2,977 research outputs found
Prothonotary warbler nestling growth and condition inresponse to variation in aquatic and terrestrial preyavailability
Aquatic prey subsidies entering terrestrial habitats are well documented, but little is known about the degree to which these resources provide ïŹtness beneïŹts to riparian consumers. Riparian species take advantage of seasonal pulses of both terrestrial and aquatic prey, although aquatic resources are often over-looked in studies of how diet inïŹuences the reproductive ecology of these organisms. Ideally, the timing of resource pulses should occur at the time of highest reproductive demand. This study investigates the availability of aquatic(mayïŹy) and terrestrial (caterpillar) prey resources as well as the nestling diet of the prothonotary warbler (Protonotaria citrea) at two sites along the lower James River in Virginia during the 2014 breeding season. We found large differences in availability of prey items between the two sites, with one having significantly higher mayïŹy availability. Nestling diet was generally reïŹective of prey availability, and nestlings had faster mean growth rates at the site with higher aquatic prey availability. Terrestrial prey were fed more readily at the site with lower aquatic prey availability, and at this site, nestlings fed mayïŹies had higher mean growth rates than nestlings fed only terrestrial prey. Our results suggest that aquatic subsidies are an important resource for nestling birds and are crucial to understanding the breeding ecology of riparian species
HDAC inhibitors increase NRF2-signaling in tumour cells and blunt the efficacy of co-adminstered cytotoxic agents
The NRF2 signalling cascade provides a primary response against electrophilic chemicals and oxidative stress. The activation of NRF2-signaling is anticipated to have adverse clinical consequences; NRF2 is activated in a number of cancers and, additionally, its pharmacological activation by one compound can reduce the toxicity or efficiency of a second agent administered concomitantly. In this work, we have analysed systematically the ability of 152 research, pre-clinical or clinically used drugs to induce an NRF2 response using the MCF7-AREc32 NRF2 reporter. Ten percent of the tested drugs induced an NRF2 response. The NRF2 activators were not restricted to classical cytotoxic alkylating agents but also included a number of emerging anticancer drugs, including an IGF1-R inhibitor (NVP-AEW541), a PIM-1 kinase inhibitor (Pim1 inhibitor 2), a PLK1 inhibitor (BI 2536) and most strikingly seven of nine tested HDAC inhibitors. These findings were further confirmed by demonstrating NRF2-dependent induction of endogenous AKR genes, biomarkers of NRF2 activity. The ability of HDAC inhibitors to stimulate NRF2-signalling did not diminish their own potency as antitumour agents. However, when used to pre-treat cells, they did reduce the efficacy of acrolein. Taken together, our data suggest that the ability of drugs to stimulate NRF2 activity is common and should be investigated as part of the drug-development process
The piloting of an Academic Literacy Education Course (ALEC) to improve academic literacy of first semester undergraduate students in a Western Australian University
Widening participation has enabled access to higher education for an increasing number of students via a range of non-traditional pathways. Consequently, whilst having a large repertoire of skills and experience, these students may not have developed sufficient competence in academic literacy. The School of Nursing and Midwifery has a large proportion of such students who have difficulty making the academic transition to university study. It is believed that a âbuilt inâ approach to supporting these students to develop academic literacy will result in an improvement in their abilities to meet the requirements of the University and to better prepare them to graduate. This paper discusses the piloting of an Academic Literary Education Course (ALEC) for undergraduate students enrolled in the first semester unit of a three year health degree, within the disciplines of nursing and paramedical science. The students completed tests on academic literacy before and after completion of the ALEC. Particular areas of difficulty for students were found to be in referencing and unpacking the assessment question. When mean scores were compared between pre and post-tests in the same group, it was found there was a significant difference between scores at t value = -7,721, degrees of freedom = 181 with a p value of 0.000 or p value \u3c .001. Recommendations include incorporating the ALEC approach in further stages of the undergraduate degree program to support developing levels of academic literacy
Supporting Teachers in Times of Change: The Job Demands- Resources Model and Teacher Burnout During the COVID-19 Pandemic
Burnout in teachers has been broadly investigated, but no studies have investigated burnout in teachers during a pandemic. The current study is based on a survey of 1278 Canadian teachers and examined whether the Job Demands-Resources model was a useful lens for examining teacher burnout in this unprecedented context. Results supported the model in general terms in that most demands were most strongly correlated with the initial exhaustion stage of burnout. However, not all resources were most strongly associated with the later stages of burnout, suggesting that the examination of specific resources in the context of a pandemic as opposed to examining resources together as a latent variable contributes to development of a more refined model. Suggestions for supporting teachersâ welfare are provided
Historical microbiology: revival and phylogenetic analysis of the luminous bacterial cultures of M . W . B eijerinck
Luminous bacteria isolated by M artinus W . B eijerinck were sealed in glass ampoules in 1924 and 1925 and stored under the names P hotobacterium phosphoreum and â P hotobacterium splendidum â. To determine if the stored cultures were viable and to assess their evolutionary relationship with currently recognized bacteria, portions of the ampoule contents were inoculated into culture medium. Growth and luminescence were evident after 13 days of incubation, indicating the presence of viable cells after more than 80 years of storage. The B eijerinck strains are apparently the oldest bacterial cultures to be revived from storage. Multiâlocus sequence analysis, based on the 16S rRNA , gapA , gyrB , pyrH , recA , luxA , and luxB genes, revealed that the B eijerinck strains are distant from the type strains of P . phosphoreum , ATCC 11040 T , and V ibrio splendidus , ATCC 33125 T , and instead form an evolutionarily distinct clade of V ibrio . Newly isolated strains from coastal seawater in N orway, F rance, U ruguay, M exico, and J apan grouped with the B eijerinck strains, indicating a global distribution for this new clade, designated as the beijerinckii clade. Strains of the beijerinckii clade exhibited little sequence variation for the seven genes and approximately 6300 nucleotides examined despite the geographic distances and the more than 80 years separating their isolation. Gramânegative bacteria therefore can survive for many decades in liquid storage, and in nature, they do not necessarily diverge rapidly over time.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/88047/1/fem1177.pd
Student employability enhancement through fieldwork: purposefully integrated or a beneficial side effect?
Fieldwork provides opportunities for students to develop employability-enhancing transferable skills as well as technical, discipline-specific skills and disciplinary knowledge. However, the extent to which staff purposely plan transferable skills outcomes of field courses, and, therefore, whether they are communicated to students is unknown. We investigated whether staff intentionally plan transferable skills development opportunities into fieldwork by interviewing academic staff responsible for planning and leading residential field courses at a UK university. We also conducted a thematic analysis of associated module specifications and teaching materials to understand whether transferable skills were signposted to colleagues and students. Our findings show that although most staff recognise that their field courses help students to develop transferable skills, staff awareness of skills and professional development outcomes is narrowly focused on technical skills and discipline-related careers. Furthermore, those transferable skills outcomes that staff are aware of are not fully translated into module specifications and infrequently signposted to students via teaching materials. These findings suggest that transferable skills form a hidden curriculum of fieldwork. To maximise the employability benefits of fieldwork, we recommend that all skills should be signposted to students both during field course teaching and also via the associated teaching materials
E. coli O157 on Scottish cattle farms: evidence of local spread and persistence using repeat cross-sectional data
<b>Background</b><p></p>
Escherichia coli (E. coli) O157 is a virulent zoonotic strain of enterohaemorrhagic E. coli. In Scotland (1998-2008) the annual reported rate of human infection is 4.4 per 100,000 population which is consistently higher than other regions of the UK and abroad. Cattle are the primary reservoir. Thus understanding infection dynamics in cattle is paramount to reducing human infections.<p></p>
A large database was created for farms sampled in two cross-sectional surveys carried out in Scotland (1998 - 2004). A statistical model was generated to identify risk factors for the presence of E. coli O157 on farms. Specific hypotheses were tested regarding the presence of E. coli O157 on local farms and the farms previous status. Pulsed-field gel electrophoresis (PFGE) profiles were further examined to ascertain whether local spread or persistence of strains could be inferred.<p></p>
<b>Results</b><p></p>
The presence of an E. coli O157 positive local farm (average distance: 5.96km) in the Highlands, North East and South West, farm size and the number of cattle moved onto the farm 8 weeks prior to sampling were significant risk factors for the presence of E. coli O157 on farms. Previous status of a farm was not a significant predictor of current status (p = 0.398). Farms within the same sampling cluster were significantly more likely to be the same PFGE type (p < 0.001), implicating spread of strains between local farms. Isolates with identical PFGE types were observed to persist across the two surveys, including 3 that were identified on the same farm, suggesting an environmental reservoir. PFGE types that were persistent were more likely to have been observed in human clinical infections in Scotland (p < 0.001) from the same time frame.<p></p>
<b>Conclusions</b><p></p>
The results of this study demonstrate the spread of E. coli O157 between local farms and highlight the potential link between persistent cattle strains and human clinical infections in Scotland. This novel insight into the epidemiology of Scottish E. coli O157 paves the way for future research into the mechanisms of transmission which should help with the design of control measures to reduce E. coli O157 from livestock-related sources
An Antithrombin-Heparin Complex Increases the Anticoagulant Activity of Fibrin Clots
Clotting blood contains fibrin-bound thrombin, which is a major source of procoagulant activity leading to clot extension and further activation of coagulation. When bound to fibrin, thrombin is protected from inhibition by antithrombin (AT) + heparin but is neutralized when AT and heparin are covalently linked (ATH). Here, we report the surprising observation that, rather than yielding an inert complex, thrombin-ATH formation converts clots into anticoagulant surfaces that effectively catalyze inhibition of thrombin in the surrounding environment
Gill's model of the Antarctic Circumpolar Current, revisited: the role of latitudinal variations in wind stress
Adrian Gillâs (1968) model of the Antarctic Circumpolar Current (ACC) is reinterpreted for a stratified, reduced-gravity ocean, where the barotropic streamfunction is replaced by the pycnocline depth, and the bottom drag coefficient by the Gent and McWilliams eddy diffusivity. The resultant model gives a simple description of the lateral structure of the ACC that is consistent with contemporary descriptions of ACC dynamics. The model is used to investigate and interpret the sensitivity of the ACC to the latitudinal profile of the surface wind stress. A substantial ACC remains when the wind jet is shifted north of the model Drake Passage, even by several thousand kilometers. The integral of the wind stress over the circumpolar streamlines is found to be a useful predictor of the magnitude of the volume transport through the model Drake Passage, although it is necessary to correct for basin-wide zonal pressure gradients in order to obtain good quantitative agreement
Identification of novel pathways of osimertinib disposition and potential implications for the outcome of lung cancer therapy
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