Gender stereotypes have descriptive components, or beliefs about how males and females typically act, as well as prescriptive components, or beliefs about how males and females should act. For ...example, women are supposed to be nurturing and avoid dominance, and men are supposed to be agentic and avoid weakness. However, it is not clear whether people hold prescriptive gender stereotypes about children of different age groups. In addition, research has not addressed prescriptive gender stereotypes for the elderly. The current research measured prescriptive gender stereotypes for children, adults, and elderly men and women in 3 studies to (a) compare how prescriptive gender stereotypes change across age groups and (b) address whether stereotypes of males are more restrictive than stereotypes of females. Students (Studies 1 and 2) and community members (Study 3), which were all U.S. and majority White samples, rated how desirable it was for different target groups to possess a list of characteristics from 1
) to 9 (
). The target age groups included toddlers, elementary-aged, adolescent, young adult, adult, and elderly males and females. The list of 21 characteristics was created to encompass traits and behaviors relevant across a wide age range. In a meta-analysis across studies, prescriptive stereotypes were defined as characteristics displaying a sex difference of
> 0.40 and an average rating as desirable for positive prescriptive stereotypes (PPS) or undesirable for negative proscriptive stereotypes (NPS) for male or females of each age group. Results replicated previous research on prescriptive stereotypes for adults: Women should be communal and avoid being dominant. Men should be agentic, independent, masculine in appearance, and interested in science and technology, but avoid being weak, emotional, shy, and feminine in appearance. Stereotypes of boys and girls from elementary-aged to young adults still included these components, but stereotypes of toddlers involved mainly physical appearance and play behaviors. Prescriptive stereotypes of elderly men and women were weaker. Overall, boys and men had more restrictive prescriptive stereotypes than girls and women in terms of strength and number. These findings demonstrate the applicability of prescriptive stereotypes to different age groups.
In applying social role theory to account for the content of a wide range of stereotypes, this research tests the proposition that observations of groups' roles determine stereotype content (Eagly & ...Wood, 2012). In a novel test of how stereotypes can develop from observations, preliminary research collected participants' beliefs about the occupational roles (e.g., lawyer, teacher, fast food worker, chief executive officer, store clerk, manager) in which members of social groups (e.g., Black women, Hispanics, White men, the rich, senior citizens, high school dropouts) are overrepresented relative to their numbers in the general population. These beliefs about groups' typical occupational roles proved to be generally accurate when evaluated in relation to data from the Bureau of Labor Statistics. Then, correlational studies predicted participants' stereotypes of social groups from the attributes ascribed to group members' typical occupational roles (Studies 1a, 1b, and 1c), the behaviors associated with those roles (Study 2), and the occupational interest profile of the roles (Study 3). As predicted by social role theory, beliefs about the attributes of groups' typical roles were strongly related to group stereotypes on both communion and agency/competence. In addition, an experimental study (Study 4) demonstrated that when social groups were described with changes to their typical social roles in the future, their projected stereotypes were more influenced by these future roles than by their current group stereotypes, thus supporting social role theory's predictions about stereotype change. Discussion considers the implications of these findings for stereotype change and the relation of social role theory to other theories of stereotype content.
Interest in developing high performance lithium-ion rechargeable batteries has motivated research in precise control over the composition, phase, and morphology during materials synthesis of battery ...active material particles for decades. Coprecipitation, as one of the most reported methods in the literature to produce precursors for lithium-ion battery active materials, has drawn attention due to its simplicity, scalability, homogeneous mixing at the atomic scale, and tunability over particle morphology. This highlight summarizes the advancements that have been made in producing crystalline particles of tunable and complex morphologies via coprecipitation for use as lithium-ion battery precursor materials. Comparison among different crystallization reagents, solution conditions that influence the properties of crystal particles, and the fundamental knowledge from equilibrium and/or kinetic study of the coprecipitation processes, are systematically discussed. The research reports and guiding principles summarized in this highlight are meant to improve selections made by researchers to efficiently determine synthesis conditions. In addition, it is desired that the methods applied from the study of crystallization will inspire researchers to pursue further investigation of the nucleation and growth mechanisms of these coprecipitation processes, which will be necessary to achieve truly predictive particle synthesis.
This
meta-analysis examined the extent to which stereotypes of leaders are culturally
masculine. The primary studies fit into 1 of 3 paradigms: (a) In
Schein's
(1973)
think manager-think male ...paradigm, 40 studies with 51
effect sizes compared the similarity of male and leader stereotypes and the
similarity of female and leader stereotypes; (b) in Powell and Butterfield's (1979)
agency-communion paradigm, 22 studies with 47 effect
sizes compared stereotypes of leaders' agency and communion; and (c) in
Shinar's
(1975)
masculinity-femininity paradigm, 7 studies with 101
effect sizes represented stereotypes of leadership-related occupations on a
single masculinity-femininity dimension. Analyses implemented appropriate
random and mixed effects models. All 3 paradigms demonstrated overall
masculinity of leader stereotypes: (a) In the think manager-think male
paradigm, intraclass correlation = .25 for the women-leaders similarity
and intraclass correlation = .62 for the men-leaders similarity; (b) in
the agency-communion paradigm, g = 1.55, indicating
greater agency than communion; and (c) in the masculinity-femininity
paradigm, g = 0.92, indicating greater masculinity than the
androgynous scale midpoint. Subgroup and meta-regression analyses indicated that
this masculine construal of leadership has decreased over time and was greater
for male than female research participants. In addition, stereotypes portrayed
leaders as less masculine in educational organizations than in other domains and
in moderate- than in high-status leader roles. This article considers the
relation of these findings to Eagly and
Karau's (2002) role congruity theory, which proposed
contextual influences on the incongruity between stereotypes of women and
leaders. The implications for prejudice against women leaders are also
considered.
A new type of non-aqueous redox couple without carbon additives for flow batteries is proposed and the target anolyte chemistry is demonstrated. The so-called “Solid Dispersion Redox Couple” ...incorporates solid electroactive materials dispersed in organic lithium-ion battery electrolyte as its flowing suspension. In this work, a unique and systematic characterization approach has been used to study the flow battery redox couple in half cell demonstrations relative to a lithium electrode. An electrolyte laden with Li4Ti5O12 (LTO) has been characterized in multiple specially designed lithium half cell configurations. The flow battery redox couple described in this report has relatively low viscosity, especially in comparison to other flow batteries with solid active materials. The lack of carbon additive allows characterization of the electrochemical properties of the electroactive material in flow without the complication of conductive additives and unambiguous observation of the electrorheological coupling in these dispersed particle systems.
Display omitted
•A carbon-free solid dispersion redox couple for a new type of flow battery is demonstrated.•A unique characterization approach is used to study dispersion flow batteries.•LTO suspensions with different loadings show shear-thinning behavior.•Electrochemical behavior of LTO suspensions shows LTO loading dependence.
Considerable overlap has been identified in the risk factors, comorbidities and putative pathophysiological mechanisms of Alzheimer disease and related dementias (ADRDs) and type 2 diabetes mellitus ...(T2DM), two of the most pressing epidemics of our time. Much is known about the biology of each condition, but whether T2DM and ADRDs are parallel phenomena arising from coincidental roots in ageing or synergistic diseases linked by vicious pathophysiological cycles remains unclear. Insulin resistance is a core feature of T2DM and is emerging as a potentially important feature of ADRDs. Here, we review key observations and experimental data on insulin signalling in the brain, highlighting its actions in neurons and glia. In addition, we define the concept of 'brain insulin resistance' and review the growing, although still inconsistent, literature concerning cognitive impairment and neuropathological abnormalities in T2DM, obesity and insulin resistance. Lastly, we review evidence of intrinsic brain insulin resistance in ADRDs. By expanding our understanding of the overlapping mechanisms of these conditions, we hope to accelerate the rational development of preventive, disease-modifying and symptomatic treatments for cognitive dysfunction in T2DM and ADRDs alike.
Due to their high energy density, lithium-ion batteries have been the state-of-the-art energy storage technology for many applications. Energy density can be further improved by engineering of the ...electrode architecture and microstructure, in addition to more common improvements via materials chemistry. All active material (AAM) electrodes consist of only the electroactive material that stores energy, and such electrodes have advantages to conventional composite processing with regards to improved mechanical stability at increased thicknesses and ion transport properties. However, the absence of binders and composite processing makes the electrode more vulnerable to electroactive materials with volume change upon cycling. Also, the electroactive material must have sufficient electronic conductivity to avoid large matrix electronic overpotentials during electrochemical cycling. TiNb2O7 (TNO) and MoO2 (MO) are electroactive materials with potential advantages as AAM electrodes due to relatively high volumetric energy density. TNO has higher energy density, and MO has much higher electronic conductivity, and thus a multicomponent blend of these materials was evaluated as an AAM anode. Herein, blends of TNO and MO as AAM anodes were investigated, where this is the first use of a multicomponent AAM anode. Electrodes that had both TNO and MO had the highest volumetric energy density, rate capability, and cycle life relative to single component TNO and MO anodes. Thus, using multicomponent materials provides a route to improve AAM electrochemical systems.
Abstract Background The utilization of hip arthroscopy continues to increase in the United States. The purpose of this study was to examine trends in hip arthroscopy procedures and outcomes. Methods ...We performed a retrospective cohort study using Optum Labs Data Warehouse administrative claims data. The cohort comprised 10,042 privately insured enrollees aged 18-64 years who underwent a hip arthroscopy procedure between 2005 and 2013. Utilization trends were examined using age-, sex- and calendar-year specific hip arthroscopy rates. Outcomes were examined using the survival analysis methods and included subsequent hip arthroscopy and total hip arthroplasty. Results Hip arthroscopy rates increased significantly over time from 3.6 per 100,000 in 2005 to 16.7 per 100,000 in 2013. The overall 2-year cumulative incidence of subsequent hip arthroscopy and total hip arthroplasty were 11% and 10%, respectively. In the subset of patients in whom laterality of the subsequent procedure could be determined, about half of the subsequent hip arthroscopy procedures (46%) and almost all of the THA procedures (94%) were on the same side. Decreasing age was significantly associated with the risk of subsequent arthroscopy (p<0.01), whereas increasing age was significantly associated with the subsequent risk of total hip arthroplasty (p<0.01). The 5-year cumulative incidence of total hip arthroplasty reached as high as 35% among individuals aged 55-64 years. Conclusion The utilization of hip arthroscopy procedures increased dramatically over the last decade in the 18-64 year old privately insured population, with the largest increase in younger age groups. Future studies are warranted to understand the determinants of the large increase in utilization of hip arthroscopy and outcomes.
For centuries, the eye has fascinated scientists and philosophers alike, and as a result the visual system has always been at the forefront of integrating cutting-edge technology in research. We are ...again at a turning point at which technical advances have expanded the range of organisms we can study developmentally and deepened what we can learn. In this new era, we are finally able to understand eye development in animals across the phylogenetic tree. In this Review, we highlight six areas in comparative visual system development that address questions that are important for understanding the developmental basis of evolutionary change. We focus on the opportunities now available to biologists to study the developmental genetics, cell biology and morphogenesis that underlie the incredible variation of visual organs found across the Metazoa. Although decades of important work focused on gene expression has suggested homologies and potential evolutionary relationships between the eyes of diverse animals, it is time for developmental biologists to move away from this reductive approach. We now have the opportunity to celebrate the differences and diversity in visual organs found across animal development, and to learn what it can teach us about the fundamental principles of biological systems and how they are built.
Assemblies formed by solid particles at interfaces have been widely studied because they serve as models of molecular phenomena, including molecular self-assembly. Solid particles adsorbed at ...interfaces also provide a means of stabilizing liquid-liquid emulsions and synthesizing materials with tunable mechanical, optical, or electronic properties. Whereas many past studies have investigated colloids at interfaces of isotropic liquids, recently, new types of intercolloidal interactions have been unmasked at interfaces of liquid crystals (LCs): The long-range ordering of the LCs, as well as defects within the LCs, mediates intercolloidal interactions with symmetries that differ from those observed with isotropic liquids. Herein, we report the decoration of interfaces formed between aqueous phases and nematic LCs with prescribed densities of solid, micrometer-sized particles. The microparticles assemble into chains with controlled interparticle spacing, consistent with the dipolar symmetry of the defects observed to form about each microparticle. Addition of a molecular surfactant to the aqueous phase results in a continuous ordering transition in the LC, which triggers reorganization of the microparticles, first by increasing the spacing between microparticles within chains and ultimately by forming two-dimensional arrays with local hexagonal symmetry. The ordering transition of the microparticles is reversible and is driven by surfactant-induced changes in the symmetry of the topological defects induced by the microparticles. These results demonstrate that the orderings of solid microparticles and molecular adsorbates are strongly coupled at the interfaces of LCs and that LCs offer the basis of methods for reversible, chemosensitive control of the interfacial organization of solid microparticles.
PDF
