Effects of Altered Prenatal Sensory Stimulation on Postnatal Contingency Learning in Bobwhite Quail Neonates (Colinus Virginianus)

Preterm infants are exposed to high levels of modified early sensory experience in the Neonatal Intensive Care Unit (NICU). Reports that preterm infants show deficits in contingency detection and learning when compared to full-term infants (Gekoski, Fagen, & Pearlman, 1984; Haley, Weinberg, & Grunau, 2006) suggest that their exposure to atypical amounts or types of sensory stimulation might contribute to deficits in these critical skills. Experimental modifications of sensory experience are severely limited with human fetuses and preterm infants, and previous studies with precocial bird embryos that develop in ovo have proven useful to assess the effects of modified perinatal sensory experience on subsequent perceptual and cognitive development. In the current study, I assessed whether increasing amounts of prenatal auditory or visual stimulation can interfere with quail neonates’ contingency detection and contingency learning in the days following hatching. Results revealed that augmented prenatal visual stimulation prior to hatching does not disrupt the ability of bobwhite chicks to recognize and prefer information learned in a contingent fashion, whereas augmented prenatal auditory stimulation disrupted the ability of chicks to benefit from contingently presented information. These results suggest that specific types of augmented prenatal stimulation that embryos receive during late prenatal period can impair the ability to learn and remember contingently presented information. These results provide testable developmental hypotheses, with the goal of improving the developmental care and management of preterm neonates in the NICU setting.

First evidence of altered sensory quality in a shellfish exposed to decreased pH relevant to ocean acidification

Understanding how seafood will be influenced by coming environmental changes such as ocean acidification is a research priority. One major gap in knowledge relates to the fact that many experiments are not considering relevant end points related directly to production (e.g., size, survival) and product quality (e.g., sensory quality) that can have important repercussions for consumers and the seafood market. The aim of this experiment was to compare the survival and sensory quality of the adult northern shrimp (Pandalus borealis) exposed for 3 wk to a temperature at the extreme of its thermal tolerance (11°C) and 2 pH treatments: pH 8.0 (the current average pH at the sampling site) and pH 7.5 (which is out of the current natural variability and relevant to near-future ocean acidification). Results show that decreased pH increased mortality significantly, by 63%. Sensory quality was assessed through semiqualitative scoring by a panel of 30 local connoisseurs. They were asked to rate 4 shrimp (2 from each pH treatment) for 3 parameters: appearance, texture and taste. Decreased pH reduced the score significantly for appearance and taste, but not texture. As a consequence, shrimp maintained in pH8.0 had a 3.4 times increased probability to be scored as the best shrimp on the plate, whereas shrimp from the pH 7.5 treatment had a 2.6 times more chance to be scored as the least desirable shrimp on the plate. These results help to prove the concept that ocean acidification can modulate sensory quality of the northern shrimp P. borealis. More research is now needed to evaluate impacts on other seafood species, socioeconomic consequences, and potential options.

Influence of diabetes on natriuretic peptide thresholds in screening for Stage B heart failure

CONTEXT: Natriuretic peptide (NP) has been shown to be an effective screening tool to identify patients with Stage B heart failure and to have clinical value in preventing heart failure progression. The impact of associated metabolic confounders on the screening utility of NP needs clarification.

OBJECTIVE: To assess the impact of diabetes mellitus (DM) on NP screening for asymptomatic Stage B heart failure.

MATERIALS AND METHODS: The study population consisted of 1368 asymptomatic patients with cardiovascular risk factors recruited from general practice as part of the STOP-HF trial. B-type NP (BNP) was quantified at point-of-care.

RESULTS: BNP was found to be as accurate for detecting Stage B heart failure in DM patients compared to non-DM patients (AUC 0.75 [0.71,0.78] and 0.77 [0.72,0.82], respectively). However, different BNP thresholds are required to achieve the same level of diagnostic sensitivity in DM compared with non-DM patients. To achieve 80% sensitivity a difference of 5-ng/L lower is required for patients with DM.

CONCLUSION: Although a significantly different BNP threshold is detected for patients with DM, the BNP concentration difference is small and unlikely to warrant a clinically different diagnostic threshold.

Impact de la cécité sur le système nociceptif

La vision joue un rôle très important dans la prévention du danger. La douleur a aussi pour fonction de prévenir les lésions corporelles. Nous avons donc testé l’hypothèse qu’une hypersensibilité à la douleur découlerait de la cécité en guise de compensation sensorielle. En effet, une littérature exhaustive indique qu’une plasticité intermodale s’opère chez les non-voyants, ce qui module à la hausse la sensibilité de leurs sens résiduels. De plus, plusieurs études montrent que la douleur peut être modulée par la vision et par une privation visuelle temporaire. Dans une première étude, nous avons mesuré les seuils de détection thermique et les seuils de douleur chez des aveugles de naissance et des voyants à l’aide d’une thermode qui permet de chauffer ou de refroidir la peau. Les participants ont aussi eu à quantifier la douleur perçue en réponse à des stimuli laser CO2 et à répondre à des questionnaires mesurant leur attitude face à des situations douloureuses de la vie quotidienne. Les résultats obtenus montrent que les aveugles congénitaux ont des seuils de douleur plus bas et des rapports de douleur plus élevés que leurs congénères voyants. De plus, les résultats psychométriques indiquent que les non-voyants sont plus attentifs à la douleur. Dans une deuxième étude, nous avons mesuré l’impact de l'expérience visuelle sur la perception de la douleur en répliquant la première étude dans un échantillon d’aveugles tardifs. Les résultats montrent que ces derniers sont en tous points similaires aux voyants quant à leur sensibilité à la douleur. Dans une troisième étude, nous avons testé les capacités de discrimination de température des aveugles congénitaux, car la détection de changements rapides de température est cruciale pour éviter les brûlures. Il s’est avéré que les aveugles de naissance ont une discrimination de température plus fine et qu’ils sont plus sensibles à la sommation spatiale de la chaleur. Dans une quatrième étude, nous avons examiné la contribution des fibres A∂ et C au traitement nociceptif des non-voyants, car ces récepteurs signalent la première et la deuxième douleur, respectivement. Nous avons observé que les aveugles congénitaux détectent plus facilement et répondent plus rapidement aux sensations générées par l’activation des fibres C. Dans une cinquième et dernière étude, nous avons sondé les changements potentiels qu’entrainerait la perte de vision dans la modulation descendante des intrants nociceptifs en mesurant les effets de l’appréhension d’un stimulus nocif sur la perception de la douleur. Les résultats montrent que, contrairement aux voyants, les aveugles congénitaux voient leur douleur exacerbée par l’incertitude face au danger, suggérant ainsi que la modulation centrale de la douleur est facilitée chez ces derniers. En gros, ces travaux indiquent que l’absence d’expérience visuelle, plutôt que la cécité, entraine une hausse de la sensibilité nociceptive, ce qui apporte une autre dimension au modèle d’intégration multi-sensorielle de la vision et de la douleur.

Functions of the SLC36 transporter Pathetic in growth control of Drosophila sensory neurons

Thesis (Ph.D.)--University of Washington, 2016-08

Sensory work of diagnosis : a crisis of legitimacy

The Janus-faced City: A Sensory History of the London Blitz 1940–1941

The city of London was, during the years of 1940–1941, a city under fire. The metropolis seemed to have two faces, like the Roman deity Janus: the face of the daylight hours, so normal, and yet so deceiving in its false quietness – and at nightfall, the city turned, and the face of it was the face of the devil himself, transforming London into a living inferno. This thesis examines the sensescapes of the Blitz, through the diaries and memoirs written of that time. The primary sources consist of seven different diaries, two autobiographies, and four research volumes that contain multiple diary- and memoire entries, mostly from the Mass Observation Archives and from the Imperial War Museum. The sensory approach is a new orientation in the field of history – it studies the five senses in their cultural contexts, interpreting the often subtle ways in which the senses affect into society, politics, culture, and class hierarchies, to name only but few. The subject of the sensory history of war is a theme widely unexamined: this thesis contributes to this frontier field by unveiling the sensorium of the London bombings, comparing the differences between the halves of nychtemeron, and examining how the Blitz was communicated by the writers as a lived, bodily experience. This study reveals the very different sensory worlds in which the Londoners lived, during a time that is often described with the mythical solidarity that was thought to exist between the people. The reality of the homeless, working class, and poor were in the foul smelling tubes, poor law -dated rations, and in the smoking ruins of East End – the contrast was massive reflecting it to the luxury hotels and restaurants of the upper classes, opportunities for evacuation, sheltering possibilities, and overall comforts of life.

Impact of Thresholds and Load Patterns when Executing HPC Applications with Cloud Elasticity

Elasticity is one of the most known capabilities related to cloud computing, being largely deployed reactively using thresholds. In this way, maximum and minimum limits are used to drive resource allocation and deallocation actions, leading to the following problem statements: How can cloud users set the threshold values to enable elasticity in their cloud applications? And what is the impact of the application’s load pattern in the elasticity? This article tries to answer these questions for iterative high performance computing applications, showing the impact of both thresholds and load patterns on application performance and resource consumption. To accomplish this, we developed a reactive and PaaS-based elasticity model called AutoElastic and employed it over a private cloud to execute a numerical integration application. Here, we are presenting an analysis of best practices and possible optimizations regarding the elasticity and HPC pair. Considering the results, we observed that the maximum threshold influences the application time more than the minimum one. We concluded that threshold values close to 100% of CPU load are directly related to a weaker reactivity, postponing resource reconfiguration when its activation in advance could be pertinent for reducing the application runtime.

The Role of Cannabinoids in the Neurobiology of Sensory Gating: A firing rate model study

Gating of sensory (e.g. auditory) information has been demonstrated as a reduction in the auditory-evoked potential responses recorded in the brain of both normal animals and human subjects. Auditory gating is perturbed in schizophrenic patients and pharmacologically by drugs such as amphetamine, phencyclidine or ketamine, which precipitate schizophrenic-like symptoms in normal subjects. The neurobiological basis underlying this sensory gating can be investigated using local field potential recordings from single electrodes. In this paper we use such technology to investigate the role of cannabinoids in sensory gating. Cannabinoids represent a fundamentally new class of retrograde messengers which are released postsynaptically and bind to presynaptic receptors. In this way they allow fine-tuning of neuronal response, and in particular can lead to so-called depolarization-induced suppression of inhibition (DSI). Our experimental results show that application of the exogenous cannabinoid WIN55, 212-2 can abolish sensory gating as measured by the amplitude of local field responses in rat hippocampal region CA3. Importantly we develop a simple firing rate population model of CA3 and show that gating is heavily dependent upon the presence of a slow inhibitory (GABAB) pathway. Moreover, a simple phenomenological model of cannabinoid dynamics underlying DSI is shown to abolish gating in a manner consistent with our experimental findings.