292 results on '"MADDISON, A."'
Search Results
2. Generation of Oviductal Glycoprotein 1 Cre Mouse Model for the Study of Secretory Epithelial Cells of the Oviduct.
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McGlade, Emily A, Mao, Jiude, Stephens, Kalli K, Kelleher, Andrew M, Maddison, Lisette A, Bernhardt, Miranda L, DeMayo, Francesco J, Lydon, John P, and Winuthayanon, Wipawee
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EPITHELIAL cells ,OVIDUCT ,LABORATORY mice ,GREEN fluorescent protein ,ANIMAL disease models - Abstract
The epithelial cell lining of the oviduct plays an important role in oocyte pickup, sperm migration, preimplantation embryo development, and embryo transport. The oviduct epithelial cell layer comprises ciliated and nonciliated secretory cells. The ciliary function has been shown to support gamete and embryo movement in the oviduct, yet secretory cell function has not been well characterized. Therefore, our goal was to generate a secretory cell-specific Cre recombinase mouse model to study the role of the oviductal secretory cells. A knock-in mouse model, Ovgp1
Cre:eGFP , was created by expressing Cre from the endogenous Ovgp1 (oviductal glycoprotein 1) locus, with enhanced green fluorescent protein (eGFP) as a reporter. EGFP signals were strongly detected in the secretory epithelial cells of the oviducts at estrus in adult Ovgp1Cre:eGFP mice. Signals were also detected in the ovarian stroma, uterine stroma, vaginal epithelial cells, epididymal epithelial cells, and elongated spermatids. To validate recombinase activity, progesterone receptor (PGR) expression was ablated using the Ovgp1Cre:eGFP ; Pgrf/f mouse model. Surprisingly, the deletion was restricted to the epithelial cells of the uterotubal junction (UTJ) region of Ovgp1Cre:eGFP ; Pgrf/f oviducts. Deletion of Pgr in the epithelial cells of the UTJ region had no effect on female fecundity. In summary, we found that eGFP signals were likely specific to secretory epithelial cells in all regions of the oviduct. However, due to a potential target-specific Cre activity, validation of appropriate recombination and expression of the gene(s) of interest is absolutely required to confirm efficient deletion when generating conditional knockout mice using the Ovgp1Cre:eGFP line. [ABSTRACT FROM AUTHOR]- Published
- 2024
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3. Circadian photoentrainment varies by season and depressed state: associations between light sensitivity and sleep and circadian timing.
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Wescott, Delainey L, Hasler, Brant P, Franzen, Peter L, Taylor, Maddison L, Klevens, Alison M, Gamlin, Paul, Siegle, Greg J, and Roecklein, Kathryn A
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- 2024
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4. Predictors of mortality shortly after entering a long-term care facility.
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Jorissen, Robert N, Wesselingh, Steve L, Whitehead, Craig, Maddison, John, Forward, John, Bourke, Alice, Harvey, Gillian, Crotty, Maria, Collaborators, STAAR-SA Study, and Inacio, Maria C
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MORTALITY risk factors ,RISK assessment ,PREDICTION models ,AUSTRALIANS ,RESEARCH funding ,HEALTH status indicators ,LONG-term health care ,SEX distribution ,RETROSPECTIVE studies ,DESCRIPTIVE statistics ,LONGITUDINAL method ,NURSING care facilities ,CONFIDENCE intervals ,DRUGS ,PROPORTIONAL hazards models ,ACTIVITIES of daily living - Abstract
Objective Moving into a long-term care facility (LTCF) requires substantial personal, societal and financial investment. Identifying those at high risk of short-term mortality after LTCF entry can help with care planning and risk factor management. This study aimed to: (i) examine individual-, facility-, medication-, system- and healthcare-related predictors for 90-day mortality at entry into an LTCF and (ii) create risk profiles for this outcome. Design Retrospective cohort study using data from the Registry of Senior Australians. Subjects Individuals aged ≥ 65 years old with first-time permanent entry into an LTCF in three Australian states between 01 January 2013 and 31 December 2016. Methods A prediction model for 90-day mortality was developed using Cox regression with the purposeful variable selection approach. Individual-, medication-, system- and healthcare-related factors known at entry into an LTCF were examined as predictors. Harrell's C-index assessed the predictive ability of our risk models. Results 116,192 individuals who entered 1,967 facilities, of which 9.4% (N = 10,910) died within 90 days, were studied. We identified 51 predictors of mortality, five of which were effect modifiers. The strongest predictors included activities of daily living category (hazard ratio [HR] = 5.41, 95% confidence interval [CI] = 4.99–5.88 for high vs low), high level of complex health conditions (HR = 1.67, 95% CI = 1.58–1.77 for high vs low), several medication classes and male sex (HR = 1.59, 95% CI = 1.53–1.65). The model out-of-sample Harrell's C-index was 0.773. Conclusions Our mortality prediction model, which includes several strongly associated factors, can moderately well identify individuals at high risk of mortality upon LTCF entry. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Lower jaw modularity in the African clawed frog (Xenopus laevis) and fire salamander (Salamandra salamandra gigliolii).
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Stevens, Maddison, Fabre, Anne-Claire, and Felice, Ryan N
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XENOPUS , *XENOPUS laevis , *SALAMANDERS , *GENETIC correlations , *SKULL , *AMPHIBIANS - Abstract
Modularity describes the degree to which the components of complex phenotypes vary semi-autonomously due to developmental, genetic and functional correlations. This is a key feature underlying the potential for evolvability, as it can allow individual components to respond to different selective pressures semi-independently. The vertebrate lower jaw has become a model anatomical system for understanding modularity, but to date most of this work has focused on the mandible of mammals and other amniotes. In contrast, modularity in the mandible of lissamphibians has been less well studied. Here, we used geometric morphometrics to quantify the static (intraspecific) modularity patterns in Xenopus laevis and Salamandra salamandra gigliolii. We tested developmental and functional hypotheses of modularity and demonstrate that both species exhibit significant modularity. Functional modularity was supported in both Xenopus and Salamandra. Allometry has a small yet significant impact on lower jaw shape in both taxa and sex has a significant effect on shape in Xenopus. The high lower jaw modularity in both species observed here, combined with the well-established modularity of the amphibian cranium, suggests that modularity is a ubiquitous feature of the tetrapod head. [ABSTRACT FROM AUTHOR]
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- 2024
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6. The interrelationships between sleep regularity, obstructive sleep apnea, and hypertension in a middle-aged community population.
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Sansom, Kelly, Reynolds, Amy, Windred, Daniel, Phillips, Andrew, Dhaliwal, Satvinder S, Walsh, Jennifer, Maddison, Kathleen, Singh, Bhajan, Eastwood, Peter, and McArdle, Nigel
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- 2024
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7. Getting the epidemiological associations of physical inactivity with diseases and injuries correct in comparative risk assessment.
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Bourke, Emily, Maddison, Ralph, and Blakely, Tony
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SEDENTARY behavior , *RISK assessment , *PHYSICAL activity , *WOUNDS & injuries , *BODY weight - Abstract
Physical inactivity is associated with a range of health benefits, but current estimates of its impact on disease burden are underestimated. This article explores the limitations of current models used to assess the health loss due to physical inactivity and argues for a more sophisticated approach. The article highlights missing direct pathways, such as the protective effect of physical activity on depression and anxiety, as well as missing indirect effects, such as the impact of physical inactivity on diabetes and other diseases. The article also suggests considering the potential role of body weight and factoring in the health loss due to injuries incurred while gaining physical activity. Improving these estimates will provide better insights into the burden of physical inactivity and improve public health and economic modeling. [Extracted from the article]
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- 2023
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8. Sexual health in a new cultural context: a resource for international students in regional Australia.
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MacPhail, Catherine and Stratten, Maddison
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RESEARCH , *RESEARCH methodology , *CULTURAL pluralism , *INTERVIEWING , *EXPERIENCE , *QUALITATIVE research , *INFORMATION resources , *RESEARCH funding , *DESCRIPTIVE statistics , *THEMATIC analysis , *DATA analysis software , *SEXUAL health - Abstract
A large number of international students enrol in Australian higher education and contribute to Australia's multicultural population. Diverse cultural backgrounds and life experiences impact international students' knowledge of sexual health and healthy relationships. Along with unfamiliarity of the Australian healthcare system, this may place international students at risk of poor sexual health. We explored the sexual health priorities of international students with 12 male and 16 female international students aged between 18 and 49 years, for the development of a sexual health and relationship information resource for international students. Interviews were recorded, transcribed verbatim and coded thematically in Nvivo 12. Students noted that cultural norms about sex inhibited their ability to access information and they had concerns about their relationship behaviours within the Australian cultural context. Some participants noted challenges with accessing information and care and were enthusiastic about increasing international student access to reliable information and access to services. Based on the findings from these interviews, we developed a resource specifically for international students and evaluated its design and content through three focus group discussions with international students. This evaluation data informed refinements made to the resource. The resource Kit contains sexual health and relationship information and provides links to reputable online sexual health information. The Kit has been widely distributed to international students and is currently being further evaluated for use and acceptability. [ABSTRACT FROM AUTHOR]
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- 2023
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9. Syntheses of guanidinoacetate and creatine in maternal tissues and placentae of gestating gilts fed diets with or without supplemental creatine.
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Connolly, Erin D., Wenliang He, Lopez, Arianna, Olivarez, Maddison, Cain, Joseph, Lefevre, Carli, Ross, Alex, Johnson, Gregory, Bazer, Fuller, and Guoyao Wu
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DIETARY supplements ,CREATINE ,SOWS ,FETAL development ,AMINO acids ,ESTRUS - Abstract
This study determined the effects of dietary supplementation with creatine to gestating gilts (n = 6) on their ability to form guanidinoacetate (GA) and creatine in placentae and maternal tissues. Gilts were assigned randomly to one of two dietary groups: control and creatine supplementation (Cr; n = 12 gilts/ diet). Once estrus was detected (d 0), gilts were artificially inseminated 12 h and 24 h later. All gilts were individually housed and fed 0.9 kg of a corn- and soybean-based diet containing 14% crude protein (but no creatine or GA) twice daily. Gilts in the control and Cr groups received daily top dressing of 0 or 2 × 15 g Cr either between d 10 and 60 or between d 10 and 90 of gestation. There were 6 gilts per dietary treatment per gestational stage. On either d 60 or 90 of gestation, gilts were euthanized to collect maternal tissues and placentae. Each tissue (~150 mg) was incubated at 37 ℃ for 2 h in 2 mL of oxygenated (95% O
2 /5% CO2 ) Krebs bicarbonate buffer with or without a) 2 mM glycine plus 2 mM L-arginine or b) 0.2 mM GA plus 0.5 mM L-methionine (the source of S-adenosylmethionine). After the 2-h period of incubation, 0.2 mL of 1.5 M HClO4 was added to the medium. The acidified medium plus tissue was homogenized and the homogenizer rinsed with 1 mL water, followed by the addition of 0.1 mLl of 2 M K2 CO3 . The extract was analyzed for GA, creatine, and amino acids using HPLC. Results indicated that on both d 60 and 90 of gestation, a) GA was formed from glycine plus L-arginine by maternal kidneys and pancreas of all gilts, but not maternal liver, placentae, or endometria; b) GA was converted into Cr by both maternal liver and pancreas, but not maternal kidneys, endometria, or placentae; c) dietary supplementation with Cr did not affect (P > 0.05) either the formation of GA from glycine plus L-arginine in maternal kidneys and pancreas or the conversion of GA into creatine in maternal liver and pancreas (Tables 1 and 2). Collectively, these results indicate interorgan cooperation to form creatine in pregnant gilts to support fetal growth and development, as well as the lack of inhibition of this metabolic pathway by dietary supplementation with creatine. [ABSTRACT FROM AUTHOR]- Published
- 2024
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10. Synthesis of glycine from trans-4-hydroxy- L-proline by placentae but not endometria of gestating gilts.
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Connolly, Erin D., Wenliang He, Lopez, Arianna, Olivarez, Maddison, Cain, Joseph, Lefevre, Carli, Ross, Alex, Johnson, Gregory, Bazer, Fuller, and Guoyao Wu
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AMINO acids ,SOYBEAN as feed ,SOWS ,SERINE ,PLACENTA - Abstract
4-hydroxy-L-proline (Hyp) is an abundant amino acid in the collagen of pigs. The turnover of this protein releases a large amount of Hyp, traditionally considered a metabolic waste. However, results of recent studies documented the conversion of Hyp into glycine in young pigs. Because pregnant gilts are typically fed a soybean meal-based diet that contains insufficient glycine and provides only 35% of the total glycine needed by pregnant gilts, it is possible that the conceptus can form glycine from Hyp. This hypothesis was tested in the present study. Gilts were fed a 1.8-kg corn- and soybean meal-based diet containing 14% crude protein. On d 90 of gestation, gilts (n = 5) were hysterectomized after euthanasia. Slices (~ 100 mg) of placentae or endometria were incubated at 37 °C for 2 h in oxygenated (95% O
2 /5% CO2 ) Krebs-Henseleit bicarbonate buffer (pH 7.4, with 5 mM D-glucose) containing 0 or 2 mM Hyp. After a period of 2 h incubation, 200 μL of 1.5 M HClO4 was added into the incubation medium to stop the reaction. The tissues were homogenized and rinsed with 1 mL water, followed by the addition of 100 μL of 2 M K²CO³. The neutralized extract was analyzed for amino acids using HPLC involving derivatization with o-phthaldialdehyde. Tissues that received no incubation time were determined as well. Data were analyzed by the paired t-test. Results indicated that glycine was produced from 2 mM Hyp by the placenta (Table 1). Glycine was subsequently converted into serine by the placenta. The formation of glycine and serine from Hyp was not due to protein breakdown because there were no differences (P > 0.05) in concentrations of tyrosine (an amino acid that is neither synthesized nor degraded by porcine placentae) in the incubation medium plus tissue at the end of a 2-h incubation period. In contrast to placentae, endometria did not form glycine or serine from Hyp. These findings indicate an important role for Hyp in the provision of both glycine and serine in the conceptus, which may be nutritionally and physiologically significant to compensate for a deficiency of glycine in maternal diets for gestating gilts. (Supported by a USDA/NIFA grant # 2022-67015-36376 and USDA multistate Hatch project #7752: S1081) [ABSTRACT FROM AUTHOR]- Published
- 2024
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11. Estimating sleep duration: performance of open-source processing of actigraphy compared to in-laboratory polysomnography in the community.
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Sansom, Kelly, Reynolds, Amy, McVeigh, Joanne, Mazzotti, Diego R, Dhaliwal, Satvinder S, Maddison, Kathleen, Walsh, Jennifer, Singh, Bhajan, Eastwood, Peter, and McArdle, Nigel
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ACTIGRAPHY ,POLYSOMNOGRAPHY ,REGRESSION analysis ,SLEEP duration ,ACCELEROMETRY ,COMPARATIVE studies ,T-test (Statistics) ,PEARSON correlation (Statistics) ,DESCRIPTIVE statistics ,QUESTIONNAIRES ,SOCIAL classes ,RESEARCH funding ,DATA analysis software - Abstract
Comparisons of actigraphy findings between studies are challenging given differences between brand-specific algorithms. This issue may be minimized by using open-source algorithms. However, the accuracy of actigraphy-derived sleep parameters processed in open-source software needs to be assessed against polysomnography (PSG). Middle-aged adults from the Raine Study (n = 835; F 58%; Age 56.7 ± 5.6 years) completed one night of in-laboratory PSG and concurrent actigraphy (GT3X+ ActiGraph). Actigraphic measures of total sleep time (TST) were analyzed and processed using the open-source R-package GENEActiv and GENEA data in R (GGIR) with and without a sleep diary and additionally processed using proprietary software, ActiLife, for comparison. Bias and agreement (intraclass correlation coefficient) between actigraphy and PSG were examined. Common PSG and sleep health variables associated with the discrepancy between actigraphy, and PSG TST were examined using linear regression. Actigraphy, assessed in GGIR, with and without a sleep diary overestimated PSG TST by (mean ± SD) 31.0 ± 50.0 and 26.4 ± 69.0 minutes, respectively. This overestimation was greater (46.8 ± 50.4 minutes) when actigraphy was analyzed in ActiLife. Agreement between actigraphy and PSG TST was poor (ICC = 0.27–0.44) across all three methods of actigraphy analysis. Longer sleep onset latency and longer wakefulness after sleep onset were associated with overestimation of PSG TST. Open-source processing of actigraphy in a middle-aged community population, agreed poorly with PSG and, on average, overestimated TST. TST overestimation increased with increasing wakefulness overnight. Processing of actigraphy without a diary in GGIR was comparable to when a sleep diary was used and comparable to actigraphy processed with proprietary algorithms in ActiLife. [ABSTRACT FROM AUTHOR]
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- 2023
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12. Now you see it! Using wearable cameras to gain insights into the lived experience of cardiovascular conditions.
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Nourse, Rebecca, Cartledge, Susie, Tegegne, Teketo, Gurrin, Cathal, and Maddison, Ralph
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CARDIOVASCULAR disease prevention ,PRIVACY ,DIGITAL image processing ,SELF-management (Psychology) ,WEARABLE technology ,ACTIVITIES of daily living ,EXPERIENCE ,CONTENT mining ,HUMAN services programs ,PHOTOGRAPHY ,COST analysis ,AUTOMATION ,MEDICAL ethics ,MEDICAL research ,HEART failure ,NURSING interventions - Abstract
Wearable cameras offer an innovative way to discover new insights into the lived experience of people with cardiovascular conditions. Wearable cameras can be used alone or supplement more traditional research methods, such as interviews and participant observations. This paper provides an overview of the benefits of using wearable cameras for data collection and outlines some key considerations for researchers and clinicians interested in this method. We provide a case study describing a study design using wearable cameras and how the data were used. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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13. Continuous positive airway pressure and adverse cardiovascular events in obstructive sleep apnea: are participants of randomized trials representative of sleep clinic patients?
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Reynor, Ayesha, McArdle, Nigel, Shenoy, Bindiya, Dhaliwal, Satvinder S, Rea, Siobhan C, Walsh, Jennifer, Eastwood, Peter R, Maddison, Kathleen, Hillman, David R, Ling, Ivan, Keenan, Brendan T, Maislin, Greg, Magalang, Ulysses, Pack, Allan I, Mazzotti, Diego R, Lee, Chi-Hang, and Singh, Bhajan
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- 2022
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14. health and wellbeing programme for preadolescents in underserved Australian communities: child and stakeholder perspectives.
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Norman, Jennifer, Weerdenburg, Katherine van, Furber, Susan, Stratten, Maddison, and Okely, Anthony D
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WELL-being ,RESEARCH methodology ,STAKEHOLDER analysis ,INTERVIEWING ,SOUND recordings - Abstract
Social inequities in childhood affect children's health and development. Active In-Betweens is a weekly, healthy lifestyle and outdoor activity after-school programme, tailor-made for preadolescent children (9–12 year olds), incorporating a strengths-based, trauma-informed, co-designed and place-based approach. This study evaluated the extent to which the programme strategies and activities met the anticipated short- to medium-term programme outcomes during its first year of operation in two socio-economically disadvantaged housing communities in New South Wales, Australia. A qualitative case study used data from semi-structured interviews with child participants (n = 11) and key stakeholders (n = 10). A broad range of positive outcomes were described. Children's feedback indicated they had experienced opportunities which facilitated the development of new physical activity skills; new healthy eating experiences and knowledge; positive relationships with peers and facilitators and new connections with neighbourhood programmes and outdoor environments. Stakeholders valued the programme for the positive outcomes they observed among the children and the strong organizational partnerships which resulted. The importance of skilled facilitators to deliver the programme, the engagement of local stakeholders and a long-term commitment to programme delivery, with secure funding to ensure continuity, were clearly identified as integral for effective, sustainable outcomes. [ABSTRACT FROM AUTHOR]
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- 2022
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15. Four new planetesimals around typical and pre-main-sequence stars (PLATYPUS) debris discs at 8.8 mm.
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Norfolk, Brodie J, Maddison, Sarah T, Marshall, Jonathan P, Kennedy, Grant M, Duchêne, Gaspard, Wilner, David J, Pinte, Christophe, Moór, Attila, Matthews, Brenda, Ábrahám, Péter, Kóspál, Ágnes, and van der Marel, Nienke
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PLANETESIMALS , *PARTICLE size distribution , *PLATYPUS , *MECHANICAL properties of condensed matter , *GRAIN size - Abstract
Millimetre continuum observations of debris discs can provide insights into the physical and dynamical properties of the unseen planetesimals that these discs host. The material properties and collisional models of planetesimals leave their signature on the grain size distribution, which can be traced through the millimetre spectral index. We present 8.8 mm observations of the debris discs HD 48370, CPD-72 2713, HD 131488, and HD 32297 using the Australian Telescope Compact Array (ATCA) as part of the PLanetesimals Around TYpical Pre-main-seqUence Stars (PLATYPUS) survey. We detect all four targets with a characteristic beam size of 5 arcsec and derive a grain size distribution parameter that is consistent with collisional cascade models and theoretical predictions for parent planetesimal bodies where binding is dominated by self-gravity. We combine our sample with 19 other millimetre-wavelength-detected debris discs from the literature and calculate a weighted mean grain size power-law index that is close to analytical predictions for a classical steady-state collisional cascade model. We suggest the possibility of two distributions of q in our debris disc sample; a broad distribution (where q ∼ 3.2–3.7) for 'typical' debris discs (gas-poor/non-detection), and a narrow distribution (where q < 3.2) for bright gas-rich discs. Or alternatively, we suggest that there exists an observational bias between the grain size distribution parameter and absolute flux that may be attributed to the detection rates of faint debris discs at |$\rm \sim$| cm wavelengths. [ABSTRACT FROM AUTHOR]
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- 2021
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16. Treating insomnia symptoms with medicinal cannabis: a randomized, crossover trial of the efficacy of a cannabinoid medicine compared with placebo.
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Walsh, Jennifer H, Maddison, Kathleen J, Rankin, Tim, Murray, Kevin, McArdle, Nigel, Ree, Melissa J, Hillman, David R, and Eastwood, Peter R
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- 2021
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17. Measuring Intestinal Permeability When Urine is not an Option.
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Koltes, Dawn A., Wiersema, Maddison, and Kerr, Brian J.
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INTESTINAL physiology , *BIOLOGICAL specimens , *RANDOM effects model , *PERMEABILITY , *INTESTINES , *LACTULOSE - Abstract
The need to understand intestinal health is of increasing importance as the livestock industry seeks to maintain performance efficiency while eliminating prophylactic antibiotic usage. Intestinal permeability is a biomarker of intestinal health as it measures the movement of an indigestible marker across the intestinal barrier with excretion in the urine as the primary biological specimen collected for measurement. The adoption of these methods into poultry has been slow due to the lack of urine excretion. Therefore, the objective of this study is to compare differences in intestinal permeability assays in serum of poultry to determine if these assays could be a reliable method to detect changes in intestinal permeability in poultry under a known stressor. To compare the two commonly used methods [fluorescein isothiocyanate-dextran (FITC-D) method and lactulose/mannitol (LMS) dual sugar method], 2 independent trials were conducted with 40 pens split across 2 fed status (fed or fasted for 12 hours) and 4 sugar treatments (no sugar, FITC-D, LMS, FITC-D+LMS). All pens were sampled at 3 timepoints (14, 28, and 42 days of age) with 5 birds sampled per timepoint. Serum FITC-D was determined through fluorescent spectrophotometry, while mannitol and lactulose concentrations were determined using ion chromatography. Data were analyzed using PROC Glimmix. Fed status, sugar treatment, age, and all 2-and 3-way interactions were included as fixed effects. Trial was included in the model as a random effect with pen included as a repeated effect. Serum lactulose and FITC-D increased in fasted compared with fed birds (P < 0.006). Surprisingly, mannitol, which was expected to be similar across fed and fasted, was increased in fed compared with fasted birds (P < 0.001). The increased concentrations of mannitol in fed birds and measurable concentrations of mannitol in birds not given mannitol suggest another molecule eluted at the same rate as mannitol. Therefore, we propose under these conditions that mannitol, and its ratio with lactulose, are not appropriate methods for measuring intestinal permeability in poultry. Lactulose and FITC-D were increased in serum when the birds were provided those sugars and serum concentration of both sugars decreased at 28 days compared with 14 and 42 days (P < 0.003). FITC-D had a significant 2-way interaction for the sugar by fed status (P < 0.05) whereas other 2-and 3-way interactions were similar across treatments (P > 0.202). Serum lactulose concentrations were affected by all 2-and 3-way interactions with elevated serum lactulose concentrations in broilers provided lactulose and fasted (P < 0.001). Birds that did not receive lactulose had very low to undetectable concentrations of lactulose. This reduced background noise for the detection of serum lactulose and the ability statistically to detect small changes in intestinal permeability make lactulose a potential serum biomarker for intestinal permeability in poultry. [ABSTRACT FROM AUTHOR]
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- 2023
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18. Single-Laboratory Validation of an Immunoaffinity Column Cleanup LC Method for the Analysis of Aflatoxins and Ochratoxin A in Cannabis Plant Material, Resins, Vapes, Isolates, and Edible Products.
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Greaves, Alana, Maddison, Kyle, Doran, Marney, Lin, Sarah, and Geiling, Ben
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OCHRATOXINS , *AFLATOXINS , *EDIBLE coatings , *CANNABIS (Genus) , *PLANT drying , *SALINE solutions , *MYCOSES , *MYCOTOXINS - Abstract
Background: Potential fungal infection of cannabis plants during drying has raised concerns of resulting mycotoxin contamination in leaves and flowers and subsequent contamination of derived products including cannabis-containing edible products. Validated routine methods are essential to monitor cannabis and cannabis products to ensure consumer safety consistent with long-standing controls for mycotoxins such as aflatoxins and ochratoxin A in foodstuffs. Objective: To provide single-laboratory validation data to demonstrate the suitability of a method for determining aflatoxins and ochratoxin A in cannabis plant material, resins, vapes, isolates, and edible products such as chocolate. Method: Extraction of solid and liquid matrixes with acetonitrile:water, centrifugation, and then dilution of an aliquot of supernatant with phosphate-buffered saline solution containing Tween 20 surfactant. Cleanup by passing through an immunoaffinity column containing antibodies to both aflatoxins and ochratoxin A and analyzing in a single LC chromatographic run with fluorescence detection. Results: For within-day analysis, recoveries were in the range 77 to 99% with RSDs from 0.7 to 9.6% for aflatoxin B1. Similarly, ochratoxin A recoveries were from 64 to 94% and RSDs from 0.9 to 9.5% for mycotoxin mixtures spiked into cannabis flowers, resins, vapes, isolates, chocolate, gummies, edible oils, and beverages. Conclusions: A method for the determination of aflatoxins and ochratoxin A was successfully developed and singlelaboratory validation data has been presented for cannabis plant material, resins, vapes, isolates, and edible products. Highlights: A multi-mycotoxin immunoaffinity column cleanup with LC-fluorescence has been validated and shown to be suitable for routine control of aflatoxins and ochratoxin A in cannabis flowers and a diverse range of edible cannabis products. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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19. Dust traps and the formation of cavities in transition discs: a millimetre to sub-millimetre comparison survey.
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Norfolk, Brodie J, Maddison, Sarah T, Pinte, Christophe, van der Marel, Nienke, Booth, Richard A, Francis, Logan, Gonzalez, Jean-François, Ménard, François, Wright, Chris M, van der Plas, Gerrit, and Garg, Himanshi
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DUST , *TELESCOPES - Abstract
The origin of the inner dust cavities observed in transition discs remains unknown. The segregation of dust and size of the cavity is expected to vary depending on which clearing mechanism dominates grain evolution. We present the results from the Discs Down Under program, an 8.8-mm continuum Australia Telescope Compact Array (ATCA) survey targeting 15 transition discs with large (≳20 au) cavities and compare the resulting dust emission to Atacama Large millimetre/sub-millimetre Array (ALMA) observations. Our ATCA observations resolve the inner cavity for 8 of the 14 detected discs. We fit the visibilities and reconstruct 1D radial brightness models for 10 sources with a S/N > 5 σ. We find that, for sources with a resolved cavity in both wavebands, the 8.8 mm and sub-mm brightness distributions peak at the same radius from the star. We suggest that a similar cavity size for 8.8 mm and sub-mm dust grains is due to a dust trap induced by the presence of a companion. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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20. Barrier-to-autointegration-factor (Banf1) modulates DNA double-strand break repair pathway choice via regulation of DNA-dependent kinase (DNA-PK) activity.
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Burgess, Joshua T, Cheong, Chee Man, Suraweera, Amila, Sobanski, Thais, Beard, Sam, Dave, Keyur, Rose, Maddison, Boucher, Didier, Croft, Laura V, Adams, Mark N, O'Byrne, Kenneth, Richard, Derek J, and Bolderson, Emma
- Published
- 2021
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21. Repetitive DNA Profiles Reveal Evidence of Rapid Genome Evolution and Reflect Species Boundaries in Ground Beetles.
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Sproul, John S, Barton, Lindsey M, and Maddison, David R
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GROUND beetles ,DNA fingerprinting ,RIBOSOMAL DNA ,PHENOMENOLOGICAL biology ,GENOMES ,RECOMBINANT DNA - Abstract
Genome architecture is a complex, multidimensional property of an organism defined by the content and spatial organization of the genome's component parts. Comparative study of entire genome architecture in model organisms is shedding light on mechanisms underlying genome regulation, evolution, and diversification, but such studies require costly analytical approaches which make extensive comparative study impractical for most groups. However, lower-cost methods that measure a single architectural component (e.g. distribution of one class of repeats) have potential as a new data source for evolutionary studies insofar as that measure correlates with more complex biological phenomena, and for which it could serve as part of an explanatory framework. We investigated copy number variation (CNV) profiles in ribosomal DNA (rDNA) as a simple measure reflecting the distribution of rDNA subcomponents across the genome. We find that signatures present in rDNA CNV profiles strongly correlate with species boundaries in the breve species group of Bembidion , and vary across broader taxonomic sampling in Bembidion subgenus Plataphus. Profiles of several species show evidence of re-patterning of rDNA-like sequences throughout the genome, revealing evidence of rapid genome evolution (including among sister pairs) not evident from analysis of traditional data sources such as multigene data sets. Major re-patterning of rDNA-like sequences has occurred frequently within the evolutionary history of Plataphus. We confirm that CNV profiles represent an aspect of genomic architecture (i.e. the linear distribution of rDNA components across the genome) via fluorescence in-situ hybridization. In at least one species, novel rDNA-like elements are spread throughout all chromosomes. We discuss the potential of copy number profiles of rDNA, or other repeats, as a low-cost tool for incorporating signal of genomic architecture variation in studies of species delimitation and genome evolution. [ Bembidion ; Carabidae; copy number variation profiles; rapid genome evolution; ribosomal DNA; species delimitation.] [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
22. High-resolution survey for planetary companions to young stars in the Taurus molecular cloud.
- Author
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Wallace, A L, Kammerer, J, Ireland, M J, Federrath, C, Kraus, A L, Maddison, S T, Rizzuto, A, Birchall, E K, and Martinache, F
- Subjects
MOLECULAR clouds ,PLANETARY mass ,STARS ,PLANETARY systems ,INFRARED imaging ,ADAPTIVE optics ,INTERFERENCE microscopy - Abstract
Direct imaging in the infrared at the diffraction limit of large telescopes is a unique probe of the properties of young planetary systems. We survey 55 single class I and class II stars in Taurus in the L ' filter using natural and laser guide star adaptive optics and the near-infrared camera (NIRC2) of the Keck II telescope, in order to search for planetary-mass companions. We use both reference star differential imaging and kernel phase techniques, achieving typical 5σ contrasts of ∼6 mag at separations of 0.2 arcsec and ∼8 mag beyond 0.5 arcsec. Although, we do not detect any new faint companions, we constrain the frequency of wide separation massive planets, such as HR 8799 analogues. We find that, assuming hot-start models and a planet distribution with power-law mass and semimajor axis indices of −0.5 and −1, respectively, less than 20 per cent of our target stars host planets with masses >2 M
J at separations >10 au. [ABSTRACT FROM AUTHOR]- Published
- 2020
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23. The prevalence of common sleep disorders in young adults: a descriptive population-based study.
- Author
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McArdle, Nigel, Ward, Sarah V, Bucks, Romola S, Maddison, Kathleen, Smith, Anne, Huang, Rae-Chi, Pennell, Craig E, Hillman, David R, and Eastwood, Peter R
- Published
- 2020
- Full Text
- View/download PDF
24. The Resilient Child: Sex-Steroid Hormones and COVID-19 Incidence in Pediatric Patients.
- Author
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Mihalopoulos, Meredith, Levine, Alice C, Marayati, Naoum Fares, Chubak, Barbara M, Archer, Maddison, Badani, Ketan K, Tewari, Ashutosh K, Mohamed, Nihal, Ferrer, Fernando, and Kyprianou, Natasha
- Subjects
PUBERTY ,ANDROGENS ,ESTROGEN ,IMMUNE system ,JUVENILE diseases ,COVID-19 - Abstract
Coronavirus disease–2019 (COVID-19), a disease caused by Severe Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, has become an unprecedented global health emergency, with fatal outcomes among adults of all ages in the United States, and the highest incidence and mortality in adult men. As the pandemic evolves there is limited understanding of a potential association between symptomatic viral infection and age. To date, there is no knowledge of the role children (prepubescent, ages 9-13 years) play as "silent" vectors of the virus, with themselves being asymptomatic. Throughout different time frames and geographic locations, the current evidence on COVID-19 suggests that children are becoming infected at a significantly lower rate than other age groups—as low as 1%. Androgens upregulate the protease TMPRSS2 (type II transmembrane serine protease-2), which facilitates efficient virus-host cell fusion with the epithelium of the lungs, thus increasing susceptibility to SARS-CoV-2 infection and development of severe COVID-19. Owing to low levels of steroid hormones, prepubertal children may have low expression of TMPRSS2, thereby limiting the viral entry into host cells. As the world anticipates a vaccine against SARS-CoV-2, the role of prepubescent children as vectors transmitting the virus must be interrogated to prepare for a potential resurgence of COVID-19. This review discusses the current evidence on the low incidence of COVID-19 in children and the effect of sex-steroid hormones on SARS-CoV-2 viral infection and clinical outcomes of pediatric patients. On reopening society at large, schools will need to implement heightened health protocols with the knowledge that children as the "silent" viral transmitters can significantly affect the adult populations. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
25. Species delimitation, classical taxonomy and genome skimming: a review of the ground beetle genus Lionepha (Coleoptera: Carabidae).
- Author
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Maddison, David R and Sproul, John S
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GROUND beetles , *BEETLES , *NUCLEOTIDE sequencing , *INSECT diversity , *FOSSIL DNA , *CHROMOSOMES - Abstract
The western North American genus Lionepha is shown to contain at least 11 species through a combination of eight-gene species delimitation analyses and morphological study. In order to confirm the names of several species, we sequence DNA of primary types of several names, including a LeConte lectotype collected in the 1850s, using next-generation sequencing. We examine chromosomes of eight species, and show that all have 12 pairs of autosomes and an X0/XX sex-chromosome system. The following species are described as new: Lionepha australerasa , L. kavanaughi , L. lindrothi and L. tuulukwa. The name Lionepha erasa is shown to belong to a relatively rare, western species ranging from Oregon through Alaska; the common, widespread species previously known as Lionepha erasa now takes the name L. probata. Bembidion chintimini , B. lindrothellus and B. lummi are synonymized with L. erasa. We provide tools to identify specimens to species, including illustrations, diagnoses and distribution maps. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
26. Origin and adaptive radiation of the exceptional and threatened bembidiine beetle fauna of St Helena (Coleoptera: Carabidae).
- Author
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Maddison, David R, Sproul, John S, and Mendel, Howard
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GROUND beetles , *BEETLES , *HABITAT destruction , *ANIMALS , *ADAPTIVE radiation - Abstract
The central peaks of the isolated island of St Helena (south Atlantic Ocean) are home to an extraordinary set of ground beetles of the tribe Bembidiini, which belong to three endemic genus-group taxa. These beetles are strikingly different in overall body form from the many bembidiines found elsewhere in the world. At least some of the St Helena species are likely to be extinct, and all are threatened by habitat destruction and invasive species. Through next-generation sequencing of historical museum specimens, we examine the phylogenetic relationships of the St Helena fauna. We find that, in spite of their morphological disparities, the endemic bembidiines of St Helena form a clade of genetically similar species, with their sister group being Bembidion alsium from the Indian Ocean island of La Réunion, and the sister group of this pair being the African subgenus Omotaphus. We propose that the St Helena Peaks Bembidion are an adaptive radiation that arose from a single dispersal event to St Helena from a now-extinct African lineage (sister to Omotaphus) and that this extinct lineage also served as the ancestral source of B. alsium. Given that the St Helena Peaks Bembidion are deeply nested in the genus Bembidion , we move the three taxa back in that genus as subgenera and provide a new name (Bembidion shepherdae) for the now-homonymous Bembidion wollastoni. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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27. Infrared variability due to magnetic pressure-driven jets, dust ejection and quasi-puffed-up inner rims.
- Author
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Liffman, Kurt, Bryan, Geoffrey, Hutchison, Mark, and Maddison, Sarah T
- Subjects
PROTOSTARS ,STELLAR magnetic fields ,JETS (Fluid dynamics) ,DUST ,PARTICLE acceleration ,FLOW velocity ,ACCRETION (Astrophysics) - Abstract
The interaction between a YSO stellar magnetic field and its protostellar disc can result in stellar accretional flows and outflows from the inner disc rim. Gas flows with a velocity component perpendicular to disc mid-plane subject particles to centrifugal acceleration away from the protostar, resulting in particles being catapulted across the face of the disc. The ejected material can produce a 'dust fan', which may be dense enough to mimic the appearance of a 'puffed-up' inner disc rim. We derive analytical equations for the time-dependent disc toroidal field, the disc magnetic twist, the size of the stable toroidal disc region, the jet speed, and the disc region of maximal jet flow speed. We show how the observed infrared variability of the pre-transition disc system LRLL 31 can be modelled by a dust ejecta fan from the inner-most regions of the disc whose height is partially dependent on the jet flow speed. The greater the jet flow speed, the higher is the potential dust fan scale height. An increase in mass accretion on to the star tends to increase the height and optical depth of the dust ejection fan, increasing the amount of 1–8 µm radiation. The subsequent shadow reduces the amount of light falling on the outer disc and decreases the 8–40 µm radiation. A decrease in the accretion rate reverses this scenario, thereby producing the observed 'see-saw' infrared variability. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
28. The fulcrum wavelength of young stellar objects: the case of LRLL 31.
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Bryan, Geoffrey R, Maddison, Sarah T, and Liffman, Kurt
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- *
SPECTRAL energy distribution , *WAVELENGTHS , *RADIATIVE transfer , *DUST explosions - Abstract
A small subset of young stellar objects exhibit 'see-saw' temporal variations in their mid-infrared spectral energy distribution (SED); as the flux shortwards of a fulcrum wavelength (λ f ) increases, the flux longwards of this wavelength decreases (and vice versa) over time-scales of weeks to years. While previous studies have shown that an opaque, axisymmetric occulter of variable height can cause this behaviour in the SED of these objects, the conditions under which a single λ f occurs have not previously been determined, nor the factors determining its value. Using radiative transfer modelling, we conduct a parametric study of the exemplar of this class, LRLL 31 to explore this phenomenon, and confirm that the cause of this flux variation is likely due to the change in height of the optically thick inner rim of the accretion disc at the dust sublimation radius, or some other phenomenon that results in a similar appearance. We also determine that a fulcrum wavelength only occurs for high inclinations, where the line of sight intersects the accretion disc. Accepting that the disc of LRLL 31 is highly inclined, the inner rim radius, radial and vertical density profiles are independently varied to gauge what effect this had on λ f and its position relative to the silicate feature near |$10\, {\mu \rm{m}}$|. While λ f is a function of each of these parameters, it is found to be most strongly dependent on the vertical density exponent β. All other factors being held constant, only for flatter discs (β < 1.2) did we find a λ f beyond the silicate feature. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
29. Characterization of Factors Affecting the Fecal Microbiome in Young Canadian Pigs.
- Author
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McCuaig, Bonita L., Saundh, Stephanie, de Almeida Mesquita, Raiza, McCarthy, E. Luke, Arsenault, Maddison, Prisnee, Tausha, Lillie, Brandon, Farzan, Vahab, Harding, John, Willing, Ben, Links, Matthew, and Van Kessel, Andrew G.
- Subjects
PIGLETS ,SOWS ,SWINE ,ANIMAL weaning ,BACTERIAL communities ,QUALITY control ,BIOMES ,METADATA - Abstract
Although established as an important contributor to pig health and performance, high diversity and variability of the microbiome has challenged identification of a beneficial community composition that could inform best management practice and gut modifier development. To address this challenge, rectal swabs were collected at intervals from near birth to one-week postweaning from 4 piglets in 10 litters from 13 conventional and 9 RWA barns across Canada. The 16S rRNA gene was sequenced in 1,997 fecal samples collected at ~4 days of age (4d), 1 day before weaning (W-1), and 7 days after weaning (W+7), piglets were also weighed at the time of sampling. Raw sequences were denoised and assigned to genera using DADA2. After quality control and filtering there was an average of 32,710 reads per sample, with 649 genera identified in the samples. Principal Coordinate Analysis (PCoA) plots were created using the vegan and phyloseq packages (cao model and MDS settings). Relationships between metadata factors and the microbiome were investigated using PERMANOVA analysis in the adonis2 package. In PCoA plots samples clustered by production stage, with an expected marked change of the bacterial community following weaning. Because production stage had a large effect on the microbiome the effects of metadata factors were investigated within sampling visit. Metadata factors investigated included farrowing pen (FP) location at the 4 d-old sampling, barn and rearing system [conventional versus raised without antibiotics (RWA)] and the lifetime health (LH) status including always healthy, received a health score 1 or greater at any one visit or did not complete the study. At ~4 d of age, PERMANOVA indicated that all these factors were significantly linked to the microbiome composition (P = 0.001), FP explained the most microbiome variation (R2 = 0.338), followed by barn (R2 = 0.217). Rearing system and LH explained much less of the variation, R2 = 0.009 and R2 = 0.005, respectively. At W-1, the microbiome was not significantly correlated to LH (P = 0.053); however, the other metadata factors were significant (P = 0.001) with similar R2 values to the previous timepoint (FP; R2 = 0.317, barn R2 = 0.210, and system R2 = 0.008). At W+7 all metadata factors were once again significant (P < 0.005). The correlation to FP had reduced to R2 = 0.245, cohort increased to R2 = 0.266, system effects doubled to R2 = 0.21, and LH remained very low at R2 = 0.006. However, interactions between LH and FP (R2 = 0.059) and system and LH (R2=0.003) were also observed. These results suggest that farrowing pen has a significant and lasting effect on the microbiome. The effect of being raised RWA or conventionally was very small in preweaning piglets, but that affect increased post weaning. The immediate environment early in life appears to have a large effect on piglet microbiomes and may present an opportunity for beneficial intervention. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
30. Total factor productivity growth in English agriculture: 1690–1914.
- Author
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Maddison, David and Rehdanz, Katrin
- Subjects
INDUSTRIAL productivity ,ECONOMIC history ,GROWTH industries ,AGRICULTURAL economics ,ECONOMIC change ,ECONOMIC models - Abstract
The article describes the importance of state-sponsored extension services and credit and marketing cooperatives. It notes that assessed rents represent the bargain struck between landowner and tenant whereas received rents is the amount actually collected. It adds that the amount of land attributed to particular estates fluctuates because of acquisitions and disposals.
- Published
- 2019
- Full Text
- View/download PDF
31. Tiny grains shining bright in the gaps of Herbig Ae transitional discs.
- Author
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Birchall, Eloise K, Ireland, Michael J, Federrath, Christoph, Monnier, John D, Kraus, Stefan, Willson, Matthew, Kraus, Adam L, Rizzuto, Aaron, Agnew, Matthew T, and Maddison, Sarah T
- Subjects
MARKOV chain Monte Carlo ,TREE-rings ,RADIATIVE transfer ,ADAPTIVE optics - Abstract
This work presents a study of two Herbig Ae transitional discs, Oph IRS 48 and HD 169142; which both have reported rings in their dust density distributions. We use Keck-II/NIRC2 adaptive optics imaging observations in the L′ filter (3.8 |$\mu$| m) to probe the regions of these discs inwards of |${\sim }20\, \mathrm{au}$| from the star. We introduce our method for investigating these transitional discs, which takes a forward modelling approach: making a model of the disc (using the Monte Carlo radiative transfer code radmc3d), convolving it with point spread functions of calibrator stars, and comparing the convolved models with the observational data. The disc surface density parameters are explored with a Monte Carlo Markov Chain technique. Our analysis recovers emission from both of the discs interior to the well-known optically thick walls, modelled as a ring of emission at |${\sim }15\, \mathrm{au}$| in Oph IRS 48, and |${\sim }7\, \mathrm{au}$| for HD 169142, and identifies asymmetries in both discs. Given the brightness of the near-symmetric rings compared to the reported companion candidates, we suggest that the reported companion candidates can be interpreted as slightly asymmetric disc emission or illumination. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
32. Predicting multiple planet stability and habitable zone companions in the TESS era.
- Author
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Agnew, Matthew T, Maddison, Sarah T, Horner, Jonathan, and Kane, Stephen R
- Subjects
- *
HABITABLE planets , *PLANETARY orbits , *PLANETARY systems , *ASTROBIOLOGY , *EXTRASOLAR planets , *COMPUTER simulation - Abstract
We present an approach that is able to both rapidly assess the dynamical stability of multiple planet systems, and determine whether an exoplanet system would be capable of hosting a dynamically stable Earth-mass companion in its habitable zone (HZ). We conduct a suite of numerical simulations using a swarm of massless test particles (TPs) in the vicinity of the orbit of a massive planet, in order to develop a predictive tool which can be used to achieve these desired outcomes. In this work, we outline both the numerical methods we used to develop the tool, and demonstrate its use. We find that the TPs survive in systems either because they are unperturbed due to being so far removed from the massive planet, or due to being trapped in stable mean-motion resonant orbits with the massive planet. The resulting unexcited TP swarm produces a unique signature in (a, e) space that represents the stable regions within the system. We are able to scale and translate this stability signature, and combine several together in order to conservatively assess the dynamical stability of newly discovered multiple planet systems. We also assess the stability of a system's HZ and determine whether an Earth-mass companion could remain on a stable orbit, without the need for exhaustive numerical simulations. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
33. Preoperative Quadriceps Muscle Strength and Functional Ability Predict Performance-Based Outcomes 6 Months After Total Knee Arthroplasty: A Systematic Review.
- Author
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Devasenapathy, Niveditha, Maddison, Ralph, Malhotra, Rajesh, Zodepy, Sanjay, Sharma, Saket, and Belavy, Daniel L
- Subjects
- *
MEDICAL information storage & retrieval systems , *PSYCHOLOGY information storage & retrieval systems , *LIFE skills , *MEDLINE , *MUSCLE strength , *TOTAL knee replacement , *SYSTEMATIC reviews , *QUADRICEPS muscle , *TREATMENT effectiveness , *STAIR climbing , *PREOPERATIVE period , *DATA analysis software , *WALKING speed - Abstract
Background One-third of individuals report limitations in activities of daily living even 6 months after total knee arthroplasty (TKA). Moderate-quality evidence exists for several sociodemographic and clinical predictors of patient-reported outcome measures of perceived functionality. Objectively measured performance-based measures (PBMs) provide a less subjective approach to informing patient treatment after TKA; however, information about predictors of functionally relevant PBMs is scarce. Purpose This systematic review synthesized the available research on preoperative predictors of PBMs after primary TKA for osteoarthritis. Data Sources In June 2016 and January 2017, MEDLINE, EMBASE, and PsycINFO databases were searched. Study Selection Cohort studies exploring preoperative predictors of stair climbing, walking speed, and gait speed measured ≥6 months after primary TKA were included. Screening of abstracts and selection of full texts were undertaken by 2 independent reviewers. Data Extraction Information on study design, patient characteristics, analysis, and results was extracted using pilot-tested forms. Two independent reviewers assessed risk of bias using modified Quality in Prognostic Studies criteria. Data Synthesis Of the eligible 12 studies involving 6 prospective cohorts, 10 studies reported information on baseline predictors. Meta-analysis of predictors was not possible because of missing information on effect size or standard errors. Narrative synthesis of evidence of predictors was therefore performed. Limitations The quality of evidence was low because of the risk of bias and heterogeneity of included studies as well as nonreporting of measures of effect. Conclusions Low-quality evidence exists for an association of preoperative functional ability and quadriceps muscle strength with functionality at 6 months after TKA. Improved reporting of predictor analyses is needed to enable evidence generation for clinical management. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
34. Genome-wide association analysis uncovers variants for reproductive variation across dog breeds and links to domestication.
- Author
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Smith, Samuel P, Phillips, Julie B, Johnson, Maddison L, Abbot, Patrick, Capra, John A, and Rokas, Antonis
- Subjects
PREMATURE labor ,GESTATIONAL age ,DOG breeds ,CESAREAN section ,BODY mass index - Abstract
Background and objectives The diversity of eutherian reproductive strategies has led to variation in many traits, such as number of offspring, age of reproductive maturity and gestation length. While reproductive trait variation has been extensively investigated and is well established in mammals, the genetic loci contributing to this variation remain largely unknown. The domestic dog, Canis lupus familiaris is a powerful model for studies of the genetics of inherited disease due to its unique history of domestication. To gain insight into the genetic basis of reproductive traits across domestic dog breeds, we collected phenotypic data for four traits, cesarean section rate, litter size, stillbirth rate and gestation length, from primary literature and breeders' handbooks. Methodology By matching our phenotypic data to genomic data from the Cornell Veterinary Biobank, we performed genome-wide association analyses for these four reproductive traits, using body mass and kinship among breeds as covariates. Results We identified 12 genome-wide significant associations between these traits and genetic loci, including variants near CACNA2D3 with gestation length, MSRB3 and MSANTD1 with litter size, SMOC2 with cesarean section rate and UFM1 with stillbirth rate. A few of these loci, such as CACNA2D3 and MSRB3 , have been previously implicated in human reproductive pathologies, whereas others have been associated with domestication-related traits, including brachycephaly (SMOC2) and coat curl (KRT71). Conclusions and implications We hypothesize that the artificial selection that gave rise to dog breeds also influenced the observed variation in their reproductive traits. Overall, our work establishes the domestic dog as a system for studying the genetics of reproductive biology and disease. LAY SUMMARY The genetic contributors to variation in mammalian reproductive traits remain largely unknown. We took advantage of the domestic dog, a powerful model system, to test for associations between genome-wide variants and four reproductive traits (cesarean section rate, litter size, stillbirth rate and gestation length) that vary extensively across breeds. We identified associations at a dozen loci, including ones previously associated with domestication-related traits, suggesting that selection on dog breeds also influenced their reproductive traits. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
35. Prospecting for exo-Earths in multiple planet systems with a gas giant.
- Author
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Agnew, Matthew T, Maddison, Sarah T, and Horner, Jonathan
- Subjects
- *
GAS giants , *JUPITER (Planet) , *EXTRASOLAR planets , *ASTRONOMICAL observations , *COMPUTER simulation , *GRAVITATIONAL waves - Abstract
In this work, we hunt for the best places to find exo-Earths in the currently known exoplanet population. While it is still unclear whether Jupiter had a beneficial or detrimental effect on the creation of the right environment for a habitable Earth to develop, we focus on the 51 multiple planet systems that have at least one Jupiter-like planet and aim to identify which would be good candidates to host an exo-Earth. We conduct a series of numerical simulations to identify dynamically stable regions of the habitable zone of the multiple exoplanet systems capable of hosting an Earth-mass planet. We produce a candidate list of 16 systems that could host such a stable exo-Earth in their habitable zone, and for which the induced radial velocity signal of a hypothetical one, two or four Earth-mass planet on the host star would be detectable with the Echelle SPectrograph for Rocky Exoplanet and Stable Spectroscopic Observations spectrograph. We find that whilst the gravitational interactions with the massive planet nearest the habitable zone are critical in determining stability, the secular resonant interactions between multiple planets can also have a dramatic influence on the overall stability of the habitable zone. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
36. Full wavefield inversion of ambient seismic noise.
- Author
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Ridder, S A L de and Maddison, J R
- Subjects
- *
MICROSEISMS , *SEISMOMETERS , *SEISMIC arrays , *PARTIAL differential equations , *PHASE velocity - Abstract
We formulate a full wavefield inversion (FWFI) for ambient seismic noise recorded by large and dense seismograph arrays. FWFI exploits the constraints on the gradients of the wavefield that array data inherently possess. We pose FWFI as a partial differential equation (PDE) constrained inverse problem resulting in a joint estimation of a reconstructed wavefield and the medium parameters. The inverse problem is solved by variable projection. We explicitly allow for non-unique solutions to the PDE system that is imposed as a constraint. The boundary conditions of the wavefield do not need to be specified, and can remain unknown. This makes the algorithm suitable for inverting observations of ambient seismic noise by dense arrays. The result is that the inverse problem for subsurface properties becomes insensitive to the character and distribution of the noise sources that excited the seismic wavefield. In principle the formulation holds equally for ambient noise wavefields and for wavefields excited by controlled sources. The theory is supported with examples in one dimension in the time domain, and in two dimensions in the frequency domain. The latter are of interest in the inversion of surface wave ambient noise for phase velocity maps. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
37. Homeless Cells Escape Death and Deliver Lethal Cancer.
- Author
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Archer, Maddison and Kyprianou, Natasha
- Subjects
CELL death - Published
- 2021
- Full Text
- View/download PDF
38. Distinct HLA associations of LGI1 and CASPR2-antibody diseases.
- Author
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Binks, Sophie, Varley, James, Lee, Wanseon, Makuch, Mateusz, Elliott, Katherine, Gelfand, Jeffrey M, Jacob, Saiju, Leite, M Isabel, Maddison, Paul, Chen, Mian, Geschwind, Michael D, Grant, Eleanor, Sen, Arjune, Waters, Patrick, McCormack, Mark, Cavalleri, Gianpiero L, Barnardo, Martin, Knight, Julian C, and Irani, Sarosh R
- Subjects
ALLELES ,COMPARATIVE studies ,CONFIDENCE intervals ,DRUG side effects ,IMMUNOGLOBULINS ,POTASSIUM ,WHITE people ,HLA-B27 antigen ,MEMBRANE transport proteins ,ODDS ratio - Abstract
The recent biochemical distinction between antibodies against leucine-rich, glioma-inactivated-1 (LGI1), contactin-associated protein-2 (CASPR2) and intracellular epitopes of voltage-gated potassium-channels (VGKCs) demands aetiological explanations. Given established associations between human leucocyte antigen (HLA) alleles and adverse drug reactions, and our clinical observation of frequent adverse drugs reactions in patients with LGI1 antibodies, we compared HLA alleles between healthy controls (n = 5553) and 111 Caucasian patients with VGKC-complex autoantibodies. In patients with LGI1 antibodies (n = 68), HLA-DRB1*07:01 was strongly represented [odds ratio = 27.6 (95% confidence interval 12.9-72.2), P = 4.1 × 10-26]. In contrast, patients with CASPR2 antibodies (n = 31) showed over-representation of HLA-DRB1*11:01 [odds ratio = 9.4 (95% confidence interval 4.6-19.3), P = 5.7 × 10-6]. Other allelic associations for patients with LGI1 antibodies reflected linkage, and significant haplotypic associations included HLA-DRB1*07:01-DQA1*02:01-DQB1*02:02, by comparison to DRB1*11:01-DQA1*05:01-DQB1*03:01 in CASPR2-antibody patients. Conditional analysis in LGI1-antibody patients resolved further independent class I and II associations. By comparison, patients with both LGI1 and CASPR2 antibodies (n = 3) carried yet another complement of HLA variants, and patients with intracellular VGKC antibodies (n = 9) lacked significant HLA associations. Within LGI1- or CASPR2-antibody patients, HLA associations did not correlate with clinical features. In silico predictions identified unique CASPR2- and LGI1-derived peptides potentially presented by the respective over-represented HLA molecules. These highly significant HLA associations dichotomize the underlying immunology in patients with LGI1 or CASPR2 antibodies, and inform T cell specificities and cellular interactions at disease initiation.10.1093/brain/awy109_video1awy109media15796480660001. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
39. Cryptic species in the mountaintops: species delimitation and taxonomy of the Bembidion breve species group (Coleoptera: Carabidae) aided by genomic architecture of a century-old type specimen.
- Author
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SPROUL, JOHN S. and MADDISON, DAVID R.
- Subjects
- *
BEETLES , *GROUND beetles , *SPECIES distribution , *SYMPATRIC speciation , *ANIMAL classification - Abstract
The breve species group includes closely related Bembidion Latreille ground beetles commonly found at high elevation in the mountains of western North America. For several decades, the group has been considered to consist of two species. Here, we present evidence from morphological, molecular and geographic data that the group contains nine species: Bembidion ampliatum, B. breve, B. geopearlis, B. laxatum, B. lividulum, B. oromaia, B. saturatum, B. testatum and B. vulcanix. We describe three species (B. geopearlis, B. oromaia and B. vulcanix) as new and resurrect four previously synonymized names (B. ampliatum, B. lividulum, B. saturatum and B. testatum). Species diversity is highest throughout the Cascades in Oregon and Washington, and Sierra Nevada of California, where up to seven species can occur in sympatry. We resolved challenging nomenclatural issues through analysis of sequences obtained from century-old type specimens by using a novel application of rDNA copy number analysis - an approach that may prove useful for other historical specimens. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
40. Properties of the single Jovian planet population and the pursuit of Solar system analogues.
- Author
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Agnew, Matthew T, Maddison, Sarah T, and Horner, Jonathan
- Subjects
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GAS giants , *STELLAR populations , *EXTRASOLAR planets , *SOLAR system , *STELLAR dynamics - Abstract
While the number of exoplanets discovered continues to increase at a rapid rate, we are still to discover any system that truly resembles the Solar system. Existing and near future surveys will likely continue this trend of rapid discovery. To see if these systems are Solar system analogues, we will need to efficiently allocate resources to carry out intensive follow-up observations. We seek to uncover the properties and trends across systems that indicate how much of the habitable zone is stable in each system to provide focus for planet hunters. We study the dynamics of all known single Jovian planetary systems to assess the dynamical stability of the habitable zone around their host stars. We perform a suite of simulations of all systems where the Jovian planet will interact gravitationally with the habitable zone, and broadly classify these systems. Besides the system's mass ratio (
M pl/M star), the Jovian planet's semimajor axis (a pl), and eccentricity (e pl), we find that there are no underlying system properties which are observable that indicate the potential for planets to survive within the system's habitable zone. We useM pl/M star,a pl, ande pl to generate a parameter space over which the unstable systems cluster, thus allowing us to predict which systems to exclude from future observational or numerical searches for habitable exoplanets. We also provide a candidate list of 20 systems that have completely stable habitable zones and Jovian planets orbiting beyond the habitable zone as potential first-order Solar system analogues. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
41. Ceragenins are active against drug-resistant Candida auris clinical isolates in planktonic and biofilm forms.
- Author
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Hashemi, Marjan M, Rovig, John, Holden, Brett S, Taylor, Maddison F, Weber, Scott, Wilson, John, Hilton, Brian, Zaugg, Aaron L, Ellis, Samuel W, Yost, Connor D, Finnegan, Patrick M, Kistler, Charles K, Berkow, Elizabeth L, Deng, Shenglou, Lockhart, Shawn R, Peterson, Marnie, and Savage, Paul B
- Subjects
CANDIDIASIS ,DRUG resistance ,ANTIFUNGAL agents ,BIOFILMS ,MYCOSES - Abstract
Background: Candida auris has emerged as a serious threat to human health. Of particular concern are the resistance profiles of many clinical isolates, with some being resistant to multiple classes of antifungals.Objectives: Measure susceptibilities of C. auris isolates, in planktonic and biofilm forms, to ceragenins (CSAs). Determine the effectiveness of selected ceragenins in gel and cream formulations in eradicating fungal infections in tissue explants.Materials and methods: A collection of 100 C. auris isolates available at CDC was screened for susceptibility to a lead ceragenin. A smaller collection was used to characterize antifungal activities of other ceragenins against organisms in planktonic and biofilm forms. Effects of ceragenins on fungal cells and biofilms were observed via microscopy. An ex vivo model of mucosal fungal infection was used to evaluate formulated forms of lead ceragenins.Results: Lead ceragenins displayed activities comparable to those of known antifungal agents against C. auris isolates with MICs of 0.5-8 mg/L and minimum fungicidal concentrations (MFCs) of 2-64 mg/L. No cross-resistance with other antifungals was observed. Fungal cell morphology was altered in response to ceragenin treatment. Ceragenins exhibited activity against sessile organisms in biofilms. Gel and cream formulations including 2% CSA-44 or CSA-131 resulted in reductions of over 4 logs against established fungal infections in ex vivo mucosal tissues.Conclusions: Ceragenins demonstrated activity against C. auris, suggesting that these compounds warrant further study to determine whether they can be used for topical applications to skin and mucosal tissues for treatment of infections with C. auris and other fungi. [ABSTRACT FROM AUTHOR]- Published
- 2018
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42. Stable habitable zones of single Jovian planet systems.
- Author
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Agnew, Matthew T., Maddison, Sarah T., Thilliez, Elodie, and Horner, Jonathan
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- *
GAS giants , *TELESCOPES , *COMPUTER simulation - Abstract
With continued improvement in telescope sensitivity and observational techniques, the search for rocky planets in stellar habitable zones is entering an exciting era. With so many exoplanetary systems available for follow-up observations to find potentially habitable planets, one needs to prioritize the ever-growing list of candidates. We aim to determine which of the known planetary systems are dynamically capable of hosting rocky planets in their habitable zones, with the goal of helping to focus future planet search programmes. We perform an extensive suite of numerical simulations to identify regions in the habitable zones of single Jovian planet systems where Earth-mass planets could maintain stable orbits, specifically focusing on the systems in the Catalog of Earth-like Exoplanet Survey Targets (CELESTA). We find that small, Earth-mass planets can maintain stable orbits in cases where the habitable zone is largely, or partially, unperturbed by a nearby Jovian, and that mutual gravitational interactions and resonant mechanisms are capable of producing stable orbits even in habitable zones that are significantly or completely disrupted by a Jovian. Our results yield a list of 13 single Jovian planet systems in CELESTA that are not only capable of supporting an Earth-mass planet on stable orbits in their habitable zone, but for which we are also able to constrain the orbits of the Earth-mass planet such that the induced radial velocity signals would be detectable with next generation instruments. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
43. New constraints on the millimetre emission of six debris discs.
- Author
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Marshall, Jonathan P., Maddison, S. T., Thilliez, E., Matthews, B. C., Wilner, D. J., Greaves, J. S., and Holland, W. S.
- Subjects
- *
CIRCUMSTELLAR matter , *STARS , *PLANETARY systems , *PROTOPLANETARY disks , *PLANETESIMALS - Abstract
The presence of dusty debris around main-sequence stars denotes the existence of planetary systems. Such debris discs are often identified by the presence of excess continuum emission at infrared and (sub-)millimetre wavelengths, with measurements at longer wavelengths tracing larger and cooler dust grains. The exponent of the slope of the disc emission at submillimetre wavelengths, 'q', defines the size distribution of dust grains in the disc. This size distribution is a function of the rigid strength of the dust producing parent planetesimals. As a part of the survey 'PLAnetesimals around TYpical Pre-main seqUence Stars', we observed six debris discs at 9 mm using the Australian Telescope Compact Array. We obtain marginal (~3σ) detections of three targets: HD 105, HD 61005 and HD 131835. Upper limits for the three remaining discs, HD 20807, HD 109573 and HD 109085 provide further constraint of the (sub-)millimetre slope of their spectral energy distributions. The values of q (or their limits) derived from our observations are all smaller than the oft-assumed steady-state collisional cascade model (q = 3.5), but lie well within the theoretically expected range for debris discs q ~ 3-4. The measured q values for our targets are all <3.3, consistent with both collisional modelling results and theoretical predictions for parent planetesimal bodies being 'rubble piles' held together loosely by their self-gravity. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
44. Self-induced dust traps: overcoming planet formation barriers.
- Author
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Gonzalez, J.-F., Laibe, G., and Maddison, S. T.
- Subjects
PLANETESIMALS ,PROTOPLANETARY disks ,DUST ,INTERSTELLAR medium ,ALTERNATIVE grains - Abstract
Planet formation is thought to occur in discs around young stars by the aggregation of small dust grains intomuch larger objects. The growth from grains to pebbles and from planetesimals to planets is now fairly well understood. The intermediate stage has however been found to be hindered by the radial-drift and fragmentation barriers. We identify a powerful mechanism in which dust overcomes both barriers. Its key ingredients are (i) backreaction from the dust on to the gas, (ii) grain growth and fragmentation and (iii) large-scale gradients. The pile-up of growing and fragmenting grains modifies the gas structure on large scales and triggers the formation of pressure maxima, in which particles are trapped. We show that these selfinduced dust traps are robust: they develop for a wide range of disc structures, fragmentation thresholds and initial dust-to-gas ratios. They are favoured locations for pebbles to grow into planetesimals, thus opening new paths towards the formation of planets. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
45. Focal CA3 hippocampal subfield atrophy following LGI1 VGKC-complex antibody limbic encephalitis.
- Author
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Miller, Thomas D., Chong, Trevor T.-J., Aimola Davies, Anne M., Ng, Tammy W. C., Johnson, Michael R., Irani, Sarosh R., Vincent, Angela, Husain, Masud, Jacob, Saiju, Maddison, Paul, Kennard, Christopher, Gowland, Penny A., and Rosenthal, Clive R.
- Subjects
VOLTAGE-gated ion channels ,HIPPOCAMPUS diseases ,IMMUNOREGULATION ,ENCEPHALITIS ,ORNITHINE aminotransferase deficiency ,CENTRAL nervous system viral diseases - Abstract
Magnetic resonance imaging has linked chronic voltage-gated potassium channel (VGKC) complex antibody-mediated limbic encephalitis with generalized hippocampal atrophy. However, autoantibodies bind to specific rodent hippocampal subfields. Here, human hippocampal subfield (subiculum, cornu ammonis 1-3, and dentate gyrus) targets of immunomodulation-treated LGI1 VGKC-complex antibody-mediated limbic encephalitis were investigated using in vivo ultra-high resolution (0.39 × 0.39 × 1.0 mm3) 7.0 T magnetic resonance imaging [n = 18 patients, 17 patients (94%) positive for LGI1 antibody and one patient negative for LGI1/CASPR2 but positive for VGKC-complex antibodies, mean age: 64.0 ± 2.55 years, median 4 years post-limbic encephalitis onset; n = 18 controls]. First, hippocampal subfield quantitative morphometry indicated significant volume loss confined to bilateral CA3 [F(1,34) = 16.87, P < 0.0001], despite hyperintense signal evident in 5 of 18 patients on presentation. Second, early and later intervention (<3 versus >3 months from symptom onset) were associated with CA3 atrophy. Third, whole-brain voxel-by-voxel morphometry revealed no significant grey matter loss. Fourth, CA3 subfield atrophy was associated with severe episodic but not semantic amnesia for postmorbid autobiographical events that was predicted by variability in CA3 volume. The results raise important questions about the links with histopathology, the impact of the observed focal atrophy on other CA3-mediated reconstructive and episodic mechanisms, and the role of potential antibody-mediated pathogenicity as part of the pathophysiology cascade in humans. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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- View/download PDF
46. mHealth Technologies to Influence Physical Activity and Sedentary Behaviors: Behavior Change Techniques, Systematic Review and Meta-Analysis of Randomized Controlled Trials.
- Author
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Direito, Artur, Carraça, Eliana, Rawstorn, Jonathan, Whittaker, Robyn, Maddison, Ralph, and Carraça, Eliana
- Subjects
MOBILE health ,PHYSICAL activity ,SEDENTARY behavior ,HEALTH behavior ,SYSTEMATIC reviews ,RANDOMIZED controlled trials - Abstract
Background: mHealth programs offer potential for practical and cost-effective delivery of interventions capable of reaching many individuals.Purpose: To (1) compare the effectiveness of mHealth interventions to promote physical activity (PA) and reduce sedentary behavior (SB) in free-living young people and adults with a comparator exposed to usual care/minimal intervention; (2) determine whether, and to what extent, such interventions affect PA and SB levels and (3) use the taxonomy of behavior change techniques (BCTs) to describe intervention characteristics.Methods: A systematic review and meta-analysis following PRISMA guidelines was undertaken to identify randomized controlled trials (RCTs) comparing mHealth interventions with usual or minimal care among individuals free from conditions that could limit PA. Total PA, moderate-to-vigorous intensity physical activity (MVPA), walking and SB outcomes were extracted. Intervention content was independently coded following the 93-item taxonomy of BCTs.Results: Twenty-one RCTs (1701 participants-700 with objectively measured PA) met eligibility criteria. SB decreased more following mHealth interventions than after usual care (standardised mean difference (SMD) -0.26, 95 % confidence interval (CI) -0.53 to -0.00). Summary effects across studies were small to moderate and non-significant for total PA (SMD 0.14, 95 % CI -0.12 to 0.41); MVPA (SMD 0.37, 95 % CI -0.03 to 0.77); and walking (SMD 0.14, 95 % CI -0.01 to 0.29). BCTs were employed more frequently in intervention (mean = 6.9, range 2 to 12) than in comparator conditions (mean = 3.1, range 0 to 10). Of all BCTs, only 31 were employed in intervention conditions.Conclusions: Current mHealth interventions have small effects on PA/SB. Technological advancements will enable more comprehensive, interactive and responsive intervention delivery. Future mHealth PA studies should ensure that all the active ingredients of the intervention are reported in sufficient detail. [ABSTRACT FROM AUTHOR]- Published
- 2017
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- View/download PDF
47. Numerical search for a potential planet sculpting the young disc of HD 115600.
- Author
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Thilliez, E. and Maddison, S. T.
- Subjects
- *
PLANETARY research , *NUMERICAL analysis , *PLANETARY orbits , *MARKOV chain Monte Carlo , *SAMPLING (Process) , *CENTAURUS (Constellation) - Abstract
Radial and azimuthal features (such as disc offsets and eccentric rings) seen in high-resolution images of debris discs provide us with the unique opportunity of finding potential planetary companions that betray their presence by gravitationally sculpting such asymmetric features. The young debris disc around HD 115600, imaged recently by the Gemini Planet Imager, is such a disc with an eccentricity e~0.1-0.2 and a projected offset from the star of~4 au. Using our modified N-body code that incorporates radiation forces, we first aim to determine the orbit of a hidden planetary companion potentially responsible for shaping the disc. We run a suite of simulations covering a broad range of planetary parameters using a Monte Carlo Markov Chain sampling method and create synthetic images from which we extract the geometric disc parameters to be compared with the observed and model-derived quantities. We then repeat the study using a traditional grid to explore the planetary parameter space and then aim to compare the efficiency of both sampling methods. We find a planet of 7.8 MJ orbiting at 30 au with an eccentricity of e = 0.2 to be the best fit to the observations of HD 115600. Technically, such planet has a contrast detectable by direct imaging, however the system's orientation does not favour such detection. In this study, at equal number of explored planetary configurations, the Monte Carlo Markov Chain not only converges faster but provides a better fit than a traditional grid. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
48. On the maximum grain size entrained by photoevaporative winds.
- Author
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Hutchison, Mark A., Laibe, Guillaume, and Maddison, Sarah T.
- Subjects
PROTOPLANETARY disks ,ULTRAVIOLET radiation ,WIND power ,PHOTOMETRY ,MICROSTRUCTURE - Abstract
We model the behaviour of dust grains entrained by photoevaporation-driven winds from protoplanetary discs assuming a non-rotating, plane-parallel disc. We obtain an analytic expression for the maximum entrainable grain size in extreme-UV radiation-driven winds, which we demonstrate to be proportional to the mass-loss rate of the disc. When compared with our hydrodynamic simulations, the model reproduces almost all of the wind properties for the gas and dust. In typical turbulent discs, the entrained grain sizes in the wind are smaller than the theoretical maximum everywhere but the inner disc due to dust settling. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
49. Tight control of disease activity fails to improve body composition or physical function in rheumatoid arthritis patients.
- Author
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Lemmey, Andrew B., Wilkinson, Thomas J., Clayton, Rebecca J., Sheikh, Fazal, Whale, John, Jones, Hope S. J., Ahmad, Yasmeen A., Chitale, Sarang, Jones, Jeremy G., Maddison, Peter J., and O'Brien, Thomas D.
- Subjects
ADIPOSE tissues ,ANALYSIS of variance ,ANTHROPOMETRY ,BODY composition ,HUMAN body composition ,CACHEXIA ,EXERCISE tests ,LIFE skills ,MUSCLE contraction ,RHEUMATOID arthritis ,STATISTICS ,DISEASE management ,DATA analysis ,TREATMENT effectiveness ,DISEASE remission ,CROSS-sectional method ,SEVERITY of illness index ,FUNCTIONAL assessment ,DESCRIPTIVE statistics ,DISEASE complications - Abstract
Objective. RA typically features rheumatoid cachexia [loss of muscle mass (MM) and excessive total fat mass (TFM), especially trunk FM], which contributes to physical disability. Since rheumatoid cachexia is driven by inflammation, it would be anticipated that the success of tight control of disease activity, such as treat-to-target (T2T), in attenuating inflammation would benefit body composition and physical function. This aim of this cross-sectional study was to assess the impact of T2T on body composition and objectively assessed function in RA patients. Methods. A total of 82 RA patients exclusively treated by T2T, were compared with 85 matched sedentary healthy controls (HCs). Body composition was estimated by DXA, with appendicular lean mass the surrogate measure of total MM. Physical function was assessed by knee extensor strength, handgrip strength, 30 s sit-to-stands, 80 up and go, and 500 walk (tests which reflect the ability to perform activities of daily living). Results. Although generally well treated (mean DAS28 = 2.8, with 49% in remission), RA patients had ~10% proportionally less appendicular lean mass and were considerably fatter (by ~27%), particularly in the trunk (~32%), than HCs. All measures of function were 24-34% poorer in the RA patients relative to HC. Conclusions. Despite marked improvements in disease control (most patients achieving or approaching remission), the relative loss of MM and increased adiposity in RA patients compared with matched HCs was similar to that observed pre-T2T. Additionally, performance of objective function tests was unchanged from that reported by our group for pre-T2T RA patients. Thus T2T, even in responsive RA patients, did not attenuate rheumatoid cachexia or improve objectively assessed function. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
50. On dust entrainment in photoevaporative winds.
- Author
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Hutchison, Mark A., Price, Daniel J., Laibe, Guillaume, and Maddison, Sarah T.
- Subjects
DUST ,ENTRAINMENT (Physics) ,EVAPORATION model (Nuclear physics) ,PROTOPLANETARY disks ,HYDRODYNAMICS ,ULTRAVIOLET radiation ,CIRCUMSTELLAR matter ,WINDS - Abstract
We investigate dust entrainment by photoevaporative winds in protoplanetary discs using dusty smoothed particle hydrodynamics. We use unequal-mass particles to resolve more than five orders of magnitude in disc/outflow density and a one-fluid formulation to efficiently simulate an equivalent magnitude range in drag stopping time. We find that only micron-sized dust grains and smaller can be entrained in extreme-UV radiation-driven winds. The maximum grain size is set by dust settling in the disc rather than aerodynamic drag in the wind. More generally, there is a linear relationship between the base flow density and the maximum entrainable grain size in the wind. A pileup of micron-sized dust grains can occur in the upper atmosphere at critical radii in the disc as grains decouple from the low-density wind. Entrainment is a strong function of location in the disc, resulting in a size sorting of grains in the outflow - the largest grain being carried out between 10 and 20 au. The peak dust density for each grain size occurs at the inner edge of its own entrainment region. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
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