24 research outputs found
Chemical heterogeneity in electroceramics: The good, the bad, and the difficult to characterize
As characterization techniques continue to advance, the materials community is reminded again and again that our samples are not as perfect as we generally describe them to be. This presentation will focus on Bi(Zn0.5Ti0.5)O3–BaTiO3-based ceramics in which subtle mesoscale cation gradients have been identified as a key factor in the phenomenal temperature- and field-stable permittivity of these unusual dielectrics as well as their remarkably high resistivity values and associated activation energies.[1,2] Earlier work has shown that the single perovskite phase that results after calcination of mixed oxides and carbonates is formed through a complex series of solid-state reactions (Figure 1),[3] and complementary sintering studies have strongly suggested that development of these complex microstructures with mesoscale heterogeneity is strongly dependent upon cation diffusion kinetics (Figure 2). Here, we report on the effects of reaction pathways during calcination on phase formation and microstructural development during sintering in ceramics of nominally identical xBi(Zn0.5Ti0.5)O3 – (1-x)BaTiO3 compositions. These results remind us once again that while often treated as such, material micro/meso/nanostructure is not a state function, and that local ion environments can be determined by processing steps, which can in turn profoundly and selectively affect phase formation, ion diffusion, microstructure development, and resultant properties.
This reinforces the need for multiple complementary characterization and measurement techniques for effective description of complex functional materials, and provides a cautionary tale for the budding age of computational materials discovery that real materials—and occasionally enabling performance—often live outside the realm of thermodynamic equilibrium
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Mapping the domains of human-animal interaction quality (QHAI)
Animal assisted activities (AAAs) have become increasingly popular on college campuses in the United States in response to prevalent mental health issues. While initial studies suggest positive program outcomes for students, little is known about how, under what conditions, and for whom AAAs are an effective means of preventing mental health issues. In particular, little is known about program mediators and moderators, including the impact of the quality of interactions between humans and animals during these programs. This study uses a symbolic interactionist perspective to explore the role of interaction quality within a college-based, animal-assisted stress prevention program. A grounded theory approach was used to identify behaviors indicative of interaction quality between humans and animals during programming. Results include descriptions of behaviors within categories according to handler behavior (e.g., engagement, warmth), dog behavior (e.g., engagement, avoidance), student behavior (e.g., engagement with dog), dynamic interactions (e.g., handler-dog connection), and group behavior (e.g., dispersion). Results will provide a foundation to support further exploration and assessment of human-animal interaction quality and potential implications for AAAs
The Effect of Composition and Structure on the Dissolution Rates in Water of Alkali- Alkaline Earth Borate Glasses
Fifteen different borate glasses with molar compositions 10X2O·10RO·80 B2O3, 15X2O·15CaO·70B2O3, and 20X2O·20CaO·60B2O3 (where X =Li, Na or K and R =Mg, Ca or Sr) were characterized using NMR, FTIR, and Raman spectroscopies. The fractions of boron tetrahedra (B4) were determined; 0.45 of the borate units in glasses with 60 and 70 mole% B2O3 were tetrahedral, compared to 0.29 in glasses with 80 mole% B2O3. The dissolution rate in 37 °C water was determined from glass powders by measuring the boron release rate using ICP-OES. Dissolution rate constants were determined using a contracting volume model for spherical particles. Glasses with 80 mole% B2O3 (fewer B4 units) dissolved about an order of magnitude faster than glasses with more B4 units. Glasses with greater field strength alkali (Li \u3c Na \u3c K) and alkaline earth (Ca \u3c Sr) ions dissolved 25-50% more slowly; Mg-containing glasses did not follow this field strength trend
The near-end of the institution of incapacitation?
The article is devoted to one of the basic, from the point of view of human rights, institutions of private law, namely the institution of incapacitation. Over the years, this institution has been the subject of analyzes, although too few, taking into account its significance. The article has been divided into two parts. The first discusses the currently applicable provisions of private law regarding incapacitation. The second part of the article is devoted to the analysis of the concept of proposed changes in the provisions on incapacitation. Both parts have been completed with tables to illustrate the most important issues related to the discussed topics. The author’s intention was to explain these provisions and proposed changes in the most accessible way, so as to enable the reader to read the article, regardless of his education. The interviews included in the study aim to answer the question whether the current provisions on legal incapacitation comply with basic human rights, or whether they have become somewhat "obsolete" and require thorough changes. The aim of the article was to draw readers' attention to the problem of the legal situation of mentally ill people and to the need to adjust legal regulations in this respect to the needs of modern times
Metoda szacowania rzeczywistej liczby ludności w strefie podmiejskiej. Przykład gminy Czernica (powiat wrocławski)
Residential suburbanization is one of the processes, which takes place on a large scale in the vicinity of large cities. The suburban areas of Wrocław are no exception, witnessing a dynamic influx of people and increased construction activity. This article strives to identify the scale of residential suburbanization based on the case study of Czernica municipality, which is part of the suburban area of Wrocław. The discusses the problem of population under estimations is attributed to the failure to comply with obligations of compulsory registration at the place of residence. It led to disparities between the actual local population size and the official statistical records. This analysis seeks to determine how many people actually reside in the Czernica municipality using a proprietary method of estimating the actual number of residents based on pooled statistical data on registered residence originating from the General Electronic Civil Registration System (the PESEL register) from 2012 and spatial data from the Topographic Database (BDOT) of 2013. The article presents the scale of population underestimation in the Czernica municipality in years 2012–2013 and possibilities and limitations in application of themethod constructed by authors in other suburban areas.
Jednym z procesów zachodzących intensywnie w otoczeniu dużych miast jest suburbanizacja rezydencjonalna. Nie inaczej jest w przypadku obszarów podmiejskich Wrocławia, gdzie obserwowany jest dynamiczny napływ ludności i wzmożony ruch budowlany. Celem artykułu była identyfikacja skali procesów suburbanizacji rezydencjonalnej na przykładzie gminy Czernica, stanowiącej część strefy podmiejskiej Wrocławia. Publikacja porusza problematykę niedoszacowania wielkości ruchu migracyjnego w otoczeniu dużych miast, wynikającą z niezgodności ewidencji ludności w odniesieniu do faktycznego miejsca zamieszkania. Wynika to z braku obowiązku meldunkowego przez co faktyczna liczba ludności różni się od tej wykazywanej w statystykach publicznych. Niniejszą analizę, ukazującą faktyczną liczbę mieszkańców gminy Czernica, przeprowadzono z zastosowaniem autorskiej metody szacowania rzeczywistej liczby ludności, wykorzystując zagregowane dane statystyczne o zameldowaniach z bazy Powszechnego Elektronicznego Systemu Ewidencji Ludności (re-jestr PESEL) oraz dane przestrzenne z Bazy Danych Obiektów Topograficznych (BDOT)
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Evaluation of Undergraduate Students' Responsiveness to a 4-Week University-Based Animal-Assisted Stress Prevention Program
An increase in the prevalence of stress among college students is compromising their mental health and academic success. One approach to stress prevention that has seen a surge in implementation is the use of university-based Animal Visitation Programs (AVPs). Despite their popularity and promising causal findings, program evaluations on students' responsiveness (e.g., enjoyment, attendance, perceptions on usefulness and behavioral change) have yet to be conducted. Using a mixed methods approach, this study reports results of a program evaluation embedded in a randomized controlled trial examining the efficacy of incorporating various levels (0%, 50% or 100%) of Human Animal Interaction (HAI) into a four-week long university-based stress prevention program resulting in three conditions: (1) Evidence-based Academic Stress Management content only (0% HAI), (2) Human Animal Interaction with therapy dogs only (100% HAI) and (3) equal combinations of Academic Stress Management and HAI (50% HAI). Responsiveness (e.g., enjoyment, usefulness, recommendation and behavioral change) was assessed quantitatively and qualitatively using self-reported survey data collected immediately following the program and again six weeks later. The results suggest that combining evidence-based content presentations with HAI was associated with higher levels of enjoyment, perceived usefulness, and likelihood of recommendation compared to presenting content presentation or HAI alone, although doing so did not result in differences in perceived behavioral change by condition. Themes of students' perceptions on the role of HAI in shaping program enjoyment, usefulness, recommendations and behavioral change were described
DNP Project: Improving No-Show Rates in Primary Care
Abstract
This paper explores the factors that contribute to no-show rates in the primary care setting and effective interventions to improve no-show rates. The average no-show rate in the primary care setting is 23%, (Dantas, Fleck, Olivaria, & Humacher 2018). In 2018, the no-show rate at the WeCare Clinic was 50-60%. A literature review was conducted to gather information regarding why patients choose to no-show their appointments, the common causes of high no-show rates, and effective interventions found to decrease no-show rates. We investigated the primary causes of a high no-show rate at the WeCare Clinic by interviewing staff and analyzing contributing factors at the site. We began implementing effective interventions based on our research including transportation resources, consistent front desk staff, and a reliable reminder system. The no-show rate decreased from 38.9 % in January 2019 to 30% in December of 2019. These sustainable and effective interventions have reduced WeCare’s no-show rate below that of the national average in the primary care setting
Evaluation of Undergraduate Students’ Responsiveness to a 4-Week University-Based Animal-Assisted Stress Prevention Program
An increase in the prevalence of stress among college students is compromising their mental health and academic success. One approach to stress prevention that has seen a surge in implementation is the use of university-based Animal Visitation Programs (AVPs). Despite their popularity and promising causal findings, program evaluations on students’ responsiveness (e.g., enjoyment, attendance, perceptions on usefulness and behavioral change) have yet to be conducted. Using a mixed methods approach, this study reports results of a program evaluation embedded in a randomized controlled trial examining the efficacy of incorporating various levels (0%, 50% or 100%) of Human Animal Interaction (HAI) into a four-week long university-based stress prevention program resulting in three conditions: (1) Evidence-based Academic Stress Management content only (0% HAI), (2) Human Animal Interaction with therapy dogs only (100% HAI) and (3) equal combinations of Academic Stress Management and HAI (50% HAI). Responsiveness (e.g., enjoyment, usefulness, recommendation and behavioral change) was assessed quantitatively and qualitatively using self-reported survey data collected immediately following the program and again six weeks later. The results suggest that combining evidence-based content presentations with HAI was associated with higher levels of enjoyment, perceived usefulness, and likelihood of recommendation compared to presenting content presentation or HAI alone, although doing so did not result in differences in perceived behavioral change by condition. Themes of students’ perceptions on the role of HAI in shaping program enjoyment, usefulness, recommendations and behavioral change were described