1,624 research outputs found
Measuring Energetics and Behaviour Using Accelerometry in Cane Toads Bufo marinus
Cane toads Bufo marinus were introduced to Australia as a control agent but now have a rapidly progressing invasion front and damage new habitats they enter. Predictive models that can give expansion rates as functions of energy supply and feeding ground distribution could help to maximise control efficiency but to date no study has measured rates of field energy expenditure in an amphibian. In the present study we used the accelerometry technique to generate behavioural time budgets and, through the derivation of ODBA (overall dynamic body acceleration), to obtain estimates of energetics in free ranging cane toads. This represents the first time that accelerometers have been used to not only quantify the behaviour of animals but also assign to those behaviours rates of energy expenditure. Firstly, laboratory calibrations between ODBA and metabolic rate were obtained and used to generate a common prediction equation for the subject toads (R2â=â0.74). Furthermore, acceleration data recorded during different behaviours was studied to ascertain threshold values for objectively defining behaviour categories. Importantly, while subsequent accelerometer field deployments were relatively short they agreed with previous studies on the proportion of time that cane toads locomote yet suggest that the metabolic rate of cane toads in the wild may sometimes be considerably higher than might be assumed based on data for other species
A different angle: comparative analyses of whole-animal transport costs running uphill
Comparative work on animals' costs of terrestrial locomotion has focussed on the underpinning physiology and biomechanics. Often, much of an animal's energy budget is spent on moving around thus there is also value in interpreting such data from an ecological perspective. When animals move through their environment they encounter topographical variation, and this is a key factor that can dramatically affect their energy expenditure. We collated published data on the costs for birds and mammals to locomote terrestrially on inclines, and investigated the scaling relationships using a phylogenetically informed approach. We show that smaller animals have a greater mass-specific cost of transport on inclines across the body mass range analysed. We also demonstrate that the increase in cost for smaller animals to run up a slope relative to along a flat surface is comparatively low. Heavier animals show larger absolute and relative increases in energy cost to travel uphill. Consideration of all aspects of the cost of incline locomotion â absolute, relative, and mass-specific â provides a fuller understanding of the interactions between transport costs, body mass, incline gradient and phylogeny, and enables us to consider their ecological implications, which we couch within the context of the âenergy landscapeâ.</jats:p
The road less traveled: transport of Legionella to the endoplasmic reticulum
Phagosomes containing the bacterial pathogen Legionella pneumophila are transported to the ER after macrophage internalization. To modulate phagosome transport, Legionella use a specialized secretion system that injects bacterial proteins into eukaryotic cells. This review will focus on recent studies that have identified bacterial proteins and host processes that play a concerted role in transporting Legionella to the ER
Poly(2-propylacrylic acid)/poly(lactic-co-glycolic acid) blend microparticles as a targeted antigen delivery system to direct either CD4+ or CD8+ T cell activation.
Poly(lactic-co-glycolic acid) (PLGA) based microparticles (MPs) are widely investigated for their ability to load a range of molecules with high efficiency, including antigenic proteins, and release them in a controlled manner. Micron-sized PLGA MPs are readily phagocytosed by antigen presenting cells, and localized to endosomes. Due to low pH and digestive enzymes, encapsulated protein cargo is largely degraded and processed in endosomes for MHC-II loading and presentation to CD4+ T cells, with very little antigen delivered into the cytosol, limiting MHC-I antigenic loading and presentation to CD8+ T cells. In this work, PLGA was blended with poly(2-propylacrylic acid) (PPAA), a membrane destabilizing polymer, in order to incorporate an endosomal escape strategy into PLGA MPs as an easily fabricated platform with diverse loading capabilities, as a means to enable antigen presentation to CD8+ T cells. Ovalbumin (OVA)-loaded MPs were fabricated using a water-in-oil double emulsion with a 0% (PLGA only), 3 and 10% PPAA composition. MPs were subsequently determined to have an average diameter of 1 Âľm, with high loading and a release profile characteristic of PLGA. Bone marrow derived dendritic cells (DCs) were then incubated with MPs in order to evaluate localization, processing, and presentation of ovalbumin. Endosomal escape of OVA was observed only in DC groups treated with PPAA/PLGA blends, which promoted high levels of activation of CD8+ OVA-specific OT-I T cells, compared to DCs treated with OVA-loaded PLGA MPs which were unable activate CD8+ T cells. In contrast, DCs treated with OVA-loaded PLGA MPs promoted OVA-specific OT-II CD4+ T cell activation, whereas PPAA incorporation into the MP blend did not permit CD4+ T cell activation. These studies demonstrate PLGA MP blends containing PPAA are able to provide an endosomal escape strategy for encapsulated protein antigen, enabling the targeted delivery of antigen for tunable presentation and activation of either CD4+ or CD8+ T cells
Genetic associations of novel behaviour traits derived from social network analysis with growth, feed efficiency, and carcass characteristics in pigs
Reducing harmful aggressive behaviour remains a major challenge in pig production. Social network analysis (SNA) showed the potential in providing novel behavioural traits that describe the direct and indirect role of individual pigs in pen-level aggression. Our objectives were to (1) estimate the genetic parameters of these SNA traits, and (2) quantify the genetic associations between the SNA traits and commonly used performance measures: growth, feed intake, feed efficiency, and carcass traits. The animals were video recorded for 24 h post-mixing. The observed fighting behaviour of each animal was used as input for the SNA. A Bayesian approach was performed to estimate the genetic parameters of SNA traits and their association with the performance traits. The heritability estimates for all SNA traits ranged from 0.01 to 0.35. The genetic correlations between SNA and performance traits were non-significant, except for weighted degree with hot carcass weight, and for both betweenness and closeness centrality with test daily gain, final body weight, and hot carcass weight. Our results suggest that SNA traits are amenable for selective breeding. Integrating these traits with other behaviour and performance traits may potentially help in building up future strategies for simultaneously improving welfare and performance in commercial pig farms
Genetic associations between human-directed behavior and intraspecific social aggression in growing pigs
Genetic associations between human-directed behavior and intraspecific social aggression in growing pigs
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Integrated motivational interviewing and cognitive behavioural therapy for people with psychosis and comorbid substance misuse: randomised controlled trial
Objectives
To evaluate the effectiveness of integrated motivational interviewing and cognitive behaviour therapy in addition to standard care for patients with psychosis and a co-morbid substance use problem.
Design
Two-centre, open, rater-blind randomised controlled trial
Setting
UK Secondary Care
Participants
327 patients with clinical diagnoses of schizophrenia, schizophreniform or schizoaffective disorder and DSM-IV diagnoses of drug and/or alcohol dependence or abuse
Interventions
Participants were randomly allocated to integrated motivational interviewing and cognitive behaviour therapy or standard care. Therapy has two phases. Phase one â âmotivation buildingâ â concerns engaging the patient, then exploring and resolving ambivalence for change in substance use. Phase two ââActionâ â supports and facilitates change using cognitive behavioural approaches. Up to 26 therapy sessions were delivered over one year.
Main outcomes
The primary outcome was death from any cause or admission to hospital in the 12 months after therapy. Secondary outcomes were frequency and amount of substance use (Timeline Followback), readiness to change, perceived negative consequences of use, psychotic symptom ratings, number and duration of relapses, global assessment of functioning and deliberate self harm, at 12 and 24 months, with additional Timeline Followback assessments at 6 and 18 months. Analysis was by intention-to-treat with robust treatment effect estimates.
Results
327 participants were randomised. 326 (99.7%) were assessed on the primary outcome, 246 (75.2%) on main secondary outcomes at 24 months. Regarding the primary outcome, there was no beneficial treatment effect on hospital admissions/ death during follow-up, with 20.2% (33/163) of controls and 23.3% (38/163) of the therapy group deceased or admitted (adjusted odds-ratio 1.16; P= 0.579; 95% confidence interval 0.68 to 1.99). For secondary outcomes there was no treatment effect on frequency of substance use or perceived negative consequences, but a statistically significant effect of therapy on amount used per substance-using day (adjusted odds-ratios: (a) for main substance 1.50; P=0.016; 1.08 to 2.09, (b) all substances 1.48; P=0.017; 1.07 to 2.05). There was a statistically significant treatment effect on readiness to change use at 12 months (adjusted odds-ratio 2.05; P=0.004; 1.26 to 3.31), not maintained at 24 months. There were no treatment effects on assessed clinical outcomes.
Conclusions
Integrated motivational interviewing and cognitive behaviour therapy for people with psychosis and substance misuse does not improve outcome in terms of hospitalisation, symptom outcomes or functioning. It does result in a reduction in amount of substance use which is maintained over the yearâs follow up.
Trial registration
Current Controlled Trials: ISRCTN1440448
SN 2006bp: Probing the Shock Breakout of a Type II-P Supernova
HET optical spectroscopy and unfiltered ROTSE-III photometry spanning the
first 11 months since explosion of the Type II-P SN 2006bp are presented. Flux
limits from the days before discovery combined with the initial rapid
brightening suggest the supernova was first detected just hours after shock
breakout. Optical spectra obtained about 2 days after breakout exhibit narrow
emission lines corresponding to HeII 4200, HeII 4686, and CIV 5805 in the rest
frame, and these features persist in a second observation obtained 5 hours
later; however, these emission lines are not detected the following night nor
in subsequent observations. We suggest that these lines emanate from material
close to the explosion site, possibly in the outer layers of the progenitor
that have been ionized by the high energy photons released at shock breakout. A
P-Cygni profile is observed around 4450 A in the +2 and +3 day spectra.
Previous studies have attributed this feature to high velocity H-beta, but we
discuss the possibility that this profile is instead due to HeII 4687. Further
HET observations (14 nights in total) covering the spectral evolution across
the photometric plateau up to 73 days after breakout and during the nebular
phase around day +340 are presented, and expansion velocities are derived for
key features. The measured decay slope for the unfiltered light curve is 0.0073
+/- 0.0004 mag/day between days +121 and +335, which is significantly slower
than the decay of rate 56Co. We combine our HET measurements with published
X-ray, UV, and optical data to obtain a quasi-bolometric light curve through
day +60. We see a slow cooling over the first 25 days, but no sign of an early
sharp peak; any such feature from the shock breakout must have lasted less than
~1 day.[ABRIDGED]Comment: ApJ accepted, 43 page
The Ursinus Weekly, March 15, 1965
Sig Nu and inactive Demas win Sorority-Fraternity Song Fest ⢠Roving reporter ⢠The grammarian\u27s funeral, or Easy does it ⢠Silent generation whispers, non-quiet editor speaks ⢠Upper classmen reveal soph shingles technique ⢠Editorial: Come on, girls! ⢠A view of fraternity bids ⢠Letter to the editor ⢠Admissions Office, Spring 1960 ⢠Campus song: Addendum ⢠Advice column ⢠To a seminar in Spring ⢠Greek gleaningshttps://digitalcommons.ursinus.edu/weekly/1243/thumbnail.jp
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