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In rodents, repeated single-bottle exposures to distinctly flavored isocaloric glucose and fructose solutions, two sugars with different metabolic pathways, eventually lead to a preference for the former. Because Roux-en-Y gastric bypass (RYGB) surgery decreases preference for and intake of sugar solutions in rats, we tested whether RYGB would curtail the conditioning of a preference for a glucose-paired vs. fructose-paired flavor. RYGB (♂ n=11; ♀ n=10) and sham-operated (SHAM; ♂ n=9; ♀ n=10) rats were trained with a single bottle (30 min/day) containing 8% glucose solution flavored with either 0.05% grape or cherry Kool-Aid (Glu/CS(G)) or 8% fructose solution with the alternative Kool-Aid flavor (Fru/CS(F)) in an alternating fashion for 8 days. To determine baseline preferences, a 4-day 30-min two-bottle test was used to assess preference for Glu/CS(G) vs. Fru/CS(F) before training. After training, 2-day 30-min two-bottle tests assessed preference for the a) Glu/CS(G) (CS(G)-flavored 8% glucose solution) vs Fru/CS(F) (CS(F)-flavored 8% fructose solution), b) CS(G)- vs. CS(F)-flavored mixture of 4% glucose & 4% fructose (isocaloric), c) CS(G)- vs. CS(F)-flavored 0.2% saccharin (“sweet”, no calories), and d) CS(G)- vs. CS(F)-flavored water. During training, only male SHAM rats demonstrated progressively increased intake of Glu/CS(G) over Fru/CS(F), and female SHAM rats displayed a trend. RYGB eliminated any difference in single-bottle intake of these solutions during training, regardless of sex. Like their male and female SHAM counterparts, male RYGB rats displayed a conditioned preference for the CS(G)-associated stimulus in Tests 1-3. Although female RYGB rats displayed acquisition of the conditioned flavor preference in Test 1, unlike the other groups, when the differential sugar cue between the two solutions was removed in Tests 2 and 3, female rats did not display a CS(G) preference. When the sugar and sweetener cues were both removed on Test 4, all groups displayed some generalization decrement. Thus, RYGB does not compromise the ability of rats to learn and express a glucose- vs. fructose-associated conditioned flavor preference when the exact CS used in training is presented in testing. The mechanistic basis for the sex difference in the effect of RYGB on the generalization decrement observed in this type of flavor preference learning warrants further study.

Part of the Special Issue Health Care from Patients' Perspective, Multiple sclerosis (MS) is a chronic, inflammatory autoimmune disease of the central nervous system mainly of adults ranging from 20 to 45 years of age. The risk of developing MS is 50% higher in women than in men. Most people with MS (PwMS) experience a spectrum of symptoms such as spasticity, continence dysfunctions, fatigue, or neurobehavioral manifestations. Due to the complexity of MS and the variety of patient-centered needs, a comprehensive approach of interprofessional collaboration (IPC) of multiple health care professionals (HCP) is necessary. The aim of this qualitative study was to explore the meaning of IPC in the comprehensive care of PwMS from a HCP perspective. Focus groups (FG) with HCP were conducted, recorded, and transcribed verbatim. The sample contained HCP from three MS clinics in different phases of care and rehabilitation. Four main categories emerged: (a) experience with IPC, (b) relevant aspects for IPC in patients' treatment, (c) differences in in- and outpatient settings, and (d) influence of patient perspective. IPC plays a crucial role in the HCP perspective when treating PwMS, which can benefit from an IPC therapeutic approach because HCP work together in a patient-centered way. The inpatient setting of HCP strongly supports the implementation of IPC. This prerequisite does not exist in outpatient settings.

The differentially heated rotating annulus is a classic experiment used for the examination of circulation patterns and waves in the atmosphere. In particular, by choosing an atmosphere-like experimental setup that allows the buoyancy frequency to become larger than the Coriolis parameter, it provides a useful tool to study the generation mechanism of spontaneous gravity wave (GW) emission in jet-front systems. Recently, with the aim to gain better understanding about the conditions for the spontaneous generation of GWs, Rodda et al. (2020) compared experimental data with results from numerical simulations and found differences in the GW signal most likely due to the model's treatment of boundary conditions. The aim of the present study is to improve the consistency between the model and experiment and to investigate the effect of the lateral and upper boundary conditions on GW generation and propagation in an atmosphere-like configuration of the annulus. More precisely, we implement the corresponding lateral and surface heat fluxes, air-temperature variations, as well as evaporation at the upper boundary condition into the numerical model and examine the characteristics of the observed GW signals, which are identified by the horizontal divergence field. Our systematic analysis may serve as a basis for subsequent research on the spontaneous GW generation mechanism, following the overarching objective to develop a parameterization scheme for GWs emitted from jets and front. References:Rodda, C., S. Hien, U. Achatz, and U. Harlander, 2020: A new atmospheric-like differentially heated rotating annulus configuration to study gravity wave emission from jets and fronts. Exp. Fluids 61, 2. https://doi.org/10.1007/s00348-019-2825-z

Inertia–gravity waves (IGWs) emitted from jets and fronts are ubiquitous in the atmosphere and have a significant impact on atmospheric processes (Plougonven and Zhang, 2014). Since the mechanism responsible for the spontaneous emission of IGWs during the evolution of an initially balanced flow remain poorly understood, their representation in numerical weather prediction models is challenging (de la Cámara and Lott, 2015). Better understanding of this IGW source mechanism based on idealized numerical simulations is crucial to improve the accuracy of the forecasts. In this study, idealized baroclinic-wave life cycle experiments on the f-plane are performed to investigate spontaneous emission, using a finite-volume solver for the pseudo-incompressible equations (Rieper et al., 2013). In particular, the implementation of a semi-implicit time stepping scheme, along the lines of Smolarkiewicz and Margolin (1997) and Benaccio and Klein (2019), but adjusted to our staggered grid, permits longer simulation runs with much larger domains. A novelty is the implementation of a simple Newtonian heating function based on Held and Suarez (1994), which is used for forcing a baroclinically unstable temperature profile and allows the background state to vary in time (O’Neill and Klein, 2014). The results of the model with semi-implicit time stepping scheme will be documented and compared to an explicit Runge-Kutta scheme. The analysis may serve as a basis for the development and validation of a parameterization scheme for GWs emitted from jets and fronts. References: Benaccio, T., and R. Klein, 2019: A semi-implicit compressible model for atmospheric flows with seamless access to soundproof and hydrostatic dynamics. Mon. Wea. Rev., 147, 4221-4240.de la Cámara, A., and F. Lott, 2015: A parameterization of gravity waves emitted by fronts and jets. Geophys. Res. Lett., 42, 2071-2078.Held, I.M., and M.J. Suarez, 1994: A Proposal for the Intercomparison of the Dynamical Cores of Atmospheric General Circulation Models. Bull. Amer. Meteor. Soc., 75, 1825-1830.O’Neill, W.P., and R. Klein, 2014: A moist pseudo-incompressible model. Atmos. Res., 142, 133-141. Plougonven R., and F. Zhang, 2014: Internal gravity waves from atmospheric jets and fronts. Rev. Geophys., 52, 33-76.Rieper, F., Hickel, S., and U. Achatz, 2013: A conservative integration of the pseudo-incompressible equations with implicit turbulence parameterization. Mon. Wea. Rev., 141, 861-886. Smolarkiewicz, P.K., and L.G. Margolin, 1997: On forward-in-time differencing for fluids: an Eulerian/semi-Langrangian nonhydrostatic model for stratified flows. Atmosphere-Ocean, 35, 127- 152.

Here we systematically tested the hypothesis that motivated behavioral responsiveness to preferred and avoided taste compounds is relatively independent of the olfactory system in mice whose olfactory bulbs (main and accessory) were surgically disconnected from the rest of the brain [bulbotomy (BULBx)]. BULBx was confirmed histologically as well as functionally with the buried food test. In brief access taste tests, animals received 10-s trials of various concentrations of a taste compound delivered quasirandomly. BULBx C57BL/6 (B6) mice displayed severely blunted concentration-dependent licking for the disaccharide sucrose, the maltodextrin Maltrin, and the fat emulsion Intralipid relative to their sham-operated controls (SHAM B6). Licking for the noncaloric sweetener saccharin was also blunted by bulbotomy, but less so. As expected, mice lacking a functional “sweet” receptor [T1R2+T1R3 knockout (KO)] displayed concentration-dependent responsiveness to Maltrin and severely attenuated licking to sucrose. Like in B6 mice, responsiveness to both stimuli was exceptionally curtailed by bulbotomy. In contrast to these deficits in taste-guided behavior for unconditionally preferred stimuli, BULBx in B6 and KO mice did not alter concentration-dependent decreases for the representative avoided stimuli quinine and citric acid. Nor did it temper the intake of and preference for high concentrations of affectively positive stimuli when presented in long-term (23-h) two-bottle tests, demonstrating that the surgery does not lead to a generalized motivational deficit. Collectively, these behavioral results demonstrate that specific aspects of taste-guided ingestive motivation are profoundly disturbed by eliminating the anatomic connections between the main/accessory olfactory bulbs and the rest of the brain.