13,988 research outputs found
Child Adult Relationship Enhancement in Primary Care (PriCARE): Study design/protocol for a randomized trial of a primary care-based group parenting intervention to prevent child maltreatment
BACKGROUND: Child maltreatment (CM) is a pervasive public health problem and there is a critical need for brief, effective, scalable prevention programs. Problematic parent-child relationships lie at the heart of CM. Parents who maltreat their children are more likely to have punitive parenting styles characterized by high rates of negative interaction and ineffective discipline strategies with over-reliance on punishment. Thus, parenting interventions that strengthen parent-child relationships, teach positive discipline techniques, decrease harsh parenting, and decrease child behavioral problems hold promise as CM prevention strategies. Challenges in engaging parents, particularly low-income and minority parents, and a lack of knowledge regarding effective implementation strategies, however, have greatly limited the reach and impact of parenting interventions. Child Adult Relationship Enhancement in Primary Care (PriCARE)/Criando Niños con CARIĂO is a 6-session group parenting intervention that holds promise in addressing these challenges because PriCARE/CARIĂO was (1) developed and iteratively adapted with input from racially and ethnically diverse families, including low-income families and (2) designed specifically for implementation in primary care with inclusion of strategies to align with usual care workflow to increase uptake and retention.
METHODS: This study is a multicenter randomized controlled trial with two parallel arms. Children, 2-6 years old with Medicaid/CHIP/no insurance, and their English- and Spanish-speaking caregivers recruited from pediatric primary care clinics in Philadelphia and North Carolina will be enrolled. Caregivers assigned to the intervention regimen will attend PriCARE/CARIĂO and receive usual care. Caregivers assigned to the control regimen will receive usual care only. The primary outcome is occurrence of an investigation for CM by child protective services during the 48 months following completion of the intervention. In addition, scores for CM risk, child behavior problems, harsh and neglectful parenting behaviors, caregiver stress, and caregiver-child interactions will be assessed as secondary outcome measures and for investigation of possible mechanisms of intervention-induced change. We will also identify PriCARE/CARIĂO implementation factors that may be barriers and facilitators to intervention referrals, enrollment, and attendance.
DISCUSSION: By evaluating proximal outcomes in addition to the distal outcome of CM, this study, the largest CM prevention trial with individual randomization, will help elucidate mechanisms of change and advance the science of CM prevention. This study will also gather critical information on factors influencing successful implementation and how to optimize intervention referrals, enrollment, and attendance to inform future dissemination and practical applications.
TRIAL REGISTRATION: This trial was registered on ClinicalTrials.gov (NCT05233150) on February 1, 2022, prior to enrolling subjects
Structure of naturally hydrated ferrihydrite revealed through neutron diffraction and first-principles modeling
Ferrihydrite, with a ââtwo-lineââ x-ray diffraction pattern (2L-Fh), is the most amorphous of the iron oxides and is ubiquitous in both terrestrial and aquatic environments. It also plays a central role in the regulation and metabolism of iron in bacteria, algae, higher plants, and animals, including humans. In this study, we present a single-phase model for ferrihydrite that unifies existing analytical data while adhering to fundamental chemical principles. The primary particle is small (20â50 Ă
) and has a dynamic and variably hydrated surface, which negates long-range order; collectively, these features have hampered complete characterization and frustrated our understanding of the mineral's reactivity and chemical/biochemical function. Near and intermediate range neutron diffraction (NIMROD) and first-principles density functional theory (DFT) were employed in this study to generate and interpret high-resolution data of naturally hydrated, synthetic 2L-Fh at standard temperature. The structural optimization overcomes transgressions of coordination chemistry inherent within previously proposed structures, to produce a robust and unambiguous single-phase model
Nonlinear magnetoinductive transmission lines
Power transmission in one-dimensional nonlinear magnetic metamaterials driven
at one end is investigated numerically and analytically in a wide frequency
range. The nonlinear magnetic metamaterials are composed of varactor-loaded
split-ring resonators which are coupled magnetically through their mutual
inductances, forming thus a magnetoiductive transmission line. In the linear
limit, significant power transmission along the array only appears for
frequencies inside the linear magnetoinductive wave band. We present
analytical, closed form solutions for the magnetoinductive waves transmitting
the power in this regime, and their discrete frequency dispersion. When
nonlinearity is important, more frequency bands with significant power
transmission along the array may appear. In the equivalent circuit picture, the
nonlinear magnetoiductive transmission line driven at one end by a relatively
weak electromotive force, can be modeled by coupled
resistive-inductive-capacitive (RLC) circuits with voltage-dependent
capacitance. Extended numerical simulations reveal that power transmission
along the array is also possible in other than the linear frequency bands,
which are located close to the nonlinear resonances of a single nonlinear RLC
circuit. Moreover, the effectiveness of power transmission for driving
frequencies in the nonlinear bands is comparable to that in the linear band.
Power transmission in the nonlinear bands occurs through the linear modes of
the system, and it is closely related to the instability of a mode that is
localized at the driven site.Comment: 11 pages, 11 figures, submitted to International Journal of
Bifurcation and Chao
A Re-evaluation of Evidence for Light Neutral Bosons in Nuclear Emulsions
Electron-positron pair-production data obtained by bombardment of emulsion
detectors with either cosmic rays or projectiles with mass between one and 207
and kinetic energies between 18 GeV and 32 TeV have been re-analysed using a
consistent and conservative model of the background from electromagnetic pair
conversion. The combined data yield a spectrum of putative neutral bosons
decaying to e+e- pairs, with masses between 3 and 20 MeV/c^2 and femtosecond
lifetimes. The statistical significance against background for these "X-bosons"
varies between 2 and 8 sigma. The cross-section for direct production of
X-bosons increases slowly with projectile energy, remaining over 1,000 times
smaller the the pion production cross-section.Comment: major revision with improved figures; accepted by Int J Mod Phys
Chloroplast microsatellites: measures of genetic diversity and the effect of homoplasy
Chloroplast microsatellites have been widely used in population genetic
studies of conifers in recent years. However, their haplotype configurations
suggest that they could have high levels of homoplasy, thus limiting the power
of these molecular markers. A coalescent-based computer simulation was used to
explore the influence of homoplasy on measures of genetic diversity based on
chloroplast microsatellites. The conditions of the simulation were defined to
fit isolated populations originating from the colonization of one single
haplotype into an area left available after a glacial retreat. Simulated data
were compared with empirical data available from the literature for a species
of Pinus that has expanded north after the Last Glacial Maximum. In the
evaluation of genetic diversity, homoplasy was found to have little influence
on Nei's unbiased haplotype diversity (H(E)) while Goldstein's genetic distance
estimates (D2sh) were much more affected. The effect of the number of
chloroplast microsatellite loci for evaluation of genetic diversity is also
discussed
Slow roll in simple non-canonical inflation
We consider inflation using a class of non-canonical Lagrangians for which
the modification to the kinetic term depends on the field, but not its
derivatives. We generalize the standard Hubble slow roll expansion to the
non-canonical case and derive expressions for observables in terms of the
generalized slow roll parameters. We apply the general results to the
illustrative case of ``Slinky'' inflation, which has a simple, exactly
solvable, non-canonical representation. However, when transformed into a
canonical basis, Slinky inflation consists of a field oscillating on a
multi-valued potential. We calculate the power spectrum of curvature
perturbations for Slinky inflation directly in the non-canonical basis, and
show that the spectrum is approximately a power law on large scales, with a
``blue'' power spectrum. On small scales, the power spectrum exhibits strong
oscillatory behavior. This is an example of a model in which the widely used
solution of Garriga and Mukhanov gives the wrong answer for the power spectrum.Comment: 9 pages, LaTeX, four figures. (V2: minor changes to text. Version
submitted to JCAP.
Origin of Hawaiian Tholeiites: Trace Element Constraints
We report here geochemical studies of Hawaiian tholeiites and ultramafic xenoliths from Salt Lake Crater, Oahu. We focus attention on tholeiitic basalts that comprise the bulk of Hawaiian volcanoes. When the samples are screened to include only those lying neat the log-MgO (about 7 percent) end of olivine-control lines (Wright, 1971), tholeiites from individual volcanoes are remarkably uniform. On this basis, we show that, for tholeiites from six volcanoes, systematic geochemical differences exist that cannot be attributed to differentiation of these magmas from a common parental magma. Apparently there have been important differences in the processes of magma generation, source composition, or source mineral constitution.
Partial melting calculations based on REE contents emphasize these distinctions, but unique melting models are not presented. In these models, relative REE abundances in the source material is a major uncertainty. Nd isotopic studies of Hawaiian basalts require systematic differences in Sm/Nd for the source material of each volcano. Furthermore, the time-integrated Sm/Nd of the sources must be less than that in chondrites. REE analyses of Hawaiian garnet lherzolite xenoliths show that they have chondritic to light REE-enriched relative abundances with absolute contents (for light REE) about 3 to 8 times chondrites. These data obviously conflict with interpretations of the Nd isotopic data. Several possibilities follow: (1) the available xenoliths are not parental to tholeiite, (2) our simple interpretation of the Nd isotopic data is wrong, and (3) the source regions may have been invaded at geologically recent times by a light REE-enriched phase, in which case the xenoliths may represent the course material. If the xenoliths are characteristic of the source, partial melting calculations indicate that the tholeiites may be generated by 15 to 20 percent melting of garnet lherzolite and at the sane tune conform to constraints imposed by the REE and Ni contents and the partitioning of Fe and Mg between melts and residues. We propose that the primary tholeiitic magmas contain no more than about 12 percent MgO, and that erupted magmas probably fractionated less than 10 to 15 percent of olivine during ascent and storage in high-level chambers
Experimental and Theoretical Study of the Ultrafast Dynamics of a NiDy-Compound in DMF After UV/Vis Photoexcitation
We present a combined experimental and theoretical study of the ultrafast transient absorption spectroscopy results of a {NiDy}-compound in DMF, which can be considered as a prototypic molecule for single molecule magnets. We apply state-of-the-art ab initio quantum chemistry to quantitatively describe the optical properties of an inorganic complex system comprising ten atoms to form the chromophoric unit, which is further stabilized by surrounding ligands. Two different basis sets are used for the calculations to specifically identify two dominant peaks in the ground state. Furthermore, we theoretically propagate the compound\u27s correlated many-body wavefunction under the influence of a laser pulse as well as relaxation processes and compare against the time-resolved absorption spectra. The experimental data can be described with a time constant of several hundreds of femtoseconds attributed to vibrational relaxation and trapping into states localized within the band gap. A second time constant is ascribed to the excited state while trap states show lifetimes on a longer timescale. The theoretical propagation is performed with the density-matrix formalism and the Lindblad superoperator, which couples the system to a thermal bath, allowing us to extract relaxation times from first principles
Delivering reform in English healthcare: an ideational perspective
A variety of perspectives has been put forward to understand reform across healthcare systems. Recently, some have called for these perspectives to give greater recognition to the role of ideational processes. The purpose of this article is to present an ideational approach to understanding the delivery of healthcare reform. It draws on a case of English healthcare reform â the Next Stage Review led by Lord Darzi â to show how the delivery of its reform proposals was associated with four ideational frames. These frames built on the idea of âprogressâ in responding to existing problems; the idea of âprevailing policyâ in forming part of a bricolage of ideas within institutional contexts; the idea of âprescriptionâ as top-down structural change at odds with local contexts; and the idea of âprofessional disputesâ in challenging the notion of clinical engagement across professional groups. The article discusses the implications of these ideas in furthering our understanding of policy change, conflict and continuity across healthcare settings
APSIS - an Artificial Planetary System in Space to probe extra-dimensional gravity and MOND
A proposal is made to test Newton's inverse-square law using the perihelion
shift of test masses (planets) in free fall within a spacecraft located at the
Earth-Sun L2 point. Such an Artificial Planetary System In Space (APSIS) will
operate in a drag-free environment with controlled experimental conditions and
minimal interference from terrestrial sources of contamination. We demonstrate
that such a space experiment can probe the presence of a "hidden" fifth
dimension on the scale of a micron, if the perihelion shift of a "planet" can
be measured to sub-arc-second accuracy. Some suggestions for spacecraft design
are made.Comment: 17 pages, revtex, references added. To appear in Special issue of
IJMP
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