A systematic review of practice-, provider-, and patient-level determinants impacting Asian-Americans' human papillomavirus vaccine intention and uptake.

INTRODUCTION: Asian-Americans have been documented to have low human papillomavirus (HPV) vaccine initiation and completion. No research has attempted to examine underlying mechanisms of HPV vaccine uptake disparities among Asian-Americans. Using the P3 (practice, provider, and patient) model, this study aimed to identify practice-, provider-, and patient-level determinants of Asian-Americans' HPV vaccine intention and uptake. METHODS: We conducted a systematic review of published literature regarding practice-, provider- and patient-level determinants of vaccine intention (e.g., intention, willingness, or acceptability) and uptake (e.g., initiation or completion). Eligible studies were those presenting empirical/original data, focusing on Asian populations in the U.S., including outcomes related to HPV vaccine intention and uptake, and analyzing data on factors associated with these outcomes separately for Asian groups. RESULTS: Twenty-six studies (19 quantitative and 7 qualitative studies) were included in the review. Most commonly studied subgroups were Koreans (n = 9), Chinese (n = 6), and Cambodians (n = 5). Studies showed varied prevalence across subgroups (intention: 23.4%-72%; initiation: 14%-67%; completion: 9%-63%). Only 3 studies included measurements of practice-level determinants (language services, insurance policy). Twelve studies measured provider-level determinants (most commonly documented: HPV vaccine recommendation). All studies measured patient-level determinants (most commonly documented: HPV and HPV vaccine knowledge, perceived safety, perceived susceptibility, and perceived relationship between HPV vaccine and sexual activity). CONCLUSIONS: Existing research on determinants of HPV vaccine intention and uptake among Asian-Americans currently lacks measurements of practice-level constructs and perspectives of clinic staff and providers, which are needed to guide system-level interventions and provider training. Data regarding patient-level determinants suggest that interventions for Asian-American populations can focus on providing educational information in culturally-appropriate manners, leveraging familial influences, and attending to access-related or cultural beliefs about HPV vaccine. Interventions should take into account varied vaccine intention and uptake prevalence in different Asian subgroups.

Bandgap tuning by using a lattice distortion induced by two symmetries that coexist in a quantum dot.

Among the interests in the application of quantum dots (QDs), the bandgap tuning is of key importance in controlling their material properties. The bandgap of a QD can be adjusted by adopting a variety of different physicochemical methods. Herein, a novel way of the bandgap tuning is developed in an Ag2S-based QD system by suitably quenching the transformation from monoclinic Ag2S to cubic Ag and by subsequently inducing a lattice-distorted region of ≈1-nm-scale in a QD. The two distinct crystalline phases of Ag2S and Ag coexisting with the lattice-distorted region are experimentally demonstrated by visually showing this remarkable coexistence in a QD. A new approach is presented to the bandgap tuning (2.51 to 1.64 eV) and enhancing optical properties by suitably tailoring the degree of the lattice-distorted region in a QD. This conceptual method could pave a new way to utilizing quantum effects in various QD applications.

NiO resistive random access memory nanocapacitor array on graphene.

In this study, a NiO RRAM nanocapacitor array was fabricated on a graphene sheet, which was on a Nb-doped SrTiO(3) substrate containing terraces with a regular interval of about 100 nm and an atomically smooth surface. For the formation of the NiO RRAM nanocapacitor (Pt/NiO/graphene capacitor) array, an anodic aluminum oxide (AAO) nanotemplate with a pore diameter of about 30 nm and an interpore distance of about 100 nm was used. NiO and Pt were subsequently deposited on the graphene sheet. The NiO RRAM nanocapacitor had a diameter of about 30 +/- 2 nm and a thickness of about 33 +/- 3 nm. Typical unipolar switching characteristics of the NiO RRAM nanocapacitor array were confirmed. The NiO RRAM nanocapacitor array on graphene exhibited lower SET and RESET voltages than that on a bare surface of Nb-doped SrTiO(3).

Self-formed exchange bias of switchable conducting filaments in NiO resistive random access memory capacitors.

We report on the ferromagnetism of conducting filaments formed in a NiO thin film, which exhibited a typical bistable resistive switching characteristic. The NiO thin film showed an antiferromagnetic hysteresis loop for a high resistive state (R(OFF)). However, for a low resistive state (R(ON)), the conducting filaments exhibited a ferromagnetic hysteresis loop for the field cooling. The ferromagnetic hysteresis behavior of the R(ON) state reveals switchable exchange coupling between the ferromagnetic Ni conducting filaments and the antiferromagnetic NiO layer.

New cryogenic phase transitions in SrSnO3.

Strontium stannate is under study as an ultra-stable dielectric material for microelectronic applications at low temperatures. It is known to have a remarkably temperature-independent dielectric constant from 27 K to room temperature. However, we report anomalies in the Raman spectra, dielectric response, and differential thermal analysis of strontium stannate compatible with a structural phase transition at 160 K. Further anomalies are seen in calorimetric and Raman data (but not dielectric data) that suggest another phase transition at 270 K. A preliminary x-ray powder diffraction study confirms a small change in the pseudo-cubic lattice constant a(T) at the lower transition.

Dip-pen lithography of ferroelectric PbTiO(3) nanodots.

Dip-pen nanolithography of ferroelectric PTO nanodots is described. This position-controlled dip-pen nanolithography using a silicon nitride cantilever produced an array of ferroelectric nanodots with a minimum lateral dimension of approximately 37 nm on a Nb-doped SrTiO(3) substrate. This minimum-sized PTO dot is characterized by single-domain epitaxial growth with an enhanced tetragonality (c/a ratio) of 1.08.

Heteroepitaxial ferroelectric ZnSnO3 thin film.

We investigated the ferroelectric characteristics of an epitaxial perovskite ZnSnO(3) thin film on a (111) SrRuO(3)/(111) SrTiO(3) substrate fabricated by pulsed laser deposition. We confirmed that the ZnSnO(3) thin film was epitaxially grown on the substrate, forming large terraces on the surface of the ZnSnO(3) thin film. The ZnSnO(3) thin film exhibited a high ferroelectric polarization of approximately 47 microC/cm(2), which was further supported by first-principles calculations.

Layered perovskites with giant spontaneous polarizations for nonvolatile memories.

A series of titanate-based layered perovskites having large values of the spontaneous polarization P(s) were developed for their applcations to nonvolatile ferroelectric random access memories. Among these, the Nd-modified bismuth titanate [Bi(4-x)Nd(x)Ti(3)O(12) (BNdT)] system exhibited the most remarkable ferroelectric properties. The c-axis oriented BNdT capacitor was characterized by a switchable remanent polarization 2P(r) of over 100 microC/cm(2) and imprinting and fatigue-free behavior. The active Ti site responsible for the giant P(s) was identified with the help of Rietveld analysis, x-ray absorption near-edge structure study, and ab initio quantum computations.