3,663 research outputs found
Advantages of enteral nutrition over parenteral nutrition
It is a strong and commonly held belief among nutrition clinicians that enteral nutrition is preferable to parenteral nutrition. We provide a narrative review of more recent studies and technical reviews comparing enteral nutrition with parenteral nutrition. Despite significant weaknesses in the existing data, current literature continues to support the use of enteral nutrition in patients requiring nutrition support, over parenteral nutrition
Interspecific variation in the limb long bones among modern rhinocerosesâextent and drivers
International audienceAmong amniotes, numerous lineages are subject to an evolutionary trend toward body mass and size increases. Large terrestrial species may face important constraints linked to weight bearing, and the limb segments are particularly affected by such constraints due to their role in body support and locomotion. Such groups showing important limb modifications related to high body mass have been called "graviportal." Often considered graviportal, rhinoceroses are among the heaviest terrestrial mammals and are thus of particular interest to understand the limb modifications related to body mass and size increase. Here, we present a morphofunctional study of the shape variation of the limb long bones among the five living rhinos to understand how the shape may vary between these species in relation with body size, body mass and phylogeny. We used three dimensional geometric morphometrics and comparative analyses to quantify the shape variation. Our results indicate that the five species display important morphological differences depending on the considered bones. The humerus and the femur exhibit noticeable interspecific differences between African and Asiatic rhinos, associated with a significant effect of body mass. The radius and ulna are more strongly correlated with body mass. While the tibia exhibits shape variation both linked with phylogeny and body mass, the fibula displays the greatest intraspecific variation. We highlight three distinct morphotypes of bone shape, which appear in accordance with the phylogeny. The influence of body mass also appears unequally expressed on the different bones. Body mass increase among the five extant species is marked by an increase of the general robustness, more pronounced attachments for muscles and a development of medial parts of the bones. Our study underlines that the morphological features linked to body mass increase are not similar between rhinos and other heavy mammals such as elephants and hippos, suggesting that the weight bearing constraint can lead to different morphological responses
Effect of simulation-based education on the preparedness of healthcare professionals for the COVID-19 pandemic : a systematic review and meta-analysis
Healthcare organizations around the world have embraced simulation to prepare healthcare professionals to the COVID-19 pandemic. However, this pandemic implies additional educational challenges in rapidly designing simulation activities, while remaining compliant with health and safety measures to prevent the spread of the virus. The effect of simulation-based education in this context remains to be evaluated. Objective: The purpose of this systematic review was to describe the features and evaluate the effect of simulation activities on the preparedness of healthcare professionals and students to safely deliver care during the COVID-19 pandemic. Methods: Databases were searched up to November 2020 using index terms and keywords related to healthcare professions, simulation, and COVID-19. All learning outcomes were considered according to the Kirkpatrick model adapted by Barr et al. (2020). Reference selection, data extraction, and quality assessment were performed in pairs and independently. Results were synthesized using meta-analytical methods and narrative summaries. Results: 22 studies were included, 21 of which were single-group studies and 14 of those included pretest/posttest assessments. Simulation activities were mostly implemented in clinical settings using manikins for training on the use of personal protective equipment, hand hygiene, identification and management of COVID-19 patients, and work processes and patient flow. Large improvements in learning outcomes after simulation activities were reported in all studies. Discussion and conclusion: Results should be interpreted cautiously due to significant threats to the internal validity of studies and the absence of control groups. However, these findings are coherent with the overall evidence on the positive effect of simulation-based education. Future studies should include control groups if feasible.Les organisations de santĂ© ont adoptĂ© la simulation pour prĂ©parer les professionnels Ă la pandĂ©mie de COVID-19. La conception en accĂ©lĂ©rĂ© de simulations tout en respectant les mesures de prĂ©vention de la propagation du virus amĂšne des dĂ©fis. Dans ces conditions, lâefficacitĂ© de la simulation reste Ă ĂȘtre Ă©valuĂ©e. Objectif : DĂ©crire les caractĂ©ristiques et Ă©valuer lâeffet de simulations sur la prĂ©paration des professionnels de la santĂ© et des Ă©tudiants pour fournir des soins sĂ©curitaires pendant cette pandĂ©mie. MĂ©thodes : Les bases de donnĂ©es ont Ă©tĂ© consultĂ©es jusquâen novembre 2020 en utilisant des descripteurs et des mots-clĂ©s relatifs aux professions de la santĂ©, Ă la simulation et Ă la COVID-19. Tous les rĂ©sultats dâapprentissage ont Ă©tĂ© considĂ©rĂ©s. La sĂ©lection des articles, lâextraction des donnĂ©es et lâĂ©valuation de la qualitĂ© ont Ă©tĂ© effectuĂ©es par paires. Les rĂ©sultats ont Ă©tĂ© synthĂ©tisĂ©s par des mĂ©thodes mĂ©ta-analytiques et des rĂ©sumĂ©s narratifs. RĂ©sultats : 22 Ă©tudes ont Ă©tĂ© incluses ; 21 Ă groupe unique et, parmi ces 21, 14 Ă©valuations prĂ©-posttest. Les simulations ont principalement Ă©tĂ© dĂ©ployĂ©es en milieux cliniques avec des mannequins pour la formation Ă lâutilisation dâĂ©quipements de protection individuelle, au lavage de mains, Ă lâidentification et la prise en charge de patients atteints de la COVID-19 et Ă lâimplantation de procĂ©dĂ©s organisationnels. Toutes les Ă©tudes rapportent des apprentissages importants aprĂšs les simulations. Discussion et conclusion : MalgrĂ© les limites de validitĂ© interne et lâabsence de groupes de contrĂŽle, ces rĂ©sultats sont cohĂ©rents avec lâĂ©tat des connaissances sur les effets positifs de la simulation. De futures Ă©tudes devraient inclure des groupes de contrĂŽle si possible
Bioinspired microstructures of chitosan hydrogel provide enhanced wear protection
We describe the fabrication of physical chitosan hydrogels exhibiting a layered structure. This
bilayered structure, as shown by SEM and confocal microscopy, is composed of a thin dense
superficial zone (SZ), covering a deeper zone (DZ) containing microchannels orientated
perpendicularly to the SZ. We show that such structure favors diffusion of macromolecules
within the hydrogel matrix up to a critical pressure, Ïc, above which channels were
constricted. Moreover, we found that the SZ provided a higher wear resistance than the DZ
which was severely damaged at a pressure equal to the elastic modulus of the gel. The
coefficient of friction (CoF) of the SZ remained independent of the applied load with ÎŒSZ =
0.38 ± 0.02, while CoF measured at DZ exhibited two regimes: an initial CoF close to the
value found on the SZ, and a CoF that decreased to ΌDZ = 0.18 ± 0.01 at pressures higher than
the critical pressure Ïc. Overall, our results show that internal structuring is a promising
avenue in controlling and improving the wear resistance of soft materials such as hydrogels
Microbial eukaryotes in the suboxic chemosynthetic ecosystem of Movile Cave, Romania
International audienceMovile Cave is a small system of partially inundated galleries in limestone settings close to the Black Sea in Southeast Romania. Isolated from the surface for 6 million years, its sulfidic, methane and ammoniarich waters harbour unique chemosynthetic prokaryotic communities that include sulphur and ammonium-metabolizing chemolithotrophs, methanogens, methanotrophs and methylotrophs. The cave also harbours cave-dwelling invertebrates and fungi, but the diversity of other microbial eukaryotes remained completely unknown. Here, we apply an 18S rRNA gene-based metabarcoding approach to study the composition of protist communities in floating microbial mats and plankton from a wellpreserved oxygen-depleted cave chamber. Our results reveal a wide protist diversity with, as dominant groups, ciliates (Alveolata), Stramenopiles, especially bicosoecids, and jakobids (Excavata). Ciliate sequences dominated both, microbial mats and plankton, followed by either Stramenopiles or excavates. Stramenopiles were more prominent in microbial mats, whereas jakobids dominated the plankton fraction of the oxygen-depleted water column. Mats cultured in the laboratory were enriched in Cercozoa. Consistent with local low oxygen levels, Movile Cave protists are most likely anaerobic or microaerophilic. Several newly detected OTU clades were very divergent from cultured species or environmental sequences in databases and represent phylogenetic novelty, notably within jakobids. Movile Cave protists likely cover a variety of ecological roles in this ecosystem including predation, parasitism, saprotrophy and possibly diverse prokaryote-protist syntrophies
Tyrosine-based rivastigmine-loaded organogels in the treatmant of Alzheimer's disease
Faculté de PharmacieOrganogels can be prepared by immobilizing an organic phase into a threedimensional
network coming from the self-assembly of a low molecular weight gelator molecule. In this work, an injectable subcutaneous organogel system based on safflower oil and a modified-tyrosine organogelator was evaluated in vivo for the delivery of rivastigmine, an acetylcholinesterase (AChE) inhibitor used in the treatment of Alzheimerâs disease. Different implant formulations were injected and the plasmatic drug concentration was assayed for up to 35 days. In parallel, the inhibition of AChE in different brain sections and the biocompatibility of the implants were monitored. The pharmacokinetic profiles were found to be influenced by the gel composition, injected dose and volume of the implant. The sustained delivery of rivastigmine was accompanied by a significant prolonged inhibition of AChE in the hippocampus, a brain structure involved in memory. The implant induced only a minimal to mild chronic inflammation and fibrosis, which was comparable to poly(D,L-lactide-co-glycolide) in situ-forming implants. These findings suggest that tyrosine-based organogels could represent an alternative approach to current
formulations for the sustained delivery of cholinesterase inhibitors.IRS
Attention-based Robot Learning of Haptic Interaction
Moringen A, Fleer S, Walck G, Ritter H. Attention-based Robot Learning of Haptic Interaction. In: Nisky I, Hartcher-OâBrien J, Wiertlewski M, Smeets J, eds. Haptics: Science, Technology, Applications. 12th International Conference, EuroHaptics 2020, Leiden, The Netherlands, September 6â9, 2020, Proceedings. Lecture Notes in Computer Science. Vol 12272. Cham: Springer; 2020: 462-470.Haptic interaction involved in almost any physical interaction with the environment performed by humans is a highly sophisticated and to a large extent a computationally unmodelled process. Unlike humans, who seamlessly handle a complex mixture of haptic features and profit from their integration over space and time, even the most advanced robots are strongly constrained in performing contact-rich interaction tasks. In this work we approach the described problem by demonstrating the success of our online haptic interaction learning approach on an example task: haptic identification of four unknown objects. Building upon our previous work performed with a floating haptic sensor array, here we show functionality of our approach within a fully-fledged robot simulation. To this end, we utilize the haptic attention model (HAM), a meta-controller neural network architecture trained with reinforcement learning. HAM is able to learn to optimally parameterize a sequence of so-called haptic glances, primitive actions of haptic control derived from elementary human haptic interaction. By coupling a simulated KUKA robot arm with the haptic attention model, we pursue to mimic the functionality of a finger.
Our modeling strategy allowed us to arrive at a tactile reinforcement learning architecture and characterize some of its advantages. Owing to a rudimentary experimental setting and an easy acquisition of simulated data, we believe our approach to be particularly useful for both time-efficient robot training and a flexible algorithm prototyping
Involvement of end users in the development of serious games for health care professions education : systematic descriptive review
Background:
On the basis of ethical and methodological arguments, numerous calls have been made to increase the involvement of end users in the development of serious games (SGs). Involving end users in the development process is considered a way to give them power and control over educational software that is designed for them. It can also help identify areas for improvement in the design of SGs and improve their efficacy in targeted learning outcomes. However, no recognized guidelines or frameworks exist to guide end usersâ involvement in SG development.
Objective:
The aim of this study is to describe how end users are involved in the development of SGs for health care professions education.
Methods:
We examined the literature presenting the development of 45 SGs that had reached the stage of efficacy evaluation in randomized trials. One author performed data extraction using an ad hoc form based on a design and development framework for SGs. Data were then coded and synthesized on the basis of similarities. The coding scheme was refined iteratively with the involvement of a second author. Results are presented using frequencies and percentages.
Results:
End usersâ involvement was mentioned in the development of 21 of 45 SGs. The number of end users involved ranged from 12 to 36. End users were often involved in answering specific concerns that arose during the SG design (n=6) or in testing a prototype (n=12). In many cases, researchers solicited input from end users regarding the goals to reach (n=10) or the functional esthetics of the SGs (n=7). Most researchers used self-reported questionnaires (n=7).
Conclusions:
Researchers mentioned end usersâ involvement in the development of less than half of the identified SGs, and this involvement was also poorly described. These findings represent significant limitations to evaluating the impact of the involvement of end users on the efficacy of SGs and in making recommendations regarding their involvement
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