178 research outputs found
Diagnosis, treatment and long-term outcome of solitary fibrous tumours of the pleura
Objective: Solitary fibrous tumours of the pleura (SFTP) are rare and can histologically be differentiated into benign and malignant forms. The aim of this study is to present new cases, and discuss up-to-date preoperative examinations, the role of video-assisted thoracic surgery and long-term outcome. Methods: Between 1993 and 2006, 27 SFTPs were diagnosed (14 females, mean age±SD, 62.3±9.6 years) at our institution. Medical records were reviewed, and follow-up was obtained by repeated examinations or contact with general practitioners. Results: SFTPs were associated with symptoms in 63% of all cases. In the six patients in which positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) was performed preoperatively, malignant lesions were all found to be positive. Complete resection was achieved by video-assisted thoracic surgery in 15 and anterolateral thoracotomy in 12 patients. Mean hospital stay was shorter for patients operated by video-assisted thoracic surgery compared to thoracotomy, 4.5 (range 3-6) versus 7.5 (range 4-25) days, respectively (p≪0.01). Histology revealed 17 benign and 10 malignant SFTP. Mean±SD tumour diameter of malignant SFTPs was larger than in benign forms, 11.9±7.1 versus 6.1±3.5cm, respectively (p≪0.01). Tumour recurrence was recognised in four patients with malignant SFTPs at a median time interval after surgery of 38 (range 6-122) months, two late deaths occurred resulting from tumour recurrences. Conclusions: SFTPs can be treated minimally invasively by video-assisted thoracic surgery with short hospital stay. Large SFTPs with increased FDG-uptake have a high likelihood for malignancy. Long-term follow-up is mandatory in malignant SFTPs because of late recurrences associated with deat
A new design for honey bee hoarding cages for laboratory experiments
Honey bees are the subject of research around the world due to their great economic importance and current population declines (vanEngelsdorp and Meixner, 2010). Many studies cannot be conducted at the colony level. Controlled cage experiments provide insight into behavioural interactions (Elzen et al., 2001), diseases (MartÃn-Hernández et al., 2009), nutritional requirements (Altaye et al., 2010) and effects of insecticides and genetically engineered plants on these important pollinators (Malone et al., 1999; Medrzycki et al., 2003).A grant from BBSRC, Defra, NERC,
the Scottish Government and the Wellcome Trust, under the Insect
Pollinators Initiative (BBI000968/1)http://www.ibra.org.uk/am2014ab201
Honeybees and nectar nicotine : deterrence and reduced survival versus potential health benefits
Secondary metabolites produced by plants for herbivore defence are often found in floral nectar, but their
effect on the foraging behaviour and physiological performance of pollinators is largely unknown. Nicotine
is highly toxic to most herbivores, and nicotine-based insecticides may contribute to current pollinator
declines. We examined the effects of nectar nicotine on honeybee foraging choices and worker
longevity. Free-flying honeybee (Apis mellifera scutellata) workers from six colonies were given a choice
between multiple nicotine concentrations (0–1000 lM) in artificial nectar (0.15–0.63 M sucrose). The
dose-dependent deterrent effect of nicotine was stronger in lower sugar concentrations, but even the
highest nicotine concentrations did not completely repel honeybees, i.e. bees did not stop feeding on
these diets. Nicotine in nectar acts as a partial repellent, which may keep pollinators moving between
plants and enhance cross-pollination. In the second part of the study, newly emerged workers from 12
colonies were caged and fed one of four nicotine concentrations (0–300 lM) in 0.63 M sucrose for
21 days. Moderate (630 lM) nicotine concentrations had no significant detrimental effect, but high nicotine
concentrations reduced the survival of caged workers and their nectar storage in the honey comb. In
contrast, worker groups that survived poorly on sugar-only diets demonstrated increased survival on all
nicotine diets. In the absence of alternative nectar sources, honeybees tolerate naturally occurring nectar
nicotine concentrations; and low concentrations can even be beneficial to honeybees. However, high nicotine
concentrations may have a detrimental effect on colony fitness.http://www.elsevier.com/ locate/ jinsphyshb2014ab201
Honeybees prefer warmer nectar and less viscous nectar, regardless of sugar concentration
The internal temperature of flowers may be higher than air temperature, and warmer nectar could offer energetic advantages for honeybee thermoregulation, as well as being easier to drink owing to its lower viscosity. We investigated the responses of Apis mellifera scutellata (10 colonies) to warmed 10% w/w sucrose solutions, maintained at 20–35°C, independent of low air temperatures, and to 20% w/w sucrose solutions with the viscosity increased by the addition of the inert polysaccharide Tylose (up to the equivalent of 34.5% sucrose). Honeybee crop loads increased with nectar temperature, as did the total consumption of sucrose solutions over 2 h by all bees visiting the feeders. In addition, the preference of marked honeybees shifted towards higher nectar temperatures with successive feeder visits. Crop loads were inversely proportional to the viscosity of the artificial nectar, as was the total consumption of sucrose solutions over 2 h. Marked honeybees avoided higher nectar viscosities with successive feeder visits. Bees thus showed strong preferences for both warmer and less viscous nectar, independent of changes in its sugar concentration. Bees may benefit from foraging on nectars that are warmer than air temperature for two reasons that are not mutually exclusive: reduced thermoregulatory costs and faster ingestion times due to the lower viscosity.University of Pretoria and the South African National Research Foundationhttp://rspb.royalsocietypublishing.org/hb2014ab201
Antioxidant supplementation can reduce the survival costs of excess amino acid intake in honeybees
Over-consuming amino acids is associated with reduced survival in many species, including honeybees.
The mechanisms responsible for this are unclear but one possibility is that excessive intake of amino
acids increases oxidative damage. If this is the case, antioxidant supplementation may help reduce the
survival costs of high amino acid intake. We tested this hypothesis in African honeybees (Apis mellifera
scutellata) using the major antioxidant in green tea, epigallocatechin-3-gallate (EGCG). We first determined
the dose-range of EGCG that improved survival of caged honeybees fed sucrose solution. We then
provided bees with eight diets that differed in their ratio of essential amino acids (EAA) to carbohydrate
(C) (0:1, 1:250, 1:100, 1:75, 1:50, 1:25, 1:10, 1:5 EAA:C) and also in their EGCG dose (0.0 or 0.4 mM). We
found that bees fed sucrose only solution survived better than bees fed EAA diets. Despite this, bees preferred
a diet that contained intermediate ratios of EAA:C (ca. 1:25), which may represent the high
demands for nitrogen of developing nurse bees. EGCG supplementation improved honeybee survival
but only at an intermediate dose (0.3–0.5 mM) and in bees fed low EAA diets (1:250, 1:100 EAA:C). That
EGCG counteracted the lifespan reducing effects of eating low EAA diets suggests that oxidative damage
may be involved in the association between EAAs and lifespan in honeybees. However, that EGCG had no
effect on survival in bees fed high EAA diets suggests that there are other physiological costs of over-consuming
EAAs in honeybees.A grant from the BBSRC, NERC, the Wellcome Trust, Defra, and the Scottish Government under the Insect Pollinators Initiative (BB/I000968/1).http://www.elsevier.com/locate/jinsphyshj201
Swabian MOSES 2021: An interdisciplinary field campaign for investigating convective storms and their event chains
The Neckar Valley and the Swabian Jura in southwest Germany comprise a hotspot for severe convective storms, causing tens of millions of euros in damage each year. Possible reasons for the high frequency of thunderstorms and the associated event chain across compartments were investigated in detail during the hydro-meteorological field campaign Swabian MOSES carried out
between May and September 2021. Researchers from various disciplines established more than 25 temporary ground-based stations equipped with state-of-the-art in situ and remote sensing observation systems, such as lidars, dual-polarization X- and C-band Doppler weather radars, radiosondes including stratospheric balloons, an aerosol cloud chamber, masts to measure vertical fluxes, autosamplers for water probes in rivers, and networks of disdrometers, soil moisture, and hail sensors. These fixed-site
observations were supplemented by mobile observation systems, such as a research aircraft with scanning Doppler lidar, a cosmic ray neutron sensing rover, and a storm chasing team launching swarmsondes in the vicinity of hailstorms. Seven Intensive Observation Periods (IOPs) were conducted on a total of 21 operating days. An exceptionally high number of convective events,
including both unorganized and organized thunderstorms such as multicells or supercells, occurred during the study period. This paper gives an overview of the Swabian MOSES (Modular Observation Solutions for Earth Systems) field campaign, briefly describes the observation strategy, and presents observational highlights for two IOPs
Factors Associated With COVID-19 Non-Vaccination in Switzerland: A Nationwide Study
Objectives: We compared socio-demographic characteristics, health-related variables, vaccination-related beliefs and attitudes, vaccination acceptance, and personality traits of individuals who vaccinated against COVID-19 and who did not vaccinate by December 2021. Methods: This cross-sectional study used data of 10,642 adult participants from the Corona Immunitas eCohort, an age-stratified random sample of the population of several cantons in Switzerland. We used multivariable logistic regression models to explore associations of vaccination status with socio-demographic, health, and behavioral factors. Results: Non-vaccinated individuals represented 12.4% of the sample. Compared to vaccinated individuals, non-vaccinated individuals were more likely to be younger, healthier, employed, have lower income, not worried about their health, have previously tested positive for SARS-CoV-2 infection, express lower vaccination acceptance, and/or report higher conscientiousness. Among non-vaccinated individuals, 19.9% and 21.3% had low confidence in the safety and effectiveness of SARS-CoV-2 vaccine, respectively. However, 29.1% and 26.7% of individuals with concerns about vaccine effectiveness and side effects at baseline, respectively vaccinated during the study period. Conclusion: In addition to known socio-demographic and health-related factors, non-vaccination was associated with concerns regarding vaccine safety and effectiveness
Testing Simulation Theory with Cross-Modal Multivariate Classification of fMRI Data
The discovery of mirror neurons has suggested a potential neural basis for simulation and common coding theories of action perception, theories which propose that we understand other people's actions because perceiving their actions activates some of our neurons in much the same way as when we perform the actions. We propose testing this model directly in humans with functional magnetic resonance imaging (fMRI) by means of cross-modal classification. Cross-modal classification evaluates whether a classifier that has learned to separate stimuli in the sensory domain can also separate the stimuli in the motor domain. Successful classification provides support for simulation theories because it means that the fMRI signal, and presumably brain activity, is similar when perceiving and performing actions. In this paper we demonstrate the feasibility of the technique by showing that classifiers which have learned to discriminate whether a participant heard a hand or a mouth action, based on the activity patterns in the premotor cortex, can also determine, without additional training, whether the participant executed a hand or mouth action. This provides direct evidence that, while perceiving others' actions, (1) the pattern of activity in premotor voxels with sensory properties is a significant source of information regarding the nature of these actions, and (2) that this information shares a common code with motor execution
A Common Anterior Insula Representation of Disgust Observation, Experience and Imagination Shows Divergent Functional Connectivity Pathways
Similar brain regions are involved when we imagine, observe and execute an action. Is the same true for emotions? Here, the same subjects were scanned while they (a) experience, (b) view someone else experiencing and (c) imagine experiencing gustatory emotions (through script-driven imagery). Capitalizing on the fact that disgust is repeatedly inducible within the scanner environment, we scanned the same participants while they (a) view actors taste the content of a cup and look disgusted (b) tasted unpleasant bitter liquids to induce disgust, and (c) read and imagine scenarios involving disgust and their neutral counterparts. To reduce habituation, we inter-mixed trials of positive emotions in all three scanning experiments. We found voxels in the anterior Insula and adjacent frontal operculum to be involved in all three modalities of disgust, suggesting that simulation in the context of social perception and mental imagery of disgust share a common neural substrates. Using effective connectivity, this shared region however was found to be embedded in distinct functional circuits during the three modalities, suggesting why observing, imagining and experiencing an emotion feels so different
The conservation status of the world's freshwater molluscs
With the biodiversity crisis continuing unchecked, we need to establish levels and drivers of extinction risk, and reassessments over time, to effectively allocate conservation resources and track progress towards global conservation targets. Given that threat appears particularly high in freshwaters, we assessed the extinction risk of 1428 randomly selected freshwater molluscs using the IUCN Red List Categories and Criteria, as part of the Sampled Red List Index project. We show that close to one-third of species in our sample are estimated to be threatened with extinction, with highest levels of threat in the Nearctic, Palearctic and Australasia and among gastropods. Threat levels were higher in lotic than lentic systems. Pollution (chemical and physical) and the modification of natural systems (e.g. through damming and water abstraction) were the most frequently reported threats to freshwater molluscs, with some regional variation. Given that we found little spatial congruence between species richness patterns of freshwater molluscs and other freshwater taxa, apart from crayfish, new additional conservation priority areas emerged from our study. We discuss the implications of our findings for freshwater mollusc conservation, the adequacy of a sampled approach and important next steps to estimate trends in freshwater mollusc extinction risk over time
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