, and the resulting universal action functional has a unique stationary point in the density at that corresponding to the solution of the Schr\"{o}dinger equation. The original Runge-Gross (RG) formulation is subsumed within the new formalism. Concerns in the literature about the meaning of the functional derivatives and the internal consistency of the RG formulation are allayed by clarifying the nature of the functional derivatives entering the formalism.Comment: 9 pages, 0 figures, Phys. Rev. A accepted. Introduction was expanded, subsections reorganized, appendix and new references adde

Towards a first principles description of phonons in Ni50_{50}Pt50_{50} disordered alloys: the role of relaxation

Using a combination of density-functional perturbation theory and the itinerant coherent potential approximation, we study the effects of atomic relaxation on the inelastic incoherent neutron scattering cross sections of disordered Ni$_{50}$Pt$_{50}$ alloys. We build on previous work, where empirical force constants were adjusted {\it ad hoc} to agree with experiment. After first relaxing all structural parameters within the local-density approximation for ordered NiPt compounds, density-functional perturbation theory is then used to compute phonon spectra, densities of states, and the force constants. The resulting nearest-neighbor force constants are first compared to those of other ordered structures of different stoichiometry, and then used to generate the inelastic scattering cross sections within the itinerant coherent potential approximation. We find that structural relaxation substantially affects the computed force constants and resulting inelastic cross sections, and that the effect is much more pronounced in random alloys than in ordered alloys.Comment: 8 pages, 3 eps figures, uses revtex

Outcome Measures in Adult Vulvar Lichen Sclerosus:A Systematic Review

Objectives:Core outcome domains (CODs) for treatment of adult vulvar lichen sclerosus (VLS) have recently been established through a Delphi study. A number of measuring tools are available for evaluating VLS. The aim of this study is to identify available standardized measurement tools for the major CODs for VLS that have recently been defined, namely, physical findings and quality of life (QoL) specific to VLS. Materials and Methods: A systematic search through September 8, 2023, for measuring tools applicable to VLS regarding physical findings and QoL including sexual function or sexual well-being and self-image was performed. Results: Thirty-five studies were included in the systematic review describing 26 tools covering the following 6 outcome domains: QoL-general health, QoL-lichen sclerosus specific, symptoms, clinical signs, emotional impact, and sexual functioning. Conclusions: In current research, there is no uniformity in use of measurement tools for evaluating VLS. The established CODs to evaluate treatment of VLS are applicable for evaluating disease course as well. A comprehensive study to reach consensus regarding measurement of physical findings, QoL-lichen sclerosus specific, sexuality, and self-image taking the predetermined CODs and other factors such as age into account is needed.</p

Growing up with juvenile vulvar lichen sclerosus, the experiences and care needs of adult women with lichen sclerosus since childhood:a qualitative exploration

BACKGROUND: Vulvar Lichen Sclerosus (VLS) is a chronic remitting condition affecting the genital skin of females of all ages. Although qualitative studies have been conducted focusing on women with VLS in mid-life or older, less is known about the experiences of individuals with VLS from childhood or adolescence onward.OBJECTIVE: To gain understanding of the experiences of women with a history of juvenile VLS (JVLS) regarding the impact of the disease on their personal lives, and their experiences and needs regarding care and guidance.METHODS: A qualitative study was conducted consisting of 27 in-depth face-to-face interviews with adult women with a histologically confirmed history of JVLS, striving for maximum variation and saturation. Interviews were audio-taped and transcribed verbatim. A thorough thematic content analysis was performed.RESULTS: Three main themes were identified. I. Varying impact of living with JVLS: Women experienced diverse emotional and physical impact, from shame and denial to complete acceptance, from restrictions in daily functioning to no limitations. They felt hindered by their own lack of knowledge about JVLS, and generally expressed a positive influence of sharing their experiences with people close to them. II. Finding one's way in care and guidance: While navigating care and guidance, women often felt hindered by knowledge gaps among health care professionals (HCPs), lack of continuity in care and guidance, lack of life-stage adjusted and future-oriented information provision, inadequate guidance around life events, and insufficient monitoring of determinants of therapy adherence. III. Need for patient-tailored care: Patients stressed the need for age-appropriate and life-phase adjusted information, guidance around life-events and compassionate contact with knowledgeable HCPs, aware of the determinants of therapy adherence and influencing factors.CONCLUSIONS: Age-appropriate life-phase adjusted individually tailored care for women diagnosed with VLS in childhood or adolescence is needed. Care and guidance from childhood onward should encompass a standard of care adapted to the individual as needs change over time. This involves taking interpersonal differences into account, including differences in support network and coping strategies. These findings demonstrate the need for improving awareness and knowledge about (J)VLS among HCPs, especially primary care providers, and among the general public.</p