LArGe: Background suppression using liquid argon (LAr) scintillation for 0νββ\nu\beta\beta decay search with enriched germanium (Ge) detectors

Measurements with a bare p-type high purity germanium diode (HPGe) submerged in a 19 kg liquid argon (LAr) scintillation detector at MPIK Heidelberg are reported. The liquid argon--germanium system (LArGe) is operated as a 4$\pi$ anti-Compton spectrometer to suppress backgrounds in the HPGe. This R&D is carried out in the framework of the GERDA experiment which searches for 0$\nu\beta\beta$ decays with HPGe detectors enriched in $^{76}$Ge. The goal of this work is to develop a novel method to discriminate backgrounds in 0$\nu\beta\beta$ search which would ultimately allow to investigate the effective neutrino mass free of background events down to the inverse mass hierarchy scale. Other applications in low-background counting are expected.Comment: 3 pages, 6 figures, conference proceedings of the 10th Topical Seminar on Innovative Particle and Radiation Detectors (IPRD06) 1 - 5 October 2006 Siena, Ital

Bilingualism Is Associated with a Delayed Onset of Dementia but Not with a Lower Risk of Developing it: a Systematic Review with Meta-Analyses.

Some studies have linked bilingualism with a later onset of dementia, Alzheimer's disease (AD), and mild cognitive impairment (MCI). Not all studies have observed such relationships, however. Differences in study outcomes may be due to methodological limitations and the presence of confounding factors within studies such as immigration status and level of education. We conducted the first systematic review with meta-analysis combining cross-sectional studies to explore if bilingualism might delay symptom onset and diagnosis of dementia, AD, and MCI. Primary outcomes included the age of symptom onset, the age at diagnosis of MCI or dementia, and the risk of developing MCI or dementia. A secondary outcome included the degree of disease severity at dementia diagnosis. There was no difference in the age of MCI diagnosis between monolinguals and bilinguals [mean difference: 3.2; 95% confidence intervals (CI): -3.4, 9.7]. Bilinguals vs. monolinguals reported experiencing AD symptoms 4.7 years (95% CI: 3.3, 6.1) later. Bilinguals vs. monolinguals were diagnosed with dementia 3.3 years (95% CI: 1.7, 4.9) later. Here, 95% prediction intervals showed a large dispersion of effect sizes (-1.9 to 8.5). We investigated this dispersion with a subgroup meta-analysis comparing studies that had recruited participants with dementia to studies that had recruited participants with AD on the age of dementia and AD diagnosis between mono- and bilinguals. Results showed that bilinguals vs. monolinguals were 1.9 years (95% CI: -0.9, 4.7) and 4.2 (95% CI: 2.0, 6.4) older than monolinguals at the time of dementia and AD diagnosis, respectively. The mean difference between the two subgroups was not significant. There was no significant risk reduction (odds ratio: 0.89; 95% CI: 0.68-1.16) in developing dementia among bilinguals vs. monolinguals. Also, there was no significant difference (Hedges' g = 0.05; 95% CI: -0.13, 0.24) in disease severity at dementia diagnosis between bilinguals and monolinguals, despite bilinguals being significantly older. The majority of studies had adjusted for level of education suggesting that education might not have played a role in the observed delay in dementia among bilinguals vs. monolinguals. Although findings indicated that bilingualism was on average related to a delayed onset of dementia, the magnitude of this relationship varied across different settings. This variation may be due to unexplained heterogeneity and different sources of bias in the included studies. Registration: PROSPERO CRD42015019100

Processes governing development of ecotoxicity in clayey and silty soils incubated with olive mill wast water under different temperature and humidity conditions

Olive oil production generates olive mill wastewater (OMW) with a high content in nutrients and phenolic substances. Its application to soil could be a cost-effective solution for recycling. However, the degree of toxic effects of OMW on soil biota is widely unknown and has to be considered when searching for adisposal strategy. The objective of this study was to understand the degradation process of OMW organic matter and its influence on toxic effects as well as soil properties. We hypothesized that OMW toxicity decreases with degradation of its phenolic components. A higher soil biological activity was expected to increase degradation. We incubated a clayey soil and a silty soil with OMW for 60 days under conditions typical for this region in order to simulate the application during various seasons (winter, spring, summer dry, summer wet). Soil respiration, pH, electrical conductivity, total phenolic content as well as anion and cation content, specific ultraviolet absorbance at 254 nm and dissolved organic carbon were measured at ten points of time during incubation. Soils and methanolic soil extracts were tested for ecotoxicity using Lepidium sativum germination and Folsomia candida egg hatching rate. The degradation and transformation of OMW-organic matter was stronger under warm and humid conditions than under cold and dry conditions. It was furthermore enhanced in the clayey soil compared to the silty soil. Most severe ecotoxicological effects were found under summer dry conditions while spring as well as summer wet conditions led to a fast recovery of both germination and hatching. However, the silty soil did not recover to preapplication levels. In the clayey soil, germination parameter were higher than in control after around 30 days suggesting a fertilizing effect. Effects in methanol extracts were higher in all soils and climatic scenarios. Therefore, remobilization of OMW derived toxic compounds has to be considered on a long-term scale. Egg hatching as most sensitive life-cycle parameter of Folsomia candida showed also the same relation to climatic conditions and soil type but was more robust to OMW compared to Lepidium sativum. Environmental conditions as well as soil type are key factors determining degradation of OMW organic matter and OMW derived ecotoxicity. Therefore, spring application (warm and wet) of OMW seems to be a compromise with regard to OMW recycling, OMW occurrence in winter and farmer considerations

Resurrecting Brinley Plots for a Novel Use: Meta-Analyses of Functional Brain Imaging Data in Older Adults

By plotting response times of young and older adults across a variety of tasks, Brinley spurred investigation and debate into the theory of general cognitive slowing. Though controversial, Brinley plots can assess between-task differences, the impact of increasing task demand, and the relationship between responses in two groups of subjects. Since a relationship exists between response times and the blood-oxygen level dependent (BOLD) signal of functional MRI (fMRI), Brinley's plotting method could be applied as a meta-analysis tool in fMRI studies of aging. Here, fledgling “Peiffer plots” are discussed for their potential impact on understanding general cognitive brain activity in aging. Preliminary results suggest that general cognitive slowing may be localized at the sensorimotor transformation in the precentral gyrus. Although this meta-analysis method is naturally used with imaging studies of aging, theoretically it may be applied to other study pairs (e.g., schizophrenic versus normal) or imaging datasets (e.g., PET)

Pneumothorax spontané et emphysème pulmonaire chez les consommateurs de cannabis

INTRODUCTION: If pulmonary complications of tobacco smoking are well documented, those associated with cannabis use are less known. OBJECTIVES: Systematic literature review of data on pneumothorax and lung emphysema in cannabis users. DOCUMENTARY SOURCES: Medline, on the period 1980-2018 with the following keywords cannabis or marijuana and pneumothorax or emphysema, limits "title/abstract". Among 97 articles, 42 abstracts have given use to a dual reading to select 20 studies. RESULTS: Eighteen case reports (8 with SP) showed bullae in the upper lobes in combined cannabis and tobacco smokers (CS) and in the 2 cannabis only smokers (COS). The risk of SP was increased in CS, but not in COS. In patients less than 35-years old presenting with SP, the incidence of bullae on thoracic computed tomography (CT) was higher in CS than in tobacco only smokers (TOS). CT in patients with SP showed no significant difference as regards of the prevalence, location and type of emphysema between CS and TOS. Proportion of low lung density areas was higher in CS than in non-smokers (NS), but was similar in TOS and NS. CONCLUSION: These results suggest a cumulative toxic effect of tobacco and cannabis on the risk of SP and lung emphysema

Brain weight differences associated with induced focal microgyria

BACKGROUND: Disrupting neural migration with bilateral focal freezing necrosis on postnatal day 1 (P1) results in the formation of 4-layered microgyria. This developmental injury triggers a pervasive neural reorganization, which is evident at the electrophysiological, behavioral, and anatomical levels. In this experiment, we investigated changes in brain weight as an index of global disruption of neural systems caused by focal damage to the developing cortical plate. RESULTS: We found a dramatic reduction in overall brain weight in microgyric subjects. This reduction in brain weight among animals with microgyria is reflected in decreased total brain volume, with a disproportionate decrease in neocortical volume. This effect is so robust that it is seen across varied environments, at variable ages, and across the sexes. CONCLUSIONS: This finding supports previous work suggesting that substantial reorganization of the brain is triggered by the induction of bilateral freezing damage. These results have critical implications for the profound re-organizational effects of relatively small focal injuries early in development to distributed systems throughout the brain, and particularly in the cerebral cortex

Intense physical activity is associated with cognitive performance in the elderly

Numerous studies have reported positive impacts of physical activity on cognitive function. However, the majority of these studies have utilised physical activity questionnaires or surveys, thus results may have been influenced by reporting biases. Through the objective measurement of routine levels of physical activity via actigraphy, we report a significant association between intensity, but not volume, of physical activity and cognitive functioning. A cohort of 217 participants (aged 60–89 years) wore an actigraphy unit for 7 consecutive days and underwent comprehensive neuropsychological assessment. The cohort was stratified into tertiles based on physical activity intensity. Compared with individuals in the lowest tertile of physical activity intensity, those in the highest tertile scored 9%, 9%, 6% and 21% higher on the digit span, digit symbol, Rey Complex Figure Test (RCFT) copy and Rey Figure Test 30-min recall test, respectively. Statistically, participants in the highest tertile of physical activity intensity performed significantly better on the following cognitive tasks: digit symbol, RCFT copy and verbal fluency test (all P<0.05). The results indicate that intensity rather than quantity of physical activity may be more important in the association between physical activity and cognitive function

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