1,075 research outputs found
Wind-related orientation patterns in diurnal, crepuscular and nocturnal high-altitude insect migrants
Most insect migrants fly at considerable altitudes (hundreds of meters above the ground) where they utilize fast-flowing winds to achieve rapid and comparatively long-distance transport. The nocturnal aerial migrant fauna has been well studied with entomological radars, and many studies have demonstrated that flight orientations are frequently grouped around a common direction in a range of nocturnal insect migrants. Common orientation typically occurs close to the downwind direction (thus ensuring that a large component of the insects' self-powered speed is directed downstream), and in nocturnal insects at least, the downwind headings are seemingly maintained by direct detection of wind-related turbulent cues. Despite being far more abundant and speciose, the day-flying windborne migrant fauna has been much less studied by radar; thus the frequency of wind-related common orientation patterns and the sensory mechanisms involved in their formation remain to be established. Here, we analyze a large dataset of >600,000 radar-detected "medium-sized" windborne insect migrants (body mass from 10 to 70 mg), flying hundreds of meters above southern UK, during the afternoon, in the period around sunset, and in the middle of the night. We found that wind-related common orientation was almost ubiquitous during the day (present in 97% of all “migration events” analyzed), and was also frequent at sunset (85%) and at night (81%). Headings were systematically offset to the right of the flow at night-time (as predicted from the use of turbulence cues for flow assessment), but there was no directional bias in the offsets during the day or at sunset. Orientation "performance” significantly increased with increasing flight altitude throughout the day and night. We conclude by discussing sensory mechanisms which most likely play a role in the selection and maintenance of wind-related flight headings
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The influence of the atmospheric boundary layer on nocturnal layers of noctuids and other moths migrating over southern Britain
Insects migrating at high altitude over southern Britain have been continuously monitored by automatically-operating, vertical-looking radars over a period of several years. During some occasions in the summer months, the migrants were observed to form well-defined layer concentrations, typically at heights of 200-400 m, in the stable night-time atmosphere. Under these conditions, insects are likely to have control over their vertical movements and are selecting flight heights which are favourable for long-range migration. We therefore investigated the factors influencing the formation of these insect layers by comparing radar measurements of the vertical distribution of insect density with meteorological profiles generated by the UK Met. Office’s Unified Model (UM). Radar-derived measurements of mass and displacement speed, along with data from Rothamsted Insect Survey light traps provided information on the identity of the migrants. We present here three case studies where noctuid and pyralid moths contributed substantially to the observed layers. The major meteorological factors influencing the layer concentrations appeared to be: (a) the altitude of the warmest air, (b) heights corresponding to temperature preferences or thresholds for sustained migration and (c), on nights when air temperatures are relatively high, wind-speed maxima associated with the nocturnal jet. Back-trajectories indicated that layer duration may have been determined by the distance to the coast. Overall, the unique combination of meteorological data from the UM and insect data from entomological radar described here show considerable promise for systematic studies of high-altitude insect layering
Systematic Review and Meta-analysis of Nonsteroidal Anti-inflammatory Drugs to Improve GI Recovery After Colorectal Surgery
BACKGROUND: The management of delayed GI recovery after surgery is an unmet challenge. Uncertainty over its pathophysiology has limited previous research, but recent evidence identifies intestinal inflammation and activation of µ-opioid receptors as key mechanisms. Nonsteroidal anti-inflammatory drugs are recommended by enhanced recovery protocols for their opioid-sparing and anti-inflammatory properties.
OBJECTIVES: The purpose of this study was to explore the safety and efficacy of nonsteroidal anti-inflammatory drugs to improve GI recovery and to identify opportunities for future research.
DATA SOURCES: MEDLINE, Embase, and the Cochrane Library were systematically searched from inception up to January 2018.
STUDY SELECTION: Randomized controlled trials assessing the effect of nonsteroidal anti-inflammatory drugs on GI recovery after elective colorectal surgery were eligible.
MAIN OUTCOME MEASURES: Postoperative GI recovery, including first passage of flatus, stool, and oral tolerance, were measured.
RESULTS: Six randomized controlled trials involving 563 participants were identified. All of the participants received patient-controlled morphine and either nonsteroidal anti-inflammatory drug (nonselective: n = 4; cyclooxygenase-2 selective: n = 1; either: n = 1) or placebo. Patients receiving the active drug had faster return of flatus (mean difference: –17.73 h (95% CI, –21.26 to –14.19 h); p < 0.001), stool (–9.52 h (95% CI, –14.74 to –4.79 h); p < 0.001), and oral tolerance (–12.00 h (95% CI, –18.01 to –5.99 h); p < 0.001). Morphine consumption was reduced in the active groups of 4 studies (average reduction, 12.9–30.0 mg), and 1 study demonstrated significantly reduced measures of systemic inflammation. Nonsteroidal anti-inflammatory drugs were not associated with adverse events, but 1 study was temporarily suspended for safety.
LIMITATIONS: The data presented are relatively outdated but represent the best available evidence.
CONCLUSIONS: Nonsteroidal anti-inflammatory drugs may represent an effective and accessible intervention to improve GI recovery, but hesitancy over their use after colorectal surgery persists. Additional preclinical research to characterize their mechanisms of action, followed by well-designed clinical studies to test safety and patient-reported efficacy, should be considered
Integrating Meteorology into Research on Migration
Atmospheric dynamics strongly influence the migration of flying organisms. They affect, among others, the onset, duration and cost of migration, migratory routes, stop-over decisions, and flight speeds en-route. Animals move through a heterogeneous environment and have to react to atmospheric dynamics at different spatial and temporal scales. Integrating meteorology into research on migration is not only challenging but it is also important, especially when trying to understand the variability of the various aspects of migratory behavior observed in nature. In this article, we give an overview of some different modeling approaches and we show how these have been incorporated into migration research. We provide a more detailed description of the development and application of two dynamic, individual-based models, one for waders and one for soaring migrants, as examples of how and why to integrate meteorology into research on migration. We use these models to help understand underlying mechanisms of individual response to atmospheric conditions en-route and to explain emergent patterns. This type of models can be used to study the impact of variability in atmospheric dynamics on migration along a migratory trajectory, between seasons and between years. We conclude by providing some basic guidelines to help researchers towards finding the right modeling approach and the meteorological data needed to integrate meteorology into their own research
Peripheral blood leukocyte response and macrophage function during Eimeria adenoeides infection in turkey poults
Intestinal coccidiosis, caused by various species of Eimeria, is an economically important disease of chickens and turkeys. The peripheral blood leukocyte response and macrophage functions during a coccidial infection in turkeys have not been defined. To examine these aspects of innate immunity during primary Eimeria infection in turkeys, 4-week-old poults were orally inoculated with either 50,000 E. adenoeides oocyst (24 infected poults) or water (24 control poults). To monitor the concentrations and proportions of white blood cells (WBC) throughout the course of infection, heparinized blood was collected from 12 infected and 12 control poults prior to inoculation (day 0), and on days 4, 7, and 11 post-inoculation (PI). To study macrophage function, Sephadex-elicited abdominal exudate cells (macrophages) were collected on day 7 PI from 12 infected and 12 control poults. Macrophages were used to study phagocytosis of unopsonized and antibody-opsonized sheep red blood cells (SRBC), production of nitric oxide, and production of cytotoxic factors. E. adenoeides infection was associated with alterations in the concentration of WBC, including a decrease in the numbers of circulating lymphocytes on day 4 and a rise in lymphocytes and heterophils on day 11. Although phagocytic activity was not different in macrophages from infected and control poults, macrophages from infected poults exhibited greater cytotoxic activity. Data from these studies strongly suggest that components of innate immunity were recruited and activated during this primary infection of turkey poults with E. adenoeides. Further investigations are needed to determine the role of these components in limiting primary infection by E. adenoeides
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Near-Earth asteroid sample return missions
The rate of discovery of new NEAs and the success of D-S 1 and NEAR-Shoemaker, suggest that sample return from NEAs is now technically feasible. Here we present a summary of a recent workshop on the topic
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Migratory flight behaviour of the pollen beetle Meligethes aeneus
BACKGROUND
The field ecology of the pollen beetle Meligethes aeneus and its damaging effects on oilseed rape crops are well understood. However, the flight behaviour of M. aeneus, in particular the drivers for migratory movements across the landscape, is not well studied. We combined three established methodologies; suction traps, vertical-looking radar and high-altitude aerial netting to demonstrate that M. aeneus fly at a range of altitudes at different points during its active season.
RESULTS
By linking evidence of high-altitude mass migration with immigration of pollen beetles into oilseed rape fields, we were able to ‘ground-truth’ the results to characterise the seasonal movements of this pest across the landscape.
CONCLUSION
We demonstrate that this novel combination of methodologies can advance our understanding of the population movements of pollen beetles and could provide an opportunity to develop predictive models to estimate the severity and timing of pest outbreaks
Statistical characterisation of full-disk EUV/XUV solar irradiance and correlation with solar activity
We investigate the distribution of fluctuations in solar irradiance when
integrated over the full disk, obtained using extreme ultraviolet/soft X-ray
observations from the SOHO CELIAS/SEM instrument. This time series sums over
both the contributions of single distinguishable flares, and of many other
processes. By detrending we select events with timescales of less than a few
hours such as waves, slow flows, and CMEs. The statistics generated by this
range of phenomena can be characterised by power-law-tailed distributions. We
show that (i) during the high-activity period 2000 Jan-June the tail exponent
a(T)=1.5 +/- 0.1; (ii) during the low-activity period 1996 Jan-June a(T)=3.0
+/- 0.2; and (iii) in general a(T) decreases with increasing activity.Comment: 4 pages, 5 figures; v.2 R-squared goodness of fits adde
Improvement in the pre-hospital care of recreational drug users through the development of club specific ambulance referral guidelines
<p>Abstract</p> <p>Background</p> <p>Previously developed 'club guidelines' developed for club owners and promoters have tended to focus more on the legislative aspects of clubs, rather than the medical management of unwell clubbers within club environments. Despite this lack of guidance on the management of unwell clubbers, a significant proportion of clubs have 'club medic' rooms for managing these individuals. However, due to the lack of specific guidance on the training of staff working in these rooms and guidelines on when an ambulance should be called for an unwell clubber, there have been instances previously where clubbers have been inappropriately managed within the club environment, and often referred to hospital only after significant physiological derangement has occurred, thereby leading to an increased risk of morbidity and mortality.</p> <p>Methods</p> <p>We identified owners and promoters of local club venues within the catchment area of our Emergency Department and working jointly with them and other key stakeholders, in particular the London Ambulance Service and Metropolitan Police, identified strategies to improve pre-hospital care for clubbers who become unwell as a result of recreational drug use. These included developing guidelines detailing indications for ambulance transfer to hospital for clubbers with recreational drug toxicity and the training of club medic staff to use the guidelines</p> <p>Results</p> <p>Following the initial development of a pilot set of guidelines, an audit of their use identified training needed relating to the assessment of unwell clubbers with recreational drug toxicity and revisions required to the pilot version of the guidelines. After training related to the revised guidelines, all the club medic staff were confident in their ability to assess unwell clubbers with recreational drug toxicity, the use of the guidelines and also when to call an ambulance.</p> <p>Conclusion</p> <p>Working with key stakeholders in the local community, we have developed guidelines that can be used to improve the pre-hospital care of clubber unwell with recreational drug toxicity, and demonstrated that individuals with a variety of medical knowledge can be trained to use these guidelines. Wider dissemination of these guidelines, both regionally, nationally and potentially internationally, may help to reduce the pre-hospital morbidity and mortality associated with recreational drug toxicity encountered in club environments.</p
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