Applying the Evidence: Taste Manipulation as a Dysphagia Management Strategy

Purpose: This narrative review aims to summarize the evidence regarding taste manipulation as a dysphagia management strategy within the evidence-based practice framework, with a focus on clinical application for speech-language pathologists. Method: First, we present background information on the physiology of taste and swallowing. A summary of research evidence on the effect of taste on swallowing is presented, followed by suggested methods for incorporating taste into swallowing evaluation and intervention. An overview of individual factors that can impact taste perception is provided. Finally, we discuss methods of clinical application and future directions for clinicians. Conclusions: Although taste manipulation has received increased attention in the research literature, further research is needed to clarify its interaction with swallowing, particularly given the multisensory nature of eating and individual factors that mediate taste perception. Much of the existing evidence is based on participants without dysphagia; additional clinical research is needed on taste manipulation in persons with dysphagia. Clinicians can incorporate taste in their evaluation of swallowing and treatment and consider how individual taste perception and preferences impact dysphagia management

The Effect of Genetic Taste Status on Swallowing: A Literature Review

Purpose Swallowing and taste share innervation pathways and are crucial to nutritive intake. Individuals vary in their perception of taste due to factors such as genetics; however, it is unclear to what extent genetic taste status influences swallowing physiology and function. The purpose of this review article is to provide background on genetic taste status, review the evidence on the association between genetic taste status and swallowing, and discuss research and clinical implications. Method A comprehensive literature review was conducted using search terms related to swallowing and genetic taste status. Studies were included if they investigated the main effect of genetic taste status on swallowing or the interaction of genetic taste status with other variables. Studies were grouped by participant population (healthy participants or persons with a swallowing disorder), swallowing-related outcome measure, and method of genetic taste status measurement. Results The results were mixed, with five of 10 reviewed studies reporting a statistically significant main or interaction effect on swallowing. Most studies included healthy participants, with only one study investigating participants with dysphagia. Additionally, swallowing-related outcome measures and methods of determining genetic taste status varied greatly between studies conducted on separate cohorts. Conclusion Few studies have incorporated genetic taste status as a variable in swallowing research, and results are mixed. Future research on sensation and swallowing should consider the potential effect of genetic taste status and follow standardized procedures for its determination. Despite the limited evidence, clinicians may consider how individual differences in perception shape swallowing outcomes

Very slow erosion rates and landscape preservation across the southwestern slope of the Ladakh Range, India

Erosion rates are key to quantifying the timescales over which different topographic and geomorphic domains develop in mountain landscapes. Geomorphic and terrestrial cosmogenic nuclide (TCN) methods were used to determine erosion rates of the arid, tectonically quiescent Ladakh Range, northern India. Five different geomorphic domains are identified and erosion rates are determined for three of the domains using TCN 10Be concentrations. Along the range divide between 5600 and 5700 m above sea level (asl), bedrock tors in the periglacial domain are eroding at 5.0 ± 0.5 to 13.1 ± 1.2 meters per million years (m/m.y.)., principally by frost shattering. At lower elevation in the unglaciated domain, erosion rates for tributary catchments vary between 0.8 ± 0.1 and 2.0 ± 0.3 m/m.y. Bedrock along interfluvial ridge crests between 3900 and 5100 m asl that separate these tributary catchments yield erosion rates <0.7 ± 0.1 m/m.y. and the dominant form of bedrock erosion is chemical weathering and grusification. Erosion rates are fastest where glaciers conditioned hillslopes above 5100 m asl by over‐steepening slopes and glacial debris is being evacuated by the fluvial network. For range divide tors, the long‐term duration of the erosion rate is considered to be 40–120 ky. By evaluating measured 10Be concentrations in tors along a model 10Be production curve, an average of ~24 cm is lost instantaneously every ~40 ky. Small (<4 km2) unglaciated tributary catchments and their interfluve bedrock have received very little precipitation since ~300 ka and the long‐term duration of their erosion rates is 300–750 ky and >850 ky, respectively. These results highlight the persistence of very slow erosion in different geomorphic domains across the southwestern slope of the Ladakh Range, which on the scale of the orogen records spatial changes in the locus of deformation and the development of an orogenic rain shadow north of the Greater Himalaya. Copyright © 2014 John Wiley & Sons, Ltd

Education is not a panacea for reducing human–black bear conflicts

The long-term survival of carnivores is greatly challenged by conflict with humans. Such conflicts can bolster risk perceptions,lower tolerance, and lead to support of lethal control of carnivores.To address this ubiquitous challenge and improve conservation outcomes specifically for American black bears (Ursus americanus),Marley et al. (2017) used an agent based model to explore how management strategies could alter the use of the urban environment by bears, and subsequently reduce the occurrence of human-bear conflicts. Management strategies entailed education only, where people were taught to remove food attractants, apply aversive conditioning, or both, and the authors considered different spatial configurations of implementation (border, clustered, and random). Education resulting in food removals led to a reduction in the food values of urban cells. Education resulting in aversive conditioning led to increased vigilance by humans and increased probability of a bear being deterred, which in turn, resulted in the bear moving a significant distance away from the urban cell as well as a reduced memory value for those cells. Food and memory cell values deter-mined the movement choices of the bears in the next time step, and cell visits along with the occurrence of deterrence events deter-mined the habituation and food conditioning status of bears. When bears reached thresholds determined by the authors, they changed their status from ‘graduated’ to ‘survival’ and eventually ‘conflict’ status, which was modeled as a function of independent variables including initialization conditions (e.g., percent urbanization; Table5 of Marley et al., 2017) and management strategies (e.g., clustered vigilance; Fig. 5 of Marley et al., 2017). The authors concluded that,compared to a ‘no teaching’ scenario, education works to reduce‘conflict’ bears in urban areas, and that teaching people to apply aversive conditioning was the most effective strategy

Study of multilayer-reflected beam profiles and their coherence properties using beamlines ID19 (ESRF) and 32-ID (APS)

Abstract. The use of multilayer mirrors is an interesting alternative for reflective X-ray monochromatization with respect to reflection from crystal optics. The increased photon flux density due to the multilayers' larger bandwidth is of crucial importance for, e.g, full-field X-ray imaging applications. Drawbacks are the introduced modifications of the reflected beam profile as well as a certain loss of coherence, summarized as wavefront degradation. Our recent work has shown that the modification of the beam profile can vary with, e.g., the material composition of the coating applied. In order to verify our findings, a beamline round-robin has been initiated, comparing the wavefront profiles after reflection by selected multilayers at beamlines 32-ID (Advanced Photon Source) and ID19 (European Synchrotron Radiation Facility) with our initial results acquired at BM05 (ESRF

Effect of Nanoparticle Size on the Morphology of Adsorbed Surfactant Layers

The surface aggregates structure of dimethyldodecylamine-N-oxide (C12DAO) in three silica dispersions of different particle sizes (16 - 42 nm) was studied by small-angle neutron scattering (SANS) in a H2O/D2O solvent mixture matching the silica. At the experimental conditions (pH 9) the surfactant exists in its nonionic form and the structure of the adsorbed layer is not affected by added electrolyte. It is found that C12DAO forms spherical surface micelles of 2 nm diameter on the 16 nm silica particles, but oblate ellipsoidal surface micelles are formed on the 27 and 42 nm particles. The dimensions of these oblate surface aggregates (minor and major semi-axes Rn and Rlat) are similar to those of C12DAO micelles in the aqueous solutions. It is concluded that the morphological transition from spherical to ellipsoidal surface aggregates is induced by the surface curvature of the silica particles. A comparison of the shape and dimensions of the surface aggregates formed by C12DAO and C12E5 on the 16 nm silica particles demonstrates that the nature of the surfactant head group does not determine the morphology of the surface aggregates, but has a strong influence on the number of surface aggregates per particle, due to the different interactions of the head groups with the silica surface