277 research outputs found
LGBTI variations in crime reporting: how sexual identity influences decisions to call the cops
No full textResearch shows that people vary in their willingness to report crime to police depending on the type of crime experienced, their gender, age, and their race or ethnicity. Whether or not lesbian, gay, bisexual, transgender, and intersex (LGBTI) and heterosexual people vary in their willingness to report crime to the police is not well understood in the extant literature. In this article, I examine variations in LGBTI respondents' attitudes, subjective norms, and perceived behavioral control on their intentions to report crimes to the police. Drawing on a survey of LGBTI individuals sampled from a Gay Pride community event and online LGBTI community forums (N = 329), I use quantitative statistical methods to examine whether LGBTI people's beliefs in police homophobia are also directly associated with the behavioral intention to report crime. Overall, the results indicate that LGBTI and heterosexual people differ significantly in their intention to report crime to the police, and that a belief in police homophobia strongly influences LGBTI people's intention to underreport crime to the police
Effects of strontium content on microstructure and ionic conductivity of samarium-doped ceria
No full textSamarium doped ceria is a material which can achieve a high oxygen ion conductivity making it a promising electrolyte material for applications such as solid oxide fuel cells. Co-doping ceria with strontium alongside another dopant such as samarium has been the subject of a number of studies. Most suggest that strontium co-doping will improve the ionic conductivity compared to singly doped materials. However, there are a number of apparent inconsistencies in the literature due to the range of preparation methods employed. This meant that the true effects of Strontium co-doping were difficult to ascertain. To address this, two different compositional series of strontium and samarium co-doped ceria were studied. The first compositional series, Ce₀.₈₋ₓSm₀.₂SrₓO[sub(1.9-x-δ)], partially replaced Ce with Sr and was designed to be comparable to existing materials. The second series, Ce₀.₈₊ₓSm₀.₂₋₂ₓSrₓO[sub(1.9-δ)], was designed to have a constant oxygen vacancy concentration in order to study the intrinsic effects on conductivity. In order to control for impurities and microstructural effects a high purity synthesis method was used and microstructural studies of all the materials were performed.
The individual effects of strontium co-doping on conductivity were separated out allowing explanations of the contradictions in the existing literature. None of the codoped materials studied showed increases in conductivity compared to the singly doped materials at a typical fuel cell operating temperature. It was concluded that strontium co-doping of ceria can mitigate the deleterious effects on conductivity of silicon impurities or poor microstructure, but not improve the conductivity beyond that of the best singly doped ceria electrolytes
Are Early Warning Scores Useful Predictors for Mortality and Morbidity in Hospitalised Acutely Unwell Older Patients? : A Systematic Review
No full textFunding: No funding was gained to directly support the conduct of this study. Toby Smith is supported by funding from the National Institute for Health Research (NIHR) Oxford Health Biomedical Research Centre. The views expressed are those of the author(s) and not necessarily those of the NIHR. Acknowledgments: We thank Samuel Ronald Neal who proofread the manuscript.Peer reviewe
Beginning teachers’ mathematical knowledge: What is needed?
No full textOver the past decade there has been growing interest in describing and measuring the kinds of mathematical knowledge needed by teachers. Such efforts are in parallel with the development of national standards for teachers, indicating levels of expectation across the years of teachers’ careers. This presentation provides an opportunity for teacher educators and teachers to consider the nature of mathematical knowledge needed by beginning teachers at all levels of schooling. Discussion will be informed by data from an ALTC funded national project that aims to improve the quality of pre-service teachers’ outcomes in mathematics and by the AAMT Standards framework
Retinitis Pigmentosa GTPase Regulator (RPGR) protein isoforms in mammalian retina:insights into X-linked Retinitis Pigmentosa and associated ciliopathies
No full textMutations in the cilia-centrosomal protein Retinitis Pigmentosa GTPase Regulator (RPGR) are a frequent cause of retinal degeneration. The RPGR gene undergoes complex alternative splicing and encodes multiple protein isoforms. To elucidate the function of major RPGR isoforms (RPGR 1-19 and RPGR ORF15), we have generated isoform-specific antibodies and examined their expression and localization in the retina. Using sucrose-gradient centrifugation, immunofluorescence and co-immunoprecipitation methods, we show that RPGR isoforms localize to distinct sub-cellular compartments in mammalian photoreceptors and associate with a number of cilia-centrosomal proteins. The RCC1-like domain of RPGR, which is present in all major RPGR isoforms, is sufficient to target it to the cilia and centrosomes in cultured cells. Our findings indicate that multiple isotypes of RPGR may perform overlapping yet somewhat distinct transport-related functions in photoreceptors
Effects on microstructure and ionic conductivity of the co-doping with strontium and samarium of ceria with constant oxygen vacancy concentration
No full textPartially substituted cerias are attractive materials for use as electrolytes in intermediate-temperature solid oxide fuel cells (SOFCs). Ceria doped with Sm or Gd has been found to have high ionic conductivities. However, there is interest in whether doping with multiple elements could lead to materials with higher ionic conductivities. The present study looks at the effects of co-doping Sr and Sm in ceria. A compositional series, Ce0.8+xSm0.2−2xSrxO2−δ (with x = 0–0.08), designed to have a constant oxygen vacancy concentration, was successfully prepared using the citrate–nitrate complexation method. A solubility limit of ~5 cation% Sr was found to impact material structure and conductivity. For phase-pure materials, with increasing Sr content, sinterability increased slightly and intrinsic conductivity decreased roughly linearly. The grain boundaries of phase-pure materials showed only a very small blocking effect, linked to the high-purity synthesis method employed, while at high %Sr, they became more blocking due to the presence of a SrCeO3 impurity. Grain capacitances were found to be 50–60 pF and grain boundary capacitances, 5–50 nF. The variation in the bulk capacitance with Sr content was small, and the variation in grain boundary capacitance could be explained by the variation in grain size. Slight deviations at high %Sr were attributed to the SrCeO3 impurity. In summary, in the absence of deleterious effects due to poor microstructure or impurities, such as Si, there is no improvement in conductivity on co-doping with Sr and Sm.Peer reviewe
Effects of strontium content on the microstructure and ionic conductivity of samarium-doped ceria
No full textWe thank the School of Chemistry, University of St Andrews for a PhD studentship for TS.Due to its high oxygen ion conductivity at elevated temperatures, samarium-doped ceria (SDC) is a very promising material for application in solid state electrochemical devices and especially in the electrolytes of solid oxide fuel cells. Several prior studies have reported a further improvement in the ionic conductivity of SDC on doping with small amounts of strontium. It is suggested that strontium acts as a sintering aid—improving the microstructure of SDC—and as a scavenger of silicon impurities, decreasing its tendency to form resistive phases at grain boundaries. However, because of the range of preparation methods and the resulting differences in microstructure and silicon levels, some inconsistencies exist in the literature. Furthermore, the effect of strontium on the intrinsic (bulk) conductivity of SDC is not often discussed. To address these issues, a systematic, combined microstructural and conductivity study has been performed on a compositional series with a range of strontium contents, Ce0.8−xSm0.2SrxO2−δ (x = 0, 0.002, 0.005, 0.01, 0.02, 0.03, 0.04). A low temperature synthesis affording products with low silicon was employed. Total bulk and grain boundary conductivity data were obtained over a wide temperature range. Increasing strontium content caused a general decrease in total and intrinsic conductivity, but there was an improvement in grain boundary conductivity at the lowest strontium levels. These results were interpreted by reference to the microstructures using, among other parameters, the blocking, and normalised blocking, factors.Peer reviewe
Studies of clinically applicable human tolerogenic dendritic cells and PD-L2 genetic modification of human islet allograft to promote graft tolerance.
No full textIslet transplantation is a developing therapy for type 1 diabetic patients (T1D), which has been limited by problems associated with hypoxia, poor revascularisation and allograft rejection. Immunosuppressive agents used to prevent rejection are associated with severe side effects including islet toxicity, increased susceptibility to the development of cancer, infections and cardio-vascular problems. In order for islet transplantation to be used widely as a potentially curative treatment for T1D there is a need to develop novel therapies to treat allograft rejection without the use of immunosuppressive agents. In chapter 3, the immunomodulatory effects of IFN-γ on human monocyte-derived DC were investigated, using a standard 7-day in vitro DC propagation protocol. IFN-γ was shown to exert its immunomodulatory function on monocytes early during DC differentiation (IFNγ-DC[subscript]D0), resulting in an immature DC (iDC) phenotype with reduced expression of maturation markers CD83 and RelB. IFNγ-DC[subscript]D0 induced a state of T-cell hyporesponsiveness in a MLR, whilst IFN-γ treatment at day 5 (IFNγ-DC[subscript]D5) did not modulate DC function. The ability of IFN-γ to promote the generation of maturation arrested DC, could potentially serve as a cellular therapy for transplant rejection. However DC propagation using the standard 7-10 day protocol is not clinically applicable in the islet transplant setting. In chapter 4, a 'FAST-DC' protocol to promote the rapid generation of tolerogenic DC was investigated and used to generate IFNγ modulated DC in 48h. These IFNγ-DC featured an iDC phenotype similar to that seen in chapter 3. Maturation arrested IFNγ-DC caused significant T-cell hyporesponsiveness and promoted a higher frequency of CD4+CD25+ Foxp3[superscript]HI T-regulatory cells. IFNγ-DC primed T-cells were shown to be functionally suppressive in an antigen specific manner. It was also confirmed that IFN-γ reduced the phosphorylation of IL-4 activated STAT-6, which in turn affected the downstream gene expression of Interferon regulatory factor 4 (IRF4). IFNγ-DC were also investigated in vivo, where a humanised model of islet allo-transplantation model was developed. Diabetic NOD-SCID mice were transplanted with human islets and challenged with donor-derived DC and allogeneic PBMNC. After 21 days post transplantation, there was no significant change to euglycaemic state, between the tested groups. Genetic modification of the allograft is an alternative therapy to protecting the graft from the recipient‟s immune system. In chapter 5, human islets were genetically modified with programmed cell death ligand 2 (PD-L2), an inhibitory molecule known inhibit T-cell immune responses. Two recombinant adenovirus constructs carrying the PD-L2 gene were generated. One construct encoded a soluble isoform, while the other expressed a full transmembrane PD-L2 molecule. Adenoviral transduction did not affect the viability or insulin producing capacity of islets. Interestingly, soluble PD-L2 was more efficient at inducing signalling by 1000 fold, compared to the transmembrane isoform. In summary, this thesis demonstrated the timing of IFN-γ exposure is crucial in determining the function of DC and their maturational state, where IFN-γ exposure only during DC differentiation resulted in the inhibition of DC maturation. Secondly, the combination of IFN-γ and a FAST-DC protocol, enabled the generation of tolerogenic DC in 48h, making DC therapy more clinically applicable. Finally, the induced expression of soluble PD-L2 by human islets potently signals through human PD-1, which may provide the basis for the protection of islets from allo- and auto T-cell responses.Thesis (Ph.D.) -- University of Adelaide, School of Medicine, 201
Cosmic ambivalence: Academia’s relationship to the popular
No full textIn keeping with academia’s place as one of society’s principal sources of authority, it has a hard time acknowledging the value of popular culture. This negative attitude goes back a very long way: writing in the 1st century AD, Plutarch recounts the great lawmaker Solon telling a play’s author, Thespis: “if we allow ourselves to praise and honour make-believe like this, the next thing will be to find it creeping into our serious business.
A Simple, Affordable, Do-It-Yourself Method for Measuring Soil Maximum Water Holding Capacity
No full textThere is an increasing need for accessible methods to monitor soil health. Our primary objective was to evaluate an accessible, do-it-yourself method for measuring the maximum water holding capacity – we call this the funnel, filter paper, and drainage (MWHCFFPD) method. First, we compared MWHCFFPD to the water desorption method via pressure cells (WHCPC), routinely used for generating soil water retention curves, using 10 soils from a wide range of textures (4–55% clay). Second, we tested the sensitivity of the MWHCFFPD to methodological variations likely encountered by citizen scientists. The two methods were quite comparable in precision, with mean coefficient of variances of 3.5% and 4.4% for the FFPD and water desorption method, respectively. The MWHCFFPD and WHCPC methods were comparable, with MWHCFFPD best correlating to WHCPC at −2.45 kPa (R2 = 0.98). The MWHCFFPD method is somewhat sensitive to some methodological modifications, most notably variation in water source, but with standardized protocols could be scientifically robust. Overall, MWHCFFPD can be used as a simple and affordable test of sieved soil structure and organic matter, and thus has potential to expand soil health monitoring.This article is published as Jessica T. Nelson, Toby A. Adjuik, E. Britt Moore, Andy D. VanLoocke, Alam Ramirez Reyes & Marshall D. McDaniel (2023) A Simple, Affordable, Do-It-Yourself Method for Measuring Soil Maximum Water Holding Capacity, Communications in Soil Science and Plant Analysis, DOI: 10.1080/00103624.2023.2296988. © 2023 The Author(s). This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/).
A dataset associated with this study is available at https://doi.org/10.25380/iastate.24898005.v1</p
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