Methodological innovations and challenges in the Kinsey Institute National Survey Pilot Project

Abstract: Despite the growth of mixed methods, little attention has focused on the specific challenges of conducting mixed methods research on sexual experience and perceptions of sexuality. This paper's purpose is to discuss the exploratory sequential design of, and methodological considerations originally arising from, a mixed methods pilot project that explored the possibility of updating components of Alfred Kinsey's mid-20th century research on US men and women. This pilot project consisted of three phases: (1) cognitive interviews, (2) two modalities of computer-based surveys conducted in two settings with two samples, and (3) debriefing interviews with selected survey participants from phase two coupled with ethnographic observations. We describe the phases, focusing on how multiple methods facilitated the design and assessment of our pilot project. We end by highlighting methodological considerations relevant to our mixed methods approach--phase timing, research environment, longitudinal design, data security and privacy, and cost--and their implications for sexuality researchers

Molecular and evolutionary basis of O-antigenic polysaccharide-driven phage sensitivity in environmental pseudomonads.

Pseudomonas protegens CHA0, a bacterial strain able to suppress plant pathogens as well as efficiently kill lepidopteran pest insects, has been studied as a biocontrol agent to prevent ensuing agricultural damage. However, the success of this method is dependent on efficient plant colonization by the bacterial inoculant, while it faces competition from the resident microbiota as well as predators such as bacteriophages. One of these naturally occurring phages, ΦGP100, was found to drastically reduce the abundance of CHA0 once inoculated into plant microcosms, resulting in the loss of plant protection effect against a phytopathogen. Here, we investigated the molecular determinants implicated in the interaction between CHA0 and the phage ΦGP100 using a high-density transposon-sequencing approach. We show that lipopolysaccharide cell surface decorations, specifically the longer OBC3-type O-antigenic polysaccharide (O-PS, O-antigen) of the two dominant O-PS of CHA0, are essential for the attachment and infection of ΦGP100. Moreover, when exploring the distribution of the OBC3 cluster in bacterial genomes, we identified several parts of this gene cluster that are conserved in phylogenetically distant bacteria. Through heterologous complementation, we integrated an OBC3-type gene copy from a phylogenetically distant bacterium and were able to restore the phage sensitivity of a CHA0 mutant which lacked the ability to form long O-PS. Finally, we evidence that the OBC3 gene cluster of CHA0 displays a high genomic plasticity and likely underwent several horizontal acquisitions and genomic rearrangements. Collectively, this study underlines the complexity of phage-bacteria interactions and the multifunctional aspect of bacterial cell surface decorations. IMPORTANCE The application of plant-beneficial microorganisms to protect crop plants is a promising alternative to the usage of chemicals. However, biocontrol research often faces difficulties in implementing this approach due to the inconsistency of the bacterial inoculant to establish itself within the root microbiome. Beneficial bacterial inoculants can be decimated by the presence of their natural predators, notably bacteriophages (also called phages). Thus, it is important to gain knowledge regarding the mechanisms behind phage-bacteria interactions to overcome this challenge. Here, we evidence that the major long O-antigenic polysaccharide (O-PS, O-antigen) of the widely used model plant-beneficial bacterium Pseudomonas protegens CHA0 is the receptor of its natural predator, the phage ΦGP100. We examined the distribution of the gene cluster directing the synthesis of this O-PS and identified signatures of horizontal gene acquisitions. Altogether, our study highlights the importance of bacterial cell surface structure variation in the complex interplay between phages and their Pseudomonas hosts

Theory of Exciton Recombination from the Magnetically Induced Wigner Crystal

We study the theory of itinerant-hole photoluminescence of two-dimensional electron systems in the regime of the magnetically induced Wigner crystal. We show that the exciton recombination transition develops structure related to the presence of the Wigner crystal. The form of this structure depends strongly on the separation $d$ between the photo-excited hole and the plane of the two-dimensional electron gas. When $d$ is small compared to the magnetic length, additional peaks appear in the spectrum due to the recombination of exciton states with wavevectors equal to the reciprocal lattice vectors of the crystal. For $d$ larger than the magnetic length, the exciton becomes strongly confined to an interstitial site of the lattice, and the structure in the spectrum reflects the short-range correlations of the Wigner crystal. We derive expressions for the energies and the radiative lifetimes of the states contributing to photoluminescence, and discuss how the results of our analysis compare with experimental observations.Comment: 10 pages, no figures, uses Revtex and multicol.st

Determining Magnetic Nanoparticle Size Distributions from Thermomagnetic Measurements

Thermomagnetic measurements are used to obtain the size distribution and anisotropy of magnetic nanoparticles. An analytical transformation method is described which utilizes temperature-dependent zero-field cooling (ZFC) magnetization data to provide a quantitative measurement of the average diameter and relative abundance of superparamagnetic nanoparticles. Applying this method to self-assembled MnAs nanoparticles in MnAs-GaAs composite films reveals a log-normal size distribution and reduced anisotropy for nanoparticles compared to bulk materials. This analytical technique holds promise for rapid assessment of the size distribution of an ensemble of superparamagnetic nanoparticles.Comment: Correction Appl. Phys. Lett. 98, 216103 (2011

Hard Instances of the Constrained Discrete Logarithm Problem

The discrete logarithm problem (DLP) generalizes to the constrained DLP, where the secret exponent $x$ belongs to a set known to the attacker. The complexity of generic algorithms for solving the constrained DLP depends on the choice of the set. Motivated by cryptographic applications, we study sets with succinct representation for which the constrained DLP is hard. We draw on earlier results due to Erd\"os et al. and Schnorr, develop geometric tools such as generalized Menelaus' theorem for proving lower bounds on the complexity of the constrained DLP, and construct sets with succinct representation with provable non-trivial lower bounds

Evolution of magnetic polarons and spin-carrier interactions through the metal-insulator transition in Eu1−x_{1-x}Gdx_{x}O

Raman scattering studies as functions of temperature, magnetic field, and Gd-substitution are used to investigate the evolution of magnetic polarons and spin-carrier interactions through the metal-insulator transition in Eu$_{1-x}$Gd$_{x}$O. These studies reveal a greater richness of phase behavior than have been previously observed using transport measurements: a spin-fluctuation-dominated paramagnetic (PM) phase regime for T $>$ T$^{*}$ $>$ T$_{C}$, a two-phase regime for T $<$ T$^{*}$ in which magnetic polarons develop and coexist with a remnant of the PM phase, and an inhomogeneous ferromagnetic phase regime for T $<$ T$_{C}$

Interpersonal interactions in instrumental lessons: teacher/students verbal and non-verbal behaviours

This study examined verbal and non-verbal teacher/student interpersonal interactions in higher education instrumental music lessons. Twenty-four lessons were videotaped and teacher/ student behaviours were analysed using a researcher-designed instrument. The findings indicate predominance of student and teacher joke among the verbal behaviours with no substantial gender differences between males and females. Deceit cues were the most frequent among the non-verbal behaviours, with the males displaying more gestures of deceit than the females. Other gender differences include the female students using courting signals towards both teacher groups and the female teachers showing interest towards the male students. The presence of positive verbal and negative non-verbal behaviours highlights the mixed messages present in teaching. Implications for instrumental teaching practice include greater focus on gender differences in interpersonal interactions and visual cues to improve communication and teacher/student relationship in the instrumental studio

Sexuality and Affection among Elderly German Men and Women in Long-Term Relationships: Results of a Prospective Population-Based Study

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.The study was funded by the German Federal Ministry for Families, Senior Citizens, Women and Youth (AZ 314-1722-102/16; AZ 301-1720-295/2), the Ministry for Science, Research and Art Baden-Württemberg, and the University of Rostock (FORUN 989020; 889048)