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We measure the thermophoresis of polysterene beads over a wide range of temperature gradients and find a pronounced nonlinear phoretic characteristic. The transition to the nonlinear behavior is marked by a drastic slowing down of thermophoretic motion and is characterized by a Péclet number of order unity as corroborated for different particle sizes and salt concentrations. The data follow a single master curve covering the entire nonlinear regime for all system parameters upon proper rescaling of the temperature gradients with the Péclet number. For low thermal gradients, the thermal drift velocity follows a theoretical linear model relying on the local-equilibrium assumption, while linear theoretical approaches based on hydrodynamic stresses, ignoring fluctuations, predict significantly slower thermophoretic motion for steeper thermal gradients. Our findings suggest that thermophoresis is fluctuation dominated for small gradients and crosses over to a drift-dominated regime for larger Péclet numbers in striking contrast to electrophoresis.

We calculate the thermophoretic drift of a charged single colloidal particle with hydrodynamically slipping surface immersed in an electrolyte solution in response to a small temperature gradient. Here we rely on a linearized hydrodynamic approach for the fluid flow and the motion of the electrolyte ions while keeping the full nonlinearity of the Poisson-Boltzmann equation of the unperturbed system to account for possible large surface charging. The partial differential equations are transformed into a coupled set of ordinary differential equations in linear response. Numerical solutions are elaborated for parameter regimes of small and large Debye shielding and different hydrodynamic boundary conditions encoded in a varying slip length. Our results are in good agreement with predictions from recent theoretical work and successfully describe experimental observations on thermophoresis of DNA. We also compare our numerical results with experimental data on polystyrene beads.

We study the two-dimensional motion of colloidal dimers by single-particle tracking and compare the experimental observations obtained by bright-field microscopy to theoretical predictions for anisotropic diffusion. The comparison is based on the mean-square displacements in the laboratory and particle frame as well as generalizations of the self-intermediate scattering functions, which provide insights into the rotational dynamics of the dimer. The diffusional anisotropy leads to a measurable translational-rotational coupling that becomes most prominent by aligning the coordinate system with the initial orientation of the particles. In particular, we find a splitting of the time-dependent diffusion coefficients parallel and perpendicular to the long axis of the dimer which decays over the orientational relaxation time. Deviations of the self-intermediate scattering functions from pure exponential relaxation are small but can be resolved experimentally. The theoretical predictions and experimental results agree quantitatively.

Background: Effective patient- and family-centered care requires a dedication to engaging patients and family members in health system redesign to improve the quality, safety, and experience of care. Provided here are lessons learned six years after establishing an infrastructure of patient and family advisory councils (PFACs) focused on improving health care quality and safety., Context: A large regional health care system with multiple hospitals and ambulatory care delivery sites in the eastern United States adopted a systemwide approach to Patient and Family Advisory Councils on Quality and Safety (PFACQS Ⓡ ) in 2012., Approach: This conceptual article describes the barriers and facilitators of adopting, implementing, and sustaining the PFACQS model across a large, geographically diffuse health system. Successful strategies that emerged include active board engagement, co-creation and mentorship by experienced patient advocates to support enhanced engagement by local PFACQS community members, and clear alignment with and line of sight on organizational quality and safety goals., Conclusion: Implementing a robust network of PFACQS focused on improving quality and patient safety requires leadership commitment to transparency, as well as mutual respect and trust. Establishing clear guidelines, structures, and processes supports early adoption. Openness to continuous improvement and adaptations are important to program success and contribute to program sustainability., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

A key event in human evolution is the expansion of modern humans of African origin across Eurasia between 60 and 40 thousand years (kyr) before present (bp), replacing all other forms of hominins. Owing to the scarcity of human fossils from this period, these ancestors of all present-day non-African modern populations remain largely enigmatic. Here we describe a partial calvaria, recently discovered at Manot Cave (Western Galilee, Israel) and dated to 54.7 ± 5.5 kyr bp (arithmetic mean ± 2 standard deviations) by uranium-thorium dating, that sheds light on this crucial event. The overall shape and discrete morphological features of the Manot 1 calvaria demonstrate that this partial skull is unequivocally modern. It is similar in shape to recent African skulls as well as to European skulls from the Upper Palaeolithic period, but different from most other early anatomically modern humans in the Levant. This suggests that the Manot people could be closely related to the first modern humans who later successfully colonized Europe. Thus, the anatomical features used to support the 'assimilation model' in Europe might not have been inherited from European Neanderthals, but rather from earlier Levantine populations. Moreover, at present, Manot 1 is the only modern human specimen to provide evidence that during the Middle to Upper Palaeolithic interface, both modern humans and Neanderthals contemporaneously inhabited the southern Levant, close in time to the likely interbreeding event with Neanderthals.

Background: Despite the acknowledgment that error disclosure is essential to patient safety and the patient-provider relationship, there is little undergraduate training related to error disclosure., Description: Pilot test and evaluate an educational module designed to improve student confidence in understanding and performing medical error disclosure. The training was designed to establish competency in the four Rs of apology-recognition, responsibility, regret, and remedy-and included a 3-hr interactive discussion, training DVDs, practice of full disclosure using standardized patients, and facilitated reflection. Students were assessed pre and post using a self-administered confidence survey., Evaluations: Confidence among students improved significantly from 11.5 +/- 2.9 before to 15.3 +/- 1.3 after the module (p <.0001)., Conclusions: The full disclosure educational module significantly improved students' perceived confidence in admitting medical errors and their confidence in understanding and performing the full disclosure of a medical error.

Unlabelled: Despite mounting clinical evidence that supports its safety, the question of the potential adverse effects of sevoflurane on renal function continues to generate some controversy. This study retrospectively evaluated pooled renal laboratory data from 22 different clinical trials that compared sevoflurane with three widely used anesthetics. The trials examined postoperative changes in serum creatinine and blood urea nitrogen levels from a total of 3, 436 ASA physical status I-IV adult surgical patients administered either sevoflurane (n = 1941) or a control drug (isoflurane, enflurane, or propofol; n = 1495) as the maintenance anesthetic. The incidences of increased serum creatinine and blood urea nitrogen concentrations were similar among patients administered sevoflurane and those administered control drugs. Additionally, no trends specific to sevoflurane were observed with respect to postoperative serum creatinine concentration and fresh gas flow rate, concurrent treatment with nephrotoxic antibiotics, or type of carbon dioxide absorbent., Implications: Our data for changes in serum creatinine and blood urea nitrogen indicate that, for exposures of less than 4 minimum alveolar anesthetic concentration/h, sevoflurane is not associated with an increased risk of renal toxicity compared with other commonly used anesthetics. For clinical purposes, the pre- to postoperative changes in serum creatinine and blood urea nitrogen are appropriate measures of renal function in surgical patients.

The effects of MgSO4 or MgCl2 infusion on the duration of epinephrine-induced cardiac arrhythmia were evaluated in male rats anesthetized with either halothane or pentobarbital. In addition, the duration of epinephrine-induced arrhythmia in pentobarbital (50 mg/kg) anesthetized rats was compared with the duration of arrhythmia in halothane (1.5%) anesthetized rats. During halothane anesthesia MgSO4 or MgCl2 infused at a dose rate of 8 mg.kg-1.min-1 for 20 min caused a significant reduction in the duration of arrhythmia (100% and 80%, respectively) following a 4-microgram/kg injection of epinephrine and a significant threefold reduction in arrhythmia duration for each salt following an 8- or 16-micrograms/kg injection of epinephrine. Significantly shorter periods of arrhythmia after each dose of epinephrine were seen in rats anesthetized with pentobarbital than were seen in rats anesthetized with halothane. No significant difference was seen between MgSO4 or MgCl2 infusions in any of these studies. Twenty-minute infusions of MgSO4 (8 mg.kg-1.min-1) were compared with propranolol (0.03 mg.kg-1.min-1) and verapamil (0.5 micrograms.kg-1.min-1) infusions on the duration of arrhythmia after epinephrine (8 micrograms/kg) injections in halothane anesthetized rats. MgSO4 and propranolol infusion caused a significant reduction in the duration of arrhythmia (81% and 70%, respectively). Verapamil infusion caused only a 48% reduction in arrhythmia duration. While there was no significant difference between MgSO4 or propranolol, both caused a significantly greater reduction in arrhythmia than verapamil. CaCl2 (0.15 mM.kg-1.min-1) infusion for 5 min caused a significant fivefold increase in the duration of arrhythmia during halothane anesthesia.(ABSTRACT TRUNCATED AT 250 WORDS)