Differential Associations of Stress and Cortisol with Brain Structure and Cognition in Cognitively Normal Older Adults

The current literature shows discrepant findings as to the degree to which cumulative stress and dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis are associated with brain structure and cognitive function in older adults, particularly in brain regions with high expression of receptors for glucocorticoid, and cognitive function reliant upon these regions. Past studies have been heavily focused on total hippocampus while limited studies have examined hippocampal subdivisions or other brain structures. In addition, one key moderator that may influence the associations of cumulative stress and cortisol on brain structure and cognition is the single-nucleotide polymorphisms (SNPs) of the stress-system genes, which has not been investigated in older adults. Therefore, in Aim 1, the current study examined the differential associations of cumulative stress and cortisol with brain structure that have high or low expression of receptors for glucocorticoid, including total hippocampus, hippocampal subdivisions, amygdala, medial prefrontal cortex, and primary visual cortex in cognitively normal older adults. In addition, the current study examined whether the genetic score from SNPs of stress-system genes moderated these associations. Aim 2 examined the differential associations of stress and cortisol on cognitive functions, including memory, fluid intelligence, and crystallized intelligence. The moderating role of the genetic score was examined in Aim 2 as well. In general, no consistent results were found for either aim. Post-hoc analyses showed no consistent moderating role of either age or gender, but suggested timing of stress may be an important factor to consider for future studies. Overall, the current study suggests that stress and cortisol may not have robust associations with brain structure and cognition in older adults. However, future longitudinal studies with systemic incorporation of various factors, such as timing of stress and multiple cortisol measures across the day, may reveal more consistent associations of stress and cortisol

Quantile Forecasts of Daily Exchange Rate Returns from Forecasts of Realized Volatility

Quantile forecasts are central to risk management decisions because of the widespread use of Value-at-Risk. A quantile forecast is the product of two factors : the model used to forecast volatility, and the method of computing quantiles from the volatility forecasts. In this paper we calculate and evaluate quantile forecasts of the daily exchange rate returns of five currencies. The forecasting models that have been used in recent analyses of the predictability of daily realized volatility permit a comparison of the predictive power of different measures of intraday variation and intraday returns in forecasting exchange rate variability. The methods of computing quantile forecasts include making distributional assumptions for future daily returns as well as using the empirical distribution of predicted standardized returns with both rolling and recursive samples. Our main ?ndings are that the HAR model provides more accurate volatility and quantile forecasts for currencies which experience shifts in volatility, such as the Canadian dollar, and that the use of the empirical distribution to calculate quantiles can improve forecasts when there are shifts.realized volatility ; quantile forecasting ; MIDAS ; HAR ; exchange rates

Printed Receive Coils with High Acoustic Transparency for Magnetic Resonance Guided Focused Ultrasound.

In magnetic resonance guided focused ultrasound (MRgFUS) therapy sound waves are focused through the body to selectively ablate difficult to access lesions and tissues. A magnetic resonance imaging (MRI) scanner non-invasively tracks the temperature increase throughout the tissue to guide the therapy. In clinical MRI, tightly fitted hardware comprised of multichannel coil arrays are required to capture high quality images at high spatiotemporal resolution. Ablating tissue requires a clear path for acoustic energy to travel but current array materials scatter and attenuate acoustic energy. As a result coil arrays are placed outside of the transducer, clear of the beam path, compromising imaging speed, resolution, and temperature accuracy of the scan. Here we show that when coil arrays are fabricated by additive manufacturing (i.e., printing), they exhibit acoustic transparency as high as 89.5%. This allows the coils to be placed in the beam path increasing the image signal to noise ratio (SNR) five-fold in phantoms and volunteers. We also characterize printed coil materials properties over time when submerged in the water required for acoustic coupling. These arrays offer high SNR and acceleration capabilities, which can address current challenges in treating head and abdominal tumors allowing MRgFUS to give patients better outcomes

A Study of the Intellectual Structure of Community Archives

Community archives have gained renewed attention as an emerging archival movement. The goal of this study is to map the intellectual structure of community-centric archival research during the 2000-2017 period. To identify and visualize the relationships between topics within the subject areas, we analyzed the co-occurrence index and network structures of keywords derived from titles, abstracts, and author-provided keywords in peer-reviewed journal articles and conference proceedings in the field of community archives

Rumen fluke in Irish sheep: prevalence, risk factors and molecular identification of two paramphistome species

peer-reviewedBackground Rumen flukes are trematode parasites found globally; in tropical and sub-tropical climates, infection can result in paramphistomosis, which can have a deleterious impact on livestock. In Europe, rumen fluke is not regarded as a clinically significant parasite, recently however, the prevalence of rumen fluke has sharply increased and several outbreaks of clinical paramphistomosis have been reported. Gaining a better understanding of rumen fluke transmission and identification of risk factors is crucial to improve the control of this parasitic disease. In this regard, a national prevalence study of rumen fluke infection and an investigation of associated risk factors were conducted in Irish sheep flocks between November 2014 and January 2015. In addition, a molecular identification of the rumen fluke species present in Ireland was carried out using an isolation method of individual eggs from faecal material coupled with a PCR. After the DNA extraction of 54 individual eggs, the nuclear fragment ITS-2 was amplified and sequenced using the same primers. Results An apparent herd prevalence of 77.3 % was determined. Several risk factors were identified including type of pasture grazed, regional variation, and sharing of the paddocks with other livestock species. A novel relationship between the Suffolk breed and higher FEC was reported for the first time. The predominant rumen fluke species found was C. daubneyi. Nevertheless, P. leydeni was unexpectedly identified infecting sheep in Ireland for the first time. Conclusions An exceptionally high prevalence of rumen fluke among Irish sheep flocks has been highlighted in this study and a more thorough investigation is necessary to analyse its economic impact. The isolation of individual eggs coupled with the PCR technique used here has proven a reliable tool for discrimination of Paramphistomum spp. This technique may facilitate forthcoming studies of the effects of paramphistomosis on livestock production. The most noteworthy finding was the identification of P. leydeni affecting sheep in Ireland, however further studies are required to clarify its implications. Also, a significant relationship between Suffolk breed and a heavier infection was found, which can be used as a starting point for future research on control strategies of rumen fluke infection.This study was funded by Irish Department of Agriculture, Food and the Marine research stimulus funding; project reference 13/ S/405

Effect of anaerobic or/and microaerophilic atmosphere on microcosm biofilm formation and tooth demineralization

Microcosm biofilms can reproduce the complexity of a dental biofilm. However, different forms of cultivation have been used. The impact of the culture atmosphere on the development of microcosm biofilms and their potential to cause tooth demineralization has not yet been deeply studied. Objective:This study analyzes the effects of three experimental cultivation models (microaerophile vs. anaerobiosis vs. experimental mixed) on the colony-forming units (CFU) of the cariogenic microorganisms and tooth demineralization. Methodology: 90 bovine enamel and 90 dentin specimens were distributed into different atmospheres: 1) microaerophilia (5 days, 5% CO2); 2) anaerobiosis (5 days, jar); 3) mixed (2 days microaerophilia and 3 days anaerobiosis), which were treated with 0.12% chlorhexidine (positive control – CHX) or Phosphate-Buffered Saline (negative control – PBS) (n=15). Human saliva and McBain’s saliva containing 0.2% sucrose were used for microcosm biofilm formation, for 5 days. From the second day to the end of the experiment, the specimens were treated with CHX or PBS (1x1 min/day). Colony-forming units (CFU) were counted, and tooth demineralization was analyzed using transverse microradiography (TMR). Data were subjected to two-way ANOVA and Tukey’s or Sidak’s test (p<0.05). Results: CHX was able to reduce total microorganism’s CFU compared to PBS (differences of 0.3–1.48 log10 CFU/mL), except for anaerobiosis and microaerophilia in enamel and dentin biofilm, respectively. In the case of dentin, no effect of CHX on Lactobacillus spp. was observed. CHX significantly reduced enamel demineralization compared to PBS (78% and 22% reductions for enamel and dentin, respectively). Enamel mineral loss did not differ when compared with the other atmospheres; however, the enamel lesion depth was greater under anaerobiosis. Dentin mineral loss was lower under anaerobiosis when compared with the other atmospheres. Conclusion: The type of atmosphere has, in general, little influence on the cariogenic ability of the microcosm biofilm

Quelle sera l'évolution de Minergie dans ces prochaines années ?

Grâce à la prise de conscience de la population, le développement durable prend de plus en plus de place dans notre société. Néanmoins, la consommation énergétique reste un réel problème. Aussi, il en ressort qu’en Suisse 40% de la consommation énergétique et un tiers des émissions de CO2 sont dus aux bâtiments (OFEN, 2016). Des lois ont été introduites afin de pallier à ce problème et des centres de certifications ont vu le jour afin de réduire la consommation énergétique des bâtiments. L’association Minergie est la référence dans les bâtiments confortables consommant peu d’énergie. Cependant, aujourd’hui, il existe d’autres centres de certification ou normes qui permettent d’atteindre, plus au moins, les mêmes objectifs, tel que les bâtiments à haute performance énergétique (HPE). De plus, la récente mise à jour du MoPEC, et sa prochaine introduction, oblige Minergie à se mettre à jour. L’objectif de ce travail de bachelor est de connaître la future évolution de Minergie tout en prenant en compte les principales parties prenantes. Aussi, par exemple, une analyse des 5 (+1) forces de Porter ainsi qu’un SWOT ont été établis afin de prendre en compte les points essentiels. Les informations récoltées durant ces quelques mois, sur internet et grâce aux entretiens, m’ont permis d’envisager l’évolution de Minergie : réduire les écarts de performance. En effet, il arrive que la consommation réelle dépasse celle planifiée, parfois du double. Pour réduire ces écarts, il est possible de suivre diverses pistes, telles que mieux informer les locataires afin d’optimiser l’utilisation du logement. D’ailleurs, dès cette année, Minergie propose de nouveaux services afin de pallier, entre autres, aux écarts de performance

LITHIUM-AQUEOUS BATTERY

poster abstractDue to the exceptionally high energy density Lithium-water batteries have very high storage efficiency. Being able to store more energy is im-portant to many industries including electronics and electric vehicles. This is the reason that much research is being done to optimize and explore new techniques of development for these batteries. The Li-water battery has been designed in this project to test water and other aqueous solutions as the cathode. The lithium in a non-aqueous elec-trolyte acts as the anode of the battery. The solid electrolyte used in the lith-ium water batteries is a glass/ceramic (LISICON). The solid electrolyte acts as a separator allowing the Lithium ions to pass through it without allowing the liquid cathode come into direct contact the Lithium. This paper describes the creation and testing of a Lithium-water battery which uses water and Copper (II) Nitrate as the cathode electrolyte. The purpose of this paper is to compare and contrast the difference in voltage of distilled water and distilled water with Copper (II) Nitrate additives as cath-ode. When the tests were conducted, it was found that Copper (II) Nitrate does in fact increase the voltage of the Lithium-water batteries significantly when compared to the distilled water. These results were expected because of Copper (II) Nitrate’s strong electrolyte properties