646 research outputs found
Implementation of Nonlinear Model Predictive Path-Following Control for an Industrial Robot
Many robotic applications, such as milling, gluing, or high precision
measurements, require the exact following of a pre-defined geometric path. In
this paper, we investigate the real-time feasible implementation of model
predictive path-following control for an industrial robot. We consider
constrained output path following with and without reference speed assignment.
We present results from an implementation of the proposed model predictive
path-following controller on a KUKA LWR IV robot.Comment: 8 pages, 3 figures; final revised versio
The use of digital tablets eases the way to compassionate care during the COVID-19 pandemic
Objective: A patient communication program was implemented as a response to hospitals visiting restrictive policies during the COVID-19 pandemic. The aim of the program was to facilitate communication between patients and families, mainly through the use of digital tablets; thus program performance was evaluated by selecting the number of calls performed, the average call time, and the percentage of patients that used the program more than once.
Methods: A communication service for hospitalized patients who did not have access to a personal electronic device or were unable to use their electronic device was launched at different MUHC hospitals. A dedicated team of re-deployed employees was available to help patients connect with their loved ones using a hospital tablet or telephone.
Results: A total of 806 calls were performed between April and November 2020. Eighty one percent of the calls were performed during the non-visitors policy implementation, being video calls preferred over phone calls. The average call time was 15 min, 34% of the patients had a video call with their loved one more than once and 40% of the calls were performed in the intensive care unit.
Conclusion: The patient communication program can be described as a new delivery model of compassionate care. It was effective, helped reduce patients’ isolation and met the needs of family members and caregivers during the hospital non-visitors policy directed by the Ministère de la Santé et des Services Sociaux de Québec during the Covid-19 pandemic.
 
Self-Assembled Fluorescent Block Copolymer Micelles with Responsive Emission
Responsive fluorescent materials offer a high potential for sensing and (bio‐)imaging applications. To investigate new concepts for such materials and to broaden their applicability, the previously reported non‐fluorescent zinc(II) complex [Zn(L)] that shows coordination‐induced turn‐on emission was encapsulated into a family of non‐fluorescent polystyrene‐block‐poly(4‐vinylpyridine) (PS‐b‐P4VP) diblock copolymer micelles leading to brightly emissive materials. Coordination‐induced turn‐on emission upon incorporation and ligation of the [Zn(L)] in the P4VP core outperform parent [Zn(L)] in pyridine solution with respect to lifetimes, quantum yields, and temperature resistance. The quantum yield can be easily tuned by tailoring the selectivity of the employed solvent or solvent mixture and, thus, the tendency of the PS‐b‐P4VP diblock copolymers to self‐assemble into micelles. A medium‐dependent off–on sensor upon micelle formation could be established by suppression of non‐micelle‐borne emission background pertinent to chloroform through controlled acidification indicating an additional pH‐dependent process
Pathogenicity of Highly Pathogenic Avian Influenza Virus (H5N1) in Adult Mute Swans
Adult, healthy mute swans were experimentally infected with highly pathogenic avian influenza virus A/Cygnus cygnus/Germany/R65/2006 subtype H5N1. Immunologically naive birds died, whereas animals with preexisting, naturally acquired avian influenza virus–specific antibodies became infected asymptomatically and shed virus. Adult mute swans are highly susceptible, excrete virus, and can be clinically protected by preexposure immunity
Experimental Infection of Cattle with Highly Pathogenic Avian Influenza Virus (H5N1)
Four calves were experimentally inoculated with highly pathogenic avian influenza virus A/cat/Germany/R606/2006 (H5N1) isolated from a cat in 2006. All calves remained healthy, but several animals shed low amounts of virus, detected by inoculation of nasal swab fluid into embryonated chicken eggs and onto MDCK cells. All calves seroconverted
Magnetic NiFe₂O₄ Nanoparticles Prepared via Non-Aqueous Microwave-Assisted Synthesis for Application in Electrocatalytic Water Oxidation
Phase‐pure spinel‐type magnetic nickel ferrite (NiFe(2)O(4)) nanocrystals in the size range of 4 to 11 nm were successfully synthesized by a fast and energy‐saving microwave‐assisted approach. Size and accessible surface areas can be tuned precisely by the reaction parameters. Our results highlight the correlation between size, degree of inversion, and magnetic characteristics of NiFe(2)O(4) nanoparticles, which enables fine‐tuning of these parameters for a particular application without changing the elemental composition. Moreover, the application potential of the synthesized powders for the electrocatalytic oxygen evolution reaction in alkaline media was demonstrated, showing that a low degree of inversion is beneficial for the overall performance. The most active sample reaches an overpotential of 380 mV for water oxidation at 10 mA cm(−2) and 38.8 mA cm(−2) at 1.7 V vs. RHE, combined with a low Tafel slope of 63 mV dec(−1)
No signs of check-list fatigue - introducing the StOP? intra-operative briefing enhances the quality of an established pre-operative briefing in a pre-post intervention study.
The team timeout (TTO) is a safety checklist to be performed by the surgical team prior to incision. Exchange of critical information is, however, important not only before but also during an operation and members of surgical teams frequently feel insufficiently informed by the operating surgeon about the ongoing procedure. To improve the exchange of critical information during surgery, the StOP?-protocol was developed: At appropriate moments during the procedure, the leading surgeon briefly interrupts the operation and informs the team about the current Status (St) and next steps/objectives (O) of the operation, as well as possible Problems (P), and encourages questions of other team members (?). The StOP?-protocol draws attention to the team. Anticipating the occurrence of StOP?-protocols may support awareness of team processes and quality issues from the beginning and thus support other interventions such as the TTO; however, it also may signal an additional demand and contribute to a phenomenon akin to "checklist fatigue." We investigated if, and how, the introduction of the StOP?-protocol influenced TTO quality.
This was a prospective intervention study employing a pre-post design. In the visceral surgical departments of two university hospitals and one urban hospital the quality of 356 timeouts (out of 371 included operation) was assessed by external observers before (154) and after (202) the introduction of the StOP?-briefing. Timeout quality was rated in terms of timeout completeness (number of checklist items mentioned) and timeout quality (engagement, pace, social atmosphere, noise).
As compared to the baseline, after the implementation of the StOP?-protocol, observed timeouts had higher completeness ratings (F = 8.69, p = 0.003) and were rated by observers as higher in engagement (F = 13.48, p < 0.001), less rushed (F = 14.85, p < 0.001), in a better social atmosphere (F = 5.83, p < 0.016) and less noisy (F = 5.35, p < 0.022).
Aspects of TTO are affected by the anticipation of StOP?-protocols. However, rather than harming the timeout goals by inducing "checklist fatigue," it increases completeness and quality of the team timeout
Monte Carlo simulation of a two-dimensional continuum Coulomb gas
We study the classical two-dimensional Coulomb gas model for thermal vortex
fluctuations in thin superconducting/superfluid films by Monte Carlo simulation
of a grand canonical vortex ensemble defined on a continuum. The
Kosterlitz-Thouless transition is well understood at low vortex density, but at
high vortex density the nature of the phase diagram and of the vortex phase
transition is less clear. From our Monte Carlo data we construct phase diagrams
for the 2D Coulomb gas without any restrictions on the vortex density. For
negative vortex chemical potential (positive vortex core energy) we always find
a Kosterlitz-Thouless transition. Only if the Coulomb interaction is
supplemented with a short-distance repulsion, a first order transition line is
found, above some positive value of the vortex chemical potential.Comment: 10 pages RevTeX, 7 postscript figures included using eps
Manipulating photorespiration to increase plant productivity:recent advances and perspectives for crop improvement
Recycling of the 2-phosphoglycolate generated by the oxygenase reaction of Rubisco requires a complex and energy-consuming set of reactions collectively known as the photorespiratory cycle. Several approaches aimed at reducing the rates of photorespiratory energy or carbon loss have been proposed, based either on screening for natural variation or by means of genetic engineering. Recent work indicates that plant yield can be substantially improved by the alteration of photorespiratory fluxes or by engineering artificial bypasses to photorespiration. However, there is also evidence indicating that, under certain environmental and/or nutritional conditions, reduced photorespiratory capacity may be detrimental to plant performance. Here we summarize recent advances obtained in photorespiratory engineering and discuss prospects for these advances to be transferred to major crops to help address the globally increasing demand for food and biomass production
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