166 research outputs found
The impact of predation by marine mammals on Patagonian toothfish longline fisheries
Predatory interaction of marine mammals with longline fisheries is observed globally, leading to partial or complete loss of the catch and in some parts of the world to considerable financial loss. Depredation can also create additional unrecorded fishing mortality of a stock and has the potential to introduce bias to stock assessments. Here we aim to characterise depredation in the Patagonian toothfish (Dissostichus eleginoides) fishery around South Georgia focusing on the spatio-temporal component of these interactions. Antarctic fur seals (Arctocephalus gazella), sperm whales (Physeter macrocephalus), and orcas (Orcinus orca) frequently feed on fish hooked on longlines around South Georgia. A third of longlines encounter sperm whales, but loss of catch due to sperm whales is insignificant when compared to that due to orcas, which interact with only 5% of longlines but can take more than half of the catch in some cases. Orca depredation around South Georgia is spatially limited and focused in areas of putative migration routes, and the impact is compounded as a result of the fishery also concentrating in those areas at those times. Understanding the seasonal behaviour of orcas and the spatial and temporal distribution of âdepredation hot spotsâ can reduce marine mammal interactions, will improve assessment and management of the stock and contribute to increased operational efficiency of the fishery. Such information is valuable in the effort to resolve the human-mammal conflict for resources
The Association of Coloproctology of Great Britain and Ireland consensus guidelines in emergency colorectal surgery
ACKNOWLEDGEMENTS Review and editing: S.R. Brown, Professor of Surgery, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK. Email [email protected]. Patient summary: R.G. Arnott, Retired Professor, Patient Liaison Group, Association of Coloproctology of Great Britain and Ireland, Royal College of Surgeons of England, London, UK. Email [email protected]. Delphi review: C.P. Macklin. BMedSci BM BS FRCS DM, Consultant Colorectal Surgeon, Mid Yorkshire Hospitals, UK. Email [email protected] reviewedPublisher PD
Physical activity and depressive symptoms in adolescents: a prospective study
Background: The frequency of mental illness amongst adolescents and its potential long-term consequences make it an important topic to research in relation to risk and protective factors. Research on the relationship between physical activity and depressive symptoms in adolescents is limited. There is a particular lack of evidence from longitudinal studies. This study examines the relationship between depression and physical activity using the Research with East London Adolescents: Community Health Survey (RELACHS).Methods: This was a prospective cohort study. Participants were recruited from three Local Education Authority boroughs in East London in 2001 from year 7 (aged 11-12) and year 9 (aged 13-14) and were followed-up in 2003. All pupils in the 28 schools that took part were eligible for the study. Of the total 3,322 pupils eligible for the survey the overall response rate was 84% (2,789 pupils). A total of 2,093 (75%) pupils were also followed-up in 2003. The sample was multiethnic (73% of respondents were non-white) and deprived. Just under half of the sample was male (49%). Depressive symptoms were measured using the Short Moods and Feelings Questionnaire (SMFQ). Logistic regression analyses were used to examine the association between physical activity and depressive symptoms both cross-sectionally and longitudinally.Results: After adjustments, there was evidence for a cross-sectional association between physical activity and depressive symptoms for both boys and girls at baseline, with a decrease in the odds of depressive symptoms of about 8% for each additional hour of exercise undertaken per week (boys: odds ratio (OR) = 0.92, 95% CI 0.85 to 0.99; girls: OR = 0.92, 95% CI 0.85 to 1.00). There was no evidence for an association between a change in physical activity from baseline to follow-up and depressive symptoms at follow-up.Conclusions: This study provides some evidence for an association between level of physical activity and decreased depressive symptoms in adolescents. Further longitudinal research of these associations is required before physical activity can be recommended as an intervention for depression in adolescents
Effects of Polymer 3D Architecture, Size, and Chemistry on Biological Transport and Drug Delivery In Vitro and in Orthotopic Triple Negative Breast Cancer Models
© 2020 Wiley-VCH GmbH The size, shape, and underlying chemistries of drug delivery particles are key parameters which govern their ultimate performance in vivo. Responsive particles are desirable for triggered drug delivery, achievable through architecture change and biodegradation to control in vivo fate. Here, polymeric materials are synthesized with linear, hyperbranched, star, and micellar-like architectures based on 2-hydroxypropyl methacrylamide (HPMA), and the effects of 3D architecture and redox-responsive biodegradation on biological transport are investigated. Variations in âstealthâ behavior between the materials are quantified in vitro and in vivo, whereby reduction-responsive hyperbranched polymers most successfully avoid accumulation within the liver, and none of the materials target the spleen or lungs. Functionalization of selected architectures with doxorubicin (DOX) demonstrates enhanced efficacy over the free drug in 2D and 3D in vitro models, and enhanced efficacy in vivo in a highly aggressive orthotopic breast cancer model when dosed over schedules accounting for the biodistribution of the carriers. These data show it is possible to direct materials of the same chemistries into different cellular and physiological regions via modulation of their 3D architectures, and thus the work overall provides valuable new insight into how nanoparticle architecture and programmed degradation can be tailored to elicit specific biological responses for drug delivery
A novel application of motion analysis for detecting stress responses in embryos at different stages of development.
Motion analysis is one of the tools available to biologists to extract biologically relevant information from image datasets and has been applied to a diverse range of organisms. The application of motion analysis during early development presents a challenge, as embryos often exhibit complex, subtle and diverse movement patterns. A method of motion analysis able to holistically quantify complex embryonic movements could be a powerful tool for fields such as toxicology and developmental biology to investigate whole organism stress responses. Here we assessed whether motion analysis could be used to distinguish the effects of stressors on three early developmental stages of each of three species: (i) the zebrafish Danio rerio (stages 19 h, 21.5 h and 33 h exposed to 1.5% ethanol and a salinity of 5); (ii) the African clawed toad Xenopus laevis (stages 24, 32 and 34 exposed to a salinity of 20); and iii) the pond snail Radix balthica (stages E3, E4, E6, E9 and E11 exposed to salinities of 5, 10 and 15). Image sequences were analysed using Sparse Optic Flow and the resultant frame-to-frame motion parameters were analysed using Discrete Fourier Transform to quantify the distribution of energy at different frequencies. This spectral frequency dataset was then used to construct a Bray-Curtis similarity matrix and differences in movement patterns between embryos in this matrix were tested for using ANOSIM
Combining motion analysis and microfluidics--a novel approach for detecting whole-animal responses to test substances.
Small, early life stages, such as zebrafish embryos are increasingly used to assess the biological effects of chemical compounds in vivo. However, behavioural screens of such organisms are challenging in terms of both data collection (culture techniques, drug delivery and imaging) and data evaluation (very large data sets), restricting the use of high throughput systems compared to in vitro assays. Here, we combine the use of a microfluidic flow-through culture system, or BioWell plate, with a novel motion analysis technique, (sparse optic flow - SOF) followed by spectral analysis (discrete Fourier transformation - DFT), as a first step towards automating data extraction and analysis for such screenings. Replicate zebrafish embryos housed in a BioWell plate within a custom-built imaging system were subject to a chemical exposure (1.5% ethanol). Embryo movement was videoed before (30 min), during (60 min) and after (60 min) exposure and SOF was then used to extract data on movement (angles of rotation and angular changes to the centre of mass of embryos). DFT was subsequently used to quantify the movement patterns exhibited during these periods and Multidimensional Scaling and ANOSIM were used to test for differences. Motion analysis revealed that zebrafish had significantly altered movements during both the second half of the alcohol exposure period and also the second half of the recovery period compared to their pre-treatment movements. Manual quantification of tail flicking revealed the same differences between exposure-periods as detected using the automated approach. However, the automated approach also incorporates other movements visible in the organism such as blood flow and heart beat, and has greater power to discern environmentally-driven changes in the behaviour and physiology of organisms. We suggest that combining these technologies could provide a highly efficient, high throughput assay, for assessing whole embryo responses to various drugs and chemicals
Crop Updates 2002 - Cereals
This session covers thirty one papers from different authors:
VARIETIES AND BREEDING
1. Agronomic evaluation of wheat and barley in the central wheatbelt of Western Australia, Peter Burgess1and Gary Fawell2, 1Agritech and 2Farmanco Management
2. Evaluating stress tolerance to terminal drought by Western Australian wheats, Dean Diepeveen and Dr Tim Setter, Department of Agriculture
3. Broadscale wheat variety comparisons featuring Wyalkatchem, Jeff Russell, Department of Agriculture
4. Australian crop accreditation system variety selector, Tony Seymour, Australian Crop Accreditation System
5. Future wheat varieties, Robin Wilson, Iain Barclay,Robyn McLean, Robert Loughman, Jenny Garlinge, Bill Lambe, Neil Venn and Peter Clarke, Department of Agriculture
AGRONOMY
6. Beware of wheat variety interactions with row spacing and seed rate, Mohammad Amjad and Wal Anderson, Department of Agriculture
7. Yield and falling numbers of wheat varieties on the South Coast, Mohammad Amjad and Wal Anderson, Department of Agriculture
8. Maximising wheat variety performance through agronomic management, Wal Anderson, Raffaele Del Cima, James Bee, Darshan Sharma, Sheena Lyon, Melaine Kupsch, Mohammad Amjad, Pam Burgess, Veronika Reck, Brenda Shackley, Ray Tugwell, BindiWebb and Steve Penny Jr, Department of Agriculture
9. High impact of soil type and seasonal rainfall on optimum wheat seed rate , Raffaele Del Cima and Wal Anderson Department of Agriculture
10. 101 seasons in one day: Using the âWA Wheatâ database to predict wheat yield, James Fisher1, Bill Bowden1, Craig Scanlan1, Senthold Asseng2and Michael Robertson2 1Department of Agriculture, 2CSIRO
11. Economics of improving compact soils, M.A. Hamza1, G. McConnell2and W.K. Anderson1, 1Department of Agriculture, 2Planfarm
12. Reducing the risks in producing durum wheat in Western Australia, Md Shahajahan Miyan and Wal Anderson, Department of Agriculture
13. Taking the Why out of Wyalkatchem â the new widely adopted wheat variety, Steve Penny, Department of Agriculture
14. Influence of nutrition and environmental factors on seed vigour in wheat, Darshan Sharma, Wal Anderson and Daya Patabendige, Department of Agriculture
NUTRITION
15. N and K are important for oat yield and quality, Patrick Gethin, Stephen Loss, Tim OâDea, Ryan Guthrie and Lisa Leaver, CSBP Futurefarm
16. Effects of nitrogen and phosphorus on the grain yield and quality of noodle wheat, Tyrone Henning1, Lionel Martin1and Wal Anderson2 1Muresk Institute of Agriculture, 2Department of Agriculture
17. Assessment of a high input fertiliser regime on the yield and quality of Gairdner barley, Narelle Hill1, Simon Wallwork2and Laurence Carslake2 1Department of Agriculture, 2Wesfarmers Landmark
18. The use of Flexi-N to achieve high yielding, high protein wheat, Darren Hughes1, Lionel Martin1, Wal Anderson2and Stephen Loss3 1Muresk Institute of Agriculture, 2Department of Agriculture, 3CSBP Futurefarm
19. Are liquid phosphorus fertilisers more efficient than solid fertilisers in Western Australia?Stephen Loss, Lisa Leaver, Ryan Guthrie, Patrick Gethin and Tim OâDea, CSBP Futurefarm
20. Oats respond to phosphorus and potassium, Glenn McDonald, Department of Agriculture
PESTS AND DISEASES
21. Cereal disease diagnostics and rust monitoring, Nichole Burges and Dominie Wright, Department of Agriculture
22. Distribution and incidence of aphids and barley yellow dwarf virus in over-summering grasses in the Western Australian wheatbelt, Jenny Hawkes and Roger Jones, Centre for Legumes in Mediterranean Agriculture and Department of Agriculture
23. Spring sprays for powdery mildew control in cereals, Kith Jayasena1, Kazue Tanaka1, Vanessa Johnson1, Robert Loughman1and Josh Jury2 1Department of Agriculture, 2Wesfarmers Landmark
24. Impact of root lesion nematodes on wheat and triticale in Western Australia, Sean Kelly and Shashi Sharma, Department of Agriculture
25. Cropping options for the management of root lesion nematodes in Western Australia, Sean Kelly, Shashi Sharma and Robert Loughman, Department of Agriculture
26. Cereal rust update 2002 â new stem rust on Camm wheat, Robert Loughman1and Robert Park2 1Department of Agriculture, 2University of Sydney
27. Cereal aphids and direct feeding damage to cereals, Phil Michael, Department of Agriculture
28. A decision support system for control of aphids and BYDV in cereal crops, Debbie Thackray, Jenny Hawkes and Roger Jones, Department of Agriculture and Centre for Legumes in Mediterranean Agriculture
STORAGE
29. Aeration â opportunity for profit, Christopher Newman, Department of Agriculture
CLIMATE
30. Financial impact of frost on the Western Australian grains industry, Garren Knell and Kim Povey, ConsultAg
31. Summary of 2001 weather and seasonal prospects for 2002, David Stephens, Department of Agricultur
Crop Updates 2003 - -Katanning
This session covers sixteen papers from different authors
Breeding Cereals for Rust Resistance â are we losing the battle? Robert F. Park, University of Sydney
Stripe rust â where to now for the WA wheat industry? Robert Loughman, Department of Agriculture, Colin Wellings, University of Sydney, Greg Shea, Department of Agriculture
Oaten hay production, Jocelyn Ball, Natasha Littlewood and Lucy Creagh, Department of Agriculture
Donât rely on âSpray and Prayâ Alex Douglas, Department of Agriculture
Seasonal outlook: What is in store for 2003, David Stephens, Department of Agriculture
No-till copper, phosphorus and zinc experiments, Ross Brennan and Mike Bolland, Department of Agriculture
Wheat nutrition in the high rainfall zone, Narelle Hill, Department of Agriculture
Aphid damage to cereal grain crops, Phil Michael, Department of Agriculture
Aphid damage to canola â not all cultivars are equal, Francoise A. Berlandier and Christiaan Valentine, Department of Agriculture
Overcropping Lucerne, Roy Latta, Department of Agriculture
Future direction of field pea varieties, M. Rodger Beermier, Department of Agriculture
Selecting the right pasture for the job, Keith Devenish, Department of Agriculture
Topping up pasture seedbanks, Keith Devenish, Department of Agriculture
Baudin and Hamlin New generation of malting barleys, Blakely Paynter, Roslyn Jettner and Kevin Young, Department of Agriculture
Wheat variety performance in 2002 compared to the long term, Robin Wilson, Ian Barclay Robyn McLean, Robert Loughman, Jenny Garlinge, Bill Lambe, Neil Venn and Peter Clarke, Department of Agriculture
The role of green manure crops in renovating poor performing paddocks: Whatâs it worth? Francis Hoyle, Leanne Schulz and Judith Devenish, Department of Agricultur
Frequency drift in MR spectroscopy at 3T
Purpose: Heating of gradient coils and passive shim components is a common cause of instability in the B-0 field, especially when gradient intensive sequences are used. The aim of the study was to set a benchmark for typical drift encountered during MR spectroscopy (MRS) to assess the need for real-time field-frequency locking on MRI scanners by comparing field drift data from a large number of sites.Method: A standardized protocol was developed for 80 participating sites using 99 3T MR scanners from 3 major vendors. Phantom water signals were acquired before and after an EPI sequence. The protocol consisted of: minimal preparatory imaging; a short pre-fMRI PRESS; a ten-minute fMRI acquisition; and a long post-fMRI PRESS acquisition. Both pre- and post-fMRI PRESS were non-water suppressed. Real-time frequency stabilization/adjustment was switched off when appropriate. Sixty scanners repeated the protocol for a second dataset. In addition, a three-hour post-fMRI MRS acquisition was performed at one site to observe change of gradient temperature and drift rate. Spectral analysis was performed using MATLAB. Frequency drift in pre-fMRI PRESS data were compared with the first 5:20 minutes and the full 30:00 minutes of data after fMRI. Median (interquartile range) drifts were measured and showed in violin plot. Paired t-tests were performed to compare frequency drift pre- and post-fMRI. A simulated in vivo spectrum was generated using FID-A to visualize the effect of the observed frequency drifts. The simulated spectrum was convolved with the frequency trace for the most extreme cases. Impacts of frequency drifts on NAA and GABA were also simulated as a function of linear drift. Data from the repeated protocol were compared with the corresponding first dataset using Pearson's and intraclass correlation coefficients (ICC).Results: Of the data collected from 99 scanners, 4 were excluded due to various reasons. Thus, data from 95 scanners were ultimately analyzed. For the first 5:20 min (64 transients), median (interquartile range) drift was 0.44 (1.29) Hz before fMRI and 0.83 (1.29) Hz after. This increased to 3.15 (4.02) Hz for the full 30 min (360 transients) run. Average drift rates were 0.29 Hz/min before fMRI and 0.43 Hz/min after. Paired t-tests indicated that drift increased after fMRI, as expected (p < 0.05). Simulated spectra convolved with the frequency drift showed that the intensity of the NAA singlet was reduced by up to 26%, 44 % and 18% for GE, Philips and Siemens scanners after fMRI, respectively. ICCs indicated good agreement between datasets acquired on separate days. The single site long acquisition showed drift rate was reduced to 0.03 Hz/min approximately three hours after fMRI.Discussion: This study analyzed frequency drift data from 95 3T MRI scanners. Median levels of drift were relatively low (5-min average under 1 Hz), but the most extreme cases suffered from higher levels of drift. The extent of drift varied across scanners which both linear and nonlinear drifts were observed.</p
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