5,636 research outputs found
Neutralising antibody response in domestic cats immunised with a commercial feline immunodeficiency virus (FIV) vaccine
Across human and veterinary medicine, vaccines against only two retroviral infections have been brought to market successfully, the vaccines against feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV). FeLV vaccines have been a global success story, reducing virus prevalence in countries where uptake is high. In contrast, the more recent FIV vaccine was introduced in 2002 and the degree of protection afforded in the field remains to be established. However, given the similarities between FIV and HIV, field studies of FIV vaccine efficacy are likely to advise and inform the development of future approaches to HIV vaccination.<p></p>
Here we assessed the neutralising antibody response induced by FIV vaccination against a panel of FIV isolates, by testing blood samples collected from client-owned vaccinated Australian cats. We examined the molecular and phenotypic properties of 24 envs isolated from one vaccinated cat that we speculated might have become infected following natural exposure to FIV. Cats vaccinated against FIV did not display broadly neutralising antibodies, suggesting that protection may not extend to some virulent recombinant strains of FIV circulating in Australia.<p></p>
Dmp1 lineage cells contribute significantly to periosteal lamellar bone formation induced by mechanical loading but are depleted from the bone surface during rapid bone formation
Previous work has shown that osteoprogenitor cells (Prx1+) and pre-osteoblasts (Osx+) contribute to mechanical loading-induced bone formation. However, the role of mature Dmp1-expressing osteoblasts has not been reported. In this study we assessed the contribution of osteoblast lineage cells to bone formation at an early time point following mechanical loading (day 8 from onset of loading). We labeled Osx-expressing and Dmp1-expressing cells in inducible Osx and Dmp1 reporter mice (iOsx-Ai9, iDmp1-Ai9), respectively, 3 weeks before loading. Mice were then loaded daily for 5 days (days 1-5) and were dosed with 5-ethynyl-2\u27-deoxyuridine (EdU) in their drinking water until euthanasia on day 8. Mice were loaded to lamellar and woven bone inducing stimulation (-7 N/1400 με, -10 N/2000 με) to assess differences in these processes. We found varied responses in males and females to the loading stimuli, inducing modest lamellar (females, -7 N), moderate lamellar (males, -10 N), and robust woven (females, -10 N) bone. Overall, we found that preexisting (ie, lineage positive) Osx-expressing and Dmp1-expressing cells contribute largely to the bone formation response, especially during modest bone formation, while our results stuggest that other (non-lineage-positive) cells support the sustained bone formation response during rapid bone formation. With moderate or robust levels of bone formation, a decrease in preexisting Osx-expressing and Dmp1-expressing cells at the bone surface occurred, with a near depletion of Dmp1-expressing cells from the surface in female mice loaded to -10 N (from 52% to 11%). These cells appeared to be replaced by lineage-negative cells from the periosteum. We also found a dose response in proliferation, with 17% to 18% of bone surface cells arising via proliferation in modest lamellar, 38% to 53% in moderate lamellar, and 59% to 81% in robust woven bone formation. In summary, our results show predominant contributions by preexisting Osx and Dmp1 lineage cells to loading-induced lamellar bone formation, whereas recruitment of earlier osteoprogenitors and increased cell proliferation support robust woven bone formation. © 2021 The Authors
Alignment Between Technology Acceptance And Instructional Design via Self-Efficacy
As organizations continue to implement new technology solutions, the need for both technology training and examining technology acceptance of new implementations are necessary to determine the success or failure of a project. Unfortunately, instructional design considerations generally do not address technology acceptance, and leading technology acceptance models only classify training as an external variable or facilitating condition, with limited consideration in prior research. In this paper, we examine potential integration points between instructional design theory and technology acceptance. Specifically, we examine prior research on self-efficacy, Kirkpatrick’s Model for Evaluating Training, Merrill’s Component Display Theory, and Merrill’s First Principles of Instruction
Duration of antibody response following vaccination against feline immunodeficiency virus
Objectives:
Recently, two point-of-care (PoC) feline immunodeficiency virus (FIV) antibody test kits (Witness and Anigen Rapid) were reported as being able to differentiate FIV-vaccinated from FIV-infected cats at a single time point, irrespective of the gap between testing and last vaccination (0–7 years). The aim of the current study was to investigate systematically anti-FIV antibody production over time in response to the recommended primary FIV vaccination series.
Methods:
First, residual plasma from the original study was tested using a laboratory-based ELISA to determine whether negative results with PoC testing were due to reduced as opposed to absent antibodies to gp40. Second, a prospective study was performed using immunologically naive client-owned kittens and cats given a primary FIV vaccination series using a commercially available inactivated whole cell/inactivated whole virus vaccine (Fel-O-Vax FIV, three subcutaneous injections at 4 week intervals) and tested systematically (up to 11 times) over 6 months, using four commercially available PoC FIV antibody kits (SNAP FIV/FeLV Combo [detects antibodies to p15/p24], Witness FeLV/FIV [gp40], Anigen Rapid FIV/FeLV [p24/gp40] and VetScan FeLV/FIV Rapid [p24]).
Results:
The laboratory-based ELISA showed cats from the original study vaccinated within the previous 0–15 months had detectable levels of antibodies to gp40, despite testing negative with two kits that use gp40 as a capture antigen (Witness and Anigen Rapid kits). The prospective study showed that antibody testing with SNAP Combo and VetScan Rapid was positive in all cats 2 weeks after the second primary FIV vaccination, and remained positive for the duration of the study (12/12 and 10/12 cats positive, respectively). Antibody testing with Witness and Anigen Rapid was also positive in a high proportion of cats 2 weeks after the second primary FIV vaccination (8/12 and 7/12, respectively), but antibody levels declined below the level of detection in most cats (10/12) by 1 month after the third (final) primary FIV vaccination. All cats tested negative using Witness and Anigen Rapid 6 months after the third primary FIV vaccination.
Conclusions and relevance:
This study has shown that a primary course of FIV vaccination does not interfere with FIV antibody testing in cats using Witness and Anigen Rapid, provided primary vaccination has not occurred within the previous 6 months. Consequently, Witness and Anigen Rapid antibody test kits can be used reliably to determine FIV infection status at the time of annual booster FIV vaccination to help detect ‘vaccine breakthroughs’ and in cats that have not received a primary course of FIV vaccination within the preceding 6 months. The duration of antibody response following annual booster FIV vaccination and the resulting effect on antibody testing using PoC kits needs to be determined by further research. The mechanism(s) for the variation in FIV antibody test kit performance remains unclear
Teachers\u27 Technological Pedagogical Knowledge and Learning Activity Types: Curriculum-Based Technology Integration Reframed
In this paper we critically analyze extant approaches to technology integration in teaching, arguing that many current methods are technocentric, often omitting sufficient consideration of the dynamic and complex relationships among content, technology, pedagogy, and context. We recommend using the technology, pedagogy, and content knowledge (TPACK) framework as a way to think about effective technology integration, recognizing technology, pedagogy, content and context as interdependent aspects of teachers’ knowledge necessary to teach content-based curricula effectively with educational technologies. We offer TPACK-based “activity types,” rooted in previous research about content-specific activity structures, as an alternative to existing professional development approaches and explain how this new way of thinking may authentically and successfully assist teachers’ and teacher educators’ technology integration efforts
Patient experience of general practice and use of emergency hospital services in England: regression analysis of national cross-sectional time series data.
BACKGROUND: The UK Government has introduced several national policies to improve access to primary care. We examined associations between patient experience of general practice and rates of visits to accident and emergency (A&E) departments and emergency hospital admissions in England. METHODS: The study included 8124 general practices between 2011-2012 and 2013-2014. Outcome measures were annual rates of A&E visits and emergency admissions by general practice population, according to administrative hospital records. Explanatory variables included three patient experience measures from the General Practice Patient Survey: practice-level means of experience of making an appointment, satisfaction with opening hours and overall experience (on 0-100 scales). The main analysis used random-effects Poisson regression for cross-sectional time series. Five sensitivity analyses examined changes in model specification. RESULTS: Mean practice-level rates of A&E visits and emergency admissions increased from 2011-2012 to 2013-2014 (310.3-324.4 and 98.8-102.9 per 1000 patients). Each patient experience measure decreased; for example, mean satisfaction with opening hours was 79.4 in 2011-2012 and 76.6 in 2013-2014. In the adjusted regression analysis, an SD increase in experience of making appointments (equal to 9 points) predicted decreases of 1.8% (95% CI -2.4% to -1.2%) in A&E visit rates and 1.4% (95% CI -1.9% to -0.9%) in admission rates. This equalled 301 174 fewer A&E visits and 74 610 fewer admissions nationally per year. Satisfaction with opening hours and overall experience were not consistently associated with either outcome measure across the main and sensitivity analyses. CONCLUSIONS: Associations between patient experience of general practice and use of emergency hospital services were small or inconsistent. In England, realistic short-term improvements in patient experience of general practice may only have modest effects on A&E visits and emergency admissions
Whooping crane demographic responses to winter drought focus conservation strategies
AbstractFocusing conservation strategies requires identifying the demographic parameters and environmental conditions affecting the growth of animal populations most. Therefore, we examined relationships between population demographics and winter drought (1950–2011) for endangered whooping cranes (Grus americana) wintering in Texas, USA. We modeled winter loss and its contribution to annual mortality as functions of winter drought, determined recruitment needed to maintain population growth after drought, and identified which demographic parameters underpin this population’s growth. Previous research assumed winter loss (i.e., birds missed in subsequent surveys) represented mortality. We show that loss includes temporary emigration to upland habitats, early migration, and incomplete detection. Despite this, we maintained this assumption to evaluate the relevance of winter mortality to population growth. We found that winter loss (β^=-0.308, SE=0.042) and its contribution to annual mortality (β^=-0.318, SE=0.047) increased with drought severity (Palmer hydrological drought index; PHDI). Given average recruitment (0.145, SD=0.090), this population increases 1.2% (95% CI=−2.9% to 4.2%) after extreme drought (PHDI=−4). No recruitment must occur for 3years with moderate to severe drought (PHDI<−2.5) to delay species’ recovery ≈7years. This scenario has not occurred since population monitoring began in 1938. Of the demographic parameters we examined, winter loss explained population growth least (14.4%; 95% CI=3.6–35.8%), and it was partially compensatory. Breeding–migratory mortality explained 42.2% (95% CI=19.1–61.5%) of population growth and recruitment 49.9% (95% CI=20.6–75.2%). Our results focus conservation on breeding and migratory periods, and deemphasize winter mortality and drought. On the wintering grounds, conservation of whooping cranes should emphasize maintaining coastal, upland, and interior habitats for this population
Conserved but flexible modularity in the zebrafish skull: implications for craniofacial evolvability
Morphological variation is the outward manifestation of development and provides fodder for adaptive evolution. Because of this contingency, evolution is often thought to be biased by developmental processes and functional interactions among structures, which are statistically detectable through forms of covariance among traits. This can take the form of substructures of integrated traits, termed modules, which together comprise patterns of variational modularity. While modularity is essential to an understanding of evolutionary potential, biologists currently have little understanding of its genetic basis and its temporal dynamics over generations. To address these open questions, we compared patterns of craniofacial modularity among laboratory strains, defined mutant lines and a wild population of zebrafish ( ). Our findings suggest that relatively simple genetic changes can have profound effects on covariance, without greatly affecting craniofacial shape. Moreover, we show that instead of completely deconstructing the covariance structure among sets of traits, mutations cause shifts among seemingly latent patterns of modularity suggesting that the skull may be predisposed towards a limited number of phenotypes. This new insight may serve to greatly increase the evolvability of a population by providing a range of 'preset' patterns of modularity that can appear readily and allow for rapid evolution
The Challenges of Implementing Project-based Learning in Middle Schools
Project-based learning is an instructional approach that requires teachers and students to work collaboratively to solve authentic problems guided by a driving question and often making use of technology for research and the presentation of findings. This study examined middle school teachers 19 perceptions associated with the implementation of project-based learning and explored the challenges teachers perceive they face when implementing project-based learning, the ways they respond to these challenges, and the role teachers perceive 21st Century skills play in a project-based learning implementation. The purpose of the study was to examine teachers 19 perceptions of for consideration of future implementations of project-based learning. The study was conducted at a suburban middle school outside Pittsburgh, PA. Forty-nine teachers responded to a questionnaire designed to collect data on their perceptions. The participants were asked to rate challenges they face against a set list of challenges developed through selected literature on project-based learning implementations (Bender, 2012; Markham, Larmer, & Ravitz, 2003). The participants were also asked to explain ways they respond to the perceived challenges and to rate the degree to which they perceived project-based learning addressed 21st Century skills as defined by the Partnership for 21st Century skills.
The researcher found that teachers perceived that time, meeting state accountability requirements, addressing the standards, implementing the project within the schools schedule and designing the project-based experience were most challenging when implementing project-based learning. The study also found that teachers either knew how to respond to challenges or expressed further concern about doing so. The 21st Century skills teachers perceived project-based learning addressed more effectively than more traditional methods of instruction were communication and collaboration, creativity and innovation, and critical thinking and problem solving.
The findings suggest that professional development may help alleviate some of the perceived challenges teachers face when implementing project-based learning. The study also suggests that 21st Century skills play a valuable role in project-based learning implementations and should be specifically addressed in the development and implementation of project-based learning experiences
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