2,298 research outputs found
Does a shell matter for defence? Chemical deterrence in two cephalaspidean gastropodes with calcified shells
Opisthobranch molluscs show an evolutionary trend to reduce, internalize and lose the shell. Many of them base their defensive strategies on natural deterrent products and current evolutionary theory suggests that the acquisition of chemical defences preceded shell reduction and loss, which has characterized the evolution of this group. Here we show that basal, shelled opisthobranch molluscs are defended against sympatric predators even if their protective shell is removed. The cephalaspideans Bulla striata and Haminoea orbignyana, both with distinct shell calcification, significantly deterred feeding by sympatric crab and fish predators, both in laboratory and field assays. However, our results argue against a progressive increment of chemical defences associated with shell reduction, because the cephalaspidean with the more fully calcified shell, Bulla striata, was also the more deterrent. These findings suggest that effective chemical defences might have evolved independently from shell loss, at least in basal opisthobranchs such as cephalaspideans
Contact allergy to local anaesthetics–value of patch testing with a caine mix in the baseline series
BACKGROUND:
Contact allergy to local anaesthetics is relatively common. Patch testing with benzocaine in the European baseline series is recommended for diagnosis, even though a caine mix has been previously suggested to be superior.
OBJECTIVES:
To assess the frequency and patterns of contact allergy to local anaesthetics by using a caine mix (benzocaine, tetracaine, and cinchocaine) in the baseline series, and evaluate its efficiency as compared with benzocaine alone.
METHODS:
We reviewed the results of 2736 patch tests performed between 2000 and 2010, identifying patients with positive reactions to caine mix or to one of seven local anaesthetics.
RESULTS:
One hundred and twelve patients (4.1%) had at least one allergic reaction to local anaesthetics; 86 were tested with all seven local anaesthetics, resulting in 71 reactions in 53 patients. Cinchocaine gave the most reactions (50.7%); these occurred as a single reaction in 83.3% of patients, mostly with current or past relevance (97%). Benzocaine represented 22.5% of reactions, many of which were non-relevant (44%) or resulting from cross-reactions with para-compounds.
CONCLUSIONS:
Almost 70% of allergic reactions to local anaesthetics would have been missed if benzocaine had been used as a screening allergen. This study supports a recommendation to replace benzocaine with a caine mix containing cinchocaine in the baseline patch test series
Combustion behavior of Jet-A1 single droplets and its blends with Hydroprocessed Vegetable Oil in a drop tube furnace
The aeronautical sector contributes significantly to greenhouse gases and pollutant emissions. The negative impact of these emissions in the environment has raised awareness for the introduction of alternative and greener fuels. The implementation of alternative fuels remains one of the main challenges for this sector in the near future. The aeronautical industry is characterized by the dependence on single fossil fuel and by a long service time of its assets. For these reasons, the main research drive has been around the development of “drop-in” fuels, which are alternative fuels that can be used in the already existing fleet without significant modifications.
One of the proposed solutions is the blending of biofuels with jet fuel, which would allow the use of greener fuels and a reduction in greenhouse gases and emissions without significant changes in the existing companies’ fleets. In this context, the present work evaluates the ignition and the combustion of single droplets of jet-fuel, hydroprocessed vegetable oil (NExBTL), and their mixtures in a drop tube furnace. The main research focus of this study is to evaluate the influence of the mixture composition in the fuel-burning characteristics.
Droplets with diameters of 155 ± 5 μm, produced by a commercial droplet generator, were injected into the top of the drop tube furnace. Three temperatures were investigated 900, 1000, and 1100 °C. The ignition and combustion of the droplets were evaluated through the images obtained with a high-speed camera (CR600x2) coupled with a high magnification lens (Navitar 6000 zoom lens) and treated with an edge detection algorithm. The images allowed for the observation of the burning phenomena, and the data reported the temporal evolution of the droplet sizes and burning rates. The pure fuels and mixtures followed the D2 law, except for the mixture with 75% jet-fuel/ 25% biofuel at 1100 °C that reveals disruptive burning phenomena contributing to the enhancement of the single droplet combustion. The disruptive burning phenomena are related to the appearance of “puffing” and micro-explosions at the end of the droplet lifetime.Fundação para a Ciência e a Tecnologiainfo:eu-repo/semantics/publishedVersio
An architecture for interoperability and ubiquity of medical information
In critical situations, such as decision making in healthcare, is necessary to have access to all the patient’s information, this information must be reliable, and must be accessed in an easy and fast way. These requirements make medical information systems of extreme importance. However in today’s molds and with the advent of the Internet and mobile devices, a paradigm shift, from the current isolated systems to interoperable distributed systems, that take advantage of ubiquitous computing, is needed. The present work proposes an architecture that aims to answer the needs of
interoperability between heterogeneous systems and the need of ubiquity of medical information systems
Recommended from our members
Exome Sequencing and Complex Disease: Practical Aspects of Rare Variant Association Studies
Genetic association and linkage studies can provide insights into complex disease biology, guiding the development of new diagnostic and therapeutic strategies. Over the past decade, genetic association studies have largely focused on common, easy to measure genetic variants shared between many individuals. These common variants typically have subtle functional consequence and translating the resulting association signals into biological insights can be challenging. In the last few years, exome sequencing has emerged as a cost-effective strategy for extending these studies to include rare coding variants, which often have more marked functional consequences. Here, we provide practical guidance in the design and analysis of complex trait association studies focused on rare, coding variants
Charged shells in Lovelock gravity: Hamiltonian treatment and physical implications
Using a Hamiltonian treatment, charged thin shells in spherically symmetric
spacetimes in d dimensional Lovelock-Maxwell theory are studied. The
coefficients of the theory are chosen to obtain a sensible theory, with a
negative cosmological constant appearing naturally. After writing the action
and the Lagrangian for a spacetime comprised of an interior and an exterior
regions, with a thin shell as a boundary in between, one finds the Hamiltonian
using an ADM description. For spherically symmetric spacetimes, one reduces the
relevant constraints. The dynamic and constraint equations are obtained. The
vacuum solutions yield a division of the theory into two branches, d-2k-1>0
(which includes general relativity, Born-Infeld type theories) and d-2k-1=0
(which includes Chern-Simons type theories), where k gives the highest power of
the curvature in the Lagrangian. An additional parameter, chi, gives the
character of the vacuum solutions. For chi=1 the solutions have a black hole
character. For chi=-1 the solutions have a totally naked singularity character.
The integration through the thin shell takes care of the smooth junction. The
subsequent analysis is divided into two cases: static charged thin shell
configurations, and gravitationally collapsing charged dust shells. Physical
implications are drawn: if such a large extra dimension scenario is correct,
one can extract enough information from the outcome of those collapses as to
know, not only the actual dimension of spacetime, but also which particular
Lovelock gravity, is the correct one.Comment: 25 pages, 9 figure
Deep Learning in Radiation Oncology Treatment Planning for Prostate Cancer: A Systematic Review
Radiation oncology for prostate cancer is important as it can decrease the morbidity and mortality associated with this disease. Planning for this modality of treatment is both fundamental, time-consuming and prone to human-errors, leading to potentially avoidable delays in start of treatment. A fundamental step in radiotherapy planning is contouring of radiation targets, where medical specialists contouring, i.e., segment, the boundaries of the structures to be irradiated. Automating this step can potentially lead to faster treatment planning without a decrease in quality, while increasing time available to physicians and also more consistent treatment results. This can be framed as an image segmentation task, which has been studied for many decades in the fields of Computer Vision and Machine Learning. With the advent of Deep Learning, there have been many proposals for different network architectures achieving high performance levels. In this review, we searched the literature for those methods and describe them briefly, grouping those based on Computed Tomography (CT) or Magnetic Resonance Imaging (MRI). This is a booming field, evidenced by the date of the publications found. However, most publications use data from a very limited number of patients, which presents an obstacle to deep learning models training. Although the performance of the models has achieved very satisfactory results, there is still room for improvement, and there is arguably a long way before these models can be used safely and effectively in clinical practice. (c) 2020, Springer Science+Business Media, LLC, part of Springer Nature
- …