The mechanism and stimulation of the accommodative reflex in vertebrate eyes are reviewed. Except for lampreys, accommodation is brought about by intraocular muscles that mediate either a ...displacement or deformation of the lens, a change of the corneal radius of curvature or a combination of these mechanisms. Elasmobranchs have little accommodation and are emmetropic in water rather than hyperopic as commonly stated. Accommodation in teleosts and amphibians is well understood and achieved by lens displacement. The accommodative mechanism of amniotes is of considerable diversity and reflects different lifestyles rather than phylogenetical relationships. In all amniotes, the ciliary muscle never has a direct impact on the lens. It relaxes the tension applied to the lens by zonular fibers and/or ligaments. In birds and reptiles the ciliary muscle is usually split into two parts, of which the anterior portion changes the corneal radius of curvature. The deformation of the lens is generally achieved either by its own elasticity (humans, probably other mammals and sauropsids) or by the force of circular muscle fibers in the iris (reptiles, birds, aquatic mammals). In the second part of the paper, some of the current hypotheses about the accommodative stimulus are reviewed together with physiological response characteristics.
Currently, there is a lack of methods for simultaneous assessment of readiness for decannulation of the veno-venous (V-V) and veno-arterial (V-A) components during veno-arteriovenous (V-AV) ...extracorporal membrane oxygenation (ECMO) support. We describe a novel approach using a simultaneous off-sweep and controlled backflow test to assess readiness for decannulation from V-AV ECMO. This method needs testing in future clinical trials.
Objective
Dyspnea is a common symptom in the Emergency Department, with a wide variety of differential diagnoses. Previous research has demonstrated the diagnostic accuracy of Point-of-Care ...Ultrasound (POCUS) in this field of interest. Our goal was to better establish sonography in our emergency department with a practicable and time effective method. Therefore, we implemented a sonography protocol in an interprofessional emergency team using blended learning as a modern didactic approach and evaluated the learning and teaching success. We named the study FETUS, which stands for “Feasibility of Employing Thoracic Ultrasound in Shortness of Breath.”
Methods
A demonstration of the POCUS protocol was given, followed by individual supervision during clinical routine. A written manual, a pocket card, and further materials for personal training supplemented the training. A post-training questionnaire measured several parameters regarding the training, e.g., subjective skill-acquisition or media use.
Results
32 medical and nursing staff participated in this study, 14 of whom completed the questionnaire. All training modalities offered were well received. A pre-post comparison of subjective sonographic competence shows a significant increase in both medical and nursing staff.
The other items surveyed also indicate the success of the intervention undertaken.
Conclusion
The use of different media as a blended learning approach can support the implementation of new measures in the ongoing working routine within an interprofessional team.
An investigation of plasma-polymeric coatings on stretchable polymer films utilizing hexamethyldisiloxane and oxygen has been performed. The influence of the plasma parameters on release properties ...to polyurethane paints as well as the unpreventable transfer of traces of plasma-polymeric coatings to paints or thermosets were investigated. The elemental composition and physical properties have been analyzed using contact angle measurement and X-ray photoelectron spectroscopy (XPS) with peak fitting. The release properties of the coatings are discussed. The results show that a higher ratio of oxygen to hexamethyldisiloxane during the plasma process leads to an increase of peel forces to polyurethane paints. The XPS shows that the transfer of plasma coating to the paint is on average below 0.4 at% of silicon, which is below the critical fraction of 2 at% silicon reported in the literature. Therefore, the clear-coat paint shows no difference in its adhesion to thermosets between untreated and pretreated surfaces.
Horned lizards (
) are specialized predators, including many species that primarily feed on seed harvester ants (
). Harvester ants have strong mandibles to husk seeds or defensively bite, and a ...venomous sting. Texas horned lizards possess a blood plasma factor that neutralizes harvester ant venom and produce copious mucus in the pharynx and esophagus, thus embedding and incapacitating swallowed ants. We used high-speed video recordings to investigate complexities of their lingual prey capture and handling behavior. Lizards primarily strike ants at their mesosoma (thorax plus propodeum of abdomen). They avoid the head and gaster, even if closer to the lizard, and if prey directional movement is reversed. Orientation of captured ants during retraction is with head first (rostral), thus providing initial mucus coating of the mandibles. Prey capture accuracy and precise handling illustrates the specificity of adaptations of horned lizards in avoiding harm, and the challenges lizards face when feeding on dangerous prey.
Establishing rapport and empathy between patients and their health care provider is important but challenging in the context of a busy and crowded emergency department (ED).
We explore the hypotheses ...that rapport building, documentation, and time efficiency might be improved in the ED by providing patients a digital tool that uses Bayesian reasoning-based techniques to gather relevant symptoms and history for handover to clinicians.
A 2-phase pilot evaluation was carried out in the ED of a German tertiary referral and major trauma hospital that treats an average of 120 patients daily. Phase 1 observations guided iterative improvement of the digital tool, which was then further evaluated in phase 2. All patients who were willing and able to provide consent were invited to participate, excluding those with severe injury or illness requiring immediate treatment, with traumatic injury, incapable of completing a health assessment, and aged <18 years. Over an 18-day period with 1699 patients presenting to the ED, 815 (47.96%) were eligible based on triage level. With available recruitment staff, 135 were approached, of whom 81 (60%) were included in the study. In a mixed methods evaluation, patients entered information into the tool, accessed by clinicians through a dashboard. All users completed evaluation Likert-scale questionnaires rating the tool's performance. The feasibility of a larger trial was evaluated through rates of recruitment and questionnaire completion.
Respondents strongly endorsed the tool for facilitating conversation (61/81, 75% of patients, 57/78, 73% of physician ratings, and 10/10, 100% of nurse ratings). Most nurses judged the tool as potentially time saving, whereas most physicians only agreed for a subset of medical specialties (eg, surgery). Patients reported high usability and understood the tool's questions. The tool was recommended by most patients (63/81, 78%), in 53% (41/77) of physician ratings, and in 76% (61/80) of nurse ratings. Questionnaire completion rates were 100% (81/81) by patients and 96% (78/81 enrolled patients) by physicians.
This pilot confirmed that a larger study in the setting would be feasible. The tool has clear potential to improve patient-health care provider interaction and could also contribute to ED efficiency savings. Future research and development will extend the range of patients for whom the history-taking tool has clinical utility.
German Clinical Trials Register DRKS00024115; https://drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00024115.
To evaluate the effect of strategies to reduce the spread of simulated aerosol during chest compressions on manikin and cadaver experimental models.
To evaluate aerosol-spread we nebulized ...ultraviolet sensitive detergents into the artificial airway of a resuscitation dummy and performed CPR. The spread of the visualized aerosol was documented by a camera. In a further approach we applied nebulized detergents into the airways of human cadavers and detected the simulated spread on the same way. Among others we did recordings with undergoing compression-only-CPR, with a surgical mask or an oxygen mask on the patients face and with an inserted supraglottic airway device with and without a connected airway filter.
Most aerosol-spread at the direction of the provider was visualized during compression-only-CPR. The use of a surgical mask and of an oxygen mask on the patient's face deflected the spread. Inserting a supraglottic airway device connected to an airway filter lead to a remarkable reduction of aerosol-spread.
The early insertion of a supraglottic airway device connected to an airway filter before starting chest compression may be beneficial for staff protection during CPR.
Visual pigments, oil droplets and photoreceptor types in the retinas of four species of true chameleons have been examined by microspectrophotometry. The species occupy different photic environments: ...two species of Chamaeleo are from Madagascar and two species of Furcifer are from Africa and the Arabian Peninsula. In addition to double cones, four spectrally distinct classes of single cone were identified. No rod photoreceptors were observed. The visual pigments appear to be mixtures of rhodopsins and porphyropsins. Double cones contained a pale oil droplet in the principle member and both outer segments contained a long-wave-sensitive visual pigment with a spectral maximum between about 555 nm and 610 nm, depending on the rhodopsin/porphyropsin mixture. Long-wave-sensitive single cones contained a visual pigment spectrally identical to the double cones, but combined with a yellow oil droplet. The other three classes of single cone contained visual pigments with maxima at about 480-505, 440-450 and 375-385 nm, combined with yellow, clear and transparent oil droplets respectively. The latter two classes were sparsely distributed. The transmission of the lens and cornea of C. dilepis was measured and found to be transparent throughout the visible and near ultraviolet, with a cut off at about 350 nm.
Kidney transplantation (KT) from donors with acute kidney injury (AKI) has been associated with delayed graft function (DGF) but similar graft survival compared with KT from donors without AKI. ...Kidneys from ≥65‐year‐old donors with comorbidities are more susceptible to cold ischemia time (CIT) and DGF and it is unknown whether such elderly kidneys with AKI can also be transplanted with satisfactory outcomes.
All KTs from ≥65‐year‐old donors performed at our center from 1999 to 2019 (n = 233) were retrospectively analyzed and short‐ as well as long‐term outcomes were compared for KTs from donors with (n = 64) and without AKI (n = 169).
There were no significant differences regarding the frequency of DGF as well as the estimated glomerular filtration rate (eGFR) 1 and 3 years post‐transplant between the no‐AKI and the AKI group (DGF: no‐AKI 30.2% vs. AKI 40.6%, P = .17; eGFR at 1‐year: 31.9 ml/min/1.73 m2 vs. 35.5 ml/min/1.73 m2, P = .32; at 3‐years: 33.8 ml/min/1.73 m2 vs. 40.9 ml/min/1.73 m2, P = .18; respectively). Death‐censored graft survival and patient survival were also not significantly different. Multivariable Cox regression analysis did not identify AKI as a significant risk factor for graft loss or death.
Following careful donor and recipient selection, kidneys from ≥65‐year‐old AKI donors may potentially be transplanted with satisfactory outcomes.
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