Long-lived radon daughters are a critical background source in experiments searching for low-energy rare events. Originating from radon in ambient air, radioactive polonium, bismuth and lead isotopes ...plate-out on materials that are later employed in the experiment. In this paper, we examine cleaning procedures for their capability to remove radon daughters from PTFE surfaces, a material often used in liquid xenon TPCs. We find a large difference between the removal efficiency obtained for the decay chains of
222
Rn and
220
Rn. This indicates that the plate-out mechanism has an effect on the cleaning success. While the long-lived
222
Rn daughters can be reduced by a factor of 2, the removal of
220
Rn daughters is up to 10 times more efficient depending on the treatment. Furthermore, the impact of a nitric acid based PTFE cleaning on the liquid xenon purity is investigated in a small-scale liquid xenon TPC.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A
bstract
The
Neutrino Experiment with a Xenon TPC
(NEXT) searches for the neutrinoless double-beta (0
νββ
) decay of
136
Xe using high-pressure xenon gas TPCs with electroluminescent amplification. ...A scaled-up version of this technology with about 1 tonne of enriched xenon could reach in less than 5 years of operation a sensitivity to the half-life of 0
νββ
decay better than 10
27
years, improving the current limits by at least one order of magnitude. This prediction is based on a well-understood background model dominated by radiogenic sources. The detector concept presented here represents a first step on a compelling path towards sensitivity to the parameter space defined by the inverted ordering of neutrino masses, and beyond.
A
bstract
Convolutional neural networks (CNNs) are widely used state-of-the-art computer vision tools that are becoming increasingly popular in high-energy physics. In this paper, we attempt to ...understand the potential of CNNs for event classification in the NEXT experiment, which will search for neutrinoless double-beta decay in
136
Xe. To do so, we demonstrate the usage of CNNs for the identification of electron-positron pair production events, which exhibit a topology similar to that of a neutrinoless double-beta decay event. These events were produced in the NEXT-White high-pressure xenon TPC using 2.6 MeV gamma rays from a
228
Th calibration source. We train a network on Monte Carlo-simulated events and show that, by applying on-the-fly data augmentation, the network can be made robust against differences between simulation and data. The use of CNNs offers significant improvement in signal efficiency and background rejection when compared to previous non-CNN-based analyses.
Objective: Several diagnostic methods have been used in the identification of mechanical properties of skeletal muscle, including myofascial trigger points (MTrPs), however, they are not suitable for ...daily clinical use. Myotonometry offers an easy noninvasive alternative to assess these muscle properties. Nevertheless, previous research has not yet studied the mechanical properties of MTrPs by myotonometry. The purposes of this study were (1) to analyze the differences in the mechanical properties between latent MTrPs and their taut bands by myotonometry, (2) to investigate the inter-rater reproducibility of myotonometric measurements, and (3) to examine the association between myotonometry and passive isokinetic dynamometry. Approach: Fifty individuals (58% male; age 24.6 ± 7.9 years) with a latent medial MTrP of the right soleus muscle participated. The mechanical properties of this MTrP area of soleus muscle and its taut band area were measured using a myotonometer (MyotonPRO). Additionally, passive resistive torque and extensibility of triceps surae muscle were assessed using a Kin-Com dynamometer. Main results: Statistical analysis indicated higher values for the stiffness parameter in the taut band with respect to the MTrP (P < 0.05). The inter-rater reliability of the myotonometric measurements was good for all variables (ICC3,1 > 0.75). The standard error of measurement (SEM) and minimal detectable difference (MDD) indicated a small measurement error for frequency and stiffness variables (SEM% < 10%; MDD95% < 20%). Significant fair correlations between myotonometric parameters and passive isokinetic parameters ranged from −0.29 to 0.48 (P < 0.05). Significance: The myotonometer was demonstrated to be a reliable tool and was able to quantify differences in the mechanical properties of myofascial tissues. The potential of this method for the assessment of myofascial pain syndromes requires further investigation.
IntroductionPsychotic disorders have a huge impact on social functioning, which is the ability to stablish and maintain social activities such as interpersonal relationships and self-care activities ...of daily living. Research data support that the early intervention in people who have experienced a first episode of psychosis (FEP) -based on a multidisciplinary treatment including both psychopharmacological and psychosocial treatments-, has a relevant role in a favorable evolution. AGES-Mind study is based on manualized psychotherapeutic interventions for people with first-psychosis episodes.ObjectivesTo describe the use of rehabilitation resources and social functioning in a group of people with FEP who were included in a psychotherapeutic group program versus a control group, at 12 and 24 months since the beginning of the intervention.MethodsLongitudinal, analytical, observational, retrospective study on a cohort of 46 patients with first-episode psychosis within the last 5 years. 23 patients received group psychotherapy in the context of the AGES-Mind study and they were compared with 23 control patients who did not receive a group intervention (treatment as usual). Controls were matched by age, gender and time elapsed since the first episode of psychosis with those exposed to the intervention. Sociodemographic data, social functioning (self-care, social activities, social relationships, and behavior) and use of rehabilitation resources outcome variables were assessed.ResultsSignificant differences were found regarding participation in social activities in the intervention group versus control group at 24 months. No significant differences were found in other dimensions of social functioning or in the use of rehabilitation resources.Image:Image 2:ConclusionsFurther studies with larger sample sizes are needed in order to determine if the participation in group therapy leads to an improvement in social functioning and use of rehabilitation resources for people who have experienced a first episode of psychosis.Disclosure of InterestNone Declared
Absence of dc-conductivity in lambda-DNA de Pablo, P J; Moreno-Herrero, F; Colchero, J ...
Physical review letters,
12/2000, Letnik:
85, Številka:
23
Journal Article
Recenzirano
The electrical conductivity of biomaterials on a molecular scale is of fundamental interest in the life sciences. We perform first principles electronic structure calculations, which clearly indicate ...that lambda-DNA chains should present large resistance values. We also present two direct procedures to measure electrical currents through DNA molecules adsorbed on mica. The lower limit for the resistivity is 10(6) Omega . cm, in agreement with our calculations. We also show that low energy electron bombardment induces a rapid contamination and dramatically affects the measured conductivity, thus providing an explanation to recent reports of high DNA conductivity.
A
bstract
Natural radioactivity represents one of the main backgrounds in the search for neutrinoless double beta decay. Within the NEXT physics program, the radioactivity- induced backgrounds are ...measured with the NEXT-White detector. Data from 37.9 days of low-background operations at the Laboratorio Subterráneo de Canfranc with xenon depleted in
136
Xe are analyzed to derive a total background rate of (0.84
±
0.02) mHz above 1000 keV. The comparison of data samples with and without the use of the radon abatement system demonstrates that the contribution of airborne-Rn is negligible. A radiogenic background model is built upon the extensive radiopurity screening campaign conducted by the NEXT collaboration. A spectral fit to this model yields the specific contributions of
60
Co,
40
K,
214
Bi and
208
Tl to the total background rate, as well as their location in the detector volumes. The results are used to evaluate the impact of the radiogenic backgrounds in the double beta decay analyses, after the application of topological cuts that reduce the total rate to (0.25
±
0.01) mHz. Based on the best-fit background model, the NEXT-White median sensitivity to the two-neutrino double beta decay is found to be 3.5
σ
after 1 year of data taking. The background measurement in a Q
ββ
±
100 keV energy window validates the best-fit background model also for the neutrinoless double beta decay search with NEXT-100. Only one event is found, while the model expectation is (0.75
±
0.12) events.
Minimally invasive non-surgical techniques have been widely used worldwide to treat musculoskeletal injuries. Of these techniques, injectable pharmaceutical agents are the most commonly employed ...treatments, with corticosteroids being the most widely used drugs. The aim of this article is to review current scientific evidence as well as the effectiveness of minimally invasive non-surgical techniques, either alone or combined, for the treatment of plantar fasciitis.
This systematic review was conducted from April 2016 until March 2017, in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement and was registered with PROSPERO. Randomized controlled trials (RCTs) of adult patients diagnosed with plantar fasciitis were included as well as intervention studies, with a minimal sample size of 20 subjects per study (10 per group). Assessment of study eligibility was developed by three reviewers independently in an unblinded standardized manner. The physiotherapy evidence database (PEDro) scale was used to analyse the methodological quality of studies.
Twenty-nine full-text articles on minimally invasive techniques were reviewed. These articles focused on corticosteroid injections, platelet-rich plasma, Botox, dextrose injections, as well as comparative studies with dry needling vs sham needling.
The treatment of plantar fasciitis has dramatically improved in the past decade with minimally invasive techniques becoming increasingly available. Research findings have shown that the long term effects of minimally invasive (non-surgical) treatments such as shock wave therapy, botulinum toxin type-A injections, platelet-rich plasma injections and intratissue percutaneous electrolysis dry needling show similar and sometimes better results when compared to only corticosteroid injections. The latter have been the mainstay of treatment for many years despite their associated side effects both locally and systemically. To date, there is no definitive treatment guideline for plantar fasciitis, however the findings of this literature review may help inform practitioners and clinicians who use invasive methods for the treatment of plantar fasciitis regarding the levels of evidence for the different treatment modalities available.
A
bstract
In experiments searching for neutrinoless double-beta decay, the possibility of identifying the two emitted electrons is a powerful tool in rejecting background events and therefore ...improving the overall sensitivity of the experiment. In this paper we present the first measurement of the efficiency of a cut based on the different event signatures of double and single electron tracks, using the data of the NEXT-White detector, the first detector of the NEXT experiment operating underground. Using a
228
Th calibration source to produce signal-like and background-like events with energies near 1.6 MeV, a signal efficiency of 71
.
6
±
1
.
5
stat
±
0
.
3
sys
% for a background acceptance of 20
.
6
±
0
.
4
stat
±
0
.
3
sys
% is found, in good agreement with Monte Carlo simulations. An extrapolation to the energy region of the neutrinoless double beta decay by means of Monte Carlo simulations is also carried out, and the results obtained show an improvement in background rejection over those obtained at lower energies.
A
bstract
Excellent energy resolution is one of the primary advantages of electroluminescent high-pressure xenon TPCs. These detectors are promising tools in searching for rare physics events, such ...as neutrinoless double-beta decay (
ββ
0
ν
), which require precise energy measurements. Using the NEXT-White detector, developed by the NEXT (Neutrino Experiment with a Xenon TPC) collaboration, we show for the first time that an energy resolution of 1% FWHM can be achieved at 2.6 MeV, establishing the present technology as the one with the best energy resolution of all xenon detectors for
ββ
0
ν
searches.
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