Extremely high-potency cannabis concentrates are becoming increasingly available and popular among consumers. While prior research indicates these products are perceived to have greater detrimental ...effects relative to cannabis flower, few studies have examined their relative objective effects, and no existing studies have compared the cognitive test performance of sober flower users, concentrate users, and non-users. A total of 198 healthy adults (98 non-users, 46 exclusive flower users, and 54 concentrate users) were administered a battery of tests of memory, psychomotor speed, attention, and executive functioning under sober laboratory-controlled conditions. Significant group differences were detected on tests of verbal free recall and episodic prospective memory, with both the flower users and concentrate users demonstrating significantly worse performance than non-users. Concentrate (but not flower) users performed worse than non-users on a measure of source memory, but contrary to our hypothesis, there were no significant differences between flower and concentrate users on any of the cognitive tests. Results indicate that, under sober conditions, individuals who regularly use concentrates are no more cognitively impacted than those who exclusively use flower. These null findings may reflect the tendency for concentrate users to self-titrate and use significantly lower quantities of concentrates than flower.
Pulse shape discrimination with fast digitizers Cester, D.; Lunardon, M.; Nebbia, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2014, Letnik:
748
Journal Article
Recenzirano
The pulse shape discrimination (PSD) between neutrons and gamma rays in liquid scintillators is studied by using the charge integration method with fast digitizers having different technical ...characteristics. The use of the Figure of Merit (FoM) to verify the PSD capability is discussed. The dependence of the FoM on the digitizer sampling rate and resolution is experimentally determined. The effects due to the type of source and the irradiation geometry are also evidenced and discussed.
Gilles de la Tourette syndrome (GTS) is characterized by motor and vocal tics and often associated with obsessive–compulsive disorder (OCD). Responses to intermittent/continuous theta-burst ...stimulation (iTBS/cTBS), which probe long-term potentiation (LTP)-/depression (LTD)-like plasticity in the primary motor cortex (M1), are reduced in GTS. ITBS-/cTBS-induced M1 plasticity can be affected by brain-derived neurotrophic factor (BDNF) polymorphism. We investigated whether the BDNF polymorphism influences iTBS-/cTBS-induced LTP-/LTD-like M1 plasticity in 50 GTS patients and in 50 age- and sex-matched healthy subjects. In GTS patients, motor and psychiatric (OCD) symptom severity was rated using the Yale Global Tic Severity Scale (YGTSS) and the Yale–Brown Obsessive–Compulsive Scale (Y-BOCS). We compared M1 iTBS-/cTBS-induced plasticity in healthy subjects and in patients with GTS. We also compared responses to TBS according to BDNF polymorphism (Val/Val vs Met carriers) in patients and controls. Fourteen healthy subjects and 13 GTS patients were Met carriers. When considering the whole group of controls, as expected, iTBS increased whereas cTBS decreased MEPs. Differently, iTBS/cTBS failed to induce LTP-/LTD-like plasticity in patients with GTS. When comparing responses to TBS according to BDNF polymorphism, in healthy subjects, Met carriers showed reduced MEP changes compared with Val/Val individuals. Conversely, in patients with GTS, responses to iTBS/cTBS were comparable in Val/Val individuals and Met carriers. YGTSS and Y-BOCS scores were comparable in Met carriers and in Val/Val subjects. We conclude that iTBS and cTBS failed to induce LTP-/LTD-like plasticity in patients with GTS, and this was not affected by BDNF genotype.
The objective of this study is to clarify the role of (G4C2)n expansions in the etiology of Parkinson disease (PD) in the worldwide multicenter Genetic Epidemiology of Parkinson's Disease (GEO-PD) ...cohort.
C9orf72 (G4C2)n repeats were assessed in a GEO-PD cohort of 7,494 patients diagnosed with PD and 5,886 neurologically healthy control individuals ascertained in Europe, Asia, North America, and Australia.
A pathogenic (G4C2)n>60 expansion was detected in only 4 patients with PD (4/7,232; 0.055%), all with a positive family history of neurodegenerative dementia, amyotrophic lateral sclerosis, or atypical parkinsonism, while no carriers were detected with typical sporadic or familial PD. Meta-analysis revealed a small increase in risk of PD with an increasing number of (G4C2)n repeats; however, we could not detect a robust association between the C9orf72 (G4C2)n repeat and PD, and the population attributable risk was low.
Together, these findings indicate that expansions in C9orf72 do not have a major role in the pathogenesis of PD. Testing for C9orf72 repeat expansions should only be considered in patients with PD who have overt symptoms of frontotemporal lobar degeneration/amyotrophic lateral sclerosis or apparent family history of neurodegenerative dementia or motor neuron disease.
Inelastic nuclear interaction probability of 400 GeV/c protons interacting with bent silicon crystals was investigated, in particular for both types of crystals installed at the CERN Large Hadron ...Collider for beam collimation purposes. In comparison to amorphous scattering interaction, in planar channeling this probability is
∼
36
%
for the quasi-mosaic type (planes (111)), and
∼
27
%
for the strip type (planes (110)). Moreover, the absolute inelastic nuclear interaction probability in the axial channeling orientation, along the
⟨
110
⟩
axis, was estimated for the first time, finding a value of
0.6
%
for a crystal 2 mm long along the beam direction, with a bending angle of 55
μ
rad. This value is more than two times lower with respect to the planar channeling orientation of the same crystal, and increases with the vertical angular misalignment. Finally, the correlation between the inelastic nuclear interaction probability in the planar channeling and the silicon crystal curvature is reported.
Spatiotemporal context is an intrinsic aspect of episodic memory. Although a large literature has demonstrated that emotion enhances episodic memory, less research has considered whether and how ...emotion affects memory for the timing of an experience, despite theoretical and practical importance. In this review, we bridge three heavily researched cognitive domains - memory, emotion, and time - by discussing findings from a burgeoning literature on their intersection. We identify and review two broad ways in which memory for time has been conceptualised in the emotional memory literature, namely (1) memory for relative aspects of event timing ("when" an event detail occurred), which includes studies of temporal-order and source memory; and (2) memory for the time that elapsed during an event ("how long"), which includes studies of retrospective duration estimation. Emerging trends demonstrate that although temporal-order memory can be impaired or enhanced by emotion depending on study demands, temporal source memory, instead, is usually enhanced. Studies of duration memory show that the remembered duration of negative experiences is dilated, but it is less clear how duration memory is affected for positive events. These findings are considered under the lens of broader emotional memory literature theories, and directions for future research are proposed.
Special nuclear material detection with a mobile multi-detector system Cester, D.; Nebbia, G.; Stevanato, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2012, Letnik:
663, Številka:
1
Journal Article
Recenzirano
The detection of special nuclear material has been studied with a mobile inspection system used both as a high sensitivity passive neutron/gamma spectroscopic tool and as an active inspection device ...using tagged neutrons. The detection of plutonium samples seems to be possible with passive interrogation, even for small samples, thanks to the yield of gamma ray and neutrons. Moreover the gamma ray spectrum shows clear signatures related to
239Pu. The passive detection of uranium is much more difficult because of the low neutron yield and of the easiness of shielding the gamma ray yield of highly enriched U samples. However, we show that active interrogation with tagged neutrons is able to provide signatures for the discrimination of uranium against other heavy metals.
Background: Cannabis use is widely perceived to produce an "amotivational syndrome" characterized by reduced desire to work or compete, passivity, and lower achievement orientation. The notion that ...cannabis diminishes motivation has been perpetuated in popular culture, despite the equivocal results of past research. Moreover, previous literature has largely failed to consider the potentially confounding influences of depression, other substance use, and personality, despite known relationships between these variables and cannabis use.
Purpose: The purpose of this study was to elucidate the nature of the relationships between specific aspects of motivation and cannabis use/misuse. Moreover, we sought to determine whether depression, alcohol and other substance use, and/or personality could account for these relationships.
Method: A total of 1,168 participants completed a survey comprising self-report measures of motivation (self-efficacy, apathy, goal orientation, reward-sensitivity, and behavioral inhibition/approach systems) and cannabis use/misuse (cannabis use status, cannabis use frequency, quantity, age of onset of cannabis use, symptoms of cannabis use disorder, problematic cannabis use).
Results: The results revealed small (r < .30) but significant correlations between various aspects of cannabis use and motivation, which were largely accounted for by cannabis-related differences in depression, alcohol and other substance use, and personality. However, relationships between cannabis misuse and apathy remained statistically significant after controlling for confounds, indicating that individuals who misuse cannabis may demonstrate higher levels of apathy specifically.
Conclusion: Collectively, these results suggest that differences in depression, substance use, and personality between cannabis users and non-users largely explain differences in motivation between these groups.
This paper is devoted to an experimental study of focusing and defocusing positively charged particle beams with the help of specially bent single crystals. Four crystals have been fabricated for ...this purpose. The studies have been performed at the CERN SPS in400GeV/cproton and180GeV/cpion beams. The results of measurements of beam envelopes are presented. The rms size of the horizontal profile at the focus was 5–8 times smaller than at the exit of the crystals. The measured focal lengths were 4–21 m. The results of measurements are in good agreement with calculations. Possible applications of focusing crystals in present and future high energy accelerators are discussed.
PDF
